Render: admit 16K spp with paged GPU storage and RAM budgets

Expose 16,384 spp in the native controls and raise the finite Workstation
memory and work envelopes for combined 8K, X2, adaptive sampling, photons,
denoising, diagnostics, raw output and photographic effects.

Page GPU film storage and use bounded denoise windows with complete halos,
while preserving global sample identity, adaptive previews, photon epochs
and categorical diagnostics. Keep actual device limits enforced.

Share a native available-RAM ledger across CPU and registered GPU hosts,
freeze Auto worker counts at admission, and retain exact custom counts.

Address review compatibility findings for OBJ smoothing and flat import,
firefly-off filtering, optical endpoint diagnostics, CPU finite path depth,
headless size echoes and legacy saved CPU dimensions. Restore canonical
quality presets and keep the adaptive pilot editor on its separate bound.

.gitattributes

@@ -1,6 +1,9 @@
 # Preserve canonical source receipts and the runtime icon-discovery snapshot.
 .gitattributes text eol=lf
 /assets/icons/ui/design/requested_icons.txt text eol=lf
+# Shaders reach the code through include_str!, and tests match multi-line WGSL excerpts
+# written as Rust strings (always LF), so a CRLF checkout must not change them (#13138).
+*.wgsl text eol=lf
 # SolidCraft designs (.sc): a JSON document or a ZIP container, never Scala source, so they
 # stay out of GitHub's language statistics. Git's own text/binary detection handles both kinds.
 *.sc -linguist-detectable

.github/workflows/release.yml

@@ -725,10 +725,16 @@ jobs:
         run: |
           tag="v$VERSION"
           sha256sum --check SHA256SUMS.txt
+          # Generated notes start at the newest published release, pre-releases included. Left
+          # to GitHub they start at the Latest stable one, and the list outgrows the 125,000
+          # characters a release body may have.
+          start=()
+          prev="$(gh release list --exclude-drafts --limit 30 --json tagName,publishedAt --jq 'sort_by(.publishedAt) | last | .tagName // empty')"
+          if [ -n "$prev" ]; then start=(--notes-start-tag "$prev"); fi
           # Stage all packages before publishing. Published tags are never replaced.
           gh release create "$tag" --draft --prerelease --latest=false \
             --title "SolidCraft v$VERSION (nightly)" --target "$GITHUB_SHA" \
-            --notes-file ../notes.md --generate-notes -- *
+            --notes-file ../notes.md --generate-notes "${start[@]}" -- *
           gh release edit "$tag" --draft=false --prerelease --latest=false
           echo "### Published nightly: $tag (\`${GITHUB_SHA::9}\`)" >>"$GITHUB_STEP_SUMMARY"
       - name: Create or update the draft release
@@ -760,8 +766,13 @@ jobs:
               --target "$GITHUB_SHA" --prerelease="$PRERELEASE"
             gh release upload "$tag" --clobber -- *
           else
+            # As for nightlies: start the generated notes at the newest published release.
+            start=()
+            prev="$(gh release list --exclude-drafts --limit 30 --json tagName,publishedAt --jq 'sort_by(.publishedAt) | last | .tagName // empty')"
+            if [ -n "$prev" ]; then start=(--notes-start-tag "$prev"); fi
             gh release create "$tag" --draft --title "SolidCraft v$VERSION" \
-              --target "$GITHUB_SHA" --notes-file ../notes.md --generate-notes "${pre[@]}" -- *
+              --target "$GITHUB_SHA" --notes-file ../notes.md --generate-notes "${start[@]}" \
+              "${pre[@]}" -- *
           fi
           {
             echo "Draft **SolidCraft v$VERSION** at \`${GITHUB_SHA::9}\`:"

ATTRIBUTION.md

@@ -842,6 +842,8 @@ Original SolidCraft drawings, Open for owner review; no runtime assignments.
 | crates/sketch/assets/fonts/liberation-sans/LiberationSans-Regular.ttf | Red Hat, Inc. (Liberation Fonts 2.x; digitized data Google) | https://github.com/liberationfonts (Debian fonts-liberation), unmodified; licence text in crates/sketch/assets/fonts/liberation-sans/OFL.txt; used for sketch Text outlines | SIL OFL 1.1 |
 | crates/sketch/assets/fonts/liberation-sans/OFL.txt | Red Hat, Inc.; Liberation Fonts contributors | Unmodified accompanying font licence | SIL OFL 1.1 |
 | assets/locales/pending/drag-to-zoom.json | SolidCraft contributors | Original drag-to-zoom labels and translations | MIT OR Apache-2.0 |
+| `assets/locales/pending/hole-group-folder.json` | SolidCraft contributors | Original Hole grouping preference labels and translations | MIT OR Apache-2.0 |
+| assets/locales/pending/press-pull-dialog-title.json | SolidCraft contributors | Original Press Pull dialog title translations for SolidCraft's English catalog; no external text used | MIT OR Apache-2.0 |
 
 ## Code adapted from sibling projects
 

Cargo.lock

@@ -2508,6 +2508,15 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "ntapi"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3b335231dfd352ffb0f8017f3b6027a4917f7df785ea2143d8af2adc66980ae"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "num"
 version = "0.4.3"
@@ -2773,6 +2782,16 @@ dependencies = [
  "objc2-core-foundation",
 ]
 
+[[package]]
+name = "objc2-io-kit"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "33fafba39597d6dc1fb709123dfa8289d39406734be322956a69f0931c73bb15"
+dependencies = [
+ "libc",
+ "objc2-core-foundation",
+]
+
 [[package]]
 name = "objc2-io-surface"
 version = "0.3.2"
@@ -4051,15 +4070,16 @@ dependencies = [
 [[package]]
 name = "solidcore"
 version = "1.0.1"
-source = "git+https://github.com/tangency-labs/solidcore?rev=8ddce901671f1cebd9214a31d21895d725e886c8#8ddce901671f1cebd9214a31d21895d725e886c8"
+source = "git+https://github.com/tangency-labs/solidcore?rev=a445bdaac60a980b0e9d1dba3ee28eb7ada44f50#a445bdaac60a980b0e9d1dba3ee28eb7ada44f50"
 dependencies = [
+ "serde",
  "thiserror 2.0.21",
 ]
 
 [[package]]
 name = "solidcore-record"
 version = "0.1.0"
-source = "git+https://github.com/tangency-labs/solidcore?rev=f5e8e9a29e0c9b7cf6c4040a5bc8878382b3c62f#f5e8e9a29e0c9b7cf6c4040a5bc8878382b3c62f"
+source = "git+https://github.com/tangency-labs/solidcore?rev=a445bdaac60a980b0e9d1dba3ee28eb7ada44f50#a445bdaac60a980b0e9d1dba3ee28eb7ada44f50"
 dependencies = [
  "serde",
  "serde_json",
@@ -4068,7 +4088,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "block2 0.6.2",
  "eframe",
@@ -4106,11 +4126,11 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-3dx-client"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 
 [[package]]
 name = "solidcraft-cli"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "image",
  "log",
@@ -4124,7 +4144,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-derive"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4133,7 +4153,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-doc"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "log",
  "serde",
@@ -4152,7 +4172,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-dynamics"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "serde",
  "serde_json",
@@ -4163,7 +4183,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-engine"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "image",
  "log",
@@ -4186,7 +4206,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-geom"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "serde",
  "serde_json",
@@ -4196,7 +4216,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-gpu"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "image",
  "log",
@@ -4217,7 +4237,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-io"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "cadmpeg-core",
  "cadmpeg-ir",
@@ -4244,7 +4264,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-kernel"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "log",
  "proptest",
@@ -4263,7 +4283,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-mcp"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "image",
  "serde_json",
@@ -4273,7 +4293,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-profile"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "serde_json",
  "web-time",
@@ -4281,25 +4301,27 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-render"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "flate2",
  "image",
  "moxcms",
  "png",
+ "rayon",
  "robust",
  "serde",
  "serde_json",
  "sha2 0.10.9",
  "solidcore-record",
  "solidcraft-geom",
+ "sysinfo",
  "web-time",
  "weezl",
 ]
 
 [[package]]
 name = "solidcraft-sketch"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "harfrust",
  "serde",
@@ -4313,7 +4335,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-smlib"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "flate2",
  "log",
@@ -4326,14 +4348,14 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-space-mouse"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "serde",
 ]
 
 [[package]]
 name = "solidcraft-step"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "solidcore-record",
  "solidcraft-geom",
@@ -4342,11 +4364,11 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-testkit"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 
 [[package]]
 name = "solidcraft-ui-egui"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "arboard",
  "egui",
@@ -4378,7 +4400,7 @@ dependencies = [
 
 [[package]]
 name = "solidcraft-web"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "eframe",
  "egui",
@@ -4484,6 +4506,20 @@ dependencies = [
  "web-sys",
 ]
 
+[[package]]
+name = "sysinfo"
+version = "0.40.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e8a3edbe0394ce115f3917a00349dd242be09eb5a091ed509eaf67b55cfb8a8"
+dependencies = [
+ "libc",
+ "memchr",
+ "ntapi",
+ "objc2-core-foundation",
+ "objc2-io-kit",
+ "windows",
+]
+
 [[package]]
 name = "tempfile"
 version = "3.27.0"
@@ -5336,6 +5372,22 @@ dependencies = [
  "web-sys",
 ]
 
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
 [[package]]
 name = "winapi-util"
 version = "0.1.11"
@@ -5345,6 +5397,12 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
 [[package]]
 name = "windows"
 version = "0.62.2"
@@ -5793,7 +5851,7 @@ checksum = "e450f9b2ed1dff33c94c12589a87338689467b9c4f5d8a5710bd09a847d2c8a7"
 
 [[package]]
 name = "xtask"
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 dependencies = [
  "flate2",
  "proc-macro2",

Cargo.toml

@@ -5,7 +5,7 @@ members = ["crates/*", "apps/*", "xtask"]
 exclude = ["vendor"]
 
 [workspace.package]
-version = "0.40.0-rc.2"
+version = "0.40.0-rc.3"
 edition = "2024"
 license = "MIT OR Apache-2.0"
 rust-version = "1.95"
@@ -36,10 +36,10 @@ solidcraft-3dx-client = { path = "crates/threedx-client" }
 # move the rev on its own commit. For a
 # local checkout, add `[patch."https://github.com/tangency-labs/solidcore"] solidcore = { path =
 # "../solidcore/crates/solidcore" }` to a `.cargo/config.toml` outside the repository.
-solidcore = { git = "https://github.com/tangency-labs/solidcore", rev = "8ddce901671f1cebd9214a31d21895d725e886c8" }
+solidcore = { git = "https://github.com/tangency-labs/solidcore", rev = "a445bdaac60a980b0e9d1dba3ee28eb7ada44f50" }
 # Geometry as data (solidcore's layers §1, "Record"): the B-rep record, its structural validation
 # and the native body file. Pinned like solidcore; for a local checkout, patch it as above.
-solidcore-record = { git = "https://github.com/tangency-labs/solidcore", rev = "f5e8e9a29e0c9b7cf6c4040a5bc8878382b3c62f" }
+solidcore-record = { git = "https://github.com/tangency-labs/solidcore", rev = "a445bdaac60a980b0e9d1dba3ee28eb7ada44f50" }
 # test tooling: a dev-dependency only (xtask/src/layers.rs)
 solidcraft-testkit = { path = "crates/testkit" }
 
@@ -62,6 +62,8 @@ semver = "1"
 # constrained Delaunay + Ruppert refinement for trimmed faces (MIT OR Apache-2.0).
 spade = { version = "2.15", default-features = false, features = ["std"] }
 rayon = "1.12"
+# Native render-memory admission; RAM-only queries through a safe MIT-licensed API.
+sysinfo = { version = "0.40.1", default-features = false, features = ["system"] }
 
 # packages (3MF)
 zip = { version = "9", default-features = false, features = ["deflate"] }

apps/solidcraft-cli/tests/action_matrix.rs

@@ -1308,7 +1308,7 @@ fn edge_round_actions_keep_the_picked_body() {
             let mut unscoped = p.clone();
             unscoped.as_object_mut().unwrap().remove("body");
             let err = s.scratch().execute(id, &unscoped).unwrap_err().to_string();
-            assert!(err.contains("edges meet"), "{err}");
+            assert!(err.contains("[10, 0, 20] lies on edges of 2 bodies, Plate and Block"), "{err}");
             perform(&mut s.scratch(), &a.act, &errors(&s)).unwrap();
             tried += 1;
         }

apps/solidcraft-cli/tests/model_cache.rs

@@ -318,7 +318,7 @@ fn a_model_saved_under_another_check_mode_is_evaluated_again() {
 /// opened from its model or evaluated anew. Two edges of a 20 mm box rounded r2 (a mitre at the
 /// corner (20, 0, 20)), saved; opened, the upright edge there rounded r3: the corner all three
 /// rounded at once make (SMLib's setback corner, kernel `three_rounds_at_a_corner`), 15 faces and
-/// 7928.142563938 mm³, the same body as the design evaluated anew.
+/// 7927.72428251348 mm³, the same body as the design evaluated anew.
 #[test]
 fn a_later_round_after_opening_blends_the_saved_rounds_again() {
     let mut built = Session::default();
@@ -336,7 +336,7 @@ fn a_later_round_after_opening_blends_the_saved_rounds_again() {
         let b = &st.body("Box").unwrap().body;
         let v = solidcraft_engine::kernel::measure(b).unwrap().volume;
         assert_eq!(b.face_count(), 15);
-        assert!((v - 7928.142563938).abs() < 1e-6, "{v}");
+        assert!((v - 7927.72428251348).abs() < 1e-6, "{v}"); // solidcore#2382's setback corner
     }
     assert_eq!(model("later round", &cached), model("later round", &rebuilt));
     let _ = std::fs::remove_file(&path);

apps/solidcraft-web/src/keep.rs

@@ -173,6 +173,35 @@ pub fn is_open(open: Option<&str>, wanted: &str) -> bool {
     open == Some(wanted)
 }
 
+/// What follows once a design restored from a kept copy, or recovered, is open: it opens in
+/// stages, a few features a frame with progress and Cancel (#10198), so this waits for the answer.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum AfterOpen {
+    /// A kept copy (#10220): it is its own design again (saving goes to `path`, it is named
+    /// `name`), with its changes unsaved; then the copy `id` goes when `drop` says so.
+    KeptCopy { opened: String, id: String, path: Option<String>, name: String, drop: bool },
+    /// The saved design offered beside a kept copy: the copy `id` goes when `drop` says so.
+    KeptSaved { opened: String, id: String, drop: bool },
+    /// Unsaved work from the page's last visit: it belongs to `path` again, named `name`, unsaved.
+    Recovery { opened: String, path: Option<String>, name: String },
+}
+
+impl AfterOpen {
+    /// The file the open reads.
+    pub fn opened(&self) -> &str {
+        match self {
+            AfterOpen::KeptCopy { opened, .. } | AfterOpen::KeptSaved { opened, .. } | AfterOpen::Recovery { opened, .. } => opened,
+        }
+    }
+}
+
+/// Whether the open of `wanted` answered with `reply` put it in: the answer says so, and it is
+/// the design now open (`open`: the open design's path). A refusal, a Cancel or another file
+/// leaves the copy or the recovered work offered.
+pub fn opened(reply: &Value, open: Option<&str>, wanted: &str) -> bool {
+    reply["ok"].as_bool() == Some(true) && is_open(open, wanted)
+}
+
 /// Whether leaving the page asks through the browser's "leave site?" box: there is unsaved work,
 /// and either the user still wants to be asked or it isn't all kept in the browser yet (with the
 /// keep preference off it never is, so there the box always stays).
@@ -224,6 +253,20 @@ pub fn answers(entry: &Entry, saved_exists: bool) -> Vec<Answer> {
 mod tests {
     use super::*;
 
+    /// A restored or recovered design opens in stages (#10198): only an answer that it is in, for
+    /// the file asked for, counts; a refusal, a Cancel or another design open leaves it offered.
+    #[test]
+    fn a_staged_restore_counts_only_when_its_file_is_in() {
+        let copy = "/opfs/.kept/a.sc";
+        assert!(opened(&json!({"ok": true}), Some(copy), copy));
+        assert!(!opened(&json!({"ok": false, "error": "cancelled"}), Some(copy), copy));
+        assert!(!opened(&json!({"ok": false, "error": "not a design"}), None, copy));
+        assert!(!opened(&json!({"ok": true}), Some("/opfs/other.sc"), copy));
+        assert!(!opened(&json!({}), Some(copy), copy));
+        let after = AfterOpen::KeptCopy { opened: copy.into(), id: "a".into(), path: None, name: "Bracket".into(), drop: true };
+        assert_eq!(after.opened(), copy);
+    }
+
     fn entry(id: &str, changed_at: f64, path: Option<&str>) -> Entry {
         Entry { id: id.into(), name: "Bracket".into(), path: path.map(str::to_string), changed_at }
     }

apps/solidcraft-web/src/main.rs

@@ -382,6 +382,9 @@ mod web {
         keep_track: std::collections::HashMap<u64, Track>,
         /// Every unsaved design's kept copy is current (and the preference is on).
         all_kept: bool,
+        /// A kept copy or recovered work being opened, in stages with progress and Cancel
+        /// (#10198): the answer to come and what follows it ([`Shell::restored`]).
+        restoring: Option<(std::sync::mpsc::Receiver<serde_json::Value>, keep::AfterOpen)>,
     }
 
     impl Shell {
@@ -633,7 +636,7 @@ mod web {
         /// (when it has a file) and Discard.
         fn keep_prompt(&mut self, ctx: &egui::Context) {
             let offered = self.files.keep_offered.borrow().clone();
-            if offered.is_empty() || !self.files.ready.get() {
+            if offered.is_empty() || !self.files.ready.get() || self.restoring.is_some() {
                 return;
             }
             let now = (js_sys::Date::now() / 1000.0) as u64;
@@ -673,24 +676,21 @@ mod web {
                         return;
                     }
                 };
-                self.app.open_path(&copy);
-                if self.app.session.path.as_deref() != Some(copy.as_str()) {
-                    // Not opened (the status says why): it stays offered.
-                    return;
-                }
-                // It is its own design again (saving goes to its file), with its changes unsaved.
-                self.app.session.path = entry.path.clone();
-                self.app.session.doc_mut().name = entry.name.clone();
-                self.app.session.mark_unsaved();
-                self.app.home.open = false;
+                // Finished in `restored` once it is in.
+                let after = keep::AfterOpen::KeptCopy {
+                    opened: copy.clone(),
+                    id: entry.id.clone(),
+                    path: entry.path.clone(),
+                    name: entry.name.clone(),
+                    drop: plan.drop_copy,
+                };
+                self.restore(&copy, after);
+                return;
             }
             if let Some(path) = &plan.open_saved {
                 if vfs::exists(path) {
-                    self.app.open_path(path);
-                    if !keep::is_open(self.app.session.path.as_deref(), path) {
-                        // Not opened (the status says why): the copy stays offered.
-                        return;
-                    }
+                    self.restore(path, keep::AfterOpen::KeptSaved { opened: path.clone(), id: entry.id.clone(), drop: plan.drop_copy });
+                    return;
                 } else {
                     // A file on the computer: the browser asks for access again, in this click.
                     // The copy goes once the file has opened, not before: if access is refused,
@@ -708,8 +708,62 @@ mod web {
                 }
             }
             if plan.drop_copy {
-                self.files.keep_offered.borrow_mut().retain(|e| e.id != entry.id);
-                files::remove_kept(&self.files, &entry.id);
+                self.drop_kept(&entry.id);
+            }
+        }
+
+        fn drop_kept(&self, id: &str) {
+            self.files.keep_offered.borrow_mut().retain(|e| e.id != id);
+            files::remove_kept(&self.files, id);
+        }
+
+        /// Open a kept copy, its saved design or recovered work as any design opens, a few
+        /// features a frame with progress and Cancel (#10198), so a large design doesn't freeze the
+        /// page; `after` follows once it is in ([`Self::restored`]).
+        fn restore(&mut self, path: &str, after: keep::AfterOpen) {
+            self.restoring = Some((self.app.open_path_answered(path), after));
+            self.restored();
+        }
+
+        /// What follows a restore that is in: the design gets back its file and name, and the
+        /// copy or the recovered work it came from goes. One that didn't open (refused or
+        /// cancelled; the status says why) stays offered.
+        fn restored(&mut self) {
+            let Some((rx, _)) = &self.restoring else { return };
+            let reply = match rx.try_recv() {
+                Ok(reply) => reply,
+                Err(std::sync::mpsc::TryRecvError::Empty) => return,
+                Err(std::sync::mpsc::TryRecvError::Disconnected) => serde_json::json!({"ok": false}),
+            };
+            let Some((_, after)) = self.restoring.take() else { return };
+            if !keep::opened(&reply, self.app.session.path.as_deref(), after.opened()) {
+                return;
+            }
+            match after {
+                keep::AfterOpen::KeptCopy { id, path, name, drop, .. } => {
+                    // It is its own design again (saving goes to its file), with its changes unsaved.
+                    self.app.session.path = path;
+                    self.app.session.doc_mut().name = name;
+                    self.app.session.mark_unsaved();
+                    self.app.home.open = false;
+                    if drop {
+                        self.drop_kept(&id);
+                    }
+                }
+                keep::AfterOpen::KeptSaved { id, drop, .. } => {
+                    if drop {
+                        self.drop_kept(&id);
+                    }
+                }
+                keep::AfterOpen::Recovery { path, name, .. } => {
+                    // It belongs to its own file again (saving goes there); it is unsaved.
+                    self.app.session.path = path;
+                    self.app.session.doc_mut().name = name;
+                    self.app.session.mark_unsaved();
+                    self.app.home.open = false;
+                    *self.files.recovery.borrow_mut() = None;
+                    files::autosave(&self.files, None);
+                }
             }
         }
 
@@ -917,6 +971,9 @@ mod web {
 
         /// Offer the autosave an earlier session left.
         fn recovery_prompt(&mut self, ctx: &egui::Context) {
+            if self.restoring.is_some() {
+                return;
+            }
             let Some((name, path)) = self.files.recovery.borrow().clone() else { return };
             let mut answer = None;
             let _ = solidcraft_ui_egui::ui_kit::Window::new(egui::Id::unique("sc_browser_recovery"), "restore", "Recover unsaved work?")
@@ -941,15 +998,10 @@ mod web {
                         return;
                     }
                 };
-                self.app.open_path(&recovery);
-                if self.app.session.path.as_deref() != Some(recovery.as_str()) {
-                    return;
-                }
-                // It belongs to its own file again (saving goes there); it is unsaved.
-                self.app.session.path = path;
-                self.app.session.doc_mut().name = name;
-                self.app.session.mark_unsaved();
-                self.app.home.open = false;
+                // Finished in `restored` once it is in; until then the prompt stays away.
+                let after = keep::AfterOpen::Recovery { opened: recovery.clone(), path, name };
+                self.restore(&recovery, after);
+                return;
             }
             *self.files.recovery.borrow_mut() = None;
             files::autosave(&self.files, None);
@@ -1093,6 +1145,7 @@ mod web {
         }
         fn ui(&mut self, ui: &mut egui::Ui, _frame: &mut eframe::Frame) {
             self.linked.tick(&mut self.app, ui.ctx());
+            self.restored();
             UNSAVED.with(|u| u.set(self.asks_before_unload()));
             if self.launch.embed {
                 ui_kit::Container::new(ui.ctx(), ui_kit::Surface::Chrome).edge("embed_header", ui_kit::Edge::Top).show(ui, |ui| {
@@ -1306,6 +1359,7 @@ mod web {
                             other_tab_prefs,
                             keep_track: Default::default(),
                             all_kept: false,
+                            restoring: None,
                         }))
                     }),
                 )

assets/locales/ar.json

@@ -265,6 +265,7 @@
   "Edge": "حافة",
   "Edges": "الحواف",
   "Edit": "تعديل",
+  "Edit Holes": "تحرير الثقوب",
   "Edit Profile Sketch": "تعديل رسم المقطع",
   "Edit shortcuts": "تعديل الاختصارات",
   "Enable rule": "تفعيل القاعدة",
@@ -976,7 +977,7 @@
   "browser.calibrate_click_a": "انقر على الصورة لتحديد النقطة A، أو اكتب إحداثياتها.",
   "browser.calibrate_click_b": "انقر على الصورة لتحديد النقطة B، أو اكتب إحداثياتها.",
   "browser.calibrate_title": "معايرة: {name}",
-  "browser.canvas_locked": "اللوحة مقفلة. ألغِ قفلها أولاً.",
+  "browser.canvas_locked": "اللوحة مقفلة. ألغِ قفلها أولًا.",
   "browser.capture_many": "تم تحريك {count} مكوّنات دون تثبيت مواضعها.",
   "browser.capture_note": "التثبيت يحتفظ بالموضع الجديد، والإرجاع يعيده كما كان.",
   "browser.capture_one": "تم تحريك مكوّن دون تثبيت موضعه.",
@@ -1206,6 +1207,7 @@
   "cmd.material_properties_directional": "معامل المرونة الاتجاهي",
   "cmd.material_properties_validate": "التحقق من بيانات المادة الفيزيائية",
   "cmd.mesh_convert": "تحويل الشبكة",
+  "cmd.model_body_features": "سرد ميزات الجسم",
   "cmd.model_edges": "قائمة الحواف",
   "cmd.model_faces": "قائمة الأوجه",
   "cmd.model_threads": "قائمة الأسنان اللولبية",
@@ -1234,8 +1236,11 @@
   "cmd.panel.dismiss": "إغلاق العرض المؤقت للوحة",
   "cmd.panel.float": "تعويم اللوحة",
   "cmd.panel.focus": "تركيز اللوحة",
+  "cmd.panel.focus.next": "التركيز على اللوحة التالية",
+  "cmd.panel.focus.previous": "التركيز على اللوحة السابقة",
   "cmd.panel.list": "سرد اللوحات",
   "cmd.panel.move": "نقل اللوحة",
+  "cmd.panel.move.next_zone": "نقل اللوحة إلى المنطقة التالية",
   "cmd.panel.native_close": "إعادة إرساء قسم اللوحة من نافذته المستقلة",
   "cmd.panel.open": "فتح اللوحة",
   "cmd.panel.peek": "عرض اللوحة المطوية مؤقتًا",
@@ -1243,6 +1248,12 @@
   "cmd.panel.reset_pair": "إعادة ضبط فاصل اللوحة",
   "cmd.panel.resize": "تغيير حجم قسم اللوحة",
   "cmd.panel.resize_pair": "تحريك فاصل اللوحة",
+  "cmd.panel.sash.down": "تحريك فاصل اللوحة لأسفل",
+  "cmd.panel.sash.left": "تحريك فاصل اللوحة لليسار",
+  "cmd.panel.sash.reset": "إعادة تعيين فاصل اللوحة المحدد",
+  "cmd.panel.sash.right": "تحريك فاصل اللوحة لليمين",
+  "cmd.panel.sash.up": "تحريك فاصل اللوحة لأعلى",
+  "cmd.panel.toggle": "تبديل طي اللوحة المحددة",
   "cmd.parameters_add": "إضافة معامل مستخدم",
   "cmd.parameters_change": "تغيير المعاملات",
   "cmd.parameters_comment": "التعليق على المعامل",
@@ -1366,6 +1377,7 @@
   "cmd.sketch.construction_line.tangent_external": "مماس يمر بنقطة خارجية",
   "cmd.sketch.construction_line.tangent_two": "مماس مشترك",
   "cmd.sketch.construction_line.vertical": "خط إنشائي رأسي",
+  "cmd.sketch.replace": "استبدال الرسم",
   "cmd.sketch_arc3d": "قوس ثلاثي الأبعاد",
   "cmd.sketch_arc_center_point": "قوس بنقطة مركز",
   "cmd.sketch_arc_tangent": "قوس مماسي",
@@ -1862,7 +1874,7 @@
   "help.sketch.constrainer": "يطبق القيد الذي يكاد منحنى أو منحنيان محددان يحققانه، مثل الأفقي أو التوازي أو التماس أو التساوي. استخدمه لتهذيب رسم يدوي علاقة بعد أخرى.",
   "help.sketch.constraint.coincident": "يجعل نقطة تقع على نقطة أخرى أو على منحنى أو على محور الرسم. استخدمه لسد الفجوات في المقطع أو لوضع نقطة على خط.",
   "help.sketch.constraint.collinear": "يجعل خطين يقعان على خط مستقيم واحد. استخدمه لمحاذاة الحواف المتقطعة، مثل جانبي حز.",
-  "help.sketch.constraint.concentric": "يجعل دائرتين أو قوسين يشتركان في المركز نفسه، أو يضع مركز دائرة أو قوس على نقطة في الرسم التخطيطي، بما في ذلك نقطة الأصل. اختر العنصرين بأي ترتيب.",
+  "help.sketch.constraint.concentric": "يجعل دائرتين أو قوسين يشتركان في المركز نفسه، أو يضع مركز دائرة أو قوس على نقطة في الرسم، بما في ذلك نقطة الأصل. اختر العنصرين بأي ترتيب.",
   "help.sketch.constraint.curvature": "يجعل منحنيين يلتقيان عند نقطة نهاية يتابعان بالانحناء نفسه (G2). استخدمه حيث لا يكفي الوصل المماسي نعومة، مثلًا على الأسطح الظاهرة.",
   "help.sketch.constraint.equal": "يجعل الخطوط بالطول نفسه، أو الدوائر والأقواس بنصف القطر نفسه. استخدمه ليتحكم بُعد واحد في عدة ميزات متماثلة.",
   "help.sketch.constraint.fix": "يثبّت النقاط أو المنحنيات في مكانها، أو يفك تثبيتها. استخدمه للهندسة التي يجب ألا تتحرك عند سحب الرسم أو حله.",
@@ -2016,6 +2028,7 @@
   "help.view.visual_style": "يبدّل طريقة رسم النموذج: مظلَّل مع الحواف أو بدونها، أو إطار سلكي، أو مع الحواف المخفية. استخدم الإطار السلكي لرؤية الداخل، والمظلَّل لمظهر نظيف.",
   "history.sketch_under_constrained": "قيود ناقصة ({count} درجات حرية)",
   "history.sketch_under_constrained_one": "قيود ناقصة ({count} درجة حرية)",
+  "hole_folder.applies_to": "تنطبق التغييرات على الثقوب الـ {count} في {folder}؛ ويحتفظ كل ثقب بموضعه.",
   "hole_presets.confirm_delete": "تأكيد الحذف",
   "hole_presets.delete": "حذف",
   "hole_presets.delete_prompt": "هل تحذف هذا الإعداد المسبق الشخصي؟ الثقوب الموجودة لا تتغير.",
@@ -2515,6 +2528,8 @@
   "prefs.bottom_centre": "أسفل الوسط",
   "prefs.bottom_right": "أسفل اليمين",
   "prefs.browser": "المستعرض",
+  "prefs.browser_body_features": "الميزات تحت الأجسام",
+  "prefs.browser_body_features_note": "يمكن فتح كل جسم في المستعرض لعرض ميزات الخط الزمني التي بنته، بترتيب الخط الزمني.",
   "prefs.browser_components_open": "المكوّنات مفتوحة من البداية",
   "prefs.browser_components_open_note": "يبدأ كل مكوّن في المستعرض مفتوحًا كما كان من قبل، بدلًا من أن يبقى مغلقًا حتى تفتحه.",
   "prefs.browser_eye_left": "أيقونة الإظهار بجانب سهم الطي",
@@ -2555,7 +2570,11 @@
   "prefs.design_tools.degrees": "درجات",
   "prefs.design_tools.double_click_help": "أو لتحرير مكوّن مرتبط في موضعه.",
   "prefs.design_tools.ghost": "إظهار الموضع القديم للأجزاء المنقولة كشبح",
+  "prefs.design_tools.hole_group": "تجميع الثقوب المُنشأة معًا",
+  "prefs.design_tools.hole_group_help": "الثقوب المُنشأة دفعة واحدة تشترك في مجلد واحد في السجل يبدأ مطويًا؛ افتحه لتحرير كل ثقب على حدة.",
   "prefs.design_tools.hole_moves_help": "اختيار الوجه مجددًا ينقل الثقب بدلًا من إزالته.",
+  "prefs.design_tools.hole_several": "عدة ثقوب على وجه واحد",
+  "prefs.design_tools.hole_several_help": "الاختيار في موضع آخر من الوجه يضيف ثقبًا آخر، واختيار ثقب يزيله.",
   "prefs.design_tools.hole_snaps_help": "منتصف الوجه ومراكز حوافه الدائرية.",
   "prefs.design_tools.imported_files": "الملفات المستوردة",
   "prefs.design_tools.note": "ملاحظة",
@@ -2637,6 +2656,8 @@
   "prefs.history": "السجل",
   "prefs.history_bar_groups": "طي شريط السجل في مجموعات",
   "prefs.history_bar_groups_note": "في سجل طويل، تُطوى سلسلة ميزات المكوّن الواحد في شريحة واحدة، وتبدأ مجلدات الميزات مطوية. تدخل مجموعة STEP المُدرجة في مجلد Group. عند الإيقاف تظهر كل ميزة، وتبدأ المجلدات مفتوحة، ولا يُنشأ أي مجلد.",
+  "prefs.history_folder_kind_icon": "أيقونة المجلد من ميزاته",
+  "prefs.history_folder_kind_icon_note": "مجلد السجل الذي تكون ميزاته كلها من نوع واحد يعرض أيقونتها.",
   "prefs.history_group_joints": "تجميع المفاصل في السجل",
   "prefs.history_group_joints_note": "يظهر مفصلان أو أكثر كزر واحد مع عددها، والنقر عليه يُظهر كل مفصل. عند الإيقاف يظهر كل مفصل على حدة.",
   "prefs.history_origin_bodies": "إظهار الأصل والأجسام في الأعلى",
@@ -2828,8 +2849,10 @@
   "prefs.select_hidden_edges_help": "يتيح تحديد الحواف عبر الأوجه عند تفعيل نمط «مظلل مع الحواف المخفية»، بما في ذلك عند استخدام التقويس. عند الإيقاف يبقى سلوك التحديد كما في v0.30.1. تظل الأجسام المخفية غير قابلة للتحديد.",
   "prefs.select_one_item": "تحديد عنصر واحد",
   "prefs.select_other_hidden": "تحديد العناصر الهندسية المخفية باستخدام «تحديد عنصر آخر»",
-  "prefs.select_other_hidden_help": "عند التفعيل: تضمين الأجسام والمخططات المخفية والحواف المحجوبة قرب المؤشر. عند التعطيل: استخدام القائمة الأصلية للعناصر الهندسية المرئية أسفل المؤشر.",
+  "prefs.select_other_hidden_help": "عند التفعيل: تضمين الأجسام والرسومات المخفية والحواف المحجوبة قرب المؤشر. عند التعطيل: استخدام القائمة الأصلية للعناصر الهندسية المرئية أسفل المؤشر.",
   "prefs.selecting": "التحديد",
+  "prefs.shared_panel_layout": "استخدام تخطيط اللوحات المشترك",
+  "prefs.shared_panel_layout_help": "استخدم المتصفح والسجل والمساعد داخل لوحات قابلة للنقل. يسري التغيير بعد تطبيق التفضيلات.",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift يضيف فقط، وCtrl / Cmd يبدّل",
   "prefs.shift_add_note": "عند التشغيل: Shift يضيف، وCtrl / Cmd يبدّل. عند الإيقاف (الافتراضي): كلاهما يبدّل.",
@@ -2852,8 +2875,8 @@
   "prefs.sketch.drawing": "الرسم",
   "prefs.sketch.ellipse_axes": "رسم القطوع الناقصة مع محاورها",
   "prefs.sketch.ellipse_axes_note": "المحوران الأكبر والأصغر كخطوط مساعدة، لتحديد أبعاد أنصاف المحاور والمحاور. عند الإيقاف: القطع الناقص وحده، ويعطي D عليه نصف قطره الأصغر أينما سُحبت القيمة، مرسومًا ومُعلَّمًا بـ R كما في السابق.",
-  "prefs.sketch.escape_twice_finishes": "الضغط المزدوج على Esc ينهي الرسم التخطيطي",
-  "prefs.sketch.escape_twice_finishes_note": "ضغطتان سريعتان على Esc تنهيان الرسم التخطيطي. عند الإيقاف: يلغي Esc الأداة أو التحديد فقط، وينهي أمر «إنهاء الرسم» الرسم التخطيطي.",
+  "prefs.sketch.escape_twice_finishes": "الضغط على Esc مرتين ينهي الرسم",
+  "prefs.sketch.escape_twice_finishes_note": "ضغطتان سريعتان على Esc تنهيان الرسم. عند الإيقاف: يلغي Esc الأداة أو التحديد فقط، وينهي أمر «إنهاء الرسم» الرسم.",
   "prefs.sketch.exit_keep": "إبقاء",
   "prefs.sketch.exit_previous": "العودة إلى العرض السابق",
   "prefs.sketch.exit_unless_rotated": "إلا إذا تم التدوير",
@@ -3074,7 +3097,7 @@
   "render.aging_metallic": "النسبة المعدنية للطبقة",
   "render.aging_origin": "أصل الحقل · mm العالم",
   "render.aging_patina": "زنجار نحاسي أخضر",
-  "render.aging_raytrace_help": "يُطبّق التعتيق في تتبع الأشعة على المعالج وتتبع المسارات على المعالج الرسومي. يبقى التصيير النقطي تخطيطياً.",
+  "render.aging_raytrace_help": "يُطبّق التعتيق في تتبع الأشعة على المعالج وتتبع المسارات على المعالج الرسومي. يبقى التصيير النقطي تخطيطيًا.",
   "render.aging_refresh_targets": "فحص الأجسام الحالية",
   "render.aging_roughness": "خشونة الطبقة",
   "render.aging_rust": "حديد مؤكسد / صدأ",
@@ -3374,7 +3397,7 @@
   "render.cpu_opaque_required": "يتطلب تتبع الأشعة على CPU خلفية معتمة. ألغِ تحديد «خلفية شفافة» للمتابعة.",
   "render.cpu_options_pending": "لا تستطيع لوحة CPU هذه تحرير الانبعاث ولا تأثيرات السطح ولا الزجاج ولا تباين الخواص بعد. امسح خيارات API هذه قبل استخدامها.",
   "render.cpu_path_depth": "عمق المسار",
-  "render.cpu_path_help": "تحسب الضوء المرتد بين الأسطح المعتمة والمار عبر أشكال الزجاج المدعومة. تتطلب التصيير التدريجي وظلال تتبع الأشعة. يحسب عمق المسار الأسطح المضاءة وحدود الزجاج وأحداث التشتت بدءاً من أول تقاطع (1–16). يقتصر العمق 1 على الإضاءة المباشرة للأسطح المعتمة؛ وتسمح القيم الأعلى بمزيد من الارتدادات أو عبور الزجاج وقد تستغرق وقتاً أطول. أوقف الإضاءة غير المباشرة لاستخدام الانعكاسات المخصصة أو التباين الاتجاهي.",
+  "render.cpu_path_help": "تضيف الضوء المرتد بين الأسطح المعتمة والمار عبر أشكال الزجاج المدعومة. تتطلب التصيير التدريجي وظلال تتبع الأشعة. يحسب عمق المسار الأسطح المضاءة وحدود الزجاج وأحداث التشتت بدءًا من أول تقاطع (1–64). يقتصر العمق 1 على الإضاءة المباشرة للأسطح المعتمة؛ وتسمح القيم الأعلى بمزيد من الارتدادات أو عبور الزجاج وقد تستغرق وقتًا أطول. أوقف الإضاءة غير المباشرة لاستخدام الانعكاسات المخصصة أو التباين الاتجاهي.",
   "render.cpu_path_lighting": "إضاءة غير مباشرة",
   "render.cpu_path_optics_reason": "تبقى إعداداتك كما هي. أوقف الإضاءة غير المباشرة لاستخدام الانعكاسات المخصصة أو التباين الاتجاهي.",
   "render.cpu_point": "ضوء نقطي",
@@ -3409,8 +3432,8 @@
   "render.cpu_sky_bounds": "يجب أن يكون دوران السماء محدودًا ضمن ±1,000,000 راديان، وأن تكون الشدة بين 0 و100.",
   "render.cpu_studio_enable": "تفعيل الإضاءة غير المباشرة لهذا التوزيع",
   "render.cpu_studio_enable_apply": "تفعيل الإضاءة غير المباشرة وتطبيقها",
-  "render.cpu_studio_indirect_help": "يحتاج توزيع الشمس هذا إلى إضاءة غير مباشرة بعمق 8 وظلال متتبعة وعينة كاميرا واحدة لكل مرور. إذا كان التصيير التدريجي معطلاً، يبدأ بـ 16 عينة لكل بكسل وبذرة 0. تُحفظ الإعدادات التدريجية الحالية وملف الموارد. تمنع الإعدادات غير المتوافقة التطبيق دون تغييرها.",
-  "render.cpu_studio_radiance_limit": "سطوع المصدر المساحي في هذا التوزيع هو {radiance}، ويتجاوز حد CPU البالغ 64. تُحفظ الإضاءة المؤلَّفة؛ اختر توزيعاً آخر أو GPU.",
+  "render.cpu_studio_indirect_help": "يحتاج توزيع الشمس هذا إلى إضاءة غير مباشرة بعمق 8 وظلال متتبعة وعينة كاميرا واحدة لكل مرور. إذا كان التصيير التدريجي معطلًا، يبدأ بـ 16 عينة لكل بكسل وبذرة 0. تُحفظ الإعدادات التدريجية الحالية وملف الموارد. تمنع الإعدادات غير المتوافقة التطبيق دون تغييرها.",
+  "render.cpu_studio_radiance_limit": "سطوع المصدر المساحي في هذا التوزيع هو {radiance}، ويتجاوز حد CPU البالغ 64. تُحفظ الإضاءة المؤلَّفة؛ اختر توزيعًا آخر أو GPU.",
   "render.cpu_subsurface_denoise_reason": "يتطلب التشتت داخل الزجاج على CPU إيقاف إزالة الضجيج. تبقى إعداداتك محفوظة.",
   "render.cpu_subsurface_help": "يغيّر التشتت اتجاه الضوء داخل الزجاج المغلق. تتطلب المعدلات الموجبة إضاءة غير مباشرة مع إيقاف إزالة الضجيج. المعدل هو عدد التصادمات لكل مم؛ لا يضيف الصفر أي تشتت. يفضّل انحياز الاتجاه الموجب الأمام، والسالب الخلف.",
   "render.cpu_summary": "تتبع الأشعة على CPU · انعكاسات · HDR · أضواء اتجاهية ونقطية",
@@ -3430,7 +3453,7 @@
   "render.diag_preflight_details": "تفاصيل الفحص المسبق",
   "render.diag_request": "الطلب الحالي بالضبط",
   "render.diag_triangles": "المثلثات",
-  "render.directional_sun_limit": "تدعم إضاءة GPU ثمانية مصادر ضوء اتجاهية إجمالاً، من بينها شمس واحدة بظلال ناعمة كحد أقصى. انسخ ضوءاً اتجاهياً بظلال حادة لإضافة مصدر بعيد آخر.",
+  "render.directional_sun_limit": "تدعم إضاءة GPU ثمانية مصادر ضوء اتجاهية إجمالًا، من بينها شمس واحدة بظلال ناعمة كحد أقصى. انسخ ضوءًا اتجاهيًا بظلال حادة لإضافة مصدر بعيد آخر.",
   "render.discard_continue": "تجاهل المسودة والمتابعة",
   "render.draft_confirm_help": "في مسودة التصيير الحالية تعديلات غير مطبّقة. احفظها قبل التبديل، أو تجاهلها صراحةً، أو تابع التحرير.",
   "render.draft_confirm_title": "الحفاظ على إعدادات التصيير المعدّلة",
@@ -4014,7 +4037,7 @@
   "render.output_lock_ratio": "قفل نسبة الأبعاد",
   "render.output_master_unavailable": "لتصدير EXR، اختر صورة مكتملة تحتوي على بيانات EXR خام. فعّل EXR الخام قبل تصيير صور جديدة.",
   "render.output_over_budget": "الصورة المطلوبة تتجاوز نطاق الموارد المختار. اختر حجمًا أو ملفًا متوافقًا صراحةً؛ لا يحدث تخفيض تلقائي.",
-  "render.output_presentation_limits": "تدعم مؤثرات الصور على CPU وإخراج EXR صوراً بعرض وارتفاع لا يتجاوزان 8192 بكسل، وبإجمالي لا يتجاوز 16,777,216 بكسل.",
+  "render.output_presentation_limits": "تدعم مؤثرات الصور على CPU وإخراج EXR صورًا بعرض وارتفاع لا يتجاوزان 8192 بكسل، وبإجمالي لا يتجاوز 16,777,216 بكسل.",
   "render.output_presets_help": "الصيغة والجودة وقائمة الفحص في محرر المخرجات.",
   "render.output_quality": "الجودة",
   "render.output_quality_waiting": "بانتظار عقد الجودة",
@@ -4265,7 +4288,7 @@
   "render.soft_focus": "تركيز ناعم",
   "render.spot_axis": "اتجاه انبعاث الضوء",
   "render.spot_cone": "مخروط الكشّاف",
-  "render.spot_gpu_help": "تُقاس الزوايا من اتجاه انبعاث الضوء. يتلاشى الضوء بين الزاويتين الداخلية والخارجية. تتطلب نطاقات التلاشي الضيقة جداً التصيير باستخدام CPU.",
+  "render.spot_gpu_help": "تُقاس الزوايا من اتجاه انبعاث الضوء. يتلاشى الضوء بين الزاويتين الداخلية والخارجية. تتطلب نطاقات التلاشي الضيقة جدًا التصيير باستخدام CPU.",
   "render.spot_help": "تُقاس الزوايا من اتجاه انبعاث الضوء. يتلاشى الضوء بين الزاويتين الداخلية والخارجية.",
   "render.spot_inner": "نصف الزاوية الداخلية",
   "render.spot_outer": "نصف الزاوية الخارجية",
@@ -5446,7 +5469,7 @@
   "ui.finest": "الأدق",
   "ui.finish_sketch": "إنهاء الرسم",
   "ui.first_dimension_scales": "البُعد الأول يغيّر مقياس الرسم",
-  "ui.first_dimension_scales_tip": "تشغيل: أول بُعد طولي في المخطط يغيّر مقياس الرسم الذي يقيسه، فيبقى شكله كما هو. إيقاف: يغيّر البُعد حجم ما يقيسه فقط.",
+  "ui.first_dimension_scales_tip": "تشغيل: أول بُعد طولي في الرسم يغيّر مقياس الشكل الذي يقيسه، فيبقى شكله كما هو. إيقاف: يغيّر البُعد حجم ما يقيسه فقط.",
   "ui.fit": "ملاءمة",
   "ui.fix_unfix": "تثبيت/فك التثبيت",
   "ui.flat": "مسطّح",
@@ -5520,6 +5543,7 @@
   "ui.heading_plastic": "البلاستيك",
   "ui.heading_position": "الموضع",
   "ui.heading_prepare": "تحضير",
+  "ui.heading_press_pull": "ضغط وسحب",
   "ui.heading_rectangular_pattern": "نمط مستطيلي",
   "ui.heading_revolve": "دوران",
   "ui.heading_right": "يمين",
@@ -5771,7 +5795,7 @@
   "ui.panel_layout.custom_hint": "تم نقل اللوحات منذ {name}.",
   "ui.panel_layout.details": "التفاصيل",
   "ui.panel_layout.layout_workspace": "مساحة عمل التخطيط",
-  "ui.panel_layout.page_defaults_hint": "إعادة ضبط إعدادات هذه الصفحة. تُحفظ ترتيبات اللوحات والتخطيطات المحفوظة.",
+  "ui.panel_layout.page_defaults_hint": "يعيد ضبط إعدادات هذه الصفحة. تُحفظ ترتيبات اللوحات والتخطيطات المحفوظة.",
   "ui.panel_layout.panel_layout": "تخطيط اللوحات",
   "ui.panel_layout.panel_style": "نمط اللوحات",
   "ui.panel_layout.replace": "استبدال التخطيط",
@@ -5796,7 +5820,7 @@
   "ui.panel_layout.workspace.modelling": "النمذجة",
   "ui.panel_layout.workspace.render": "التصيير",
   "ui.panel_layout.workspace.review": "المراجعة",
-  "ui.panel_layout.workspace.sketch": "الرسم التخطيطي",
+  "ui.panel_layout.workspace.sketch": "الرسم",
   "ui.panel_layout.your_layout": "تخطيطك",
   "ui.parallel": "متوازي",
   "ui.parameters": "المعاملات",
@@ -5863,6 +5887,8 @@
   "ui.profiles": "المقاطع",
   "ui.project": "إسقاط",
   "ui.project_face_edges_sketch": "إسقاط حواف الوجه في رسومات جديدة",
+  "ui.project_references_construction": "إسقاط المراجع كهندسة مساعدة",
+  "ui.project_references_construction_note": "ينشئ الإسقاط والتقاطع وتضمين الهندسة ثلاثية الأبعاد وحواف الوجه لرسم جديد على وجه هندسةً مساعدة: مراجع للرسم عليها لا تدخل في المقاطع. وتبقى مرتبطة بالنموذج.",
   "ui.properties": "الخصائص",
   "ui.properties.copy_matrix": "نسخ المصفوفة",
   "ui.properties.first_moments": "العزوم الأولى",
@@ -5906,6 +5932,8 @@
   "ui.renderer": "محرك التصيير",
   "ui.repeat": "تكرار",
   "ui.repeat_nothing": "لا يوجد ما يُكرَّر بعد: ابدأ أداة أو مربع حوار أولًا.",
+  "ui.replace_sketch.from_file": "من ملف تصميم…",
+  "ui.replace_sketch.no_sketches": "لا يحتوي هذا التصميم على رسم يمكن أخذه",
   "ui.replace_with_link_done": "أصبحت النسخ الآن مواضع للتصميم المرتبط.",
   "ui.report_a_bug": "الإبلاغ عن خطأ",
   "ui.report_characters_left_one": "الأحرف المتبقية: {count}",

assets/locales/de.json

@@ -206,6 +206,7 @@
   "Edge": "Kante",
   "Edges": "Kanten",
   "Edit": "Bearbeiten",
+  "Edit Holes": "Bohrungen bearbeiten",
   "Edit Profile Sketch": "Profile-Skizze bearbeiten",
   "Edit shortcuts": "Tastenkürzel bearbeiten",
   "Enable rule": "Regel aktivieren",
@@ -1017,6 +1018,7 @@
   "cmd.material_properties_directional": "Richtungsabhängiger Elastizitätsmodul",
   "cmd.material_properties_validate": "Physikalische Materialdaten prüfen",
   "cmd.mesh_convert": "Netz konvertieren",
+  "cmd.model_body_features": "Körper-Features auflisten",
   "cmd.model_edges": "Kanten auflisten",
   "cmd.model_faces": "Flächen auflisten",
   "cmd.model_threads": "Gewinde auflisten",
@@ -1045,8 +1047,11 @@
   "cmd.panel.dismiss": "Panel-Vorschau schließen",
   "cmd.panel.float": "Panel frei platzieren",
   "cmd.panel.focus": "Panel fokussieren",
+  "cmd.panel.focus.next": "Nächstes Panel fokussieren",
+  "cmd.panel.focus.previous": "Vorheriges Panel fokussieren",
   "cmd.panel.list": "Panels auflisten",
   "cmd.panel.move": "Panel verschieben",
+  "cmd.panel.move.next_zone": "Panel in nächste Zone verschieben",
   "cmd.panel.native_close": "Nativen Panel-Bereich wieder andocken",
   "cmd.panel.open": "Panel öffnen",
   "cmd.panel.peek": "Eingeklapptes Panel anzeigen",
@@ -1054,6 +1059,12 @@
   "cmd.panel.reset_pair": "Panel-Trennlinie zurücksetzen",
   "cmd.panel.resize": "Panel-Bereich skalieren",
   "cmd.panel.resize_pair": "Panel-Trennlinie verschieben",
+  "cmd.panel.sash.down": "Panel-Trennlinie nach unten verschieben",
+  "cmd.panel.sash.left": "Panel-Trennlinie nach links verschieben",
+  "cmd.panel.sash.reset": "Trennlinie des fokussierten Panels zurücksetzen",
+  "cmd.panel.sash.right": "Panel-Trennlinie nach rechts verschieben",
+  "cmd.panel.sash.up": "Panel-Trennlinie nach oben verschieben",
+  "cmd.panel.toggle": "Fokussiertes Panel ein- oder ausklappen",
   "cmd.parameters_add": "Benutzerparameter hinzufügen",
   "cmd.parameters_change": "Parameter ändern",
   "cmd.parameters_comment": "Parameter kommentieren",
@@ -1177,6 +1188,7 @@
   "cmd.sketch.construction_line.tangent_external": "Tangente durch äußeren Punkt",
   "cmd.sketch.construction_line.tangent_two": "Gemeinsame Tangente",
   "cmd.sketch.construction_line.vertical": "Vertikale Konstruktionslinie",
+  "cmd.sketch.replace": "Skizze ersetzen",
   "cmd.sketch_arc3d": "3D-Bogen",
   "cmd.sketch_arc_center_point": "Mittelpunkt-Kreisbogen",
   "cmd.sketch_arc_tangent": "Tangentialbogen",
@@ -1819,6 +1831,7 @@
   "help.view.visual_style": "Schaltet um, wie das Modell gezeichnet wird: schattiert mit oder ohne Kanten, Drahtmodell oder mit verdeckten Kanten. Drahtmodell zum Hineinschauen, schattiert für ein sauberes Bild.",
   "history.sketch_under_constrained": "Unterbestimmt ({count} Freiheitsgrade)",
   "history.sketch_under_constrained_one": "Unterbestimmt ({count} Freiheitsgrad)",
+  "hole_folder.applies_to": "Änderungen gelten für die {count} Bohrungen in {folder}; jede behält ihre Position.",
   "hole_presets.confirm_delete": "Löschen bestätigen",
   "hole_presets.delete": "Löschen",
   "hole_presets.delete_prompt": "Möchten Sie diese persönliche Vorlage wirklich löschen? Bereits vorhandene Bohrungen bleiben unverändert.",
@@ -2302,6 +2315,8 @@
   "prefs.bottom_centre": "Unten mittig",
   "prefs.bottom_right": "Unten rechts",
   "prefs.browser": "Browser",
+  "prefs.browser_body_features": "Features unter Körpern",
+  "prefs.browser_body_features_note": "Jeder Körper im Browser lässt sich aufklappen und zeigt die Features der Zeitleiste, die ihn erzeugt haben, in deren Reihenfolge.",
   "prefs.browser_components_open": "Komponenten zu Beginn aufgeklappt",
   "prefs.browser_components_open_note": "Jede Komponente im Browser ist wie bisher von Anfang an aufgeklappt, statt zugeklappt zu bleiben, bis du sie aufklappst.",
   "prefs.browser_eye_left": "Auge neben dem Aufklapppfeil",
@@ -2342,7 +2357,11 @@
   "prefs.design_tools.degrees": "Grad",
   "prefs.design_tools.double_click_help": "Oder zum Bearbeiten einer verknüpften Komponente an Ort und Stelle.",
   "prefs.design_tools.ghost": "Alte Position verschobener Teile als Geisterbild zeigen",
+  "prefs.design_tools.hole_group": "Gemeinsam erstellte Bohrungen gruppieren",
+  "prefs.design_tools.hole_group_help": "In einem Schritt erstellte Bohrungen teilen sich einen Ordner im Verlauf, zunächst geschlossen; öffnen Sie ihn, um eine Bohrung einzeln zu bearbeiten.",
   "prefs.design_tools.hole_moves_help": "Erneutes Auswählen der Fläche verschiebt die Bohrung, statt sie zu entfernen.",
+  "prefs.design_tools.hole_several": "Mehrere Bohrungen auf einer Fläche",
+  "prefs.design_tools.hole_several_help": "Eine Auswahl an anderer Stelle der Fläche fügt eine weitere Bohrung hinzu; die Auswahl einer Bohrung entfernt sie.",
   "prefs.design_tools.hole_snaps_help": "Die Mitte einer Fläche und die Mittelpunkte ihrer kreisförmigen Kanten.",
   "prefs.design_tools.imported_files": "Importierte Dateien",
   "prefs.design_tools.note": "Hinweis",
@@ -2424,6 +2443,8 @@
   "prefs.history": "Verlauf",
   "prefs.history_bar_groups": "Verlaufsleiste in Gruppen falten",
   "prefs.history_bar_groups_note": "In einem langen Verlauf wird eine Folge von Features einer Komponente zu einem Chip gefaltet, und Merkmalsordner beginnen gefaltet. Eine eingefügte STEP-Baugruppe kommt in einen Group-Ordner. Aus zeigt jedes Feature, öffnet Ordner und legt keinen Ordner an.",
+  "prefs.history_folder_kind_icon": "Ordnersymbol aus seinen Features",
+  "prefs.history_folder_kind_icon_note": "Ein Ordner im Verlauf, dessen Features alle von einer Art sind, zeigt deren Symbol.",
   "prefs.history_group_joints": "Gelenke im Verlauf gruppieren",
   "prefs.history_group_joints_note": "Zwei oder mehr Gelenke erscheinen als eine Schaltfläche mit ihrer Anzahl; ein Klick zeigt jedes einzeln. Aus zeigt jedes Gelenk einzeln.",
   "prefs.history_origin_bodies": "Ursprung und Körper oben zeigen",
@@ -2590,6 +2611,8 @@
   "prefs.select_other_hidden": "Verborgene Geometrie mit „Andere auswählen“ auswählen",
   "prefs.select_other_hidden_help": "Ein: Verborgene Körper, Skizzen und verdeckte Kanten nahe dem Zeiger einbeziehen. Aus: Die ursprüngliche Liste sichtbarer Geometrie direkt unter dem Zeiger verwenden.",
   "prefs.selecting": "Auswahl",
+  "prefs.shared_panel_layout": "Gemeinsames Panellayout verwenden",
+  "prefs.shared_panel_layout_help": "Browser, Verlauf und Assistent in verschiebbaren Panels anzeigen. Die Änderung wird beim Anwenden der Einstellungen wirksam.",
   "prefs.shift": "Umschalt",
   "prefs.shift_add_ctrl_toggle": "Umschalt fügt nur hinzu; Strg / Cmd schaltet die Auswahl um",
   "prefs.shift_add_note": "Aktiviert: Umschalt fügt Elemente zur Auswahl hinzu, Strg / Cmd schaltet ihre Auswahl um. Deaktiviert (Standard): Beide Tasten schalten die Auswahl um.",
@@ -3128,7 +3151,7 @@
   "render.cpu_opaque_required": "CPU-Raytracing benötigt einen undurchsichtigen Hintergrund. Entfernen Sie das Häkchen bei „Transparenter Hintergrund“, um fortzufahren.",
   "render.cpu_options_pending": "Dieses CPU-Bedienfeld kann Emission, Oberflächeneffekte, Glas oder Anisotropie noch nicht bearbeiten. Entfernen Sie diese API-Optionen, bevor Sie es verwenden.",
   "render.cpu_path_depth": "Pfadtiefe",
-  "render.cpu_path_help": "Berechnet Licht, das zwischen undurchsichtigen Flächen und durch unterstützte Glasformen läuft. Erfordert progressives Rendern und Raytracing-Schatten. Die Pfadtiefe zählt beleuchtete Flächen, Glasgrenzen und Streuereignisse ab dem ersten Treffer (1–16). Tiefe 1 liefert direkte Beleuchtung auf undurchsichtigen Flächen; höhere Werte erlauben mehr Reflexionen oder Glasdurchgänge und können länger dauern. Für eigene Reflexionen oder Anisotropie die indirekte Beleuchtung ausschalten.",
+  "render.cpu_path_help": "Berechnet Licht, das zwischen undurchsichtigen Flächen und durch unterstützte Glasformen läuft. Erfordert progressives Rendern und Raytracing-Schatten. Die Pfadtiefe zählt beleuchtete Flächen, Glasgrenzen und Streuereignisse ab dem ersten Treffer (1–64). Tiefe 1 liefert direkte Beleuchtung auf undurchsichtigen Flächen; höhere Werte erlauben mehr Reflexionen oder Glasdurchgänge und können länger dauern. Für eigene Reflexionen oder Anisotropie die indirekte Beleuchtung ausschalten.",
   "render.cpu_path_lighting": "Indirekte Beleuchtung",
   "render.cpu_path_optics_reason": "Die Einstellungen bleiben erhalten. Für eigene Reflexionen oder Anisotropie die indirekte Beleuchtung ausschalten.",
   "render.cpu_point": "Punktlicht",
@@ -5240,6 +5263,7 @@
   "ui.heading_plastic": "PLASTIK",
   "ui.heading_position": "POSITION",
   "ui.heading_prepare": "VORBEREITEN",
+  "ui.heading_press_pull": "DRÜCKEN/ZIEHEN",
   "ui.heading_rectangular_pattern": "RECHTECKMUSTER",
   "ui.heading_revolve": "DREHEN",
   "ui.heading_right": "RECHTS",
@@ -5579,6 +5603,8 @@
   "ui.profiles": "Profile",
   "ui.project": "Projizieren",
   "ui.project_face_edges_sketch": "Flächenkanten in neue Skizzen projizieren",
+  "ui.project_references_construction": "Referenzen als Konstruktionsgeometrie projizieren",
+  "ui.project_references_construction_note": "Projizieren, Schneiden, 3D-Geometrie einbeziehen und die Flächenkanten einer neuen Skizze auf einer Fläche erzeugen Konstruktionsgeometrie: Bezüge zum Zeichnen, die nicht zu Profilen gehören. Sie bleiben mit dem Modell verknüpft.",
   "ui.properties": "Eigenschaften",
   "ui.properties.copy_matrix": "Matrix kopieren",
   "ui.properties.first_moments": "Statische Momente",
@@ -5620,6 +5646,8 @@
   "ui.renderer": "Renderer",
   "ui.repeat": "Wiederholen",
   "ui.repeat_nothing": "Noch nichts zu wiederholen: Starten Sie zuerst ein Werkzeug oder einen Dialog.",
+  "ui.replace_sketch.from_file": "Aus einer Konstruktionsdatei…",
+  "ui.replace_sketch.no_sketches": "Diese Konstruktion enthält keine Skizze",
   "ui.replace_with_link_done": "Die Kopien sind jetzt Platzierungen des verknüpften Designs.",
   "ui.report_a_bug": "Fehler melden",
   "ui.report_characters_left_one": "{count} Zeichen übrig",

assets/locales/en.json

@@ -265,6 +265,7 @@
   "Edge": "Edge",
   "Edges": "Edges",
   "Edit": "Edit",
+  "Edit Holes": "Edit Holes",
   "Edit Profile Sketch": "Edit Profile Sketch",
   "Edit shortcuts": "Edit shortcuts",
   "Enable rule": "Enable rule",
@@ -1206,6 +1207,7 @@
   "cmd.material_properties_directional": "Directional Elastic Modulus",
   "cmd.material_properties_validate": "Validate Physical Material Data",
   "cmd.mesh_convert": "Convert Mesh",
+  "cmd.model_body_features": "List Body Features",
   "cmd.model_edges": "List Edges",
   "cmd.model_faces": "List Faces",
   "cmd.model_threads": "List Threads",
@@ -1234,8 +1236,11 @@
   "cmd.panel.dismiss": "Dismiss Panel Peek",
   "cmd.panel.float": "Float Panel",
   "cmd.panel.focus": "Focus Panel",
+  "cmd.panel.focus.next": "Focus Next Panel",
+  "cmd.panel.focus.previous": "Focus Previous Panel",
   "cmd.panel.list": "List Panels",
   "cmd.panel.move": "Move Panel",
+  "cmd.panel.move.next_zone": "Move Panel to Next Zone",
   "cmd.panel.native_close": "Redock Native Panel Section",
   "cmd.panel.open": "Open Panel",
   "cmd.panel.peek": "Peek Collapsed Panel",
@@ -1243,6 +1248,12 @@
   "cmd.panel.reset_pair": "Reset Panel Sash",
   "cmd.panel.resize": "Resize Panel Section",
   "cmd.panel.resize_pair": "Resize Panel Sash",
+  "cmd.panel.sash.down": "Resize Panel Sash Down",
+  "cmd.panel.sash.left": "Resize Panel Sash Left",
+  "cmd.panel.sash.reset": "Reset Focused Panel Sash",
+  "cmd.panel.sash.right": "Resize Panel Sash Right",
+  "cmd.panel.sash.up": "Resize Panel Sash Up",
+  "cmd.panel.toggle": "Toggle Focused Panel",
   "cmd.parameters_add": "Add User Parameter",
   "cmd.parameters_change": "Change Parameters",
   "cmd.parameters_comment": "Comment Parameter",
@@ -1366,6 +1377,7 @@
   "cmd.sketch.construction_line.tangent_external": "Tangent through External Point",
   "cmd.sketch.construction_line.tangent_two": "Common Tangent",
   "cmd.sketch.construction_line.vertical": "Vertical Construction Line",
+  "cmd.sketch.replace": "Replace Sketch",
   "cmd.sketch_arc3d": "3D Arc",
   "cmd.sketch_arc_center_point": "Center Point Arc",
   "cmd.sketch_arc_tangent": "Tangent Arc",
@@ -2016,6 +2028,7 @@
   "help.view.visual_style": "Switches how the model is drawn: shaded with or without edges, wireframe, or with hidden edges. Use wireframe to see inside, shaded for a clean look.",
   "history.sketch_under_constrained": "Under constrained ({count} degrees of freedom)",
   "history.sketch_under_constrained_one": "Under constrained ({count} degree of freedom)",
+  "hole_folder.applies_to": "Changes apply to the {count} holes in {folder}; each keeps its place.",
   "hole_presets.confirm_delete": "Confirm delete",
   "hole_presets.delete": "Delete",
   "hole_presets.delete_prompt": "Delete this personal preset? Existing holes are unchanged.",
@@ -2515,6 +2528,8 @@
   "prefs.bottom_centre": "Bottom center",
   "prefs.bottom_right": "Bottom right",
   "prefs.browser": "Browser",
+  "prefs.browser_body_features": "Features under bodies",
+  "prefs.browser_body_features_note": "Each body in the browser folds open on the timeline features that built it, in timeline order.",
   "prefs.browser_components_open": "Components start open",
   "prefs.browser_components_open_note": "Every component in the browser starts open, as before, instead of closed until you open it.",
   "prefs.browser_eye_left": "Eye beside the fold arrow",
@@ -2555,7 +2570,11 @@
   "prefs.design_tools.degrees": "Degrees",
   "prefs.design_tools.double_click_help": "Or to edit a linked one in place.",
   "prefs.design_tools.ghost": "Show moved parts' old place as a ghost",
+  "prefs.design_tools.hole_group": "Group holes made together",
+  "prefs.design_tools.hole_group_help": "Holes made in one go share a folder in History, closed at first; open it to edit a hole on its own.",
   "prefs.design_tools.hole_moves_help": "Picking the face again moves the hole instead of removing it.",
+  "prefs.design_tools.hole_several": "Several holes on one face",
+  "prefs.design_tools.hole_several_help": "Picking elsewhere on a face adds another hole; picking a hole removes it.",
   "prefs.design_tools.hole_snaps_help": "The middle of a face and the centers of its round edges.",
   "prefs.design_tools.imported_files": "Imported files",
   "prefs.design_tools.note": "Note",
@@ -2637,6 +2656,8 @@
   "prefs.history": "History",
   "prefs.history_bar_groups": "Fold the History bar into groups",
   "prefs.history_bar_groups_note": "In a long history, a run of one component's features folds into one chip, and feature folders start folded. An inserted STEP assembly goes into a Group folder. Off shows each feature, starts folders open and makes no folder.",
+  "prefs.history_folder_kind_icon": "Folder icon from its features",
+  "prefs.history_folder_kind_icon_note": "A History folder whose features are all of one kind shows their icon.",
   "prefs.history_group_joints": "Group joints in the History",
   "prefs.history_group_joints_note": "Two or more joints show as one button with their count, and a click shows each one. Off shows each joint.",
   "prefs.history_origin_bodies": "Show origin and bodies at the top",
@@ -2830,6 +2851,8 @@
   "prefs.select_other_hidden": "Select hidden geometry with Select Other",
   "prefs.select_other_hidden_help": "On: include hidden bodies, sketches and occluded edges near the pointer. Off: use the original list of visible geometry under the pointer.",
   "prefs.selecting": "Selecting",
+  "prefs.shared_panel_layout": "Use shared panel layout",
+  "prefs.shared_panel_layout_help": "Show the existing Browser, History and Assistant in movable panels. The change takes effect when preferences are applied.",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift adds only; Ctrl / Cmd toggles",
   "prefs.shift_add_note": "On: Shift adds, Ctrl / Cmd toggles. Off (default): both toggle.",
@@ -3374,7 +3397,7 @@
   "render.cpu_opaque_required": "CPU ray tracing needs an opaque background. Clear Transparent background to continue.",
   "render.cpu_options_pending": "This CPU panel cannot edit emission, surface effects, glass or anisotropy yet. Clear those API options before using it.",
   "render.cpu_path_depth": "Path depth",
-  "render.cpu_path_help": "Adds light bouncing between opaque surfaces and through supported Glass shapes. Requires progressive rendering and traced shadows. Path depth counts shaded surfaces, Glass boundaries and scattering events, starting with the first hit (1–16). Depth 1 gives direct lighting on opaque surfaces; higher values allow more bounces or Glass crossings and may take longer. Turn off Indirect lighting to use custom reflections or anisotropy.",
+  "render.cpu_path_help": "Adds light bouncing between opaque surfaces and through supported Glass shapes. Requires progressive rendering and traced shadows. Path depth counts shaded surfaces, Glass boundaries and scattering events, starting with the first hit (1–64). Depth 1 gives direct lighting on opaque surfaces; higher values allow more bounces or Glass crossings and may take longer. Turn off Indirect lighting to use custom reflections or anisotropy.",
   "render.cpu_path_lighting": "Indirect lighting",
   "render.cpu_path_optics_reason": "Your settings are kept. Turn off Indirect lighting to use custom reflections or anisotropy.",
   "render.cpu_point": "Point light",
@@ -5520,6 +5543,7 @@
   "ui.heading_plastic": "PLASTIC",
   "ui.heading_position": "POSITION",
   "ui.heading_prepare": "PREPARE",
+  "ui.heading_press_pull": "PRESS PULL",
   "ui.heading_rectangular_pattern": "RECTANGULAR PATTERN",
   "ui.heading_revolve": "REVOLVE",
   "ui.heading_right": "RIGHT",
@@ -5863,6 +5887,8 @@
   "ui.profiles": "Profiles",
   "ui.project": "Project",
   "ui.project_face_edges_sketch": "Project face edges into new sketches",
+  "ui.project_references_construction": "Project references as construction geometry",
+  "ui.project_references_construction_note": "Project, Intersect, Include 3D Geometry and the face edges of a new sketch on a face make construction geometry: references to draw against, left out of profiles. They stay linked to the model.",
   "ui.properties": "Properties",
   "ui.properties.copy_matrix": "Copy matrix",
   "ui.properties.first_moments": "First moments",
@@ -5906,6 +5932,8 @@
   "ui.renderer": "Renderer",
   "ui.repeat": "Repeat",
   "ui.repeat_nothing": "Nothing to repeat yet: start a tool or dialog first.",
+  "ui.replace_sketch.from_file": "From a Design File…",
+  "ui.replace_sketch.no_sketches": "That design has no sketch to take",
   "ui.replace_with_link_done": "The copies are now placements of the linked design.",
   "ui.report_a_bug": "Report a bug",
   "ui.report_characters_left_one": "{count} character left",

assets/locales/fr.json

@@ -1000,6 +1000,7 @@
   "cmd.material_properties_directional": "Module d'élasticité directionnel",
   "cmd.material_properties_validate": "Valider les données du matériau physique",
   "cmd.mesh_convert": "Convertir le maillage",
+  "cmd.model_body_features": "Lister les fonctions du corps",
   "cmd.model_edges": "Lister les arêtes",
   "cmd.model_faces": "Lister les faces",
   "cmd.model_threads": "Lister les filetages",
@@ -1139,6 +1140,7 @@
   "cmd.sketch.construction_line.tangent_external": "Tangente passant par un point extérieur",
   "cmd.sketch.construction_line.tangent_two": "Tangente commune",
   "cmd.sketch.construction_line.vertical": "Droite de construction verticale",
+  "cmd.sketch.replace": "Remplacer l’esquisse",
   "cmd.sketch_arc3d": "Arc 3D",
   "cmd.sketch_arc_center_point": "Arc par centre",
   "cmd.sketch_arc_tangent": "Arc tangent",
@@ -2163,6 +2165,8 @@
   "prefs.bottom_centre": "Bas centre",
   "prefs.bottom_right": "Bas droite",
   "prefs.browser": "Navigateur",
+  "prefs.browser_body_features": "Fonctions sous les corps",
+  "prefs.browser_body_features_note": "Chaque corps du navigateur se déplie sur les fonctions de l'historique qui l'ont construit, dans l'ordre de l'historique.",
   "prefs.browser_components_open": "Composants dépliés au départ",
   "prefs.browser_components_open_note": "Chaque composant du navigateur commence déplié, comme avant, au lieu de rester replié jusqu'à ce que vous le dépliiez.",
   "prefs.browser_eye_left": "Œil à côté de la flèche de dépliage",
@@ -5015,6 +5019,8 @@
   "ui.renderer": "Moteur de rendu",
   "ui.repeat": "Répéter",
   "ui.repeat_nothing": "Rien à répéter pour l'instant : lancer d'abord un outil ou une boîte de dialogue.",
+  "ui.replace_sketch.from_file": "Depuis un fichier de conception…",
+  "ui.replace_sketch.no_sketches": "Cette conception ne contient aucune esquisse",
   "ui.replace_with_link_done": "Les copies sont maintenant des placements de la conception liée.",
   "ui.report_a_bug": "Signaler un bug",
   "ui.reset": "Réinitialiser",

assets/locales/he.json

@@ -265,6 +265,7 @@
   "Edge": "מקצוע",
   "Edges": "מקצועות",
   "Edit": "עריכה",
+  "Edit Holes": "עריכת חורים",
   "Edit Profile Sketch": "עריכת סקיצת הפרופיל",
   "Edit shortcuts": "עריכת קיצורי דרך",
   "Enable rule": "הפעלת הכלל",
@@ -1206,6 +1207,7 @@
   "cmd.material_properties_directional": "מודול אלסטיות כיווני",
   "cmd.material_properties_validate": "אימות נתוני חומר פיזיקלי",
   "cmd.mesh_convert": "המרת רשת משולשים",
+  "cmd.model_body_features": "הצגת פיצ'רים של גוף",
   "cmd.model_edges": "רשימת מקצועות",
   "cmd.model_faces": "רשימת פאות",
   "cmd.model_threads": "רשימת הברגות",
@@ -1234,8 +1236,11 @@
   "cmd.panel.dismiss": "סגירת תצוגה זמנית של חלונית",
   "cmd.panel.float": "הצפת חלונית",
   "cmd.panel.focus": "מיקוד חלונית",
+  "cmd.panel.focus.next": "מיקוד בלוח הבא",
+  "cmd.panel.focus.previous": "מיקוד בלוח הקודם",
   "cmd.panel.list": "הצגת רשימת חלוניות",
   "cmd.panel.move": "העברת חלונית",
+  "cmd.panel.move.next_zone": "העברת הלוח לאזור הבא",
   "cmd.panel.native_close": "עיגון מחדש של מקטע חלונית מחלון נפרד",
   "cmd.panel.open": "פתיחת חלונית",
   "cmd.panel.peek": "הצגה זמנית של חלונית מכווצת",
@@ -1243,6 +1248,12 @@
   "cmd.panel.reset_pair": "איפוס מפריד חלוניות",
   "cmd.panel.resize": "שינוי גודל מקטע חלונית",
   "cmd.panel.resize_pair": "הזזת מפריד חלוניות",
+  "cmd.panel.sash.down": "הזזת מפריד הלוח למטה",
+  "cmd.panel.sash.left": "הזזת מפריד הלוח שמאלה",
+  "cmd.panel.sash.reset": "איפוס מפריד הלוח שבמיקוד",
+  "cmd.panel.sash.right": "הזזת מפריד הלוח ימינה",
+  "cmd.panel.sash.up": "הזזת מפריד הלוח למעלה",
+  "cmd.panel.toggle": "שינוי מצב הכיווץ של הלוח שבמיקוד",
   "cmd.parameters_add": "הוספת פרמטר משתמש",
   "cmd.parameters_change": "שינוי פרמטרים",
   "cmd.parameters_comment": "הערה לפרמטר",
@@ -1366,6 +1377,7 @@
   "cmd.sketch.construction_line.tangent_external": "משיק דרך נקודה חיצונית",
   "cmd.sketch.construction_line.tangent_two": "משיק משותף",
   "cmd.sketch.construction_line.vertical": "ישר עזר אנכי",
+  "cmd.sketch.replace": "החלפת סקיצה",
   "cmd.sketch_arc3d": "קשת תלת־ממדית",
   "cmd.sketch_arc_center_point": "קשת מרכז ונקודה",
   "cmd.sketch_arc_tangent": "קשת משיקה",
@@ -2016,6 +2028,7 @@
   "help.view.visual_style": "החלפת אופן הציור של המודל: מוצלל עם מקצועות או בלעדיהם, מסגרת תיל, או עם מקצועות מוסתרים. מסגרת תיל מאפשרת לראות פנימה, ומוצלל נותן מראה נקי.",
   "history.sketch_under_constrained": "אילוצים חסרים ({count} דרגות חופש)",
   "history.sketch_under_constrained_one": "אילוצים חסרים (דרגת חופש {count})",
+  "hole_folder.applies_to": "השינויים חלים על {count} החורים ב-{folder}; כל חור שומר על מיקומו.",
   "hole_presets.confirm_delete": "אישור מחיקה",
   "hole_presets.delete": "מחיקה",
   "hole_presets.delete_prompt": "למחוק את ההגדרה המוכנה האישית הזו? חורים קיימים לא ישתנו.",
@@ -2515,6 +2528,8 @@
   "prefs.bottom_centre": "למטה במרכז",
   "prefs.bottom_right": "למטה מימין",
   "prefs.browser": "עץ התכן",
+  "prefs.browser_body_features": "פיצ'רים מתחת לגופים",
+  "prefs.browser_body_features_note": "כל גוף בדפדפן נפתח ומציג את הפיצ'רים מציר הזמן שבנו אותו, לפי סדר ציר הזמן.",
   "prefs.browser_components_open": "רכיבים פתוחים מההתחלה",
   "prefs.browser_components_open_note": "כל רכיב בעץ התכן מתחיל פתוח, כמו קודם, במקום סגור עד שתפתח אותו.",
   "prefs.browser_eye_left": "סמל העין ליד חץ הקיפול",
@@ -2555,7 +2570,11 @@
   "prefs.design_tools.degrees": "מעלות",
   "prefs.design_tools.double_click_help": "או לעריכת רכיב מקושר במקומו.",
   "prefs.design_tools.ghost": "הצגת המיקום הקודם של חלקים שהוזזו כרפאים",
+  "prefs.design_tools.hole_group": "קיבוץ חורים שנוצרו יחד",
+  "prefs.design_tools.hole_group_help": "חורים שנוצרו בפעולה אחת חולקים תיקייה בהיסטוריה, סגורה בהתחלה; פתחו אותה כדי לערוך חור בנפרד.",
   "prefs.design_tools.hole_moves_help": "בחירה חוזרת בפאה מזיזה את החור במקום להסירו.",
+  "prefs.design_tools.hole_several": "כמה חורים בפאה אחת",
+  "prefs.design_tools.hole_several_help": "בחירה במקום אחר בפאה מוסיפה חור נוסף; בחירה בחור מסירה אותו.",
   "prefs.design_tools.hole_snaps_help": "אמצע הפאה ומרכזי הקצוות העגולים שלה.",
   "prefs.design_tools.imported_files": "קבצים מיובאים",
   "prefs.design_tools.note": "הערה",
@@ -2637,6 +2656,8 @@
   "prefs.history": "ציר הזמן",
   "prefs.history_bar_groups": "קיפול סרגל ציר הזמן לקבוצות",
   "prefs.history_bar_groups_note": "בציר זמן ארוך, רצף פיצ'רים של רכיב אחד מתקפל לשבב אחד, ותיקיות פיצ'רים מתחילות מקופלות. מכלול STEP שהוכנס נכנס לתיקיית Group. כשהאפשרות כבויה, כל פיצ'ר מוצג, התיקיות מתחילות פתוחות ולא נוצרת תיקייה.",
+  "prefs.history_folder_kind_icon": "סמל התיקייה לפי התכונות שבה",
+  "prefs.history_folder_kind_icon_note": "תיקייה בהיסטוריה שכל התכונות בה מאותו סוג מציגה את הסמל שלהן.",
   "prefs.history_group_joints": "קיבוץ מפרקים בציר הזמן",
   "prefs.history_group_joints_note": "שני מפרקים או יותר מוצגים ככפתור אחד עם מספרם, ולחיצה מציגה כל אחד מהם. כשהאפשרות כבויה, כל מפרק מוצג בנפרד.",
   "prefs.history_origin_bodies": "הצגת הראשית והגופים למעלה",
@@ -2830,6 +2851,8 @@
   "prefs.select_other_hidden": "בחירת גאומטריה מוסתרת באמצעות בחירה אחרת",
   "prefs.select_other_hidden_help": "מופעל: כולל גופים, סקיצות וקצוות מוסתרים בקרבת הסמן. כבוי: שימוש ברשימה המקורית של גאומטריה גלויה מתחת לסמן.",
   "prefs.selecting": "בחירה",
+  "prefs.shared_panel_layout": "שימוש בפריסת הלוחות המשותפת",
+  "prefs.shared_panel_layout_help": "הצגת הדפדפן, ההיסטוריה והעוזר בלוחות ניתנים להזזה. השינוי ייכנס לתוקף לאחר החלת ההעדפות.",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift מוסיף בלבד; Ctrl / Cmd מחליף מצב",
   "prefs.shift_add_note": "כשפועל: Shift מוסיף, Ctrl / Cmd מחליף מצב. כשכבוי (ברירת מחדל): שניהם מחליפים מצב.",
@@ -3374,7 +3397,7 @@
   "render.cpu_opaque_required": "מעקב קרניים ב־CPU דורש רקע אטום. יש לבטל את „רקע שקוף” כדי להמשיך.",
   "render.cpu_options_pending": "לוח CPU זה עדיין אינו יכול לערוך פליטה, אפקטי משטח, זכוכית או אנאיזוטרופיה. יש לנקות את אפשרויות ה־API האלה לפני השימוש בו.",
   "render.cpu_path_depth": "עומק מסלול",
-  "render.cpu_path_help": "מחשבת אור שמוחזר בין משטחים אטומים ועובר דרך צורות זכוכית נתמכות. נדרשים רינדור הדרגתי וצללים במעקב קרניים. עומק המסלול סופר משטחים מוצללים, גבולות זכוכית ואירועי פיזור החל מהמפגש הראשון (1–16). עומק 1 נותן תאורה ישירה למשטחים אטומים; ערכים גבוהים מאפשרים יותר החזרות או מעברים בזכוכית ועשויים לדרוש יותר זמן. יש לכבות תאורה עקיפה כדי להשתמש בהשתקפויות מותאמות או באנאיזוטרופיה.",
+  "render.cpu_path_help": "מחשבת אור שמוחזר בין משטחים אטומים ועובר דרך צורות זכוכית נתמכות. נדרשים רינדור הדרגתי וצללים במעקב קרניים. עומק המסלול סופר משטחים מוצללים, גבולות זכוכית ואירועי פיזור החל מהמפגש הראשון (1–64). עומק 1 נותן תאורה ישירה למשטחים אטומים; ערכים גבוהים מאפשרים יותר החזרות או מעברים בזכוכית ועשויים לדרוש יותר זמן. יש לכבות תאורה עקיפה כדי להשתמש בהשתקפויות מותאמות או באנאיזוטרופיה.",
   "render.cpu_path_lighting": "תאורה עקיפה",
   "render.cpu_path_optics_reason": "ההגדרות שלך נשמרות. יש לכבות תאורה עקיפה כדי להשתמש בהשתקפויות מותאמות או באנאיזוטרופיה.",
   "render.cpu_point": "אור נקודתי",
@@ -5520,6 +5543,7 @@
   "ui.heading_plastic": "פלסטיק",
   "ui.heading_position": "מיקום",
   "ui.heading_prepare": "הכנה",
+  "ui.heading_press_pull": "דחיפה/משיכה",
   "ui.heading_rectangular_pattern": "מערך מלבני",
   "ui.heading_revolve": "סיבוב",
   "ui.heading_right": "ימין",
@@ -5863,6 +5887,8 @@
   "ui.profiles": "פרופילים",
   "ui.project": "הטלה",
   "ui.project_face_edges_sketch": "הטלת מקצועות הפאה לסקיצות חדשות",
+  "ui.project_references_construction": "הטלת הפניות כגאומטריית עזר",
+  "ui.project_references_construction_note": "הטלה, חיתוך, הכללת גאומטריה תלת־ממדית ומקצועות הפאה של סקיצה חדשה על פאה יוצרים גאומטריית עזר: הפניות לשרטוט שאינן נכללות בפרופילים. הן נשארות מקושרות למודל.",
   "ui.properties": "מאפיינים",
   "ui.properties.copy_matrix": "העתקת המטריצה",
   "ui.properties.first_moments": "מומנטים ראשונים",
@@ -5906,6 +5932,8 @@
   "ui.renderer": "מנוע גרפי",
   "ui.repeat": "חזרה",
   "ui.repeat_nothing": "אין עדיין מה לחזור עליו: התחל קודם כלי או תיבת דו־שיח.",
+  "ui.replace_sketch.from_file": "מקובץ תכנון…",
+  "ui.replace_sketch.no_sketches": "בתכנון הזה אין סקיצה לקחת",
   "ui.replace_with_link_done": "העותקים הם עכשיו מיקומים של התכן המקושר.",
   "ui.report_a_bug": "דיווח על באג",
   "ui.report_characters_left_one": "תווים שנותרו: {count}",

assets/locales/ja.json

@@ -265,6 +265,7 @@
   "Edge": "エッジ",
   "Edges": "エッジ",
   "Edit": "編集",
+  "Edit Holes": "穴を編集",
   "Edit Profile Sketch": "プロファイルスケッチを編集",
   "Edit shortcuts": "ショートカットを編集",
   "Enable rule": "ルールを有効化",
@@ -1206,6 +1207,7 @@
   "cmd.material_properties_directional": "方向別弾性率",
   "cmd.material_properties_validate": "物理材料データを検証",
   "cmd.mesh_convert": "メッシュを変換",
+  "cmd.model_body_features": "ボディのフィーチャーを一覧表示",
   "cmd.model_edges": "エッジを一覧表示",
   "cmd.model_faces": "面を一覧表示",
   "cmd.model_threads": "ねじを一覧表示",
@@ -1234,8 +1236,11 @@
   "cmd.panel.dismiss": "パネルの一時表示を閉じる",
   "cmd.panel.float": "パネルをフロート表示",
   "cmd.panel.focus": "パネルにフォーカス",
+  "cmd.panel.focus.next": "次のパネルにフォーカス",
+  "cmd.panel.focus.previous": "前のパネルにフォーカス",
   "cmd.panel.list": "パネルを一覧表示",
   "cmd.panel.move": "パネルを移動",
+  "cmd.panel.move.next_zone": "パネルを次の領域に移動",
   "cmd.panel.native_close": "別ウィンドウのパネルを再ドッキング",
   "cmd.panel.open": "パネルを開く",
   "cmd.panel.peek": "折りたたんだパネルを一時表示",
@@ -1243,6 +1248,12 @@
   "cmd.panel.reset_pair": "パネルの区切りをリセット",
   "cmd.panel.resize": "パネルのセクションのサイズを変更",
   "cmd.panel.resize_pair": "パネルの区切りを移動",
+  "cmd.panel.sash.down": "パネルの区切りを下に移動",
+  "cmd.panel.sash.left": "パネルの区切りを左に移動",
+  "cmd.panel.sash.reset": "フォーカス中のパネルの区切りをリセット",
+  "cmd.panel.sash.right": "パネルの区切りを右に移動",
+  "cmd.panel.sash.up": "パネルの区切りを上に移動",
+  "cmd.panel.toggle": "フォーカス中のパネルの折りたたみを切り替え",
   "cmd.parameters_add": "ユーザー パラメータを追加",
   "cmd.parameters_change": "パラメータを変更",
   "cmd.parameters_comment": "パラメータにコメントを付与",
@@ -1366,6 +1377,7 @@
   "cmd.sketch.construction_line.tangent_external": "外部点を通る接線",
   "cmd.sketch.construction_line.tangent_two": "共通接線",
   "cmd.sketch.construction_line.vertical": "垂直補助直線",
+  "cmd.sketch.replace": "スケッチを置き換え",
   "cmd.sketch_arc3d": "3D 円弧",
   "cmd.sketch_arc_center_point": "中心点円弧",
   "cmd.sketch_arc_tangent": "正接円弧",
@@ -2016,6 +2028,7 @@
   "help.view.visual_style": "モデルの描画方法（エッジ付きまたはなしのシェード、ワイヤーフレーム、隠線付き）を切り替えます。内部を見るにはワイヤーフレーム、すっきり見せるにはシェードを使います。",
   "history.sketch_under_constrained": "拘束不足（自由度 {count}）",
   "history.sketch_under_constrained_one": "拘束不足（自由度 {count}）",
+  "hole_folder.applies_to": "変更は {folder} の {count} 個の穴に適用されます。各穴の位置はそのままです。",
   "hole_presets.confirm_delete": "削除を確認",
   "hole_presets.delete": "削除",
   "hole_presets.delete_prompt": "この個人用プリセットを削除しますか？既存の穴は変更されません。",
@@ -2515,6 +2528,8 @@
   "prefs.bottom_centre": "下中央",
   "prefs.bottom_right": "右下",
   "prefs.browser": "ブラウザー",
+  "prefs.browser_body_features": "ボディの下にフィーチャー",
+  "prefs.browser_body_features_note": "ブラウザーの各ボディを展開すると、そのボディを作ったタイムラインのフィーチャーがタイムライン順に表示されます。",
   "prefs.browser_components_open": "コンポーネントを最初から展開",
   "prefs.browser_components_open_note": "ブラウザーのすべてのコンポーネントを以前と同じく最初から展開して表示します。オフの場合は展開するまで折りたたまれています。",
   "prefs.browser_eye_left": "折りたたみ矢印の隣の目のアイコン",
@@ -2555,7 +2570,11 @@
   "prefs.design_tools.degrees": "度",
   "prefs.design_tools.double_click_help": "リンクされたコンポーネントをその場で編集することもできます。",
   "prefs.design_tools.ghost": "移動したパーツの元の位置をゴースト表示",
+  "prefs.design_tools.hole_group": "一緒に作成した穴をまとめる",
+  "prefs.design_tools.hole_group_help": "一度に作成した穴は履歴で1つのフォルダーにまとめられ、最初は閉じています。開くと穴を個別に編集できます。",
   "prefs.design_tools.hole_moves_help": "面をもう一度選ぶと穴を削除せずに移動します。",
+  "prefs.design_tools.hole_several": "1つの面に複数の穴",
+  "prefs.design_tools.hole_several_help": "面の別の場所を選ぶと穴を追加し、穴を選ぶとその穴を削除します。",
   "prefs.design_tools.hole_snaps_help": "面の中央と円形エッジの中心。",
   "prefs.design_tools.imported_files": "インポートしたファイル",
   "prefs.design_tools.note": "通知",
@@ -2637,6 +2656,8 @@
   "prefs.history": "履歴",
   "prefs.history_bar_groups": "履歴バーをグループにまとめる",
   "prefs.history_bar_groups_note": "長い履歴では、1つのコンポーネントの連続したフィーチャーを1つのチップにまとめ、フィーチャーフォルダは閉じた状態で始まります。挿入したSTEPアセンブリはGroupフォルダに入ります。オフにすると、各フィーチャーを表示し、フォルダは開いた状態で始まり、フォルダは作成されません。",
+  "prefs.history_folder_kind_icon": "中のフィーチャーのアイコンをフォルダーに使う",
+  "prefs.history_folder_kind_icon_note": "中のフィーチャーがすべて同じ種類の履歴フォルダーは、そのアイコンで表示されます。",
   "prefs.history_group_joints": "履歴でジョイントをまとめる",
   "prefs.history_group_joints_note": "2つ以上のジョイントを、数を添えた1つのボタンにまとめます。クリックすると各ジョイントを表示します。オフにすると各ジョイントを個別に表示します。",
   "prefs.history_origin_bodies": "原点とボディを先頭に表示",
@@ -2830,6 +2851,8 @@
   "prefs.select_other_hidden": "「他を選択」で非表示のジオメトリを選択",
   "prefs.select_other_hidden_help": "オン: ポインター付近の非表示のボディやスケッチ、遮られたエッジを含めます。オフ: ポインター直下の表示中のジオメトリだけを元のリストに表示します。",
   "prefs.selecting": "選択",
+  "prefs.shared_panel_layout": "共通のパネルレイアウトを使用",
+  "prefs.shared_panel_layout_help": "既存のブラウザー、履歴、アシスタントを移動可能なパネルに表示します。設定を適用すると変更が有効になります。",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift は追加のみ、Ctrl / Cmd は選択を切り替え",
   "prefs.shift_add_note": "オン：Shift は追加、Ctrl / Cmd は選択を切り替えます。オフ（既定）：どちらも選択を切り替えます。",
@@ -3374,7 +3397,7 @@
   "render.cpu_opaque_required": "CPU レイトレーシングには不透明な背景が必要です。透明な背景を解除してください。",
   "render.cpu_options_pending": "このCPUパネルでは、発光、表面効果、ガラス、異方性はまだ編集できません。使用前にそれらのAPIオプションを解除してください。",
   "render.cpu_path_depth": "パス深度",
-  "render.cpu_path_help": "不透明な面の間で反射し、対応するガラス形状を通る光を計算します。プログレッシブ描画とレイトレーシングの影が必要です。パス深度は最初の交点から、照明を計算する面、ガラス境界、散乱イベントを数えます（1～16）。深度1は不透明面の直接照明のみです。値を上げると反射やガラスの通過を増やせますが、時間がかかる場合があります。独自の反射設定や異方性を使うには間接照明をオフにしてください。",
+  "render.cpu_path_help": "不透明な面の間で反射し、対応するガラス形状を通る光を計算します。プログレッシブ描画とレイトレーシングの影が必要です。パス深度は最初の交点から、照明を計算する面、ガラス境界、散乱イベントを数えます（1～64）。深度1は不透明面の直接照明のみです。値を上げると反射やガラスの通過を増やせますが、時間がかかる場合があります。独自の反射設定や異方性を使うには間接照明をオフにしてください。",
   "render.cpu_path_lighting": "間接照明",
   "render.cpu_path_optics_reason": "設定は保持されます。独自の反射設定や異方性を使うには間接照明をオフにしてください。",
   "render.cpu_point": "点光源",
@@ -5520,6 +5543,7 @@
   "ui.heading_plastic": "プラスチック",
   "ui.heading_position": "配置",
   "ui.heading_prepare": "準備",
+  "ui.heading_press_pull": "プレス プル",
   "ui.heading_rectangular_pattern": "矩形パターン",
   "ui.heading_revolve": "回転",
   "ui.heading_right": "右側面",
@@ -5863,6 +5887,8 @@
   "ui.profiles": "プロファイル",
   "ui.project": "投影",
   "ui.project_face_edges_sketch": "新規スケッチに面のエッジを自動投影",
+  "ui.project_references_construction": "参照をコンストラクションジオメトリとして投影",
+  "ui.project_references_construction_note": "投影、交差、3D ジオメトリを含める、および面上の新規スケッチの面のエッジは、コンストラクションジオメトリになります。描画の参照用で、プロファイルには含まれません。モデルとのリンクは保たれます。",
   "ui.properties": "プロパティ",
   "ui.properties.copy_matrix": "行列をコピー",
   "ui.properties.first_moments": "一次モーメント",
@@ -5906,6 +5932,8 @@
   "ui.renderer": "レンダラー",
   "ui.repeat": "繰り返し",
   "ui.repeat_nothing": "まだ繰り返すものがありません。先にツールかダイアログを開始してください。",
+  "ui.replace_sketch.from_file": "デザインファイルから…",
+  "ui.replace_sketch.no_sketches": "そのデザインには取り込めるスケッチがありません",
   "ui.replace_with_link_done": "コピーはリンクされたデザインの配置になりました。",
   "ui.report_a_bug": "不具合を報告",
   "ui.report_characters_left_one": "残り {count} 文字",

assets/locales/ko.json

@@ -992,8 +992,11 @@
   "cmd.panel.dismiss": "패널 임시 보기 닫기",
   "cmd.panel.float": "패널 띄우기",
   "cmd.panel.focus": "패널에 초점 맞추기",
+  "cmd.panel.focus.next": "다음 패널에 초점 맞추기",
+  "cmd.panel.focus.previous": "이전 패널에 초점 맞추기",
   "cmd.panel.list": "패널 목록",
   "cmd.panel.move": "패널 이동",
+  "cmd.panel.move.next_zone": "패널을 다음 영역으로 이동",
   "cmd.panel.native_close": "별도 창의 패널 구역 다시 도킹",
   "cmd.panel.open": "패널 열기",
   "cmd.panel.peek": "접힌 패널 임시 보기",
@@ -1001,6 +1004,12 @@
   "cmd.panel.reset_pair": "패널 구분선 초기화",
   "cmd.panel.resize": "패널 구역 크기 조정",
   "cmd.panel.resize_pair": "패널 구분선 이동",
+  "cmd.panel.sash.down": "패널 구분선을 아래로 이동",
+  "cmd.panel.sash.left": "패널 구분선을 왼쪽으로 이동",
+  "cmd.panel.sash.reset": "초점이 있는 패널 구분선 초기화",
+  "cmd.panel.sash.right": "패널 구분선을 오른쪽으로 이동",
+  "cmd.panel.sash.up": "패널 구분선을 위로 이동",
+  "cmd.panel.toggle": "초점이 있는 패널 접기 전환",
   "cmd.parameters_add": "사용자 매개 변수 추가",
   "cmd.parameters_change": "매개 변수 변경",
   "cmd.parameters_comment": "매개 변수에 설명 추가",
@@ -1117,6 +1126,7 @@
   "cmd.sketch.construction_line.tangent_external": "외부 점을 지나는 접선",
   "cmd.sketch.construction_line.tangent_two": "공통 접선",
   "cmd.sketch.construction_line.vertical": "수직 보조 직선",
+  "cmd.sketch.replace": "스케치 바꾸기",
   "cmd.sketch_arc_center_point": "중심점 호",
   "cmd.sketch_arc_tangent": "접선 호",
   "cmd.sketch_arc_three_point": "3점 호",
@@ -1928,6 +1938,8 @@
   "prefs.design_tools.degrees": "도",
   "prefs.design_tools.double_click_help": "연결된 구성요소를 제자리에서 편집할 수도 있습니다.",
   "prefs.design_tools.ghost": "이동한 부품의 이전 위치를 고스트로 표시",
+  "prefs.design_tools.hole_group": "함께 만든 구멍 그룹화",
+  "prefs.design_tools.hole_group_help": "한 번에 만든 구멍은 기록에서 하나의 폴더를 공유하며, 처음에는 닫혀 있습니다. 폴더를 열어 각 구멍을 개별적으로 편집하세요.",
   "prefs.design_tools.hole_moves_help": "면을 다시 선택하면 구멍을 제거하지 않고 이동합니다.",
   "prefs.design_tools.hole_snaps_help": "면의 가운데와 원형 모서리의 중심입니다.",
   "prefs.design_tools.imported_files": "가져온 파일",
@@ -2005,6 +2017,8 @@
   "prefs.history": "이력",
   "prefs.history_bar_groups": "이력 막대를 그룹으로 접기",
   "prefs.history_bar_groups_note": "긴 이력에서는 한 컴포넌트의 연속된 특성을 하나의 칩으로 접고, 특성 폴더는 접힌 상태로 시작합니다. 삽입한 STEP 어셈블리는 Group 폴더에 들어갑니다. 끄면 각 특성을 표시하고, 폴더를 펼친 상태로 시작하며, 폴더를 만들지 않습니다.",
+  "prefs.history_folder_kind_icon": "폴더 아이콘을 안의 피처에서 가져오기",
+  "prefs.history_folder_kind_icon_note": "피처가 모두 같은 종류인 기록 폴더는 그 피처의 아이콘을 표시합니다.",
   "prefs.history_group_joints": "이력에서 조인트 묶기",
   "prefs.history_group_joints_note": "조인트가 두 개 이상이면 개수가 표시된 버튼 하나로 묶고, 클릭하면 각 조인트를 표시합니다. 끄면 각 조인트를 하나씩 표시합니다.",
   "prefs.history_origin_bodies": "원점과 바디를 맨 위에 표시",
@@ -2132,6 +2146,8 @@
   "prefs.select_other_hidden": "다른 항목 선택으로 숨겨진 형상 선택",
   "prefs.select_other_hidden_help": "켜짐: 포인터 근처의 숨겨진 바디, 스케치 및 가려진 모서리를 포함합니다. 꺼짐: 포인터 바로 아래에 보이는 형상만 포함하는 기존 목록을 사용합니다.",
   "prefs.selecting": "선택",
+  "prefs.shared_panel_layout": "공유 패널 레이아웃 사용",
+  "prefs.shared_panel_layout_help": "기존 브라우저, 기록 및 도우미를 이동 가능한 패널로 표시합니다. 환경설정을 적용하면 변경 사항이 반영됩니다.",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift는 추가만, Ctrl / Cmd는 토글",
   "prefs.shift_add_note": "켬: Shift는 추가, Ctrl / Cmd는 토글. 끔(기본값): 둘 다 토글.",
@@ -2653,7 +2669,7 @@
   "render.cpu_opaque_required": "CPU 레이 트레이싱에는 불투명 배경이 필요합니다. 계속하려면 투명 배경을 해제하세요.",
   "render.cpu_options_pending": "이 CPU 패널은 아직 발광, 표면 효과, 유리, 이방성을 편집할 수 없습니다. 사용하기 전에 해당 API 옵션을 해제하세요.",
   "render.cpu_path_depth": "경로 깊이",
-  "render.cpu_path_help": "불투명 표면 사이에서 반사되고 지원되는 유리 형상을 통과하는 빛을 계산합니다. 점진적 렌더링과 레이 추적 그림자가 필요합니다. 경로 깊이는 첫 교점부터 조명이 계산되는 표면, 유리 경계 및 산란 이벤트를 셉니다(1–16). 깊이 1은 불투명 표면의 직접 조명만 계산합니다. 값을 높이면 반사나 유리 통과가 늘어나며 시간이 더 걸릴 수 있습니다. 사용자 반사 설정이나 이방성을 사용하려면 간접 조명을 끄세요.",
+  "render.cpu_path_help": "불투명 표면 사이에서 반사되고 지원되는 유리 형상을 통과하는 빛을 계산합니다. 점진적 렌더링과 레이 추적 그림자가 필요합니다. 경로 깊이는 첫 교점부터 조명이 계산되는 표면, 유리 경계 및 산란 이벤트를 셉니다(1–64). 깊이 1은 불투명 표면의 직접 조명만 계산합니다. 값을 높이면 반사나 유리 통과가 늘어나며 시간이 더 걸릴 수 있습니다. 사용자 반사 설정이나 이방성을 사용하려면 간접 조명을 끄세요.",
   "render.cpu_path_lighting": "간접 조명",
   "render.cpu_path_optics_reason": "설정은 유지됩니다. 사용자 반사 설정이나 이방성을 사용하려면 간접 조명을 끄세요.",
   "render.cpu_point": "점 조명",
@@ -4716,6 +4732,7 @@
   "ui.heading_plastic": "플라스틱",
   "ui.heading_position": "배치",
   "ui.heading_prepare": "준비",
+  "ui.heading_press_pull": "밀기/당기기",
   "ui.heading_rectangular_pattern": "직사각형 패턴",
   "ui.heading_revolve": "회전",
   "ui.heading_right": "우측면",
@@ -5037,6 +5054,8 @@
   "ui.profiles": "프로파일",
   "ui.project": "투영",
   "ui.project_face_edges_sketch": "면 모서리를 새 스케치로 투영",
+  "ui.project_references_construction": "참조를 구성선으로 투영",
+  "ui.project_references_construction_note": "투영, 교차, 3D 형상 포함과 면 위 새 스케치의 면 모서리가 구성선으로 만들어집니다. 프로파일에 포함되지 않는 그리기용 참조이며, 모델과의 연결은 유지됩니다.",
   "ui.properties": "속성",
   "ui.properties.copy_matrix": "행렬 복사",
   "ui.properties.first_moments": "1차 모멘트",
@@ -5078,6 +5097,8 @@
   "ui.renderer": "렌더러",
   "ui.repeat": "반복",
   "ui.repeat_nothing": "아직 반복할 것이 없습니다. 먼저 도구나 대화 상자를 시작하세요.",
+  "ui.replace_sketch.from_file": "디자인 파일에서…",
+  "ui.replace_sketch.no_sketches": "그 디자인에는 가져올 스케치가 없습니다",
   "ui.replace_with_link_done": "복사본이 이제 링크된 디자인의 배치가 되었습니다.",
   "ui.report_a_bug": "버그 신고",
   "ui.reset": "재설정",

assets/locales/pending/opus-quality.json

@@ -0,0 +1,66 @@
+{
+  "ar": {
+    "render.caustics_area_lights": "تأثيرات الضوء المركّز من الأضواء المساحية",
+    "render.caustics_environment": "تأثيرات الضوء المركّز من البيئة",
+    "render.metal_energy_compensation": "استعادة انعكاس المعادن الخشنة",
+    "render.metal_energy_compensation_help": "عوّض الضوء الذي تفقده الأسطح المعدنية الخشنة بين أوجهها المجهرية. يتطلب معالج CPU إضاءة غير مباشرة.",
+    "render.texture_filtering": "ترشيح تفاصيل الخامات",
+    "render.texture_filtering_help": "استخدم مستويات التفاصيل والترشيح المتباين لتقليل تعرّج الخامات عند التصغير. يزيد استهلاك الذاكرة؛ يبقى الوضع القديم معطّلاً."
+  },
+  "de": {
+    "render.caustics_area_lights": "Kaustiken von Flächenlichtern",
+    "render.caustics_environment": "Kaustiken aus der Umgebung",
+    "render.metal_energy_compensation": "Reflexion rauer Metalle wiederherstellen",
+    "render.metal_energy_compensation_help": "Gleicht den Lichtverlust zwischen den Mikrofacetten rauer Metalle aus. Die CPU benötigt indirekte Beleuchtung.",
+    "render.texture_filtering": "Texturdetails filtern",
+    "render.texture_filtering_help": "Mip-Stufen und anisotrope Filterung verringern Flimmern verkleinerter Texturen. Benötigt zusätzlichen Speicher; ausgeschaltet bleibt die bisherige Filterung."
+  },
+  "en": {
+    "render.caustics_area_lights": "Area light caustics",
+    "render.caustics_environment": "Environment caustics",
+    "render.metal_energy_compensation": "Recover rough metal reflectance",
+    "render.metal_energy_compensation_help": "Compensate for light lost between rough metal microfacets. CPU rendering needs Indirect lighting.",
+    "render.texture_filtering": "Filter texture detail",
+    "render.texture_filtering_help": "Use mip levels and anisotropic filtering to reduce texture aliasing under minification. Uses more memory; off retains the previous filtering."
+  },
+  "he": {
+    "render.caustics_area_lights": "קאוסטיקה מתאורת שטח",
+    "render.caustics_environment": "קאוסטיקה מתאורת הסביבה",
+    "render.metal_energy_compensation": "שחזור ההחזר של מתכת מחוספסת",
+    "render.metal_energy_compensation_help": "מפצה על האור שאובד בין הפאות המיקרוסקופיות של מתכת מחוספסת. עיבוד במעבד דורש תאורה עקיפה.",
+    "render.texture_filtering": "סינון פרטי מרקם",
+    "render.texture_filtering_help": "שימוש ברמות פירוט ובסינון אנאיזוטרופי מפחית שינון במרקמים מוקטנים. דורש יותר זיכרון; כשהאפשרות כבויה נשמר הסינון הקודם."
+  },
+  "ja": {
+    "render.caustics_area_lights": "面光源のコースティクス",
+    "render.caustics_environment": "環境光のコースティクス",
+    "render.metal_energy_compensation": "粗い金属の反射を補正",
+    "render.metal_energy_compensation_help": "粗い金属の微小面間で失われる光を補います。CPU レンダリングには間接照明が必要です。",
+    "render.texture_filtering": "テクスチャの細部をフィルタリング",
+    "render.texture_filtering_help": "ミップレベルと異方性フィルタリングで縮小時のちらつきを抑えます。メモリ使用量が増えます。オフでは従来のフィルタリングを維持します。"
+  },
+  "ko": {
+    "render.caustics_area_lights": "면광원 집광 효과",
+    "render.caustics_environment": "환경광 집광 효과",
+    "render.metal_energy_compensation": "거친 금속의 반사 복원",
+    "render.metal_energy_compensation_help": "거친 금속의 미세면 사이에서 손실되는 빛을 보정합니다. CPU 렌더링에는 간접 조명이 필요합니다.",
+    "render.texture_filtering": "텍스처 세부 필터링",
+    "render.texture_filtering_help": "밉 레벨과 비등방성 필터링으로 축소 시 텍스처 계단 현상을 줄입니다. 메모리를 더 사용하며 끄면 기존 필터링을 유지합니다."
+  },
+  "vi": {
+    "render.caustics_area_lights": "Tụ quang từ đèn diện tích",
+    "render.caustics_environment": "Tụ quang từ ánh sáng môi trường",
+    "render.metal_energy_compensation": "Khôi phục phản xạ của kim loại nhám",
+    "render.metal_energy_compensation_help": "Bù ánh sáng thất thoát giữa các vi diện của kim loại nhám. Kết xuất CPU cần chiếu sáng gián tiếp.",
+    "render.texture_filtering": "Lọc chi tiết kết cấu",
+    "render.texture_filtering_help": "Dùng các mức mip và lọc bất đẳng hướng để giảm răng cưa khi thu nhỏ kết cấu. Tốn thêm bộ nhớ; tắt để giữ cách lọc trước đây."
+  },
+  "zh": {
+    "render.caustics_area_lights": "面光源焦散",
+    "render.caustics_environment": "环境光焦散",
+    "render.metal_energy_compensation": "恢复粗糙金属的反射",
+    "render.metal_energy_compensation_help": "补偿粗糙金属微表面之间损失的光能。CPU 渲染需要间接照明。",
+    "render.texture_filtering": "过滤纹理细节",
+    "render.texture_filtering_help": "使用多级纹理和各向异性过滤，减少纹理缩小时的锯齿。需要更多内存；关闭时保留原有过滤方式。"
+  }
+}

assets/locales/pending/opus-render-controls.json

@@ -0,0 +1,386 @@
+{
+  "en": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "Saved value: {samples} spp. New selections are limited to {maximum} spp.",
+    "render.quality_preset_limit": "This preset exceeds the 16384 spp selection limit. Choose a sample count up to 16384.",
+    "render.supersampling": "Supersampling",
+    "render.supersampling_off": "Off",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "Render at twice the width and height, then reduce in linear light. The output size stays unchanged.",
+    "render.supersampling_dimensions": "Renders {width} × {height} and reduces to {output_width} × {output_height}. Uses four times the pixels.",
+    "render.cpu_threads": "CPU workers",
+    "render.cpu_threads_auto": "Auto",
+    "render.cpu_threads_single": "Single",
+    "render.cpu_threads_custom": "Custom",
+    "render.cpu_threads_help": "Auto uses available CPU workers. One worker runs serially. More workers can need more memory.",
+    "render.cpu_threads_web": "Browser rendering uses one cooperative worker. The saved desktop worker choice is preserved.",
+    "render.denoise_passes": "Filter passes",
+    "render.denoise_strength": "Denoising strength",
+    "render.denoise_firefly": "Suppress isolated bright pixels",
+    "render.denoise_settings_help": "More passes smooth a wider area. Strength controls how much filtering each pass applies. Unsupported optical paths remain unfiltered.",
+    "render.denoise_diagnostics_enable": "Collect denoising diagnostics",
+    "render.denoise_diagnostics_help": "Collects eligible and skipped pixel counts even when denoising is off. Counts use the internal render size; the mask uses the output size.",
+    "render.denoise_diagnostics_title": "Denoising diagnostics",
+    "render.denoise_diagnostics_grid": "Pixel counts at internal size {width} × {height}.",
+    "render.denoise_diagnostics_counts": "Eligible: {eligible} · Skipped: {skipped}",
+    "render.denoise_mask_unavailable": "Enable denoising diagnostics and render an image to inspect its mask.",
+    "render.denoise_mask_copy_help": "Export the denoising mask as PNG, or return to the rendered image to copy it.",
+    "render.denoise_view_image": "Rendered image",
+    "render.denoise_view_mask": "Denoising mask",
+    "render.denoise_export_mask": "Export mask PNG",
+    "render.denoise_format_mask": "Mask PNG",
+    "render.denoise_class_unavailable": "Skipped: no guide",
+    "render.denoise_class_surface": "Eligible: surface",
+    "render.denoise_class_optical": "Eligible: refracted surface",
+    "render.denoise_class_background": "Skipped: background",
+    "render.denoise_class_emitter": "Skipped: light emitter",
+    "render.denoise_class_material": "Skipped: unsupported material",
+    "render.denoise_class_nested": "Skipped: nested medium",
+    "render.denoise_class_lens": "Skipped: depth of field",
+    "render.denoise_class_volume": "Skipped: volume scattering",
+    "render.denoise_class_depth": "Skipped: path depth limit",
+    "render.denoise_class_degenerate": "Skipped: degenerate path",
+    "render.denoise_class_exit": "Skipped: incompatible exit",
+    "render.denoise_class_tir": "Skipped: total internal reflection",
+    "render.denoise_class_transmission": "Skipped: further transmission",
+    "render.denoise_class_reflection": "Skipped: reflective endpoint",
+    "render.denoise_class_identity": "Skipped: guide identity limit",
+    "render.denoise_class_coverage": "Skipped: partial coverage"
+  },
+  "ar": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "القيمة المحفوظة: {samples} عينة لكل بكسل. تقتصر الاختيارات الجديدة على {maximum} عينة لكل بكسل.",
+    "render.quality_preset_limit": "يتجاوز هذا الإعداد المسبق حد الاختيار البالغ 16384 عينة لكل بكسل. اختر عدد عينات لا يتجاوز 16384.",
+    "render.supersampling": "أخذ عينات فائقة",
+    "render.supersampling_off": "إيقاف",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "يُصيَّر المشهد بضعف العرض والارتفاع، ثم يُصغَّر في فضاء الإضاءة الخطي. يبقى حجم الإخراج دون تغيير.",
+    "render.supersampling_dimensions": "يُصيَّر بحجم {width} × {height} ويُصغَّر إلى {output_width} × {output_height}. يستخدم أربعة أضعاف عدد البكسلات.",
+    "render.cpu_threads": "خيوط المعالجة",
+    "render.cpu_threads_auto": "تلقائي",
+    "render.cpu_threads_single": "واحد",
+    "render.cpu_threads_custom": "مخصص",
+    "render.cpu_threads_help": "يستخدم الوضع التلقائي خيوط المعالجة المتاحة. ينفّذ خيط واحد العمل تسلسليًا. قد تحتاج الخيوط الإضافية إلى ذاكرة أكبر.",
+    "render.cpu_threads_web": "يستخدم التصيير في المتصفح خيطًا تعاونيًا واحدًا. يُحفظ اختيار خيوط المعالجة الخاص بسطح المكتب.",
+    "render.denoise_passes": "مرات الترشيح",
+    "render.denoise_strength": "قوة إزالة الضوضاء",
+    "render.denoise_firefly": "تقليل البكسلات الساطعة المعزولة",
+    "render.denoise_settings_help": "تُنعّم مرات الترشيح الإضافية مساحة أوسع. تحدد القوة مقدار الترشيح المطبّق في كل مرة. تبقى المسارات البصرية غير المدعومة دون ترشيح.",
+    "render.denoise_diagnostics_enable": "جمع تشخيصات إزالة الضوضاء",
+    "render.denoise_diagnostics_help": "يجمع أعداد البكسلات المؤهلة والمتجاوزة حتى عند إيقاف إزالة الضوضاء. تعتمد الأعداد على حجم التصيير الداخلي، ويعتمد القناع على حجم الإخراج.",
+    "render.denoise_diagnostics_title": "تشخيصات إزالة الضوضاء",
+    "render.denoise_diagnostics_grid": "أعداد البكسلات بالحجم الداخلي {width} × {height}.",
+    "render.denoise_diagnostics_counts": "المؤهلة: {eligible} · المتجاوزة: {skipped}",
+    "render.denoise_mask_unavailable": "فعّل تشخيصات إزالة الضوضاء وصيّر صورة لفحص قناعها.",
+    "render.denoise_mask_copy_help": "صدّر قناع إزالة الضوضاء بصيغة PNG، أو عُد إلى الصورة المصيّرة لنسخها.",
+    "render.denoise_view_image": "الصورة المصيّرة",
+    "render.denoise_view_mask": "قناع إزالة الضوضاء",
+    "render.denoise_export_mask": "تصدير القناع بصيغة PNG",
+    "render.denoise_format_mask": "قناع PNG",
+    "render.denoise_class_unavailable": "متجاوز: بلا دليل",
+    "render.denoise_class_surface": "مؤهل: سطح",
+    "render.denoise_class_optical": "مؤهل: سطح عبر انكسار",
+    "render.denoise_class_background": "متجاوز: خلفية",
+    "render.denoise_class_emitter": "متجاوز: مصدر ضوء",
+    "render.denoise_class_material": "متجاوز: مادة غير مدعومة",
+    "render.denoise_class_nested": "متجاوز: وسط متداخل",
+    "render.denoise_class_lens": "متجاوز: عمق المجال",
+    "render.denoise_class_volume": "متجاوز: تشتت حجمي",
+    "render.denoise_class_depth": "متجاوز: حد عمق المسار",
+    "render.denoise_class_degenerate": "متجاوز: مسار متدهور",
+    "render.denoise_class_exit": "متجاوز: خروج غير متوافق",
+    "render.denoise_class_tir": "متجاوز: انعكاس داخلي كلي",
+    "render.denoise_class_transmission": "متجاوز: نفاذ إضافي",
+    "render.denoise_class_reflection": "متجاوز: نهاية عاكسة",
+    "render.denoise_class_identity": "متجاوز: حد هوية الدليل",
+    "render.denoise_class_coverage": "متجاوز: تغطية جزئية"
+  },
+  "he": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "ערך שמור: {samples} דגימות לפיקסל. בחירות חדשות מוגבלות ל־{maximum} דגימות לפיקסל.",
+    "render.quality_preset_limit": "הגדרה קבועה זו חורגת ממגבלת הבחירה של 16384 דגימות לפיקסל. יש לבחור עד 16384 דגימות.",
+    "render.supersampling": "דגימת יתר",
+    "render.supersampling_off": "כבוי",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "רינדור ברוחב ובגובה כפולים, ואז הקטנה במרחב אור ליניארי. גודל הפלט נשאר ללא שינוי.",
+    "render.supersampling_dimensions": "רינדור בגודל {width} × {height} והקטנה ל־{output_width} × {output_height}. נעשה שימוש בפי ארבעה פיקסלים.",
+    "render.cpu_threads": "תהליכוני CPU",
+    "render.cpu_threads_auto": "אוטומטי",
+    "render.cpu_threads_single": "יחיד",
+    "render.cpu_threads_custom": "מותאם",
+    "render.cpu_threads_help": "המצב האוטומטי משתמש בתהליכוני ה־CPU הזמינים. תהליכון יחיד פועל באופן סדרתי. תהליכונים נוספים עשויים לדרוש יותר זיכרון.",
+    "render.cpu_threads_web": "רינדור בדפדפן משתמש בתהליכון שיתופי אחד. בחירת התהליכונים השמורה למחשב נשמרת.",
+    "render.denoise_passes": "מעברי סינון",
+    "render.denoise_strength": "עוצמת הפחתת רעש",
+    "render.denoise_firefly": "דיכוי פיקסלים בהירים מבודדים",
+    "render.denoise_settings_help": "מעברים נוספים מחליקים אזור רחב יותר. העוצמה קובעת כמה סינון מופעל בכל מעבר. מסלולים אופטיים שאינם נתמכים נשארים ללא סינון.",
+    "render.denoise_diagnostics_enable": "איסוף נתוני אבחון להפחתת רעש",
+    "render.denoise_diagnostics_help": "נאספים מספרי הפיקסלים המתאימים ואלה שדולגו, גם כשהפחתת הרעש כבויה. הספירה לפי גודל הרינדור הפנימי; המסכה לפי גודל הפלט.",
+    "render.denoise_diagnostics_title": "אבחון הפחתת רעש",
+    "render.denoise_diagnostics_grid": "ספירת פיקסלים בגודל הפנימי {width} × {height}.",
+    "render.denoise_diagnostics_counts": "מתאימים: {eligible} · דולגו: {skipped}",
+    "render.denoise_mask_unavailable": "יש להפעיל אבחון הפחתת רעש ולרנדר תמונה כדי לבדוק את המסכה שלה.",
+    "render.denoise_mask_copy_help": "אפשר לייצא את מסכת הפחתת הרעש כ־PNG, או לחזור לתמונה המרונדרת כדי להעתיק אותה.",
+    "render.denoise_view_image": "תמונה מרונדרת",
+    "render.denoise_view_mask": "מסכת הפחתת רעש",
+    "render.denoise_export_mask": "ייצוא המסכה כ־PNG",
+    "render.denoise_format_mask": "מסכה PNG",
+    "render.denoise_class_unavailable": "דולג: אין נתוני הנחיה",
+    "render.denoise_class_surface": "מתאים: משטח",
+    "render.denoise_class_optical": "מתאים: משטח דרך שבירה",
+    "render.denoise_class_background": "דולג: רקע",
+    "render.denoise_class_emitter": "דולג: מקור אור",
+    "render.denoise_class_material": "דולג: חומר לא נתמך",
+    "render.denoise_class_nested": "דולג: תווך מקונן",
+    "render.denoise_class_lens": "דולג: עומק שדה",
+    "render.denoise_class_volume": "דולג: פיזור נפחי",
+    "render.denoise_class_depth": "דולג: מגבלת עומק מסלול",
+    "render.denoise_class_degenerate": "דולג: מסלול מנוון",
+    "render.denoise_class_exit": "דולג: יציאה לא תואמת",
+    "render.denoise_class_tir": "דולג: החזרה פנימית מלאה",
+    "render.denoise_class_transmission": "דולג: העברה נוספת",
+    "render.denoise_class_reflection": "דולג: נקודת סיום מחזירה",
+    "render.denoise_class_identity": "דולג: מגבלת מזהי הנחיה",
+    "render.denoise_class_coverage": "דולג: כיסוי חלקי"
+  },
+  "ja": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "保存値: {samples} spp。新しい選択値の上限は {maximum} spp です。",
+    "render.quality_preset_limit": "このプリセットは選択上限の 16384 spp を超えています。16384 以下のサンプル数を選択してください。",
+    "render.supersampling": "スーパーサンプリング",
+    "render.supersampling_off": "オフ",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "幅と高さをそれぞれ 2 倍にしてレンダリングし、リニアライトで縮小します。出力サイズは変わりません。",
+    "render.supersampling_dimensions": "{width} × {height} でレンダリングし、{output_width} × {output_height} に縮小します。ピクセル数は 4 倍になります。",
+    "render.cpu_threads": "CPU ワーカー",
+    "render.cpu_threads_auto": "自動",
+    "render.cpu_threads_single": "1 ワーカー",
+    "render.cpu_threads_custom": "カスタム",
+    "render.cpu_threads_help": "自動では利用可能な CPU ワーカーを使用します。1 ワーカーでは順次実行します。ワーカー数を増やすとメモリ使用量が増える場合があります。",
+    "render.cpu_threads_web": "ブラウザーでのレンダリングは単一の協調ワーカーを使用します。保存されたデスクトップ用ワーカー設定は保持されます。",
+    "render.denoise_passes": "フィルターパス数",
+    "render.denoise_strength": "ノイズ除去の強度",
+    "render.denoise_firefly": "孤立した高輝度ピクセルを抑制",
+    "render.denoise_settings_help": "パス数を増やすと、より広い範囲が平滑化されます。強度は各パスでのフィルター適用量を調整します。未対応の光路にはフィルターを適用しません。",
+    "render.denoise_diagnostics_enable": "ノイズ除去の診断情報を収集",
+    "render.denoise_diagnostics_help": "ノイズ除去がオフでも、対象と対象外のピクセル数を収集します。集計は内部レンダリングサイズ、マスクは出力サイズに対応します。",
+    "render.denoise_diagnostics_title": "ノイズ除去の診断",
+    "render.denoise_diagnostics_grid": "内部サイズ {width} × {height} でのピクセル数。",
+    "render.denoise_diagnostics_counts": "対象: {eligible} · 対象外: {skipped}",
+    "render.denoise_mask_unavailable": "ノイズ除去の診断を有効にして画像をレンダリングすると、マスクを確認できます。",
+    "render.denoise_mask_copy_help": "ノイズ除去マスクを PNG で書き出すか、レンダリング画像に戻ってコピーしてください。",
+    "render.denoise_view_image": "レンダリング画像",
+    "render.denoise_view_mask": "ノイズ除去マスク",
+    "render.denoise_export_mask": "マスク PNG を書き出す",
+    "render.denoise_format_mask": "マスク PNG",
+    "render.denoise_class_unavailable": "対象外: ガイドなし",
+    "render.denoise_class_surface": "対象: サーフェス",
+    "render.denoise_class_optical": "対象: 屈折越しのサーフェス",
+    "render.denoise_class_background": "対象外: 背景",
+    "render.denoise_class_emitter": "対象外: 発光体",
+    "render.denoise_class_material": "対象外: 未対応のマテリアル",
+    "render.denoise_class_nested": "対象外: 入れ子の媒質",
+    "render.denoise_class_lens": "対象外: 被写界深度",
+    "render.denoise_class_volume": "対象外: ボリューム散乱",
+    "render.denoise_class_depth": "対象外: 経路深度の上限",
+    "render.denoise_class_degenerate": "対象外: 退化した経路",
+    "render.denoise_class_exit": "対象外: 不整合な出射",
+    "render.denoise_class_tir": "対象外: 全反射",
+    "render.denoise_class_transmission": "対象外: 追加の透過",
+    "render.denoise_class_reflection": "対象外: 反射する終点",
+    "render.denoise_class_identity": "対象外: ガイド識別子の上限",
+    "render.denoise_class_coverage": "対象外: 部分的なカバレッジ"
+  },
+  "vi": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "Giá trị đã lưu: {samples} mẫu/pixel. Lựa chọn mới được giới hạn ở {maximum} mẫu/pixel.",
+    "render.quality_preset_limit": "Thiết lập sẵn này vượt quá giới hạn 16384 mẫu/pixel. Hãy chọn số mẫu tối đa là 16384.",
+    "render.supersampling": "Lấy mẫu siêu phân giải",
+    "render.supersampling_off": "Tắt",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "Kết xuất với chiều rộng và chiều cao gấp đôi, rồi thu nhỏ trong không gian ánh sáng tuyến tính. Kích thước đầu ra không đổi.",
+    "render.supersampling_dimensions": "Kết xuất ở {width} × {height} rồi thu nhỏ về {output_width} × {output_height}. Sử dụng số pixel gấp bốn lần.",
+    "render.cpu_threads": "Luồng CPU",
+    "render.cpu_threads_auto": "Tự động",
+    "render.cpu_threads_single": "Một luồng",
+    "render.cpu_threads_custom": "Tùy chỉnh",
+    "render.cpu_threads_help": "Chế độ tự động dùng các luồng CPU khả dụng. Một luồng chạy tuần tự. Nhiều luồng hơn có thể cần nhiều bộ nhớ hơn.",
+    "render.cpu_threads_web": "Kết xuất trong trình duyệt dùng một luồng phối hợp. Lựa chọn luồng đã lưu cho ứng dụng máy tính được giữ nguyên.",
+    "render.denoise_passes": "Số lượt lọc",
+    "render.denoise_strength": "Cường độ khử nhiễu",
+    "render.denoise_firefly": "Giảm các pixel sáng đơn lẻ",
+    "render.denoise_settings_help": "Nhiều lượt lọc hơn làm mịn vùng rộng hơn. Cường độ điều chỉnh mức lọc áp dụng trong mỗi lượt. Các đường truyền quang học không được hỗ trợ vẫn không được lọc.",
+    "render.denoise_diagnostics_enable": "Thu thập chẩn đoán khử nhiễu",
+    "render.denoise_diagnostics_help": "Thu thập số pixel đủ điều kiện và bị bỏ qua ngay cả khi tắt khử nhiễu. Số lượng dựa trên kích thước kết xuất nội bộ; mặt nạ dùng kích thước đầu ra.",
+    "render.denoise_diagnostics_title": "Chẩn đoán khử nhiễu",
+    "render.denoise_diagnostics_grid": "Số pixel ở kích thước nội bộ {width} × {height}.",
+    "render.denoise_diagnostics_counts": "Đủ điều kiện: {eligible} · Bỏ qua: {skipped}",
+    "render.denoise_mask_unavailable": "Bật chẩn đoán khử nhiễu và kết xuất ảnh để kiểm tra mặt nạ.",
+    "render.denoise_mask_copy_help": "Xuất mặt nạ khử nhiễu dưới dạng PNG, hoặc quay lại ảnh đã kết xuất để sao chép.",
+    "render.denoise_view_image": "Ảnh đã kết xuất",
+    "render.denoise_view_mask": "Mặt nạ khử nhiễu",
+    "render.denoise_export_mask": "Xuất mặt nạ PNG",
+    "render.denoise_format_mask": "PNG mặt nạ",
+    "render.denoise_class_unavailable": "Bỏ qua: không có dữ liệu hướng dẫn",
+    "render.denoise_class_surface": "Đủ điều kiện: bề mặt",
+    "render.denoise_class_optical": "Đủ điều kiện: bề mặt qua khúc xạ",
+    "render.denoise_class_background": "Bỏ qua: nền",
+    "render.denoise_class_emitter": "Bỏ qua: nguồn phát sáng",
+    "render.denoise_class_material": "Bỏ qua: vật liệu không hỗ trợ",
+    "render.denoise_class_nested": "Bỏ qua: môi trường lồng nhau",
+    "render.denoise_class_lens": "Bỏ qua: độ sâu trường ảnh",
+    "render.denoise_class_volume": "Bỏ qua: tán xạ thể tích",
+    "render.denoise_class_depth": "Bỏ qua: giới hạn độ sâu đường truyền",
+    "render.denoise_class_degenerate": "Bỏ qua: đường truyền suy biến",
+    "render.denoise_class_exit": "Bỏ qua: điểm thoát không tương thích",
+    "render.denoise_class_tir": "Bỏ qua: phản xạ toàn phần",
+    "render.denoise_class_transmission": "Bỏ qua: truyền qua tiếp",
+    "render.denoise_class_reflection": "Bỏ qua: điểm cuối phản xạ",
+    "render.denoise_class_identity": "Bỏ qua: giới hạn định danh hướng dẫn",
+    "render.denoise_class_coverage": "Bỏ qua: độ phủ một phần"
+  },
+  "zh": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "已保存的值：{samples} spp。新选择的上限为 {maximum} spp。",
+    "render.quality_preset_limit": "此预设超过 16384 spp 的选择上限。请选择不超过 16384 的采样数。",
+    "render.supersampling": "超采样",
+    "render.supersampling_off": "关闭",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "以双倍宽度和高度渲染，然后在线性光空间中缩小。输出尺寸保持不变。",
+    "render.supersampling_dimensions": "以 {width} × {height} 渲染，再缩小至 {output_width} × {output_height}。使用四倍像素。",
+    "render.cpu_threads": "CPU 工作线程",
+    "render.cpu_threads_auto": "自动",
+    "render.cpu_threads_single": "单线程",
+    "render.cpu_threads_custom": "自定义",
+    "render.cpu_threads_help": "自动模式使用可用的 CPU 工作线程。单线程按顺序执行。更多线程可能需要更多内存。",
+    "render.cpu_threads_web": "浏览器渲染使用一个协作式工作线程。已保存的桌面线程选择会保留。",
+    "render.denoise_passes": "滤波轮数",
+    "render.denoise_strength": "降噪强度",
+    "render.denoise_firefly": "抑制孤立亮点",
+    "render.denoise_settings_help": "更多轮次会平滑更大范围。强度控制每轮滤波的应用程度。不支持的光路保持未滤波状态。",
+    "render.denoise_diagnostics_enable": "收集降噪诊断信息",
+    "render.denoise_diagnostics_help": "即使关闭降噪，也会收集可滤波和跳过的像素数量。计数基于内部渲染尺寸；蒙版使用输出尺寸。",
+    "render.denoise_diagnostics_title": "降噪诊断",
+    "render.denoise_diagnostics_grid": "内部尺寸 {width} × {height} 下的像素计数。",
+    "render.denoise_diagnostics_counts": "可滤波：{eligible} · 已跳过：{skipped}",
+    "render.denoise_mask_unavailable": "启用降噪诊断并渲染图像后，即可查看其蒙版。",
+    "render.denoise_mask_copy_help": "将降噪蒙版导出为 PNG，或返回渲染图像后复制图像。",
+    "render.denoise_view_image": "渲染图像",
+    "render.denoise_view_mask": "降噪蒙版",
+    "render.denoise_export_mask": "导出蒙版 PNG",
+    "render.denoise_format_mask": "蒙版 PNG",
+    "render.denoise_class_unavailable": "已跳过：无引导数据",
+    "render.denoise_class_surface": "可滤波：表面",
+    "render.denoise_class_optical": "可滤波：折射后的表面",
+    "render.denoise_class_background": "已跳过：背景",
+    "render.denoise_class_emitter": "已跳过：发光体",
+    "render.denoise_class_material": "已跳过：不支持的材质",
+    "render.denoise_class_nested": "已跳过：嵌套介质",
+    "render.denoise_class_lens": "已跳过：景深",
+    "render.denoise_class_volume": "已跳过：体积散射",
+    "render.denoise_class_depth": "已跳过：路径深度上限",
+    "render.denoise_class_degenerate": "已跳过：退化路径",
+    "render.denoise_class_exit": "已跳过：不兼容的出射",
+    "render.denoise_class_tir": "已跳过：全内反射",
+    "render.denoise_class_transmission": "已跳过：进一步透射",
+    "render.denoise_class_reflection": "已跳过：反射终点",
+    "render.denoise_class_identity": "已跳过：引导标识上限",
+    "render.denoise_class_coverage": "已跳过：部分覆盖"
+  },
+  "de": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "Gespeicherter Wert: {samples} spp. Neue Werte sind auf {maximum} spp begrenzt.",
+    "render.quality_preset_limit": "Diese Vorgabe überschreitet die Auswahlgrenze von 16384 spp. Wählen Sie höchstens 16384 Samples.",
+    "render.supersampling": "Supersampling",
+    "render.supersampling_off": "Aus",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "Mit doppelter Breite und Höhe rendern und anschließend im linearen Farbraum verkleinern. Die Ausgabegröße bleibt unverändert.",
+    "render.supersampling_dimensions": "Rendert {width} × {height} und verkleinert auf {output_width} × {output_height}. Verwendet die vierfache Pixelzahl.",
+    "render.cpu_threads": "CPU-Threads",
+    "render.cpu_threads_auto": "Auto",
+    "render.cpu_threads_single": "Einzeln",
+    "render.cpu_threads_custom": "Eigene",
+    "render.cpu_threads_help": "Auto verwendet die verfügbaren CPU-Threads. Ein Thread arbeitet seriell. Mehr Threads können mehr Speicher benötigen.",
+    "render.cpu_threads_web": "Im Browser wird ein kooperativer Thread verwendet. Die gespeicherte Desktop-Auswahl bleibt erhalten.",
+    "render.denoise_passes": "Filterdurchläufe",
+    "render.denoise_strength": "Entrauschungsstärke",
+    "render.denoise_firefly": "Einzelne helle Pixel unterdrücken",
+    "render.denoise_settings_help": "Mehr Durchläufe glätten einen größeren Bereich. Die Stärke regelt die Filterwirkung jedes Durchlaufs. Nicht unterstützte Lichtwege bleiben ungefiltert.",
+    "render.denoise_diagnostics_enable": "Entrauschungsdiagnose erfassen",
+    "render.denoise_diagnostics_help": "Erfasst geeignete und übersprungene Pixel auch ohne Entrauschung. Die Zählung nutzt die interne Rendergröße, die Maske die Ausgabegröße.",
+    "render.denoise_diagnostics_title": "Entrauschungsdiagnose",
+    "render.denoise_diagnostics_grid": "Pixelzahlen bei interner Größe {width} × {height}.",
+    "render.denoise_diagnostics_counts": "Geeignet: {eligible} · Übersprungen: {skipped}",
+    "render.denoise_mask_unavailable": "Aktivieren Sie die Entrauschungsdiagnose und rendern Sie ein Bild, um seine Maske zu prüfen.",
+    "render.denoise_mask_copy_help": "Exportieren Sie die Entrauschungsmaske als PNG oder kehren Sie zum gerenderten Bild zurück, um es zu kopieren.",
+    "render.denoise_view_image": "Gerendertes Bild",
+    "render.denoise_view_mask": "Entrauschungsmaske",
+    "render.denoise_export_mask": "Maske als PNG exportieren",
+    "render.denoise_format_mask": "Maske PNG",
+    "render.denoise_class_unavailable": "Übersprungen: keine Führungsdaten",
+    "render.denoise_class_surface": "Geeignet: Oberfläche",
+    "render.denoise_class_optical": "Geeignet: Oberfläche durch Brechung",
+    "render.denoise_class_background": "Übersprungen: Hintergrund",
+    "render.denoise_class_emitter": "Übersprungen: Lichtquelle",
+    "render.denoise_class_material": "Übersprungen: nicht unterstütztes Material",
+    "render.denoise_class_nested": "Übersprungen: verschachteltes Medium",
+    "render.denoise_class_lens": "Übersprungen: Schärfentiefe",
+    "render.denoise_class_volume": "Übersprungen: Volumenstreuung",
+    "render.denoise_class_depth": "Übersprungen: Pfadtiefengrenze",
+    "render.denoise_class_degenerate": "Übersprungen: entarteter Pfad",
+    "render.denoise_class_exit": "Übersprungen: unpassender Austritt",
+    "render.denoise_class_tir": "Übersprungen: Totalreflexion",
+    "render.denoise_class_transmission": "Übersprungen: weitere Transmission",
+    "render.denoise_class_reflection": "Übersprungen: reflektierender Endpunkt",
+    "render.denoise_class_identity": "Übersprungen: Grenze der Führungskennungen",
+    "render.denoise_class_coverage": "Übersprungen: teilweise Abdeckung"
+  },
+  "ko": {
+    "render.size_8k_uhd": "8K UHD",
+    "render.quality_legacy_samples": "저장된 값: {samples} spp. 새 선택값은 {maximum} spp로 제한됩니다.",
+    "render.quality_preset_limit": "이 프리셋은 선택 한도인 16384 spp를 초과합니다. 샘플 수를 16384 이하로 선택하세요.",
+    "render.supersampling": "슈퍼샘플링",
+    "render.supersampling_off": "끄기",
+    "render.supersampling_x2": "2×",
+    "render.supersampling_help": "가로와 세로를 각각 두 배로 렌더링한 뒤 선형 광 공간에서 축소합니다. 출력 크기는 그대로 유지됩니다.",
+    "render.supersampling_dimensions": "{width} × {height}로 렌더링한 뒤 {output_width} × {output_height}로 축소합니다. 픽셀 수가 네 배가 됩니다.",
+    "render.cpu_threads": "CPU 작업 스레드",
+    "render.cpu_threads_auto": "자동",
+    "render.cpu_threads_single": "단일",
+    "render.cpu_threads_custom": "사용자 지정",
+    "render.cpu_threads_help": "자동은 사용 가능한 CPU 작업 스레드를 사용합니다. 단일 스레드는 순차적으로 실행됩니다. 스레드가 많을수록 메모리가 더 필요할 수 있습니다.",
+    "render.cpu_threads_web": "브라우저 렌더링은 하나의 협력형 작업 스레드를 사용합니다. 저장된 데스크톱 스레드 설정은 유지됩니다.",
+    "render.denoise_passes": "필터 반복 횟수",
+    "render.denoise_strength": "노이즈 제거 강도",
+    "render.denoise_firefly": "고립된 밝은 픽셀 억제",
+    "render.denoise_settings_help": "반복 횟수가 많을수록 더 넓은 영역을 부드럽게 합니다. 강도는 각 단계에서 적용하는 필터의 정도를 조절합니다. 지원되지 않는 광 경로에는 필터를 적용하지 않습니다.",
+    "render.denoise_diagnostics_enable": "노이즈 제거 진단 수집",
+    "render.denoise_diagnostics_help": "노이즈 제거가 꺼져 있어도 적용 가능 픽셀과 건너뛴 픽셀 수를 수집합니다. 집계는 내부 렌더링 크기 기준이며 마스크는 출력 크기를 사용합니다.",
+    "render.denoise_diagnostics_title": "노이즈 제거 진단",
+    "render.denoise_diagnostics_grid": "내부 크기 {width} × {height} 기준 픽셀 수입니다.",
+    "render.denoise_diagnostics_counts": "적용 가능: {eligible} · 건너뜀: {skipped}",
+    "render.denoise_mask_unavailable": "노이즈 제거 진단을 켜고 이미지를 렌더링하면 마스크를 확인할 수 있습니다.",
+    "render.denoise_mask_copy_help": "노이즈 제거 마스크를 PNG로 내보내거나 렌더링 이미지로 돌아가 이미지를 복사하세요.",
+    "render.denoise_view_image": "렌더링 이미지",
+    "render.denoise_view_mask": "노이즈 제거 마스크",
+    "render.denoise_export_mask": "마스크 PNG 내보내기",
+    "render.denoise_format_mask": "마스크 PNG",
+    "render.denoise_class_unavailable": "건너뜀: 가이드 없음",
+    "render.denoise_class_surface": "적용 가능: 표면",
+    "render.denoise_class_optical": "적용 가능: 굴절을 통해 보이는 표면",
+    "render.denoise_class_background": "건너뜀: 배경",
+    "render.denoise_class_emitter": "건너뜀: 발광체",
+    "render.denoise_class_material": "건너뜀: 지원되지 않는 재질",
+    "render.denoise_class_nested": "건너뜀: 중첩된 매질",
+    "render.denoise_class_lens": "건너뜀: 피사계 심도",
+    "render.denoise_class_volume": "건너뜀: 볼륨 산란",
+    "render.denoise_class_depth": "건너뜀: 경로 깊이 한도",
+    "render.denoise_class_degenerate": "건너뜀: 퇴화 경로",
+    "render.denoise_class_exit": "건너뜀: 호환되지 않는 출사",
+    "render.denoise_class_tir": "건너뜀: 전반사",
+    "render.denoise_class_transmission": "건너뜀: 추가 투과",
+    "render.denoise_class_reflection": "건너뜀: 반사 종점",
+    "render.denoise_class_identity": "건너뜀: 가이드 식별자 한도",
+    "render.denoise_class_coverage": "건너뜀: 부분 커버리지"
+  }
+}

assets/locales/vi.json

@@ -265,6 +265,7 @@
   "Edge": "Cạnh",
   "Edges": "Các cạnh",
   "Edit": "Sửa",
+  "Edit Holes": "Sửa các lỗ",
   "Edit Profile Sketch": "Chỉnh sửa phác thảo biên dạng",
   "Edit shortcuts": "Sửa phím tắt",
   "Enable rule": "Bật quy tắc",
@@ -1206,6 +1207,7 @@
   "cmd.material_properties_directional": "Mô đun đàn hồi theo hướng",
   "cmd.material_properties_validate": "Xác thực dữ liệu thuộc tính vật liệu",
   "cmd.mesh_convert": "Chuyển đổi lưới",
+  "cmd.model_body_features": "Liệt kê tính năng của thân",
   "cmd.model_edges": "Danh sách các cạnh",
   "cmd.model_faces": "Danh sách các bề mặt",
   "cmd.model_threads": "Danh sách các đoạn ren",
@@ -1234,8 +1236,11 @@
   "cmd.panel.dismiss": "Đóng chế độ xem tạm của bảng",
   "cmd.panel.float": "Thả nổi bảng",
   "cmd.panel.focus": "Đặt tiêu điểm vào bảng",
+  "cmd.panel.focus.next": "Đặt tiêu điểm vào bảng tiếp theo",
+  "cmd.panel.focus.previous": "Đặt tiêu điểm vào bảng trước",
   "cmd.panel.list": "Liệt kê các bảng",
   "cmd.panel.move": "Di chuyển bảng",
+  "cmd.panel.move.next_zone": "Di chuyển bảng đến vùng tiếp theo",
   "cmd.panel.native_close": "Gắn lại vùng bảng từ cửa sổ riêng",
   "cmd.panel.open": "Mở bảng",
   "cmd.panel.peek": "Xem tạm bảng đã thu gọn",
@@ -1243,6 +1248,12 @@
   "cmd.panel.reset_pair": "Đặt lại thanh chia bảng",
   "cmd.panel.resize": "Đổi kích thước vùng bảng",
   "cmd.panel.resize_pair": "Di chuyển thanh chia bảng",
+  "cmd.panel.sash.down": "Di chuyển thanh chia bảng xuống",
+  "cmd.panel.sash.left": "Di chuyển thanh chia bảng sang trái",
+  "cmd.panel.sash.reset": "Đặt lại thanh chia bảng đang có tiêu điểm",
+  "cmd.panel.sash.right": "Di chuyển thanh chia bảng sang phải",
+  "cmd.panel.sash.up": "Di chuyển thanh chia bảng lên",
+  "cmd.panel.toggle": "Bật/tắt thu gọn bảng đang có tiêu điểm",
   "cmd.parameters_add": "Thêm tham số người dùng",
   "cmd.parameters_change": "Thay đổi tham số",
   "cmd.parameters_comment": "Thêm chú thích tham số",
@@ -1366,6 +1377,7 @@
   "cmd.sketch.construction_line.tangent_external": "Tiếp tuyến qua điểm ngoài",
   "cmd.sketch.construction_line.tangent_two": "Tiếp tuyến chung",
   "cmd.sketch.construction_line.vertical": "Đường dựng hình thẳng đứng",
+  "cmd.sketch.replace": "Thay thế phác thảo",
   "cmd.sketch_arc3d": "Cung tròn 3D",
   "cmd.sketch_arc_center_point": "Cung tròn xác định bởi tâm và điểm",
   "cmd.sketch_arc_tangent": "Cung tròn tiếp tuyến",
@@ -2016,6 +2028,7 @@
   "help.view.visual_style": "Đổi cách vẽ mô hình: tô bóng có hoặc không có cạnh, khung dây, hoặc hiện cạnh khuất. Dùng khung dây để nhìn vào bên trong, tô bóng để có hình ảnh gọn gàng.",
   "history.sketch_under_constrained": "Thiếu ràng buộc ({count} bậc tự do)",
   "history.sketch_under_constrained_one": "Thiếu ràng buộc ({count} bậc tự do)",
+  "hole_folder.applies_to": "Thay đổi áp dụng cho {count} lỗ trong {folder}; mỗi lỗ giữ nguyên vị trí.",
   "hole_presets.confirm_delete": "Xác nhận xóa",
   "hole_presets.delete": "Xóa",
   "hole_presets.delete_prompt": "Xóa mẫu thiết lập sẵn cá nhân này? Các lỗ ren/khoan hiện có sẽ không thay đổi.",
@@ -2515,6 +2528,8 @@
   "prefs.bottom_centre": "Giữa phía dưới",
   "prefs.bottom_right": "Góc dưới bên phải",
   "prefs.browser": "Cây thư mục",
+  "prefs.browser_body_features": "Tính năng dưới thân",
+  "prefs.browser_body_features_note": "Mỗi thân trong trình duyệt có thể mở ra để hiện các tính năng trên dòng thời gian đã tạo nên nó, theo thứ tự dòng thời gian.",
   "prefs.browser_components_open": "Thành phần mở sẵn",
   "prefs.browser_components_open_note": "Mọi thành phần trong trình duyệt đều mở sẵn như trước, thay vì đóng cho đến khi bạn mở.",
   "prefs.browser_eye_left": "Biểu tượng mắt cạnh mũi tên thu gọn",
@@ -2555,7 +2570,11 @@
   "prefs.design_tools.degrees": "Độ",
   "prefs.design_tools.double_click_help": "Hoặc để chỉnh sửa thành phần được liên kết tại chỗ.",
   "prefs.design_tools.ghost": "Hiện vị trí cũ của chi tiết đã di chuyển dưới dạng bóng mờ",
+  "prefs.design_tools.hole_group": "Nhóm các lỗ được tạo cùng lúc",
+  "prefs.design_tools.hole_group_help": "Các lỗ được tạo trong một lần dùng chung một thư mục trong Lịch sử, ban đầu được đóng; mở thư mục để sửa từng lỗ.",
   "prefs.design_tools.hole_moves_help": "Chọn lại mặt sẽ di chuyển lỗ thay vì xóa lỗ.",
+  "prefs.design_tools.hole_several": "Nhiều lỗ trên một mặt",
+  "prefs.design_tools.hole_several_help": "Chọn chỗ khác trên mặt sẽ thêm một lỗ; chọn một lỗ sẽ xóa lỗ đó.",
   "prefs.design_tools.hole_snaps_help": "Điểm giữa của mặt và tâm các cạnh tròn của mặt đó.",
   "prefs.design_tools.imported_files": "Tệp đã nhập",
   "prefs.design_tools.note": "Thông báo",
@@ -2637,6 +2656,8 @@
   "prefs.history": "Lịch sử",
   "prefs.history_bar_groups": "Thu gọn thanh Lịch sử thành nhóm",
   "prefs.history_bar_groups_note": "Trong lịch sử dài, một chuỗi tính năng của cùng một thành phần được thu gọn thành một thẻ, và thư mục tính năng bắt đầu ở dạng thu gọn. Cụm lắp ráp STEP được chèn vào sẽ nằm trong thư mục Group. Khi tắt, mỗi tính năng đều hiện, thư mục bắt đầu ở dạng mở và không tạo thư mục nào.",
+  "prefs.history_folder_kind_icon": "Biểu tượng thư mục theo các tính năng bên trong",
+  "prefs.history_folder_kind_icon_note": "Thư mục Lịch sử có các tính năng cùng một loại sẽ hiện biểu tượng của chúng.",
   "prefs.history_group_joints": "Nhóm các khớp nối trong Lịch sử",
   "prefs.history_group_joints_note": "Từ hai khớp nối trở lên hiện thành một nút kèm số lượng, nhấp vào để hiện từng khớp nối. Khi tắt, mỗi khớp nối hiện riêng.",
   "prefs.history_origin_bodies": "Hiển thị gốc tọa độ và thân khối ở trên cùng",
@@ -2830,6 +2851,8 @@
   "prefs.select_other_hidden": "Chọn hình học ẩn bằng Chọn đối tượng khác",
   "prefs.select_other_hidden_help": "Bật: bao gồm các khối, bản phác thảo ẩn và cạnh bị che gần con trỏ. Tắt: dùng danh sách ban đầu chỉ gồm hình học đang hiển thị ngay dưới con trỏ.",
   "prefs.selecting": "Đang chọn",
+  "prefs.shared_panel_layout": "Dùng bố cục bảng dùng chung",
+  "prefs.shared_panel_layout_help": "Hiển thị Trình duyệt, Lịch sử và Trợ lý hiện có trong các bảng có thể di chuyển. Thay đổi có hiệu lực khi áp dụng tùy chọn.",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift chỉ thêm; Ctrl / Cmd đảo trạng thái chọn",
   "prefs.shift_add_note": "Bật: Shift để thêm vào vùng chọn, Ctrl / Cmd để đảo chọn. Tắt (mặc định): cả hai đều đảo trạng thái chọn.",
@@ -3374,7 +3397,7 @@
   "render.cpu_opaque_required": "Dò tia trên CPU yêu cầu nền đục. Hãy bỏ chọn 'Nền trong suốt' để tiếp tục.",
   "render.cpu_options_pending": "Bảng điều khiển CPU này chưa hỗ trợ chỉnh sửa tự phát xạ, hiệu ứng bề mặt, thủy tinh hoặc bất đẳng hướng. Hãy xóa các tùy chọn API đó trước khi sử dụng.",
   "render.cpu_path_depth": "Độ sâu đường truyền",
-  "render.cpu_path_help": "Tính ánh sáng phản xạ giữa các bề mặt đục và truyền qua các hình kính được hỗ trợ. Cần kết xuất lũy tiến và bóng dò tia. Độ sâu đường đi đếm các bề mặt được chiếu sáng, ranh giới kính và các sự kiện tán xạ từ giao điểm đầu tiên (1–16). Độ sâu 1 chỉ chiếu sáng trực tiếp bề mặt đục; giá trị cao hơn cho phép thêm lần phản xạ hoặc xuyên kính và có thể lâu hơn. Tắt Chiếu sáng gián tiếp để dùng phản xạ tùy chỉnh hoặc dị hướng.",
+  "render.cpu_path_help": "Tính ánh sáng phản xạ giữa các bề mặt đục và truyền qua các hình kính được hỗ trợ. Cần kết xuất lũy tiến và bóng dò tia. Độ sâu đường đi đếm các bề mặt được chiếu sáng, ranh giới kính và các sự kiện tán xạ từ giao điểm đầu tiên (1–64). Độ sâu 1 chỉ chiếu sáng trực tiếp bề mặt đục; giá trị cao hơn cho phép thêm lần phản xạ hoặc xuyên kính và có thể lâu hơn. Tắt Chiếu sáng gián tiếp để dùng phản xạ tùy chỉnh hoặc dị hướng.",
   "render.cpu_path_lighting": "Chiếu sáng gián tiếp",
   "render.cpu_path_optics_reason": "Các thiết lập được giữ nguyên. Tắt Chiếu sáng gián tiếp để dùng phản xạ tùy chỉnh hoặc dị hướng.",
   "render.cpu_point": "Nguồn sáng điểm",
@@ -5520,6 +5543,7 @@
   "ui.heading_plastic": "CHI TIẾT NHỰA",
   "ui.heading_position": "VỊ TRÍ",
   "ui.heading_prepare": "CHUẨN BỊ",
+  "ui.heading_press_pull": "KÉO/ĐẨY",
   "ui.heading_rectangular_pattern": "SAO CHÉP HÌNH CHỮ NHẬT",
   "ui.heading_revolve": "XOAY TRÒN TẠO KHỐI",
   "ui.heading_right": "HÌNH CHIẾU CẠNH",
@@ -5863,6 +5887,8 @@
   "ui.profiles": "Các biên dạng",
   "ui.project": "Chiếu hình học",
   "ui.project_face_edges_sketch": "Chiếu các cạnh bề mặt vào phác thảo mới",
+  "ui.project_references_construction": "Chiếu tham chiếu thành đường dựng hình",
+  "ui.project_references_construction_note": "Chiếu, Giao, Đưa vào hình học 3D và các cạnh bề mặt của phác thảo mới trên một bề mặt tạo ra đường dựng hình: tham chiếu để vẽ theo, không thuộc biên dạng. Chúng vẫn liên kết với mô hình.",
   "ui.properties": "Thuộc tính cơ lý",
   "ui.properties.copy_matrix": "Sao chép ma trận",
   "ui.properties.first_moments": "Mômen bậc nhất",
@@ -5906,6 +5932,8 @@
   "ui.renderer": "Trình kết xuất hình ảnh (Renderer)",
   "ui.repeat": "Lặp lại",
   "ui.repeat_nothing": "Chưa có gì để lặp lại: hãy bắt đầu một công cụ hoặc hộp thoại trước.",
+  "ui.replace_sketch.from_file": "Từ một tệp thiết kế…",
+  "ui.replace_sketch.no_sketches": "Thiết kế đó không có phác thảo nào để lấy",
   "ui.replace_with_link_done": "Các bản sao hiện đã trở thành các vị trí đặt của thiết kế liên kết.",
   "ui.report_a_bug": "Báo cáo lỗi",
   "ui.report_characters_left_one": "Còn {count} ký tự",

assets/locales/zh.json

@@ -265,6 +265,7 @@
   "Edge": "边",
   "Edges": "边",
   "Edit": "编辑",
+  "Edit Holes": "编辑孔",
   "Edit Profile Sketch": "编辑轮廓草图",
   "Edit shortcuts": "编辑快捷键",
   "Enable rule": "启用规则",
@@ -1206,6 +1207,7 @@
   "cmd.material_properties_directional": "方向弹性模量",
   "cmd.material_properties_validate": "验证物理材料数据",
   "cmd.mesh_convert": "转换网格",
+  "cmd.model_body_features": "列出实体特征",
   "cmd.model_edges": "列出边",
   "cmd.model_faces": "列出面",
   "cmd.model_threads": "列出螺纹",
@@ -1234,8 +1236,11 @@
   "cmd.panel.dismiss": "关闭面板临时预览",
   "cmd.panel.float": "浮动面板",
   "cmd.panel.focus": "聚焦面板",
+  "cmd.panel.focus.next": "聚焦下一个面板",
+  "cmd.panel.focus.previous": "聚焦上一个面板",
   "cmd.panel.list": "列出面板",
   "cmd.panel.move": "移动面板",
+  "cmd.panel.move.next_zone": "将面板移至下一个区域",
   "cmd.panel.native_close": "重新停靠独立窗口中的面板分区",
   "cmd.panel.open": "打开面板",
   "cmd.panel.peek": "临时预览折叠面板",
@@ -1243,6 +1248,12 @@
   "cmd.panel.reset_pair": "重置面板分隔条",
   "cmd.panel.resize": "调整面板分区大小",
   "cmd.panel.resize_pair": "移动面板分隔条",
+  "cmd.panel.sash.down": "向下移动面板分隔条",
+  "cmd.panel.sash.left": "向左移动面板分隔条",
+  "cmd.panel.sash.reset": "重置当前焦点面板的分隔条",
+  "cmd.panel.sash.right": "向右移动面板分隔条",
+  "cmd.panel.sash.up": "向上移动面板分隔条",
+  "cmd.panel.toggle": "切换当前焦点面板的折叠状态",
   "cmd.parameters_add": "添加用户参数",
   "cmd.parameters_change": "更改参数",
   "cmd.parameters_comment": "注释参数",
@@ -1366,6 +1377,7 @@
   "cmd.sketch.construction_line.tangent_external": "过外部点的切线",
   "cmd.sketch.construction_line.tangent_two": "公切线",
   "cmd.sketch.construction_line.vertical": "竖直构造直线",
+  "cmd.sketch.replace": "替换草图",
   "cmd.sketch_arc3d": "三维圆弧",
   "cmd.sketch_arc_center_point": "中心点圆弧",
   "cmd.sketch_arc_tangent": "相切圆弧",
@@ -2016,6 +2028,7 @@
   "help.view.visual_style": "切换模型的绘制方式：带边或不带边的着色、线框，或带隐藏边。用线框看内部，用着色得到干净的外观。",
   "history.sketch_under_constrained": "欠约束（{count} 个自由度）",
   "history.sketch_under_constrained_one": "欠约束（{count} 个自由度）",
+  "hole_folder.applies_to": "更改将应用于 {folder} 中的 {count} 个孔；每个孔保持原位置。",
   "hole_presets.confirm_delete": "确认删除",
   "hole_presets.delete": "删除",
   "hole_presets.delete_prompt": "删除此个人预设？现有孔不会改变。",
@@ -2515,6 +2528,8 @@
   "prefs.bottom_centre": "底部居中",
   "prefs.bottom_right": "右下角",
   "prefs.browser": "浏览器",
+  "prefs.browser_body_features": "实体下显示特征",
+  "prefs.browser_body_features_note": "浏览器中的每个实体都可展开，按时间线顺序显示构建它的时间线特征。",
   "prefs.browser_components_open": "组件初始展开",
   "prefs.browser_components_open_note": "浏览器中的每个组件都像以前一样初始展开，而不是在您展开前保持折叠。",
   "prefs.browser_eye_left": "折叠箭头旁的眼睛图标",
@@ -2555,7 +2570,11 @@
   "prefs.design_tools.degrees": "度",
   "prefs.design_tools.double_click_help": "或就地编辑链接的组件。",
   "prefs.design_tools.ghost": "以虚影显示已移动零件的原位置",
+  "prefs.design_tools.hole_group": "将一起创建的孔分组",
+  "prefs.design_tools.hole_group_help": "一次创建的孔在历史中共用一个文件夹，初始为折叠；展开后可单独编辑每个孔。",
   "prefs.design_tools.hole_moves_help": "再次选择该面会移动孔而非移除孔。",
+  "prefs.design_tools.hole_several": "一个面上多个孔",
+  "prefs.design_tools.hole_several_help": "在面的其他位置选择会再添加一个孔；选择孔会移除该孔。",
   "prefs.design_tools.hole_snaps_help": "面的中点及其圆形边的圆心。",
   "prefs.design_tools.imported_files": "导入的文件",
   "prefs.design_tools.note": "提示",
@@ -2637,6 +2656,8 @@
   "prefs.history": "历史",
   "prefs.history_bar_groups": "将历史栏折叠为分组",
   "prefs.history_bar_groups_note": "在较长的历史中，同一组件的连续特征折叠为一个标签，特征文件夹开始时为折叠状态。插入的 STEP 装配体放入 Group 文件夹。关闭后显示每个特征，文件夹开始时为展开状态，且不创建文件夹。",
+  "prefs.history_folder_kind_icon": "文件夹使用其中特征的图标",
+  "prefs.history_folder_kind_icon_note": "历史中特征全部属于同一类型的文件夹显示该类型的图标。",
   "prefs.history_group_joints": "在历史中将关节分组",
   "prefs.history_group_joints_note": "两个或更多关节显示为一个带数量的按钮，单击即可显示每个关节。关闭后逐个显示每个关节。",
   "prefs.history_origin_bodies": "在顶部显示原点和实体",
@@ -2830,6 +2851,8 @@
   "prefs.select_other_hidden": "使用“选择其他”选择隐藏几何体",
   "prefs.select_other_hidden_help": "开启：包括指针附近的隐藏实体、草图和被遮挡的边。关闭：恢复原来的列表，仅包含指针正下方的可见几何体。",
   "prefs.selecting": "选择",
+  "prefs.shared_panel_layout": "使用共享面板布局",
+  "prefs.shared_panel_layout_help": "在可移动面板中显示现有的浏览器、历史记录和助手。应用首选项后更改生效。",
   "prefs.shift": "Shift",
   "prefs.shift_add_ctrl_toggle": "Shift 仅添加；Ctrl / Cmd 切换选择",
   "prefs.shift_add_note": "开启：Shift 添加，Ctrl / Cmd 切换选择。关闭（默认）：两者均切换选择。",
@@ -3374,7 +3397,7 @@
   "render.cpu_opaque_required": "CPU 光线追踪需要不透明背景。请关闭透明背景。",
   "render.cpu_options_pending": "此CPU面板暂不支持编辑自发光、表面效果、玻璃或各向异性。使用前请清除这些API选项。",
   "render.cpu_path_depth": "路径深度",
-  "render.cpu_path_help": "计算在不透明表面之间反射并穿过受支持玻璃形状的光。需要渐进渲染和光线追踪阴影。路径深度从首次相交开始计算着色表面、玻璃边界和散射事件（1–16）。深度 1 只计算不透明表面的直接照明；更高的值允许更多反射或玻璃穿越，也可能耗时更长。使用自定义反射或各向异性时，请关闭间接照明。",
+  "render.cpu_path_help": "计算在不透明表面之间反射并穿过受支持玻璃形状的光。需要渐进渲染和光线追踪阴影。路径深度从首次相交开始计算着色表面、玻璃边界和散射事件（1–64）。深度 1 只计算不透明表面的直接照明；更高的值允许更多反射或玻璃穿越，也可能耗时更长。使用自定义反射或各向异性时，请关闭间接照明。",
   "render.cpu_path_lighting": "间接照明",
   "render.cpu_path_optics_reason": "设置会保留。使用自定义反射或各向异性时，请关闭间接照明。",
   "render.cpu_point": "点光源",
@@ -5520,6 +5543,7 @@
   "ui.heading_plastic": "塑料",
   "ui.heading_position": "位置",
   "ui.heading_prepare": "准备",
+  "ui.heading_press_pull": "按压拖动",
   "ui.heading_rectangular_pattern": "矩形阵列",
   "ui.heading_revolve": "旋转",
   "ui.heading_right": "右视",
@@ -5863,6 +5887,8 @@
   "ui.profiles": "轮廓",
   "ui.project": "投影",
   "ui.project_face_edges_sketch": "将面的边投影到新草图",
+  "ui.project_references_construction": "将参考投影为构造几何",
+  "ui.project_references_construction_note": "投影、相交、包含三维几何以及在面上新建草图时投影的面边，都会生成构造几何：用于绘图参考，不计入轮廓。它们仍与模型保持关联。",
   "ui.properties": "属性",
   "ui.properties.copy_matrix": "复制矩阵",
   "ui.properties.first_moments": "一阶矩",
@@ -5906,6 +5932,8 @@
   "ui.renderer": "渲染器",
   "ui.repeat": "重复",
   "ui.repeat_nothing": "还没有可重复的操作：请先启动一个工具或对话框。",
+  "ui.replace_sketch.from_file": "从设计文件…",
+  "ui.replace_sketch.no_sketches": "该设计中没有可用的草图",
   "ui.replace_with_link_done": "这些副本现在是链接设计的放置。",
   "ui.report_a_bug": "报告缺陷",
   "ui.report_characters_left_one": "剩余 {count} 个字符",

assets/shaders/viewport.wgsl

@@ -716,14 +716,20 @@ fn lit_color(i: TOut, visibility: f32, base: vec4<f32>) -> vec4<f32> {
     if (dot(n, v) < 0.0) { n = -n; }
     if u.product_lights_meta.x>0.0 {
         var radiance=vec3<f32>(0.0);
+        let albedo=srgb_decode(base.rgb);
         for (var k=0u;k<min(u32(u.product_lights_meta.y),21u);k+=1u) {
-            if u.product_lights[k*4u].w == 4.0 {radiance+=to_linear(base.rgb)*u.product_lights[k*4u+1u].xyz/3.141592653589793;continue;}
+            if u.product_lights[k*4u].w == 4.0 {radiance+=albedo*u.product_lights[k*4u+1u].xyz/3.141592653589793;continue;}
             let sample=product_light_sample(k,i.wp);
-            radiance+=to_linear(base.rgb)*sample[1]*(max(dot(n,sample[0]),0.0)/3.141592653589793);
+            radiance+=albedo*sample[1]*(max(dot(n,sample[0]),0.0)/3.141592653589793);
         }
         let mapped=radiance/(vec3<f32>(1.0)+radiance);
+        // A linear attachment takes linear light as it is; any other is encoded once, as the CPU
+        // image is (decoding the encoded value again through `out_color` would flatten the dark end).
+        if (u.back.w > 0.5) {
+            return vec4<f32>(mapped,base.a);
+        }
         let encoded=select(mapped*12.92,1.055*pow(mapped,vec3<f32>(1.0/2.4))-vec3<f32>(0.055),mapped>vec3<f32>(0.0031308));
-        return out_color(vec4<f32>(encoded,base.a));
+        return vec4<f32>(encoded,base.a);
     }
     let key = normalize(v * 0.8 + vec3<f32>(-0.3, 0.2, 0.6));
     let diff = max(dot(n, key), 0.0);

crates/doc/src/construct.rs

@@ -196,6 +196,45 @@ fn edge_pick<'a>(st: &'a ModelState, at: Vec3, name: &Option<String>) -> Result<
     }
 }
 
+/// The closest point on a polyline to `target`, projecting onto each segment rather than
+/// choosing only its vertices. This keeps an edge pick on the edge between tessellation points.
+fn closest_point_on_polyline(pts: &[Vec3], target: Vec3) -> Option<Vec3> {
+    let mut best: Option<(f64, Vec3)> = None;
+    for w in pts.windows(2) {
+        let (a, b) = (w[0], w[1]);
+        let ab = b - a;
+        let len_sq = ab.dot(ab);
+        let q = if len_sq < 1e-18 {
+            a
+        } else {
+            let t = ((target - a).dot(ab) / len_sq).clamp(0.0, 1.0);
+            a + ab * t
+        };
+        let d = target.dist(q);
+        if best.as_ref().is_none_or(|(bd, _)| d < *bd) {
+            best = Some((d, q));
+        }
+    }
+    best.map(|(_, q)| q)
+}
+
+/// The point on an edge nearest a pick location, projecting onto exact edge geometry
+/// (such as `kernel::edge_circle`) when available, else onto its drawn polyline segments.
+fn edge_point_at_pick(st: &ModelState, pick: Vec3, name: &Option<String>) -> Option<Vec3> {
+    let (b, i, pts) = edge_pick(st, pick, name).ok()?;
+    if let Some(c) = kernel::edge_circle(&b.body, i) {
+        let v = pick - c.center;
+        let v_perp = v - *c.axis * v.dot(*c.axis);
+        if let Some(dir) = v_perp.normalized() {
+            return Some(c.center + dir * c.radius);
+        }
+    }
+    // Until the kernel can project onto any edge geometry (circles are exact above via
+    // kernel::edge_circle), the fallback projects onto the drawn polyline. This is exact for
+    // straight edges and approximates splines within mesh display tolerance.
+    closest_point_on_polyline(&pts, pick)
+}
+
 /// The circle a picked edge lies on, from its exact curve (`kernel::edge_circle`) when the drawn
 /// edge lies on it, else fitted to the drawn points: (centre, unit normal).
 fn edge_circle(b: &ModelBody, index: usize, pts: &[Vec3]) -> Option<(Vec3, Vec3)> {
@@ -743,7 +782,29 @@ pub(crate) fn resolve_geo_plane(ctx: &Ctx, p: &PlaneRef) -> Result<Plane> {
         PlaneRef::AxisPoint { axis, point: at } => {
             let (origin, dir) = line(ctx, axis)?;
             let dir = dir.normalized().ok_or_else(|| bad("the axis has no direction"))?;
-            let delta = point(ctx, at)? - origin;
+            let p = match point(ctx, at) {
+                Ok(p) => {
+                    let delta = p - origin;
+                    let across = delta - dir * delta.dot(dir);
+                    if across.len().is_finite() && across.len() >= 1e-9 {
+                        p
+                    } else if let GeoRef::Edge { at: pick, name } = at.as_ref() {
+                        // When the centre of a circular edge lies on the axis, resolve to the picked point on the edge.
+                        edge_point_at_pick(ctx.st, *pick, name).unwrap_or(p)
+                    } else {
+                        p
+                    }
+                }
+                Err(e) => {
+                    // Non-circular edges are not converted to centres by `point`; resolve to the picked edge point.
+                    if let GeoRef::Edge { at: pick, name } = at.as_ref() {
+                        edge_point_at_pick(ctx.st, *pick, name).ok_or(e)?
+                    } else {
+                        return Err(e);
+                    }
+                }
+            };
+            let delta = p - origin;
             let across = delta - dir * delta.dot(dir);
             if !across.len().is_finite() || across.len() < 1e-9 {
                 return Err(bad("the point is on the axis: pick a point off the axis to define a unique plane"));

crates/doc/src/document.rs

@@ -2294,6 +2294,10 @@ pub struct MeshData {
     pub positions: std::sync::Arc<[f64]>,
     /// Three vertex indices per triangle.
     pub triangles: std::sync::Arc<[u32]>,
+    /// Unit shading normals, x/y/z for each triangle corner. Empty means flat shading.
+    /// Independent of the welded positions and the geometric boundary certificate.
+    #[serde(default, skip_serializing_if = "<[f64]>::is_empty")]
+    pub corner_normals: std::sync::Arc<[f64]>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub color: Option<[f32; 3]>,
 }
@@ -2309,6 +2313,36 @@ impl PartialEq for MeshData {
             && self.color == other.color
             && (Arc::ptr_eq(&self.triangles, &other.triangles) || self.triangles == other.triangles)
             && (Arc::ptr_eq(&self.positions, &other.positions) || self.positions == other.positions)
+            && (Arc::ptr_eq(&self.corner_normals, &other.corner_normals) || self.corner_normals == other.corner_normals)
+    }
+}
+
+impl MeshData {
+    /// Explicitly generate crease-aware shading for an existing imported source.
+    /// Coordinates, triangle indices, topology and body identity remain unchanged.
+    pub fn generate_crease_normals(&mut self, angle_degrees: f64) -> crate::Result<()> {
+        if !angle_degrees.is_finite()
+            || !(0.0..=180.0).contains(&angle_degrees)
+            || !self.positions.len().is_multiple_of(3)
+            || !self.triangles.len().is_multiple_of(3)
+        {
+            return Err(crate::DocError::Invalid("mesh crease angle must be between 0 and 180 degrees with complete triangles".into()));
+        }
+        let allocation = |_| crate::DocError::Invalid("could not reserve mesh normal generation".into());
+        let mut positions = Vec::new();
+        positions.try_reserve_exact(self.positions.len() / 3).map_err(allocation)?;
+        positions.extend(self.positions.as_chunks::<3>().0.iter().map(|p| solidcore_record::Vec3::new(p[0], p[1], p[2])));
+        let mut triangles = Vec::new();
+        triangles.try_reserve_exact(self.triangles.len() / 3).map_err(allocation)?;
+        triangles.extend_from_slice(self.triangles.as_chunks::<3>().0);
+        let mesh = solidcraft_geom::Mesh { positions, triangles, ..Default::default() };
+        let normals = mesh.crease_corner_normals(angle_degrees.to_radians(), None).map_err(crate::DocError::Invalid)?;
+        let count = normals.len().checked_mul(9).ok_or_else(|| crate::DocError::Invalid("mesh normal count overflow".into()))?;
+        let mut values = Vec::new();
+        values.try_reserve_exact(count).map_err(allocation)?;
+        values.extend(normals.iter().flatten().flat_map(|n| [n.x, n.y, n.z]));
+        self.corner_normals = values.into();
+        Ok(())
     }
 }
 

crates/doc/src/eval.rs

@@ -143,7 +143,7 @@ impl ModelBody {
 
     /// Face measurements for joint origins, at their original chord tolerance. Pose changes
     /// and scratch copies share them; a geometry edit makes a new body and cache.
-    pub(crate) fn joint_faces(&self) -> Result<Arc<[kernel::FaceInfo]>> {
+    pub fn joint_faces(&self) -> Result<Arc<[kernel::FaceInfo]>> {
         let measure = || {
             #[cfg(test)]
             cost_tests::count(|c| c.joint_faces += 1);
@@ -1161,6 +1161,18 @@ pub struct Model {
     placement_inputs: Option<placement_reuse::Inputs>,
     /// All evaluated features use supported local inputs; computed with the existing owner index.
     placement_local: bool,
+    /// A failed sketch shown while it is edited ([`Model::hold_failed_sketch`]).
+    held: Option<HeldSketch>,
+}
+
+/// A failed sketch built for its editor (#12085): `shown` is the final state `base` with that
+/// sketch in it. [`Model::state`] gives it only while the results still end in `base`, so the
+/// next evaluation, or anything else that changes the results, lets it go.
+#[derive(Clone, Debug)]
+struct HeldSketch {
+    feature: u64,
+    base: Arc<ModelState>,
+    shown: Arc<ModelState>,
 }
 
 /// Parameters a feature uses directly (inputs, sketch dimensions and the expressions of a
@@ -1212,12 +1224,15 @@ struct ImportDigests {
 struct MeshDigest {
     positions: Arc<[f64]>,
     triangles: Arc<[u32]>,
+    corner_normals: Arc<[f64]>,
     digest: u64,
 }
 
 impl MeshDigest {
     fn matches(&self, mesh: &crate::MeshData) -> bool {
-        Arc::ptr_eq(&self.positions, &mesh.positions) && Arc::ptr_eq(&self.triangles, &mesh.triangles)
+        Arc::ptr_eq(&self.positions, &mesh.positions)
+            && Arc::ptr_eq(&self.triangles, &mesh.triangles)
+            && Arc::ptr_eq(&self.corner_normals, &mesh.corner_normals)
     }
 }
 
@@ -1236,7 +1251,12 @@ impl ImportDigests {
                         .enumerate()
                         .map(|(index, mesh)| {
                             let digest = known.mesh(f.id, index, mesh).unwrap_or_else(|| mesh_content_digest(mesh));
-                            MeshDigest { positions: mesh.positions.clone(), triangles: mesh.triangles.clone(), digest }
+                            MeshDigest {
+                                positions: mesh.positions.clone(),
+                                triangles: mesh.triangles.clone(),
+                                corner_normals: mesh.corner_normals.clone(),
+                                digest,
+                            }
                         })
                         .collect();
                     out.meshes.insert(f.id, digests);
@@ -1265,6 +1285,9 @@ fn mesh_content_digest(mesh: &crate::MeshData) -> u64 {
         coordinate.to_bits().hash(&mut h);
     }
     mesh.triangles.hash(&mut h);
+    for n in mesh.corner_normals.iter() {
+        n.to_bits().hash(&mut h);
+    }
     h.finish()
 }
 
@@ -1356,6 +1379,7 @@ fn feature_json(f: &Feature, steps: &ImportDigests) -> String {
                 digests.push(steps.mesh(f.id, index, mesh).unwrap_or_else(|| mesh_content_digest(mesh)));
                 mesh.positions = Arc::from([]);
                 mesh.triangles = Arc::from([]);
+                mesh.corner_normals = Arc::from([]);
             }
         }
         // Keep the complete definition (including mesh order, names and colors) without
@@ -1647,6 +1671,21 @@ impl PlacementReads {
         }
     }
 
+    /// The bodies To / From Object's stored face names find, each where it is placed: evaluation
+    /// finds a named face by its name ([`with_named_face_points`] fails a feature whose name finds
+    /// none). Everything when a name is missing or empty, finds no one body, or `st` is `None`:
+    /// the face is then found by its point, on whatever body lies there.
+    fn object_faces(&mut self, st: Option<&ModelState>, names: Option<&[String]>) {
+        let bodies: Option<Vec<&str>> = st.zip(names).and_then(|(st, names)| {
+            let first_of_its_name = |b: &&ModelBody| st.body(&b.name).is_some_and(|first| std::ptr::eq(first, *b));
+            names.iter().map(|n| crate::name_lookup::face_body(st, n).filter(first_of_its_name).map(|b| b.name.as_str())).collect()
+        });
+        match bodies {
+            Some(bodies) => bodies.into_iter().for_each(|b| self.placed_body(st, b)),
+            None => self.all = true,
+        }
+    }
+
     /// The same target selection as `apply_traced`, expanded only over the timeline input.
     fn drawn_targets(&mut self, st: Option<&ModelState>, f: &Feature) {
         let Some(st) = st else {
@@ -1826,11 +1865,22 @@ fn placement_digest(doc: &Document, f: &Feature, st: Option<&ModelState>) -> u64
             }
         }
     }
+    // The faces To / From Object names, in `face_points` order.
+    let object_names = match &f.kind {
+        FeatureKind::Extrude { extent, .. } => usize::from(extent.to.is_some()) + usize::from(extent.from.is_some()),
+        FeatureKind::Revolve { to, .. } => usize::from(to.is_some()),
+        _ => 0,
+    };
     match &f.kind {
-        // To / From Object finds its target where that target's component is placed (#928),
-        // over every body.
-        FeatureKind::Extrude { extent, .. } if extent.to.is_some() || extent.from.is_some() => reads.all = true,
-        FeatureKind::Revolve { to: Some(_), .. } => reads.all = true,
+        // To / From Object finds its target where the target's body is placed (#928): only that
+        // body's placement, not every part's (#6325). Its tools meet their targets as other
+        // joins and cuts do.
+        kind if object_names > 0 => {
+            reads.object_faces(st, f.face_names.get(..object_names));
+            if drawn_tools_change_bodies(kind) {
+                reads.drawn_targets(st, f);
+            }
+        }
         // A mirror of placed bodies follows the placements it was picked at and its own component's
         // frame, not every occurrence: moving an unrelated one leaves it (and its cache) alone.
         FeatureKind::Mirror { placements, bodies, .. } if !placements.is_empty() => return mirror_placements_digest(doc, f, placements, bodies),
@@ -1978,9 +2028,56 @@ impl Model {
 
     /// The final model state.
     pub fn state(&self) -> Arc<ModelState> {
+        let last = self.evaluated_state();
+        match &self.held {
+            Some(held) if Arc::ptr_eq(&held.base, &last) => held.shown.clone(),
+            _ => last,
+        }
+    }
+
+    /// The state after the last feature evaluated, without a failed sketch held for its editor.
+    fn evaluated_state(&self) -> Arc<ModelState> {
         self.results.iter().rev().find(|r| !r.skipped).map(|r| r.state.clone()).unwrap_or_else(|| self.empty.clone())
     }
 
+    /// Show the sketch `feature` while it is edited although it failed (#12085): a link whose
+    /// named face or edge is gone fails the sketch, so the evaluation keeps no sketch for it, and
+    /// its editor had nothing to show or repair. Here the sketch is built as it is evaluated, but
+    /// with such a link marked lost and kept where it was (no other face or edge is taken for
+    /// it), and added to the final state only: the sketch's result keeps its error and the
+    /// features after it still fail. `None`, a sketch that did not fail, or one that fails for
+    /// another reason too, shows nothing more. Returns whether a held sketch is shown.
+    pub fn hold_failed_sketch(&mut self, doc: &Document, feature: Option<u64>) -> bool {
+        let Some(id) = feature else {
+            self.held = None;
+            return false;
+        };
+        let base = self.evaluated_state();
+        if self.held.as_ref().is_some_and(|held| held.feature == id && Arc::ptr_eq(&held.base, &base)) {
+            return true;
+        }
+        self.held = None;
+        if base.sketch(id).is_some() || !self.result(id).is_some_and(|r| r.error.is_some() && !r.skipped && !r.stale) {
+            return false;
+        }
+        let Some(f) = doc.feature(id) else { return false };
+        let FeatureKind::Sketch { plane, sketch } = &f.kind else { return false };
+        let mut next = (*self.state_before(id)).clone();
+        let vals = evaluation_values(doc).0;
+        let mut warning = None;
+        let built = kernel::guard(&f.name, || {
+            let _frames = ToolFrames::install(doc, f, &next);
+            eval_sketch(doc, &vals, f, plane, sketch, &mut next, &mut warning, crate::project::LostNames::Mark)
+                .map_err(|e| kernel::KernelError::Failed(e.to_string()))
+        });
+        let Some(solved) = built.ok().and_then(|()| next.sketches.iter().find(|s| s.feature == id).cloned()) else { return false };
+        let mut shown = (*base).clone();
+        shown.sketches.retain(|s| s.feature != id);
+        shown.sketches.push(solved);
+        self.held = Some(HeldSketch { feature: id, base, shown: Arc::new(shown) });
+        true
+    }
+
     /// State just before the feature with this id (for editing a sketch in context).
     pub fn state_before(&self, id: u64) -> Arc<ModelState> {
         let Some(i) = self.results.iter().position(|r| r.id == id) else { return self.state() };
@@ -2144,6 +2241,10 @@ impl Model {
 
     /// Re-evaluate the document, reusing results up to the first changed feature.
     pub fn evaluate(&mut self, doc: &Document) {
+        // A failed sketch held for its editor is built again from the evaluated design: when the
+        // sketch and every feature after it fail, the results end in the state they ended in
+        // before, which would keep showing the sketch as it was before the edit.
+        self.held = None;
         let _span = solidcraft_profile::span("doc", "evaluate");
         self.placement_inputs = None;
         self.fingerprinted = None;
@@ -6932,6 +7033,22 @@ fn replay(
                 instances.push(start..copies.len());
             }
         }
+        // A cut or intersect copy with no named targets, made where the pattern's own component
+        // has no body for it, works on the bodies of its source's component, as the source did
+        // (#12996). A pattern whose component has bodies cuts them, as before. The same scope
+        // counts misses, takes sheet cuts and applies the copies.
+        let scoped;
+        let f = if matches!(op, Operation::Cut | Operation::Intersect)
+            && targets.is_empty()
+            && f.participants.is_empty()
+            && src.component != f.component
+            && !st.bodies.iter().any(|b| b.component == f.component || b.feature == f.id)
+        {
+            scoped = Feature { component: src.component, ..f.clone() };
+            &scoped
+        } else {
+            f
+        };
         if op == Operation::Cut {
             let (m, t) = count_copy_misses(st, f, &targets, &copies, &instances, &axes);
             missed += m;
@@ -7380,72 +7497,7 @@ fn eval_feature(
         | FeatureKind::ReplaceFace { .. }
         | FeatureKind::Align { .. }
         | FeatureKind::Remove { .. } => more::eval(doc, vals, f, st, warning),
-        FeatureKind::Sketch { plane, sketch } => {
-            let anchor = crate::face_anchor::plane_face_anchor(plane);
-            let fst = match anchor {
-                Some(anchor) => crate::state_in_face_anchor_frame(doc, st, anchor, f.component)?,
-                // A sketch that reads no geometry (a fixed plane, no projections) needs no other
-                // component's bodies moved into its frame: placing every body of a large
-                // assembly again is what made each sketch edit as slow as the design is big.
-                None if !plane_reads_geometry(plane) && sketch.links.is_empty() => std::borrow::Cow::Borrowed(st),
-                None => state_in_frame(doc, st, f.component)?,
-            };
-            // A further placement a link reads is placed in its frame too (#9957).
-            let named: Vec<&str> = sketch.links.iter().flat_map(|l| l.source.bodies()).collect();
-            let fst = match anchor.map(|anchor| anchor.author_frame(doc, f.component)) {
-                _ if named.is_empty() => fst,
-                Some(Ok(frame)) => with_placed_copies(doc, st, fst, &frame, &named),
-                Some(Err(_)) => fst,
-                None => with_placed_copies(doc, st, fst, &doc.component_transform(f.component), &named),
-            };
-            let (plane, face_warning) = match (anchor, plane) {
-                (Some(_), plane) => doc.resolve_attached_plane_noted(vals, plane, f.component, st, &fst)?,
-                // A flat face of a sheet: the panel's exact plane, from its flat region and fold.
-                (None, plane) if crate::sheet::plane_sheet_face(plane).is_some() => {
-                    (doc.resolve_plane_in(vals, &sheet_face_plane_in_frame(doc, st, f.component, plane)?, 0, Some(&fst))?, None)
-                }
-                (None, PlaneRef::Face { plane: picked, at, name, anchor: None }) => face_plane(&fst, picked, *at, name.as_deref())?,
-                (None, other) => (doc.resolve_plane_in(vals, other, 0, Some(&fst))?, None),
-            };
-            let mut sk = sketch.clone();
-            // A text's outlines are rebuilt from its numbers when the links are refreshed: the
-            // ones its expressions give come first.
-            doc.apply_text_values(vals, &mut sk)?;
-            let mut warns = match anchor {
-                Some(anchor) => crate::project::refresh_face_anchor_links(doc, vals, &fst, &plane, &mut sk, anchor)?,
-                None => crate::project::refresh_links(doc, vals, &fst, &plane, &mut sk)?,
-            };
-            drop(fst);
-            sk.refresh_offsets()?;
-            if let Some(w) = face_warning {
-                warns.insert(0, w);
-            }
-            // The stored sketch is solved for its stored values, with its links where they
-            // were stored: a link that moved must not change the side a dimension from it is on.
-            let stored = sk.driving_values();
-            let report = doc.solve_sketch(vals, &mut sk, &stored, Some(sketch))?;
-            if !report.keeps_orientation() {
-                warns.insert(0, report.failure(|f| format!("the sketch constraints conflict ({f})")));
-            } else {
-                // The solve may have moved the curve a text runs along.
-                warns.extend(crate::project::relay_path_texts(&mut sk));
-            }
-            if !warns.is_empty() {
-                *warning = Some(warns.join("; "));
-            }
-            sk.validate_periodic_splines()?;
-            // A group of touching curves too large to search whole says so, rather than
-            // leaving profiles out silently (#6896).
-            let search = solidcraft_sketch::find_profiles_checked(&sk);
-            if search.incomplete {
-                append_warning(warning, profiles_cut_short_note());
-            }
-            let profiles = search.profiles;
-            let ends = solidcraft_sketch::loose_ends(&sk);
-            st.sketches.retain(|s| s.feature != f.id);
-            st.sketches.push(Arc::new(SolvedSketch { feature: f.id, name: f.name.clone(), plane, sketch: sk, report, profiles, ends }));
-            Ok(())
-        }
+        FeatureKind::Sketch { plane, sketch } => eval_sketch(doc, vals, f, plane, sketch, st, warning, crate::project::LostNames::Fail),
         FeatureKind::Extrude { operation, targets, .. }
         | FeatureKind::Pipe { operation, targets, .. }
         | FeatureKind::Revolve { operation, targets, .. }
@@ -8264,6 +8316,88 @@ fn eval_feature(
     }
 }
 
+/// A sketch feature: its links refreshed against the model before it, solved, its profiles
+/// found. `lost_names` says what a link whose named face or edge is gone does: the evaluation
+/// fails the sketch ([`crate::project::LostNames::Fail`]); a failed sketch shown for editing
+/// marks the link lost instead ([`Model::hold_failed_sketch`]).
+#[allow(clippy::too_many_arguments)]
+fn eval_sketch(
+    doc: &Document,
+    vals: &BTreeMap<String, Value>,
+    f: &Feature,
+    plane: &PlaneRef,
+    sketch: &solidcraft_sketch::Sketch,
+    st: &mut ModelState,
+    warning: &mut Option<String>,
+    lost_names: crate::project::LostNames,
+) -> Result<()> {
+    let anchor = crate::face_anchor::plane_face_anchor(plane);
+    let fst = match anchor {
+        Some(anchor) => crate::state_in_face_anchor_frame(doc, st, anchor, f.component)?,
+        // A sketch that reads no geometry (a fixed plane, no projections) needs no other
+        // component's bodies moved into its frame: placing every body of a large
+        // assembly again is what made each sketch edit as slow as the design is big.
+        None if !plane_reads_geometry(plane) && sketch.links.is_empty() => std::borrow::Cow::Borrowed(st),
+        None => state_in_frame(doc, st, f.component)?,
+    };
+    // A further placement a link reads is placed in its frame too (#9957).
+    let named: Vec<&str> = sketch.links.iter().flat_map(|l| l.source.bodies()).collect();
+    let fst = match anchor.map(|anchor| anchor.author_frame(doc, f.component)) {
+        _ if named.is_empty() => fst,
+        Some(Ok(frame)) => with_placed_copies(doc, st, fst, &frame, &named),
+        Some(Err(_)) => fst,
+        None => with_placed_copies(doc, st, fst, &doc.component_transform(f.component), &named),
+    };
+    let (plane, face_warning) = match (anchor, plane) {
+        (Some(_), plane) => doc.resolve_attached_plane_noted(vals, plane, f.component, st, &fst)?,
+        // A flat face of a sheet: the panel's exact plane, from its flat region and fold.
+        (None, plane) if crate::sheet::plane_sheet_face(plane).is_some() => {
+            (doc.resolve_plane_in(vals, &sheet_face_plane_in_frame(doc, st, f.component, plane)?, 0, Some(&fst))?, None)
+        }
+        (None, PlaneRef::Face { plane: picked, at, name, anchor: None }) => face_plane(&fst, picked, *at, name.as_deref())?,
+        (None, other) => (doc.resolve_plane_in(vals, other, 0, Some(&fst))?, None),
+    };
+    let mut sk = sketch.clone();
+    // A text's outlines are rebuilt from its numbers when the links are refreshed: the
+    // ones its expressions give come first.
+    doc.apply_text_values(vals, &mut sk)?;
+    let mut warns = match (anchor, lost_names) {
+        (Some(anchor), crate::project::LostNames::Fail) => crate::project::refresh_face_anchor_links(doc, vals, &fst, &plane, &mut sk, anchor)?,
+        (None, crate::project::LostNames::Fail) => crate::project::refresh_links(doc, vals, &fst, &plane, &mut sk)?,
+        (anchor, crate::project::LostNames::Mark) => crate::project::refresh_links_marking_lost(doc, vals, &fst, &plane, &mut sk, anchor)?,
+    };
+    drop(fst);
+    sk.refresh_offsets()?;
+    if let Some(w) = face_warning {
+        warns.insert(0, w);
+    }
+    // The stored sketch is solved for its stored values, with its links where they
+    // were stored: a link that moved must not change the side a dimension from it is on.
+    let stored = sk.driving_values();
+    let report = doc.solve_sketch(vals, &mut sk, &stored, Some(sketch))?;
+    if !report.keeps_orientation() {
+        warns.insert(0, report.failure(|f| format!("the sketch constraints conflict ({f})")));
+    } else {
+        // The solve may have moved the curve a text runs along.
+        warns.extend(crate::project::relay_path_texts(&mut sk));
+    }
+    if !warns.is_empty() {
+        *warning = Some(warns.join("; "));
+    }
+    sk.validate_periodic_splines()?;
+    // A group of touching curves too large to search whole says so, rather than
+    // leaving profiles out silently (#6896).
+    let search = solidcraft_sketch::find_profiles_checked(&sk);
+    if search.incomplete {
+        append_warning(warning, profiles_cut_short_note());
+    }
+    let profiles = search.profiles;
+    let ends = solidcraft_sketch::loose_ends(&sk);
+    st.sketches.retain(|s| s.feature != f.id);
+    st.sketches.push(Arc::new(SolvedSketch { feature: f.id, name: f.name.clone(), plane, sketch: sk, report, profiles, ends }));
+    Ok(())
+}
+
 /// `copy`, a moved copy of `source` (instance `instance` of a pattern or mirror): its faces are
 /// named after the source's.
 fn moved_copy(source: &ModelBody, copy: Body, instance: usize) -> Traced {
@@ -8276,7 +8410,17 @@ fn mesh_bodies(meshes: &[crate::MeshData]) -> Result<Vec<(String, Body)>> {
     for m in meshes {
         let positions: Vec<Vec3> = m.positions.as_chunks::<3>().0.iter().map(|c| Vec3::new(c[0], c[1], c[2])).collect();
         let triangles: Vec<[u32; 3]> = m.triangles.as_chunks::<3>().0.to_vec();
-        let b = kernel::mesh_body(&positions, &triangles).map_err(|e| DocError::Invalid(format!("mesh `{}`: {e}", m.name)))?;
+        if !m.corner_normals.is_empty() && m.corner_normals.len() != m.triangles.len().saturating_mul(3) {
+            return Err(DocError::Invalid(format!("mesh `{}`: invalid shading normal count", m.name)));
+        }
+        let normals: Vec<[Vec3; 3]> = m
+            .corner_normals
+            .as_chunks::<9>()
+            .0
+            .iter()
+            .map(|c| [Vec3::new(c[0], c[1], c[2]), Vec3::new(c[3], c[4], c[5]), Vec3::new(c[6], c[7], c[8])])
+            .collect();
+        let b = kernel::mesh_body_with_normals(&positions, &triangles, &normals).map_err(|e| DocError::Invalid(format!("mesh `{}`: {e}", m.name)))?;
         out.push((m.name.clone(), b.with_color(m.color)));
     }
     Ok(out)
@@ -8739,6 +8883,7 @@ impl PlacedBodies {
             let mut fresh = ModelBody::new(name.to_string(), placed.body.clone(), b.feature);
             fresh.mesh = placed.mesh.clone();
             fresh.measured = placed.measured.clone();
+            fresh.joint_faces = placed.joint_faces.clone();
             fresh.mesh_placement = placed.mesh_placement.clone();
             fresh.plan = placed.plan.clone();
             fresh.plan_mesh = placed.plan_mesh.clone();

crates/doc/src/eval_cost_tests.rs

@@ -656,6 +656,126 @@ fn a_tool_cutting_another_part_cuts_again_when_that_part_moves() {
     assert!((volume(&model, &body) - (400.0 - 16.0)).abs() < 1e-6, "{}", volume(&model, &body));
 }
 
+/// A root design with two 10 x 10 x 4 mm plates, "Plate" at the origin and "Other" 30 mm along Y,
+/// and a sketch on origin plane `plane` of the rectangle `profile` spans (opposite corners, in mm):
+/// (the plate part, the other part, the sketch).
+fn two_plates_and_a_sketch(doc: &mut Document, plane: &str, profile: [Vec2; 2]) -> (u64, u64, u64) {
+    let plate = doc.add_component(Some("Plate"), 0).unwrap();
+    let other = doc.add_component(Some("Other"), 0).unwrap();
+    place(doc, other, rigid(Vec3::new(0.0, 30.0, 0.0), Vec3::ZERO, Vec3::Z, 0.0));
+    plate_with_holes(doc, other, other, 0);
+    plate_with_holes(doc, plate, plate, 0);
+    let mut sk = Sketch::new();
+    let [a, c] = profile;
+    let p = [a, Vec2::new(c.x, a.y), c, Vec2::new(a.x, c.y)].map(|q| sk.add_point(q, None).unwrap());
+    for k in 0..4 {
+        sk.add_line_pts(p[k], p[(k + 1) % 4], None).unwrap();
+    }
+    let sketch = doc.add_feature(FeatureKind::Sketch { plane: PlaneRef::Origin { name: plane.into() }, sketch: sk }, None).unwrap();
+    (plate, other, sketch)
+}
+
+/// `kind` added to the root with its face points named after the faces under them, as the
+/// command that makes it names them.
+fn add_named(doc: &mut Document, kind: FeatureKind) -> u64 {
+    let mut model = Model::new();
+    model.evaluate(doc);
+    let names = face_point_names(doc, &model.state(), &kind, 0).unwrap();
+    assert!(names.iter().all(|n| !n.is_empty()), "{names:?}");
+    let id = doc.add_feature(kind, None).unwrap();
+    doc.feature_mut(id).unwrap().face_names = names;
+    id
+}
+
+/// An extrude in the root from the top of the plate (z 4) 6 mm up, over 2 to 8 mm on X and Y.
+fn extrude_from_the_plate(doc: &mut Document) -> (u64, u64, u64) {
+    let (plate, other, sketch) = two_plates_and_a_sketch(doc, "XY", [Vec2::new(2.0, 2.0), Vec2::new(8.0, 8.0)]);
+    let kind = FeatureKind::Extrude {
+        thin: None,
+        sketch: SketchId(sketch),
+        profiles: ProfileSel::All,
+        extent: serde_json::from_value(serde_json::json!({"distance": "6", "from": [5.0, 5.0, 4.0]})).unwrap(),
+        operation: Operation::NewBody,
+        targets: vec![],
+    };
+    (plate, other, add_named(doc, kind))
+}
+
+/// Where the body feature `id` made has its centre.
+fn centroid_of(model: &Model, id: u64) -> Vec3 {
+    let st = model.state();
+    kernel::measure(&st.bodies.iter().find(|b| b.feature == id).unwrap().body).unwrap().centroid
+}
+
+/// An extrude from a face of the plate reads where the plate is, and nothing else (#6325): a
+/// joint moving another part leaves its result, and every result after it, as it was.
+#[test]
+fn an_extrude_from_its_own_part_keeps_its_result_when_another_part_moves() {
+    let mut doc = Document::new("from object");
+    let (plate, other, extrude) = extrude_from_the_plate(&mut doc);
+    let mut model = Model::new();
+    model.evaluate(&doc);
+    assert!(model.results.iter().all(|r| r.error.is_none()), "{:?}", model.results.iter().find(|r| r.error.is_some()));
+    assert!((centroid_of(&model, extrude).z - 7.0).abs() < 1e-6, "{:?}", centroid_of(&model, extrude));
+    place(&mut doc, other, rigid(Vec3::new(0.0, 40.0, 3.0), Vec3::ZERO, Vec3::Z, 0.0));
+    model.evaluate(&doc);
+    assert_eq!(model.last_recomputed, 0);
+    // The plate lifted 5 mm: the extrude starts on its top where it is now (#928).
+    place(&mut doc, plate, rigid(Vec3::new(0.0, 0.0, 5.0), Vec3::ZERO, Vec3::Z, 0.0));
+    model.evaluate(&doc);
+    assert_eq!(model.last_recomputed, 1);
+    assert!((centroid_of(&model, extrude).z - 12.0).abs() < 1e-6, "{:?}", centroid_of(&model, extrude));
+}
+
+/// A revolve To a face of the plate, as the extrude from it: it turns again only when the plate
+/// moves.
+#[test]
+fn a_revolve_to_its_own_part_keeps_its_result_when_another_part_moves() {
+    let mut doc = Document::new("revolve to object");
+    let (plate, other, sketch) = two_plates_and_a_sketch(&mut doc, "XZ", [Vec2::new(12.0, 0.0), Vec2::new(15.0, 2.0)]);
+    let kind = FeatureKind::Revolve {
+        sketch: SketchId(sketch),
+        profiles: ProfileSel::All,
+        axis: AxisRef::SketchAxis { axis: "y".into() },
+        angle: "90 deg".into(),
+        operation: Operation::NewBody,
+        targets: vec![],
+        angle2: None,
+        symmetric: false,
+        convention: Default::default(),
+        to: Some(serde_json::from_value(serde_json::json!([5.0, 5.0, 4.0])).unwrap()),
+    };
+    let revolve = add_named(&mut doc, kind);
+    let mut model = Model::new();
+    model.evaluate(&doc);
+    assert!(model.results.iter().all(|r| r.error.is_none()), "{:?}", model.results.iter().find(|r| r.error.is_some()));
+    let turned = volume(&model, &model.state().bodies.iter().find(|b| b.feature == revolve).unwrap().name.clone());
+    place(&mut doc, other, rigid(Vec3::new(0.0, 40.0, 3.0), Vec3::ZERO, Vec3::Z, 0.0));
+    model.evaluate(&doc);
+    assert_eq!(model.last_recomputed, 0);
+    // The plate turned a quarter about Z: the revolve turns to its top where it is now.
+    place(&mut doc, plate, rigid(Vec3::ZERO, Vec3::ZERO, Vec3::Z, std::f64::consts::FRAC_PI_2));
+    model.evaluate(&doc);
+    assert_eq!(model.last_recomputed, 1);
+    let now = volume(&model, &model.state().bodies.iter().find(|b| b.feature == revolve).unwrap().name.clone());
+    assert!((now - turned).abs() > 1.0, "{turned} then {now}");
+}
+
+/// A From face without a name is found by its point, on whatever body lies there: moving any
+/// part extrudes again.
+#[test]
+fn an_extrude_from_a_face_without_a_name_extrudes_again_when_any_part_moves() {
+    let mut doc = Document::new("from a point");
+    let (_, other, extrude) = extrude_from_the_plate(&mut doc);
+    doc.feature_mut(extrude).unwrap().face_names.clear();
+    let mut model = Model::new();
+    model.evaluate(&doc);
+    assert!((centroid_of(&model, extrude).z - 7.0).abs() < 1e-6, "{:?}", centroid_of(&model, extrude));
+    place(&mut doc, other, rigid(Vec3::new(0.0, 40.0, 3.0), Vec3::ZERO, Vec3::Z, 0.0));
+    model.evaluate(&doc);
+    assert_eq!(model.last_recomputed, 1);
+}
+
 #[test]
 fn a_body_is_measured_once_while_it_stays_the_same() {
     let mut doc = Document::new("measured once");
@@ -791,6 +911,7 @@ fn shared_imported_mesh_inputs_keep_payload_identity_and_invalidate_replacements
                     positions: Arc::from([0., 0., 0., 1., 0., 0., 0., 1., 0.]),
                     triangles: Arc::from([0, 1, 2]),
                     color: None,
+                    corner_normals: Default::default(),
                 }],
             },
             None,
@@ -804,7 +925,7 @@ fn shared_imported_mesh_inputs_keep_payload_identity_and_invalidate_replacements
     Arc::make_mut(&mut doc).occurrences[0].transform = rigid(Vec3::new(10., 0., 0.), Vec3::ZERO, Vec3::Z, 0.3);
     assert!(!model.evaluate_shared(&doc));
     assert!(Arc::ptr_eq(&original, &model.state()));
-    for edit in 0..5 {
+    for edit in 0..6 {
         let FeatureKind::MeshImport { meshes, .. } = &mut Arc::make_mut(&mut doc).feature_mut(feature).unwrap().kind else { panic!("mesh") };
         let mesh = &mut meshes[0];
         match edit {
@@ -812,6 +933,7 @@ fn shared_imported_mesh_inputs_keep_payload_identity_and_invalidate_replacements
             1 => Arc::make_mut(&mut mesh.triangles).swap(1, 2),
             2 => mesh.color = Some([0.2, 0.4, 0.6]),
             3 => mesh.name = "Renamed".into(),
+            4 => mesh.corner_normals = Arc::from([0., 1., 1., 0., 1., 1., 0., 1., 1.]),
             _ => mesh.positions = Arc::from(mesh.positions.to_vec()),
         }
         assert!(model.evaluate_shared(&doc), "mesh edit {edit} must invalidate");
@@ -924,6 +1046,7 @@ fn comparing_a_copied_mesh_does_not_read_its_shared_arrays() {
         positions: Arc::from([0., 0., 0., 1., 0., 0., 0., 1., f64::NAN]),
         triangles: Arc::from([0, 1, 2]),
         color: None,
+        corner_normals: Default::default(),
     };
     let copy = mesh.clone();
     assert!(copy == mesh, "a copy shares the arrays and is the same mesh without reading them");
@@ -1651,6 +1774,7 @@ fn imported_meshes() -> Document {
             positions: [0.0, 0.0, 0.0, 2.0, 0.0, 0.0, 0.0, 3.0, 0.0, 0.0, 0.0, 4.0].into(),
             triangles: [0, 2, 1, 0, 1, 3, 0, 3, 2, 1, 2, 3].into(),
             color: Some([0.2, 0.4, 0.6]),
+            corner_normals: Default::default(),
         })
         .collect();
     let id = doc.add_feature(FeatureKind::MeshImport { file: "tetrahedra.stl".into(), meshes }, Some("Meshes")).unwrap();
@@ -1682,6 +1806,16 @@ fn same_as_fresh(doc: &Document, model: &Model) {
 #[test]
 fn unchanged_mesh_payloads_are_not_read_again_for_rigid_motion() {
     let mut doc = imported_meshes();
+    for mesh in meshes_mut(&mut doc) {
+        mesh.generate_crease_normals(10.0).unwrap();
+        assert!(!mesh.corner_normals.is_empty());
+    }
+    let compact: serde_json::Value = serde_json::from_str(&super::feature_json(&doc.features[0], &super::ImportDigests::default())).unwrap();
+    for mesh in compact[0]["meshes"].as_array().unwrap() {
+        assert_eq!(mesh["positions"], serde_json::json!([]));
+        assert_eq!(mesh["triangles"], serde_json::json!([]));
+        assert!(mesh.get("corner_normals").is_none(), "the fingerprint must hash the retained digest without serializing shading payloads");
+    }
     let mut model = Model::new();
     assert_eq!(counted(|| model.evaluate(&doc)).mesh_digested, 2);
     for k in 1..5 {

crates/doc/src/eval_thread.rs

@@ -1122,4 +1122,31 @@ mod tests {
         // The square stop leaves about half a pitch's worth of groove uncut: well over a mm³.
         assert!(square > trimmed + 1.0, "{square} vs {trimmed}");
     }
+
+    /// A modelled thread on one hole leaves the other hole's wall a cylinder to thread: the
+    /// second hole still takes its thread (#11367).
+    ///
+    /// The modelled thread cuts the body, and the cut must not take the body's other cylinders
+    /// with it: the second hole's wall is still a cylinder, so it still takes a thread, modelled
+    /// or cosmetic.
+    #[test]
+    fn a_modelled_thread_leaves_the_next_hole_a_cylinder_to_thread() {
+        // An 80 x 80 x 20 mm block with two 5 mm holes.
+        let block = kernel::box_solid(Vec3::new(-40.0, -40.0, 0.0), Vec3::new(40.0, 40.0, 20.0)).unwrap();
+        let hole = |x: f64| kernel::cylinder(Vec3::new(x, 0.0, -1.0), Vec3::new(0.0, 0.0, 1.0), 2.5, 22.0).unwrap();
+        let mut body = kernel::boolean(&block, &hole(-20.0), BoolOp::Cut).unwrap().unwrap();
+        body = kernel::boolean(&body, &hole(20.0), BoolOp::Cut).unwrap().unwrap();
+        let mut st = ModelState::default();
+        st.bodies.push(ModelBody::new("Part".into(), body, 1));
+        let ask = ThreadAsk { designation: Some("M6"), ..ask() };
+        // The first hole takes a modelled M6 thread.
+        let on = thread_on(&st, 1, Vec3::new(-17.5, 0.0, 10.0), &ask).unwrap();
+        cut(&mut st, on, (ThreadTip::None, None, None)).unwrap();
+        // The second hole's wall is still a cylinder: it takes a thread too.
+        let on = thread_on(&st, 1, Vec3::new(22.5, 0.0, 10.0), &ask);
+        assert!(on.is_ok(), "the second hole still has a cylinder to thread: {:?}", on.err());
+        // And a modelled one cuts there as well.
+        let on = thread_on(&st, 1, Vec3::new(22.5, 0.0, 10.0), &ask).unwrap();
+        assert!(cut(&mut st, on, (ThreadTip::None, None, None)).is_ok());
+    }
 }

crates/doc/src/expr.rs

@@ -982,6 +982,12 @@ fn call(f: &str, args: &[Value], d: Defaults) -> Result<Value, DocError> {
             // Round in the value's own default unit (round(2.4 in) = 2 in for an inch parameter).
             let scale = scale_bare(Value::num(1.0), a.len, a.ang, d);
             let x = if scale != 0.0 { a.v / scale } else { a.v };
+            // Unit conversions leave a rounding error of an ulp or two (`3 in / 1 in` is
+            // 2.9999999999999996): a value that close to a whole number is that number, so `floor`
+            // does not drop to 2. The tolerance is relative to the whole number, so a tiny value
+            // never snaps to 0, and it stays under 1/8 so no real fraction is absorbed.
+            let nearest = x.round();
+            let x = if (x - nearest).abs() <= (4.0 * f64::EPSILON * nearest.abs()).min(0.125) { nearest } else { x };
             let r = match f {
                 "floor" => x.floor(),
                 "ceil" => x.ceil(),
@@ -1444,6 +1450,43 @@ mod tests {
         }
     }
 
+    /// `floor`, `ceil`, `trunc` and `round` work on the number a person typed, not on float noise:
+    /// `3 in / 1 in` is 2.9999999999999996 in floats, and `floor` of it must still be 3.
+    #[test]
+    fn rounding_functions_ignore_float_noise() {
+        for (e, want) in [("floor(3 in / 1 in)", 3.0), ("ceil(3 in / 1 in)", 3.0), ("trunc(3 in / 1 in)", 3.0), ("floor(-3 in / 1 in)", -3.0)] {
+            assert_eq!(ev(e, Kind::Unitless).unwrap(), want, "{e}");
+        }
+        let d = Defaults { len: 25.4, ang: std::f64::consts::PI / 180.0 };
+        let look = |_: &str| Err(DocError::Expr("no parameters".into()));
+        for e in ["floor(3 in)", "ceil(3 in)", "trunc(3 in)", "round(3 in)"] {
+            let got = eval_with_defaults(e, &look, d).unwrap().to_kind_in(Kind::Length, d).unwrap();
+            assert!((got - 76.2).abs() < 1e-9, "{e} gave {got}");
+        }
+        let got = eval_with_defaults("floor(30 deg)", &look, Defaults::default()).unwrap().to_kind(Kind::Angle).unwrap();
+        assert!((got - 30f64.to_radians()).abs() < 1e-9, "floor(30 deg) gave {got}");
+        // A real fraction still rounds the way its name says, however small, and large values keep working.
+        for (e, want) in [
+            ("floor(2.9999)", 2.0),
+            ("ceil(3.0001)", 4.0),
+            ("floor(100.99999995)", 100.0),
+            ("ceil(100.00000005)", 101.0),
+            ("floor(1000000000.7)", 1_000_000_000.0),
+            ("ceil(1000000000.7)", 1_000_000_001.0),
+            ("trunc(1000000000.7)", 1_000_000_000.0),
+            ("round(1000000000.7)", 1_000_000_001.0),
+            ("ceil(1e-16)", 1.0),
+            ("floor(-1e-16)", -1.0),
+            ("trunc(1e-16)", 0.0),
+            ("trunc(-1e-16)", 0.0),
+            ("round(1e-16)", 0.0),
+            ("round(-1e-16)", 0.0),
+            ("floor(1000000000000000.5)", 1_000_000_000_000_000.0),
+        ] {
+            assert_eq!(ev(e, Kind::Unitless).unwrap(), want, "{e}");
+        }
+    }
+
     /// A count from a length (`(L - 20) / 210`, the 210 read as unit-less) names the fix (#5901).
     #[test]
     fn a_length_where_a_count_is_expected_says_to_divide_by_a_length() {

crates/doc/src/format/pending/opus-quality.rs

@@ -0,0 +1,33 @@
+//! Imported mesh sources may save optional `corner_normals`: nine f64 values per
+//! triangle, independent of positions, topology and optical boundary certification.
+//! Missing/empty normals retain the previous flat shading. OBJ `vn` and `s` import
+//! preserve authored corner normals and smoothing groups. Explicit crease generation
+//! stores only shading metadata and preserves original coordinates and triangle indices.
+//! Older released readers warn about this format and retain fields they cannot read.
+//!
+//! Render jobs may save opt-in `texture_filtering`; omission/false preserves LOD0
+//! texture sampling. Supported consumers use the captured texture's mip chain and
+//! ray footprint without changing source image identity or source color semantics.
+//!
+//! Optional `metal_energy_compensation` restores a bounded share of rough metal
+//! reflectance in both path tracers. Omission or false keeps the previous BRDF.
+//!
+//! Caustics options may save `area_lights: true` and `environment: true` for
+//! both path tracers. Omission preserves the hard-source photon map.
+//!
+//! Caustics may also save `guided_emission: true` to concentrate photon emission
+//! around captured optical bounds with probability-corrected power. Omission or
+//! false preserves the original emission proposal. Older released readers warn
+//! about the newer format and retain fields they cannot interpret when saving.
+//!
+//! Caustics may save `refresh_per_pass: true` to build one photon map per camera
+//! pass. Omission or false retains one map per render job.
+//!
+//! Caustics may save `power_weighted_sources: true` to allocate photon launches
+//! using estimated source power with a uniform support component. Each source
+//! retains its matching probability correction. Omission or false preserves
+//! uniform source selection and the original random sequence.
+//!
+//! CPU jobs may save `environment_importance_sampling: true` to use the captured
+//! HDR radiance distribution for lighting and photon emission. Omission or false
+//! retains uniform sphere sampling. Older readers warn and retain unknown fields.

crates/doc/src/format/pending/render-quality-controls.rs

@@ -0,0 +1,4 @@
+//! Saves CPU worker selection, linear 2x supersampling and denoising controls in render setups.
+//! Older designs retain native-size output and the existing denoising settings; omitted
+//! CPU worker selection uses the bounded automatic pool, with one worker available for serial work.
+//! The last release warns about this newer design format and preserves fields it cannot read.

crates/doc/src/history_names.rs

@@ -571,9 +571,12 @@ pub(crate) fn matches(names: &Names, index: usize, name: &str) -> Option<Match>
     if descends(current, name) {
         return Some(Match::Piece);
     }
-    // The named piece, told apart by the faces around it: they still bound this piece.
+    // The named piece, told apart by the faces around it: they still bound this piece. Or the
+    // face it was a piece of, whole again since, which they still bound: the piece is all of it
+    // (#11731). Only a piece told apart by faces: a numbered one (`#2`, nothing told it apart)
+    // says nothing about which part of the whole face it was.
     if let Some((stem, around)) = crate::piece_names::piece_parts(name)
-        && crate::naming::parent_piece(current) == Some(stem)
+        && (crate::naming::parent_piece(current) == Some(stem) || (current == stem && !around.is_empty() && name.ends_with(']')))
         && info.is_some_and(|i| around.iter().all(|f| i.bounds.contains(*f)))
     {
         return Some(Match::Piece);

crates/doc/src/history_names_tests.rs

@@ -171,3 +171,21 @@ fn a_linked_designs_face_names_keep_their_pieces_and_nothing_else() {
         let _ = role(n);
     }
 }
+
+/// A face that was split when a name was stored and is whole again (#11731): the stored piece
+/// is all of it, when the face still touches the faces that told the piece apart.
+#[test]
+fn a_piece_name_finds_its_face_once_it_is_whole_again() {
+    let faces = named(&["top", "left", "right", "start"]);
+    let names = qualify(faces, &[(0, 1), (0, 3)]);
+    assert_eq!(names.faces[0], "top");
+    assert_eq!(matches(&names, 0, "top#[left]"), Some(Match::Piece));
+    assert_eq!(matches(&names, 0, "top#[left,start]"), Some(Match::Piece));
+    // It no longer touches a face the qualifier names: some other piece, gone since.
+    assert_eq!(matches(&names, 0, "top#[right]"), Some(Match::Stem));
+    assert_eq!(matches(&names, 0, "top#[left]@F9.1"), None, "a copy's piece");
+    // A numbered piece (nothing told it apart, or a tie) says nothing about which part it was.
+    assert_eq!(matches(&names, 0, "top#1"), Some(Match::Stem));
+    assert_eq!(matches(&names, 0, "top#[left]#2"), Some(Match::Stem));
+    assert_eq!(matches(&names, 0, "top#[]"), Some(Match::Stem));
+}

crates/doc/src/name_lookup.rs

@@ -339,6 +339,27 @@ pub fn locate_face(st: &ModelState, name: &str, p: Vec3) -> Option<FaceHit> {
     locate_in(st.bodies.iter().enumerate().filter(|(_, b)| !b.body.is_mesh()), name, p).ok()
 }
 
+/// The one body of `st` with a face the stored face name finds, as [`locate_face`] looks for it.
+/// `None` when no body has one, several do, or the name is one saved before format 14.
+pub(crate) fn face_body<'a>(st: &'a ModelState, name: &str) -> Option<&'a ModelBody> {
+    if let Some((body, _)) = crate::sheet::split_sheet_face_name(name) {
+        return st.bodies.iter().find(|b| b.name == body && !b.body.is_mesh());
+    }
+    if name.is_empty() || legacy_name(name).is_some() {
+        return None;
+    }
+    let solids = || st.bodies.iter().filter(|b| !b.body.is_mesh());
+    naming::warm_names(solids());
+    let mut holders = solids().filter(|b| {
+        let names = naming::names(b);
+        (0..names.faces.len()).any(|face| crate::history_names::matches(&names, face, name).is_some_and(exactly))
+    });
+    match (holders.next(), holders.next()) {
+        (Some(b), None) => Some(b),
+        _ => None,
+    }
+}
+
 /// [`locate_face`] for a feature that works on the faces of the body called `body` (a shell, a
 /// draft…): the face of that body the name finds, found without working out the names of every
 /// other body (a body named from geometry is meshed for it: seconds in a large model). When

crates/doc/src/named_projection_tests.rs

@@ -243,3 +243,57 @@ fn numbered_projection_refuses_a_pick_inside_a_hole_in_the_named_face() {
     assert_eq!(pick(5.).map(|(index, _)| index), Some(top));
     assert!(pick(0.).is_none(), "the pick is on the plane but inside the hole");
 }
+
+/// An edge picked when its side face was split in two keeps the piece in its name
+/// (`F2:side:l1#[F2:start]`); once the side is one face again the edge is still found (#11731).
+#[test]
+fn an_edge_named_by_a_piece_of_a_face_that_is_whole_again_is_found() {
+    let doc = Document {
+        features: serde_json::from_value(serde_json::json!([
+            {
+                "id": 1, "name": "Sketch1", "type": "sketch", "plane": {"name": "XY", "type": "origin"},
+                "sketch": {
+                    "points": [
+                        {"fixed": true, "id": "origin", "pos": [0., 0.]},
+                        {"fixed": false, "id": "p1", "pos": [0., 0.]},
+                        {"fixed": false, "id": "p2", "pos": [10., 0.]},
+                        {"fixed": false, "id": "p3", "pos": [10., 16.1]},
+                        {"fixed": false, "id": "p4", "pos": [0., 16.1]}
+                    ],
+                    "curves": [
+                        {"a": 1, "b": 2, "construction": false, "id": "l1", "type": "line"},
+                        {"a": 2, "b": 3, "construction": false, "id": "l2", "type": "line"},
+                        {"a": 3, "b": 4, "construction": false, "id": "l3", "type": "line"},
+                        {"a": 4, "b": 1, "construction": false, "id": "l4", "type": "line"}
+                    ],
+                    "constraints": [],
+                    "counters": {"k": 0, "l": 4, "p": 4}
+                }
+            },
+            {
+                "id": 2, "name": "Extrude1", "type": "extrude", "body_names": ["Body1"],
+                "extent": {"convention": "total_distance", "direction": "positive", "distance": "5"},
+                "operation": "new_body", "profiles": {"loops": [["l1", "l2", "l3", "l4"]], "type": "curves"}, "sketch": 1
+            }
+        ]))
+        .unwrap(),
+        ..Document::default()
+    };
+    let doc = crate::format::read(&doc.to_json()).unwrap();
+    let mut model = crate::Model::new();
+    model.evaluate(&doc);
+    let state = model.state();
+    let body = state.body("Body1").unwrap();
+    // The side along x = 0 meets the start cap in the edge under the pick.
+    let near = Vec3::new(0., 8.05, 0.);
+    let names = crate::naming::edge_names(body);
+    let whole = names.iter().find(|n| n.contains("F2:start") && n.contains("F2:side:l4")).expect("the side's edge on the start cap");
+    let piece = whole.replace("F2:side:l4", "F2:side:l4#[F2:start]");
+    let hit = crate::name_lookup::locate_edge(body, &piece, near).unwrap_or_else(|e| panic!("{piece}: {e}"));
+    assert!(hit.on_point, "the edge under the saved pick");
+    assert_eq!(hit.point, near);
+    assert_eq!(names.get(hit.edge), Some(whole));
+    // A piece told apart by a face the side never touches (the opposite side) is still refused.
+    let gone = whole.replace("F2:side:l4", "F2:side:l4#[F2:side:l2]");
+    assert!(crate::name_lookup::locate_edge(body, &gone, near).is_err(), "{gone}");
+}

crates/doc/src/placement_reuse.rs

@@ -240,8 +240,12 @@ fn same_feature(a: &Feature, b: &Feature) -> bool {
                 a == b
                     && meshes.len() == other.len()
                     && meshes.iter().zip(other).all(|(a, b)| {
-                        let crate::MeshData { name, positions, triangles, color } = a;
-                        *name == b.name && *color == b.color && Arc::ptr_eq(positions, &b.positions) && Arc::ptr_eq(triangles, &b.triangles)
+                        let crate::MeshData { name, positions, triangles, corner_normals, color } = a;
+                        *name == b.name
+                            && *color == b.color
+                            && Arc::ptr_eq(positions, &b.positions)
+                            && Arc::ptr_eq(triangles, &b.triangles)
+                            && Arc::ptr_eq(corner_normals, &b.corner_normals)
                     })
             }
             (

crates/doc/src/profile_refs.rs

@@ -120,6 +120,22 @@ pub fn profile_fallback_notes(ss: &SolvedSketch, selection: &ProfileSel) -> Vec<
     profile_selection_indices_lenient(ss, selection).map(|(_, notes)| notes).unwrap_or_default()
 }
 
+/// A curve that is a line, an arc or a circle, and not the output of a free-form offset.
+fn is_analytic(sketch: &solidcraft_sketch::Sketch, id: &str) -> bool {
+    sketch.curves.iter().any(|curve| {
+        curve.id == id
+            && matches!(
+                curve.kind,
+                solidcraft_sketch::CurveKind::Line { .. } | solidcraft_sketch::CurveKind::Arc { .. } | solidcraft_sketch::CurveKind::Circle { .. }
+            )
+    }) && !sketch.freeform_offsets.iter().any(|offset| offset.output == id)
+}
+
+/// A loop made only of analytic curves: how many pieces each is cut into does not matter.
+fn is_analytic_loop(sketch: &solidcraft_sketch::Sketch, curves: &[String]) -> bool {
+    !curves.is_empty() && curves.iter().all(|id| is_analytic(sketch, id))
+}
+
 fn quoted(ids: &[String]) -> String {
     ids.iter().map(|id| format!("`{id}`")).collect::<Vec<_>>().join(", ")
 }
@@ -135,17 +151,32 @@ fn quoted(ids: &[String]) -> String {
 ///    them; a tie goes to the one with the fewest curves the loop did not have, and a tie left
 ///    after that is not guessed.
 ///
-/// Loops of offset curves and legacy graph-span multisets (a curve listed once per piece) keep
-/// their exact meaning and never fall back.
+/// Analytic loops (lines, arcs and circles only) may list a curve more than once, as the pieces a
+/// circle was cut into when the loop was saved; the repeats are one curve here, since a sketch
+/// edit changes how many pieces a curve has but not the region it bounds. The outputs of an
+/// analytic offset (`sketch.offsets`) take step 1 only: their loop closes on its own or the pick
+/// is lost, a partial match by identifiers never stands for it. Loops with free-form offset
+/// outputs, free curves (splines, ellipses, conics) and legacy graph-span multisets keep their
+/// exact meaning and never fall back.
 fn fallback_loop(ss: &SolvedSketch, curves: &[String]) -> Option<(Vec<usize>, String)> {
+    let sketch = &ss.sketch;
+    let analytic_loop = is_analytic_loop(sketch, curves);
+    let deduped: Vec<String> = if analytic_loop {
+        let mut seen = BTreeSet::new();
+        curves.iter().filter(|id| seen.insert(id.as_str())).cloned().collect()
+    } else {
+        curves.to_vec()
+    };
+    let curves = deduped.as_slice();
     let stored: BTreeSet<&str> = curves.iter().map(String::as_str).collect();
     if stored.is_empty() || stored.len() != curves.len() || curves.len() > 512 || ss.profiles.len() > 10_000 {
         return None;
     }
-    let sketch = &ss.sketch;
-    let offset =
-        |id: &str| sketch.offsets.iter().any(|offset| offset.owns_output(id)) || sketch.freeform_offsets.iter().any(|offset| offset.output == id);
-    if stored.iter().any(|id| offset(id)) {
+    if stored.iter().any(|id| sketch.freeform_offsets.iter().any(|offset| offset.output == *id)) {
+        return None;
+    }
+    let from_offset = stored.iter().any(|id| sketch.offsets.iter().any(|offset| offset.owns_output(id)));
+    if from_offset && !analytic_loop {
         return None;
     }
     let drawn = |id: &str| sketch.curves.iter().any(|curve| curve.id == id && !curve.construction && !curve.centerline);
@@ -180,6 +211,9 @@ fn fallback_loop(ss: &SolvedSketch, curves: &[String]) -> Option<(Vec<usize>, St
             }
         }
     }
+    if from_offset {
+        return None;
+    }
     // 2. The closest loop by the curves it shares.
     let count = |profile: &solidcraft_sketch::Profile, inside: bool| {
         profile.outer_curves.iter().map(String::as_str).filter(|id| stored.contains(id) == inside).collect::<BTreeSet<_>>().len()
@@ -231,9 +265,12 @@ fn selection_indices(ss: &SolvedSketch, selection: &ProfileSel, mut notes: Optio
                     }
                     indices.push(unique_profile(ss, &ss.sketch.offset_boundary(id)?)?);
                 } else {
-                    // Repeated saved IDs identify exact graph spans. Their multiplicity
-                    // must not silently turn into a whole-source certificate on resize.
+                    // Repeated saved IDs of free curves identify exact graph spans. Their
+                    // multiplicity must not silently turn into a whole-source certificate on
+                    // resize. Lines, arcs and circles are exempt: how many pieces such a curve is
+                    // cut into changes with every line drawn across it (#9368).
                     if curves.iter().collect::<BTreeSet<_>>().len() != curves.len()
+                        && !is_analytic_loop(&ss.sketch, curves)
                         && !ss.profiles.iter().any(|profile| same_ids(curves, &profile.outer_curves))
                     {
                         return Err(crate::curve_pick_error(solidcraft_sketch::CurvePick::Missing, curves, &ss.name));

crates/doc/src/project.rs

@@ -912,7 +912,31 @@ pub fn refresh_face_anchor_links(
     sk: &mut Sketch,
     anchor: &crate::FaceAnchor,
 ) -> Result<Vec<String>> {
-    refresh_links_in(doc, vals, st, plane, sk, Some(anchor))
+    refresh_links_in(doc, vals, st, plane, sk, Some(anchor), LostNames::Fail)
+}
+
+/// What a link kept by the name of a face or edge does when the name finds nothing any more.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(crate) enum LostNames {
+    /// The sketch fails, asking for the reference to be picked again ([`DocError::Reselect`]).
+    Fail,
+    /// The link is marked lost and keeps its last geometry, with a warning naming the reference.
+    /// No other face or edge is taken for it. Only for showing a failed sketch while it is edited
+    /// (#12085), never for the evaluation the features after it build from.
+    Mark,
+}
+
+/// [`refresh_links`] (or [`refresh_face_anchor_links`] with `anchor`) that marks a link whose
+/// named face or edge is gone lost instead of failing ([`LostNames::Mark`]).
+pub(crate) fn refresh_links_marking_lost(
+    doc: &Document,
+    vals: &BTreeMap<String, Value>,
+    st: &ModelState,
+    plane: &Plane,
+    sk: &mut Sketch,
+    anchor: Option<&crate::FaceAnchor>,
+) -> Result<Vec<String>> {
+    refresh_links_in(doc, vals, st, plane, sk, anchor, LostNames::Mark)
 }
 
 /// Remove degree-two straight stations introduced by coplanar face subdivision.
@@ -989,7 +1013,7 @@ fn merge_family_lines(geom: Vec<LinkGeom>) -> Result<Vec<LinkGeom>> {
 /// longer finds exactly that face or edge is not lost: the sketch fails, asking for the
 /// reference to be picked again ([`DocError::Reselect`]).
 pub fn refresh_links(doc: &Document, vals: &BTreeMap<String, Value>, st: &ModelState, plane: &Plane, sk: &mut Sketch) -> Result<Vec<String>> {
-    refresh_links_in(doc, vals, st, plane, sk, None)
+    refresh_links_in(doc, vals, st, plane, sk, None, LostNames::Fail)
 }
 
 /// Lay every text that runs along a curve of its sketch along that curve as the solve left it.
@@ -1025,6 +1049,7 @@ fn refresh_links_in(
     plane: &Plane,
     sk: &mut Sketch,
     anchor: Option<&crate::FaceAnchor>,
+    lost_names: LostNames,
 ) -> Result<Vec<String>> {
     let mut warn = Vec::new();
     let links = sk.links.clone();
@@ -1034,16 +1059,17 @@ fn refresh_links_in(
         if !l.auto_face
             && let (Some(name), LinkSource::Face { body, at }) = (&l.face_name, &mut source)
         {
-            let (index, p) = st
-                .body(body)
-                .and_then(|target| {
-                    if l.kind == LinkKind::Project {
-                        crate::name_lookup::locate_projected_face(target, name, *at)
-                    } else {
-                        crate::naming::face_on_body(target, name, *at)
-                    }
-                })
-                .ok_or_else(|| DocError::reselect(name.as_str()))?;
+            let found = st.body(body).and_then(|target| {
+                if l.kind == LinkKind::Project {
+                    crate::name_lookup::locate_projected_face(target, name, *at)
+                } else {
+                    crate::naming::face_on_body(target, name, *at)
+                }
+            });
+            let Some((index, p)) = found else {
+                lose_named(sk, &l.id, name, lost_names, &mut warn)?;
+                continue;
+            };
             *at = p;
             named_face = Some((body.clone(), index, p));
         }
@@ -1051,7 +1077,10 @@ fn refresh_links_in(
         // edge has the name any more no other edge is taken for it: the sketch fails.
         let mut named_edge = None;
         if let (Some(name), LinkSource::Edge { body, at }) = (&l.edge_name, &source) {
-            let (body, hit) = locate_named_edge(st, body, name, *at).ok_or_else(|| DocError::reselect(name.as_str()))?;
+            let Some((body, hit)) = locate_named_edge(st, body, name, *at) else {
+                lose_named(sk, &l.id, name, lost_names, &mut warn)?;
+                continue;
+            };
             warn.extend(hit.note(name).map(|note| format!("projected {note}")));
             named_edge = Some((body, hit.edge, *at));
         }
@@ -1119,6 +1148,19 @@ fn refresh_links_in(
     Ok(warn)
 }
 
+/// A link whose face or edge `name` finds nothing: the sketch fails asking for it again, or (only
+/// while a failed sketch is shown for editing) the link is marked lost, with a warning naming it.
+fn lose_named(sk: &mut Sketch, id: &str, name: &str, lost_names: LostNames, warn: &mut Vec<String>) -> Result<()> {
+    match lost_names {
+        LostNames::Fail => Err(DocError::reselect(name)),
+        LostNames::Mark => {
+            sk.set_link_lost(id, true);
+            warn.push(format!("projected reference lost: `{name}` no longer exists as it was picked; reselect it"));
+            Ok(())
+        }
+    }
+}
+
 // ---------------------------------------------------------------------------------------------
 // Model lookups
 
@@ -1612,8 +1654,7 @@ pub(crate) fn section(plane: &Plane, m: &Mesh, face: Option<u32>) -> Vec<LinkGeo
     let size = m.bounds().diagonal().max(1e-9);
     let (segs, exact) = section_segments(plane, m, face);
     let segs: Vec<(Vec2, Vec2)> = segs.into_iter().map(|(a, b, _)| (a, b)).collect();
-    let loose = size * 2e-3;
-    let refine = |v: Vec<LinkGeom>| -> Vec<LinkGeom> { v.into_iter().map(|g| refine_round(g, &exact, loose)).collect() };
+    let refine = |v: Vec<LinkGeom>| -> Vec<LinkGeom> { refine_rounds(v, &exact, size) };
     let lossy = refine(fit_segments(&segs, size, false));
     // Lines and arcs that follow the section closely (the corners of a rounded profile stay
     // where they are) are kept when they take no more curves than the loose fit.
@@ -1627,7 +1668,57 @@ pub(crate) fn section(plane: &Plane, m: &Mesh, face: Option<u32>) -> Vec<LinkGeo
     let tight = size * 1e-4;
     let checkable = exact.len().saturating_mul(close.len()) <= 4_000_000;
     let strays = |v: &[LinkGeom]| exact.iter().any(|p| !v.iter().any(|g| plain_distance(g, *p).is_none_or(|d| d <= tight)));
-    if plain(&close) && (close.len() <= lossy.len() || (checkable && strays(&lossy) && !strays(&close))) { close } else { lossy }
+    let fitted = if plain(&close) && (close.len() <= lossy.len() || (checkable && strays(&lossy) && !strays(&close))) { close } else { lossy };
+    join_rounds(fitted, size * 1e-5)
+}
+
+/// Where the fit left a line and an arc ends apart by at most `tol`, both end at one point. A
+/// line can swallow an arc's first chord (a mesh crossing just past the tangent line), and
+/// [`refine_round`] moves an arc's ends but not the lines': the outline would not close.
+fn join_rounds(mut fitted: Vec<LinkGeom>, tol: f64) -> Vec<LinkGeom> {
+    for i in 0..fitted.len() {
+        let Some(&LinkGeom::Arc { c, mut a, mut b }) = fitted.get(i) else { continue };
+        let r = c.dist(a);
+        for end in [&mut a, &mut b] {
+            for curve in &mut fitted {
+                let LinkGeom::Line(p, q) = curve else { continue };
+                let (near, far) = if p.dist(*end) <= q.dist(*end) { (p, q) } else { (q, p) };
+                if near.dist(*end) <= tol {
+                    let joint = line_meets_round(*far, *near, c, r, tol);
+                    *near = joint;
+                    *end = joint;
+                }
+            }
+        }
+        if let Some(arc) = fitted.get_mut(i) {
+            *arc = LinkGeom::Arc { c, a, b };
+        }
+    }
+    fitted
+}
+
+/// Where a line from `far` ending near `near` meets the circle (`c`, `r`): the tangent point when
+/// the line runs into the circle there, within `tol` of it over the arc's first chord, else its
+/// crossing nearest `near`, else the circle's point nearest `near`.
+fn line_meets_round(far: Vec2, near: Vec2, c: Vec2, r: f64, tol: f64) -> Vec2 {
+    let nearest = |[x, y]: [Vec2; 2]| if x.dist(near) <= y.dist(near) { x } else { y };
+    let to_centre = c - far;
+    let span = to_centre.len();
+    if let Some(unit) = to_centre.normalized().filter(|_| span > r) {
+        let reach = (span * span - r * r).sqrt();
+        let (along, side) = (unit * (reach * reach / span), unit.perp() * (reach * r / span));
+        let tangent = nearest([far + along + side, far + along - side]);
+        if tangent.dist(near) <= tol + (2.0 * r * tol).sqrt() {
+            return tangent;
+        }
+    }
+    let Some(dir) = (near - far).normalized() else { return near };
+    let foot = far + dir * (c - far).dot(dir);
+    let half = r * r - (foot - c).len2();
+    if half >= 0.0 {
+        return nearest([foot + dir * half.sqrt(), foot - dir * half.sqrt()]);
+    }
+    (near - c).normalized().map_or(near, |unit| c + unit * r)
 }
 
 /// How far `p` lies from a line, arc or circle; None for any other curve.
@@ -1785,6 +1876,91 @@ fn section_segments(plane: &Plane, m: &Mesh, face: Option<u32>) -> (Vec<(Vec2, V
     (segs, exact.into_inner())
 }
 
+/// Re-fit each circle and arc of a fitted section through the exact section points near it.
+/// The outline stays closed: a line meeting an arc's end moves with it. Where two arcs meet,
+/// their refits stand only while their ends stay within the distance a profile joins ends
+/// across; else both keep their fits, since moving an arc's end would take it off its circle.
+fn refine_rounds(mut v: Vec<LinkGeom>, exact: &[Vec2], size: f64) -> Vec<LinkGeom> {
+    // Ends this close meet: the fit joins crossings this close into one point.
+    let meet = size * 1e-7;
+    let ends = |h: &LinkGeom| match *h {
+        LinkGeom::Arc { a, b, .. } => Some([a, b]),
+        _ => None,
+    };
+    let fitted = v.clone();
+    // Each arc's refit, and whether it stands.
+    let refits: Vec<Option<LinkGeom>> =
+        fitted.iter().map(|g| matches!(g, LinkGeom::Arc { .. }).then(|| refine_round(g.clone(), exact, size * 2e-3))).collect();
+    let mut stands: Vec<bool> = refits.iter().map(Option::is_some).collect();
+    // Where two arcs met as fitted: (arc, its end, other arc, its end).
+    let mut joints = Vec::new();
+    for (i, gi) in fitted.iter().enumerate() {
+        for (j, gj) in fitted.iter().enumerate().skip(i + 1) {
+            let (Some(ei), Some(ej)) = (ends(gi), ends(gj)) else { continue };
+            for (ki, pi) in ei.iter().enumerate() {
+                for (kj, pj) in ej.iter().enumerate() {
+                    if pi.dist(*pj) <= meet {
+                        joints.push((i, ki, j, kj));
+                    }
+                }
+            }
+        }
+    }
+    // Take back both refits at a joint they would tear, until no joint tears.
+    let end_now = |stands: &[bool], i: usize, k: usize| {
+        let g = if stands.get(i).copied().unwrap_or(false) { refits.get(i).and_then(Option::as_ref) } else { fitted.get(i) };
+        g.and_then(ends).and_then(|e| e.get(k).copied())
+    };
+    let mut changed = true;
+    while changed {
+        changed = false;
+        for &(i, ki, j, kj) in &joints {
+            let (Some(p), Some(q)) = (end_now(&stands, i, ki), end_now(&stands, j, kj)) else { continue };
+            if p.dist(q) > solidcraft_sketch::ENDPOINT_JOIN_TOL {
+                for k in [i, j] {
+                    if let Some(s) = stands.get_mut(k).filter(|s| **s) {
+                        *s = false;
+                        changed = true;
+                    }
+                }
+            }
+        }
+    }
+    for (i, g) in fitted.iter().enumerate() {
+        match g {
+            LinkGeom::Arc { a: a0, b: b0, .. } => {
+                let (true, Some(refined @ LinkGeom::Arc { a: a1, b: b1, .. })) =
+                    (stands.get(i).copied().unwrap_or(false), refits.get(i).and_then(Option::as_ref))
+                else {
+                    continue;
+                };
+                for h in v.iter_mut() {
+                    if let LinkGeom::Line(s, t) = h {
+                        for end in [s, t] {
+                            if end.dist(*a0) <= meet {
+                                *end = *a1;
+                            } else if end.dist(*b0) <= meet {
+                                *end = *b1;
+                            }
+                        }
+                    }
+                }
+                if let Some(slot) = v.get_mut(i) {
+                    *slot = refined.clone();
+                }
+            }
+            LinkGeom::Circle(..) => {
+                if let Some(slot) = v.get_mut(i) {
+                    *slot = refine_round(g.clone(), exact, size * 2e-3);
+                }
+            }
+            // Lines have moved with the arcs they meet; nothing else is refitted.
+            _ => {}
+        }
+    }
+    v
+}
+
 /// Re-fit a circle or arc through the exact section points near it, when there are enough.
 fn refine_round(g: LinkGeom, exact: &[Vec2], tol: f64) -> LinkGeom {
     let (c, r) = match g {

crates/doc/src/project_order.rs

@@ -368,6 +368,133 @@ mod tests {
         }
     }
 
+    #[test]
+    fn a_round_refitted_to_the_exact_section_still_meets_its_neighbours() {
+        use solidcore_record::Vec2;
+        use solidcraft_sketch::LinkGeom;
+        let v = Vec2::new;
+        // A 10 x 10 square with an R2 round at its top right corner, fitted from mesh crossings:
+        // the arc misses the round's circle (centre (8, 8)) by 5e-4 but meets the sides exactly.
+        // The exact crossings lie on the circle, and the refit puts the arc on it. The outline has
+        // to stay closed: a profile joins ends only within 1e-4, so a wider gap leaves none (the
+        // R2 rounds of a section at y = 20 through grooved walls, tangency-labs/solidcore#2908).
+        let c = v(7.9995, 7.9995);
+        let (p, q) = (v(10., c.y), v(c.x, 10.));
+        let exact: Vec<Vec2> =
+            (0..=8).map(|k| f64::from(k) * std::f64::consts::FRAC_PI_8 / 2.).map(|t| v(8. + 2. * t.cos(), 8. + 2. * t.sin())).collect();
+        let square = |top: Vec<LinkGeom>| {
+            let mut out = vec![LinkGeom::Line(v(0., 0.), v(10., 0.)), LinkGeom::Line(v(10., 0.), p), LinkGeom::Arc { c, a: p, b: q }];
+            out.extend(top);
+            out.push(LinkGeom::Line(v(0., 10.), v(0., 0.)));
+            out
+        };
+        // The top side a line, or an arc of radius 10 (a shallow round on it) and then a line.
+        let bulge = v(c.x, 20.);
+        let from = bulge + v(-(10f64.to_radians().sin()), -(10f64.to_radians().cos())) * 10.;
+        let cases =
+            [square(vec![LinkGeom::Line(q, v(0., 10.))]), square(vec![LinkGeom::Arc { c: bulge, a: from, b: q }, LinkGeom::Line(from, v(0., 10.))])];
+        // Ends as the sketch takes them: an arc ends on the circle through its start.
+        let ends = |g: &LinkGeom| match *g {
+            LinkGeom::Line(s, t) => vec![s, t],
+            LinkGeom::Arc { c, a, b } => vec![a, c + (b - c).normalized().unwrap_or(Vec2::X) * c.dist(a)],
+            _ => Vec::new(),
+        };
+        for (n, fitted) in cases.into_iter().enumerate() {
+            // The size of the section: the square's diagonal.
+            let out = super::super::refine_rounds(fitted, &exact, 200f64.sqrt());
+            for (i, g) in out.iter().enumerate() {
+                for e in ends(g) {
+                    let gap =
+                        out.iter().enumerate().filter(|(j, _)| *j != i).flat_map(|(_, h)| ends(h)).map(|x| x.dist(e)).fold(f64::INFINITY, f64::min);
+                    assert!(gap < 1e-9, "case {n}: gap {gap} at {e:?}: {out:?}");
+                }
+            }
+            // Where the round meets only lines, the arc lies on the round's circle.
+            if n == 0 {
+                let Some(LinkGeom::Arc { c, a, b }) = out.get(2) else { panic!("{out:?}") };
+                assert!(c.dist(v(8., 8.)) < 1e-9 && (c.dist(*a) - 2.).abs() < 1e-9 && (c.dist(*b) - 2.).abs() < 1e-9, "{out:?}");
+            }
+        }
+    }
+
+    #[test]
+    fn a_round_beside_another_arc_is_refitted_when_their_joint_stays_put() {
+        use solidcore_record::Vec2;
+        use solidcraft_sketch::LinkGeom;
+        let v = Vec2::new;
+        // The R2 round of a 10 x 10 square misses its circle (centre (8, 8)) by `s`, and an arc of
+        // radius 10 runs on from its end. The refit moves that joint by `s`. While that is within
+        // the 1e-4 a profile joins ends across, the round is refitted as before the fix for
+        // tangency-labs/solidcore#2908, and the profile still closes.
+        let exact: Vec<Vec2> =
+            (0..=8).map(|k| f64::from(k) * std::f64::consts::FRAC_PI_8 / 2.).map(|t| v(8. + 2. * t.cos(), 8. + 2. * t.sin())).collect();
+        for s in [1e-8, 1e-6, 1e-5, 5e-5, 9e-5] {
+            let c = v(8., 8. + s);
+            let (p, q) = (v(10., c.y), v(8., 10. + s));
+            let bulge = v(8., 20. + s);
+            let from = bulge + v(-(10f64.to_radians().sin()), -(10f64.to_radians().cos())) * 10.;
+            let fitted = vec![
+                LinkGeom::Line(v(0., 0.), v(10., 0.)),
+                LinkGeom::Line(v(10., 0.), p),
+                LinkGeom::Arc { c, a: p, b: q },
+                LinkGeom::Arc { c: bulge, a: from, b: q },
+                LinkGeom::Line(from, v(0., 10.)),
+                LinkGeom::Line(v(0., 10.), v(0., 0.)),
+            ];
+            let out = super::super::refine_rounds(fitted, &exact, 200f64.sqrt());
+            let (Some(LinkGeom::Arc { c, b, .. }), Some(LinkGeom::Arc { b: joint, .. })) = (out.get(2), out.get(3)) else { panic!("{out:?}") };
+            assert!(c.dist(v(8., 8.)) < 1e-12, "shift {s}: the round is refitted: {out:?}");
+            assert!(b.dist(*joint) < 1e-4, "shift {s}: {out:?}");
+        }
+    }
+
+    #[test]
+    fn two_arcs_refitted_the_same_way_keep_their_joint() {
+        use solidcore_record::Vec2;
+        use solidcraft_sketch::LinkGeom;
+        let v = Vec2::new;
+        // The R2 round of a 10 x 10 square and the arc of radius 10 running on from it both miss
+        // their circles (centres (8, 8) and (8, 20)) by `s` in the same direction. Both refits move
+        // their joint from (8, 10 + s) to (8, 10), so the two refitted arcs still meet, as they do
+        // before the fix for tangency-labs/solidcore#2908, even where `s` is past a profile's 1e-4.
+        let round = (0..=8).map(|k| f64::from(k) * std::f64::consts::FRAC_PI_8 / 2.).map(|t| v(8. + 2. * t.cos(), 8. + 2. * t.sin()));
+        let side = [261., 263., 265., 267., 269.].map(|d: f64| v(8. + 10. * d.to_radians().cos(), 20. + 10. * d.to_radians().sin()));
+        let exact: Vec<Vec2> = round.chain(side).collect();
+        for s in [1e-5, 2e-4, 5e-4] {
+            let c = v(8., 8. + s);
+            let (p, q) = (v(10., c.y), v(8., 10. + s));
+            let bulge = v(8., 20. + s);
+            let from = bulge + v(-(10f64.to_radians().sin()), -(10f64.to_radians().cos())) * 10.;
+            let fitted = vec![
+                LinkGeom::Line(v(0., 0.), v(10., 0.)),
+                LinkGeom::Line(v(10., 0.), p),
+                LinkGeom::Arc { c, a: p, b: q },
+                LinkGeom::Arc { c: bulge, a: from, b: q },
+                LinkGeom::Line(from, v(0., 10.)),
+                LinkGeom::Line(v(0., 10.), v(0., 0.)),
+            ];
+            let out = super::super::refine_rounds(fitted, &exact, 200f64.sqrt());
+            let (Some(LinkGeom::Arc { c: c1, b: b1, .. }), Some(LinkGeom::Arc { c: c2, b: b2, .. })) = (out.get(2), out.get(3)) else {
+                panic!("{out:?}")
+            };
+            assert!(c1.dist(v(8., 8.)) < 1e-9 && c2.dist(v(8., 20.)) < 1e-9, "shift {s}: both arcs are refitted: {out:?}");
+            assert!(b1.dist(*b2) < 1e-4, "shift {s}: {out:?}");
+            // The lines on the arcs' other ends move with them: the whole outline stays closed.
+            let ends = |g: &LinkGeom| match *g {
+                LinkGeom::Line(s, t) => vec![s, t],
+                LinkGeom::Arc { c, a, b } => vec![a, c + (b - c).normalized().unwrap_or(Vec2::X) * c.dist(a)],
+                _ => Vec::new(),
+            };
+            for (i, g) in out.iter().enumerate() {
+                for e in ends(g) {
+                    let gap =
+                        out.iter().enumerate().filter(|(j, _)| *j != i).flat_map(|(_, h)| ends(h)).map(|x| x.dist(e)).fold(f64::INFINITY, f64::min);
+                    assert!(gap < 1e-9, "shift {s}: gap {gap} at {e:?}: {out:?}");
+                }
+            }
+        }
+    }
+
     #[test]
     fn boundaries_touching_at_a_vertex_project() {
         // Two squares of one face family meet only at the corner (1, 1): four boundary edges meet

crates/doc/src/render_job.rs

@@ -6,8 +6,8 @@ use serde::{Deserialize, Serialize};
 use solidcraft_render::{
     Camera,
     job::{
-        CpuBudget, CpuProgressiveOptions, DirectionalLightOptions, JobOptions, LightingPreset, PunctualLightOptions, RaytraceEnvironmentOptions,
-        RaytraceOptions, RectangleLightOptions, StudioLighting, Sun, ThinLens, ToneMap,
+        CpuBudget, CpuProgressiveOptions, DenoiseSettings, DirectionalLightOptions, JobOptions, LightingPreset, PunctualLightOptions,
+        RaytraceEnvironmentOptions, RaytraceOptions, RectangleLightOptions, StudioLighting, Sun, ThinLens, ToneMap,
     },
     lighting::environment::SkyGradient,
 };
@@ -82,6 +82,18 @@ impl RenderJob {
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 #[serde(default, deny_unknown_fields)]
 pub struct CpuJob {
+    /// Zero selects a bounded native worker count; one retains serial transport.
+    #[serde(skip_serializing_if = "zero_threads")]
+    pub threads: u16,
+    /// Spend HDR lighting samples according to captured environment radiance.
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub environment_importance_sampling: bool,
+    /// Explicit ray-footprint mip and bounded anisotropic texture filtering.
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub texture_filtering: bool,
+    /// Approximate the missing microfacet bounces of rough isotropic conductors.
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub metal_energy_compensation: bool,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub caustics: Option<solidcraft_render::job::CausticOptions>,
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -98,6 +110,13 @@ pub struct CpuJob {
     pub path: Option<solidcraft_render::job::CpuPathOptions>,
     #[serde(skip_serializing_if = "std::ops::Not::not")]
     pub denoise: bool,
+    #[serde(skip_serializing_if = "DenoiseSettings::is_default")]
+    pub denoise_settings: DenoiseSettings,
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub denoise_diagnostics: bool,
+    /// Internal scale; saved width and height remain the exported image size.
+    #[serde(skip_serializing_if = "solidcraft_render::job::single_supersample")]
+    pub supersampling: u32,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub lens: Option<ThinLens>,
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -129,6 +148,10 @@ pub struct CpuJob {
 impl Default for CpuJob {
     fn default() -> Self {
         Self {
+            threads: 0,
+            environment_importance_sampling: false,
+            texture_filtering: false,
+            metal_energy_compensation: false,
             caustics: None,
             volume: None,
             sun: None,
@@ -136,6 +159,9 @@ impl Default for CpuJob {
             aging: Default::default(),
             adaptive: None,
             denoise: false,
+            denoise_settings: DenoiseSettings::default(),
+            denoise_diagnostics: false,
+            supersampling: 1,
             path: None,
             lens: None,
             output: None,
@@ -200,6 +226,10 @@ impl CpuJob {
             })
             .transpose()?;
         let options = RaytraceOptions {
+            threads: self.threads,
+            environment_importance_sampling: self.environment_importance_sampling,
+            texture_filtering: self.texture_filtering,
+            metal_energy_compensation: self.metal_energy_compensation,
             caustics: self.caustics,
             volume: self.volume,
             sun: self.sun.map(Box::new),
@@ -207,6 +237,9 @@ impl CpuJob {
             aging: (!aging.is_empty()).then(|| Box::new(aging)),
             adaptive: self.adaptive.map(Box::new),
             denoise: self.denoise,
+            denoise_settings: self.denoise_settings,
+            denoise_diagnostics: self.denoise_diagnostics,
+            supersampling: self.supersampling,
             path: self.path,
             lens: self.lens,
             output: self.output.clone(),
@@ -233,6 +266,12 @@ impl CpuJob {
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 #[serde(default, deny_unknown_fields)]
 pub struct GpuJob {
+    /// Explicit ray-footprint mip and bounded anisotropic texture filtering.
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub texture_filtering: bool,
+    /// Approximate the missing microfacet bounces of rough isotropic conductors.
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub metal_energy_compensation: bool,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub caustics: Option<solidcraft_render::job::CausticOptions>,
     #[serde(skip_serializing_if = "crate::render_aging::SavedAgingStack::is_empty")]
@@ -255,6 +294,13 @@ pub struct GpuJob {
     pub seed: u32,
     pub tone_map: ToneMap,
     pub denoise: bool,
+    #[serde(skip_serializing_if = "DenoiseSettings::is_default")]
+    pub denoise_settings: DenoiseSettings,
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    pub denoise_diagnostics: bool,
+    /// Internal scale; saved width and height remain the exported image size.
+    #[serde(skip_serializing_if = "solidcraft_render::job::single_supersample")]
+    pub supersampling: u32,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub lens: Option<ThinLens>,
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -269,6 +315,8 @@ impl Default for GpuJob {
     fn default() -> Self {
         let options = JobOptions::default();
         Self {
+            texture_filtering: false,
+            metal_energy_compensation: false,
             caustics: None,
             aging: Default::default(),
             nested_media: options.nested_media,
@@ -283,6 +331,9 @@ impl Default for GpuJob {
             seed: options.seed,
             tone_map: options.tone_map,
             denoise: options.denoise,
+            denoise_settings: options.denoise_settings,
+            denoise_diagnostics: options.denoise_diagnostics,
+            supersampling: options.supersampling,
             lens: options.lens,
             lighting: options.lighting,
             environment: None,
@@ -317,6 +368,8 @@ impl GpuJob {
             environment.validate()?;
         }
         let options = JobOptions {
+            texture_filtering: self.texture_filtering,
+            metal_energy_compensation: self.metal_energy_compensation,
             caustics: self.caustics,
             aging: self.aging.parameters_only()?,
             nested_media: self.nested_media,
@@ -331,6 +384,9 @@ impl GpuJob {
             seed: self.seed,
             tone_map: self.tone_map,
             denoise: self.denoise,
+            denoise_settings: self.denoise_settings,
+            denoise_diagnostics: self.denoise_diagnostics,
+            supersampling: self.supersampling,
             lens: self.lens,
             lighting: self.lighting,
             exposure_ev,
@@ -365,6 +421,10 @@ impl SkyEnvironment {
     }
 }
 
+fn zero_threads(threads: &u16) -> bool {
+    *threads == 0
+}
+
 fn unit() -> f64 {
     1.0
 }
@@ -478,3 +538,33 @@ mod cpu_volume_portable_tests {
         assert_eq!(serde_json::to_value(job).unwrap(), old);
     }
 }
+
+#[cfg(test)]
+#[test]
+fn portable_quality_controls_preserve_explicit_values_and_legacy_defaults() {
+    let old_cpu: CpuJob = serde_json::from_str("{}").unwrap();
+    let old_gpu: GpuJob = serde_json::from_str("{}").unwrap();
+    assert_eq!(old_cpu.threads, 0);
+    assert_eq!((old_cpu.supersampling, old_gpu.supersampling), (1, 1));
+    assert_eq!(old_cpu.denoise_settings, DenoiseSettings::default());
+    assert_eq!(old_gpu.denoise_settings, DenoiseSettings::default());
+    assert!(!old_cpu.denoise_diagnostics && !old_gpu.denoise_diagnostics);
+    let filter = DenoiseSettings { passes: 2, strength: 0.35, firefly_suppression: false };
+    let cpu = CpuJob { threads: 4, supersampling: 2, denoise: true, denoise_settings: filter, denoise_diagnostics: true, ..Default::default() };
+    let gpu = GpuJob { samples: 128, supersampling: 2, denoise: true, denoise_settings: filter, denoise_diagnostics: true, ..Default::default() };
+    let cpu_reopened: CpuJob = serde_json::from_value(serde_json::to_value(&cpu).unwrap()).unwrap();
+    let gpu_reopened: GpuJob = serde_json::from_value(serde_json::to_value(&gpu).unwrap()).unwrap();
+    assert_eq!(cpu_reopened, cpu);
+    assert_eq!(gpu_reopened, gpu);
+    let cpu_runtime = cpu_reopened.to_runtime(-1.0).unwrap();
+    let gpu_runtime = gpu_reopened.to_runtime(-1.0).unwrap();
+    assert_eq!((cpu_runtime.threads, cpu_runtime.supersampling), (4, 2));
+    assert_eq!((gpu_runtime.samples, gpu_runtime.supersampling), (128, 2));
+    assert_eq!(cpu_runtime.denoise_settings, filter);
+    assert_eq!(gpu_runtime.denoise_settings, filter);
+    assert!(cpu_runtime.denoise_diagnostics && gpu_runtime.denoise_diagnostics);
+    assert!(CpuJob { threads: 65, ..cpu.clone() }.validate(0.0).is_err());
+    assert!(GpuJob { supersampling: 3, ..gpu.clone() }.validate(0.0).is_err());
+    assert!(CpuJob { denoise_settings: DenoiseSettings { strength: f64::NAN, ..filter }, ..cpu }.validate(0.0).is_err());
+    assert!(GpuJob { denoise_settings: DenoiseSettings { passes: 4, ..filter }, ..gpu }.validate(0.0).is_err());
+}

crates/doc/src/render_optics.rs

@@ -147,8 +147,8 @@ impl OpticalBindings {
         self.0.iter()
     }
     pub fn validate(&self) -> Result<()> {
-        if self.0.len() > 32 || self.0.capacity() > 32 {
-            return Err(DocError::Invalid("at most 32 portable optical targets".into()));
+        if self.0.len() > solidcraft_render::job::MAX_OPTICAL_TARGETS || self.0.capacity() > solidcraft_render::job::MAX_OPTICAL_TARGETS {
+            return Err(DocError::Invalid("at most 128 portable optical targets".into()));
         }
         let mut seen = BTreeSet::new();
         for binding in &self.0 {
@@ -164,7 +164,7 @@ impl OpticalBindings {
     }
     pub fn validate_for_cpu_path(&self, path: bool) -> Result<()> {
         self.validate()?;
-        if self.len() > 8 {
+        if !path && self.len() > 8 {
             return Err(DocError::Invalid("CPU supports at most eight certified optical targets".into()));
         }
         for binding in self.iter() {
@@ -183,11 +183,11 @@ impl OpticalBindings {
             }
             *old = binding;
         } else {
-            if self.0.len() >= 32 {
-                return Err(DocError::Invalid("at most 32 portable optical targets".into()));
+            if self.0.len() >= solidcraft_render::job::MAX_OPTICAL_TARGETS {
+                return Err(DocError::Invalid("at most 128 portable optical targets".into()));
             }
             self.0.try_reserve_exact(1).map_err(|_| DocError::Invalid("optical binding reservation failed".into()))?;
-            if self.0.capacity() > 32 {
+            if self.0.capacity() > solidcraft_render::job::MAX_OPTICAL_TARGETS {
                 return Err(DocError::Invalid("optical capacity exceeds its bound".into()));
             }
             self.0.push(binding);
@@ -202,7 +202,7 @@ impl OpticalBindings {
 }
 impl<'de> Deserialize<'de> for OpticalBindings {
     fn deserialize<D: serde::Deserializer<'de>>(d: D) -> std::result::Result<Self, D::Error> {
-        let result = Self(bounded_sequence::<D, SavedOptics, 32>(d)?);
+        let result = Self(bounded_sequence::<D, SavedOptics, { solidcraft_render::job::MAX_OPTICAL_TARGETS }>(d)?);
         result.validate().map_err(serde::de::Error::custom)?;
         Ok(result)
     }
@@ -212,6 +212,25 @@ impl<'de> Deserialize<'de> for OpticalBindings {
 mod advanced_model_contract_tests {
     use super::*;
     use solidcraft_render::glass_model::{Dispersion, GlassModel, ThinFilm};
+    #[test]
+    fn portable_optics_keep_128_targets_and_legacy_cpu_keeps_its_explicit_limit() {
+        let mut bindings = OpticalBindings::default();
+        for feature in 1..=solidcraft_render::job::MAX_OPTICAL_TARGETS {
+            let binding = SavedOptics {
+                target: RenderBodyTarget { definition: "OPUS".into(), feature: feature as u64, component: 0, occurrence_path: Vec::new() },
+                optics: OpticalMaterial::default(),
+            };
+            bindings.set(binding, false).unwrap();
+        }
+        bindings.validate_for_cpu_path(true).unwrap();
+        assert!(bindings.validate_for_cpu().is_err());
+        let raw = serde_json::to_value(&bindings).unwrap();
+        assert_eq!(serde_json::from_value::<OpticalBindings>(raw.clone()).unwrap(), bindings);
+        let mut too_many = raw.as_array().unwrap().clone();
+        too_many.push(too_many[0].clone());
+        assert!(serde_json::from_value::<OpticalBindings>(serde_json::Value::Array(too_many)).is_err());
+    }
+
     #[test]
     fn advanced_optics_keep_every_authored_number_through_saved_and_cpu_lowering() {
         let model = GlassModel {
@@ -238,14 +257,32 @@ mod advanced_model_contract_tests {
     #[test]
     fn caustic_quality_is_portable_between_both_saved_jobs_and_runtime_requests() {
         use crate::render_job::{CpuJob, GpuJob};
-        let caustics = Some(solidcraft_render::job::CausticOptions { photons: 8192, radius_mm: 0.4, max_depth: 12, seed: 381 });
-        let cpu = CpuJob { caustics, path: Some(Default::default()), progressive: Some(Default::default()), ..Default::default() };
+        let caustics = Some(solidcraft_render::job::CausticOptions {
+            photons: 8192,
+            radius_mm: 0.4,
+            max_depth: 12,
+            seed: 381,
+            area_lights: false,
+            environment: false,
+            guided_emission: true,
+            refresh_per_pass: true,
+            power_weighted_sources: true,
+        });
+        let cpu = CpuJob {
+            caustics,
+            environment_importance_sampling: true,
+            path: Some(Default::default()),
+            progressive: Some(Default::default()),
+            ..Default::default()
+        };
         let gpu = GpuJob { caustics, ..Default::default() };
         assert_eq!(cpu.to_runtime(0.0).unwrap().caustics, caustics);
+        assert!(cpu.to_runtime(0.0).unwrap().environment_importance_sampling);
         assert_eq!(gpu.to_runtime(0.0).unwrap().caustics, caustics);
         assert_eq!(serde_json::from_value::<CpuJob>(serde_json::to_value(&cpu).unwrap()).unwrap(), cpu);
         assert_eq!(serde_json::from_value::<GpuJob>(serde_json::to_value(&gpu).unwrap()).unwrap(), gpu);
         assert!(serde_json::to_value(CpuJob::default()).unwrap().get("caustics").is_none());
+        assert!(serde_json::to_value(CpuJob::default()).unwrap().get("environment_importance_sampling").is_none());
         assert!(serde_json::to_value(GpuJob::default()).unwrap().get("caustics").is_none());
     }
 }

crates/doc/src/render_settings.rs

@@ -212,15 +212,27 @@ impl RenderSetup {
                 ));
             }
             job.validate(&self.camera, self.exposure_ev)?;
+            if let RenderJob::GpuPath { options, .. } = job {
+                solidcraft_render::job::supersampled_dimensions(self.width, self.height, options.supersampling)
+                    .map_err(|e| DocError::Invalid(e.to_string()))?;
+            }
             if let RenderJob::CpuRaytrace { options, .. } = job {
-                if options.denoise {
-                    solidcraft_render::job::validate_cpu_denoise_image(self.width, self.height).map_err(|e| DocError::Invalid(e.to_string()))?;
+                // Existing native-size Workstation intent remains readable. X2
+                // uses the bounded 8K output envelope and pays for its internal grid.
+                let (trace_width, trace_height) = if options.supersampling == 1 && !options.denoise && !options.denoise_diagnostics {
+                    (self.width, self.height)
+                } else {
+                    solidcraft_render::job::supersampled_dimensions(self.width, self.height, options.supersampling)
+                        .map_err(|e| DocError::Invalid(e.to_string()))?
+                };
+                if options.denoise || options.denoise_diagnostics {
+                    solidcraft_render::job::validate_cpu_denoise_image(trace_width, trace_height).map_err(|e| DocError::Invalid(e.to_string()))?;
                 }
                 options
                     .budget
                     .validate_image(
-                        self.width,
-                        self.height,
+                        trace_width,
+                        trace_height,
                         solidcraft_render::job::cpu_camera_sampling(options.progressive, options.adaptive, options.budget)
                             .map_err(|e| DocError::Invalid(e.to_string()))?,
                     )
@@ -670,7 +682,7 @@ mod tests {
         gpu(3840, 2160).validate().unwrap();
         gpu(3840, 2160).validate_for_gpu().unwrap();
         let message = gpu(8193, 8193).validate().unwrap_err().to_string();
-        assert!(message.contains("(8192 pixels per side, 16777216 pixels in all)"), "{message}");
+        assert!(message.contains("(8192 pixels per side, 33554432 pixels in all)"), "{message}");
         assert!(!message.contains("CPU resource profile"), "{message}");
     }
 
@@ -883,7 +895,7 @@ mod tests {
             json!({"job":{"method":"gpu_path","options":{"environment":{"kind":"hdr","path":"not-portable.hdr"}}}}),
             json!({"job":{"method":"gpu_path","options":{"exposure_ev":0}}}),
             json!({"job":{"method":"gpu_path","options":{"samples":0}}}),
-            json!({"job":{"method":"gpu_path","options":{"max_depth":17}}}),
+            json!({"job":{"method":"gpu_path","options":{"max_depth":65}}}),
             json!({"job":{"method":"gpu_path","options":{"environment":{"kind":"sky","intensity":101}}}}),
             json!({"job":{"method":"gpu_path","options":{"lighting":{"environment":[-1,0,0]}}}}),
             json!({"camera":Camera { fov: 0.0, ..Default::default() },"job":{"method":"gpu_path","options":{"lens":{"aperture_radius_mm":1,"focus_distance_mm":10}}}}),
@@ -1021,7 +1033,7 @@ mod cpu_budget_tests {
         let old = CpuJob::default();
         assert!(old.path.is_none());
         assert!(serde_json::to_value(&old).unwrap().get("path").is_none());
-        for depth in [1, 8, 16] {
+        for depth in [1, 8, 16, 64] {
             let setup:RenderSetup=serde_json::from_value(json!({"width":8,"height":8,"job":{"method":"cpu_raytrace","options":{"path":{"max_depth":depth},"progressive":{"samples_per_pixel":7,"seed":9}}}})).unwrap();
             setup.validate().unwrap();
             let mut document = crate::Document::default();
@@ -1032,7 +1044,7 @@ mod cpu_budget_tests {
         }
         for raw in [
             json!({"path":{"max_depth":0},"progressive":{"samples_per_pixel":7,"seed":9}}),
-            json!({"path":{"max_depth":17},"progressive":{"samples_per_pixel":7,"seed":9}}),
+            json!({"path":{"max_depth":65},"progressive":{"samples_per_pixel":7,"seed":9}}),
             json!({"path":{"max_depth":8}}),
             json!({"path":{"max_depth":8},"progressive":{"samples_per_pixel":7,"seed":9},"shadows":false}),
         ] {
@@ -1073,7 +1085,7 @@ fn cpu_denoise_saved_flag_roundtrips_offline_and_keeps_false_omitted() {
     setup.validate().unwrap();
     let Some(RenderJob::CpuRaytrace { options, .. }) = &mut setup.job else { panic!("CPU job expected") };
     options.denoise = true;
-    assert!(setup.validate().unwrap_err().to_string().contains("CPU denoising"));
+    assert_eq!(setup.validate().unwrap_err(), DocError::Invalid("LimitExceeded: output requires 1..8192 sides and at most 33554432 pixels".into()),);
 }
 
 #[cfg(test)]
@@ -1220,7 +1232,9 @@ mod cpu_adaptive_saved_tests {
             serde_json::from_value::<RenderSetup>(cap).unwrap().validate().is_err(),
             "16 pilots cannot be hidden outside Compact's 64-sample cap"
         );
-        for (budget, maximum) in [(CpuBudget::Compact, 64), (CpuBudget::Studio, 1024), (CpuBudget::Workstation, 4096)] {
+        for (budget, maximum) in
+            [(CpuBudget::Compact, 64), (CpuBudget::Studio, 1024), (CpuBudget::Workstation, solidcraft_render::job::MAX_CPU_SAMPLES_PER_PIXEL)]
+        {
             let mut runtime = runtime.clone();
             runtime.budget = budget;
             runtime.progressive = Some(CpuProgressiveOptions { samples_per_pixel: maximum - 16, seed: 81 });
@@ -1385,3 +1399,39 @@ mod cpu_celestial_saved_tests {
         assert!(defaults.get("sun").is_none() && defaults.get("sky").is_none());
     }
 }
+
+#[test]
+fn render_quality_saved_intent_preserves_output_size_and_validates_the_internal_grid() {
+    let gpu: RenderSetup = serde_json::from_value(serde_json::json!({
+        "width":7680,"height":4320,"job":{"method":"gpu_path","options":{
+            "samples":128,"supersampling":2,"denoise":true,"denoise_diagnostics":true,
+            "denoise_settings":{"passes":2,"strength":0.5,"firefly_suppression":false}
+        }}
+    }))
+    .unwrap();
+    gpu.validate().unwrap();
+    let reopened: RenderSetup = serde_json::from_value(serde_json::to_value(&gpu).unwrap()).unwrap();
+    assert_eq!(reopened, gpu);
+    assert_eq!((reopened.width, reopened.height), (7680, 4320));
+    let mut cpu: RenderSetup = serde_json::from_value(serde_json::json!({
+        "width":7680,"height":4320,"job":{"method":"cpu_raytrace","options":{
+            "threads":4,"budget":"workstation","progressive":{"samples_per_pixel":128},"supersampling":2
+        }}
+    }))
+    .unwrap();
+    cpu.validate().unwrap();
+    assert_eq!((cpu.width, cpu.height), (7680, 4320));
+    cpu.width = 1024;
+    cpu.height = 1024;
+    let Some(RenderJob::CpuRaytrace { options, .. }) = &mut cpu.job else { panic!("expected CPU job") };
+    options.budget = solidcraft_render::job::CpuBudget::Compact;
+    options.progressive.as_mut().unwrap().samples_per_pixel = 8;
+    assert!(cpu.validate().is_err(), "X2 must charge four million internal pixels to Compact's progressive limit");
+    let Some(RenderJob::CpuRaytrace { options, .. }) = &mut cpu.job else { panic!("expected CPU job") };
+    options.supersampling = 1;
+    cpu.validate().unwrap();
+    let mut invalid = gpu;
+    invalid.width = 8193;
+    invalid.height = 1;
+    assert!(invalid.validate().is_err());
+}

crates/doc/src/render_texture_resources.rs

@@ -465,7 +465,17 @@ mod tests {
         let doc = crate::Document { render: Arc::new(settings.clone()), ..Default::default() };
         let wire = doc.to_json();
         assert_eq!(crate::Document::from_json(&wire).unwrap(), doc);
-        assert!(wire.contains("embedded-surface-textures"));
+        // The saved design holds the texture's bytes under the resource's own key.
+        fn resource_saved(v: &serde_json::Value, key: &str) -> bool {
+            match v {
+                serde_json::Value::Object(map) => {
+                    map.get("texture_resources").and_then(|t| t.get(key)).is_some() || map.values().any(|v| resource_saved(v, key))
+                }
+                serde_json::Value::Array(items) => items.iter().any(|v| resource_saved(v, key)),
+                _ => false,
+            }
+        }
+        assert!(resource_saved(&serde_json::from_str(&wire).unwrap(), &id.to_string()));
         assert!(!wire.contains("builtin://"));
         assert!(!wire.contains("file://"));
         settings.texture_resources.remove(&id);

crates/doc/src/tests.rs

@@ -871,6 +871,86 @@ fn a_join_keeps_blocks_apart_in_one_body() {
     assert_eq!(kept, None);
 }
 
+/// A body of two pieces joined apart, split by a plane through both pieces: the split gives the
+/// halves of every piece, not the halves of one of them (#6738).
+#[test]
+fn a_split_of_a_body_of_two_pieces_gives_the_halves_of_both() {
+    let mut doc = Document::new("split two pieces");
+    // One sketch, two squares 20 mm across and 30 mm apart.
+    let mut sk = Sketch::new();
+    let mut corners = Vec::new();
+    for x in [0.0, 50.0] {
+        let p: Vec<usize> = [Vec2::new(x, 10.0), Vec2::new(x + 20.0, 10.0), Vec2::new(x + 20.0, 30.0), Vec2::new(x, 30.0)]
+            .iter()
+            .map(|c| sk.add_point(*c, None).unwrap())
+            .collect();
+        for i in 0..4 {
+            sk.add_line_pts(p[i], p[(i + 1) % 4], None).unwrap();
+        }
+        corners.extend(p);
+    }
+    for p in corners {
+        sk.add_constraint(ConstraintKind::Fix { p }, None).unwrap();
+    }
+    let s = doc.add_feature(FeatureKind::Sketch { plane: PlaneRef::Origin { name: "XY".into() }, sketch: sk }, None).unwrap();
+    doc.add_feature(
+        FeatureKind::Extrude {
+            thin: None,
+            sketch: crate::SketchId(s),
+            profiles: ProfileSel::All,
+            extent: Extent {
+                convention: crate::ExtrudeConvention::LegacyPerSide,
+                distance: "10".into(),
+                direction: Direction::Positive,
+                distance2: None,
+                start_offset: None,
+                through_all: false,
+                second_follows_first: false,
+                taper: None,
+                corner: Default::default(),
+                to: None,
+                to_offset: None,
+                from: None,
+                to_body_apart: false,
+            },
+            operation: Operation::NewBody,
+            targets: vec![],
+        },
+        None,
+    )
+    .unwrap();
+    doc.add_feature(
+        FeatureKind::Combine { target: "Body1".into(), tools: vec!["Body2".into()], operation: Operation::Join, keep_tools: false },
+        None,
+    )
+    .unwrap();
+    // A plane through the middle of both squares (the extrusion is 10 mm tall).
+    let split = doc
+        .add_feature(
+            FeatureKind::Split {
+                body: "Body1".into(),
+                plane: PlaneRef::Offset { base: Box::new(PlaneRef::Origin { name: "XY".into() }), distance: "5".into() },
+                tool: None,
+                sketch: None,
+                line: None,
+            },
+            None,
+        )
+        .unwrap();
+    let mut m = Model::new();
+    m.evaluate(&doc);
+    let error = m.result(split).unwrap().error.clone();
+    assert!(error.is_none(), "the split of a body of two pieces: {error:?}");
+    let bodies: Vec<(String, f64, usize)> =
+        m.state().bodies.iter().map(|b| (b.name.clone(), measure(&b.body).unwrap().volume, b.body.lumps().unwrap().len())).collect();
+    assert_eq!(bodies.len(), 2, "{bodies:?}");
+    for (name, volume, lumps) in &bodies {
+        // Each half holds the half of both squares: two pieces, half the body each.
+        assert!(rel(*volume, 4000.0) < 1e-6, "{name}: {bodies:?}");
+        assert_eq!(*lumps, 2, "{name}: {bodies:?}");
+    }
+}
+
 /// A square ring joined with an arm touching its outer corner along an edge and a hub apart in
 /// its hole: the ring and the hub stay one body under the ring's name, the arm is split off, and
 /// the join says it touched along an edge.

crates/dynamics/src/integrate.rs

@@ -6,9 +6,9 @@ use crate::model::{Integrator, MAX_MAGNITUDE, MAX_STEPS, Model, Settings};
 use crate::system::System;
 use crate::{DynamicsError, Result, Sample, Stats, Trajectory};
 
-/// Dormand–Prince 5(4) tableau (the system is autonomous, so the nodes are not needed): stage
-/// weights, fifth-order weights and the difference between the fifth- and fourth-order weights
-/// (the error estimate).
+/// Dormand–Prince 5(4) tableau: nodes, stage weights, fifth-order weights and the difference
+/// between the fifth- and fourth-order weights (the error estimate).
+const DP_C: [f64; 7] = [0.0, 1.0 / 5.0, 3.0 / 10.0, 4.0 / 5.0, 8.0 / 9.0, 1.0, 1.0];
 const DP_A: [[f64; 6]; 7] = [
     [0.0; 6],
     [1.0 / 5.0, 0.0, 0.0, 0.0, 0.0, 0.0],
@@ -58,17 +58,18 @@ struct Run<'a> {
 }
 
 impl Run<'_> {
-    fn deriv(&self, y: &[f64]) -> Result<Vec<f64>> {
-        self.sys.accelerations(y).map(|a| a.ydot)
+    fn deriv(&self, t: f64, y: &[f64]) -> Result<Vec<f64>> {
+        self.sys.accelerations(t, y).map(|a| a.ydot)
     }
 
     /// Normalise, project and check a new state.
     fn finish_step(&mut self, y: &mut [f64], t: f64) -> Result<()> {
         self.sys.normalize(y).map_err(|e| at_time(e, t))?;
         if self.settings.projection {
-            self.sys.project_positions(y, self.settings.projection_tol).map_err(|e| at_time(e, t))?;
-            self.sys.project_velocities(y).map_err(|e| at_time(e, t))?;
+            self.sys.project_positions(t, y, self.settings.projection_tol).map_err(|e| at_time(e, t))?;
+            self.sys.project_velocities(t, y).map_err(|e| at_time(e, t))?;
         }
+        self.sys.resync(y);
         if !y.iter().all(|x| x.is_finite() && x.abs() < MAX_MAGNITUDE) {
             return Err(DynamicsError::Diverged { time: t });
         }
@@ -82,23 +83,23 @@ impl Run<'_> {
         Ok(())
     }
 
-    fn rk4(&mut self, y: &[f64], h: f64) -> Result<Vec<f64>> {
-        let k1 = self.deriv(y)?;
-        let k2 = self.deriv(&combine(y, std::slice::from_ref(&k1), &[0.5], h))?;
-        let k3 = self.deriv(&combine(y, std::slice::from_ref(&k2), &[0.5], h))?;
-        let k4 = self.deriv(&combine(y, std::slice::from_ref(&k3), &[1.0], h))?;
+    fn rk4(&mut self, t: f64, y: &[f64], h: f64) -> Result<Vec<f64>> {
+        let k1 = self.deriv(t, y)?;
+        let k2 = self.deriv(t + 0.5 * h, &combine(y, std::slice::from_ref(&k1), &[0.5], h))?;
+        let k3 = self.deriv(t + 0.5 * h, &combine(y, std::slice::from_ref(&k2), &[0.5], h))?;
+        let k4 = self.deriv(t + h, &combine(y, std::slice::from_ref(&k3), &[1.0], h))?;
         Ok(combine(y, &[k1, k2, k3, k4], &[1.0 / 6.0, 1.0 / 3.0, 1.0 / 3.0, 1.0 / 6.0], h))
     }
 
     /// One Dormand–Prince step: the fifth-order state and the scaled error norm.
-    fn dopri(&mut self, y: &[f64], h: f64, rel_tol: f64, abs_tol: f64) -> Result<(Vec<f64>, f64)> {
+    fn dopri(&mut self, t: f64, y: &[f64], h: f64, rel_tol: f64, abs_tol: f64) -> Result<(Vec<f64>, f64)> {
         let mut ks: Vec<Vec<f64>> = Vec::with_capacity(7);
-        for a in DP_A.iter().take(6) {
+        for (a, c) in DP_A.iter().zip(DP_C).take(6) {
             let stage = combine(y, &ks, a, h);
-            ks.push(self.deriv(&stage)?);
+            ks.push(self.deriv(t + c * h, &stage)?);
         }
         let y5 = combine(y, &ks, &DP_B, h);
-        ks.push(self.deriv(&y5)?);
+        ks.push(self.deriv(t + h, &y5)?);
         let err = combine(&vec![0.0; y.len()], &ks, &DP_E, h);
         let n = y.len().max(1) as f64;
         let sum: f64 = err
@@ -123,7 +124,7 @@ impl Run<'_> {
                 let h = span / n;
                 for _ in 0..n as usize {
                     self.count_step(*t)?;
-                    let mut next = self.rk4(y, h).map_err(|e| at_time(e, *t))?;
+                    let mut next = self.rk4(*t, y, h).map_err(|e| at_time(e, *t))?;
                     *t += h;
                     self.finish_step(&mut next, *t)?;
                     *y = next;
@@ -136,7 +137,7 @@ impl Run<'_> {
                     self.count_step(*t)?;
                     let remaining = t_end - *t;
                     let h = h_next.clamp(min_step, max_step).min(remaining);
-                    let (mut next, err) = self.dopri(y, h, rel_tol, abs_tol).map_err(|e| at_time(e, *t))?;
+                    let (mut next, err) = self.dopri(*t, y, h, rel_tol, abs_tol).map_err(|e| at_time(e, *t))?;
                     // The usual controller: 0.9·err^(−1/5), within [0.2, 5].
                     let factor = if err > 0.0 { (0.9 * err.powf(-0.2)).clamp(0.2, 5.0) } else { 5.0 };
                     if err <= 1.0 {
@@ -164,11 +165,18 @@ impl Run<'_> {
     }
 
     fn sample(&mut self, y: &[f64], t: f64) -> Result<Sample> {
-        let acc = self.sys.accelerations(y).map_err(|e| at_time(e, t))?;
-        let constraint_error = self.sys.constraint_error(y);
+        let acc = self.sys.accelerations(t, y).map_err(|e| at_time(e, t))?;
+        let constraint_error = self.sys.constraint_error(t, y);
         self.stats.max_constraint_error = self.stats.max_constraint_error.max(constraint_error);
         self.stats.redundant_equations = self.stats.redundant_equations.max(acc.row_count().saturating_sub(acc.rank));
-        Ok(Sample { time: t, bodies: self.sys.body_states(y), joints: self.sys.joint_results(y, &acc), energy: self.sys.energy(y), constraint_error })
+        Ok(Sample {
+            time: t,
+            bodies: self.sys.body_states(y),
+            joints: self.sys.joint_results(y, &acc),
+            drives: self.sys.drive_efforts(&acc),
+            energy: self.sys.energy(y),
+            constraint_error,
+        })
     }
 }
 
@@ -177,11 +185,12 @@ impl Run<'_> {
 pub fn simulate(model: &Model, settings: &Settings) -> Result<Trajectory> {
     settings.validate()?;
     let sys = System::new(model, settings.baumgarte)?;
-    let mut y = System::initial_state(model)?;
-    // An inconsistent start (frames a little apart, velocities the joints don't allow) is
-    // brought onto the joints first, whether or not later steps project.
-    sys.project_positions(&mut y, settings.projection_tol).map_err(|e| at_time(e, 0.0))?;
-    sys.project_velocities(&mut y).map_err(|e| at_time(e, 0.0))?;
+    let mut y = sys.initial_state(model)?;
+    // An inconsistent start (frames a little apart, velocities the joints don't allow, drives
+    // starting elsewhere) is brought onto the joints first, whether or not later steps project.
+    sys.project_positions(0.0, &mut y, settings.projection_tol).map_err(|e| at_time(e, 0.0))?;
+    sys.project_velocities(0.0, &mut y).map_err(|e| at_time(e, 0.0))?;
+    sys.resync(&mut y);
     let mut run = Run { sys: &sys, settings, stats: Stats::default() };
     let count = (settings.duration / settings.output_interval).ceil() as usize;
     let mut samples = Vec::with_capacity(count + 1);

crates/dynamics/src/lib.rs

@@ -3,7 +3,9 @@
 //!
 //! The crate knows nothing of documents or occurrences: a [`Model`] lists bodies (mass,
 //! inertia about the centre of mass, starting pose and velocities), joints between frames on
-//! them ([`JointKind`]: rigid, revolute, slider, cylindrical, planar, ball) and force elements;
+//! them ([`JointKind`]: rigid, revolute, slider, cylindrical, planar, ball), force elements
+//! (point and joint spring-dampers, motors along joint values, loads), drives that make a joint
+//! value follow a [`Profile`] in time, and motion links (gears, racks, screws) between values;
 //! [`simulate`] returns a [`Trajectory`] of poses, joint values and rates, joint reactions and
 //! energies at a fixed output interval. The assembly layer maps occurrences and joints to it.
 //!
@@ -31,8 +33,8 @@ use solidcore_record::Vec3;
 pub use integrate::simulate;
 pub use math::{Mat3, Quat};
 pub use model::{
-    Anchor, Body, Force, Integrator, Joint, JointKind, MAX_BODIES, MAX_CONSTRAINT_ROWS, MAX_FORCES, MAX_JOINTS, MAX_MAGNITUDE,
-    MAX_PROJECTION_ITERATIONS, MAX_SAMPLES, MAX_STEPS, Marker, Model, STANDARD_GRAVITY, Settings,
+    Anchor, Body, Coord, Drive, Force, Integrator, Joint, JointKind, Link, MAX_BODIES, MAX_CONSTRAINT_ROWS, MAX_FORCES, MAX_JOINTS, MAX_MAGNITUDE,
+    MAX_PROFILE_POINTS, MAX_PROJECTION_ITERATIONS, MAX_SAMPLES, MAX_STEPS, Marker, Model, Profile, STANDARD_GRAVITY, Settings,
 };
 
 /// Why a simulation could not run or stopped.
@@ -90,14 +92,25 @@ pub struct Energy {
     pub kinetic: f64,
     /// Potential energy of gravity, zero at the world origin.
     pub gravity: f64,
-    /// Energy stored in springs (preload included).
+    /// Energy stored in springs, point and joint ones (preload included).
     pub spring: f64,
+    /// Work put in since the start by motors, drives and loads.
+    #[serde(default)]
+    pub input: f64,
+    /// Energy taken out since the start by dampers.
+    #[serde(default)]
+    pub dissipated: f64,
 }
 
 impl Energy {
+    /// Kinetic plus potential energy.
     pub fn total(&self) -> f64 {
         self.kinetic + self.gravity + self.spring
     }
+    /// `total + dissipated − input`: constant along a run up to the integration error.
+    pub fn balance(&self) -> f64 {
+        self.total() + self.dissipated - self.input
+    }
 }
 
 /// The system at one output time.
@@ -107,8 +120,12 @@ pub struct Sample {
     pub time: f64,
     pub bodies: Vec<BodyState>,
     pub joints: Vec<JointResult>,
+    /// What each drive applies along its joint value to make it follow (mN·mm for an angle, mN
+    /// for a distance), in [`Model::drives`] order.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub drives: Vec<f64>,
     pub energy: Energy,
-    /// The largest joint equation error (mm for points; directions are unitless).
+    /// The largest constraint equation error (mm for points; directions are unitless).
     pub constraint_error: f64,
 }
 

crates/dynamics/src/model.rs

@@ -141,10 +141,172 @@ pub struct Joint {
     pub b: Marker,
 }
 
-/// A force element.
+/// One value of a joint: `dof` indexes [`JointKind::values`]. Revolute, slider, cylindrical
+/// and planar joints have values that springs, motors, drives and links can act on; ball and
+/// rigid joints have none.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Coord {
+    pub joint: usize,
+    #[serde(default)]
+    pub dof: usize,
+}
+
+impl Coord {
+    pub fn new(joint: usize, dof: usize) -> Coord {
+        Coord { joint, dof }
+    }
+}
+
+/// Points a table may hold at most.
+pub const MAX_PROFILE_POINTS: usize = 10_000;
+
+/// A value along time (s): a motor's torque or force, or the value a drive imposes (radians,
+/// mm).
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+pub enum Profile {
+    Constant {
+        value: f64,
+    },
+    /// `value + rate·t`.
+    Linear {
+        value: f64,
+        rate: f64,
+    },
+    /// From `from` to `to` between `start` and `start + duration`, along a cycloidal step
+    /// (`τ − sin(2πτ)/2π`) whose speed and acceleration both start and end at zero.
+    Ramp {
+        from: f64,
+        to: f64,
+        #[serde(default)]
+        start: f64,
+        duration: f64,
+    },
+    /// `offset + amplitude·sin(2π·frequency·t + phase)` (frequency in Hz).
+    Harmonic {
+        #[serde(default)]
+        offset: f64,
+        amplitude: f64,
+        frequency: f64,
+        #[serde(default)]
+        phase: f64,
+    },
+    /// (time, value) points, times increasing: linear in between, held before the first and
+    /// after the last. As a drive its speed jumps at the points (its acceleration is taken as 0).
+    Table {
+        points: Vec<(f64, f64)>,
+    },
+}
+
+impl Profile {
+    /// The value and its first and second time derivatives at `t`.
+    pub fn eval(&self, t: f64) -> (f64, f64, f64) {
+        match self {
+            Profile::Constant { value } => (*value, 0.0, 0.0),
+            Profile::Linear { value, rate } => (value + rate * t, *rate, 0.0),
+            Profile::Ramp { from, to, start, duration } => {
+                let tau = (t - start) / duration;
+                if !(tau > 0.0) {
+                    return (*from, 0.0, 0.0);
+                }
+                if tau >= 1.0 {
+                    return (*to, 0.0, 0.0);
+                }
+                let span = to - from;
+                let (s, c) = (std::f64::consts::TAU * tau).sin_cos();
+                (
+                    from + span * (tau - s / std::f64::consts::TAU),
+                    span / duration * (1.0 - c),
+                    span / (duration * duration) * std::f64::consts::TAU * s,
+                )
+            }
+            Profile::Harmonic { offset, amplitude, frequency, phase } => {
+                let w = std::f64::consts::TAU * frequency;
+                let (s, c) = (w * t + phase).sin_cos();
+                (offset + amplitude * s, amplitude * w * c, -amplitude * w * w * s)
+            }
+            Profile::Table { points } => {
+                let (Some(first), Some(last)) = (points.first(), points.last()) else { return (0.0, 0.0, 0.0) };
+                if t <= first.0 {
+                    return (first.1, 0.0, 0.0);
+                }
+                if t >= last.0 {
+                    return (last.1, 0.0, 0.0);
+                }
+                points
+                    .windows(2)
+                    .find_map(|w| {
+                        let (a, b) = (w.first()?, w.get(1)?);
+                        (t >= a.0 && t < b.0).then(|| {
+                            let slope = (b.1 - a.1) / (b.0 - a.0);
+                            (a.1 + slope * (t - a.0), slope, 0.0)
+                        })
+                    })
+                    .unwrap_or((last.1, 0.0, 0.0))
+            }
+        }
+    }
+
+    fn validate(&self) -> std::result::Result<(), String> {
+        let fin = |x: f64| x.is_finite() && x.abs() < MAX_MAGNITUDE;
+        let ok = match self {
+            Profile::Constant { value } => fin(*value),
+            Profile::Linear { value, rate } => fin(*value) && fin(*rate),
+            Profile::Ramp { from, to, start, duration } => fin(*from) && fin(*to) && fin(*start) && fin(*duration) && *duration > 1e-9,
+            Profile::Harmonic { offset, amplitude, frequency, phase } => {
+                fin(*offset) && fin(*amplitude) && fin(*frequency) && fin(*phase) && frequency.abs() < 1e6
+            }
+            Profile::Table { points } => {
+                if points.is_empty() || points.len() > MAX_PROFILE_POINTS {
+                    return Err(format!("a table needs 1 to {MAX_PROFILE_POINTS} points"));
+                }
+                points.iter().all(|(t, v)| fin(*t) && fin(*v))
+                    && points.windows(2).all(|w| matches!((w.first(), w.get(1)), (Some(a), Some(b)) if b.0 > a.0))
+            }
+        };
+        if ok { Ok(()) } else { Err("a profile's numbers must be finite (ramps need a duration, tables increasing times)".into()) }
+    }
+}
+
+/// A joint value made to follow a profile along time (radians or mm): the joint turns or
+/// slides as told, whatever it takes; [`crate::Sample::drives`] reports what it takes.
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+pub struct Drive {
+    pub at: Coord,
+    pub motion: Profile,
+}
+
+/// A motion link: `follower = ratio·driver + offset`, between values of two joints (a gear
+/// pair: angle to angle; a rack and pinion: angle to distance, the ratio being the pinion's
+/// radius; a screw: angle to distance along the same cylindrical joint, the ratio being
+/// pitch / 2π). Without an offset, the one that holds at the start is kept.
 #[derive(Clone, Copy, Debug, PartialEq, Serialize, Deserialize)]
+pub struct Link {
+    pub driver: Coord,
+    pub follower: Coord,
+    pub ratio: f64,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub offset: Option<f64>,
+}
+
+/// A force element.
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 #[serde(tag = "type", rename_all = "snake_case")]
 pub enum Force {
+    /// A spring and damper on a joint value: the joint is pushed back by
+    /// `stiffness·(value − rest) + damping·rate` (torsional for an angle: mN·mm per radian and
+    /// mN·mm·s; linear for a distance: kg/s² and kg/s).
+    JointSpring {
+        at: Coord,
+        stiffness: f64,
+        #[serde(default)]
+        damping: f64,
+        #[serde(default)]
+        rest: f64,
+    },
+    /// A motor's torque (mN·mm) or force (mN) along a joint value, following a profile: it
+    /// pushes B's side forward and A's side back.
+    Motor { at: Coord, effort: Profile },
     /// A linear spring and damper between two points: the tension is
     /// `stiffness·(length − free_length) + damping·(rate of length) + preload`.
     Spring {
@@ -243,6 +405,10 @@ pub struct Model {
     pub joints: Vec<Joint>,
     #[serde(default)]
     pub forces: Vec<Force>,
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub drives: Vec<Drive>,
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub links: Vec<Link>,
     /// Gravity (mm/s²), e.g. `(0, 0, −9806.65)`.
     #[serde(default)]
     pub gravity: Vec3,
@@ -282,7 +448,10 @@ impl Model {
         if self.forces.len() > MAX_FORCES {
             return Err(DynamicsError::TooLarge(format!("{} force elements (at most {MAX_FORCES})", self.forces.len())));
         }
-        let rows: usize = self.joints.iter().map(|j| j.kind.equations()).sum();
+        if self.drives.len() > MAX_JOINTS || self.links.len() > MAX_JOINTS {
+            return Err(DynamicsError::TooLarge(format!("drives and links: at most {MAX_JOINTS} each")));
+        }
+        let rows: usize = self.joints.iter().map(|j| j.kind.equations()).sum::<usize>() + self.drives.len() + self.links.len();
         if rows > MAX_CONSTRAINT_ROWS {
             return Err(DynamicsError::TooLarge(format!("{rows} constraint equations (at most {MAX_CONSTRAINT_ROWS})")));
         }
@@ -339,8 +508,46 @@ impl Model {
                         return Err(bad(format!("force {i}: point, force and torque must be finite")));
                     }
                 }
+                Force::JointSpring { at, stiffness, damping, rest } => {
+                    self.check_coord(*at).map_err(|e| bad(format!("force {i}: {e}")))?;
+                    let ok = |x: f64| (0.0..MAX_MAGNITUDE).contains(&x);
+                    if !ok(*stiffness) || !ok(*damping) || !rest.is_finite() || rest.abs() >= MAX_MAGNITUDE {
+                        return Err(bad(format!("force {i}: stiffness and damping must be ≥ 0 and finite, rest finite")));
+                    }
+                }
+                Force::Motor { at, effort } => {
+                    self.check_coord(*at).map_err(|e| bad(format!("force {i}: {e}")))?;
+                    effort.validate().map_err(|e| bad(format!("force {i}: {e}")))?;
+                }
             }
         }
+        for (i, d) in self.drives.iter().enumerate() {
+            self.check_coord(d.at).map_err(|e| bad(format!("drive {i}: {e}")))?;
+            d.motion.validate().map_err(|e| bad(format!("drive {i}: {e}")))?;
+        }
+        for (i, l) in self.links.iter().enumerate() {
+            self.check_coord(l.driver).map_err(|e| bad(format!("link {i}: {e}")))?;
+            self.check_coord(l.follower).map_err(|e| bad(format!("link {i}: {e}")))?;
+            if l.driver == l.follower {
+                return Err(bad(format!("link {i}: a value can't drive itself")));
+            }
+            let fin = |x: f64| x.is_finite() && x.abs() < MAX_MAGNITUDE;
+            if !fin(l.ratio) || !l.offset.is_none_or(fin) {
+                return Err(bad(format!("link {i}: ratio and offset must be finite")));
+            }
+        }
+        Ok(())
+    }
+
+    /// The joint and value a [`Coord`] names, if they exist and can be acted on.
+    fn check_coord(&self, c: Coord) -> std::result::Result<(), String> {
+        let j = self.joints.get(c.joint).ok_or_else(|| format!("no joint {}", c.joint))?;
+        if matches!(j.kind, JointKind::Ball | JointKind::Rigid) {
+            return Err(format!("joint {}: not supported yet: springs, motors, drives and links on {:?} joints", c.joint, j.kind));
+        }
+        if c.dof >= j.kind.values().len() {
+            return Err(format!("joint {} has no value {}", c.joint, c.dof));
+        }
         Ok(())
     }
 }

crates/dynamics/src/system.rs

@@ -12,13 +12,20 @@
 //!
 //! through the Schur complement `(J M⁻¹ Jᵀ) λ = J M⁻¹ F − γ` (`linalg::solve_psd`, which takes
 //! repeated joint equations), and `λ` gives the joints' reactions.
+//!
+//! Joint springs and motors act along joint values (generalized forces `Jᵀ Q` along a value's
+//! row); drives add a rheonomic equation `value − f(t) = 0` (so `J u = ḟ`, `J u̇ = f̈ − J̇ u`),
+//! and motion links a linear one between two values. The values they use are also kept in the
+//! state, so an angle counts whole turns.
+
+use std::f64::consts::TAU;
 
 use solidcore_record::Vec3;
 use solidcraft_geom::prelude::*;
 
 use crate::linalg::{Sym, solve_psd};
 use crate::math::{Mat3, Quat, cross2};
-use crate::model::{Force, JointKind, MAX_MAGNITUDE, MAX_PROJECTION_ITERATIONS, Model, marker_axes};
+use crate::model::{Coord, Force, JointKind, MAX_MAGNITUDE, MAX_PROJECTION_ITERATIONS, Model, Profile, marker_axes};
 use crate::{BodyState, DynamicsError, Energy, JointResult, Result};
 
 /// Numbers per body in the flat state: x (3), q (4), v (3), ω (3).
@@ -97,18 +104,32 @@ struct MarkerWorld {
 /// A body's part of one Jacobian row: (linear, angular).
 type Block = (usize, Vec3, Vec3);
 
-/// One constraint equation at a state.
+/// One constraint equation at a state: `Φ = 0`, `J u = rate_target`.
 pub(crate) struct Row {
+    /// A's and B's parts (for a joint's own equations, its two sides).
     a: Option<Block>,
     b: Option<Block>,
+    /// A motion link's driver's parts.
+    c: Option<Block>,
+    d: Option<Block>,
     pub(crate) phi: f64,
-    /// `J̇ u`: the equation's second derivative at zero accelerations.
+    /// `J̇ u` less the imposed acceleration: the equation's second derivative at zero
+    /// accelerations.
     jdot_u: f64,
+    /// The rate a drive imposes (`ḟ`); 0 for the others.
+    rate_target: f64,
+}
+
+fn scaled(b: Option<Block>, k: f64) -> Option<Block> {
+    b.map(|(i, l, a)| (i, l * k, a * k))
 }
 
 impl Row {
+    fn new(a: Option<Block>, b: Option<Block>, phi: f64, jdot_u: f64) -> Row {
+        Row { a, b, c: None, d: None, phi, jdot_u, rate_target: 0.0 }
+    }
     fn blocks(&self) -> impl Iterator<Item = &Block> {
-        self.a.iter().chain(self.b.iter())
+        self.a.iter().chain(self.b.iter()).chain(self.c.iter()).chain(self.d.iter())
     }
     /// `J u`.
     fn rate(&self, kin: &[Kin]) -> f64 {
@@ -116,13 +137,58 @@ impl Row {
     }
 }
 
+/// How a joint value is measured.
+#[derive(Clone, Copy, PartialEq)]
+enum CoordKind {
+    /// B's turn about A's z (from A's x towards A's y).
+    Angle,
+    /// B's origin along one of A's axes (0, 1, 2 = x, y, z).
+    Along(usize),
+}
+
+/// A joint value springs, motors, drives or links act on. Its value is kept in the state too,
+/// so an angle counts whole turns.
+#[derive(Clone, Copy)]
+struct CoordConst {
+    joint: usize,
+    kind: CoordKind,
+}
+
+struct LinkConst {
+    driver: usize,
+    follower: usize,
+    ratio: f64,
+    offset: f64,
+}
+
 /// A model ready to integrate.
+///
+/// The flat state holds every body (`STRIDE` numbers each), then the tracked joint values,
+/// then the work put in (motors, drives, loads) and the energy dissipated (dampers).
 pub(crate) struct System {
     bodies: Vec<BodyConst>,
     joints: Vec<JointConst>,
+    /// Point springs and loads.
     forces: Vec<Force>,
     gravity: Vec3,
     baumgarte: Option<(f64, f64)>,
+    coords: Vec<CoordConst>,
+    /// (value, stiffness, damping, rest).
+    springs: Vec<(usize, f64, f64, f64)>,
+    /// (value, effort).
+    motors: Vec<(usize, Profile)>,
+    /// (value, motion).
+    drives: Vec<(usize, Profile)>,
+    links: Vec<LinkConst>,
+}
+
+/// `θ` turned by whole turns to lie nearest `near`.
+fn unwrap_angle(theta: f64, near: f64) -> f64 {
+    if !near.is_finite() {
+        return theta;
+    }
+    let turns = ((near - theta) / TAU).round();
+    if turns.is_finite() { theta + TAU * turns } else { theta }
 }
 
 /// Accelerations and multipliers at one state.
@@ -164,12 +230,81 @@ impl System {
             .iter()
             .map(|j| Ok(JointConst { kind: j.kind, a: marker_const(&j.a)?, b: marker_const(&j.b)? }))
             .collect::<Result<Vec<_>>>()?;
-        Ok(System { bodies, joints, forces: model.forces.clone(), gravity: model.gravity, baumgarte })
+        let mut sys = System {
+            bodies,
+            joints,
+            forces: model.forces.iter().filter(|f| matches!(f, Force::Spring { .. } | Force::Load { .. })).cloned().collect(),
+            gravity: model.gravity,
+            baumgarte,
+            coords: Vec::new(),
+            springs: Vec::new(),
+            motors: Vec::new(),
+            drives: Vec::new(),
+            links: Vec::new(),
+        };
+        let mut found: Vec<Coord> = Vec::new();
+        let mut index = |c: Coord, sys: &mut System| -> Result<usize> {
+            if let Some(i) = found.iter().position(|f| *f == c) {
+                return Ok(i);
+            }
+            let kind = model.joints.get(c.joint).map(|j| j.kind);
+            let kind = match (kind, c.dof) {
+                (Some(JointKind::Revolute | JointKind::Cylindrical), 0) | (Some(JointKind::Planar), 2) => CoordKind::Angle,
+                (Some(JointKind::Slider), 0) | (Some(JointKind::Cylindrical), 1) => CoordKind::Along(2),
+                (Some(JointKind::Planar), d @ (0 | 1)) => CoordKind::Along(d),
+                _ => return Err(DynamicsError::InvalidModel(format!("joint {} has no value {} to act on", c.joint, c.dof))),
+            };
+            found.push(c);
+            sys.coords.push(CoordConst { joint: c.joint, kind });
+            Ok(found.len() - 1)
+        };
+        for f in &model.forces {
+            match f {
+                Force::JointSpring { at, stiffness, damping, rest } => {
+                    let i = index(*at, &mut sys)?;
+                    sys.springs.push((i, *stiffness, *damping, *rest));
+                }
+                Force::Motor { at, effort } => {
+                    let i = index(*at, &mut sys)?;
+                    sys.motors.push((i, effort.clone()));
+                }
+                Force::Spring { .. } | Force::Load { .. } => {}
+            }
+        }
+        for d in &model.drives {
+            let i = index(d.at, &mut sys)?;
+            sys.drives.push((i, d.motion.clone()));
+        }
+        let mut pending = Vec::new();
+        for l in &model.links {
+            pending.push((index(l.driver, &mut sys)?, index(l.follower, &mut sys)?, l.ratio, l.offset));
+        }
+        // A link without an offset keeps the one that holds at the start.
+        let y = sys.initial_state(model)?;
+        let kin = sys.kinematics(&y);
+        let value = |i: usize| sys.coord_row(&kin, &y, i).phi;
+        let links = pending
+            .into_iter()
+            .map(|(d, f, ratio, offset)| LinkConst { driver: d, follower: f, ratio, offset: offset.unwrap_or_else(|| value(f) - ratio * value(d)) })
+            .collect();
+        sys.links = links;
+        Ok(sys)
+    }
+
+    fn coord_base(&self) -> usize {
+        self.bodies.len() * STRIDE
+    }
+    fn work_base(&self) -> usize {
+        self.coord_base() + self.coords.len()
+    }
+    /// Numbers in the flat state.
+    pub(crate) fn state_len(&self) -> usize {
+        self.work_base() + 2
     }
 
     /// The flat state of the model's starting conditions.
-    pub(crate) fn initial_state(model: &Model) -> Result<Vec<f64>> {
-        let mut y = vec![0.0; model.bodies.len() * STRIDE];
+    pub(crate) fn initial_state(&self, model: &Model) -> Result<Vec<f64>> {
+        let mut y = vec![0.0; self.state_len()];
         for (i, b) in model.bodies.iter().enumerate() {
             let at = i * STRIDE;
             let q = b.orientation.normalized().ok_or_else(|| DynamicsError::InvalidModel(format!("body {i}: orientation is not a rotation")))?;
@@ -178,9 +313,48 @@ impl System {
             put3(&mut y, at + 7, b.velocity);
             put3(&mut y, at + 10, b.angular_velocity);
         }
+        // A driven angle counts its turns from where its motion starts.
+        for (i, motion) in &self.drives {
+            if let Some(s) = y.get_mut(self.coord_base() + i) {
+                *s = motion.eval(0.0).0;
+            }
+        }
+        self.resync(&mut y);
         Ok(y)
     }
 
+    /// Sets each tracked joint value to the one the bodies show (an angle: the turn nearest
+    /// the tracked one).
+    pub(crate) fn resync(&self, y: &mut [f64]) {
+        let kin = self.kinematics(y);
+        let values: Vec<f64> = (0..self.coords.len()).map(|i| self.coord_row(&kin, y, i).phi).collect();
+        for (i, v) in values.into_iter().enumerate() {
+            if let Some(s) = y.get_mut(self.coord_base() + i) {
+                *s = v;
+            }
+        }
+    }
+
+    /// A tracked joint value's equation row: `Φ` is the value itself, `J u` its rate.
+    fn coord_row(&self, kin: &[Kin], y: &[f64], i: usize) -> Row {
+        let (Some(c), tracked) = (self.coords.get(i), y.get(self.coord_base() + i).copied().unwrap_or(f64::NAN)) else {
+            return Row::new(None, None, 0.0, 0.0);
+        };
+        let Some(j) = self.joints.get(c.joint) else { return Row::new(None, None, 0.0, 0.0) };
+        let a = Self::marker_world(kin, &j.a);
+        let b = Self::marker_world(kin, &j.b);
+        let [ax, ay, az] = a.axes;
+        match c.kind {
+            CoordKind::Angle => {
+                let bx = b.axes[0];
+                let theta = unwrap_angle(bx.dot(ay).atan2(bx.dot(ax)), tracked);
+                // θ̇ = (ω_B − ω_A)·z_A; at zero accelerations its rate is (ω_B − ω_A)·(ω_A × z_A).
+                Row::new(a.body.map(|k| (k, Vec3::ZERO, -az)), b.body.map(|k| (k, Vec3::ZERO, az)), theta, (b.w - a.w).dot(a.w.cross(az)))
+            }
+            CoordKind::Along(k) => dot2_row(&a, a.axes.get(k).copied().unwrap_or(az), &b),
+        }
+    }
+
     /// Unit quaternions again after a step.
     pub(crate) fn normalize(&self, y: &mut [f64]) -> Result<()> {
         for i in 0..self.bodies.len() {
@@ -210,17 +384,42 @@ impl System {
         MarkerWorld { body: m.body, r, p: k.x + r, pdot: k.v + k.w.cross(r), axes, w: k.w }
     }
 
-    /// The constraint equations of every joint at `kin`, in joint order.
-    fn rows(&self, kin: &[Kin]) -> Vec<Row> {
+    /// The constraint equations at time `t`: every joint's in joint order, then one per drive
+    /// (`value − f(t) = 0`), then one per link (`follower − ratio·driver − offset = 0`).
+    fn rows(&self, kin: &[Kin], t: f64, y: &[f64]) -> Vec<Row> {
         let mut rows = Vec::new();
         for j in &self.joints {
             let a = Self::marker_world(kin, &j.a);
             let b = Self::marker_world(kin, &j.b);
             joint_rows(j.kind, &a, &b, &mut rows);
         }
+        for (i, motion) in &self.drives {
+            let (f, fd, fdd) = motion.eval(t);
+            let mut r = self.coord_row(kin, y, *i);
+            r.phi -= f;
+            r.jdot_u -= fdd;
+            r.rate_target = fd;
+            rows.push(r);
+        }
+        for l in &self.links {
+            let (f, d) = (self.coord_row(kin, y, l.follower), self.coord_row(kin, y, l.driver));
+            rows.push(Row {
+                a: f.a,
+                b: f.b,
+                c: scaled(d.a, -l.ratio),
+                d: scaled(d.b, -l.ratio),
+                phi: f.phi - l.ratio * d.phi - l.offset,
+                jdot_u: f.jdot_u - l.ratio * d.jdot_u,
+                rate_target: 0.0,
+            });
+        }
         rows
     }
 
+    fn joint_row_count(&self) -> usize {
+        self.joints.iter().map(|j| j.kind.equations()).sum()
+    }
+
     /// `M⁻¹` applied to one body's (force, torque).
     fn minv(&self, kin: &[Kin], body: usize, f: Vec3, t: Vec3) -> (Vec3, Vec3) {
         match (self.bodies.get(body), kin.get(body)) {
@@ -264,8 +463,38 @@ impl System {
         (s, w)
     }
 
-    /// Applied forces and torques (about each centre of mass, world), gyroscopic terms included.
-    fn applied(&self, kin: &[Kin]) -> Vec<(Vec3, Vec3)> {
+    /// Applied forces and torques (about each centre of mass, world), gyroscopic terms included,
+    /// and the power they put in and the power dampers take out.
+    fn applied(&self, kin: &[Kin], t: f64, y: &[f64]) -> (Vec<(Vec3, Vec3)>, f64, f64) {
+        let mut input = 0.0;
+        let mut dissipated = 0.0;
+        let mut out = self.point_forces(kin, &mut input, &mut dissipated);
+        // A generalized force Q along a joint value is Jᵀ Q on the bodies.
+        let mut along = |row: &Row, q: f64| {
+            for (i, l, a) in row.blocks() {
+                if let Some(slot) = out.get_mut(*i) {
+                    slot.0 += *l * q;
+                    slot.1 += *a * q;
+                }
+            }
+        };
+        for (i, k, c, rest) in &self.springs {
+            let row = self.coord_row(kin, y, *i);
+            let rate = row.rate(kin);
+            along(&row, -k * (row.phi - rest) - c * rate);
+            dissipated += c * rate * rate;
+        }
+        for (i, effort) in &self.motors {
+            let row = self.coord_row(kin, y, *i);
+            let q = effort.eval(t).0;
+            along(&row, q);
+            input += q * row.rate(kin);
+        }
+        (out, input, dissipated)
+    }
+
+    /// Gravity, gyroscopic terms, point springs and loads.
+    fn point_forces(&self, kin: &[Kin], input: &mut f64, dissipated: &mut f64) -> Vec<(Vec3, Vec3)> {
         let mut out: Vec<(Vec3, Vec3)> = self
             .bodies
             .iter()
@@ -293,21 +522,25 @@ impl System {
                     let tension = stiffness * (len - free_length) + damping * rate + preload;
                     add(a.body, ra, n * tension, Vec3::ZERO);
                     add(b.body, rb, n * -tension, Vec3::ZERO);
+                    *dissipated += damping * rate * rate;
                 }
                 Force::Load { body, point, force, torque } => {
-                    let r = kin.get(body).map_or(Vec3::ZERO, |k| k.rot.mul_vec(point));
+                    let k = kin.get(body).copied().unwrap_or(GROUND);
+                    let r = k.rot.mul_vec(point);
                     add(Some(body), r, force, torque);
+                    *input += force.dot(k.v + k.w.cross(r)) + torque.dot(k.w);
                 }
+                Force::JointSpring { .. } | Force::Motor { .. } => {}
             }
         }
         out
     }
 
     /// The state's derivative and the joints' multipliers.
-    pub(crate) fn accelerations(&self, y: &[f64]) -> Result<Accel> {
+    pub(crate) fn accelerations(&self, t: f64, y: &[f64]) -> Result<Accel> {
         let kin = self.kinematics(y);
-        let applied = self.applied(&kin);
-        let rows = self.rows(&kin);
+        let (applied, mut input, dissipated) = self.applied(&kin, t, y);
+        let rows = self.rows(&kin, t, y);
         let (s, w) = self.schur(&kin, &rows);
         // Unconstrained accelerations M⁻¹F.
         let free: Vec<(Vec3, Vec3)> = applied.iter().enumerate().map(|(i, (f, t))| self.minv(&kin, i, *f, *t)).collect();
@@ -315,7 +548,7 @@ impl System {
             .iter()
             .map(|r| {
                 let jmf: f64 = r.blocks().map(|(i, l, a)| free.get(*i).map_or(0.0, |(fl, fa)| l.dot(*fl) + a.dot(*fa))).sum();
-                let stab = self.baumgarte.map_or(0.0, |(alpha, beta)| 2.0 * alpha * r.rate(&kin) + beta * beta * r.phi);
+                let stab = self.baumgarte.map_or(0.0, |(alpha, beta)| 2.0 * alpha * (r.rate(&kin) - r.rate_target) + beta * beta * r.phi);
                 jmf + r.jdot_u + stab
             })
             .collect();
@@ -338,25 +571,50 @@ impl System {
             put3(&mut ydot, at + 7, a.0);
             put3(&mut ydot, at + 10, a.1);
         }
+        for i in 0..self.coords.len() {
+            let rate = self.coord_row(&kin, y, i).rate(&kin);
+            if let Some(s) = ydot.get_mut(self.coord_base() + i) {
+                *s = rate;
+            }
+        }
+        // A drive's generalized force is −λ along its value: its power is −λ·(value rate).
+        let first_drive = self.joint_row_count();
+        for k in 0..self.drives.len() {
+            if let (Some(r), Some(l)) = (rows.get(first_drive + k), lambda.get(first_drive + k)) {
+                input -= l * r.rate(&kin);
+            }
+        }
+        let wb = self.work_base();
+        for (k, p) in [input, dissipated].into_iter().enumerate() {
+            if let Some(s) = ydot.get_mut(wb + k) {
+                *s = p;
+            }
+        }
         if !ydot.iter().all(|x| x.is_finite()) {
             return Err(DynamicsError::Diverged { time: f64::NAN });
         }
         Ok(Accel { ydot, lambda, rows, rank })
     }
 
-    /// The largest joint equation error at `y`.
-    pub(crate) fn constraint_error(&self, y: &[f64]) -> f64 {
-        self.rows(&self.kinematics(y)).iter().map(|r| r.phi.abs()).fold(0.0, f64::max)
+    /// What each drive applies along its value (mN·mm or mN), from the multipliers.
+    pub(crate) fn drive_efforts(&self, acc: &Accel) -> Vec<f64> {
+        let first = self.joint_row_count();
+        (0..self.drives.len()).map(|k| -acc.lambda.get(first + k).copied().unwrap_or(0.0)).collect()
+    }
+
+    /// The largest constraint equation error at `y` and time `t`.
+    pub(crate) fn constraint_error(&self, t: f64, y: &[f64]) -> f64 {
+        self.rows(&self.kinematics(y), t, y).iter().map(|r| r.phi.abs()).fold(0.0, f64::max)
     }
 
     /// Moves the bodies the least (mass-weighted) onto the joints: Gauss–Newton on `Φ = 0`.
     /// Returns the error left.
-    pub(crate) fn project_positions(&self, y: &mut [f64], tol: f64) -> Result<f64> {
+    pub(crate) fn project_positions(&self, t: f64, y: &mut [f64], tol: f64) -> Result<f64> {
         let mut err;
         let mut iteration = 0;
         loop {
             let kin = self.kinematics(y);
-            let rows = self.rows(&kin);
+            let rows = self.rows(&kin, t, y);
             err = rows.iter().map(|r| r.phi.abs()).fold(0.0, f64::max);
             if !(err > tol) || iteration >= MAX_PROJECTION_ITERATIONS {
                 break;
@@ -387,15 +645,16 @@ impl System {
         Ok(err)
     }
 
-    /// Removes the velocities the joints don't allow (mass-weighted): `J u = 0`.
-    pub(crate) fn project_velocities(&self, y: &mut [f64]) -> Result<()> {
+    /// Removes the velocities the joints don't allow (mass-weighted): `J u = ḟ` (0 but for
+    /// drives).
+    pub(crate) fn project_velocities(&self, t: f64, y: &mut [f64]) -> Result<()> {
         let kin = self.kinematics(y);
-        let rows = self.rows(&kin);
+        let rows = self.rows(&kin, t, y);
         if rows.is_empty() {
             return Ok(());
         }
         let (s, w) = self.schur(&kin, &rows);
-        let ju: Vec<f64> = rows.iter().map(|r| r.rate(&kin)).collect();
+        let ju: Vec<f64> = rows.iter().map(|r| r.rate(&kin) - r.rate_target).collect();
         let (mu, _) = solve_psd(s, &ju, RANK_TOL).ok_or(DynamicsError::Singular { time: f64::NAN })?;
         for (wr, m) in w.iter().zip(&mu) {
             for (i, ml, ma) in wr {
@@ -417,7 +676,7 @@ impl System {
             .collect()
     }
 
-    /// Kinetic, gravity and spring energy.
+    /// Kinetic, gravity and spring energy, and the work put in and dissipated so far.
     pub(crate) fn energy(&self, y: &[f64]) -> Energy {
         let kin = self.kinematics(y);
         let mut e = Energy::default();
@@ -433,6 +692,13 @@ impl System {
                 e.spring += 0.5 * stiffness * stretch * stretch + preload * stretch;
             }
         }
+        for (i, k, _, rest) in &self.springs {
+            let stretch = self.coord_row(&kin, y, *i).phi - rest;
+            e.spring += 0.5 * k * stretch * stretch;
+        }
+        let wb = self.work_base();
+        e.input = y.get(wb).copied().unwrap_or(0.0);
+        e.dissipated = y.get(wb + 1).copied().unwrap_or(0.0);
         e
     }
 
@@ -477,19 +743,19 @@ impl System {
 /// `(Φ, J, J̇u)` for one body point's world component along `e`: `e·(p_B − p_A)`.
 fn point_row(a: &MarkerWorld, b: &MarkerWorld, e: Vec3) -> Row {
     let acc = |m: &MarkerWorld| cross2(m.w, m.r);
-    Row { a: a.body.map(|i| (i, -e, -a.r.cross(e))), b: b.body.map(|i| (i, e, b.r.cross(e))), phi: e.dot(b.p - a.p), jdot_u: e.dot(acc(b) - acc(a)) }
+    Row::new(a.body.map(|i| (i, -e, -a.r.cross(e))), b.body.map(|i| (i, e, b.r.cross(e))), e.dot(b.p - a.p), e.dot(acc(b) - acc(a)))
 }
 
 /// `u·v = 0` for a direction `u` of A and `v` of B.
 fn dot1_row(a: &MarkerWorld, u: Vec3, b: &MarkerWorld, v: Vec3) -> Row {
     let (ud, vd) = (a.w.cross(u), b.w.cross(v));
     let (udd, vdd) = (cross2(a.w, u), cross2(b.w, v));
-    Row {
-        a: a.body.map(|i| (i, Vec3::ZERO, u.cross(v))),
-        b: b.body.map(|i| (i, Vec3::ZERO, v.cross(u))),
-        phi: u.dot(v),
-        jdot_u: udd.dot(v) + 2.0 * ud.dot(vd) + u.dot(vdd),
-    }
+    Row::new(
+        a.body.map(|i| (i, Vec3::ZERO, u.cross(v))),
+        b.body.map(|i| (i, Vec3::ZERO, v.cross(u))),
+        u.dot(v),
+        udd.dot(v) + 2.0 * ud.dot(vd) + u.dot(vdd),
+    )
 }
 
 /// `d·u = 0` for `d = p_B − p_A` and a direction `u` of A.
@@ -498,12 +764,12 @@ fn dot2_row(a: &MarkerWorld, u: Vec3, b: &MarkerWorld) -> Row {
     let dd = b.pdot - a.pdot;
     let ddd = cross2(b.w, b.r) - cross2(a.w, a.r);
     let (ud, udd) = (a.w.cross(u), cross2(a.w, u));
-    Row {
-        a: a.body.map(|i| (i, -u, u.cross(d) - a.r.cross(u))),
-        b: b.body.map(|i| (i, u, b.r.cross(u))),
-        phi: d.dot(u),
-        jdot_u: ddd.dot(u) + 2.0 * dd.dot(ud) + d.dot(udd),
-    }
+    Row::new(
+        a.body.map(|i| (i, -u, u.cross(d) - a.r.cross(u))),
+        b.body.map(|i| (i, u, b.r.cross(u))),
+        d.dot(u),
+        ddd.dot(u) + 2.0 * dd.dot(ud) + d.dot(udd),
+    )
 }
 
 fn joint_rows(kind: JointKind, a: &MarkerWorld, b: &MarkerWorld, rows: &mut Vec<Row>) {
@@ -576,7 +842,7 @@ pub(crate) mod testing {
     /// `(Φ, J u, J̇ u)` of every row at `y`.
     pub(crate) fn rows_at(sys: &System, y: &[f64]) -> Vec<(f64, f64, f64)> {
         let kin = sys.kinematics(y);
-        sys.rows(&kin).iter().map(|r| (r.phi, r.rate(&kin), r.jdot_u)).collect()
+        sys.rows(&kin, 0.0, y).iter().map(|r| (r.phi, r.rate(&kin), r.jdot_u)).collect()
     }
 
     /// The state moved along its velocities for `h` (positions and orientations only).

crates/dynamics/src/tests.rs

@@ -38,7 +38,7 @@ fn pendulum(len: f64, theta: f64, omega: f64, inertia: f64) -> Model {
         a: Marker::ground(Vec3::ZERO, Vec3::Y, Vec3::X),
         b: Marker::new(Some(0), Vec3::new(0.0, 0.0, len), Vec3::Y, Vec3::X),
     };
-    Model { bodies: vec![body], joints: vec![joint], forces: vec![], gravity: down() }
+    Model { bodies: vec![body], joints: vec![joint], forces: vec![], drives: vec![], links: vec![], gravity: down() }
 }
 
 /// Times where `f` crosses zero upwards, linearly interpolated between samples.
@@ -68,7 +68,7 @@ fn free_fall_follows_the_parabola() {
     let mut body = Body::at_rest(2.5, Vec3::new(10.0, 20.0, 30.0), Vec3::new(1.0, 2.0, 3.0));
     body.velocity = Vec3::new(10.0, -5.0, 50.0);
     body.angular_velocity = Vec3::new(0.0, 0.0, 1.0);
-    let model = Model { bodies: vec![body.clone()], joints: vec![], forces: vec![], gravity: down() };
+    let model = Model { bodies: vec![body.clone()], joints: vec![], forces: vec![], drives: vec![], links: vec![], gravity: down() };
     let traj = ok(simulate(&model, &Settings::rk4(1.0, 0.01, 0.1)));
     assert_eq!(traj.samples.len(), 11);
     for s in &traj.samples {
@@ -158,6 +158,7 @@ fn double_pendulum() -> Model {
         ],
         forces: vec![],
         gravity: down(),
+        ..Model::default()
     }
 }
 
@@ -215,6 +216,7 @@ fn slider_crank_follows_its_closed_form() {
         ],
         forces: vec![],
         gravity: Vec3::ZERO,
+        ..Model::default()
     };
     let traj = ok(simulate(&model, &Settings::rk4(2.0, 1e-3, 1e-2)));
     // A planar linkage built from 3D joints repeats three equations; they are solved, not refused.
@@ -256,6 +258,7 @@ fn spring_mass(damping: f64) -> Model {
             preload: 0.0,
         }],
         gravity: down(),
+        ..Model::default()
     }
 }
 
@@ -294,7 +297,7 @@ fn torque_free_body_keeps_energy_and_momentum() {
     let mut body = Body::at_rest(1.0, Vec3::new(1000.0, 2000.0, 3000.0), Vec3::ZERO);
     body.orientation = Quat::from_axis_angle(Vec3::new(1.0, 2.0, 3.0), 0.7);
     body.angular_velocity = Vec3::new(1.0, 0.3, 5.0);
-    let model = Model { bodies: vec![body], joints: vec![], forces: vec![], gravity: Vec3::ZERO };
+    let model = Model { bodies: vec![body], joints: vec![], forces: vec![], drives: vec![], links: vec![], gravity: Vec3::ZERO };
     let traj = ok(simulate(&model, &Settings::rk4(2.0, 1e-4, 1e-2)));
     let momentum = |s: &Sample| {
         let b = s.bodies.first().copied();
@@ -329,6 +332,7 @@ fn spherical_pendulum_keeps_energy_and_vertical_momentum() {
         }],
         forces: vec![],
         gravity: down(),
+        ..Model::default()
     };
     let traj = ok(simulate(&model, &Settings::rk4(3.0, 5e-4, 1e-2)));
     let lz = |s: &Sample| {
@@ -369,9 +373,10 @@ fn jacobians_match_finite_differences() {
                 a: Marker::new(a_body, Vec3::new(4.0, -3.0, 7.0), Vec3::new(0.2, 0.5, 1.0), Vec3::new(1.0, 0.0, 0.3)),
                 b: Marker::new(Some(1), Vec3::new(-6.0, 2.0, 1.0), Vec3::new(-0.4, 1.0, 0.1), Vec3::new(0.0, 0.3, 1.0)),
             };
-            let model = Model { bodies: vec![a.clone(), b.clone()], joints: vec![joint], forces: vec![], gravity: Vec3::ZERO };
+            let model =
+                Model { bodies: vec![a.clone(), b.clone()], joints: vec![joint], forces: vec![], drives: vec![], links: vec![], gravity: Vec3::ZERO };
             let sys = ok(System::new(&model, None));
-            let y = ok(System::initial_state(&model));
+            let y = ok(sys.initial_state(&model));
             let h = 1e-4;
             let (now, plus, minus) = (
                 testing::rows_at(&sys, &y),
@@ -400,6 +405,7 @@ fn joint_values_read_the_relative_motion() {
             joints: vec![Joint { kind, a: Marker::ground(Vec3::ZERO, Vec3::Z, Vec3::X), b: Marker::new(Some(0), Vec3::ZERO, Vec3::Z, Vec3::X) }],
             forces: vec![],
             gravity: Vec3::ZERO,
+            ..Model::default()
         };
         let traj = ok(simulate(&model, &Settings::rk4(0.01, 0.01, 0.01)));
         traj.samples.first().and_then(|s| s.joints.first()).map(|j| j.values.clone()).unwrap_or_default()
@@ -523,6 +529,10 @@ fn hostile_input_is_an_error_not_a_panic() {
 fn models_round_trip_through_json() {
     let mut model = spring_mass(1.5);
     model.forces.push(Force::Load { body: 0, point: Vec3::new(1.0, 0.0, 0.0), force: Vec3::new(0.0, 5.0, 0.0), torque: Vec3::ZERO });
+    model.forces.push(Force::JointSpring { at: Coord::new(0, 0), stiffness: 3.0, damping: 0.5, rest: 1.0 });
+    model.forces.push(Force::Motor { at: Coord::new(0, 0), effort: Profile::Table { points: vec![(0.0, 1.0), (2.0, 3.0)] } });
+    model.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Ramp { from: 0.0, to: 1.0, start: 0.5, duration: 2.0 } });
+    model.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio: 2.0, offset: Some(0.5) });
     let text = match serde_json::to_string(&model) {
         Ok(t) => t,
         Err(e) => panic!("{e}"),
@@ -538,3 +548,253 @@ fn models_round_trip_through_json() {
     };
     assert!(settings.projection && settings.validate().is_ok());
 }
+
+// Joint springs, motors, drives and motion links.
+
+/// `a − b` turned into (−π, π].
+fn wrap(x: f64) -> f64 {
+    (x + PI).rem_euclid(TAU) - PI
+}
+
+/// A wheel turning about Z on a revolute to the ground at `at`, its centre of mass on the axis.
+/// Wheels turning about Z on revolutes to the ground, centres of mass on their axes (inertia,
+/// centre); joint `i` holds body `i`.
+fn rotors(parts: &[(f64, Vec3)]) -> Model {
+    let mut model = Model::default();
+    for (i, (inertia, at)) in parts.iter().enumerate() {
+        model.bodies.push(Body::at_rest(1.0, Vec3::new(*inertia, *inertia, *inertia), *at));
+        model.joints.push(Joint {
+            kind: JointKind::Revolute,
+            a: Marker::ground(*at, Vec3::Z, Vec3::X),
+            b: Marker::new(Some(i), Vec3::ZERO, Vec3::Z, Vec3::X),
+        });
+    }
+    model
+}
+
+fn value(s: &Sample, joint: usize, dof: usize) -> f64 {
+    s.joints.get(joint).and_then(|j| j.values.get(dof)).copied().unwrap_or(f64::NAN)
+}
+
+#[test]
+fn profiles_give_consistent_derivatives() {
+    let profiles = [
+        Profile::Constant { value: 2.0 },
+        Profile::Linear { value: 1.0, rate: -3.0 },
+        Profile::Ramp { from: 0.5, to: 2.0, start: 0.2, duration: 0.6 },
+        Profile::Harmonic { offset: 1.0, amplitude: 0.3, frequency: 2.0, phase: 0.4 },
+    ];
+    let h = 1e-5;
+    for p in &profiles {
+        for k in 0..100 {
+            let t = k as f64 * 0.0123;
+            let (f, fd, fdd) = p.eval(t);
+            let (fp, fdp, _) = p.eval(t + h);
+            let (fm, fdm, _) = p.eval(t - h);
+            assert!((fd - (fp - fm) / (2.0 * h)).abs() < 1e-5 * (1.0 + fd.abs()), "{p:?} at {t}: ḟ");
+            assert!((fdd - (fdp - fdm) / (2.0 * h)).abs() < 1e-3 * (1.0 + fdd.abs()), "{p:?} at {t}: f̈");
+            assert!(f.is_finite());
+        }
+    }
+    let ramp = Profile::Ramp { from: 0.5, to: 2.0, start: 0.2, duration: 0.6 };
+    assert_eq!(ramp.eval(0.0).0, 0.5);
+    assert_eq!(ramp.eval(0.8).0, 2.0);
+    assert!((ramp.eval(0.5).0 - 1.25).abs() < 1e-12);
+    let table = Profile::Table { points: vec![(0.0, 1.0), (1.0, 3.0), (2.0, 0.0)] };
+    assert_eq!(table.eval(-1.0), (1.0, 0.0, 0.0));
+    assert_eq!(table.eval(0.5), (2.0, 2.0, 0.0));
+    assert_eq!(table.eval(1.5), (1.5, -3.0, 0.0));
+    assert_eq!(table.eval(9.0), (0.0, 0.0, 0.0));
+}
+
+#[test]
+fn driven_pendulum_reaches_its_commanded_angle_and_holds_it() {
+    // A drive lifts the pendulum from hanging to horizontal along a cycloidal ramp in 1 s,
+    // then holds it: the angle follows the ramp, and the holding torque is m·g·L.
+    let (len, mass) = (100.0, 1.0);
+    let mut model = pendulum(len, 0.0, 0.0, 40.0);
+    let ramp = Profile::Ramp { from: 0.0, to: PI / 2.0, start: 0.0, duration: 1.0 };
+    model.drives.push(Drive { at: Coord::new(0, 0), motion: ramp.clone() });
+    let traj = ok(simulate(&model, &Settings::rk4(1.5, 1e-3, 1e-2)));
+    let b0 = traj.samples.first().map(|s| s.energy.balance()).unwrap_or(f64::NAN);
+    for s in &traj.samples {
+        let angle = value(s, 0, 0);
+        assert!((angle - ramp.eval(s.time).0).abs() < 1e-9, "t={}: angle {angle} vs {}", s.time, ramp.eval(s.time).0);
+        // Work put in = kinetic + gravity energy gained.
+        assert!((s.energy.balance() - b0).abs() < 1e-6 * G * len, "t={}: balance {}", s.time, s.energy.balance() - b0);
+    }
+    let held: Vec<&Sample> = traj.samples.iter().filter(|s| s.time >= 1.0).collect();
+    assert!(held.len() > 40);
+    for s in held {
+        let effort = s.drives.first().copied().unwrap_or(f64::NAN);
+        assert!((effort.abs() - mass * G * len).abs() < 1e-6 * G * len, "t={}: holding torque {effort}", s.time);
+        assert!((s.energy.input - mass * G * len).abs() < 1e-6 * G * len, "work put in {}", s.energy.input);
+        assert!(s.energy.kinetic < 1e-9 * G * len);
+    }
+}
+
+#[test]
+fn driven_speed_counts_whole_turns() {
+    // 10 rad/s for 2 s: more than three turns; the driven angle never jumps a turn.
+    let mut model = rotors(&[(500.0, Vec3::ZERO)]);
+    model.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Linear { value: 0.0, rate: 10.0 } });
+    let traj = ok(simulate(&model, &Settings::rk4(2.0, 1e-3, 1e-2)));
+    for s in &traj.samples {
+        assert!(wrap(value(s, 0, 0) - 10.0 * s.time).abs() < 1e-9, "t={}", s.time);
+        let w = s.bodies.first().map(|b| b.angular_velocity.z).unwrap_or(f64::NAN);
+        assert!((w - 10.0).abs() < 1e-9);
+        assert!(s.drives.first().is_some_and(|e| e.abs() < 1e-6), "{:?}", s.drives);
+    }
+    assert!(traj.stats.max_constraint_error < 1e-9);
+}
+
+#[test]
+fn torsion_spring_period() {
+    // ω = √(k/I) = √(5e5 / 500) rad/s; released from 0.3 rad.
+    let (inertia, k) = (500.0_f64, 5e5_f64);
+    let w = (k / inertia).sqrt();
+    let mut model = rotors(&[(inertia, Vec3::ZERO)]);
+    if let Some(b) = model.bodies.first_mut() {
+        b.orientation = Quat::from_axis_angle(Vec3::Z, 0.3);
+    }
+    model.forces.push(Force::JointSpring { at: Coord::new(0, 0), stiffness: k, damping: 0.0, rest: 0.0 });
+    let traj = ok(simulate(&model, &Settings::rk4(1.0, 1e-4, 1e-3)));
+    for s in &traj.samples {
+        let expect = 0.3 * (w * s.time).cos();
+        assert!((value(s, 0, 0) - expect).abs() < 1e-7, "t={}: {} vs {expect}", s.time, value(s, 0, 0));
+    }
+    let measured = mean_period(&upward_crossings(&traj, |s| value(s, 0, 0)));
+    assert!((measured - TAU / w).abs() < 1e-5 * TAU / w);
+    let e0 = traj.samples.first().map(|s| s.energy.total()).unwrap_or(0.0);
+    assert!((e0 - 0.5 * k * 0.09).abs() < 1e-9 * e0);
+    // With damping the energy left plus the energy dissipated stays what it was.
+    if let Some(Force::JointSpring { damping, .. }) = model.forces.first_mut() {
+        *damping = 2.0 * 0.05 * (k * inertia).sqrt();
+    }
+    let traj = ok(simulate(&model, &Settings::rk4(1.0, 1e-4, 1e-2)));
+    let last = traj.samples.last().map(|s| s.energy).unwrap_or_default();
+    assert!(last.total() < 0.2 * e0 && last.dissipated > 0.8 * e0);
+    assert!(traj.samples.iter().all(|s| (s.energy.balance() - e0).abs() < 1e-7 * e0));
+}
+
+#[test]
+fn gear_pair_keeps_its_ratio_and_motor_work_is_kinetic_energy() {
+    // A motor's constant torque τ on gear 1; gear 2 turns at −r₁/r₂ = −0.5 of it. The pair
+    // accelerates as one inertia I₁ + 0.25·I₂: θ₁ = ½(τ/I_eff)t², and the motor's work τ·θ₁ is
+    // all kinetic energy. Over 3 s gear 1 makes more than half a turn past ±π.
+    let (i1, i2, ratio, tau) = (1000.0, 2000.0, -0.5, 1500.0);
+    let alpha = tau / (i1 + ratio * ratio * i2);
+    let mut model = rotors(&[(i1, Vec3::ZERO), (i2, Vec3::new(30.0, 0.0, 0.0))]);
+    model.forces.push(Force::Motor { at: Coord::new(0, 0), effort: Profile::Constant { value: tau } });
+    model.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio, offset: None });
+    let traj = ok(simulate(&model, &Settings::rk4(3.0, 1e-3, 1e-2)));
+    for s in &traj.samples {
+        let theta = 0.5 * alpha * s.time * s.time;
+        assert!(wrap(value(s, 0, 0) - theta).abs() < 1e-8, "t={}: gear 1 {} vs {theta}", s.time, value(s, 0, 0));
+        assert!(wrap(value(s, 1, 0) - ratio * theta).abs() < 1e-8, "t={}: gear 2", s.time);
+        assert!((s.energy.input - tau * theta).abs() < 1e-6 * tau * 4.5, "t={}: work {}", s.time, s.energy.input);
+        assert!((s.energy.kinetic - s.energy.input).abs() < 1e-6 * tau * 4.5, "t={}: kinetic {}", s.time, s.energy.kinetic);
+    }
+    assert!(0.5 * alpha * 9.0 > PI);
+}
+
+#[test]
+fn rack_and_pinion_follow_the_pinion_radius() {
+    // A pinion of radius 20 mm drives a rack on a slider along X; a harmonic motor torque. The
+    // rack's travel is 20·θ, and the motor's work is the kinetic energy of both.
+    let mut model = rotors(&[(800.0, Vec3::ZERO)]);
+    model.bodies.push(Body::at_rest(0.5, Vec3::new(100.0, 100.0, 100.0), Vec3::new(0.0, 20.0, 0.0)));
+    model.joints.push(Joint {
+        kind: JointKind::Slider,
+        a: Marker::ground(Vec3::new(0.0, 20.0, 0.0), Vec3::X, Vec3::Y),
+        b: Marker::new(Some(1), Vec3::ZERO, Vec3::X, Vec3::Y),
+    });
+    model
+        .forces
+        .push(Force::Motor { at: Coord::new(0, 0), effort: Profile::Harmonic { offset: 0.0, amplitude: 2000.0, frequency: 1.0, phase: 0.0 } });
+    model.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio: 20.0, offset: None });
+    let traj = ok(simulate(&model, &Settings::rk4(2.0, 1e-3, 1e-2)));
+    // I_eff = 800 + 0.5·20²; θ̈ = τ(t)/I_eff with τ = A sin(2πt): θ = A/I_eff·(t/2π − sin(2πt)/4π²).
+    let i_eff = 800.0 + 0.5 * 400.0;
+    for s in &traj.samples {
+        let t = s.time;
+        let theta = 2000.0 / i_eff * (t / TAU - (TAU * t).sin() / (TAU * TAU));
+        assert!((value(s, 0, 0) - theta).abs() < 1e-8, "t={t}: pinion {} vs {theta}", value(s, 0, 0));
+        assert!((value(s, 1, 0) - 20.0 * theta).abs() < 1e-7, "t={t}: rack {}", value(s, 1, 0));
+        assert!((s.energy.kinetic - s.energy.input).abs() < 1e-8 * 2000.0, "t={t}: {:?}", s.energy);
+    }
+}
+
+#[test]
+fn screw_turns_as_it_falls() {
+    // A nut on a vertical cylindrical joint, its travel tied to its turn by a 5 mm pitch, falls
+    // under gravity: z̈ = −m·g·k² / (I + m·k²) with k = pitch / 2π.
+    let (mass, inertia, k) = (0.2, 50.0, 5.0 / TAU);
+    let model = Model {
+        bodies: vec![Body::at_rest(mass, Vec3::new(inertia, inertia, inertia), Vec3::ZERO)],
+        joints: vec![Joint {
+            kind: JointKind::Cylindrical,
+            a: Marker::ground(Vec3::ZERO, Vec3::Z, Vec3::X),
+            b: Marker::new(Some(0), Vec3::ZERO, Vec3::Z, Vec3::X),
+        }],
+        links: vec![Link { driver: Coord::new(0, 0), follower: Coord::new(0, 1), ratio: k, offset: None }],
+        gravity: down(),
+        ..Model::default()
+    };
+    let traj = ok(simulate(&model, &Settings::rk4(1.0, 1e-3, 1e-2)));
+    let a = -mass * G * k * k / (inertia + mass * k * k);
+    for s in &traj.samples {
+        let z = s.bodies.first().map(|b| b.position.z).unwrap_or(f64::NAN);
+        assert!((z - 0.5 * a * s.time * s.time).abs() < 1e-7, "t={}: z {z}", s.time);
+        assert!(wrap(value(s, 0, 0) - z / k).abs() < 1e-8, "t={}: turn", s.time);
+        assert!(s.energy.balance().abs() < 1e-6 * mass * G, "t={}: {:?}", s.time, s.energy);
+    }
+    // It went down more than one turn.
+    assert!(0.5 * a < -5.0);
+}
+
+#[test]
+fn hostile_springs_motors_drives_and_links_are_errors() {
+    let good = rotors(&[(500.0, Vec3::ZERO), (500.0, Vec3::new(30.0, 0.0, 0.0))]);
+    let mut bad: Vec<Model> = Vec::new();
+    let mut with = |f: &dyn Fn(&mut Model)| {
+        let mut m = good.clone();
+        f(&mut m);
+        bad.push(m);
+    };
+    with(&|m| m.drives.push(Drive { at: Coord::new(5, 0), motion: Profile::Constant { value: 0.0 } }));
+    with(&|m| m.drives.push(Drive { at: Coord::new(0, 1), motion: Profile::Constant { value: 0.0 } }));
+    with(&|m| m.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Constant { value: f64::NAN } }));
+    with(&|m| m.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Ramp { from: 0.0, to: 1.0, start: 0.0, duration: 0.0 } }));
+    with(&|m| m.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Table { points: vec![] } }));
+    with(&|m| m.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Table { points: vec![(1.0, 0.0), (0.5, 1.0)] } }));
+    with(&|m| m.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Table { points: vec![(0.0, 0.0); MAX_PROFILE_POINTS + 1] } }));
+    with(&|m| m.forces.push(Force::JointSpring { at: Coord::new(0, 0), stiffness: -1.0, damping: 0.0, rest: 0.0 }));
+    with(&|m| m.forces.push(Force::JointSpring { at: Coord::new(0, 0), stiffness: 1.0, damping: f64::INFINITY, rest: 0.0 }));
+    with(&|m| m.forces.push(Force::Motor { at: Coord::new(9, 0), effort: Profile::Constant { value: 1.0 } }));
+    with(&|m| {
+        m.forces
+            .push(Force::Motor { at: Coord::new(0, 0), effort: Profile::Harmonic { offset: 0.0, amplitude: 1.0, frequency: f64::NAN, phase: 0.0 } })
+    });
+    with(&|m| m.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(0, 0), ratio: 1.0, offset: None }));
+    with(&|m| m.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio: f64::NAN, offset: None }));
+    with(&|m| m.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio: 1.0, offset: Some(f64::INFINITY) }));
+    with(&|m| m.links = vec![Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio: 1.0, offset: None }; MAX_JOINTS + 1]);
+    with(&|m| {
+        // Ball and rigid joints have no value to act on yet.
+        if let Some(j) = m.joints.get_mut(0) {
+            j.kind = JointKind::Ball;
+        }
+        m.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Constant { value: 0.0 } });
+    });
+    for (i, m) in bad.iter().enumerate() {
+        assert!(simulate(m, &Settings::rk4(0.1, 1e-3, 1e-2)).is_err(), "case {i} should be refused");
+    }
+    // Links that fight each other, and drives that can't be met, stop or finish but never panic.
+    let mut locked = good.clone();
+    locked.links.push(Link { driver: Coord::new(0, 0), follower: Coord::new(1, 0), ratio: 1.0, offset: None });
+    locked.links.push(Link { driver: Coord::new(1, 0), follower: Coord::new(0, 0), ratio: 2.0, offset: None });
+    locked.drives.push(Drive { at: Coord::new(0, 0), motion: Profile::Harmonic { offset: 0.0, amplitude: 1e6, frequency: 1e3, phase: 0.0 } });
+    let _ = simulate(&locked, &Settings::rk4(0.1, 1e-3, 1e-2));
+    let _ = simulate(&locked, &Settings::adaptive(0.1, 1e-2, 1e-9, 1e-9));
+}

crates/engine/examples/opus_quality_fixture.rs

@@ -0,0 +1,231 @@
+//! Prepare an explicitly shaded OPUS copy and physical CPU/GPU reference setups.
+//! No render is started. Geometry and the original OPUS Master setup are retained.
+use serde_json::{Value, json};
+use solidcore_record::Vec3;
+use solidcraft_engine::{
+    Session,
+    doc::{Document, FeatureKind, MeshData, render_settings::RenderSetup},
+};
+use solidcraft_geom::prelude::*;
+use std::{error::Error, fs, path::PathBuf, sync::Arc};
+
+fn require(condition: bool, message: &str) -> Result<(), Box<dyn Error>> {
+    if condition { Ok(()) } else { Err(message.into()) }
+}
+
+const CURVED: &[&str] = &[
+    "A3 - continuous sixteen facet freeform glass knot",
+    "A3 - six lobe quilted aspheric witness optic",
+    "Glass - smoked rounded toroid",
+    "Glass - clear calibration sphere",
+    "O2 - Lens 1 - Biconvex crown",
+    "O2 - Lens 2 - Biconcave flint",
+    "O2 - Lens 3 - Thick meniscus",
+    "O2 - Lens 4 - Plano convex magnifier",
+    "O2 - Lens 5 - Aspheric correction optic",
+    "R2 - clear chest reactor lens",
+    "R2 - near clear glass eye",
+    "R2 - far clear glass eye",
+    "S2 - amber solid ellipsoid",
+    "S2 - cobalt fluted solid decanter",
+    "R2 - thorax ivory swept breastplates",
+    "S2 - glass gallery turned wood pedestal -217",
+    "S2 - glass gallery turned wood pedestal 211",
+];
+
+fn scene_counts(scene: &Value) -> Result<(usize, u64), Box<dyn Error>> {
+    let bodies = scene["bodies"].as_array().ok_or("missing scene bodies")?;
+    let triangles = bodies
+        .iter()
+        .try_fold(0u64, |sum, body| sum.checked_add(body["triangles"].as_u64().ok_or("missing triangle count")?).ok_or("triangle sum overflow"))?;
+    Ok((bodies.len(), triangles))
+}
+
+fn physical(master: &RenderSetup, cpu: bool, pilot: bool) -> Result<Value, Box<dyn Error>> {
+    let mut setup = serde_json::to_value(master)?;
+    let mut optics = setup["optics"].as_array().ok_or("missing optics")?.clone();
+    for binding in &mut optics {
+        binding["optics"]["shadow_transmission"] = json!(false);
+    }
+    setup["optics"] = json!(optics);
+    setup["mode"] = json!("final");
+    setup["width"] = json!(if pilot { 320 } else { 3840 });
+    setup["height"] = json!(if pilot { 180 } else { 2160 });
+    let samples = if pilot { 8u32 } else { 4096u32 };
+    let mut options = setup["job"]["options"].clone();
+    options["texture_filtering"] = json!(true);
+    options["linear_exr"] = json!(true);
+    options["max_depth"] = json!(64);
+    options["samples"] = json!(samples);
+    options["nested_media"] = json!(true);
+    options["denoise"] = json!(false);
+    if cpu {
+        let lighting = &options["lighting"];
+        let area_lights = lighting["area_lights"]
+            .as_array()
+            .ok_or("missing area lights")?
+            .iter()
+            .map(|a| {
+                let radiance: [f64; 3] = serde_json::from_value(a["radiance"].clone())?;
+                let intensity = radiance.into_iter().fold(0.0, f64::max);
+                let color = radiance.map(|v| if intensity > 0.0 { v / intensity } else { 0.0 });
+                // GPU stores half-edges; the CPU rectangle contract takes full sides.
+                let u: [f64; 3] = serde_json::from_value(a["u"].clone())?;
+                let v: [f64; 3] = serde_json::from_value(a["v"].clone())?;
+                Ok(json!({"center_mm":a["center"],"edge_u_mm":u.map(|x|x*2.0),"edge_v_mm":v.map(|x|x*2.0),"color":color,"intensity":intensity}))
+            })
+            .collect::<Result<Vec<Value>, serde_json::Error>>()?;
+        let cpu_options = json!({
+            "budget":"workstation", "texture_filtering":true,
+            "progressive":{"samples_per_pixel":samples,"seed":4619},
+            "path":{"max_depth":64}, "primary_samples":1, "shadows":true,
+            "lights":[], "area_lights":area_lights,"area_samples":1,
+            "punctual_lights":lighting["punctual_lights"],
+            "environment":{"color":lighting["environment"],"intensity":1.0},
+            "aging":options["aging"], "denoise":false,
+            "output":{"tone_map":options["tone_map"],"linear_exr":true}
+        });
+        setup["job"] = json!({"method":"cpu_raytrace","transparent_background":false,"options":cpu_options});
+    } else {
+        setup["job"]["options"] = options;
+    }
+    let checked: RenderSetup = serde_json::from_value(setup.clone())?;
+    checked.validate()?;
+    require(checked.camera == master.camera, "reference camera differs from Master")?;
+    require(checked.surfaces == master.surfaces && checked.coats == master.coats, "reference lost surface maps or coats")?;
+    Ok(setup)
+}
+
+fn crease_audit(mesh: &MeshData) -> Result<Value, Box<dyn Error>> {
+    let positions: Vec<Vec3> = mesh.positions.as_chunks::<3>().0.iter().map(|p| Vec3::new(p[0], p[1], p[2])).collect();
+    let triangles = mesh.triangles.as_chunks::<3>().0;
+    let mut weld = std::collections::HashMap::new();
+    let mut canonical = Vec::with_capacity(positions.len());
+    for p in &positions {
+        let next = weld.len();
+        canonical.push(*weld.entry([(p.x + 0.0).to_bits(), (p.y + 0.0).to_bits(), (p.z + 0.0).to_bits()]).or_insert(next));
+    }
+    let mut edges = std::collections::HashMap::<(usize, usize), (usize, Option<usize>, usize)>::new();
+    let mut face_normals = Vec::with_capacity(triangles.len());
+    for (i, t) in triangles.iter().enumerate() {
+        let [a, b, c] = t.map(|k| positions.get(k as usize).copied());
+        let (Some(a), Some(b), Some(c)) = (a, b, c) else { return Err("audit index missing".into()) };
+        face_normals.push((b - a).cross(c - a).normalized().ok_or("audit triangle degenerate")?);
+        for k in 0..3 {
+            let (a, b) = (canonical[t[k] as usize], canonical[t[(k + 1) % 3] as usize]);
+            edges
+                .entry((a.min(b), a.max(b)))
+                .and_modify(|e| {
+                    e.1 = Some(i * 3 + k);
+                    e.2 += 1;
+                })
+                .or_insert((i * 3 + k, None, 1));
+        }
+    }
+    let normal = |corner: usize| -> Result<Vec3, Box<dyn Error>> {
+        let n = mesh.corner_normals.get(corner * 3..corner * 3 + 3).ok_or("audit normal missing")?;
+        Ok(Vec3::new(n[0], n[1], n[2]))
+    };
+    let mut bins = [0u64; 7];
+    let mut sharp = 0u64;
+    let mut sharp_discontinuous = 0u64;
+    let mut boundary_or_nonmanifold = 0u64;
+    for (_, (a, b, count)) in edges {
+        let Some(b) = b.filter(|_| count == 2) else {
+            boundary_or_nonmanifold += 1;
+            continue;
+        };
+        let angle = face_normals[a / 3].dot(face_normals[b / 3]).clamp(-1.0, 1.0).acos().to_degrees();
+        let bin = [1.0, 5.0, 10.0, 22.5, 45.0, 90.0].iter().position(|&max| angle <= max).unwrap_or(6);
+        bins[bin] += 1;
+        if angle > 10.0 + 1e-9 {
+            sharp += 1;
+            let (ak, bk) = (a % 3, b % 3);
+            let same_a = normal(a)?.dist(normal((b / 3) * 3 + (bk + 1) % 3)?) <= 1e-8;
+            let same_b = normal((a / 3) * 3 + (ak + 1) % 3)?.dist(normal(b)?) <= 1e-8;
+            if !same_a || !same_b {
+                sharp_discontinuous += 1;
+            }
+        }
+    }
+    Ok(json!({"manifold_edge_angle_bins_degrees":[[0,1],[1,5],[5,10],[10,22.5],[22.5,45],[45,90],[90,180]],
+        "manifold_edge_counts":bins,"geometric_sharp_edges_above_10_degrees_before":sharp,
+        "geometric_sharp_edges_above_10_degrees_after":sharp,"sharp_edges_with_shading_discontinuity":sharp_discontinuous,
+        "boundary_or_nonmanifold_edges":boundary_or_nonmanifold}))
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let mut args = std::env::args_os().skip(1);
+    let baseline = PathBuf::from(args.next().ok_or("usage: opus_quality_fixture BASELINE.sc NEW_OUTPUT_DIRECTORY")?);
+    let output = PathBuf::from(args.next().ok_or("missing new output directory")?);
+    require(args.next().is_none(), "unexpected argument")?;
+    fs::create_dir(&output)?;
+    let original = fs::read(&baseline)?;
+    let mut doc: Document = solidcraft_io::read_design(&original)?;
+    let master = doc.render.setups.get("OPUS Master").cloned().ok_or("missing OPUS Master")?;
+    require(master.surfaces.len() == 104 && master.optics.len() == 30 && master.coats.len() == 6, "fixture bindings differ from OPUS baseline")?;
+    require(doc.components.len() == 82 && doc.assembly.joints.len() == 81 && doc.assembly.links.len() == 15, "fixture assembly counts differ")?;
+    let baseline_doc = doc.clone();
+    let mut baseline_session = Session::new(doc.clone());
+    let baseline_scene = baseline_session.execute("render.scene", &json!({}))?;
+    require(scene_counts(&baseline_scene)? == (511, 729874), "baseline scene geometry counts differ")?;
+    let mut edits = Vec::new();
+    for feature in &mut doc.features {
+        if let FeatureKind::MeshImport { meshes, .. } = &mut feature.kind {
+            for mesh in meshes {
+                if CURVED.contains(&mesh.name.as_str()) {
+                    let positions = mesh.positions.clone();
+                    let triangles = mesh.triangles.clone();
+                    mesh.generate_crease_normals(10.0)?;
+                    require(
+                        Arc::ptr_eq(&positions, &mesh.positions) && Arc::ptr_eq(&triangles, &mesh.triangles),
+                        "normal generation changed geometry arrays",
+                    )?;
+                    edits.push(json!({"feature":feature.id,"body":mesh.name,"crease_angle_degrees":10.0,"triangles":mesh.triangles.len()/3,"normal_values":mesh.corner_normals.len(),"crease_audit":crease_audit(mesh)?}));
+                }
+            }
+        }
+    }
+    require(edits.len() == CURVED.len(), "a curated normal target is missing or duplicated")?;
+    doc.name = format!("{} — curated 10 degree shading reference", doc.name);
+    let mut session = Session::new(doc);
+    let mut setup_receipts = Vec::new();
+    for (cpu, pilot, name) in [
+        (true, false, "OPUS Physical CPU 4K"),
+        (false, false, "OPUS Physical GPU 4K"),
+        (true, true, "OPUS Physical CPU Pilot"),
+        (false, true, "OPUS Physical GPU Pilot"),
+    ] {
+        let setup = physical(&master, cpu, pilot)?;
+        setup_receipts.push(session.execute("render.settings.set", &json!({"name":name,"set":setup}))?);
+    }
+    require(session.doc.render.setups.get("OPUS Master") == Some(&master), "original Master setup changed")?;
+    let scene = session.execute("render.scene", &json!({}))?;
+    require(scene == baseline_scene, "shading changed captured geometry, names, bounds or stable targets")?;
+    require(
+        session.doc.components == baseline_doc.components
+            && session.doc.occurrences == baseline_doc.occurrences
+            && session.doc.assembly == baseline_doc.assembly,
+        "assembly, pose or occurrence metadata changed",
+    )?;
+    let copy_path = output.join("OPUS-04-physical-reference.sc");
+    let copy = solidcraft_io::write_design_container(&session.doc)?;
+    fs::write(&copy_path, &copy)?;
+    let reopened = solidcraft_io::read_design(&copy)?;
+    require(reopened == *session.doc, "copy changed on cold reopen")?;
+    fs::write(output.join("baseline-scene.json"), serde_json::to_vec_pretty(&baseline_scene)?)?;
+    fs::write(output.join("reference-setups.json"), serde_json::to_vec_pretty(&setup_receipts)?)?;
+    let report = json!({
+        "baseline":baseline,"reference":copy_path,"baseline_bytes":original.len(),"reference_bytes":copy.len(),
+        "geometry":{"bodies":511,"triangles":729874,"unchanged":true},
+        "assembly":{"components":82,"joints":81,"couplings":15,"unchanged":true},
+        "bindings_per_reference":{"surfaces":104,"optics":30,"coats":6,"aging":7,"area_lights":4,"punctual_lights":7},
+        "curated_normal_edits":edits,"master_unchanged":true,"camera_unchanged":true,
+        "assembly_and_saved_pose_unchanged":true,"recorded_motion_step15_applied":false,
+        "reference_shadow_transmission":false,"render_started":false,
+        "qualification":"fixture preparation and public settings/scene commands only; no transport convergence claim"
+    });
+    fs::write(output.join("fixture-manifest.json"), serde_json::to_vec_pretty(&report)?)?;
+    println!("{}", serde_json::to_string_pretty(&report)?);
+    Ok(())
+}

crates/engine/src/boolean_regression_tests.rs

@@ -1552,3 +1552,57 @@ fn join_that_meets_no_body_keeps_the_piece_and_says_so() {
     let combine = s.execute("solid.combine", &json!({"target": "A", "tools": ["B"], "operation": "join"})).unwrap();
     assert!(combine["warning"].is_null(), "{combine}");
 }
+
+/// #12996: a circular pattern of an untargeted cut made in a component, run with another
+/// component active, cuts the bodies of the cut's own component, as the cut did.
+#[test]
+fn pattern_of_an_untargeted_cut_in_a_component_works_with_root_active() {
+    let mut s = Session::default();
+    let run = |s: &mut Session, command: &str, params: Value| s.execute(command, &params).unwrap();
+    run(&mut s, "component.create", json!({"name": "Main Body"}));
+    run(&mut s, "sketch.create", json!({"plane": "XY"}));
+    run(&mut s, "sketch.rectangle.two_point", json!({"p0": [-50, -50], "p1": [50, 50]}));
+    run(&mut s, "sketch.finish", json!({}));
+    run(&mut s, "solid.extrude", json!({"distance": "20 mm", "operation": "new", "body_name": "Body1"}));
+    run(&mut s, "sketch.create", json!({"plane": {"origin": [0, 0, 20], "x_dir": [1, 0, 0], "y_dir": [0, 1, 0]}}));
+    run(&mut s, "sketch.circle.center", json!({"center": [30, 0], "radius": 4}));
+    run(&mut s, "sketch.finish", json!({}));
+    run(&mut s, "solid.extrude", json!({"distance": "10 mm", "direction": "negative", "operation": "cut", "name": "Extrude62"}));
+    let one_hole = volume(&s, "Body1");
+    run(&mut s, "component.activate", json!({"component": "root"}));
+    run(&mut s, "component.create", json!({"name": "Other"}));
+    run(&mut s, "solid.pattern.circular", json!({"features": ["Extrude62"], "axis": "Z", "count": 10}));
+    let hole = 10.0 * 16.0 * std::f64::consts::PI;
+    let got = volume(&s, "Body1");
+    assert!((one_hole - got - 9.0 * hole).abs() < 0.02 * hole, "{one_hole} -> {got}");
+}
+
+/// #12996: when the component active for the pattern has a body of its own, the copies of an
+/// untargeted cut keep cutting it, as they did before: saved designs rebuild the same.
+#[test]
+fn pattern_of_an_untargeted_cut_still_cuts_its_own_components_body() {
+    let mut s = Session::default();
+    let run = |s: &mut Session, command: &str, params: Value| s.execute(command, &params).unwrap();
+    run(&mut s, "component.create", json!({"name": "Main Body"}));
+    run(&mut s, "sketch.create", json!({"plane": "XY"}));
+    run(&mut s, "sketch.rectangle.two_point", json!({"p0": [-50, -50], "p1": [50, 50]}));
+    run(&mut s, "sketch.finish", json!({}));
+    run(&mut s, "solid.extrude", json!({"distance": "20 mm", "operation": "new", "body_name": "Body1"}));
+    run(&mut s, "sketch.create", json!({"plane": {"origin": [0, 0, 20], "x_dir": [1, 0, 0], "y_dir": [0, 1, 0]}}));
+    run(&mut s, "sketch.circle.center", json!({"center": [30, 0], "radius": 4}));
+    run(&mut s, "sketch.finish", json!({}));
+    run(&mut s, "solid.extrude", json!({"distance": "10 mm", "direction": "negative", "operation": "cut", "name": "Extrude62"}));
+    let one_hole = volume(&s, "Body1");
+    run(&mut s, "component.activate", json!({"component": "root"}));
+    run(&mut s, "component.create", json!({"name": "Other"}));
+    run(&mut s, "sketch.create", json!({"plane": "XY"}));
+    run(&mut s, "sketch.rectangle.two_point", json!({"p0": [-50, -50], "p1": [50, 50]}));
+    run(&mut s, "sketch.finish", json!({}));
+    run(&mut s, "solid.extrude", json!({"distance": "20 mm", "operation": "new", "body_name": "Plate2"}));
+    let plate = volume(&s, "Plate2");
+    run(&mut s, "solid.pattern.circular", json!({"features": ["Extrude62"], "axis": "Z", "count": 10}));
+    let hole = 10.0 * 16.0 * std::f64::consts::PI;
+    let (body1, plate2) = (volume(&s, "Body1"), volume(&s, "Plate2"));
+    assert!((one_hole - body1).abs() < 0.02 * hole, "Body1 untouched: {one_hole} -> {body1}");
+    assert!((plate - plate2 - 9.0 * hole).abs() < 0.02 * hole, "Plate2 cut: {plate} -> {plate2}");
+}

crates/engine/src/cmd/body_features.rs

@@ -0,0 +1,100 @@
+//! Which timeline features built each body (#11945): the data behind `model.body_features` and
+//! the Browser's optional features-under-bodies tree.
+
+use std::collections::{BTreeMap, HashMap, HashSet};
+
+use serde_json::Value;
+
+use crate::params::{bad, str_};
+use crate::schema::inspect::{BodyFeature, BodyFeatures, ModelBodyFeatures};
+use crate::{Result, Session};
+
+impl Session {
+    /// The features that built each body of the evaluated model, by the body's model name, in
+    /// timeline order: the feature that created it, every later feature that changed its
+    /// geometry, and the features of the bodies a feature consumed while it made or changed this
+    /// one (a Combine's tools, a body joined in). A piece a cut split off keeps the features of
+    /// the body it was cut from. Features behind the history marker, which built nothing yet,
+    /// are not listed.
+    ///
+    /// Decided on exact body identity (a body a feature passed through unchanged is the same
+    /// record), never on a mesh.
+    pub fn body_features(&self) -> BTreeMap<String, Vec<u64>> {
+        let order: HashMap<u64, usize> = self.doc.features.iter().enumerate().map(|(i, f)| (f.id, i)).collect();
+        // Each body before the feature being looked at: its geometry, its creator and its features.
+        let mut before: HashMap<String, (solidcraft_doc::kernel::Body, u64, Vec<u64>)> = HashMap::new();
+        for r in &self.model.results {
+            let id = r.id;
+            let after = &r.state.bodies;
+            let names: HashSet<&str> = after.iter().map(|b| b.name.as_str()).collect();
+            // What the feature consumed: bodies there before and gone after.
+            let consumed: Vec<u64> =
+                before.iter().filter(|(name, _)| !names.contains(name.as_str())).flat_map(|(_, (_, _, list))| list.iter().copied()).collect();
+            let mut next: HashMap<String, (solidcraft_doc::kernel::Body, u64, Vec<u64>)> = HashMap::with_capacity(after.len());
+            for b in after {
+                let list = match before.get(&b.name) {
+                    // Passed through unchanged.
+                    Some((old, creator, list)) if old.same(&b.body) && *creator == b.feature => list.clone(),
+                    // Changed: it keeps what built it so far.
+                    Some((_, creator, list)) if *creator == b.feature => touched(list.clone(), &consumed, id, &order),
+                    // Made by this feature.
+                    _ if b.feature == id => touched(Vec::new(), &consumed, id, &order),
+                    // A piece of a body made earlier (a split): what built the bodies of its creator.
+                    _ => {
+                        let inherited =
+                            before.values().filter(|(_, creator, _)| *creator == b.feature).flat_map(|(_, _, list)| list.iter().copied()).collect();
+                        touched(inherited, &consumed, id, &order)
+                    }
+                };
+                next.insert(b.name.clone(), (b.body.clone(), b.feature, list));
+            }
+            before = next;
+        }
+        // The model as it stands (a sketch shown live keeps its last results).
+        self.model
+            .state()
+            .bodies
+            .iter()
+            .map(|b| (b.name.clone(), before.get(&b.name).map(|(_, _, list)| list.clone()).unwrap_or_else(|| vec![b.feature])))
+            .collect()
+    }
+}
+
+/// `list` with the features of what was consumed and the feature `id` added, once each, in
+/// timeline order.
+fn touched(mut list: Vec<u64>, consumed: &[u64], id: u64, order: &HashMap<u64, usize>) -> Vec<u64> {
+    list.extend(consumed.iter().copied());
+    list.push(id);
+    list.sort_by_key(|f| order.get(f).copied().unwrap_or(usize::MAX));
+    list.dedup();
+    list
+}
+
+/// `model.body_features`: the features that built each body, or one body (a placed copy's name
+/// means the body it shows).
+pub(super) fn model_body_features(s: &mut Session, p: &Value) -> Result<Value> {
+    let cmd = "model.body_features";
+    let all = s.body_features();
+    let wanted = match str_(p, "body") {
+        Some(name) => {
+            let st = s.world_state()?;
+            let b = st.body(name).ok_or_else(|| bad(cmd, format!("no body `{name}`")))?;
+            Some((b.name.clone(), b.definition_name().to_string()))
+        }
+        None => None,
+    };
+    let feature = |id: &u64| BodyFeature { id: *id, name: s.doc.feature(*id).map(|f| f.name.clone()).unwrap_or_default() };
+    let bodies = match wanted {
+        Some((shown, definition)) => {
+            vec![BodyFeatures { body: shown, features: all.get(&definition).map(|l| l.iter().map(feature).collect()).unwrap_or_default() }]
+        }
+        None => s
+            .model
+            .state()
+            .bodies
+            .iter()
+            .map(|b| BodyFeatures { body: b.name.clone(), features: all.get(&b.name).map(|l| l.iter().map(feature).collect()).unwrap_or_default() })
+            .collect(),
+    };
+    serde_json::to_value(ModelBodyFeatures { bodies, param_warnings: Vec::new() }).map_err(|e| bad(cmd, e.to_string()))
+}

crates/engine/src/cmd/bom.rs

@@ -13,30 +13,45 @@
 
 use std::collections::{BTreeMap, HashSet};
 
-use serde_json::{Map, Value, json};
+use serde_json::{Value, json};
 use solidcraft_doc::BomType;
-use solidcraft_doc::metadata::{BOM_KEYS, BOM_TYPE, MAX_KEYS, Owner, check_text, key_list};
+use solidcraft_doc::metadata::{BOM_KEYS, BOM_TYPE, DESCRIPTION, MAX_KEYS, Owner, PART_NUMBER, REVISION, check_text, key_list};
 
 use super::CommandSpec;
 use crate::params::{bad, str_};
-use crate::schema::bom::{Bom, BomChild, BomParams, BomRow};
+use crate::schema::bom::{
+    Bom, BomChild, BomParams, BomRow, ComponentMetadataParams, ComponentMetadataResult, ComponentMetadataSetParams, ComponentMetadataSetResult,
+};
 use crate::schema::{TypedContract, output_schema_for};
 use crate::{EngineError, Result, Session};
 
 const BOM_CONTRACT: TypedContract<BomParams> = TypedContract::new();
+const METADATA_CONTRACT: TypedContract<ComponentMetadataParams> = TypedContract::new();
+const METADATA_SET_CONTRACT: TypedContract<ComponentMetadataSetParams> = TypedContract::new();
 
 pub static COMMANDS: &[CommandSpec] = &[
-    CommandSpec::new("component.metadata", "Part Properties", read).icon("settings").noundo().doc_only().params(
-        "component: id or name (0 or \"root\": the design's own properties) → component, name, part_number, description, revision, \
+    CommandSpec::new("component.metadata", "Part Properties", crate::checked!("component.metadata", read))
+        .icon("settings")
+        .noundo()
+        .doc_only()
+        .contract(&METADATA_CONTRACT)
+        .output(output_schema_for::<ComponentMetadataResult>)
+        .params(
+            "component: id or name (0 or \"root\": the design's own properties) → component, name, part_number, description, revision, \
          bom_type (components only), metadata (as saved, other tools' keys too), properties: {name: text}",
-    ),
-    CommandSpec::new("component.metadata.set", "Change Part Properties", set).icon("settings").doc_only().params(
-        "component: id or name (not the root: use document.metadata.set); part_number?, description?, revision?: text (empty or null \
+        ),
+    CommandSpec::new("component.metadata.set", "Change Part Properties", crate::checked!("component.metadata.set", set))
+        .icon("settings")
+        .doc_only()
+        .contract(&METADATA_SET_CONTRACT)
+        .output(output_schema_for::<ComponentMetadataSetResult>)
+        .params(
+            "component: id or name (not the root: use document.metadata.set); part_number?, description?, revision?: text (empty or null \
          removes); bom_type?: normal|phantom|reference|purchased|inseparable (empty or null: normal); values?: {key: value} \
          (SolidCraft's keys, as document.metadata's properties lists them, bom_type, or a reverse-DNS key holding an object); \
          properties?: {name: text, …} (free properties; empty or null removes). All or nothing, one undo step → component, \
          metadata, properties, changed: [keys]",
-    ),
+        ),
     CommandSpec::new("assembly.bom", "Bill of Materials", crate::checked!("assembly.bom", bom))
         .at("SOLID", "INSPECT")
         .icon("bom")
@@ -80,24 +95,25 @@ fn read(s: &mut Session, p: &Value) -> Result<Value> {
     let id = component_id(s, p, cmd)?;
     // The root is the design: its own properties, and no free ones.
     let (name, m, properties) = if id == 0 {
-        (&s.doc.name, &s.doc.metadata, json!({}))
+        (&s.doc.name, &s.doc.metadata, BTreeMap::new())
     } else {
         let c = s.doc.components.iter().find(|c| c.id == id).ok_or_else(|| bad(cmd, format!("no component `{id}`")))?;
-        (&c.name, &c.metadata, json!(c.properties))
+        (&c.name, &c.metadata, c.properties.clone())
     };
-    let mut out = Map::new();
-    out.insert("component".into(), json!(id));
-    out.insert("name".into(), json!(name));
-    for k in BOM_KEYS {
-        out.insert(k.to_string(), json!(m.text(k)));
-    }
-    // A bill of materials type is a component's; the design has none.
-    if id != 0 {
-        out.insert(BOM_TYPE.into(), json!(m.bom_type().as_str()));
-    }
-    out.insert("metadata".into(), json!(m));
-    out.insert("properties".into(), properties);
-    Ok(Value::Object(out))
+    let text = |k: &str| m.text(k).map(str::to_string);
+    let reply = ComponentMetadataResult {
+        component: id,
+        name: name.clone(),
+        part_number: text(PART_NUMBER),
+        description: text(DESCRIPTION),
+        revision: text(REVISION),
+        // A bill of materials type is a component's; the design has none.
+        bom_type: (id != 0).then(|| m.bom_type().as_str().to_string()),
+        metadata: m.0.clone(),
+        properties,
+        param_warnings: Vec::new(),
+    };
+    serde_json::to_value(reply).map_err(|e| bad(cmd, e.to_string()))
 }
 
 /// A free property as it may be saved (`None`: remove it), or why not.
@@ -178,8 +194,15 @@ fn set(s: &mut Session, p: &Value) -> Result<Value> {
         c.metadata = metadata;
         c.properties = properties;
     }
-    let c = s.doc.components.iter().find(|c| c.id == id);
-    Ok(json!({"component": id, "metadata": c.map(|c| &c.metadata), "properties": c.map(|c| &c.properties), "changed": changed}))
+    let c = s.doc.components.iter().find(|c| c.id == id).ok_or_else(|| bad(cmd, format!("no component `{id}`")))?;
+    let reply = ComponentMetadataSetResult {
+        component: id,
+        metadata: c.metadata.0.clone(),
+        properties: c.properties.clone(),
+        changed,
+        param_warnings: Vec::new(),
+    };
+    serde_json::to_value(reply).map_err(|e| bad(cmd, e.to_string()))
 }
 
 #[derive(Clone, Copy, PartialEq)]

crates/engine/src/cmd/browser.rs

@@ -19,9 +19,11 @@ use crate::params::{bad, bool_, expr, str_};
 use crate::schema::browser::{
     BodyRenameParams, BodyRenamed, BrowserFoldParams, BrowserFoldResult, BrowserGroupMade, BrowserGroupParams, BrowserGroupRenamed,
     BrowserMoveParams, BrowserMoved, BrowserOrderParams, BrowserOrdered, BrowserRenameGroupParams, BrowserUngroupParams, BrowserUngrouped,
-    BrowserVisibilityParams, BrowserVisibilityResult, DocumentUnitsParams, DocumentUnitsResult, Isolated, RepairDone, RepairFace, RepairHole,
-    RepairParams, RepairResult, RepairSewn, VisibilityState,
+    BrowserVisibilityParams, BrowserVisibilityResult, DocumentUnitsParams, DocumentUnitsResult, Isolated, PlaneFrame, RedefineAttachment,
+    RedefineSketchParams, RedefineSketchResult, RepairDone, RepairFace, RepairHole, RepairParams, RepairResult, RepairSewn, ViewApplyParams,
+    ViewDeleteParams, ViewDeleted, ViewListParams, ViewListResult, ViewRenameParams, ViewRenamed, ViewSaveParams, ViewSaved, VisibilityState,
 };
+use crate::schema::view_navigation::CameraReply;
 use crate::schema::{TypedContract, output_schema_for};
 use crate::{Result, Session};
 
@@ -35,6 +37,12 @@ const MOVE_CONTRACT: TypedContract<BrowserMoveParams> = TypedContract::new();
 const ORDER_CONTRACT: TypedContract<BrowserOrderParams> = TypedContract::new();
 const VISIBILITY_CONTRACT: TypedContract<BrowserVisibilityParams> = TypedContract::new();
 const FOLD_CONTRACT: TypedContract<BrowserFoldParams> = TypedContract::new();
+const REDEFINE_SKETCH_CONTRACT: TypedContract<RedefineSketchParams> = TypedContract::new();
+const VIEW_SAVE_CONTRACT: TypedContract<ViewSaveParams> = TypedContract::new();
+const VIEW_RENAME_CONTRACT: TypedContract<ViewRenameParams> = TypedContract::new();
+const VIEW_DELETE_CONTRACT: TypedContract<ViewDeleteParams> = TypedContract::new();
+const VIEW_LIST_CONTRACT: TypedContract<ViewListParams> = TypedContract::new();
+const VIEW_APPLY_CONTRACT: TypedContract<ViewApplyParams> = TypedContract::new();
 
 /// A reply as JSON: the commands here build their replies from the types their output schemas
 /// describe, so the two can't drift apart.
@@ -56,8 +64,10 @@ pub static COMMANDS: &[CommandSpec] = &[
         .params(
             "body: its name (a part the modelling kernel refuses, or an open part that should be a solid); gap?: expr (default 0.2 mm, at most 1 mm: free edges that pair up within it are sewn, each sewn edge carrying its own gap as its tolerance); patch_holes?: bool (default false: loops of free edges left are patched, in the plane of the faces around them where those are that plane, else tangent to them, and sewn in; otherwise the reply offers the patches); name? → the feature, and repair: what changed face by face (rebuilt and refused faces, sewn gaps, holes with their surface.patch), faces and largest edge tolerance before and after, closed, modelling, volume. Refused with why when nothing applies",
         ),
-    CommandSpec::new("sketch.redefine", "Redefine Sketch Plane", redefine_sketch)
+    CommandSpec::new("sketch.redefine", "Redefine Sketch Plane", crate::checked!("sketch.redefine", redefine_sketch))
         .icon("plane")
+        .contract(&REDEFINE_SKETCH_CONTRACT)
+        .output(output_schema_for::<RedefineSketchResult>)
         .params("sketch: id or name; plane: as sketch.create; frame?: as sketch.create; author_path?: exact owner occurrence ids; explicitly rebinds or freezes the plane while preserving geometry and dimension names"),
     CommandSpec::new("browser.group", "New Group", crate::checked!("browser.group", group))
         .icon("folder")
@@ -84,13 +94,33 @@ pub static COMMANDS: &[CommandSpec] = &[
         .contract(&UNITS_CONTRACT)
         .output(crate::schema::output_schema_for::<DocumentUnitsResult>)
         .params("units: mm|cm|m|in|ft (display and unit-less parameters; values keep their meaning)"),
-    CommandSpec::new("view.save", "New Named View", view_save)
+    CommandSpec::new("view.save", "New Named View", crate::checked!("view.save", view_save))
         .icon("camera")
+        .contract(&VIEW_SAVE_CONTRACT)
+        .output(output_schema_for::<ViewSaved>)
         .params("name?; camera: {target: [x,y,z], yaw, pitch, distance, fov?} (replaces a view of the same name)"),
-    CommandSpec::new("view.rename", "Rename Named View", view_rename).icon("rename").params("view: name, name"),
-    CommandSpec::new("view.delete", "Delete Named View", view_delete).icon("delete").params("view: name"),
-    CommandSpec::new("view.list", "List Named Views", view_list).icon("list").noundo().doc_only(),
-    CommandSpec::new("view.apply", "Restore Named View", view_apply).icon("camera").noundo().params(
+    CommandSpec::new("view.rename", "Rename Named View", crate::checked!("view.rename", view_rename))
+        .icon("rename")
+        .contract(&VIEW_RENAME_CONTRACT)
+        .output(output_schema_for::<ViewRenamed>)
+        .params("view: name, name"),
+    CommandSpec::new("view.delete", "Delete Named View", crate::checked!("view.delete", view_delete))
+        .icon("delete")
+        .contract(&VIEW_DELETE_CONTRACT)
+        .output(output_schema_for::<ViewDeleted>)
+        .params("view: name"),
+    CommandSpec::new("view.list", "List Named Views", crate::checked!("view.list", view_list))
+        .icon("list")
+        .noundo()
+        .contract(&VIEW_LIST_CONTRACT)
+        .output(output_schema_for::<ViewListResult>)
+        .doc_only(),
+    CommandSpec::new("view.apply", "Restore Named View", crate::checked!("view.apply", view_apply))
+        .icon("camera")
+        .noundo()
+        .contract(&VIEW_APPLY_CONTRACT)
+        .output(output_schema_for::<CameraReply>)
+        .params(
         "view?: front|back|top|bottom|left|right|iso|home (frames the model) | a named view's name; or camera?: {target: [x,y,z], yaw, pitch, distance, fov?, roll?} (radians, mm, about the up axis; yaw: heading of the line of sight, 0 along +Y (Front), π/2 along +X (Left), π (Back), −π/2 (Right); pitch: the eye's elevation, within ±π/2, π/2 = Top; roll defaults to 0, turns the picture clockwise, must be finite and is clamped to ±π; the View angles readout shows these in degrees; up is refused: the up axis comes from the design settings) → camera. The viewport (and the MCP screenshot) moves there. View state: not saved, not an undo step",
     ),
     CommandSpec::new("browser.order", "Order Browser Items", crate::checked!("browser.order", order))
@@ -1049,14 +1079,47 @@ fn document_units(s: &mut Session, p: &Value) -> Result<Value> {
     reply(kept)
 }
 
+/// A camera `view.save` keeps, as the handler reads it (and `ViewCamera`, its contract type): a
+/// [`solidcraft_doc::NamedView`] of finite numbers with a positive distance, or the message the
+/// handler refuses it with.
+pub(crate) fn saved_view_form(c: &Value) -> std::result::Result<solidcraft_doc::NamedView, String> {
+    let v: solidcraft_doc::NamedView = serde_json::from_value(c.clone()).map_err(|e| format!("bad camera: {e}"))?;
+    let ok = [v.target.x, v.target.y, v.target.z, v.yaw, v.pitch, v.distance, v.fov].iter().all(|x| x.is_finite()) && v.distance > 0.0;
+    if ok { Ok(v) } else { Err("the camera must be finite with a positive distance".into()) }
+}
+
+/// The camera `view.apply` turns to for a `camera` it is given, as the handler reads it (and
+/// `ApplyCamera`, its contract type), or the message the handler refuses it with.
+pub(crate) fn applied_camera_form(c: &Value) -> std::result::Result<crate::render::Camera, String> {
+    if c.get("up").is_some() {
+        return Err("camera `up` is not supported: the up axis comes from the design settings".into());
+    }
+    let roll = match c.get("roll") {
+        Some(value) => value.as_f64().filter(|r| r.is_finite()).ok_or("camera `roll` must be a finite number in radians")?,
+        None => 0.0,
+    };
+    let v: solidcraft_doc::NamedView = serde_json::from_value(c.clone()).map_err(|e| format!("bad camera: {e}"))?;
+    // Past a pole the same view has other angles; the orbit would snap it back (#6032).
+    if !(v.pitch.abs() <= std::f64::consts::FRAC_PI_2 + 1e-9) {
+        return Err("camera `pitch` must be within ±π/2 radians (±90°)".into());
+    }
+    let cam = crate::render::Camera { roll: roll.clamp(-std::f64::consts::PI, std::f64::consts::PI), ..camera_of(&v) };
+    if !usable_camera(&cam) {
+        return Err("the camera must be finite with a positive distance".into());
+    }
+    Ok(cam)
+}
+
+/// A camera the viewport can be put at: finite, with a positive distance and a field of view of
+/// at least 0.
+fn usable_camera(cam: &crate::render::Camera) -> bool {
+    cam.is_valid() && cam.fov.is_finite() && cam.fov >= 0.0
+}
+
 fn view_save(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "view.save";
     let c = p.get("camera").ok_or_else(|| bad(cmd, "`camera` is required"))?;
-    let mut v: solidcraft_doc::NamedView = serde_json::from_value(c.clone()).map_err(|e| bad(cmd, format!("bad camera: {e}")))?;
-    let ok = [v.target.x, v.target.y, v.target.z, v.yaw, v.pitch, v.distance, v.fov].iter().all(|x| x.is_finite()) && v.distance > 0.0;
-    if !ok {
-        return Err(bad(cmd, "the camera must be finite with a positive distance"));
-    }
+    let mut v = saved_view_form(c).map_err(|e| bad(cmd, e))?;
     let n = s.doc.named_views.len();
     v.name = match str_(p, "name").map(str::trim).filter(|n| !n.is_empty()) {
         Some(n) if n.len() <= 128 => n.to_string(),
@@ -1070,7 +1133,7 @@ fn view_save(s: &mut Session, p: &Value) -> Result<Value> {
     let d = s.doc_mut();
     d.named_views.retain(|x| x.name != name);
     d.named_views.push(v);
-    Ok(json!({ "view": name }))
+    reply(cmd, ViewSaved { view: name, param_warnings: Vec::new() })
 }
 
 fn view_apply(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1078,23 +1141,7 @@ fn view_apply(s: &mut Session, p: &Value) -> Result<Value> {
     let cam = match (str_(p, "view"), p.get("camera")) {
         (Some(_), Some(_)) => return Err(bad(cmd, "give `view` or `camera`, not both")),
         (None, None) => return Err(bad(cmd, "`view` (a name) or `camera` is required")),
-        (None, Some(c)) => {
-            if c.get("up").is_some() {
-                return Err(bad(cmd, "camera `up` is not supported: the up axis comes from the design settings"));
-            }
-            let roll = match c.get("roll") {
-                Some(value) => {
-                    value.as_f64().filter(|r| r.is_finite()).ok_or_else(|| bad(cmd, "camera `roll` must be a finite number in radians"))?
-                }
-                None => 0.0,
-            };
-            let v: solidcraft_doc::NamedView = serde_json::from_value(c.clone()).map_err(|e| bad(cmd, format!("bad camera: {e}")))?;
-            // Past a pole the same view has other angles; the orbit would snap it back (#6032).
-            if !(v.pitch.abs() <= std::f64::consts::FRAC_PI_2 + 1e-9) {
-                return Err(bad(cmd, "camera `pitch` must be within ±π/2 radians (±90°)"));
-            }
-            crate::render::Camera { roll: roll.clamp(-std::f64::consts::PI, std::f64::consts::PI), ..camera_of(&v) }
-        }
+        (None, Some(c)) => applied_camera_form(c).map_err(|e| bad(cmd, e))?,
         // Standard view names come first, as in the browser's Named Views folder.
         (Some(name), None) => match crate::render::StandardView::parse(name) {
             Some(sv) => {
@@ -1106,11 +1153,11 @@ fn view_apply(s: &mut Session, p: &Value) -> Result<Value> {
             None => s.doc.named_views.iter().find(|v| v.name == name).map(camera_of).ok_or_else(|| bad(cmd, format!("no named view `{name}`")))?,
         },
     };
-    if !cam.is_valid() || !cam.fov.is_finite() || cam.fov < 0.0 {
+    if !usable_camera(&cam) {
         return Err(bad(cmd, "the camera must be finite with a positive distance"));
     }
     s.camera = Some(cam);
-    Ok(json!({ "camera": cam }))
+    reply(cmd, CameraReply { camera: cam, param_warnings: Vec::new() })
 }
 
 /// The orbit camera of a named view (Z up, no roll).
@@ -1134,17 +1181,18 @@ fn view_rename(s: &mut Session, p: &Value) -> Result<Value> {
     if let Some(v) = s.doc_mut().named_views.get_mut(i) {
         v.name = name.to_string();
     }
-    Ok(json!({ "view": name }))
+    reply(cmd, ViewRenamed { view: name.to_string(), param_warnings: Vec::new() })
 }
 
 fn view_delete(s: &mut Session, p: &Value) -> Result<Value> {
-    let i = view_index(s, p, "view.delete")?;
+    let cmd = "view.delete";
+    let i = view_index(s, p, cmd)?;
     let v = s.doc_mut().named_views.remove(i);
-    Ok(json!({ "deleted": v.name }))
+    reply(cmd, ViewDeleted { deleted: v.name, param_warnings: Vec::new() })
 }
 
 fn view_list(s: &mut Session, _p: &Value) -> Result<Value> {
-    Ok(json!({ "views": s.doc.named_views }))
+    reply("view.list", ViewListResult { views: s.doc.named_views.clone(), param_warnings: Vec::new() })
 }
 
 /// The keys whose strings name bodies, alone or in a list (`body`, `targets`…), at any depth of a
@@ -1193,7 +1241,9 @@ fn repair_body(s: &mut Session, p: &Value) -> Result<Value> {
     use solidcraft_doc::expr::Kind;
     use solidcraft_kernel::{Continuity, SurfaceKind};
     let cmd = "body.repair";
-    let name = str_(p, "body").filter(|b| !b.trim().is_empty()).ok_or_else(|| bad(cmd, "`body` must name the part to repair"))?.to_string();
+    let name = str_(p, "body").filter(|b| !b.trim().is_empty()).ok_or_else(|| bad(cmd, "`body` must name the part to repair"))?;
+    // A placed copy's name means the body it shows (#9740); the repair goes on that body.
+    let name = s.own_body_name(name).ok_or_else(|| bad(cmd, format!("no body `{name}`")))?;
     let state = s.model.state();
     let source = state.body(&name).ok_or_else(|| bad(cmd, format!("no body `{name}`")))?;
     if source.body.is_mesh() {
@@ -1491,17 +1541,17 @@ fn redefine_sketch(s: &mut Session, p: &Value) -> Result<Value> {
 
     let attachment = s.doc.feature(id).and_then(|feature| match &feature.kind {
         FeatureKind::Sketch { plane, .. } => Some(if super::sketch::face::anchor(plane).is_some() {
-            "exact_face"
+            RedefineAttachment::ExactFace
         } else if solidcraft_doc::sheet::plane_sheet_face(plane).is_some() {
-            "sheet_face"
+            RedefineAttachment::SheetFace
         } else {
-            "fixed"
+            RedefineAttachment::Fixed
         }),
         _ => None,
     });
-    let mut out = json!({ "sketch": id,"attachment":attachment });
-    super::sketch::frame_reply(&mut out, frame, &placement);
-    Ok(out)
+    let note = frame.and_then(|f| super::sketch::frame_note(Some(f), &placement)).map(str::to_string);
+    let frame = frame.and_then(PlaneFrame::from_name);
+    reply(cmd, RedefineSketchResult { sketch: id, attachment, frame, note, created: None, param_warnings: Vec::new() })
 }
 
 #[cfg(test)]
@@ -1546,6 +1596,23 @@ mod tests {
         assert!(back.iter().any(|n| n == "KB") && back.iter().any(|n| n == "KB (K:2)"), "{back:?}");
     }
 
+    /// Repair takes a placed copy's name (`KB (K:2)`) for the body it shows, as Rename does.
+    #[test]
+    fn repair_part_takes_a_placed_copys_name() {
+        let mut s = Session::default();
+        run(&mut s, "component.create", json!({"name": "K"}));
+        run(&mut s, "solid.box", json!({"body_name": "KB", "length": 10, "width": 10, "height": 10}));
+        run(&mut s, "surface.unstitch", json!({"body": "KB", "faces": [[5, 5, 10]]}));
+        run(&mut s, "occurrence.copy", json!({"component": "K", "translate": [30, 0, 0]}));
+        assert!(s.model.state().body("KB").is_some_and(|b| b.body.is_surface()));
+        let features = s.doc.features.len();
+        run(&mut s, "body.repair", json!({"body": "KB (K:2)", "patch_holes": true}));
+        assert_eq!(s.doc.features.len(), features + 1);
+        assert!(s.model.state().body("KB").is_some_and(|b| !b.body.is_surface()), "the body both placements show is closed");
+        let err = s.execute("body.repair", &json!({"body": "KB (K:9)"})).unwrap_err().to_string();
+        assert!(err.contains("no body `KB (K:9)`"), "{err}");
+    }
+
     #[test]
     fn repair_part_patches_a_missing_face_as_one_undoable_feature() {
         let mut s = Session::default();

crates/engine/src/cmd/clipboard.rs

@@ -4,37 +4,70 @@
 
 use std::collections::BTreeMap;
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcraft_doc::{FeatureKind, PlaneRef};
 
 use super::CommandSpec;
 use crate::params::{bad, name_or_id_values, vec3};
+use crate::schema::timeline_clipboard::{CopyParams, CopyResult, PasteError, PasteParams, PasteResult, Pasted};
+use crate::schema::{TypedContract, output_schema_for};
 use crate::{Result, Session};
 
+const COPY_CONTRACT: TypedContract<CopyParams> = TypedContract::new();
+const PASTE_CONTRACT: TypedContract<PasteParams> = TypedContract::new();
+
 pub static COMMANDS: &[CommandSpec] = &[
-    CommandSpec::new("timeline.copy", "Copy Features", copy).icon("copy").noundo().params("features: [ids or names] (in timeline order on paste)"),
-    CommandSpec::new("timeline.paste", "Paste Features", paste).icon("paste").params(
-        "translate?: [x,y,z] (moves the copies' geometry); component?: where the copies go (default: the active one), \
+    CommandSpec::new("timeline.copy", "Copy Features", crate::checked!("timeline.copy", copy))
+        .icon("copy")
+        .noundo()
+        .contract(&COPY_CONTRACT)
+        .output(output_schema_for::<CopyResult>)
+        .params("features: [ids or names] (in timeline order on paste)"),
+    CommandSpec::new("timeline.paste", "Paste Features", crate::checked!("timeline.paste", paste))
+        .icon("paste")
+        .contract(&PASTE_CONTRACT)
+        .output(output_schema_for::<PasteResult>)
+        .params(
+            "translate?: [x,y,z] (moves the copies' geometry); component?: where the copies go (default: the active one), \
          component_path?: its placement (default: the active one, else its only one); the copies go at the marker, each where \
          its original is in the world (copies into their own component keep its coordinates); body transfers are left out; \
          from_design?: true to paste sketch features from the host's cross-design clipboard snapshot",
-    ),
+        ),
 ];
 
-fn copy(s: &mut Session, p: &Value) -> Result<Value> {
+/// A command's reply as JSON: they build their replies from the types their output schemas
+/// describe, so the two can't drift apart.
+fn reply(cmd: &str, reply: impl serde::Serialize) -> Result<Value> {
+    serde_json::to_value(reply).map_err(|e| bad(cmd, e.to_string()))
+}
+
+/// The `features` of `timeline.copy`: named or numbered, both kinds in one list, 1…1000 of them.
+/// The reader the command's contract uses too.
+pub(crate) fn copy_keys(p: &Value) -> Result<&[Value]> {
     let cmd = "timeline.copy";
-    // The features are named or numbered, and both kinds can sit in one list.
     let keys = name_or_id_values(cmd, p, "features")?;
     if keys.is_empty() || keys.len() > 1000 {
         return Err(bad(cmd, "`features` must list 1…1000 features"));
     }
+    Ok(keys)
+}
+
+/// A `component_path` of `timeline.paste`: 0 to 64 occurrence ids. The reader both pastes and the
+/// command's contract use.
+pub(crate) fn component_path_form(v: &Value) -> Option<Vec<u64>> {
+    v.as_array().filter(|a| a.len() <= 64).and_then(|a| a.iter().map(Value::as_u64).collect::<Option<Vec<_>>>())
+}
+
+fn copy(s: &mut Session, p: &Value) -> Result<Value> {
+    let cmd = "timeline.copy";
+    let keys = copy_keys(p)?;
     let ids = keys.iter().map(|key| super::edit::feature_id(s, Some(key), cmd)).collect::<Result<Vec<_>>>()?;
     // Keep timeline order so sketches come before the features that use them.
     let copied: Vec<solidcraft_doc::Feature> = s.doc.features.iter().filter(|f| ids.contains(&f.id)).cloned().collect();
     let names: Vec<String> = copied.iter().map(|f| f.name.clone()).collect();
     s.clipboard = copied;
     s.foreign_copy = Some(std::sync::Arc::new(crate::ForeignCopy::of_features(s)));
-    Ok(json!({"copied": names}))
+    reply(cmd, CopyResult { copied: names, param_warnings: Vec::new() })
 }
 
 /// Origin planes become explicit planes so a translation can move them.
@@ -86,12 +119,7 @@ fn paste(s: &mut Session, p: &Value) -> Result<Value> {
     };
     let given_path = match p.get("component_path") {
         None => None,
-        Some(v) => Some(
-            v.as_array()
-                .filter(|a| a.len() <= 64)
-                .and_then(|a| a.iter().map(Value::as_u64).collect::<Option<Vec<_>>>())
-                .ok_or_else(|| bad(cmd, "`component_path` must list 0..64 occurrence ids"))?,
-        ),
+        Some(v) => Some(component_path_form(v).ok_or_else(|| bad(cmd, "`component_path` must list 0..64 occurrence ids"))?),
     };
     let mut sketches: BTreeMap<u64, u64> = BTreeMap::new();
     let mut bodies: BTreeMap<String, String> = BTreeMap::new();
@@ -102,13 +130,14 @@ fn paste(s: &mut Session, p: &Value) -> Result<Value> {
     let author_path = match given_path {
         Some(path) => path,
         None if comp == s.active_component => s.active_occurrence_path.clone().unwrap_or_else(|| s.doc.first_path(comp)),
-        None => super::component::placing::placement_of(s, &s.placed_document(), comp, None, "component_path", cmd)?.0,
+        None => super::component::placing::placement_of(s, &s.design_document(), comp, None, "component_path", cmd)?.0,
     };
-    solidcraft_doc::EmbossFace::component_frame(&s.placed_document(), comp, &author_path)?;
+    solidcraft_doc::EmbossFace::component_frame(&s.design_document(), comp, &author_path)?;
     // A copy from another component goes where its original is in the world: its geometry moves
     // from its component's frame (its first placement, where its bodies have their own names)
-    // into the target's.
-    let placed = s.placed_document();
+    // into the target's. The design's placements: an exploded view shown is left out, or the copy
+    // would keep its offset once the view is closed.
+    let placed = s.design_document();
     let target_frame = placed.path_transform(comp, &author_path).ok_or_else(|| bad(cmd, "that path is not a placement of the target"))?;
     let to_target = solidcraft_doc::mat_inverse(&target_frame).ok_or_else(|| bad(cmd, "the target's frame is not invertible"))?;
     let frame_change: BTreeMap<u64, solidcraft_doc::Mat> = feats
@@ -229,15 +258,15 @@ fn paste(s: &mut Session, p: &Value) -> Result<Value> {
         let new_name = doc.feature(id).map(|x| x.name.clone()).unwrap_or_default();
         sketches.insert(f.id, id);
         names.insert(f.name.clone(), new_name.clone());
-        made.push(json!({"id": id, "name": new_name, "from": f.name}));
+        made.push(Pasted { id, name: new_name, from: f.name.clone() });
     }
     s.refresh();
-    let errors: Vec<Value> = made
+    let errors: Vec<PasteError> = made
         .iter()
-        .filter_map(|m| m["id"].as_u64())
-        .filter_map(|id| s.model.result(id).and_then(|r| r.error.clone()).map(|e| json!({"feature": id, "error": e})))
+        .map(|m| m.id)
+        .filter_map(|id| s.model.result(id).and_then(|r| r.error.clone()).map(|error| PasteError { feature: id, error }))
         .collect();
-    Ok(json!({"pasted": made, "errors": errors, "notices":notices}))
+    reply(cmd, PasteResult { pasted: made, errors, notices, param_warnings: Vec::new() })
 }
 
 #[cfg(test)]
@@ -373,6 +402,33 @@ mod tests {
         }
     }
 
+    /// A sketch pasted from another design while an exploded view moves the target is where the
+    /// original is once the target is shown assembled again.
+    #[test]
+    fn foreign_sketch_pasted_while_an_exploded_view_is_shown_keeps_its_world_position() {
+        let mut source = dimensioned_sketch();
+        run(&mut source, "timeline.copy", json!({"features": ["S"]}));
+        let mut target = Session::default();
+        let made = run(&mut target, "component.create", json!({"name": "Target", "activate": false}));
+        let component = made["component"].as_u64().unwrap();
+        let occurrence = made["occurrence"].as_u64().unwrap();
+        run(&mut target, "occurrence.ground", json!({"occurrence": occurrence, "grounded": false}));
+        run(&mut target, "occurrence.move", json!({"occurrence": occurrence, "translate": [100, 20, 30]}));
+        run(&mut target, "component.create", json!({"name": "B", "parent": 0, "activate": false}));
+        let view =
+            run(&mut target, "explode.create", json!({"moves": [{"occurrence": occurrence, "translate": [0, 0, 40]}]}))["view"].as_u64().unwrap();
+        run(&mut target, "explode.show", json!({"view": view}));
+        target.foreign_copy = source.foreign_copy.clone();
+        let id = run(&mut target, "timeline.paste", json!({"from_design": true, "component": component, "component_path": [occurrence]}))["pasted"]
+            [0]["id"]
+            .as_u64()
+            .unwrap();
+        run(&mut target, "explode.show", json!({}));
+        let original = source.world_state().unwrap().sketch(1).unwrap().plane;
+        let pasted = target.world_state().unwrap().sketch(id).unwrap().plane;
+        assert!(pasted.origin.dist(original.origin) < 1e-6, "{original:?} vs {pasted:?}");
+    }
+
     #[test]
     fn foreign_sketch_paste_refuses_external_references_and_bad_parameters_atomically() {
         let mut source = dimensioned_sketch();
@@ -496,6 +552,32 @@ mod tests {
         assert_eq!(s.doc.model_body_component(state.body("Block (2)").unwrap()), a);
     }
 
+    /// An exploded view shown while pasting is display only: once the design is shown assembled
+    /// again, the copy is where the original is, as it is without the view.
+    #[test]
+    fn features_pasted_while_an_exploded_view_is_shown_stay_where_they_were() {
+        let mut s = Session::default();
+        run(&mut s, "sketch.create", json!({"plane": "XY", "name": "S"}));
+        run(&mut s, "sketch.rectangle.two_point", json!({"p0": [0, 0], "p1": [10, 10]}));
+        run(&mut s, "sketch.finish", json!({}));
+        run(&mut s, "solid.extrude", json!({"sketch": "S", "distance": 5, "body_name": "Block"}));
+        let made = run(&mut s, "component.create", json!({"name": "A", "activate": false}));
+        let (a, at) = (made["component"].as_u64().unwrap(), made["occurrence"].as_u64().unwrap());
+        run(&mut s, "occurrence.ground", json!({"occurrence": at, "grounded": false}));
+        run(&mut s, "occurrence.move", json!({"occurrence": at, "translate": [100, 0, 0], "axis": [0, 0, 1], "angle": "90 deg"}));
+        // An exploded view needs two placements: B stays put.
+        run(&mut s, "component.create", json!({"name": "B", "parent": 0, "activate": false}));
+        let view = run(&mut s, "explode.create", json!({"moves": [{"occurrence": at, "translate": [0, 50, 0]}]}))["view"].as_u64().unwrap();
+        run(&mut s, "explode.show", json!({"view": view}));
+        run(&mut s, "timeline.copy", json!({"features": ["S", "Extrude1"]}));
+        let r = run(&mut s, "timeline.paste", json!({"component": a, "component_path": [at]}));
+        assert_eq!(r["errors"].as_array().map(Vec::len), Some(0), "{r}");
+        run(&mut s, "explode.show", json!({}));
+        let world = s.world_state().unwrap();
+        let (original, copy) = (world.body("Block").unwrap().mesh().bounds(), world.body("Block (2)").unwrap().mesh().bounds());
+        assert!(copy.min.dist(original.min) < 1e-6 && copy.max.dist(original.max) < 1e-6, "{original:?} vs {copy:?}");
+    }
+
     /// A sketch attached to a face of a body that isn't copied with it can't be carried into a
     /// component placed elsewhere: the paste is refused, saying to make its plane fixed first.
     #[test]

crates/engine/src/cmd/clipboard_foreign.rs

@@ -2,10 +2,11 @@
 
 use std::collections::{BTreeMap, BTreeSet};
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcraft_doc::{Document, Feature, FeatureKind, Mat, PlaneRef};
 
 use crate::params::{bad, vec3};
+use crate::schema::timeline_clipboard::{PasteResult, Pasted};
 use crate::{Result, Sel, Session};
 
 const CMD: &str = "timeline.paste";
@@ -186,15 +187,12 @@ pub(super) fn paste(s: &mut Session, p: &Value) -> Result<Value> {
         }
     };
     let path = match p.get("component_path") {
-        Some(v) => v
-            .as_array()
-            .filter(|a| a.len() <= 64)
-            .and_then(|a| a.iter().map(Value::as_u64).collect::<Option<Vec<_>>>())
-            .ok_or_else(|| bad(CMD, "`component_path` must list 0..64 occurrence ids"))?,
+        Some(v) => super::clipboard::component_path_form(v).ok_or_else(|| bad(CMD, "`component_path` must list 0..64 occurrence ids"))?,
         None if component == s.active_component => s.active_occurrence_path.clone().unwrap_or_else(|| s.doc.first_path(component)),
-        None => super::component::placing::placement_of(s, &s.placed_document(), component, None, "component_path", CMD)?.0,
+        None => super::component::placing::placement_of(s, &s.design_document(), component, None, "component_path", CMD)?.0,
     };
-    let placed = s.placed_document();
+    // The target as the design places it, without an exploded view shown.
+    let placed = s.design_document();
     let frame = placed.path_transform(component, &path).ok_or_else(|| bad(CMD, "that path is not a placement of the target"))?;
     let into_target = solidcraft_doc::mat_inverse(&frame).ok_or_else(|| bad(CMD, "the target's frame is not invertible"))?;
     drop(placed);
@@ -248,7 +246,7 @@ pub(super) fn paste(s: &mut Session, p: &Value) -> Result<Value> {
         }
         ids.insert(feature.id, id);
         names.insert(feature.name.clone(), name.clone());
-        made.push(json!({"id": id, "name": name, "from": feature.name}));
+        made.push(Pasted { id, name: name.clone(), from: feature.name.clone() });
     }
     parameters(scratch.doc_mut(), &copy.doc, &copy.features, &mut mapped)?;
     let source_values = copy.doc.param_values().0;
@@ -306,5 +304,6 @@ pub(super) fn paste(s: &mut Session, p: &Value) -> Result<Value> {
     }
     scratch.selection = ids.values().map(|id| Sel::Feature { id: *id }).collect();
     s.accept_computed(scratch);
-    Ok(json!({"pasted": made, "errors": [], "notices": []}))
+    serde_json::to_value(PasteResult { pasted: made, errors: Vec::new(), notices: Vec::new(), param_warnings: Vec::new() })
+        .map_err(|e| bad(CMD, e.to_string()))
 }

crates/engine/src/cmd/component.rs

@@ -13,17 +13,40 @@ use solidcraft_doc::{Feature, FeatureKind, Mat, Occurrence};
 use super::CommandSpec;
 use crate::params::{bad, bool_, str_, string_list, vec3};
 use crate::schema::component::{
-    EditInPlaceParams, EditInPlaceResult, FinishEditParams, FinishEditResult, MoveFeaturesParams, MoveFeaturesResult, MoveSketchesToPartsParams,
-    MoveSketchesToPartsResult, OccurrenceAlignParams, OccurrenceAlignResult, ReparentItemsParams, ReparentItemsResult,
+    ActivateParams, ActivateResult, CapturePositionParams, CapturePositionResult, ChildEntry, CompactPlacement, ComponentNode, CopyParams,
+    CopyResult, CreateParams, CreateResult, DeleteParams, DeleteResult, DragParams, DragResult, EditInPlaceParams, EditInPlaceResult,
+    FinishEditParams, FinishEditResult, FromBodiesParams, FromBodiesResult, GroundParams, GroundResult, ListParams, ListResult, MoveBodiesParams,
+    MoveBodiesResult, MoveFeaturesParams, MoveFeaturesResult, MoveParams, MoveResult, MoveSketchesParams, MoveSketchesResult,
+    MoveSketchesToPartsParams, MoveSketchesToPartsResult, NamesOrCount, OccurrenceAlignParams, OccurrenceAlignResult, OccurrencePropertiesParams,
+    OccurrencePropertiesResult, PasteNewParams, PasteNewResult, PlacementEntry, PlacementInfo, PropertiesParams, PropertiesResult, RenameParams,
+    RenameResult, ReparentItemsParams, ReparentItemsResult, RevertPositionParams, RevertPositionResult, UnlockParams, UnlockResult,
 };
 use crate::schema::{TypedContract, output_schema_for};
 use crate::{Result, Session};
 
+const ACTIVATE_CONTRACT: TypedContract<ActivateParams> = TypedContract::new();
+const CREATE_CONTRACT: TypedContract<CreateParams> = TypedContract::new();
+const DELETE_CONTRACT: TypedContract<DeleteParams> = TypedContract::new();
+const FROM_BODIES_CONTRACT: TypedContract<FromBodiesParams> = TypedContract::new();
+const LIST_CONTRACT: TypedContract<ListParams> = TypedContract::new();
+const PROPERTIES_CONTRACT: TypedContract<PropertiesParams> = TypedContract::new();
+const RENAME_CONTRACT: TypedContract<RenameParams> = TypedContract::new();
+const UNLOCK_CONTRACT: TypedContract<UnlockParams> = TypedContract::new();
 const EDIT_IN_PLACE_CONTRACT: TypedContract<EditInPlaceParams> = TypedContract::new();
 const FINISH_EDIT_CONTRACT: TypedContract<FinishEditParams> = TypedContract::new();
 const MOVE_FEATURES_CONTRACT: TypedContract<MoveFeaturesParams> = TypedContract::new();
 const MOVE_SKETCHES_TO_PARTS_CONTRACT: TypedContract<MoveSketchesToPartsParams> = TypedContract::new();
 const REPARENT_ITEMS_CONTRACT: TypedContract<ReparentItemsParams> = TypedContract::new();
+const CAPTURE_POSITION_CONTRACT: TypedContract<CapturePositionParams> = TypedContract::new();
+const COPY_CONTRACT: TypedContract<CopyParams> = TypedContract::new();
+const DRAG_CONTRACT: TypedContract<DragParams> = TypedContract::new();
+const GROUND_CONTRACT: TypedContract<GroundParams> = TypedContract::new();
+const MOVE_CONTRACT: TypedContract<MoveParams> = TypedContract::new();
+const MOVE_BODIES_CONTRACT: TypedContract<MoveBodiesParams> = TypedContract::new();
+const MOVE_SKETCHES_CONTRACT: TypedContract<MoveSketchesParams> = TypedContract::new();
+const OCCURRENCE_PROPERTIES_CONTRACT: TypedContract<OccurrencePropertiesParams> = TypedContract::new();
+const PASTE_NEW_CONTRACT: TypedContract<PasteNewParams> = TypedContract::new();
+const REVERT_POSITION_CONTRACT: TypedContract<RevertPositionParams> = TypedContract::new();
 
 #[path = "component_align.rs"]
 mod align;
@@ -67,14 +90,23 @@ pub static COMMANDS: &[CommandSpec] = &[
     CommandSpec::new("component.show_history", "Show Component History", show_history)
         .icon("eye").doc_only()
         .params("component: id or name; puts a component's features back in the History bar after Hide Component History (#10393)"),
-    CommandSpec::new("component.create", "New Component", new_component)
+    CommandSpec::new("component.create", "New Component", crate::checked!("component.create", new_component))
         .at("SOLID", "ASSEMBLE")
         .icon("component")
+        .contract(&CREATE_CONTRACT)
+        .output(output_schema_for::<CreateResult>)
         .params("name?, parent?: component id or name (default: the active one); parent_path?: exact parent placement; activate?: bool (default true); grounded?: bool (default: true for the design's first part, false otherwise)"),
-    CommandSpec::new("component.from_bodies", "Create Components from Bodies", from_bodies)
+    CommandSpec::new("component.from_bodies", "Create Components from Bodies", crate::checked!("component.from_bodies", from_bodies))
         .icon("component")
+        .contract(&FROM_BODIES_CONTRACT)
+        .output(output_schema_for::<FromBodiesResult>)
         .params("bodies: [names] → one new component per body, named after it"),
-    CommandSpec::new("component.activate", "Activate Component", activate).icon("activate").noundo().params("component: id or name (0 or \"root\" for the design); occurrence?, path?: exact placement used to author shared geometry"),
+    CommandSpec::new("component.activate", "Activate Component", crate::checked!("component.activate", activate))
+        .icon("activate")
+        .noundo()
+        .contract(&ACTIVATE_CONTRACT)
+        .output(output_schema_for::<ActivateResult>)
+        .params("component: id or name (0 or \"root\" for the design); occurrence?, path?: exact placement used to author shared geometry"),
     CommandSpec::new("component.edit_in_place", "Edit in Place", crate::checked!("component.edit_in_place", edit_in_place))
         .icon("edit")
         .noundo()
@@ -99,23 +131,48 @@ pub static COMMANDS: &[CommandSpec] = &[
              fails while the design has unsaved changes (run file.save first) or something is open in it; asked during the agent's \
              turn it finishes once the turn ends (queued: true); elsewhere nothing changes",
         ),
-    CommandSpec::new("component.list", "List Components", list).icon("list").noundo().params(
-        "compact?: bool (counts of bodies, features, sketches and construction planes instead of their names; occurrences leave out \
-         identity transforms; children as occurrence ids); bodies?: bool (with compact: body names, not their count)",
-    ),
-    CommandSpec::new("component.properties", "Component Physical Properties", properties::component)
+    CommandSpec::new("component.list", "List Components", crate::checked!("component.list", list))
+        .icon("list")
+        .noundo()
+        .contract(&LIST_CONTRACT)
+        .output(output_schema_for::<ListResult>)
+        .params(
+            "compact?: bool (counts of bodies, features, sketches and construction planes instead of their names; occurrences leave out \
+             identity transforms; children as occurrence ids); bodies?: bool (with compact: body names, not their count)",
+        ),
+    CommandSpec::new("component.properties", "Component Physical Properties", crate::checked!("component.properties", properties::component))
         .icon("measure").noundo()
+        .contract(&PROPERTIES_CONTRACT)
+        .output(output_schema_for::<PropertiesResult>)
         .params("component?: id or name (default active); descendants?: bool (default true); about?: [x, y, z] (mm). Measures the first placement, or all placements for root, including pending moves; material-aware mass and center of mass in world coordinates; volume, density, mass, center of mass and inertia_g_mm2 (the inertia tensor about the body's center of mass, world axes, from its tessellation) only for closed, consistently oriented bodies; total.open_bodies_skipped counts open bodies excluded from volume/mass totals; total.first_moment_g_mm (mass × center of mass), inertia_g_mm2 about the total center of mass, principal_moments_g_mm2 (smallest first) and principal_axes (unit, right-handed); with about, total.inertia_about {point, inertia_g_mm2}"),
-    CommandSpec::new("occurrence.properties", "Occurrence Physical Properties", properties::occurrence)
+    CommandSpec::new("occurrence.properties", "Occurrence Physical Properties", crate::checked!("occurrence.properties", properties::occurrence))
         .icon("measure").noundo()
+        .contract(&OCCURRENCE_PROPERTIES_CONTRACT)
+        .output(output_schema_for::<OccurrencePropertiesResult>)
         .params("occurrence: id or name; path?: [occurrence ids] (required if nested under multiple instances); descendants?: bool (default true); about?: [x, y, z] (mm). Physical properties of this placement in world coordinates, including pending moves; volume, density, mass, center of mass and inertia_g_mm2 only for closed, consistently oriented bodies; total.open_bodies_skipped counts open bodies excluded from volume/mass totals; total inertia as in component.properties"),
-    CommandSpec::new("component.rename", "Rename Component", rename).icon("rename").params("component, name"),
-    CommandSpec::new("component.delete", "Delete Component", delete).icon("delete").params("component: deletes it, its subcomponents, occurrences and features"),
-    CommandSpec::new("component.unlock", "Unlock Contents", unlock).icon("rigid_group").params(
-        "component: removes the rigid joints that hold its contents together (an imported assembly's rigid group), so its parts \
-         move and take joints one by one → joints (the ids removed)",
-    ),
-    CommandSpec::new("component.move_bodies", "Move Bodies to Component", move_bodies).icon("move").params(
+    CommandSpec::new("component.rename", "Rename Component", crate::checked!("component.rename", rename))
+        .icon("rename")
+        .contract(&RENAME_CONTRACT)
+        .output(output_schema_for::<RenameResult>)
+        .params("component, name"),
+    CommandSpec::new("component.delete", "Delete Component", crate::checked!("component.delete", delete))
+        .icon("delete")
+        .contract(&DELETE_CONTRACT)
+        .output(output_schema_for::<DeleteResult>)
+        .params("component: deletes it, its subcomponents, occurrences and features"),
+    CommandSpec::new("component.unlock", "Unlock Contents", crate::checked!("component.unlock", unlock))
+        .icon("rigid_group")
+        .contract(&UNLOCK_CONTRACT)
+        .output(output_schema_for::<UnlockResult>)
+        .params(
+            "component: removes the rigid joints that hold its contents together (an imported assembly's rigid group), so its parts \
+             move and take joints one by one → joints (the ids removed)",
+        ),
+    CommandSpec::new("component.move_bodies", "Move Bodies to Component", crate::checked!("component.move_bodies", move_bodies))
+        .icon("move")
+        .contract(&MOVE_BODIES_CONTRACT)
+        .output(output_schema_for::<MoveBodiesResult>)
+        .params(
         "bodies: [names], component; component_path?: its placement to place them by (default: its only one, else the active \
          one; a component placed more than once gets them in every instance); from_path?: the placement of their component they \
          move from (default: its only one, else its first, where its bodies have their own names)",
@@ -134,8 +191,10 @@ pub static COMMANDS: &[CommandSpec] = &[
          A component that uses what isn't in it (another body, sketch or parameter) is refused, saying what. Returns \
          `bodies` and `feature`, or the pasted components' `paths`",
     ),
-    CommandSpec::new("component.move_sketches", "Move Sketches to Component", move_sketches)
+    CommandSpec::new("component.move_sketches", "Move Sketches to Component", crate::checked!("component.move_sketches", move_sketches))
         .icon("move")
+        .contract(&MOVE_SKETCHES_CONTRACT)
+        .output(output_schema_for::<MoveSketchesResult>)
         .params("sketches: [ids or names], component; the sketches keep their own coordinates (component.move_features keeps them where they are in the world), except that a sketch on an exactly attached face stays where it is on the face"),
     CommandSpec::new(
         "component.move_sketches.to_parts",
@@ -171,12 +230,26 @@ pub static COMMANDS: &[CommandSpec] = &[
              nothing: placements move first (taking what they hold), then features (taking the bodies they made), then the bodies \
              still elsewhere (a body transfer, which leaves its features behind)",
         ),
-    CommandSpec::new("occurrence.copy", "Paste (Instance)", copy_occurrence).icon("copy")
+    CommandSpec::new("occurrence.copy", "Paste (Instance)", crate::checked!("occurrence.copy", copy_occurrence))
+        .icon("copy")
+        .contract(&COPY_CONTRACT)
+        .output(output_schema_for::<CopyResult>)
         .params("component (or occurrence): what to place again; path?: validates selected occurrence; parent?: component (default: the same parent); translate?: [x,y,z]; in_place?: bool (default false: the selected transform within the parent; true: where the selected placement is in the world, translate in world axes; a parent placed more than once is placed by parent_path?, else the active placement, and every instance gets the copy). Copies the selected effective transform, including pending moves"),
-    CommandSpec::new("component.paste_new", "Paste New", paste_new).icon("paste").params("component: independently copy its nested definition graph and history, materials and styles; occurrence?, path?: selected source placement; parent?: component the copy goes in (default: the source placement's; not the component or one inside it); in_place?, parent_path?: as occurrence.copy; translate?: [x,y,z]. Reassigned external bodies become base geometry; retained external links and omitted boundary joints are reported"),
-    CommandSpec::new("occurrence.move", "Move Occurrence", move_occurrence).icon("move")
+    CommandSpec::new("component.paste_new", "Paste New", crate::checked!("component.paste_new", paste_new))
+        .icon("paste")
+        .contract(&PASTE_NEW_CONTRACT)
+        .output(output_schema_for::<PasteNewResult>)
+        .params("component: independently copy its nested definition graph and history, materials and styles; occurrence?, path?: selected source placement; parent?: component the copy goes in (default: the source placement's; not the component or one inside it); in_place?, parent_path?: as occurrence.copy; translate?: [x,y,z]. Reassigned external bodies become base geometry; retained external links and omitted boundary joints are reported"),
+    CommandSpec::new("occurrence.move", "Move Occurrence", crate::checked!("occurrence.move", move_occurrence))
+        .icon("move")
+        .contract(&MOVE_CONTRACT)
+        .output(output_schema_for::<MoveResult>)
         .params("occurrence; path?: exact placement; space?: local|world (default local); translate?: [x,y,z]; axis?: [x,y,z], angle?: radians or \"30 deg\", origin?: [x,y,z]; matrix?: [12 or 16 numbers] (instead of translate/axis/angle/origin: a rigid move as a row-major 3x4 rotation-and-translation or 4x4 matrix, flat or as rows; one that is a rotation only up to rounding is orthonormalised, a scale, shear or mirror is refused); tolerance?: largest accepted |RᵀR − I| (default 1e-9, at most 1e-3); capture?: bool (default true; false keeps it pending until Capture Position); move_grounded?: bool (default false: a grounded occurrence refuses; true moves it and it stays grounded). Nested occurrence definitions remain shared. Replies {occurrence, transform, pending}; when joints hold it to something fixed and put it back, transform is where it is and the reply adds reverted: true and a warning naming the joint"),
-    CommandSpec::new("occurrence.drag", "Drag Occurrence", drag::drag).icon("move").params(
+    CommandSpec::new("occurrence.drag", "Drag Occurrence", crate::checked!("occurrence.drag", drag::drag))
+        .icon("move")
+        .contract(&DRAG_CONTRACT)
+        .output(output_schema_for::<DragResult>)
+        .params(
         "occurrence or path: exact placement; at: [x,y,z] world point on it; point: [x,y,z] where it goes. Moves the placement by \
          point - at (with any chain of joints it is in that is joined to nothing grounded) and captures its position; other pending \
          moves stay pending. Shared definitions move in all placements. Grounded parts and parts joints hold to something fixed are refused (joint.reach moves those)",
@@ -191,18 +264,38 @@ pub static COMMANDS: &[CommandSpec] = &[
              world coordinates without changing shared component geometry; a placement inside a component placed more than once moves in \
              every placement of it, and the reply's `shared` lists those paths",
         ),
-    CommandSpec::new("occurrence.ground", "Ground", ground).icon("ground").params("occurrence; grounded?: bool (default toggles)"),
+    CommandSpec::new("occurrence.ground", "Ground", crate::checked!("occurrence.ground", ground))
+        .icon("ground")
+        .contract(&GROUND_CONTRACT)
+        .output(output_schema_for::<GroundResult>)
+        .params("occurrence; grounded?: bool (default toggles)"),
     CommandSpec::new("occurrence.reparent", "Move to Component", reparent::reparent).icon("move").params(
         "occurrence; path?: exact placement; parent: component id or name (0 or \"root\" for the design); parent_path?: the parent's \
          placement to place it by (default: its only one, else the active one; every instance of the parent gets it). The placement \
          keeps its world position; a move that would break a feature is refused",
     ),
-    CommandSpec::new("component.capture_position", "Capture Position", capture).at("SOLID", "POSITION").icon("capture").params("keeps pending occurrence moves"),
-    CommandSpec::new("component.revert_position", "Revert Position", revert).at("SOLID", "POSITION").icon("revert").noundo().params("occurrences?: [ids] (default all); drops selected pending occurrence moves"),
+    CommandSpec::new("component.capture_position", "Capture Position", crate::checked!("component.capture_position", capture))
+        .at("SOLID", "POSITION")
+        .icon("capture")
+        .contract(&CAPTURE_POSITION_CONTRACT)
+        .output(output_schema_for::<CapturePositionResult>)
+        .params("keeps pending occurrence moves"),
+    CommandSpec::new("component.revert_position", "Revert Position", crate::checked!("component.revert_position", revert))
+        .at("SOLID", "POSITION")
+        .icon("revert")
+        .noundo()
+        .contract(&REVERT_POSITION_CONTRACT)
+        .output(output_schema_for::<RevertPositionResult>)
+        .params("occurrences?: [ids] (default all); drops selected pending occurrence moves"),
 ];
 
 const ALIGN_CONTRACT: TypedContract<OccurrenceAlignParams> = TypedContract::new();
 
+/// A typed reply as the JSON a handler returns.
+pub(super) fn reply<T: serde::Serialize>(value: T) -> Result<Value> {
+    serde_json::to_value(value).map_err(|e| crate::EngineError::Other(e.to_string()))
+}
+
 fn key(v: Option<&Value>) -> Option<String> {
     match v {
         Some(Value::Number(n)) => Some(n.to_string()),
@@ -225,7 +318,7 @@ fn translation(t: Vec3) -> Mat {
     solidcraft_doc::rigid(t, Vec3::ZERO, Vec3::Z, 0.0)
 }
 
-fn move_vector(p: &Value, key: &str, default: Vec3, coordinate: bool, cmd: &str) -> Result<Vec3> {
+pub(crate) fn move_vector(p: &Value, key: &str, default: Vec3, coordinate: bool, cmd: &str) -> Result<Vec3> {
     let v = match p.get(key) {
         None => default,
         Some(value) => vec3(value).ok_or_else(|| bad(cmd, format!("{key} must contain three finite numbers")))?,
@@ -288,7 +381,14 @@ pub(super) fn new_component(s: &mut Session, p: &Value) -> Result<Value> {
     }
     let name = s.doc.components.iter().find(|c| c.id == id).map(|c| c.name.clone()).unwrap_or_default();
     let occ = s.doc.occurrence_of(id);
-    Ok(json!({"component": id, "name": name, "parent": parent, "occurrence": occ.map(|o| o.id), "grounded": occ.is_some_and(|o| o.grounded)}))
+    reply(CreateResult {
+        component: id,
+        name,
+        parent,
+        occurrence: occ.map(|o| o.id),
+        grounded: occ.is_some_and(|o| o.grounded),
+        param_warnings: Vec::new(),
+    })
 }
 
 fn from_bodies(s: &mut Session, p: &Value) -> Result<Value> {
@@ -334,7 +434,7 @@ fn activate(s: &mut Session, p: &Value) -> Result<Value> {
     s.active_component = id;
     s.active_occurrence_path = path;
     s.revision += 1;
-    Ok(json!({ "active": id }))
+    reply(ActivateResult { active: id, param_warnings: Vec::new() })
 }
 
 fn list(s: &mut Session, p: &Value) -> Result<Value> {
@@ -342,17 +442,20 @@ fn list(s: &mut Session, p: &Value) -> Result<Value> {
     let doc = &s.doc;
     // Compact: what a large assembly needs to be found around in, without every name and matrix.
     let compact = bool_(p, "compact").unwrap_or(false);
-    let names = |v: Vec<&str>| if compact { json!(v.len()) } else { json!(v) };
+    let names = |v: Vec<&str>| if compact { NamesOrCount::Count(v.len()) } else { NamesOrCount::Names(v.into_iter().map(str::to_string).collect()) };
     let body_names = !compact || bool_(p, "bodies").unwrap_or(false);
     let placement = |o: &Occurrence| {
         if !compact {
-            return json!(o);
+            return PlacementEntry::Full(PlacementInfo::from(o));
         }
-        let mut v = json!({"id": o.id, "name": o.name, "parent": o.parent, "grounded": o.grounded});
-        if o.transform.iter().flatten().zip(solidcraft_doc::IDENTITY.iter().flatten()).any(|(a, b)| (a - b).abs() > 1e-12) {
-            v["transform"] = json!(o.transform);
-        }
-        v
+        let moved = o.transform.iter().flatten().zip(solidcraft_doc::IDENTITY.iter().flatten()).any(|(a, b)| (a - b).abs() > 1e-12);
+        PlacementEntry::Compact(CompactPlacement {
+            id: o.id,
+            name: o.name.clone(),
+            parent: o.parent,
+            grounded: o.grounded,
+            transform: moved.then_some(o.transform),
+        })
     };
     // Each component's bodies, features, occurrences and children, grouped once rather than
     // searched for every component (thousands of each in a design with many components).
@@ -376,17 +479,37 @@ fn list(s: &mut Session, p: &Value) -> Result<Value> {
         let sketches = named(|k| matches!(k, FeatureKind::Sketch { .. }));
         let construction = named(|k| matches!(k, FeatureKind::ConstructionPlane { .. }));
         let features = named(|k| !matches!(k, FeatureKind::Sketch { .. } | FeatureKind::ConstructionPlane { .. }));
-        let occurrences: Vec<Value> = occurrences_of.get(&id).into_iter().flatten().map(|o| placement(o)).collect();
-        let children: Vec<Value> = children_of.get(&id).into_iter().flatten().map(|o| if compact { json!(o.id) } else { json!(o) }).collect();
-        let bodies = if body_names { json!(bodies) } else { json!(bodies.len()) };
-        json!({"id": id, "name": name, "parent": parent, "bodies": bodies, "features": names(features), "sketches": names(sketches),
-            "construction": names(construction), "occurrences": occurrences, "children": children})
+        let occurrences: Vec<PlacementEntry> = occurrences_of.get(&id).into_iter().flatten().map(|o| placement(o)).collect();
+        let children: Vec<ChildEntry> = children_of
+            .get(&id)
+            .into_iter()
+            .flatten()
+            .map(|o| if compact { ChildEntry::Id(o.id) } else { ChildEntry::Full(PlacementInfo::from(*o)) })
+            .collect();
+        let bodies =
+            if body_names { NamesOrCount::Names(bodies.into_iter().map(str::to_string).collect()) } else { NamesOrCount::Count(bodies.len()) };
+        ComponentNode {
+            id,
+            name: name.to_string(),
+            parent,
+            bodies,
+            features: names(features),
+            sketches: names(sketches),
+            construction: names(construction),
+            occurrences,
+            children,
+        }
     };
     let mut out = vec![node(0, &doc.name, None)];
     for c in &doc.components {
         out.push(node(c.id, &c.name, Some(c.parent)));
     }
-    Ok(json!({"active": s.active_component, "components": out, "pending_moves": s.pending_moves.keys().collect::<Vec<_>>()}))
+    reply(ListResult {
+        active: s.active_component,
+        components: out,
+        pending_moves: s.pending_moves.keys().copied().collect(),
+        param_warnings: Vec::new(),
+    })
 }
 
 fn rename(s: &mut Session, p: &Value) -> Result<Value> {
@@ -411,7 +534,7 @@ fn rename(s: &mut Session, p: &Value) -> Result<Value> {
         // A sketch projecting a body of one of those placements keeps it.
         super::sketch_project::follow_placed_renames(d, &st, &placed, None);
     }
-    Ok(json!({"component": id, "name": name}))
+    reply(RenameResult { component: id, name: name.to_string(), param_warnings: Vec::new() })
 }
 
 fn delete(s: &mut Session, p: &Value) -> Result<Value> {
@@ -428,7 +551,7 @@ fn delete(s: &mut Session, p: &Value) -> Result<Value> {
     if gone.contains(&s.active_component) {
         s.active_component = 0;
     }
-    Ok(json!({"deleted": gone, "features": removed.features}))
+    reply(DeleteResult { deleted: gone, features: removed.features, param_warnings: Vec::new() })
 }
 
 fn unlock(s: &mut Session, p: &Value) -> Result<Value> {
@@ -448,7 +571,7 @@ fn unlock(s: &mut Session, p: &Value) -> Result<Value> {
     }
     doc.assembly.links.retain(|l| !gone.contains(&l.a) && !gone.contains(&l.b));
     s.visibility.hidden_joints.retain(|h| !gone.contains(h));
-    Ok(json!({"component": id, "joints": gone}))
+    reply(UnlockResult { component: id, joints: gone, param_warnings: Vec::new() })
 }
 
 fn move_bodies(s: &mut Session, p: &Value) -> Result<Value> {
@@ -547,7 +670,7 @@ fn move_sketches(s: &mut Session, p: &Value) -> Result<Value> {
             f.component = to;
         }
     }
-    Ok(json!({"sketches": ids, "component": to}))
+    reply(MoveSketchesResult { sketches: ids, component: to, param_warnings: Vec::new() })
 }
 
 pub(super) fn copy_occurrence(s: &mut Session, p: &Value) -> Result<Value> {
@@ -581,7 +704,7 @@ pub(super) fn copy_occurrence(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad(cmd, "copy transform exceeds supported numeric range"));
     }
     let id = s.doc_mut().add_occurrence(comp, parent, m)?;
-    Ok(json!({"occurrence": id, "component": comp}))
+    reply(CopyResult { occurrence: id, component: comp, param_warnings: Vec::new() })
 }
 
 fn paste_new(s: &mut Session, p: &Value) -> Result<Value> {
@@ -711,17 +834,7 @@ fn move_occurrence(s: &mut Session, p: &Value) -> Result<Value> {
         delta
     };
     let cur = if let Some(value) = p.get("base_transform") {
-        let base: Mat = serde_json::from_value(value.clone()).map_err(|_| bad(cmd, "base_transform must be a 4x4 affine matrix"))?;
-        if !valid_position(&base)
-            || base[0][3].abs() > 1e-12
-            || base[1][3].abs() > 1e-12
-            || base[2][3].abs() > 1e-12
-            || (base[3][3] - 1.0).abs() > 1e-12
-            || solidcraft_doc::mat_inverse(&base).is_none()
-        {
-            return Err(bad(cmd, "base_transform must be finite, affine and invertible"));
-        }
-        base
+        base_transform(value).map_err(|message| bad(cmd, message))?
     } else {
         s.uncaptured_moves().get(&id).copied().unwrap_or(o.transform)
     };
@@ -735,24 +848,47 @@ fn move_occurrence(s: &mut Session, p: &Value) -> Result<Value> {
             x.transform = next;
         }
         if !s.doc.assembly.joints.is_empty() {
-            return Ok(after_joints(s, p, id, next, cmd));
+            return reply(after_joints(s, p, id, next, cmd));
         }
     } else {
         s.pending_moves.insert(id, next);
         s.revision += 1;
     }
-    Ok(json!({"occurrence": id, "transform": next, "pending": !bool_(p, "capture").unwrap_or(true)}))
+    reply(MoveResult {
+        occurrence: id,
+        transform: next,
+        pending: !bool_(p, "capture").unwrap_or(true),
+        reverted: false,
+        warning: None,
+        param_warnings: Vec::new(),
+    })
+}
+
+/// A move's `base_transform`: a 4×4 matrix that is finite, affine and invertible, or what is
+/// wrong with it. The parameters contract reads it the same way.
+pub(crate) fn base_transform(value: &Value) -> std::result::Result<Mat, &'static str> {
+    let base: Mat = serde_json::from_value(value.clone()).map_err(|_| "base_transform must be a 4x4 affine matrix")?;
+    if !valid_position(&base)
+        || base[0][3].abs() > 1e-12
+        || base[1][3].abs() > 1e-12
+        || base[2][3].abs() > 1e-12
+        || (base[3][3] - 1.0).abs() > 1e-12
+        || solidcraft_doc::mat_inverse(&base).is_none()
+    {
+        return Err("base_transform must be finite, affine and invertible");
+    }
+    Ok(base)
 }
 
 /// The reply to a captured move once the joints are solved (#11723): a part its joints hold to
 /// something fixed is put back by that solve, so the reply gives where it is now, says
 /// `reverted`, and names the joint and what to change instead.
-fn after_joints(s: &mut Session, p: &Value, id: u64, moved: Mat, cmd: &str) -> Value {
+fn after_joints(s: &mut Session, p: &Value, id: u64, moved: Mat, cmd: &str) -> MoveResult {
     s.refresh();
     let now = s.doc.occurrences.iter().find(|o| o.id == id).map_or(moved, |o| o.transform);
     let same = now.iter().flatten().zip(moved.iter().flatten()).all(|(a, b)| (a - b).abs() <= 1e-6);
     if same {
-        return json!({"occurrence": id, "transform": now, "pending": false});
+        return MoveResult { occurrence: id, transform: now, pending: false, reverted: false, warning: None, param_warnings: Vec::new() };
     }
     let name = s.doc.occurrences.iter().find(|o| o.id == id).map(|o| o.name.clone()).unwrap_or_default();
     // The placement the caller named, else the first one: a part in a component placed more
@@ -781,7 +917,7 @@ fn after_joints(s: &mut Session, p: &Value, id: u64, moved: Mat, cmd: &str) -> V
         "{why}The joints put {name} back where they hold it. To move it, change the joint (joint.edit for its offset or angle, \
          joint.drive for a hinge or slider value), move what it is held to, or use joint.reach"
     );
-    json!({"occurrence": id, "transform": now, "pending": false, "reverted": true, "warning": warning})
+    MoveResult { occurrence: id, transform: now, pending: false, reverted: true, warning: Some(warning), param_warnings: Vec::new() }
 }
 
 fn ground(s: &mut Session, p: &Value) -> Result<Value> {
@@ -794,7 +930,7 @@ fn ground(s: &mut Session, p: &Value) -> Result<Value> {
     let o = s.doc_mut().occurrences.iter_mut().find(|o| o.id == id).ok_or_else(|| bad(cmd, "occurrence"))?;
     o.grounded = want.unwrap_or(!o.grounded);
     let g = o.grounded;
-    Ok(json!({"occurrence": id, "grounded": g}))
+    reply(GroundResult { occurrence: id, grounded: g, param_warnings: Vec::new() })
 }
 
 fn capture(s: &mut Session, _p: &Value) -> Result<Value> {
@@ -808,7 +944,7 @@ fn capture(s: &mut Session, _p: &Value) -> Result<Value> {
         }
     }
     s.revision += 1;
-    Ok(json!({ "captured": n }))
+    reply(CapturePositionResult { captured: n, param_warnings: Vec::new() })
 }
 
 fn revert(s: &mut Session, p: &Value) -> Result<Value> {
@@ -830,7 +966,7 @@ fn revert(s: &mut Session, p: &Value) -> Result<Value> {
     }
     let n = before - s.pending_moves.len();
     s.revision += 1;
-    Ok(json!({ "reverted": n }))
+    reply(RevertPositionResult { reverted: n, param_warnings: Vec::new() })
 }
 
 /// The active component's frame from world coordinates (for new features' geometry).

crates/engine/src/cmd/component_clone.rs

@@ -4,8 +4,9 @@ use solidcraft_geom::prelude::*;
 use std::collections::{BTreeMap, BTreeSet};
 
 use crate::params::bad;
+use crate::schema::component::PasteNewResult;
 use crate::{Result, Sel, Session};
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcraft_doc::{Document, Feature, FeatureKind, Mat, Occurrence};
 
 const CMD: &str = "component.paste_new";
@@ -793,7 +794,16 @@ pub(super) fn build(
         }
     }
     scratch.selection = vec![Sel::Occurrence { path: clone_path }];
-    let out = json!({"component":root,"occurrence":root_occurrence,"features":new_ids,"components":components.len(),"bodies":expected_count,"frozen_bodies":frozen,"notices":notices});
+    let out = super::component::reply(PasteNewResult {
+        component: root,
+        occurrence: root_occurrence,
+        features: new_ids,
+        components: components.len(),
+        bodies: expected_count,
+        frozen_bodies: frozen,
+        notices,
+        param_warnings: Vec::new(),
+    })?;
     Ok((scratch, out))
 }
 

crates/engine/src/cmd/component_drag.rs

@@ -4,11 +4,12 @@
 //! (`joint.reach` moves those as far as their joints allow). A chain of joints joined to nothing
 //! fixed moves as one, so its joints stay as they are.
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcraft_doc::{mat_inverse, mat_mul};
 
 use super::{move_vector, occurrence, occurrence_path, translation, valid_position};
 use crate::params::bad;
+use crate::schema::component::DragResult;
 use crate::{EngineError, Result, Session};
 
 #[cfg(test)]
@@ -158,5 +159,12 @@ pub(super) fn drag(s: &mut Session, p: &Value) -> Result<Value> {
         }
     }
     let continuous = p.get("continuous").and_then(Value::as_bool).unwrap_or(false);
-    Ok(json!({"occurrence": path.last(), "path": path, "moved": moved, "translate": [t.x, t.y, t.z], "continuous": continuous}))
+    super::reply(DragResult {
+        occurrence: path.last().copied().unwrap_or_default(),
+        path,
+        moved,
+        translate: [t.x, t.y, t.z],
+        continuous,
+        param_warnings: Vec::new(),
+    })
 }

crates/engine/src/cmd/component_foreign.rs

@@ -25,9 +25,10 @@ pub(super) fn paste_from_design(s: &mut Session, p: &Value) -> Result<Value> {
     let path = match given {
         Some(path) => path,
         None if to == s.active_component => s.active_occurrence_path.clone().unwrap_or_else(|| s.doc.first_path(to)),
-        None => placing::placement_of(s, &s.placed_document(), to, None, "component_path", cmd)?.0,
+        None => placing::placement_of(s, &s.design_document(), to, None, "component_path", cmd)?.0,
     };
-    let frame = s.placed_document().path_transform(to, &path).ok_or_else(|| bad(cmd, "that path is not a placement of the target"))?;
+    // The target as the design places it, without an exploded view shown.
+    let frame = s.design_document().path_transform(to, &path).ok_or_else(|| bad(cmd, "that path is not a placement of the target"))?;
     let into_target = solidcraft_doc::mat_inverse(&frame).ok_or_else(|| bad(cmd, "the target's frame is not invertible"))?;
     if copy.bodies.is_empty() {
         return paste_components(s, &copy, to, path, into_target, p);

crates/engine/src/cmd/component_properties.rs

@@ -2,13 +2,16 @@
 use solidcraft_geom::prelude::*;
 use std::collections::{BTreeMap, BTreeSet};
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcore_record::Vec3;
 use solidcraft_doc::{Document, Mat};
 use solidcraft_geom::Aabb3;
 use solidcraft_geom::inertia::{self, Tensor3};
 
 use crate::params::bad;
+use crate::schema::component::{
+    BodyProperties, BoundingBox, InertiaAbout, OccurrencePropertiesResult, PhysicalProperties, PropertiesResult, TotalProperties,
+};
 use crate::{Result, Session};
 
 fn descendants(p: &Value, cmd: &str) -> Result<bool> {
@@ -84,10 +87,8 @@ pub(super) fn component(s: &mut Session, p: &Value) -> Result<Value> {
     } else {
         doc.components.iter().find(|c| c.id == id).map(|c| c.name.clone()).ok_or_else(|| bad(cmd, "no active component"))?
     };
-    let mut out = properties(s, &doc, &path, descendants(p, cmd)?, about(p, cmd)?, cmd)?;
-    out["component"] = json!(id);
-    out["name"] = json!(name);
-    Ok(out)
+    let properties = measure(s, &doc, &path, descendants(p, cmd)?, about(p, cmd)?, cmd)?;
+    super::reply(PropertiesResult { component: id, name, properties, param_warnings: Vec::new() })
 }
 
 pub(super) fn occurrence(s: &mut Session, p: &Value) -> Result<Value> {
@@ -105,10 +106,9 @@ pub(super) fn occurrence(s: &mut Session, p: &Value) -> Result<Value> {
             _ => return Err(bad(cmd, "occurrence has multiple placements; supply its `path`")),
         }
     };
-    let mut out = properties(s, &doc, &path, descendants(p, cmd)?, about(p, cmd)?, cmd)?;
-    out["occurrence"] = json!(id);
-    out["name"] = json!(doc.occurrences.iter().find(|o| o.id == id).map(|o| o.name.as_str()));
-    Ok(out)
+    let properties = measure(s, &doc, &path, descendants(p, cmd)?, about(p, cmd)?, cmd)?;
+    let name = doc.occurrences.iter().find(|o| o.id == id).map(|o| o.name.clone());
+    super::reply(OccurrencePropertiesResult { occurrence: id, name, properties, param_warnings: Vec::new() })
 }
 
 /// The linear part of `m` is a rotation (no scale, shear or mirror), to rounding.
@@ -200,7 +200,7 @@ fn measure_placed(body: &solidcraft_doc::ModelBody, transform: Mat) -> Result<Pl
     })
 }
 
-fn properties(s: &Session, doc: &Document, selected: &[u64], descendants: bool, about: Option<Vec3>, cmd: &str) -> Result<Value> {
+fn measure(s: &Session, doc: &Document, selected: &[u64], descendants: bool, about: Option<Vec3>, cmd: &str) -> Result<PhysicalProperties> {
     let state = s.model.state();
     let mut bodies = Vec::new();
     let (mut volume, mut area, mut mass) = (0.0, 0.0, 0.0);
@@ -292,13 +292,20 @@ fn properties(s: &Session, doc: &Document, selected: &[u64], descendants: bool,
             faces += measured.faces;
             edges += measured.edges;
             vertices += measured.vertices;
-            bodies.push(json!({"name": body.name, "component": component, "path": path,
-                "material": doc.body_material(&body.name),
-                "closed": closed, "density_g_cm3": closed.then_some(density),
-                "mass_g": closed.then_some(body_mass), "volume_mm3": closed.then_some(measured.volume),
-                "area_mm2": measured.area, "center_of_mass": closed.then_some(measured.centroid),
-                "inertia_g_mm2": body_inertia,
-                "bbox": {"min": measured.bbox.min, "max": measured.bbox.max}}));
+            bodies.push(BodyProperties {
+                name: body.name.to_string(),
+                component,
+                path: path.clone(),
+                material: doc.body_material(&body.name),
+                closed,
+                density_g_cm3: closed.then_some(density),
+                mass_g: closed.then_some(body_mass),
+                volume_mm3: closed.then_some(measured.volume),
+                area_mm2: measured.area,
+                center_of_mass: closed.then_some(measured.centroid),
+                inertia_g_mm2: body_inertia,
+                bbox: BoundingBox { min: measured.bbox.min, max: measured.bbox.max },
+            });
         }
     }
     if let Some(w) = &watch {
@@ -321,19 +328,36 @@ fn properties(s: &Session, doc: &Document, selected: &[u64], descendants: bool,
     });
     let at_centre = at_centre.filter(|i| i.iter().flatten().all(|x| x.is_finite()));
     let principal = at_centre.and_then(|i| inertia::principal(&i, EQUAL_MOMENTS));
-    let bbox = if bodies.is_empty() { Value::Null } else { json!({"min": bounds.min, "max": bounds.max}) };
-    let mut out = json!({"path": selected, "coordinate_frame": "world", "descendants": descendants,
-        "placement_count": placement_count, "body_count": bodies.len(), "bodies": bodies,
-        "total": {"open_bodies_skipped": skipped, "volume_mm3": volume, "area_mm2": area, "mass_g": mass,
-            "center_of_mass": centroid, "first_moment_g_mm": moment, "inertia_g_mm2": at_centre,
-            "principal_moments_g_mm2": principal.map(|(moments, _)| moments), "principal_axes": principal.map(|(_, axes)| axes),
-            "bbox": bbox, "faces": faces, "edges": edges, "vertices": vertices}});
-    if let Some(point) = about {
+    let bbox = (!bodies.is_empty()).then_some(BoundingBox { min: bounds.min, max: bounds.max });
+    let inertia_about = about.map(|point| {
         let shifted =
             centroid.zip(at_centre).map(|(c, i)| inertia::shifted(&i, mass, point - c)).filter(|i| i.iter().flatten().all(|x| x.is_finite()));
-        out["total"]["inertia_about"] = json!({"point": point, "inertia_g_mm2": shifted});
-    }
-    Ok(out)
+        InertiaAbout { point, inertia_g_mm2: shifted }
+    });
+    Ok(PhysicalProperties {
+        path: selected.to_vec(),
+        coordinate_frame: "world".to_string(),
+        descendants,
+        placement_count,
+        body_count: bodies.len(),
+        bodies,
+        total: TotalProperties {
+            open_bodies_skipped: skipped,
+            volume_mm3: volume,
+            area_mm2: area,
+            mass_g: mass,
+            center_of_mass: centroid,
+            first_moment_g_mm: moment,
+            inertia_g_mm2: at_centre,
+            principal_moments_g_mm2: principal.map(|(moments, _)| moments),
+            principal_axes: principal.map(|(_, axes)| axes),
+            bbox,
+            faces,
+            edges,
+            vertices,
+            inertia_about,
+        },
+    })
 }
 
 /// The tessellating work a properties command did on this thread, for tests: placed copies

crates/engine/src/cmd/component_sketches_to_parts.rs

@@ -36,7 +36,9 @@ pub(super) fn reauthor(s: &mut Session, id: u64, to: u64, cmd: &str) -> Result<(
     if from == to {
         return Ok(());
     }
-    let doc = s.placed_document();
+    // Both placements as the design has them: an exploded view shown would move the sketch by
+    // the difference of its offsets.
+    let doc = s.design_document();
     let path = if to == anchor.component {
         anchor.path.clone()
     } else if to == 0 {

crates/engine/src/cmd/component_transfer.rs

@@ -1,5 +1,6 @@
 //! Atomic timeline ownership changes, preserving the selected world geometry.
 use super::*;
+use crate::schema::component::{BodyComponent, FromBodiesResult, MoveBodiesResult};
 use solidcraft_doc::BodyName;
 use std::collections::{BTreeMap, BTreeSet};
 
@@ -128,10 +129,10 @@ pub(super) fn from_bodies(s: &mut Session, p: &Value) -> Result<Value> {
     for (name, component) in bodies.into_iter().zip(targets) {
         let feature = transfer(&mut scratch, &name, component, &frames, cmd)?;
         features.push(feature);
-        made.push(json!({"component":component,"body":name,"feature":feature}));
+        made.push(BodyComponent { component, body: name, feature });
     }
     finish(s, &mut scratch, &features, cmd)?;
-    Ok(json!({"components":made}))
+    super::reply(FromBodiesResult { components: made, param_warnings: Vec::new() })
 }
 
 /// A placement path parameter (`component_path`: the target's placement to place by,
@@ -187,7 +188,7 @@ fn move_at_boundary(s: &mut Session, p: &Value, allow_boundary: bool) -> Result<
         features.push(transfer(&mut scratch, name, to, &frames, cmd)?);
     }
     finish(s, &mut scratch, &features, cmd)?;
-    Ok(json!({"bodies":bodies,"component":to,"features":features}))
+    super::reply(MoveBodiesResult { bodies, component: to, features, param_warnings: Vec::new() })
 }
 
 #[cfg(test)]

crates/engine/src/cmd/config.rs

@@ -136,10 +136,12 @@ fn column_of(s: &Session, p: &Value, cmd: &str) -> Result<Column> {
     for (key, appearance) in [("material", false), ("appearance", true)] {
         if let Some(body) = str_(p, key) {
             let c = if appearance { Column::Appearance(body.to_string()) } else { Column::Material(body.to_string()) };
-            if !s.doc.configs.columns.contains(&c) && s.model.state().body(body).is_none() {
-                return Err(bad(cmd, format!("no body `{body}`")));
+            if s.doc.configs.columns.contains(&c) {
+                return Ok(c);
             }
-            return Ok(c);
+            // A placed copy's name means the body it shows (#9740); the column is keyed by that body's own name.
+            let body = s.own_body_name(body).ok_or_else(|| bad(cmd, format!("no body `{body}`")))?;
+            return Ok(if appearance { Column::Appearance(body) } else { Column::Material(body) });
         }
     }
     if let Some(n) = str_(p, "param") {
@@ -538,6 +540,20 @@ mod tests {
 
     use crate::Session;
 
+    /// A placed copy's body name (`KB (K:2)`, as inspect.measure lists it) means the body it
+    /// shows: the column is keyed by that body's own name, for every placement.
+    #[test]
+    fn a_column_by_a_placed_copys_name_is_keyed_by_the_body_it_shows() {
+        let mut s = Session::default();
+        run(&mut s, "component.create", json!({"name": "K"}));
+        run(&mut s, "solid.box", json!({"body_name": "KB", "length": 10, "width": 10, "height": 10}));
+        run(&mut s, "occurrence.copy", json!({"component": "K", "translate": [30, 0, 0]}));
+        run(&mut s, "config.column", json!({"material": "KB (K:2)"}));
+        assert!(s.doc.configs.columns.contains(&super::Column::Material("KB".into())), "{:?}", s.doc.configs.columns);
+        let err = s.execute("config.column", &json!({"material": "KB (K:9)"})).unwrap_err().to_string();
+        assert!(err.contains("no body `KB (K:9)`"), "{err}");
+    }
+
     fn run(s: &mut Session, id: &str, p: Value) -> Value {
         match s.execute(id, &p) {
             Ok(v) => v,

crates/engine/src/cmd/delete.rs

@@ -10,11 +10,19 @@ use solidcraft_doc::FeatureKind;
 
 use super::{CommandSpec, sketch_store};
 use crate::params::{bad, bool_};
+use crate::schema::delete::{SelectionDeleteParams, SelectionDeleteResult};
+use crate::schema::{TypedContract, output_schema_for};
 use crate::{EngineError, Result, Sel, Session};
 
-pub static COMMANDS: &[CommandSpec] = &[CommandSpec::new("selection.delete", "Delete", delete).icon("delete").params(
-    "items?: [selection items]; components?, occurrences?, canvases?, point_clouds?, joints?: [ids or names]; dry_run?: bool → deleted, deleted_joints, would_fail, skipped (one undo step)",
-)];
+const DELETE_CONTRACT: TypedContract<SelectionDeleteParams> = TypedContract::new();
+
+pub static COMMANDS: &[CommandSpec] = &[CommandSpec::new("selection.delete", "Delete", crate::checked!("selection.delete", delete))
+    .icon("delete")
+    .contract(&DELETE_CONTRACT)
+    .output(output_schema_for::<SelectionDeleteResult>)
+    .params(
+        "items?: [selection items]; components?, occurrences?, canvases?, point_clouds?, joints?: [ids or names]; dry_run?: bool → deleted, deleted_joints, would_fail, skipped (one undo step)",
+    )];
 
 /// Run another command's body inside this one (so the whole delete is one undo step).
 fn sub(s: &mut Session, id: &str, p: Value) -> Result<Value> {
@@ -227,11 +235,12 @@ fn apply(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad(cmd, skipped.first().cloned().unwrap_or_else(|| "nothing to delete".into())));
     }
     s.refresh();
-    let deleted: Vec<&String> = features_before.iter().filter(|(id, _)| s.doc.feature(*id).is_none()).map(|(_, n)| n).collect();
+    let deleted: Vec<String> = features_before.iter().filter(|(id, _)| s.doc.feature(*id).is_none()).map(|(_, n)| n.clone()).collect();
     // Features after a rolled-back marker count too (#3471).
     let would_fail: Vec<String> =
         super::edit::newly_broken_in_history(&before_doc, &before, &s.doc, &s.model).into_iter().map(|(name, _)| name).collect();
-    Ok(json!({ "deleted": deleted, "deleted_joints": joints, "bodies": bodies, "would_fail": would_fail, "skipped": skipped }))
+    let reply = SelectionDeleteResult { deleted, deleted_joints: joints, bodies, would_fail, skipped, param_warnings: Vec::new() };
+    serde_json::to_value(reply).map_err(|e| bad(cmd, e.to_string()))
 }
 
 #[cfg(test)]

crates/engine/src/cmd/edit.rs

@@ -8,6 +8,17 @@ use solidcraft_doc::{Feature, FeatureKind};
 
 use super::CommandSpec;
 use crate::params::{bad, bool_, name_or_id_values, num, str_};
+use crate::schema::edit::{
+    BrokenFeature, FailingFeature, FeatureInfo, FeatureInput, Inspected, OmittedField, SuppressChanged, TimelineComputeAllParams,
+    TimelineComputeAllResult, TimelineDeleteParams, TimelineDeleteResult, TimelineDependentsParams, TimelineDependentsResult, TimelineEditParams,
+    TimelineEditResult, TimelineGroupMade, TimelineGroupParams, TimelineGroupRenamed, TimelineInspectParams, TimelineInspectResult,
+    TimelineMarkerResult, TimelineMoveManyParams, TimelineMoveToGroupParams, TimelineMoved, TimelineMovedToGroup, TimelineRedefineParams,
+    TimelineRedefined, TimelineRenameGroupParams, TimelineRenameParams, TimelineRenameResult, TimelineReorderManyParams, TimelineReorderParams,
+    TimelineReordered, TimelineReorderedMany, TimelineRollToParams, TimelineRollbackParams, TimelineSuppressParams, TimelineSuppressResult,
+    TimelineUngroupParams, TimelineUngrouped,
+};
+use crate::schema::select::{PartialPick, SelectClearParams, SelectClearResult, SelectItem, SelectSetParams, SelectSetResult, read_item};
+use crate::schema::{TypedContract, output_schema_for};
 use crate::{EngineError, Result, Sel, Session, Snapshot};
 
 pub static COMMANDS: &[CommandSpec] = &[
@@ -53,7 +64,12 @@ pub static COMMANDS: &[CommandSpec] = &[
         .contract(&RESTORE_CHECKPOINT_CONTRACT)
         .output(crate::schema::output_schema_for::<crate::schema::edit::CheckpointResult>)
         .params("checkpoint: id; forget?: bool (true = drop it without going back). Goes back to it, undo history included. Restoring or forgetting uses it and every later checkpoint up: take a new one to go back again"),
-    CommandSpec::new("timeline.compute_all", "Compute All", compute_all).at("SOLID", "MODIFY").icon("compute").noundo(),
+    CommandSpec::new("timeline.compute_all", "Compute All", crate::checked!("timeline.compute_all", compute_all))
+        .at("SOLID", "MODIFY")
+        .icon("compute")
+        .noundo()
+        .contract(&COMPUTE_ALL_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineComputeAllResult>),
     CommandSpec::new("timeline.play", "Play History", crate::checked!("timeline.play", play))
         .at("INSPECT", "HISTORY")
         .icon("timeline_play")
@@ -63,64 +79,145 @@ pub static COMMANDS: &[CommandSpec] = &[
         .contract(&PLAY_CONTRACT)
         .output(crate::schema::output_schema_for::<crate::schema::edit::TimelinePlayResult>)
         .params("action?: toggle|play|stop (default toggle) → action: validated display request; the connected UI plays from the marker to the end with a half-second pause per rebuilt step. Headless callers only validate the request; no dialog, document edit or animation clock is created"),
-    CommandSpec::new("timeline.delete", "Delete", delete)
+    CommandSpec::new("timeline.delete", "Delete", crate::checked!("timeline.delete", delete))
         .at("SOLID", "MODIFY")
         .icon("delete")
         .key("Delete")
+        .contract(&DELETE_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineDeleteResult>)
         .params("feature: id|name | features: [id|name] | groups: [timeline folder ids] (a folder goes with all its features, joints and nested folders; one undo step; a sketch takes its dependent features with it) → deleted: [feature ids]; joints?: [joint ids]; groups?: [folder ids deleted]; failing?: [{feature, error}] (later features that worked and now fail)"),
-    CommandSpec::new("timeline.rename", "Rename", rename).icon("rename").params("feature: id|name, name (references to it follow)"),
-    CommandSpec::new("timeline.group", "New Feature Folder", group)
+    CommandSpec::new("timeline.rename", "Rename", crate::checked!("timeline.rename", rename))
+        .icon("rename")
+        .contract(&RENAME_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineRenameResult>)
+        .params("feature: id|name, name (references to it follow)"),
+    CommandSpec::new("timeline.group", "New Feature Folder", crate::checked!("timeline.group", group))
         .icon("folder")
         .doc_only()
+        .contract(&GROUP_CONTRACT)
+        .output(output_schema_for::<TimelineGroupMade>)
         .params("name?; features?: [id|name]; joints?: [id|name]; groups?: [folder ids]; parent?: folder id (features and joints leave any other timeline folder)"),
-    CommandSpec::new("timeline.ungroup", "Remove Feature Folders", ungroup).icon("folder")
+    CommandSpec::new("timeline.ungroup", "Remove Feature Folders", crate::checked!("timeline.ungroup", ungroup))
+        .icon("folder")
         .doc_only()
+        .contract(&UNGROUP_CONTRACT)
+        .output(output_schema_for::<TimelineUngrouped>)
         .params("group: id | groups: [ids] (features and joints remain in the timeline)"),
-    CommandSpec::new("timeline.rename_group", "Rename Feature Folder", rename_group).icon("rename").doc_only().params("group: id, name (renames the folder holding features and joints)"),
-    CommandSpec::new("timeline.move_to_group", "Move Features to Folder", move_to_group).icon("folder")
+    CommandSpec::new("timeline.rename_group", "Rename Feature Folder", crate::checked!("timeline.rename_group", rename_group))
+        .icon("rename")
         .doc_only()
+        .contract(&RENAME_GROUP_CONTRACT)
+        .output(output_schema_for::<TimelineGroupRenamed>)
+        .params("group: id, name (renames the folder holding features and joints)"),
+    CommandSpec::new("timeline.move_to_group", "Move Features to Folder", crate::checked!("timeline.move_to_group", move_to_group))
+        .icon("folder")
+        .doc_only()
+        .contract(&MOVE_TO_GROUP_CONTRACT)
+        .output(output_schema_for::<TimelineMovedToGroup>)
         .params("features?: [id|name], joints?: [id|name], groups?: [ids], group?: id (omit or null to move to the timeline root)"),
-    CommandSpec::new("timeline.move_many", "Move Timeline Items", move_many).icon("reorder").params(
+    CommandSpec::new("timeline.move_many", "Move Timeline Items", crate::checked!("timeline.move_many", move_many))
+        .icon("reorder")
+        .contract(&MOVE_MANY_CONTRACT)
+        .output(output_schema_for::<TimelineMoved>)
+        .params(
         "features?: [id|name], groups?: [folder ids], group?: folder id, position: insertion slot, active?: bool (true = the moved contents end up before the history marker, false = behind it; other features keep their state); atomically changes folder membership and moves all selected contents as one block",
     ),
-    CommandSpec::new("timeline.rollback", "Move Timeline Marker", rollback).icon("rollback").params("position: number of features to keep active, or \"end\" (omit = end)"),
-    CommandSpec::new("timeline.roll_to", "Roll History Marker", roll_to).icon("rollback")
+    CommandSpec::new("timeline.rollback", "Move Timeline Marker", crate::checked!("timeline.rollback", rollback))
+        .icon("rollback")
+        .contract(&ROLLBACK_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineMarkerResult>)
+        .params("position: number of features to keep active, or \"end\" (omit = end)"),
+    CommandSpec::new("timeline.roll_to", "Roll History Marker", crate::checked!("timeline.roll_to", roll_to))
+        .icon("rollback")
+        .contract(&ROLL_TO_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineMarkerResult>)
         .params("position: number of features to keep active, or \"end\" (omit = end) | feature: id|name (the marker goes right after it)"),
-    CommandSpec::new("timeline.reorder", "Reorder Feature", reorder).icon("reorder")
+    CommandSpec::new("timeline.reorder", "Reorder Feature", crate::checked!("timeline.reorder", reorder))
+        .icon("reorder")
+        .contract(&REORDER_CONTRACT)
+        .output(output_schema_for::<TimelineReordered>)
         .params("feature: id|name, position: its new index, active?: bool (true = it ends up before the history marker, false = behind it; other features keep their state); refused when a feature that worked would fail, unless allow_errors?: bool (default false): then made, and broken: [{feature, error}] lists the features it broke → feature, position: its index now, from: its index before, moved: bool, note?: why nothing moved, or that a position past the end meant the last slot"),
-    CommandSpec::new("timeline.reorder_many", "Reorder Features", reorder_many).icon("reorder").params(
+    CommandSpec::new("timeline.reorder_many", "Reorder Features", crate::checked!("timeline.reorder_many", reorder_many))
+        .icon("reorder")
+        .contract(&REORDER_MANY_CONTRACT)
+        .output(output_schema_for::<TimelineReorderedMany>)
+        .params(
         "features: [id|name], position: insertion slot in the current history; selected features keep their relative order; active?: bool (as timeline.reorder's); refused when a feature that worked would fail, unless allow_errors?: bool (default false): then made, and broken: [{feature, error}] lists the features it broke",
     ),
-    CommandSpec::new("timeline.redefine", "Edit Feature", redefine).icon("edit")
+    CommandSpec::new("timeline.redefine", "Edit Feature", crate::checked!("timeline.redefine", redefine))
+        .icon("edit")
+        .contract(&REDEFINE_CONTRACT)
+        .output(output_schema_for::<TimelineRedefined>)
         .params("feature: id|name, command: the feature's command id, params: its parameters (the feature is rebuilt in place) → feature, recomputed, restored, rolled_back: bool (the feature is after the history marker, so the edit is not built yet; `note` then says so), warning?"),
-    CommandSpec::new("timeline.dependents", "Feature Dependents", dependents).icon("graph")
+    CommandSpec::new("timeline.dependents", "Feature Dependents", crate::checked!("timeline.dependents", dependents))
+        .icon("graph")
         .noundo()
+        .contract(&DEPENDENTS_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineDependentsResult>)
         .params("feature: id|name → features deleted with it, and features that would fail without it"),
-    CommandSpec::new("timeline.suppress", "Suppress Feature", suppress).icon("suppress").params(
+    CommandSpec::new("timeline.suppress", "Suppress Feature", crate::checked!("timeline.suppress", suppress))
+        .icon("suppress")
+        .contract(&SUPPRESS_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineSuppressResult>)
+        .params(
         "feature: id|name | features: [id|name] | groups: [timeline folder ids] (every feature and joint in those folders and their nested \
          folders; one undo step), suppressed?: bool (default toggles: features and joints are all \
          suppressed unless all of them already are, then all are unsuppressed) → feature: id (or features: [ids]; groups: [ids] and joints: [ids] when groups are given), suppressed",
     ),
-    CommandSpec::new("timeline.edit", "Edit Feature", edit_feature).icon("edit").params(
+    CommandSpec::new("timeline.edit", "Edit Feature", crate::checked!("timeline.edit", edit_feature))
+        .icon("edit")
+        .contract(&EDIT_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineEditResult>)
+        .params(
         "feature: id|name, set: {fields to change, merged into the feature's definition as timeline.inspect returns it, \
          e.g. {\"extent\": {\"distance\": \"30\"}} (extrude), {\"angle\": \"90 deg\"} (revolve); \
          a dotted key names a nested field ({\"plane.distance\": \"8 mm\"} = {\"plane\": {\"distance\": \"8 mm\"}}); \
          expressions are text, or a number in mm or degrees} → recomputed: features rebuilt, restored: features whose earlier result for the same inputs was reused",
     ),
-    CommandSpec::new("timeline.inspect", "Inspect Feature", inspect_feature).icon("inspect").noundo().params(
+    CommandSpec::new("timeline.inspect", "Inspect Feature", crate::checked!("timeline.inspect", inspect_feature))
+        .icon("inspect")
+        .noundo()
+        .contract(&INSPECT_CONTRACT)
+        .output(crate::schema::output_schema_for::<TimelineInspectResult>)
+        .params(
         "group: folder id → group, name, parent, features, joints; or feature: id|name → type, definition (the fields timeline.edit's set changes, with their current values), \
          inputs: [{label, param, expression, unit}] (named inputs parameters.change can also set), error, warning",
     ),
-    CommandSpec::new("select.set", "Select", select_set).icon("select")
+    CommandSpec::new("select.set", "Select", crate::checked!("select.set", select_set)).icon("select")
         .noundo()
+        .contract(&SELECT_SET_CONTRACT)
+        .output(output_schema_for::<SelectSetResult>)
         .params("items: [{type: body|edge|face|feature|sketch_curve|sketch_point|profile, …}], add?: bool; face/edge: body plus point [x,y,z] in world mm or index (both also accepted); a point uses Measure's pick tolerance, an index supplies a point on the item; invalid partial picks leave the selection unchanged"),
     CommandSpec::new("select.filter", "Selection filter", select_filter).icon("select").noundo().doc_only()
         .params("mode: body|face|component → validated UI pick granularity; headless echo only, no document edits or undo"),
-    CommandSpec::new("select.clear", "Clear Selection", select_clear).icon("select").noundo(),
+    CommandSpec::new("select.clear", "Clear Selection", crate::checked!("select.clear", select_clear))
+        .icon("select")
+        .noundo()
+        .contract(&SELECT_CLEAR_CONTRACT)
+        .output(output_schema_for::<SelectClearResult>),
     CommandSpec::new("select.same_look", "Select Same Look", select_same_look).icon("select").noundo().doc_only()
         .params("body?: world body name, face?: face index; defaults to the current body/face selection → selects objects using the resolved appearance"),
 ];
 
+const SELECT_SET_CONTRACT: TypedContract<SelectSetParams> = TypedContract::new();
+const SELECT_CLEAR_CONTRACT: TypedContract<SelectClearParams> = TypedContract::new();
+const COMPUTE_ALL_CONTRACT: TypedContract<TimelineComputeAllParams> = TypedContract::new();
+const DELETE_CONTRACT: TypedContract<TimelineDeleteParams> = TypedContract::new();
+const RENAME_CONTRACT: TypedContract<TimelineRenameParams> = TypedContract::new();
+const ROLLBACK_CONTRACT: TypedContract<TimelineRollbackParams> = TypedContract::new();
+const ROLL_TO_CONTRACT: TypedContract<TimelineRollToParams> = TypedContract::new();
+const DEPENDENTS_CONTRACT: TypedContract<TimelineDependentsParams> = TypedContract::new();
+const SUPPRESS_CONTRACT: TypedContract<TimelineSuppressParams> = TypedContract::new();
+const EDIT_CONTRACT: TypedContract<TimelineEditParams> = TypedContract::new();
+const INSPECT_CONTRACT: TypedContract<TimelineInspectParams> = TypedContract::new();
+const GROUP_CONTRACT: TypedContract<TimelineGroupParams> = TypedContract::new();
+const UNGROUP_CONTRACT: TypedContract<TimelineUngroupParams> = TypedContract::new();
+const RENAME_GROUP_CONTRACT: TypedContract<TimelineRenameGroupParams> = TypedContract::new();
+const MOVE_TO_GROUP_CONTRACT: TypedContract<TimelineMoveToGroupParams> = TypedContract::new();
+const MOVE_MANY_CONTRACT: TypedContract<TimelineMoveManyParams> = TypedContract::new();
+const REORDER_CONTRACT: TypedContract<TimelineReorderParams> = TypedContract::new();
+const REORDER_MANY_CONTRACT: TypedContract<TimelineReorderManyParams> = TypedContract::new();
+const REDEFINE_CONTRACT: TypedContract<TimelineRedefineParams> = TypedContract::new();
 const PLAY_CONTRACT: crate::schema::TypedContract<crate::schema::edit::TimelinePlayParams> = crate::schema::TypedContract::new();
 
 fn play(_s: &mut Session, p: &Value) -> Result<Value> {
@@ -222,7 +319,7 @@ fn compute_all(s: &mut Session, _p: &Value) -> Result<Value> {
     s.set_validation(validation);
     s.refresh();
     let errors = s.model.results.iter().filter(|r| r.error.is_some()).count();
-    Ok(json!({"features": s.model.results.len(), "errors": errors}))
+    reply("timeline.compute_all", TimelineComputeAllResult { features: s.model.results.len(), errors, param_warnings: Vec::new() })
 }
 
 pub(super) fn feature_id(s: &Session, v: Option<&Value>, cmd: &str) -> Result<u64> {
@@ -269,24 +366,21 @@ fn delete(s: &mut Session, p: &Value) -> Result<Value> {
     }
     s.selection.clear();
     s.refresh();
-    let failing: Vec<Value> = s
+    let failing: Vec<FailingFeature> = s
         .model
         .results
         .iter()
         .filter(|r| worked.contains(&r.id))
-        .filter_map(|r| r.error.as_ref().map(|e| json!({"feature": r.name, "error": e})))
+        .filter_map(|r| r.error.as_ref().map(|e| FailingFeature { feature: r.name.clone(), error: e.clone() }))
         .collect();
-    let mut out = json!({"deleted": gone});
-    if !joints.is_empty() {
-        out["joints"] = json!(joints);
-    }
-    if !folders.is_empty() {
-        out["groups"] = json!(folders);
-    }
-    if !failing.is_empty() {
-        out["failing"] = json!(failing);
-    }
-    Ok(out)
+    let out = TimelineDeleteResult {
+        deleted: gone,
+        joints: (!joints.is_empty()).then_some(joints),
+        groups: (!folders.is_empty()).then(|| folders.into_iter().collect()),
+        failing: (!failing.is_empty()).then_some(failing),
+        param_warnings: Vec::new(),
+    };
+    reply(cmd, out)
 }
 
 fn rename(s: &mut Session, p: &Value) -> Result<Value> {
@@ -302,7 +396,7 @@ fn rename(s: &mut Session, p: &Value) -> Result<Value> {
         super::features::check_plane_name(name, cmd)?;
     }
     if name == old {
-        return Ok(json!({"feature": id, "name": name}));
+        return reply(cmd, TimelineRenameResult { feature: id, name: name.to_string(), param_warnings: Vec::new() });
     }
     let names = BTreeMap::from([(old.clone(), name.to_string())]);
     let sketches = BTreeMap::new();
@@ -322,7 +416,7 @@ fn rename(s: &mut Session, p: &Value) -> Result<Value> {
             *n = name.to_string();
         }
     }
-    Ok(json!({"feature": id, "name": name}))
+    reply(cmd, TimelineRenameResult { feature: id, name: name.to_string(), param_warnings: Vec::new() })
 }
 
 fn timeline_group_id(s: &Session, p: &Value, cmd: &str) -> Result<u64> {
@@ -561,7 +655,7 @@ fn group(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(not_contiguous(&folders, broken, cmd));
     }
     s.doc_mut().timeline_groups = folders;
-    Ok(json!({"group": id, "name": name, "parent": parent, "groups": groups}))
+    reply(cmd, TimelineGroupMade { group: id, name, parent, groups, param_warnings: Vec::new() })
 }
 
 fn ungroup(s: &mut Session, p: &Value) -> Result<Value> {
@@ -618,7 +712,7 @@ fn ungroup(s: &mut Session, p: &Value) -> Result<Value> {
     sort_group_features(&mut next);
     require_contiguous_groups(&next, cmd)?;
     *s.doc_mut() = next;
-    Ok(json!({"groups": ids}))
+    reply(cmd, TimelineUngrouped { groups: ids, param_warnings: Vec::new() })
 }
 
 fn rename_group(s: &mut Session, p: &Value) -> Result<Value> {
@@ -631,7 +725,7 @@ fn rename_group(s: &mut Session, p: &Value) -> Result<Value> {
     if let Some(group) = s.doc_mut().timeline_groups.iter_mut().find(|group| group.id == id) {
         group.name = name.to_string();
     }
-    Ok(json!({"group": id, "name": name}))
+    reply(cmd, TimelineGroupRenamed { group: id, name: name.to_string(), param_warnings: Vec::new() })
 }
 
 fn move_to_group(s: &mut Session, p: &Value) -> Result<Value> {
@@ -668,7 +762,7 @@ fn move_to_group(s: &mut Session, p: &Value) -> Result<Value> {
     sort_group_features(&mut next);
     require_contiguous_groups(&next, cmd)?;
     *s.doc_mut() = next;
-    Ok(json!({"features": features, "joints": joints, "groups": groups, "group": target}))
+    reply(cmd, TimelineMovedToGroup { features, joints, groups, group: target, param_warnings: Vec::new() })
 }
 
 fn move_many(s: &mut Session, p: &Value) -> Result<Value> {
@@ -714,7 +808,7 @@ fn move_many(s: &mut Session, p: &Value) -> Result<Value> {
         }
         *s.doc_mut() = next;
     }
-    Ok(json!({"features": ordered, "groups": groups, "group": target, "position": slot}))
+    reply(cmd, TimelineMoved { features: ordered, groups, group: target, position: slot, param_warnings: Vec::new() })
 }
 
 fn rollback(s: &mut Session, p: &Value) -> Result<Value> {
@@ -756,7 +850,7 @@ fn move_marker(s: &mut Session, p: &Value, cmd: &str) -> Result<Value> {
         _ => None,
     };
     s.selection.clear();
-    Ok(json!({"marker": s.doc.marker.unwrap_or(n), "features": n}))
+    reply(cmd, TimelineMarkerResult { marker: s.doc.marker.unwrap_or(n), features: n, param_warnings: Vec::new() })
 }
 
 /// The features named by `feature: id|name` and/or `features: [id|name]` (or one id|name), in
@@ -838,11 +932,12 @@ fn suppress(s: &mut Session, p: &Value) -> Result<Value> {
         f.suppressed = want;
     }
     super::joints::suppress_joints(s.doc_mut(), &joints, want);
-    match ids.as_slice() {
-        [id] if groups.is_empty() && p.get("features").is_none_or(Value::is_null) => Ok(json!({"feature": id, "suppressed": want})),
-        _ if groups.is_empty() => Ok(json!({"features": ids, "suppressed": want})),
-        _ => Ok(json!({"features": ids, "joints": joints, "groups": groups, "suppressed": want})),
-    }
+    let changed = match ids.as_slice() {
+        [id] if groups.is_empty() && p.get("features").is_none_or(Value::is_null) => SuppressChanged::One { feature: *id, suppressed: want },
+        _ if groups.is_empty() => SuppressChanged::Features { features: ids, suppressed: want },
+        _ => SuppressChanged::Folders { features: ids, joints, groups, suppressed: want },
+    };
+    reply(cmd, TimelineSuppressResult { changed, param_warnings: Vec::new() })
 }
 
 fn merge(dst: &mut Value, src: &Value, depth: usize) {
@@ -1204,7 +1299,14 @@ fn inspect_feature(s: &mut Session, p: &Value) -> Result<Value> {
     if p.get("group").is_some() {
         let id = timeline_group_id(s, p, cmd)?;
         let group = s.doc.timeline_groups.iter().find(|group| group.id == id).ok_or_else(|| bad(cmd, "folder"))?;
-        return Ok(json!({"group": id, "name": group.name, "parent": group.parent, "features": group.features, "joints": group.joints}));
+        let inspected = Inspected::Group {
+            group: id,
+            name: group.name.clone(),
+            parent: group.parent,
+            features: group.features.clone(),
+            joints: group.joints.clone(),
+        };
+        return reply(cmd, TimelineInspectResult { inspected, param_warnings: Vec::new() });
     }
     let id = feature_id(s, p.get("feature"), cmd)?;
     let f = s.doc.feature(id).ok_or_else(|| bad(cmd, "feature"))?;
@@ -1216,27 +1318,39 @@ fn inspect_feature(s: &mut Session, p: &Value) -> Result<Value> {
         }
         for (k, why) in heavy_fields(&f.kind) {
             if o.remove(*k).is_some() {
-                omitted.push(json!({"field": k, "what": why}));
+                omitted.push(OmittedField { field: k.to_string(), what: why.to_string() });
             }
         }
     }
-    let inputs: Vec<Value> = f
+    let inputs: Vec<FeatureInput> = f
         .kind
         .inputs()
         .into_iter()
         .enumerate()
-        .map(|(i, (label, e, k))| {
-            json!({"label": label, "param": f.param_names.get(i).filter(|n| !n.is_empty()), "expression": e, "unit": k.default_unit()})
+        .map(|(i, (label, e, k))| FeatureInput {
+            label: label.to_string(),
+            param: f.param_names.get(i).filter(|n| !n.is_empty()).cloned(),
+            expression: e,
+            unit: k.default_unit().to_string(),
         })
         .collect();
     let marker = s.doc.marker.unwrap_or(usize::MAX);
     let rolled_back = s.doc.features.iter().position(|x| x.id == id).is_some_and(|i| i >= marker);
     let r = s.model.result(id);
-    Ok(json!({
-        "id": f.id, "name": f.name, "type": f.kind.kind_key(), "type_name": f.kind.type_name(), "suppressed": f.suppressed, "rolled_back": rolled_back,
-        "definition": def, "omitted": omitted, "inputs": inputs,
-        "error": r.and_then(|r| r.error.clone()), "warning": r.and_then(|r| r.warning.clone()),
-    }))
+    let info = FeatureInfo {
+        id: f.id,
+        name: f.name.clone(),
+        kind: f.kind.kind_key().to_string(),
+        type_name: f.kind.type_name().to_string(),
+        suppressed: f.suppressed,
+        rolled_back,
+        definition: def,
+        omitted,
+        inputs,
+        error: r.and_then(|r| r.error.clone()),
+        warning: r.and_then(|r| r.warning.clone()),
+    };
+    reply(cmd, TimelineInspectResult { inspected: Inspected::Feature(Box::new(info)), param_warnings: Vec::new() })
 }
 
 fn edit_feature(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1334,27 +1448,17 @@ fn edit_feature(s: &mut Session, p: &Value) -> Result<Value> {
     if let Some(e) = s.model.result(id).and_then(|r| r.error.clone()) {
         return Err(EngineError::Other(e));
     }
-    Ok(json!({"feature": id, "recomputed": s.model.last_recomputed, "restored": s.model.last_restored}))
+    reply(cmd, TimelineEditResult { feature: id, recomputed: s.model.last_recomputed, restored: s.model.last_restored, param_warnings: Vec::new() })
 }
 
 /// Complete a partial script pick without changing the stored selection type or reinterpreting
 /// an existing index-and-point pair. Unlike Measure, selection keeps the exact face/edge index:
 /// it must not merge a cylinder's patches or a circular rim's arcs into a different item.
 fn selection_item(s: &Session, value: Value) -> Result<Sel> {
-    use solidcore_record::Vec3;
-
-    let kind = value.get("type").and_then(Value::as_str);
-    if !matches!(kind, Some("face" | "edge")) || (value.get("index").is_some() && value.get("point").is_some()) {
-        return serde_json::from_value(value).map_err(|e| bad("select.set", e.to_string()));
-    }
-    let face = kind == Some("face");
-    #[derive(serde::Deserialize)]
-    struct Pick {
-        body: String,
-        index: Option<usize>,
-        point: Option<Vec3>,
-    }
-    let Pick { body, index, point } = serde_json::from_value(value).map_err(|e| bad("select.set", e.to_string()))?;
+    let (face, PartialPick { body, index, point }) = match read_item(value).map_err(|e| bad("select.set", e))? {
+        SelectItem::Exact(sel) => return Ok(sel),
+        SelectItem::Pick { face, pick } => (face, pick),
+    };
     let state = s.world_state()?;
     let b = state.body(&body).ok_or_else(|| bad("select.set", format!("no body `{body}`")))?;
     let missing = || bad("select.set", format!("no {} of `{body}` at the given index or point", if face { "face" } else { "edge" }));
@@ -1429,7 +1533,7 @@ fn select_set(s: &mut Session, p: &Value) -> Result<Value> {
         }
     }
     s.refresh_display();
-    Ok(json!({"selected": s.selection.len()}))
+    reply("select.set", SelectSetResult { selected: s.selection.len(), param_warnings: Vec::new() })
 }
 
 fn select_filter(_s: &mut Session, p: &Value) -> Result<Value> {
@@ -1486,7 +1590,7 @@ fn select_same_look(s: &mut Session, p: &Value) -> Result<Value> {
 fn select_clear(s: &mut Session, _p: &Value) -> Result<Value> {
     s.selection.clear();
     s.refresh_display();
-    Ok(json!({"selected": 0}))
+    reply("select.clear", SelectClearResult { selected: 0, param_warnings: Vec::new() })
 }
 
 /// Features that worked in `before` and fail in `after`: (name, error).
@@ -1593,7 +1697,8 @@ fn reorder(s: &mut Session, p: &Value) -> Result<Value> {
     let active = active_param(p, cmd)?;
     if from == to && active.is_none() {
         let why = capped.map_or_else(|| format!("it is already at position {to}"), |c| format!("{c}, where it already is"));
-        return Ok(json!({"feature": id, "position": to, "from": from, "moved": false, "note": format!("nothing moved: {why}")}));
+        let note = Some(format!("nothing moved: {why}"));
+        return reply(cmd, TimelineReordered { feature: id, position: to, from, moved: false, note, broken: None, param_warnings: Vec::new() });
     }
     let mut next = (*s.doc).clone();
     let f = next.features.remove(from);
@@ -1638,20 +1743,22 @@ fn reorder(s: &mut Session, p: &Value) -> Result<Value> {
         }
         *s.doc_mut() = next;
     }
-    let mut out = json!({"feature": id, "position": now, "from": from, "moved": now != from});
     // With `active`, a feature left in place may still cross the history marker: say which.
     let stayed = (now == from).then(|| {
         let what = if s.doc.marker == marker { "nothing moved" } else { "only the history marker moved" };
         format!("{what}: {name} is already at position {now}")
     });
     let note: Vec<String> = [capped, stayed].into_iter().flatten().collect();
-    if !note.is_empty() {
-        out["note"] = json!(note.join("; "));
-    }
-    if allow {
-        out["broken"] = broken_json(&broken);
-    }
-    Ok(out)
+    let out = TimelineReordered {
+        feature: id,
+        position: now,
+        from,
+        moved: now != from,
+        note: (!note.is_empty()).then(|| note.join("; ")),
+        broken: allow.then(|| broken_features(&broken)),
+        param_warnings: Vec::new(),
+    };
+    reply(cmd, out)
 }
 
 /// The optional `allow_errors` of a move: make it even when it breaks features that worked.
@@ -1664,8 +1771,8 @@ fn allow_errors(p: &Value, cmd: &str) -> Result<bool> {
 }
 
 /// The features a move broke, as `[{feature, error}]`.
-fn broken_json(broken: &[(String, String)]) -> Value {
-    broken.iter().map(|(feature, error)| json!({"feature": feature, "error": error})).collect()
+fn broken_features(broken: &[(String, String)]) -> Vec<BrokenFeature> {
+    broken.iter().map(|(feature, error)| BrokenFeature { feature: feature.clone(), error: error.clone() }).collect()
 }
 
 /// The optional `active` of a move: whether the moved features end up before the history marker.
@@ -1711,11 +1818,8 @@ fn reorder_many(s: &mut Session, p: &Value) -> Result<Value> {
         }
         *s.doc_mut() = next;
     }
-    let mut out = json!({"features": ordered, "position": slot.min(s.doc.features.len())});
-    if allow {
-        out["broken"] = broken_json(&broken);
-    }
-    Ok(out)
+    let position = slot.min(s.doc.features.len());
+    reply(cmd, TimelineReorderedMany { features: ordered, position, broken: allow.then(|| broken_features(&broken)), param_warnings: Vec::new() })
 }
 
 /// The reordered design, the moved features in order, and the model the move was checked on
@@ -2026,15 +2130,20 @@ fn redefine(s: &mut Session, p: &Value) -> Result<Value> {
         if rolled_back { r.get("warning").and_then(Value::as_str).map(str::to_string) } else { s.model.result(id).and_then(|r| r.warning.clone()) };
     // Report the trial's rebuild, plus anything the session still had to compute itself (a kept
     // result its budget dropped); `s.model`'s own counters would only report the reuse (#5694).
-    let mut reply = json!({"feature": id, "recomputed": rebuilt + s.model.last_recomputed, "restored": reused, "rolled_back": rolled_back});
-    if let Some(warning) = warning {
-        reply["warning"] = json!(warning);
-    }
-    if rolled_back {
+    let note = rolled_back.then(|| {
         let name = s.doc.feature(id).map(|f| f.name.clone()).unwrap_or_default();
-        reply["note"] = json!(format!("{name} is after the history marker, so it is not built: move the marker past it to build it"));
-    }
-    Ok(reply)
+        format!("{name} is after the history marker, so it is not built: move the marker past it to build it")
+    });
+    let out = TimelineRedefined {
+        feature: id,
+        recomputed: rebuilt + s.model.last_recomputed,
+        restored: reused,
+        rolled_back,
+        warning,
+        note,
+        param_warnings: Vec::new(),
+    };
+    reply(cmd, out)
 }
 
 fn dependents(s: &mut Session, p: &Value) -> Result<Value> {
@@ -2049,7 +2158,7 @@ fn dependents(s: &mut Session, p: &Value) -> Result<Value> {
     after.evaluate(&next);
     let names = |ids: &[u64]| -> Vec<String> { ids.iter().filter(|x| **x != id).filter_map(|x| s.doc.feature(*x).map(|f| f.name.clone())).collect() };
     let broken: Vec<String> = newly_broken_in_history(&s.doc, &s.model, &next, &after).into_iter().map(|(n, _)| n).collect();
-    Ok(json!({"deleted_with_it": names(&gone), "would_fail": broken}))
+    reply(cmd, TimelineDependentsResult { deleted_with_it: names(&gone), would_fail: broken, param_warnings: Vec::new() })
 }
 
 #[cfg(test)]

crates/engine/src/cmd/extrude_convention_tests.rs

@@ -261,9 +261,9 @@ fn an_older_two_sided_extrude_with_a_negative_distance_keeps_its_sides() {
     let mut base = fixture(json!({"direction":"positive","distance":"10 mm","distance2":"10 mm"}));
     run(&mut base, "parameters.add", json!({"name":"width","expression":"20 mm"}));
     let mut saved: Value = serde_json::from_str(&base.doc.to_json()).unwrap();
-    // As the last release saved it: the format before this build's pending changes.
-    let version: u32 = saved["format"].as_str().unwrap().trim_start_matches("solidcraft/").parse().unwrap();
-    saved["format"] = json!(format!("solidcraft/{}", version - 1));
+    // Format 50 predates the v51 second-side migration. A moving current-1 tag
+    // can already include that migration after unrelated format changes.
+    saved["format"] = json!("solidcraft/50");
     saved.as_object_mut().unwrap().remove("format_pending");
     for (distance, lo, hi) in [("-width", -20.0, 10.0), ("-0 mm", -10.0, 0.0), ("-10 mm", -10.0, 10.0)] {
         let mut file = saved.clone();

crates/engine/src/cmd/features.rs

@@ -13,8 +13,9 @@ use solidcraft_geom::prelude::*;
 use super::{CommandSpec, not_in_sketch};
 use crate::params::{UNKNOWN_COMMAND, bad, bool_, expr, expr_problem, req_expr, str_, string_list, string_list_or_default, vec2, vec3};
 use crate::schema::features::{
-    AppliedRadius, BoundingSolidParams, BoxParams, ConeParams, CylinderParams, ExtrudeParams, FeatureNotice, FeatureResult, FilletParams,
-    FilletResult, NoticeAction, OffsetPlaneParams, PipeParams, PlaneAtAngleParams, ScaleParams, SphereParams, TorusParams,
+    AppliedRadius, BoundingSolidParams, BoxParams, CombineParams, CombineResult, ConeParams, CylinderParams, ExtrudeParams, FeatureNotice,
+    FeatureResult, FilletParams, FilletResult, NoticeAction, OffsetPlaneParams, PipeParams, PlaneAtAngleParams, ScaleParams, SphereParams,
+    TorusParams,
 };
 use crate::schema::{TypedContract, output_schema_for};
 use crate::{EngineError, Result, Session};
@@ -28,6 +29,7 @@ const CONE_CONTRACT: TypedContract<ConeParams> = TypedContract::new();
 const PIPE_CONTRACT: TypedContract<PipeParams> = TypedContract::new();
 const BOUNDING_SOLID_CONTRACT: TypedContract<BoundingSolidParams> = TypedContract::new();
 const SCALE_CONTRACT: TypedContract<ScaleParams> = TypedContract::new();
+const COMBINE_CONTRACT: TypedContract<CombineParams> = TypedContract::new();
 const OFFSET_PLANE_CONTRACT: TypedContract<OffsetPlaneParams> = TypedContract::new();
 const PLANE_AT_ANGLE_CONTRACT: TypedContract<PlaneAtAngleParams> = TypedContract::new();
 const FILLET_CONTRACT: TypedContract<FilletParams> = TypedContract::new();
@@ -85,9 +87,14 @@ pub static COMMANDS: &[CommandSpec] = &[
         .key("F")
         .contract(&FILLET_CONTRACT)
         .output(output_schema_for::<FilletResult>)
-        .params("edges: [[x,y,z] point on edge | {body, index}] ; radius: expr; tangent_chain?: bool (default true: each picked edge's tangent chain is rounded with it; false: exactly the picked edges); body?; type?: constant|curvature (alias g2: curvature-continuous quintic between planar faces along straight edges, one planar end face at each end (including sloped ends); radius sets the equivalent circular setback, not constant curvature; exact fit only)|chord (radius is the width across)|variable (radius at the end nearest start, radius2 at the other; one end may be 0, where the round closes to the corner)|spline (the radius along the edge is a clamped B-spline from the end nearest start: radius is its first control radius, radii the rest, knots its knot vector from 0 to 1; one end may be 0); radius2?; start?: [x,y,z]; radii?: [expr, …]; knots?: [number, …]; mid?: [[position 0…1 from start, radius expr], …] (variable radii between the ends); smooth?: bool (smooth instead of straight between the radii); corner?: rolling|g2 (rolling, the default: the corners where three blended edges meet are pieces of the rolling ball's sphere, tangent to each blend; a curvature round's corners are always g2 patches, between its own sections; g2: each corner where three or more rounded edges meet, and every edge there is rounded, is set back (1.5 × the radius along each edge unless `setbacks` names it) and filled with a patch meeting the rounds and the faces round it to the second order (curvature-continuous seams, clear of the points where a round's section ends on a face), constant-radius exact fillets only, refused where it cannot be built); setbacks?: [{vertex: [x,y,z], distance: expr}, …] (corner setbacks: the corner at the vertex nearest `vertex`, where every edge meeting it is rounded, starts its patch `distance` along each of those edges from the vertex, past where the rounds would meet (past the radius at a square corner), so the rounds blend through a larger patch; one distance for all of a corner's edges; constant-radius exact fillets only; with `corner: g2`, the G2 patch's corners); turn?: mitre|swept (where two rounds turn round a sharp, straight, convex side edge square to both on a plane, such as the rounds along a boss's base at its upright edges: mitre, the default, runs them on to meet in a mitre; swept ends them at the side edge and fills the corner with their section revolved about it, a torus; swept takes type: constant, corner: rolling, no setbacks and fit: exact or reduce, and is refused with the reason where the rounds are unequal or the side edge is concave, curved or tangent); fit?: exact|reduce|taper (exact, the default: a radius too large for the geometry around the edges is refused, naming the largest that fits; reduce: where it doesn't fit it is reduced to the largest that does, one radius for edges sharing a face; the smallest used is returned as `radius_applied`, each edge's as `radii_applied: [{edge: [x,y,z], radius}]`, and noted in the feature's warning; taper: along each straight edge between planar faces where it doesn't fit, the radius follows the room there as a smooth spline, down to 0 where a face closes to a point, noted in the feature's warning)"),
-    CommandSpec::new("solid.chamfer", "Chamfer", chamfer).at("SOLID", "MODIFY").icon("chamfer").params("edges: [[x,y,z] | {body, index}] ; distance: expr; tangent_chain?: bool (default true: each picked edge's tangent chain is cut with it; false: exactly the picked edges); distance2?: expr (along the second face) | angle?: expr (from the first face); flip?: bool (which face is first: by default the one facing up most); body?"),
-    CommandSpec::new("solid.combine", "Combine", combine).at("SOLID", "MODIFY").icon("combine").params("target: body; tools: [body]; operation?: join|cut|intersect; touching?: separate|one_body (what a join makes of pieces that share no face: separate, the default, makes each piece that touches another only along an edge or at a point a body of its own and keeps pieces that touch nothing in one body; one_body keeps every piece in one body); keep_tools?: bool; new_component?: bool (the result goes into a new component; component_name?)"),
+        .params("edges: [[x,y,z] point on edge | {body, index}] ; radius: expr; tangent_chain?: bool (default true: each picked edge's tangent chain is rounded with it; false: exactly the picked edges); body?: the body the edges are on (without it, each point is looked up on every placed body, shown or hidden, and a point on edges of 2 bodies is refused, naming them); type?: constant|curvature (alias g2: curvature-continuous quintic between planar faces along straight edges, one planar end face at each end (including sloped ends); radius sets the equivalent circular setback, not constant curvature; exact fit only)|chord (radius is the width across)|variable (radius at the end nearest start, radius2 at the other; one end may be 0, where the round closes to the corner)|spline (the radius along the edge is a clamped B-spline from the end nearest start: radius is its first control radius, radii the rest, knots its knot vector from 0 to 1; one end may be 0); radius2?; start?: [x,y,z]; radii?: [expr, …]; knots?: [number, …]; mid?: [[position 0…1 from start, radius expr], …] (variable radii between the ends); smooth?: bool (smooth instead of straight between the radii); corner?: rolling|g2 (rolling, the default: the corners where three blended edges meet are pieces of the rolling ball's sphere, tangent to each blend; a curvature round's corners are always g2 patches, between its own sections; g2: each corner where three or more rounded edges meet, and every edge there is rounded, is set back (1.5 × the radius along each edge unless `setbacks` names it) and filled with a patch meeting the rounds and the faces round it to the second order (curvature-continuous seams, clear of the points where a round's section ends on a face), constant-radius exact fillets only, refused where it cannot be built); setbacks?: [{vertex: [x,y,z], distance: expr}, …] (corner setbacks: the corner at the vertex nearest `vertex`, where every edge meeting it is rounded, starts its patch `distance` along each of those edges from the vertex, past where the rounds would meet (past the radius at a square corner), so the rounds blend through a larger patch; one distance for all of a corner's edges; constant-radius exact fillets only; with `corner: g2`, the G2 patch's corners); turn?: mitre|swept (where two rounds turn round a sharp, straight, convex side edge square to both on a plane, such as the rounds along a boss's base at its upright edges: mitre, the default, runs them on to meet in a mitre; swept ends them at the side edge and fills the corner with their section revolved about it, a torus; swept takes type: constant, corner: rolling, no setbacks and fit: exact or reduce, and is refused with the reason where the rounds are unequal or the side edge is concave, curved or tangent); fit?: exact|reduce|taper (exact, the default: a radius too large for the geometry around the edges is refused, naming the largest that fits; reduce: where it doesn't fit it is reduced to the largest that does, one radius for edges sharing a face; the smallest used is returned as `radius_applied`, each edge's as `radii_applied: [{edge: [x,y,z], radius}]`, and noted in the feature's warning; taper: along each straight edge between planar faces where it doesn't fit, the radius follows the room there as a smooth spline, down to 0 where a face closes to a point, noted in the feature's warning)"),
+    CommandSpec::new("solid.chamfer", "Chamfer", chamfer).at("SOLID", "MODIFY").icon("chamfer").params("edges: [[x,y,z] | {body, index}] ; distance: expr; tangent_chain?: bool (default true: each picked edge's tangent chain is cut with it; false: exactly the picked edges); distance2?: expr (along the second face) | angle?: expr (from the first face); flip?: bool (which face is first: by default the one facing up most); body?: the body the edges are on (without it, each point is looked up on every placed body, shown or hidden, and a point on edges of 2 bodies is refused, naming them)"),
+    CommandSpec::new("solid.combine", "Combine", crate::checked!("solid.combine", combine))
+        .at("SOLID", "MODIFY")
+        .icon("combine")
+        .contract(&COMBINE_CONTRACT)
+        .output(output_schema_for::<CombineResult>)
+        .params("target: body; tools: [body]; operation?: join|cut|intersect; touching?: separate|one_body (what a join makes of pieces that share no face: separate, the default, makes each piece that touches another only along an edge or at a point a body of its own and keeps pieces that touch nothing in one body; one_body keeps every piece in one body); keep_tools?: bool; new_component?: bool (the result goes into a new component; component_name?)"),
     CommandSpec::new("solid.pattern.rectangular", "Rectangular Pattern", pattern_rect)
         .at("SOLID", "CREATE")
         .icon("pattern_rect")
@@ -170,7 +177,7 @@ pub static COMMANDS: &[CommandSpec] = &[
         .at("SOLID", "MODIFY")
         .icon("presspull")
         .key("Q")
-        .params("face: [x,y,z] and distance: expr (positive adds material, negative cuts), or edges: [[x,y,z]…] and distance (a fillet)"),
+        .params("face: [x,y,z] and distance: expr (positive adds material, negative cuts), or edges: [[x,y,z]…] and distance (a fillet); body?: the body the face or edges are on (for edges, as for solid.fillet)"),
     CommandSpec::new("solid.move", "Move/Copy", move_bodies).at("SOLID", "MODIFY").icon("move").key("M").enabled(not_in_sketch).params("bodies: [names]; translate?: [x,y,z] (exprs or numbers); axis?: [x,y,z]; angle?: expr; copy?: bool (default false: keeps the original bodies and transforms a new copy instead of moving them in place); occurrences?: [occurrence paths, root first] (only with copy: each component is copied as an independent component, as Paste New copies it, and the copy moves by the same translate, axis and angle in the world; the reply lists the copies in occurrences)"),
 ];
 
@@ -1547,20 +1554,131 @@ fn prim_cone(s: &mut Session, p: &Value) -> Result<Value> {
     add_feature(s, p, FeatureKind::Cone { base, axis: Dir(axis), radius, top_radius, height, operation: operation(p, cmd)? })
 }
 
-/// Edge references → points on the edges.
-fn edge_points(s: &Session, p: &Value, cmd: &str) -> Result<Vec<Vec3>> {
+/// What [`edge_points`] found: a point on each edge, in its body's frame, and the body the
+/// feature keeps (`None`: each edge is looked up on its own).
+struct EdgePicks {
+    points: Vec<Vec3>,
+    body: Option<String>,
+}
+
+/// A body as a pick is looked up on: the model body, the name it is shown by, and the frame it
+/// is placed by and its inverse.
+struct PickRow {
+    body: usize,
+    name: String,
+    frame: solidcraft_doc::Mat,
+    inverse: solidcraft_doc::Mat,
+}
+
+/// What one body's edges near a pick are: the point in its frame, its distance from the pick on
+/// the exact curves and the edge there, whether any edge within reach is not a seam, and the
+/// edges within reach (polyline distance, seam, the direction leaving).
+struct RowHit {
+    row: usize,
+    q: Vec3,
+    d: f64,
+    edge: Option<usize>,
+    edge_like: bool,
+    near: Vec<(f64, bool, Option<Vec3>)>,
+}
+
+/// How many bodies a refusal names before "and N more".
+const NAMED_BODIES: usize = 8;
+
+/// A body's size, its edges' polylines and which of them are seams.
+type EdgeShape = (f64, Vec<Vec<Vec3>>, Vec<bool>);
+
+/// How far a polyline is from `q`.
+fn polyline_dist(points: &[Vec3], q: Vec3) -> f64 {
+    points.windows(2).filter_map(|w| Some(q.dist_to_segment(*w.first()?, *w.get(1)?))).fold(f64::INFINITY, f64::min)
+}
+
+/// How far from an edge of a body this big a pick still means it.
+fn edge_reach(size: f64) -> f64 {
+    size * 0.05 + 1e-3
+}
+
+/// Edge references → points on the edges, each in the frame of the body it lies on.
+///
+/// A point is looked up where it was picked, on every placed body, shown or hidden: a part
+/// whose edge is in the same place only in its own frame is not in the way, and two bodies
+/// with an edge there make it ambiguous. The polylines short-list the edges; which body a pick
+/// means is decided on the exact curves.
+fn edge_points(s: &Session, p: &Value, cmd: &str) -> Result<EdgePicks> {
     let a = p.get("edges").and_then(Value::as_array).ok_or_else(|| bad(cmd, "`edges` must be a list"))?;
     if a.is_empty() || a.len() > 1000 {
         return Err(bad(cmd, "select 1…1000 edges"));
     }
+    let verb = if cmd == "solid.chamfer" { "chamfer" } else { "round" };
     let st = s.model.state();
     // A picked point must lie on an edge (within the distance the kernel re-finds an edge from)
     // of the body the feature names, or of any body: a pick far from every edge would round
-    // whichever edge is nearest (#783). Each body's edges are worked out once.
-    let named = str_(p, "body").filter(|n| st.body(n).is_some());
-    // Per body: its size, its edges' polylines and which of them are seams.
-    let mut candidates: Option<Vec<(f64, Vec<Vec<Vec3>>, Vec<bool>)>> = None;
+    // whichever edge is nearest (#783).
+    let given = str_(p, "body");
+    let named = given.and_then(|n| st.bodies.iter().position(|b| b.name == n));
+    // A pick's own body is the feature's, which keeps one.
+    let agrees = |i: usize| -> Result<usize> {
+        match given {
+            Some(g) if named != Some(i) => {
+                let n = st.bodies.get(i).map_or("", |b| b.name.as_str());
+                Err(bad(cmd, format!("an edge names `{n}`, but `body` is `{g}`: give one")))
+            }
+            _ => Ok(i),
+        }
+    };
+    let identity = |i: usize, b: &solidcraft_doc::ModelBody| PickRow {
+        body: i,
+        name: b.name.clone(),
+        frame: solidcraft_doc::IDENTITY,
+        inverse: solidcraft_doc::IDENTITY,
+    };
+    // Mesh bodies have no edges to pick: rounding one is refused later, saying why.
+    let local: Vec<PickRow> = st.bodies.iter().enumerate().filter(|(_, b)| !b.body.is_mesh()).map(|(i, b)| identity(i, b)).collect();
+    let placed = crate::frames::placed(s);
+    // Worked out for the first pick looked up where it was picked.
+    let world: std::cell::OnceCell<Vec<PickRow>> = std::cell::OnceCell::new();
+    let world_rows = || {
+        world.get_or_init(|| {
+            let index: std::collections::BTreeMap<&str, usize> = st.bodies.iter().enumerate().map(|(i, b)| (b.definition_name(), i)).collect();
+            s.body_frames()
+                .iter()
+                .filter_map(|(name, own, frame)| {
+                    let body = *index.get(own.as_str())?;
+                    let inverse = solidcraft_doc::mat_inverse(frame)?;
+                    (!st.bodies.get(body)?.body.is_mesh()).then(|| PickRow { body, name: name.clone(), frame: *frame, inverse })
+                })
+                .collect()
+        })
+    };
+    // Per body, worked out once.
+    let mut shapes: std::collections::BTreeMap<usize, EdgeShape> = std::collections::BTreeMap::new();
+    let shape_of = |i: usize, shapes: &mut std::collections::BTreeMap<usize, EdgeShape>| {
+        if shapes.contains_key(&i) {
+            return;
+        }
+        let Some(b) = st.bodies.get(i) else { return };
+        let size = b.body.size();
+        let tol = (size * 2e-3).max(1e-3);
+        // The display mesh flags seams (a smooth surface meeting itself, as down the side
+        // of a cylinder), which nobody means by a pick where they end.
+        let shape = match b.body.mesh(&solidcraft_kernel::MeshTolerance::chord(tol)) {
+            // An edge where the faces meet tangentially (the spans of a spline wall
+            // meeting) can't be blended either: nobody means it by a pick.
+            Ok(m) => Some((
+                size,
+                m.edges,
+                m.seams.iter().zip(&m.smooth_edges).map(|(s, t)| *s || *t).chain(m.seams.iter().skip(m.smooth_edges.len()).copied()).collect(),
+            )),
+            Err(_) => b.body.edges(tol).ok().map(|edges| (size, edges.into_iter().map(|e| e.points).collect(), Vec::new())),
+        };
+        if let Some(shape) = shape {
+            shapes.insert(i, shape);
+        }
+    };
     let mut out = Vec::new();
+    // Per pick: the body it was found on, where it was picked, and how far from that body's edge.
+    let mut found: Vec<(usize, String, Vec3, Vec3, f64)> = Vec::new();
+    let mut seen: Vec<Vec3> = Vec::new();
     for e in a {
         let pt = match edge_ref_form(e).map_err(|why| bad(cmd, why))? {
             EdgeRefForm::Point(pt) => pt,
@@ -1569,57 +1687,139 @@ fn edge_points(s: &Session, p: &Value, cmd: &str) -> Result<Vec<Vec3>> {
                 let b = st.body(body).ok_or_else(|| bad(cmd, format!("no body `{body}`")))?;
                 let tol = (b.body.size() * 2e-3).max(1e-3);
                 let edges = b.body.edges(tol)?;
-                out.push(edges.get(idx).ok_or_else(|| bad(cmd, format!("{body} has no edge {idx}")))?.mid);
+                let mid = edges.get(idx).ok_or_else(|| bad(cmd, format!("{body} has no edge {idx}")))?.mid;
+                if let Some(i) = st.bodies.iter().position(|m| m.name == b.name) {
+                    found.push((agrees(i)?, b.name.clone(), mid, mid, 0.0));
+                }
+                out.push(mid);
                 continue;
             }
         };
-        let bodies = candidates.get_or_insert_with(|| {
-            // Mesh bodies have no edges to pick: rounding one is refused later, saying why.
-            st.bodies
+        // The nth pick seen at this point is the nth remembered there.
+        let nth = seen.iter().filter(|q| **q == pt).count();
+        seen.push(pt);
+        let picked = crate::frames::picked_world(pt, nth).filter(|_| placed);
+        let shown = picked.unwrap_or(pt);
+        let own = match e.get("body").and_then(Value::as_str) {
+            Some(n) => Some(agrees(st.bodies.iter().position(|b| b.name == n).ok_or_else(|| bad(cmd, format!("no body `{n}`")))?)?),
+            None => named,
+        };
+        // Named: on that body only, in its frame. Else where it was picked, on every placed body;
+        // a command run by another without the world point, or a design with no placement to look
+        // through, sees the bodies in their own frames.
+        let (w, rows): (Vec3, Vec<&PickRow>) = match (own, picked) {
+            (Some(i), _) => (pt, local.iter().filter(|r| r.body == i).collect()),
+            (None, Some(w)) if !world_rows().is_empty() => (w, world_rows().iter().collect()),
+            _ => (pt, local.iter().collect()),
+        };
+        let q_of = |r: &PickRow| {
+            let q = solidcraft_doc::apply_point(&r.inverse, w);
+            (q.x.is_finite() && q.y.is_finite() && q.z.is_finite()).then_some(q)
+        };
+        // Only bodies whose box (grown by the reach) holds the pick: an edge lies in its body's box.
+        let culled: Vec<(usize, Vec3)> = rows
+            .iter()
+            .enumerate()
+            .filter_map(|(k, r)| {
+                let b = st.bodies.get(r.body)?;
+                let q = q_of(r)?;
+                b.outline_bounds().inflated(edge_reach(b.body.size())).contains(q).then_some((k, q))
+            })
+            .collect();
+        for (k, _) in &culled {
+            if let Some(r) = rows.get(*k) {
+                shape_of(r.body, &mut shapes);
+            }
+        }
+        let mut hits: Vec<RowHit> = Vec::new();
+        for (k, q) in culled {
+            let Some(r) = rows.get(k) else { continue };
+            let (Some((size, edges, seams)), Some(b)) = (shapes.get(&r.body), st.bodies.get(r.body)) else { continue };
+            let chord = (size * 2e-3).max(1e-3);
+            let mut near = Vec::new();
+            let mut candidates = Vec::new();
+            for (i, points) in edges.iter().enumerate() {
+                let d = polyline_dist(points, q);
+                if d <= edge_reach(*size) {
+                    let seam = seams.get(i).copied().unwrap_or(false);
+                    near.push((d, seam, leaving(points, q)));
+                    candidates.push((i, d, seam));
+                }
+            }
+            if near.is_empty() {
+                continue;
+            }
+            // Seams count only where nothing else is near.
+            let edge_like = candidates.iter().any(|(_, _, seam)| !seam);
+            let candidates: Vec<(usize, f64)> = candidates.into_iter().filter(|(_, _, seam)| !edge_like || !seam).map(|(i, d, _)| (i, d)).collect();
+            let polyline = candidates.iter().map(|(_, d)| *d).fold(f64::INFINITY, f64::min);
+            let (d, edge) = candidates
                 .iter()
-                .filter(|b| named.is_none_or(|n| b.name == n) && !b.body.is_mesh())
-                .filter_map(|b| {
-                    let size = b.body.size();
-                    let tol = (size * 2e-3).max(1e-3);
-                    // The display mesh flags seams (a smooth surface meeting itself, as down the side
-                    // of a cylinder), which nobody means by a pick where they end.
-                    match b.body.mesh(&solidcraft_kernel::MeshTolerance::chord(tol)) {
-                        // An edge where the faces meet tangentially (the spans of a spline wall
-                        // meeting) can't be blended either: nobody means it by a pick.
-                        Ok(m) => Some((
-                            size,
-                            m.edges,
-                            m.seams
-                                .iter()
-                                .zip(&m.smooth_edges)
-                                .map(|(s, t)| *s || *t)
-                                .chain(m.seams.iter().skip(m.smooth_edges.len()).copied())
-                                .collect(),
-                        )),
-                        Err(_) => b.body.edges(tol).ok().map(|edges| (size, edges.into_iter().map(|e| e.points).collect(), Vec::new())),
-                    }
-                })
-                .collect()
-        });
+                .filter(|(_, d)| *d <= polyline + 2.0 * chord)
+                .map(|(i, d)| (edge_foot(&b.body, *i, q).map_or(*d, |(_, foot)| solidcraft_doc::apply_point(&r.frame, foot).dist(w)), *i))
+                .fold((f64::INFINITY, None), |best, (d, i)| if d < best.0 { (d, Some(i)) } else { best });
+            hits.push(RowHit { row: k, q, d, edge, edge_like, near });
+        }
+        if hits.is_empty() {
+            if rows.is_empty() {
+                out.push(pt);
+                continue;
+            }
+            // How far the nearest edge is, on every body the pick was looked up on.
+            let mut nearest = f64::INFINITY;
+            for r in &rows {
+                let Some(q) = q_of(r) else { continue };
+                shape_of(r.body, &mut shapes);
+                let Some((_, edges, _)) = shapes.get(&r.body) else { continue };
+                nearest = edges.iter().map(|points| polyline_dist(points, q)).fold(nearest, f64::min);
+            }
+            let far = if nearest.is_finite() { format!("the nearest edge is {nearest:.3} mm away") } else { "there is no edge".to_string() };
+            return Err(bad(cmd, format!("no edge at [{}, {}, {}]: {far}", shown.x, shown.y, shown.z)));
+        }
+        // A body with only a seam there has no edge to blend, where another body has one.
+        if hits.iter().any(|h| h.edge_like) {
+            hits.retain(|h| h.edge_like);
+        }
+        // Bodies with an edge as near as the nearest one's: the pick is on both. A pick off its
+        // curve by e widens the window to about 2e. The same body placed twice, at the same
+        // edge or point of its frame, is one edge.
+        let d_min = hits.iter().map(|h| h.d).fold(f64::INFINITY, f64::min);
+        let mut groups: Vec<&RowHit> = Vec::new();
+        for h in hits.iter().filter(|h| h.d <= 2.0 * d_min + 1e-3) {
+            let Some(r) = rows.get(h.row) else { continue };
+            let size = shapes.get(&r.body).map_or(1.0, |(size, _, _)| *size);
+            let same = |g: &&RowHit| {
+                rows.get(g.row).is_some_and(|o| o.body == r.body) && ((g.edge.is_some() && g.edge == h.edge) || g.q.dist(h.q) <= 1e-6 * size.max(1.0))
+            };
+            if !groups.iter().any(same) {
+                groups.push(h);
+            }
+        }
+        if groups.len() > 1 {
+            let names: Vec<String> = groups.iter().filter_map(|g| rows.get(g.row).map(|r| r.name.clone())).collect();
+            let hidden: String = names.iter().filter(|n| !s.body_visible(n)).map(|n| format!(" ({n} is hidden)")).collect();
+            return Err(bad(
+                cmd,
+                format!(
+                    "[{}, {}, {}] lies on edges of {} bodies, {}: name the one to {verb} with `body`{hidden}",
+                    shown.x,
+                    shown.y,
+                    shown.z,
+                    names.len(),
+                    and_list(&names, NAMED_BODIES)
+                ),
+            ));
+        }
+        let Some(hit) = hits.iter().filter(|h| h.d <= d_min).chain(hits.iter()).next() else { continue };
+        let Some(row) = rows.get(hit.row) else { continue };
         // A point where several edges meet (a corner) is ambiguous: the kernel would round one of
         // them, picked silently (#5173). Edges that carry straight on through the point (the two
         // halves of a circle) are one edge to whoever picked it, and seams and tangent joins don't
-        // count. Directions
-        // come from the polylines' end chords, which lean off a curve's tangent: within about 45°
-        // of opposite counts as carrying on (edges at a real corner are far from opposite).
-        let mut nearest = f64::INFINITY;
-        let mut near = Vec::new();
-        for (size, edges, seams) in bodies.iter() {
-            for (i, points) in edges.iter().enumerate() {
-                let d = points.windows(2).filter_map(|w| Some(pt.dist_to_segment(*w.first()?, *w.get(1)?))).fold(f64::INFINITY, f64::min);
-                nearest = nearest.min(d);
-                if d <= size * 0.05 + 1e-3 {
-                    near.push((d, seams.get(i).copied().unwrap_or(false), leaving(points, pt)));
-                }
-            }
-        }
-        let matches = near.len();
-        let mut meeting: Vec<Option<Vec3>> = near.iter().filter(|(d, seam, _)| !seam && *d <= nearest + 1e-3).map(|(_, _, dir)| *dir).collect();
+        // count. Directions come from the polylines' end chords, which lean off a curve's
+        // tangent: within about 45° of opposite counts as carrying on (edges at a real corner are
+        // far from opposite).
+        let nearest = hit.near.iter().map(|(d, _, _)| *d).fold(f64::INFINITY, f64::min);
+        let mut meeting: Vec<Option<Vec3>> = hit.near.iter().filter(|(d, seam, _)| !seam && *d <= nearest + 1e-3).map(|(_, _, dir)| *dir).collect();
         let mut chains = 0usize;
         while let Some(dir) = meeting.pop() {
             chains += 1;
@@ -1632,16 +1832,107 @@ fn edge_points(s: &Session, p: &Value, cmd: &str) -> Result<Vec<Vec3>> {
         if chains > 1 {
             return Err(bad(
                 cmd,
-                format!("[{}, {}, {}] is where {chains} edges meet: give a point along one edge, such as its midpoint", pt.x, pt.y, pt.z),
+                format!("[{}, {}, {}] is where {chains} edges meet: give a point along one edge, such as its midpoint", shown.x, shown.y, shown.z),
             ));
         }
-        if matches == 0 && !bodies.is_empty() {
-            let far = if nearest.is_finite() { format!("the nearest edge is {nearest:.3} mm away") } else { "there is no edge".to_string() };
-            return Err(bad(cmd, format!("no edge at [{}, {}, {}]: {far}", pt.x, pt.y, pt.z)));
-        }
-        out.push(pt);
+        found.push((row.body, row.name.clone(), hit.q, shown, hit.d));
+        out.push(hit.q);
     }
-    Ok(out)
+    if given.is_some() {
+        return Ok(EdgePicks { points: out, body: given.map(str::to_string) });
+    }
+    let mut bodies: Vec<(usize, String)> = Vec::new();
+    for (i, name, ..) in &found {
+        if !bodies.iter().any(|(b, _)| b == i) {
+            bodies.push((*i, name.clone()));
+        }
+    }
+    let body = match bodies.as_slice() {
+        // One body of several: the feature keeps it, so the model never looks the edges up on
+        // another body that has one in the same place in its own frame.
+        [(i, _)] => st.bodies.get(*i).filter(|_| local.len() > 1).map(|b| b.name.clone()),
+        [] => None,
+        _ => {
+            // Several: each edge is looked up on its own when the model is built, on whichever
+            // body has an edge there in its own frame, so another body's edge there is refused.
+            for (i, _, q, shown, d) in &found {
+                for other in local.iter().filter(|r| r.body != *i) {
+                    let Some(b) = st.bodies.get(other.body) else { continue };
+                    let reach = edge_reach(b.body.size());
+                    if !b.outline_bounds().inflated(reach).contains(*q) {
+                        continue;
+                    }
+                    shape_of(other.body, &mut shapes);
+                    let Some((size, edges, seams)) = shapes.get(&other.body) else { continue };
+                    // The exact curve is no nearer than the polyline less its chord tolerance.
+                    let chord = (size * 2e-3).max(1e-3);
+                    let ghost = edges.iter().enumerate().filter(|(k, _)| !seams.get(*k).copied().unwrap_or(false)).any(|(k, points)| {
+                        let poly = polyline_dist(points, *q);
+                        poly <= reach && poly - chord <= 2.0 * d + 1e-3 && edge_foot(&b.body, k, *q).map_or(poly, |(d, _)| d) <= 2.0 * d + 1e-3
+                    });
+                    if ghost {
+                        let names: Vec<String> = bodies.iter().map(|(_, n)| n.clone()).collect();
+                        return Err(bad(
+                            cmd,
+                            format!(
+                                "the picks lie on {} bodies, {}, and at [{}, {}, {}] {} has an edge in the same place in its own component: {verb} each body in a command of its own, naming it with `body`",
+                                names.len(),
+                                and_list(&names, NAMED_BODIES),
+                                shown.x,
+                                shown.y,
+                                shown.z,
+                                b.name
+                            ),
+                        ));
+                    }
+                }
+            }
+            None
+        }
+    };
+    Ok(EdgePicks { points: out, body })
+}
+
+/// "A", "A and B", "A, B and C", and past `most` names "A, B and 3 more".
+fn and_list(names: &[String], most: usize) -> String {
+    let mut shown: Vec<String> = names.iter().take(most).cloned().collect();
+    if names.len() > most {
+        shown.push(format!("{} more", names.len() - most));
+    }
+    match shown.split_last() {
+        Some((last, rest)) if !rest.is_empty() => format!("{} and {last}", rest.join(", ")),
+        Some((last, _)) => last.clone(),
+        None => String::new(),
+    }
+}
+
+/// The distance from `q` to edge `index` of `body` on its exact curve, and the point there:
+/// samples, then a golden-section search between the best one's neighbours.
+fn edge_foot(body: &solidcraft_kernel::Body, index: usize, q: Vec3) -> Option<(f64, Vec3)> {
+    const SAMPLES: usize = 32;
+    const STEPS: usize = 40;
+    let e = body.record().edges.get(index)?;
+    let c = solidcraft_geom::brep::eval::CurveEval::new(e.parameters()).ok()?;
+    let [t0, t1] = e.interval;
+    if !(t0.is_finite() && t1.is_finite()) {
+        return None;
+    }
+    let at = |t: f64| c.point(t).map(|p| p.dist(q)).filter(|d| d.is_finite());
+    let step = (t1 - t0) / SAMPLES as f64;
+    let (k, _) = (0..=SAMPLES).filter_map(|k| Some((k, at(t0 + step * k as f64)?))).min_by(|a, b| a.1.total_cmp(&b.1))?;
+    let (mut lo, mut hi) = (t0 + step * k.saturating_sub(1) as f64, t0 + step * (k + 1).min(SAMPLES) as f64);
+    let ratio = (5.0_f64.sqrt() - 1.0) / 2.0;
+    for _ in 0..STEPS {
+        let (a, b) = (hi - ratio * (hi - lo), lo + ratio * (hi - lo));
+        if at(a).unwrap_or(f64::INFINITY) <= at(b).unwrap_or(f64::INFINITY) {
+            hi = b;
+        } else {
+            lo = a;
+        }
+    }
+    let foot = c.point((lo + hi) / 2.0)?;
+    let d = foot.dist(q);
+    d.is_finite().then_some((d, foot))
 }
 
 /// The direction an edge's polyline leaves `pt` in, when `pt` is one of its ends; `None` when
@@ -1680,7 +1971,11 @@ fn press_pull(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "solid.press_pull";
     let distance = req_expr(cmd, p, "distance")?;
     if p.get("edges").is_some() {
-        return fillet(s, &json!({"edges": p.get("edges"), "radius": distance}));
+        let mut q = json!({"edges": p.get("edges"), "radius": distance});
+        if let Some(body) = p.get("body").filter(|b| b.is_string()) {
+            q["body"] = body.clone();
+        }
+        return fillet(s, &q);
     }
     let face = p.get("face").ok_or_else(|| bad(cmd, "needs `face` or `edges`"))?;
     let d = s.doc.eval(&distance, Kind::Length).map_err(|e| bad(cmd, format!("distance: {e}")))?;
@@ -1730,7 +2025,7 @@ fn press_pull(s: &mut Session, p: &Value) -> Result<Value> {
 
 fn fillet(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "solid.fillet";
-    let edges = edge_points(s, p, cmd)?;
+    let picks = edge_points(s, p, cmd)?;
     let radius = req_expr(cmd, p, "radius")?;
     check_expr(s, &radius, Kind::Length, cmd, "radius")?;
     let style = match str_(p, "type").map(str::to_ascii_lowercase).as_deref() {
@@ -1833,9 +2128,9 @@ fn fillet(s: &mut Session, p: &Value) -> Result<Value> {
         s,
         p,
         FeatureKind::Fillet {
-            edges: edges.into_iter().map(Position).collect(),
+            edges: picks.points.into_iter().map(Position).collect(),
             radius,
-            body: str_(p, "body").map(BodyName::from),
+            body: picks.body.map(BodyName::from),
             style,
             fit,
             corner,
@@ -1859,7 +2154,7 @@ fn fillet(s: &mut Session, p: &Value) -> Result<Value> {
 
 fn chamfer(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "solid.chamfer";
-    let edges = edge_points(s, p, cmd)?;
+    let picks = edge_points(s, p, cmd)?;
     let distance = req_expr(cmd, p, "distance")?;
     check_expr(s, &distance, Kind::Length, cmd, "distance")?;
     let (distance2, angle) = (expr(p, "distance2"), expr(p, "angle"));
@@ -1877,12 +2172,12 @@ fn chamfer(s: &mut Session, p: &Value) -> Result<Value> {
         s,
         p,
         FeatureKind::Chamfer {
-            edges: edges.into_iter().map(Position).collect(),
+            edges: picks.points.into_iter().map(Position).collect(),
             distance,
             distance2,
             angle,
             flip,
-            body: str_(p, "body").map(BodyName::from),
+            body: picks.body.map(BodyName::from),
             tangent_chain: bool_(p, "tangent_chain").unwrap_or(true),
         },
     )

crates/engine/src/cmd/file.rs

@@ -39,7 +39,7 @@ pub static COMMANDS: &[CommandSpec] = &[
     CommandSpec::new("file.insert_mesh", "Insert Mesh", insert_mesh)
         .at("SOLID", "INSERT")
         .icon("import")
-        .params("path: .3mf, .stl, .obj, .ply (with faces), .glb or .gltf file (its meshes join the design as mesh bodies in a new component named after the file → component, component_name, occurrence; a glTF file's node tree becomes nested components held as one rigid group until component.unlock, a mesh placed again another occurrence, its materials the bodies' appearances, and its metres millimetres); name?; up?: z|y for a glTF file (default y: glTF has Y up, so the import's component is turned a quarter turn about X, Y becoming Z → stand_up: its occurrence; z: the file's axes are kept); units?: mm|cm|m|in|ft for an STL or OBJ file, or a PLY file with faces (default mm): the unit its coordinates are in, scaled to millimetres as the file is read (a 3MF or glTF file states its own). The design keeps the millimetre mesh and not the unit, so insert the file again to try another; origin?: bool (default false: the mesh keeps its file's coordinates; true: once read, scaled and stood up, the import's occurrence is moved so the box around its bodies is centred on X and Y of the active component with its lowest point on Z = 0 → moved_to_origin: [x, y, z], the shift made)"),
+        .params("path: .3mf, .stl, .obj, .ply (with faces), .glb or .gltf file (its meshes join the design as mesh bodies in a new component named after the file → component, component_name, occurrence; a glTF file's node tree becomes nested components held as one rigid group until component.unlock, a mesh placed again another occurrence, its materials the bodies' appearances, and its metres millimetres); name?; up?: z|y for a glTF file (default y: glTF has Y up, so the import's component is turned a quarter turn about X, Y becoming Z → stand_up: its occurrence; z: the file's axes are kept); units?: mm|cm|m|in|ft for an STL or OBJ file, or a PLY file with faces (default mm): the unit its coordinates are in, scaled to millimetres as the file is read (a 3MF or glTF file states its own). The design keeps the millimetre mesh and not the unit, so insert the file again to try another; origin?: bool (default false: the mesh keeps its file's coordinates; true: once read, scaled and stood up, the import's occurrence is moved so the box around its bodies is centred on X and Y of the active component with its lowest point on Z = 0 → moved_to_origin: [x, y, z], the shift made); crease_angle_degrees?: 0..180 (0 clears imported shading normals for the previous flat-shading behavior; positive angles regenerate angle-weighted normals across manifold edges below this crease angle; omitted keeps authored OBJ normals/smoothing groups, or flat shading when absent; geometry stays unchanged)"),
     CommandSpec::new("file.save", "Save", save)
         .icon("save")
         .key("Ctrl+S")
@@ -262,11 +262,19 @@ fn created_bodies(s: &Session, feature: u64) -> Vec<String> {
 /// Add a MeshImport feature for a 3MF, STL, OBJ or glTF file, in a new component named after the
 /// file. A glTF file's nodes become components in it, and its materials the bodies' looks; it is
 /// in metres with Y up, so unless `y_up` is false its component is turned to Z up (#1505).
-fn add_mesh(s: &mut Session, path: &str, name: Option<&str>, y_up: Option<bool>, unit: Option<(&'static str, f64)>, origin: bool) -> Result<Value> {
+fn add_mesh(
+    s: &mut Session,
+    path: &str,
+    name: Option<&str>,
+    y_up: Option<bool>,
+    unit: Option<(&'static str, f64)>,
+    origin: bool,
+    crease_angle: Option<f64>,
+) -> Result<Value> {
     let err = |e: solidcraft_io::IoError| EngineError::Other(format!("{path}: {e}"));
     let bytes = solidcraft_io::vfs::read(path, solidcraft_io::MAX_3MF_BYTES).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
     let gltf = solidcraft_io::is_gltf_path(path);
-    let (mf, plan, looks) = if gltf {
+    let (mut mf, plan, looks) = if gltf {
         let dir = std::path::Path::new(path).parent().map(std::path::Path::to_path_buf).unwrap_or_default();
         let mut load =
             |name: &str| solidcraft_io::vfs::read(&dir.join(name).to_string_lossy(), solidcraft_io::MAX_GLTF_BYTES).map_err(|e| e.to_string());
@@ -278,6 +286,19 @@ fn add_mesh(s: &mut Session, path: &str, name: Option<&str>, y_up: Option<bool>,
     } else {
         (solidcraft_io::mesh_import_feature_in(&bytes, path, unit.map_or(1.0, |(_, mm)| mm)).map_err(err)?, None, Vec::new())
     };
+    if let Some(angle) = crease_angle
+        && let solidcraft_doc::FeatureKind::MeshImport { meshes, .. } = &mut mf.kind
+    {
+        for mesh in meshes {
+            if angle == 0.0 {
+                // Keep the original flat display path, including its normalization
+                // and storage behavior, when the caller opts out of imported shading.
+                mesh.corner_normals = Default::default();
+            } else {
+                mesh.generate_crease_normals(angle).map_err(|e| bad("file.insert_mesh", e.to_string()))?;
+            }
+        }
+    }
     let fname = name.filter(|n| !n.trim().is_empty()).unwrap_or(&mf.name).to_string();
     let cname = import::component_name(path, name);
     let tree = match &plan {
@@ -365,7 +386,16 @@ fn insert_mesh(s: &mut Session, p: &Value) -> Result<Value> {
     }
     let up = mesh_up(p, path, cmd)?;
     let unit = mesh_units(p, path, cmd)?;
-    add_mesh(s, path, str_(p, "name"), up, unit, mesh_origin(p, cmd)?)
+    let crease_angle = match p.get("crease_angle_degrees") {
+        None | Some(Value::Null) => None,
+        Some(value) => Some(
+            value
+                .as_f64()
+                .filter(|v| v.is_finite() && (0.0..=180.0).contains(v))
+                .ok_or_else(|| bad(cmd, "crease_angle_degrees must be between 0 and 180 degrees"))?,
+        ),
+    };
+    add_mesh(s, path, str_(p, "name"), up, unit, mesh_origin(p, cmd)?, crease_angle)
 }
 
 /// `origin`: whether a mesh import is moved to the origin (#12543). Off unless asked, so a mesh
@@ -458,7 +488,7 @@ fn open(s: &mut Session, p: &Value) -> Result<Value> {
         let r = if solidcraft_io::is_step_path(path) {
             add_step(&mut fresh, path, None, &step_options(p, "doc.open")?)?
         } else {
-            add_mesh(&mut fresh, path, None, mesh_up(p, path, "doc.open")?, mesh_units(p, path, "doc.open")?, mesh_origin(p, "doc.open")?)?
+            add_mesh(&mut fresh, path, None, mesh_up(p, path, "doc.open")?, mesh_units(p, path, "doc.open")?, mesh_origin(p, "doc.open")?, None)?
         };
         // The design is the file: its component is the one being worked in.
         if let Some(c) = r["component"].as_u64() {
@@ -834,7 +864,7 @@ fn saved_preview(s: &Session) -> Option<solidcraft_io::DesignPreview> {
     for body in &world.bodies {
         let mesh = body.cached_mesh()?;
         bytes =
-            bytes.saturating_add(mesh.positions.len().saturating_mul(24)).saturating_add(mesh.triangles.len().saturating_mul(12)).saturating_add(24);
+            bytes.saturating_add(mesh.positions.len().saturating_mul(24)).saturating_add(mesh.triangles.len().saturating_mul(84)).saturating_add(32);
         triangles = triangles.saturating_add(mesh.triangles.len());
         if bytes > 8 << 20 || triangles > 100_000 {
             return None;
@@ -844,6 +874,7 @@ fn saved_preview(s: &Session) -> Option<solidcraft_io::DesignPreview> {
             positions: mesh.positions.iter().flat_map(|p| [p.x, p.y, p.z]).collect(),
             triangles: mesh.triangles.iter().flatten().copied().collect(),
             color: s.doc.body_color(body),
+            corner_normals: mesh.triangles.iter().flatten().filter_map(|&i| mesh.normals.get(i as usize)).flat_map(|n| [n.x, n.y, n.z]).collect(),
         });
     }
     Some(preview)
@@ -1393,13 +1424,18 @@ mod tests {
             assert_eq!(r["bytes"].as_u64(), Some(bytes.len() as u64), "{cmd}");
             assert!(bytes.starts_with(signature), "{cmd}");
         }
-        // The triangles `file.export` writes (the 80-byte header holds the file's name): a box is
-        // 12 triangles, 84 + 50 bytes each.
+        // The triangles `file.export` writes (the 80-byte header holds the file's name), 84 + 50
+        // bytes each. The mesher lays each planar face out as a regular grid whose sides are at
+        // most a fifth of the body's diagonal (kernel test `a_box_is_a_regular_grid_on_every_face`):
+        // 22.9 / 5 = 4.58 mm, so 5 × 3 × 2 cells along 20 × 10 × 5, two triangles each.
         s.execute("file.export", &json!({"path": at("box.stl")})).unwrap();
         assert_eq!(std::fs::read(at("StlBinary.txt")).unwrap()[80..], std::fs::read(at("box.stl")).unwrap()[80..]);
-        assert_eq!(std::fs::metadata(at("box.stl")).unwrap().len(), 84 + 50 * 12);
+        let triangles = 2 * 2 * (5 * 3 + 5 * 2 + 3 * 2);
+        let stl = std::fs::read(at("box.stl")).unwrap();
+        assert_eq!(u32::from_le_bytes([stl[80], stl[81], stl[82], stl[83]]), u32::try_from(triangles).unwrap());
+        assert_eq!(stl.len(), 84 + 50 * triangles);
         let obj = std::fs::read_to_string(at("Obj.txt")).unwrap();
-        assert_eq!(obj.lines().filter(|l| l.starts_with("f ")).count(), 12, "{obj}");
+        assert_eq!(obj.lines().filter(|l| l.starts_with("f ")).count(), triangles, "{obj}");
         let r = s.execute("file.export_urdf", &json!({"path": at("robot.urdf")})).unwrap();
         assert_eq!(r["format"], "Urdf");
         assert!(std::fs::read_to_string(at("robot.urdf")).unwrap().contains("<robot"));
@@ -1978,6 +2014,95 @@ mod tests {
         std::fs::remove_file(path).unwrap();
     }
 
+    #[test]
+    fn mesh_import_explicit_crease_normals_are_undoable_and_survive_cached_reopen() {
+        let dir = std::env::temp_dir().join(format!("solidcraft-mesh-normals-{}", std::process::id()));
+        std::fs::create_dir_all(&dir).unwrap();
+        let path = dir.join("fold.obj");
+        std::fs::write(&path, "v 0 0 0\nv 1 0 0\nv 0 1 0\nv 0 -0.8660254037844386 0.5\nf 1 2 3\nf 2 1 4\n").unwrap();
+        let mut session = Session::default();
+        let before = session.doc.to_json();
+        for bad_angle in [json!(-1), json!(181), json!("smooth")] {
+            let result = session.execute("file.insert_mesh", &json!({"path":path, "crease_angle_degrees":bad_angle}));
+            assert!(result.unwrap_err().to_string().contains("crease_angle_degrees"));
+            assert_eq!(session.doc.to_json(), before);
+        }
+        session.execute("file.insert_mesh", &json!({"path":path, "crease_angle_degrees":40})).unwrap();
+        let normals = |s: &Session| s.model.state().bodies[0].mesh().normals.clone();
+        let expected = normals(&session);
+        assert!(expected[0].y > 0.2 && expected[0].z > 0.9);
+        session.execute("edit.undo", &json!({})).unwrap();
+        assert!(session.model.state().bodies.is_empty());
+        session.execute("edit.redo", &json!({})).unwrap();
+        assert_eq!(normals(&session), expected);
+        let bytes = session.design_container(solidcraft_io::DesignCompression::Fast, false, true).unwrap();
+        let cached = solidcraft_io::read_design_geometry(&bytes).expect("shaded mesh retains native cache");
+        assert!(!cached.bodies[0].body.triangle_corner_normals().unwrap().is_empty());
+        let saved_path = dir.join("shaded.sc");
+        std::fs::write(&saved_path, &bytes).unwrap();
+        let mut reopened = Session::default();
+        reopened.execute("doc.open", &json!({"path":saved_path})).unwrap();
+        assert_eq!(normals(&reopened), expected);
+        let doc = solidcraft_io::read_design(&bytes).unwrap();
+        let cold = Session::new(doc);
+        assert_eq!(normals(&cold), expected);
+        std::fs::remove_dir_all(dir).unwrap();
+    }
+
+    #[test]
+    fn mesh_import_zero_crease_restores_legacy_flat_shading_and_survives_reopen() {
+        let dir = std::env::temp_dir().join(format!("solidcraft-obj-flat-{}", std::process::id()));
+        std::fs::create_dir_all(&dir).unwrap();
+        let vertices = "v 0 0 0\nv 1 0 0\nv 0 1 0\nv 0 -0.8660254037844386 0.5\n";
+        let faces = "f 1 2 3\nf 2 1 4\n";
+        let reference_path = dir.join("reference.obj");
+        std::fs::write(&reference_path, format!("{vertices}{faces}")).unwrap();
+        let mut reference = Session::default();
+        reference.execute("file.insert_mesh", &json!({"path":reference_path})).unwrap();
+        let display = |s: &Session| {
+            let mesh = s.model.state().bodies[0].mesh();
+            (mesh.positions.clone(), mesh.triangles.clone(), mesh.normals.clone())
+        };
+        let expected = display(&reference);
+        for (name, source) in
+            [("groups", format!("{vertices}s 1\n{faces}")), ("authored", format!("{vertices}vn 0 1 1\nf 1//1 2//1 3//1\nf 2//1 1//1 4//1\n"))]
+        {
+            let path = dir.join(format!("{name}.obj"));
+            std::fs::write(&path, source).unwrap();
+            let mut annotated = Session::default();
+            annotated.execute("file.insert_mesh", &json!({"path":path})).unwrap();
+            assert_ne!(display(&annotated).2, expected.2, "{name} must exercise imported shading");
+            let mut session = Session::default();
+            session.execute("file.insert_mesh", &json!({"path":path, "crease_angle_degrees":0})).unwrap();
+            assert_eq!(display(&session), expected, "{name} uses the exact former flat display path");
+            let meshes = session
+                .doc
+                .features
+                .iter()
+                .find_map(|f| match &f.kind {
+                    solidcraft_doc::FeatureKind::MeshImport { meshes, .. } => Some(meshes),
+                    _ => None,
+                })
+                .unwrap();
+            assert!(meshes.iter().all(|mesh| mesh.corner_normals.is_empty()));
+            session.execute("edit.undo", &json!({})).unwrap();
+            assert!(session.model.state().bodies.is_empty());
+            session.execute("edit.redo", &json!({})).unwrap();
+            assert_eq!(display(&session), expected);
+            let bytes = session.design_container(solidcraft_io::DesignCompression::Fast, false, true).unwrap();
+            let cached = solidcraft_io::read_design_geometry(&bytes).unwrap();
+            assert!(cached.bodies[0].body.triangle_corner_normals().unwrap().is_empty());
+            let saved_path = dir.join(format!("{name}.sc"));
+            std::fs::write(&saved_path, &bytes).unwrap();
+            let mut reopened = Session::default();
+            reopened.execute("doc.open", &json!({"path":saved_path})).unwrap();
+            assert_eq!(display(&reopened), expected);
+            let cold = Session::new(solidcraft_io::read_design(&bytes).unwrap());
+            assert_eq!(display(&cold), expected);
+        }
+        std::fs::remove_dir_all(dir).unwrap();
+    }
+
     /// #9170: a design holding a mesh body (an inserted STL) keeps its saved model and opens from
     /// it. One mesh body left the cache out for the whole model, so every feature, the boxes
     /// too, was evaluated again on opening.

crates/engine/src/cmd/frame.rs

@@ -6,7 +6,7 @@
 use solidcraft_geom::prelude::*;
 use std::collections::BTreeMap;
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcore_record::{Loop2, Seg2, Vec2};
 use solidcraft_doc::expr::Kind;
 use solidcraft_doc::frame::{self, Anchor, MemberProfile, Profile, ProfileSpec};
@@ -17,12 +17,23 @@ use super::features::{add_feature, check_expr, sketch_id};
 use super::sketch::edit;
 use super::{CommandSpec, in_sketch, not_in_sketch};
 use crate::params::{bad, bool_, expr, num, str_, string_list, vec2};
+use crate::schema::features::FeatureResult;
+use crate::schema::frame::{
+    CreatedIds, FrameMemberParams, ProfileInsertParams, ProfileInsertResult, ProfileKindInfo, ProfileListParams, ProfileListResult, ProfileOut,
+    ProfilePropertiesParams, ProfilePropertiesResult, ProfileSection,
+};
+use crate::schema::{TypedContract, output_schema_for};
 use crate::{Result, Session};
 
 #[cfg(test)]
 #[path = "frame_tests.rs"]
 mod tests;
 
+const MEMBER_CONTRACT: TypedContract<FrameMemberParams> = TypedContract::new();
+const LIST_CONTRACT: TypedContract<ProfileListParams> = TypedContract::new();
+const PROPERTIES_CONTRACT: TypedContract<ProfilePropertiesParams> = TypedContract::new();
+const INSERT_CONTRACT: TypedContract<ProfileInsertParams> = TypedContract::new();
+
 /// The profile parameter, as every frame command documents it.
 macro_rules! profile_doc {
     () => {
@@ -31,20 +42,40 @@ macro_rules! profile_doc {
 }
 
 pub static COMMANDS: &[CommandSpec] = &[
-    CommandSpec::new("frame.member", "Frame Member", member).at("WELDMENTS", "CREATE").icon("frame_member").enabled(not_in_sketch).params(concat!(
+    CommandSpec::new("frame.member", "Frame Member", crate::checked!("frame.member", member))
+        .at("WELDMENTS", "CREATE")
+        .icon("frame_member")
+        .enabled(not_in_sketch)
+        .contract(&MEMBER_CONTRACT)
+        .output(output_schema_for::<FeatureResult>)
+        .params(concat!(
         "sketch: the frame sketch (id or name; 2D or 3D); lines?: [curve ids] (one member each; default: every straight line drawn in the sketch: not construction, not projected or otherwise linked, not of no length); ",
         profile_doc!(),
         " | profile_sketch: a sketch whose profile is the section, in its own x and y around its origin, with profiles?: picks as solid.extrude takes them (default: its material, nested loops alternating, so two circles make a tube); anchor?: origin|center|centroid|top_left|top|top_right|left|right|bottom_left|bottom|bottom_right (the profile point that sits on each line, default origin); angle?: angle expr (the profile turned about the line; default 0: its y as near world up as the line allows, a vertical member's x along world X); mirror?: bool (the profile mirrored across its y axis); name?; body_name? (what the members are named after, then numbered: `Rail`, `Rail (2)`…; default the profile's description, `Rect Tube 40x40x3`, or the profile sketch's name); names?: {line id: name} (names to keep, as Edit Feature keeps them). One body per line, from its start to its end; each member keeps its name when other lines are added or deleted. Returns the feature and the bodies it made"
     )),
-    CommandSpec::new("frame.profile.list", "Profile Library", list).icon("library")
+    CommandSpec::new("frame.profile.list", "Profile Library", crate::checked!("frame.profile.list", list))
+        .icon("library")
         .noundo()
         .doc_only()
+        .contract(&LIST_CONTRACT)
+        .output(output_schema_for::<ProfileListResult>)
         .params("Returns kinds: [{kind, label, required, optional, example}]: the built-in profiles, each SolidCraft's own parametric definition"),
-    CommandSpec::new("frame.profile.properties", "Profile Properties", properties).icon("measure").noundo().doc_only().params(concat!(
+    CommandSpec::new("frame.profile.properties", "Profile Properties", crate::checked!("frame.profile.properties", properties))
+        .icon("measure")
+        .noundo()
+        .doc_only()
+        .contract(&PROPERTIES_CONTRACT)
+        .output(output_schema_for::<ProfilePropertiesResult>)
+        .params(concat!(
         profile_doc!(),
         "; density?: kg/m³ (adds mass_per_m, kg/m). Returns profile (every default filled in), area (mm²), centroid [x,y] (mm, from the bounding box centre), ixx, iyy, ixy (mm⁴ about the centroid), width, height"
     )),
-    CommandSpec::new("frame.profile.insert", "Insert Profile", insert).icon("import").enabled(in_sketch).params(concat!(
+    CommandSpec::new("frame.profile.insert", "Insert Profile", crate::checked!("frame.profile.insert", insert))
+        .icon("import")
+        .enabled(in_sketch)
+        .contract(&INSERT_CONTRACT)
+        .output(output_schema_for::<ProfileInsertResult>)
+        .params(concat!(
         profile_doc!(),
         "; at?: [x,y] (sketch mm, default the origin); anchor?: origin|center|centroid|top_left|top|top_right|left|right|bottom_left|bottom|bottom_right (the profile point placed on `at`: its origin, the default and a built-in profile's centre, its bounding box's centre, its centroid, or a corner or edge middle of its bounding box); angle?: radians, counter-clockwise; fixed?: bool (default true: the curves are locked, so solving the sketch keeps the shape); sketch?: id|name (default: the sketch being edited). Returns the section as frame.profile.properties does",
         created_doc!()
@@ -73,29 +104,32 @@ fn profile(s: &Session, cmd: &str, p: &Value) -> Result<Profile> {
     resolve(s, cmd, &profile_spec(cmd, p)?)
 }
 
+/// A frame command's reply, built from its schema's type so the two can't drift apart.
+fn frame_reply(cmd: &str, r: impl serde::Serialize) -> Result<Value> {
+    serde_json::to_value(r).map_err(|e| bad(cmd, e.to_string()))
+}
+
 fn list(_: &mut Session, _: &Value) -> Result<Value> {
-    Ok(json!({"kinds": frame::profile_kinds()}))
+    let kinds = frame::profile_kinds().iter().map(ProfileKindInfo::from).collect();
+    frame_reply("frame.profile.list", ProfileListResult { kinds, param_warnings: Vec::new() })
 }
 
 /// The profile's section as the commands report it.
-fn section_json(cmd: &str, profile: &Profile, density: Option<f64>) -> Result<Value> {
+fn section(cmd: &str, profile: &Profile, density: Option<f64>) -> Result<ProfileSection> {
     let region = profile.region().map_err(|e| bad(cmd, e.to_string()))?;
     let s = frame::section(&region);
-    let mut out = json!({
-        "profile": profile.filled(),
-        "area": s.area,
-        "centroid": s.centroid,
-        "ixx": s.ixx,
-        "iyy": s.iyy,
-        "ixy": s.ixy,
-        "width": s.width,
-        "height": s.height,
-    });
-    if let (Some(rho), Some(o)) = (density, out.as_object_mut()) {
+    Ok(ProfileSection {
+        profile: ProfileOut(profile.filled()),
+        area: s.area,
+        centroid: s.centroid,
+        ixx: s.ixx,
+        iyy: s.iyy,
+        ixy: s.ixy,
+        width: s.width,
+        height: s.height,
         // mm² × 1e-6 m²/mm² × kg/m³ = kg/m.
-        o.insert("mass_per_m".into(), json!(s.area * 1e-6 * rho));
-    }
-    Ok(out)
+        mass_per_m: density.map(|rho| s.area * 1e-6 * rho),
+    })
 }
 
 fn properties(s: &mut Session, p: &Value) -> Result<Value> {
@@ -109,7 +143,7 @@ fn properties(s: &mut Session, p: &Value) -> Result<Value> {
                 .ok_or_else(|| bad(cmd, "`density` must be a positive number of kg/m³ (at most 1e6)"))?,
         ),
     };
-    section_json(cmd, &profile, density)
+    frame_reply(cmd, ProfilePropertiesResult { section: section(cmd, &profile, density)?, param_warnings: Vec::new() })
 }
 
 fn insert(s: &mut Session, p: &Value) -> Result<Value> {
@@ -135,15 +169,16 @@ fn insert(s: &mut Session, p: &Value) -> Result<Value> {
     };
     let region = profile.region().map_err(|e| bad(cmd, e.to_string()))?;
     let placed = frame::placed(&region, frame::anchor_point(std::slice::from_ref(&region), anchor), at, angle);
-    let section = section_json(cmd, &profile, None)?;
+    let section = section(cmd, &profile, None)?;
     let (created, info) = edit(s, p, cmd, false, |sk, _| {
         let before = sk.clone();
         for l in std::iter::once(&placed.outer).chain(&placed.holes) {
             add_loop(sk, l, fixed, cmd)?;
         }
-        Ok(super::sketch_created(Some(&before), sk))
+        serde_json::from_value::<CreatedIds>(super::sketch_created(Some(&before), sk)).map_err(|e| bad(cmd, e.to_string()))
     })?;
-    Ok(json!({"created": created, "section": section, "sketch": info}))
+    let sketch = serde_json::from_value(info).map_err(|e| bad(cmd, e.to_string()))?;
+    frame_reply(cmd, ProfileInsertResult { created, section, sketch, param_warnings: Vec::new() })
 }
 
 /// Draw the closed loop `l` (lines and arcs) into the sketch, each segment sharing its end

crates/engine/src/cmd/inspect.rs

@@ -12,13 +12,25 @@ use solidcraft_sketch::CurveKind;
 use super::CommandSpec;
 use crate::params::{bad, bool_, str_, string_list};
 use crate::schema::inspect::{
-    BodyListParams, FaceCylinder, ModelEdge, ModelEdges, ModelFace, ModelFaces, ModelThread, ModelThreads, ModelThreadsParams,
+    BodyFailure, BodyFeaturesParams, BodyFigures, BodyListParams, BodyMeasurement, BodyName, BodyNames, BodyOutcome, BoundingBox, CommandEntry,
+    CommandsParams, CurveShape, DocumentBody, DocumentBodyDetail, DocumentInspectParams, DocumentInspectResult, DocumentParam, DocumentSketch,
+    FaceCylinder, KernelCounts, ListedMaterial, MaterialAssignParams, MaterialAssignResult, MaterialListParams, MaterialListResult, MeasureParams,
+    MeasureResult, MeasureTotal, Measured, MeasuredBodies, MeasuredBody, ModelBodyFeatures, ModelEdge, ModelEdges, ModelFace, ModelFaces,
+    ModelThread, ModelThreads, ModelThreadsParams, SketchConstraint, SketchCurve, SketchInspectParams, SketchInspected, SketchPoint, SketchProfile,
+    SketchWire, TimelineEntry, WireArcInfo,
 };
 use crate::schema::{TypedContract, output_schema_for};
 use crate::{EngineError, Result, Session};
 
 const BODY_LIST_CONTRACT: TypedContract<BodyListParams> = TypedContract::new();
 const THREADS_CONTRACT: TypedContract<ModelThreadsParams> = TypedContract::new();
+const BODY_FEATURES_CONTRACT: TypedContract<BodyFeaturesParams> = TypedContract::new();
+const MEASURE_CONTRACT: TypedContract<MeasureParams> = TypedContract::new();
+const DOCUMENT_INSPECT_CONTRACT: TypedContract<DocumentInspectParams> = TypedContract::new();
+const SKETCH_INSPECT_CONTRACT: TypedContract<SketchInspectParams> = TypedContract::new();
+const MATERIAL_ASSIGN_CONTRACT: TypedContract<MaterialAssignParams> = TypedContract::new();
+const MATERIAL_LIST_CONTRACT: TypedContract<MaterialListParams> = TypedContract::new();
+const COMMANDS_CONTRACT: TypedContract<CommandsParams> = TypedContract::new();
 
 #[path = "appearance_chain.rs"]
 mod appearance_chain;
@@ -26,23 +38,39 @@ mod appearance_chain;
 #[path = "appearance_gestures.rs"]
 pub(super) mod appearance_gestures;
 
+#[path = "body_features.rs"]
+mod body_features;
+
 pub static COMMANDS: &[CommandSpec] = &[
     CommandSpec::new("inspect.colored_components", "Component Colors", colored_components)
         .at("SOLID", "INSPECT").icon("colored_components").noundo()
         .params("enabled?: bool (omitted: toggle); temporary component colours, without changing appearances"),
-    CommandSpec::new("inspect.measure", "Measure", measure)
+    CommandSpec::new("inspect.measure", "Measure", crate::checked!("inspect.measure", measure))
         .at("SOLID", "INSPECT")
         .icon("measure")
         .key("I")
         .noundo()
+        .contract(&MEASURE_CONTRACT)
+        .output(output_schema_for::<MeasureResult>)
         .params("bodies?: [names] (default all); names_only?: bool (each world body's name and its definition's, nothing measured) → closed per body; volume_mm3, center_of_mass, density_g_cm3 and mass_g only for closed, consistently oriented bodies; area, bbox and counts for all; total.open_bodies_skipped counts bodies excluded from volume/mass totals; or items: [1-2 selections] (face/edge: type, body, point; index optional) → length/area/volume; diameter, radius, circumference or arc_length/angle_deg of circles, arcs and cylinders; slot sizes; min (distance_mm, from, to), max, center_distance (centre to centre, or from an axis) and angle"),
-    CommandSpec::new("document.inspect", "Inspect Design", inspect).icon("inspect").noundo().params("measure?: bool (include body measurements); sketch_counts?: bool (each sketch also gives its plane and its number of points and constraints)"),
+    CommandSpec::new("document.inspect", "Inspect Design", crate::checked!("document.inspect", inspect))
+        .icon("inspect")
+        .noundo()
+        .contract(&DOCUMENT_INSPECT_CONTRACT)
+        .output(output_schema_for::<DocumentInspectResult>)
+        .params("measure?: bool (include body measurements); sketch_counts?: bool (each sketch also gives its plane and its number of points and constraints)"),
     CommandSpec::new("document.revision", "Design Revision", revision).icon("inspect").noundo().params(
         "→ document_id (this open design's id: kept while it stays open, another for each design started or opened), \
          revision (moves whenever the design, what is hidden or a component's uncaptured position changes, \
          never on a selection or a view; from one counter for the whole run, so it never repeats). Read-only",
     ),
-    CommandSpec::new("sketch.inspect", "Inspect Sketch", sketch_inspect).at("SKETCH", "INSPECT").icon("inspect").noundo().params("sketch?: id|name (default active)"),
+    CommandSpec::new("sketch.inspect", "Inspect Sketch", crate::checked!("sketch.inspect", sketch_inspect))
+        .at("SKETCH", "INSPECT")
+        .icon("inspect")
+        .noundo()
+        .contract(&SKETCH_INSPECT_CONTRACT)
+        .output(output_schema_for::<SketchInspected>)
+        .params("sketch?: id|name (default active)"),
     CommandSpec::new("model.edges", "List Edges", crate::checked!("model.edges", model_edges))
         .icon("inspect")
         .noundo()
@@ -65,9 +93,20 @@ pub static COMMANDS: &[CommandSpec] = &[
         .noundo()
         .contract(&THREADS_CONTRACT)
         .output(output_schema_for::<ModelThreads>),
-    CommandSpec::new("material.assign", "Physical Material", physical_material)
+    CommandSpec::new("model.body_features", "List Body Features", crate::checked!("model.body_features", body_features::model_body_features))
+        .icon("inspect")
+        .noundo()
+        .contract(&BODY_FEATURES_CONTRACT)
+        .output(output_schema_for::<ModelBodyFeatures>)
+        .params(
+            "body?: name (a placed copy's name means the body it shows; default every body) → bodies: [{body, features: [{id, name}]}], \
+             in timeline order the feature that created each body, every later one that changed it, and those of bodies consumed into it. Read-only",
+        ),
+    CommandSpec::new("material.assign", "Physical Material", crate::checked!("material.assign", physical_material))
         .at("SOLID", "MODIFY")
         .icon("material")
+        .contract(&MATERIAL_ASSIGN_CONTRACT)
+        .output(output_schema_for::<MaterialAssignResult>)
         .params("bodies: [names]; material: name (Steel, Aluminum, ABS Plastic, …, or one made with material.create; `material.list`)"),
     CommandSpec::new("appearance.assign", "Appearance", crate::checked!("appearance.assign", appearance))
         .at("SOLID", "MODIFY")
@@ -104,11 +143,18 @@ pub static COMMANDS: &[CommandSpec] = &[
         .contract(&LIST_CONTRACT)
         .output(crate::schema::output_schema_for::<AppearanceListResult>)
         .params("body?: name (or a placed copy's, `KB (K:2)`: the body it shows) → assigned appearances; with body, its resolved look and its faces' (face index, look)"),
-    CommandSpec::new("material.list", "List Materials", material_list).icon("list")
+    CommandSpec::new("material.list", "List Materials", crate::checked!("material.list", material_list))
+        .icon("list")
         .noundo()
         .doc_only()
+        .contract(&MATERIAL_LIST_CONTRACT)
+        .output(output_schema_for::<MaterialListResult>)
         .params("→ built-in and design-owned materials (user: true, look, optional physical_card/physical_validation/density_comparison). Read-only; candidate engineering records do not certify sources or supply a solver"),
-    CommandSpec::new("engine.commands", "List Commands", commands).icon("list").noundo(),
+    CommandSpec::new("engine.commands", "List Commands", crate::checked!("engine.commands", commands))
+        .icon("list")
+        .noundo()
+        .contract(&COMMANDS_CONTRACT)
+        .output(output_schema_for::<Vec<CommandEntry>>),
     CommandSpec::new("engine.describe", "Describe Command", crate::checked!("engine.describe", describe))
         .icon("list")
         .noundo()
@@ -128,7 +174,7 @@ pub(crate) fn encloses_volume(body: &solidcraft_kernel::Body) -> bool {
 }
 
 pub fn measure_json(b: &solidcraft_doc::ModelBody) -> Value {
-    measure_sheet_json(b, None)
+    serde_json::to_value(measure_sheet(b, None)).unwrap_or_default()
 }
 
 pub(super) fn measure_body(
@@ -150,27 +196,53 @@ pub(super) fn measure_body(
     Ok(measured)
 }
 
-fn measure_sheet_json(b: &solidcraft_doc::ModelBody, definitions: Option<&solidcraft_doc::ModelState>) -> Value {
+fn measure_sheet(b: &solidcraft_doc::ModelBody, definitions: Option<&solidcraft_doc::ModelState>) -> BodyMeasurement {
+    let name = b.name.clone();
     match measure_body(b, definitions) {
         Ok(m) => {
             let closed = encloses_volume(&b.body);
-            json!({
-                "name": b.name,
-                "closed": closed,
-                "volume_mm3": closed.then_some(m.volume),
-                "area_mm2": m.area,
-                "center_of_mass": closed.then_some(m.centroid),
-                "bbox": {"min": m.bbox.min, "max": m.bbox.max},
-                "faces": m.merged.faces,
-                "edges": m.merged.edges,
-                "vertices": m.merged.vertices,
-                "face_types": m.merged.face_types,
-                "kernel": {"faces": m.faces, "edges": m.edges, "vertices": m.vertices, "shells": m.shells},
-                "measured_by": m.measured_by,
-                "notes": m.notes,
-            })
+            let outcome = BodyOutcome::Measured(BodyFigures {
+                closed,
+                volume_mm3: closed.then_some(m.volume),
+                area_mm2: m.area,
+                center_of_mass: closed.then(|| m.centroid.into()),
+                bbox: BoundingBox { min: m.bbox.min.into(), max: m.bbox.max.into() },
+                faces: count(m.merged.faces),
+                edges: count(m.merged.edges),
+                vertices: count(m.merged.vertices),
+                face_types: m.merged.face_types,
+                kernel: KernelCounts { faces: m.faces, edges: m.edges, vertices: m.vertices, shells: m.shells },
+                measured_by: m.measured_by.to_string(),
+                notes: m.notes,
+            });
+            BodyMeasurement { name, outcome }
+        }
+        Err(e) => measure_failed(name, e.to_string()),
+    }
+}
+
+fn measure_failed(name: String, error: String) -> BodyMeasurement {
+    BodyMeasurement { name, outcome: BodyOutcome::Failed(BodyFailure { error, faces: None, edges: None, vertices: None }) }
+}
+
+/// A topology count as the replies give it.
+fn count(n: usize) -> i64 {
+    i64::try_from(n).unwrap_or(0)
+}
+
+/// A reply as JSON: the commands build their replies from the types their output schemas
+/// describe, so the two can't drift apart.
+fn typed_reply(cmd: &str, reply: impl serde::Serialize) -> Result<Value> {
+    serde_json::to_value(reply).map_err(|e| bad(cmd, e.to_string()))
+}
+
+impl BodyMeasurement {
+    /// The volume, when the body has one that is a number.
+    fn volume(&self) -> Option<f64> {
+        match &self.outcome {
+            BodyOutcome::Measured(f) => f.volume_mm3.filter(|v| v.is_finite()),
+            BodyOutcome::Failed(_) => None,
         }
-        Err(e) => json!({"name": b.name, "error": e.to_string()}),
     }
 }
 
@@ -187,138 +259,217 @@ fn measure(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad(cmd, "unknown body name"));
     }
     if bool_(p, "names_only").unwrap_or(false) {
-        let bodies: Vec<_> = selected.iter().map(|b| json!({"name": b.name, "definition": b.definition_name()})).collect();
-        return Ok(json!({"body_count": bodies.len(), "bodies": bodies}));
+        let bodies: Vec<_> = selected.iter().map(|b| BodyName { name: b.name.clone(), definition: b.definition_name().to_string() }).collect();
+        let measured = Measured::Names(BodyNames { body_count: bodies.len(), bodies });
+        return typed_reply(cmd, MeasureResult { measured, param_warnings: Vec::new() });
     }
     // Each body is measured on its own: on all cores, in body order.
-    let mut bodies: Vec<Value> = solidcraft_kernel::map_on_threads(&selected, 16, |b| measure_sheet_json(b, Some(&definitions)))
+    let measurements: Vec<BodyMeasurement> = solidcraft_kernel::map_on_threads(&selected, 16, |b| measure_sheet(b, Some(&definitions)))
         .into_iter()
         .zip(&selected)
-        .map(|(m, b)| m.unwrap_or_else(|| json!({"name": b.name, "error": "measuring this body failed"})))
+        .map(|(m, b)| m.unwrap_or_else(|| measure_failed(b.name.clone(), "measuring this body failed".into())))
         .collect();
     // Mass from each body's material.
-    for (b, body) in bodies.iter_mut().zip(selected) {
+    let mut bodies: Vec<MeasuredBody> = Vec::with_capacity(measurements.len());
+    for (measurement, body) in measurements.into_iter().zip(selected) {
         let source = body.definition_name();
         // Every body's material, measured or not: naming it takes no measuring.
-        b["material"] = json!(s.doc.body_material(source));
-        if let Some(v) = b["volume_mm3"].as_f64() {
+        let mut b = MeasuredBody { measurement, material: s.doc.body_material(source), density_g_cm3: None, mass_g: None, sheet_metal: None };
+        if let Some(v) = b.measurement.volume() {
             let rho = s.doc.density(source);
-            b["density_g_cm3"] = json!(rho);
-            b["mass_g"] = json!(v * rho / 1000.0);
+            b.density_g_cm3 = Some(rho);
+            b.mass_g = Some(v * rho / 1000.0);
         }
         // Only Measure exposes sheet boundary counts; document.inspect keeps kernel counts.
         if let Some(sheet) = definitions.sheets.iter().find(|sheet| sheet.body == source) {
             let (df, de, dv) = sheet.round_hole_correction();
-            for (key, delta) in [("faces", df), ("edges", de), ("vertices", dv)] {
-                b[key] = json!(b["kernel"][key].as_i64().unwrap_or(0) + delta);
+            match &mut b.measurement.outcome {
+                BodyOutcome::Measured(f) => {
+                    f.faces = count(f.kernel.faces) + df;
+                    f.edges = count(f.kernel.edges) + de;
+                    f.vertices = count(f.kernel.vertices) + dv;
+                }
+                BodyOutcome::Failed(x) => (x.faces, x.edges, x.vertices) = (Some(df), Some(de), Some(dv)),
             }
-            b["sheet_metal"] = json!(true);
+            b.sheet_metal = Some(true);
+        }
+        bodies.push(b);
+    }
+    fn figures(b: &MeasuredBody) -> Option<&BodyFigures> {
+        match &b.measurement.outcome {
+            BodyOutcome::Measured(f) => Some(f),
+            BodyOutcome::Failed(_) => None,
         }
     }
-    let skipped = bodies.iter().filter(|b| b["closed"] == false).count();
-    let tv: f64 = bodies.iter().filter_map(|b| b["volume_mm3"].as_f64()).sum();
-    let ta: f64 = bodies.iter().filter_map(|b| b["area_mm2"].as_f64()).sum();
-    let tf: u64 = bodies.iter().filter_map(|b| b["faces"].as_u64()).sum();
-    let te: u64 = bodies.iter().filter_map(|b| b["edges"].as_u64()).sum();
-    let tvx: u64 = bodies.iter().filter_map(|b| b["vertices"].as_u64()).sum();
-    let tm: f64 = bodies.iter().filter_map(|b| b["mass_g"].as_f64()).sum();
-    Ok(
-        json!({"body_count": bodies.len(), "bodies": bodies, "total": {"open_bodies_skipped": skipped, "volume_mm3": tv, "area_mm2": ta, "mass_g": tm, "faces": tf, "edges": te, "vertices": tvx}}),
+    let counted = |n: Option<i64>| n.and_then(|n| u64::try_from(n).ok());
+    let faces = |b: &MeasuredBody| match &b.measurement.outcome {
+        BodyOutcome::Measured(f) => (counted(Some(f.faces)), counted(Some(f.edges)), counted(Some(f.vertices))),
+        BodyOutcome::Failed(x) => (counted(x.faces), counted(x.edges), counted(x.vertices)),
+    };
+    let total = MeasureTotal {
+        open_bodies_skipped: bodies.iter().filter(|b| figures(b).is_some_and(|f| !f.closed)).count(),
+        volume_mm3: bodies.iter().filter_map(|b| b.measurement.volume()).sum(),
+        area_mm2: bodies.iter().filter_map(|b| figures(b)).map(|f| f.area_mm2).filter(|a| a.is_finite()).sum(),
+        mass_g: bodies.iter().filter_map(|b| b.mass_g).filter(|m| m.is_finite()).sum(),
+        faces: bodies.iter().filter_map(|b| faces(b).0).sum(),
+        edges: bodies.iter().filter_map(|b| faces(b).1).sum(),
+        vertices: bodies.iter().filter_map(|b| faces(b).2).sum(),
+    };
+    typed_reply(
+        cmd,
+        MeasureResult { measured: Measured::Bodies(MeasuredBodies { body_count: bodies.len(), bodies, total }), param_warnings: Vec::new() },
     )
 }
 
+/// A 2D position as the replies give it.
+fn at2(p: solidcore_record::Vec2) -> [f64; 2] {
+    [p.x, p.y]
+}
+
 /// Sketch `id`, placed where the placed model `world` has it (its component's placement).
-fn sketch_json(s: &Session, world: &solidcraft_doc::ModelState, id: u64) -> Option<Value> {
+fn sketch_json(s: &Session, world: &solidcraft_doc::ModelState, id: u64) -> Option<SketchInspected> {
     let state = s.model.state();
     let ss = state.sketch(id)?;
     let plane = world.sketch(id).map(|w| w.plane).unwrap_or(ss.plane);
     let sk = &ss.sketch;
-    let curves: Vec<Value> = sk
+    let curves: Vec<SketchCurve> = sk
         .curves
         .iter()
         .enumerate()
         .map(|(i, c)| {
             let det = ss.report.curve_determined.get(i).copied().unwrap_or(false);
             let pid = |k: usize| sk.points.get(k).map(|p| p.id.clone()).unwrap_or_default();
-            let mut v = match c.kind {
-                CurveKind::Line { a, b } => json!({"id": c.id, "type": "line", "start": pid(a), "end": pid(b), "start_at": sk.point(a), "end_at": sk.point(b), "construction": c.construction, "fixed": sk.curve_locked(i), "fully_constrained": det}),
-                CurveKind::Circle { c: cc, r } => json!({"id": c.id, "type": "circle", "center": pid(cc), "center_at": sk.point(cc), "radius": r, "construction": c.construction, "fixed": sk.curve_locked(i), "fully_constrained": det}),
-                CurveKind::Arc { c: cc, a, b } => json!({"id": c.id, "type": "arc", "center": pid(cc), "start": pid(a), "end": pid(b), "center_at": sk.point(cc), "start_at": sk.point(a), "end_at": sk.point(b), "radius": sk.radius(i), "construction": c.construction, "fixed": sk.curve_locked(i), "fully_constrained": det}),
-                CurveKind::Ellipse { c: cc, m, r } => json!({"id": c.id, "type": "ellipse", "center": pid(cc), "major": pid(m), "center_at": sk.point(cc), "major_at": sk.point(m), "minor_radius": r, "construction": c.construction, "fixed": sk.curve_locked(i), "fully_constrained": det}),
-                CurveKind::Spline { ref pts, control, degree, periodic, ref nurbs } => {
-                    let mut v = json!({"id": c.id, "type": "spline", "points": pts.iter().map(|q| pid(*q)).collect::<Vec<_>>(), "points_at": pts.iter().map(|q| sk.point(*q)).collect::<Vec<_>>(), "control": control, "degree": degree, "periodic": periodic, "construction": c.construction, "fixed": sk.curve_locked(i), "fully_constrained": det});
-                    // A control spline with its own knots (a projected free-form edge) says them.
-                    if let (Some(n), Some(o)) = (nurbs, v.as_object_mut()) {
-                        o.insert("knots".into(), json!(n.knots));
-                        if !n.weights.is_empty() {
-                            o.insert("weights".into(), json!(n.weights));
-                        }
-                    }
-                    v
+            let at = |k: usize| sk.point(k).map(at2);
+            let shape = match c.kind {
+                CurveKind::Line { a, b } => CurveShape::Line { start: pid(a), end: pid(b), start_at: at(a), end_at: at(b) },
+                CurveKind::Circle { c: cc, r } => CurveShape::Circle { center: pid(cc), center_at: at(cc), radius: r },
+                CurveKind::Arc { c: cc, a, b } => CurveShape::Arc {
+                    center: pid(cc),
+                    start: pid(a),
+                    end: pid(b),
+                    center_at: at(cc),
+                    start_at: at(a),
+                    end_at: at(b),
+                    radius: sk.radius(i),
+                },
+                CurveKind::Ellipse { c: cc, m, r } => {
+                    CurveShape::Ellipse { center: pid(cc), major: pid(m), center_at: at(cc), major_at: at(m), minor_radius: r }
+                }
+                CurveKind::Spline { ref pts, control, degree, periodic, ref nurbs } => CurveShape::Spline {
+                    points: pts.iter().map(|q| pid(*q)).collect(),
+                    points_at: pts.iter().map(|q| at(*q)).collect(),
+                    control,
+                    degree,
+                    periodic,
+                    // A control spline with its own knots (a projected free-form edge) says them.
+                    knots: nurbs.as_ref().map(|n| n.knots.clone()),
+                    weights: nurbs.as_ref().filter(|n| !n.weights.is_empty()).map(|n| n.weights.clone()),
+                },
+                CurveKind::Conic { a, b, apex, rho } => {
+                    CurveShape::Conic { start: pid(a), end: pid(b), apex: pid(apex), start_at: at(a), end_at: at(b), apex_at: at(apex), rho }
                 }
-                CurveKind::Conic { a, b, apex, rho } => json!({"id": c.id, "type": "conic", "start": pid(a), "end": pid(b), "apex": pid(apex), "start_at": sk.point(a), "end_at": sk.point(b), "apex_at": sk.point(apex), "rho": rho, "construction": c.construction, "fixed": sk.curve_locked(i), "fully_constrained": det}),
             };
-            if let (Some(l), Some(o)) = (&c.link, v.as_object_mut()) {
-                o.insert("link".into(), json!(l));
+            SketchCurve {
+                id: c.id.clone(),
+                shape,
+                construction: c.construction,
+                fixed: sk.curve_locked(i),
+                fully_constrained: det,
+                link: c.link.clone(),
             }
-            v
         })
         .collect();
     let locked = sk.locked_points();
-    let points: Vec<Value> = sk
+    let points: Vec<SketchPoint> = sk
         .points
         .iter()
         .enumerate()
-        .map(|(i, p)| json!({"id": p.id, "at": p.pos, "world": plane.to_world(p.pos), "fixed": locked.get(i).copied().unwrap_or(false), "link": p.link, "fully_constrained": ss.report.point_determined.get(i).copied().unwrap_or(false)}))
+        .map(|(i, p)| SketchPoint {
+            id: p.id.clone(),
+            at: at2(p.pos),
+            world: plane.to_world(p.pos).into(),
+            fixed: locked.get(i).copied().unwrap_or(false),
+            link: p.link.clone(),
+            fully_constrained: ss.report.point_determined.get(i).copied().unwrap_or(false),
+        })
         .collect();
-    let constraints: Vec<Value> = sk
+    let constraints: Vec<SketchConstraint> = sk
         .constraints
         .iter()
         .map(|c| {
-            let mut v = serde_json::to_value(&c.kind).unwrap_or_default();
-            if let Some(o) = v.as_object_mut() {
-                o.insert("id".into(), json!(c.id));
-                o.insert("name".into(), json!(c.kind.name()));
-                if let Some(p) = &c.param {
-                    o.insert("param".into(), json!(p));
-                    o.insert("expression".into(), json!(s.doc.param(p).map(|x| x.expr.clone())));
-                }
+            let mut kind = match serde_json::to_value(&c.kind) {
+                Ok(Value::Object(kind)) => kind,
+                _ => Default::default(),
+            };
+            // The constraint's own keys win over any of the kind's.
+            for key in ["id", "name", "param", "expression"] {
+                kind.remove(key);
+            }
+            SketchConstraint {
+                id: c.id.clone(),
+                name: c.kind.name().to_string(),
+                param: c.param.clone(),
+                expression: c.param.as_ref().map(|p| s.doc.param(p).map(|x| x.expr.clone())),
+                kind,
             }
-            v
         })
         .collect();
-    let profiles: Vec<Value> = ss
+    let profiles: Vec<SketchProfile> = ss
         .profiles
         .iter()
         .enumerate()
         // A loop records one entry per piece it walks, and a conic or spline is walked as many
         // short pieces: each loop names a curve once, in loop order.
-        .map(|(i, p)| {
-            let holes: Vec<Vec<String>> = p.hole_curves.iter().map(|h| solidcraft_sketch::distinct_curves(h)).collect();
-            json!({"index": i, "area_mm2": p.area, "centroid_sketch": p.centroid, "curves": solidcraft_sketch::distinct_curves(&p.outer_curves), "holes": holes})
+        .map(|(i, p)| SketchProfile {
+            index: i,
+            area_mm2: p.area,
+            centroid_sketch: at2(p.centroid),
+            curves: solidcraft_sketch::distinct_curves(&p.outer_curves),
+            holes: p.hole_curves.iter().map(|h| solidcraft_sketch::distinct_curves(h)).collect(),
         })
         .collect();
-    Some(json!({
-        "id": id,
-        "name": ss.name,
-        "plane": ss.plane,
-        "status": ss.report.status,
-        "dof": ss.report.dof,
-        "fully_constrained": ss.report.fully_constrained(),
-        "failing": ss.report.failing,
-        "curves": curves,
-        "points": points,
-        "constraints": constraints,
-        "profiles": profiles,
-        "links": sk.links,
-        "wires": sk.wires.iter().map(|w| json!({"id": w.id, "points": w.pts.len(), "start": w.pts.first(), "end": w.pts.last(), "link": w.link, "arc": w.arc.map(|a| json!({"center": a.center, "radius": a.radius, "start": a.start, "end": a.end, "sweep_deg": solidcraft_sketch::arc_sweep(&a).to_degrees()}))})).collect::<Vec<_>>(),
-        "visible": crate::view::sketch_shown(s, id),
-    }))
+    let wires = sk
+        .wires
+        .iter()
+        .map(|w| SketchWire {
+            id: w.id.clone(),
+            points: w.pts.len(),
+            start: w.pts.first().map(|&p| p.into()),
+            end: w.pts.last().map(|&p| p.into()),
+            link: w.link.clone(),
+            arc: w.arc.map(|a| WireArcInfo {
+                center: a.center.into(),
+                radius: a.radius,
+                start: a.start.into(),
+                end: a.end.into(),
+                sweep_deg: solidcraft_sketch::arc_sweep(&a).to_degrees(),
+            }),
+        })
+        .collect();
+    Some(SketchInspected {
+        id,
+        name: ss.name.clone(),
+        plane: serde_json::to_value(ss.plane).unwrap_or_default(),
+        status: ss.report.status.into(),
+        dof: ss.report.dof,
+        fully_constrained: ss.report.fully_constrained(),
+        failing: ss.report.failing.clone(),
+        curves,
+        points,
+        constraints,
+        profiles,
+        links: serde_json::to_value(&sk.links).unwrap_or_default(),
+        wires,
+        visible: crate::view::sketch_shown(s, id),
+        param_warnings: Vec::new(),
+    })
 }
 
 fn sketch_inspect(s: &mut Session, p: &Value) -> Result<Value> {
     let id = super::sketch_store::target(s, p, "sketch.inspect")?;
-    sketch_json(s, &*s.world_state()?, id).ok_or_else(|| EngineError::Other("that sketch is not evaluated (rolled back or not a sketch)".into()))
+    let inspected = sketch_json(s, &*s.world_state()?, id)
+        .ok_or_else(|| EngineError::Other("that sketch is not evaluated (rolled back or not a sketch)".into()))?;
+    typed_reply("sketch.inspect", inspected)
 }
 
 /// Revisions of every design of this run (#6646).
@@ -377,24 +528,38 @@ fn revision(s: &mut Session, _p: &Value) -> Result<Value> {
 fn inspect(s: &mut Session, p: &Value) -> Result<Value> {
     let st = s.model.state();
     let (vals, perr) = s.doc.param_values();
-    let params: Vec<Value> = s
+    let params: Vec<DocumentParam> = s
         .doc
         .params
         .iter()
-        .map(|p| json!({"name": p.name, "expression": p.expr, "unit": p.unit, "value": vals.get(&p.name).map(|v| v.v), "model": p.model, "comment": p.comment, "error": perr.get(&p.name)}))
+        .map(|p| DocumentParam {
+            name: p.name.clone(),
+            expression: p.expr.clone(),
+            unit: p.unit.clone(),
+            value: vals.get(&p.name).map(|v| v.v),
+            model: p.model,
+            comment: p.comment.clone(),
+            error: perr.get(&p.name).cloned(),
+        })
         .collect();
     let marker = s.doc.marker.unwrap_or(s.doc.features.len());
-    let timeline: Vec<Value> = s
+    let timeline: Vec<TimelineEntry> = s
         .doc
         .features
         .iter()
         .enumerate()
         .map(|(i, f)| {
             let r = s.model.result(f.id);
-            json!({
-                "id": f.id, "name": f.name, "type": f.kind.type_name(), "suppressed": f.suppressed, "rolled_back": i >= marker,
-                "error": r.and_then(|r| r.error.clone()), "warning": r.and_then(|r| r.warning.clone()), "ms": r.map(|r| r.ms),
-            })
+            TimelineEntry {
+                id: f.id,
+                name: f.name.clone(),
+                kind: f.kind.type_name().to_string(),
+                suppressed: f.suppressed,
+                rolled_back: i >= marker,
+                error: r.and_then(|r| r.error.clone()),
+                warning: r.and_then(|r| r.warning.clone()),
+                ms: r.map(|r| r.ms),
+            }
         })
         .collect();
     let definitions = s.model.state();
@@ -402,46 +567,69 @@ fn inspect(s: &mut Session, p: &Value) -> Result<Value> {
     let with_counts = bool_(p, "sketch_counts").unwrap_or(false);
     // Each body is measured on its own: on all cores, in body order (as `inspect.measure`).
     let mut measured =
-        if with_measure { solidcraft_kernel::map_on_threads(&st.bodies, 16, |b| measure_sheet_json(b, Some(&definitions))) } else { Vec::new() }
+        if with_measure { solidcraft_kernel::map_on_threads(&st.bodies, 16, |b| measure_sheet(b, Some(&definitions))) } else { Vec::new() }
             .into_iter();
-    let bodies: Vec<Value> = st
+    let bodies: Vec<DocumentBody> = st
         .bodies
         .iter()
         .map(|b| {
-            let mut v = match measured.next() {
-                Some(m) => m.unwrap_or_else(|| json!({"name": b.name, "error": "measuring this body failed"})),
-                None => json!({"name": b.name, "feature": b.feature}),
-            };
-            if let Some(o) = v.as_object_mut() {
-                o.insert("visible".into(), json!(s.body_visible(&b.name)));
-                if s.body_removed_later(&b.name) {
-                    // Editing a sketch rolls the timeline back; this body is deleted further on.
-                    o.insert("removed_later".into(), json!(true));
+            let detail = match measured.next() {
+                Some(m) => {
+                    DocumentBodyDetail::Measured(Box::new(m.unwrap_or_else(|| measure_failed(b.name.clone(), "measuring this body failed".into()))))
                 }
-            }
-            v
+                None => DocumentBodyDetail::Listed { name: b.name.clone(), feature: b.feature },
+            };
+            // Editing a sketch rolls the timeline back; a body deleted further on is `removed_later`.
+            DocumentBody { detail, visible: s.body_visible(&b.name), removed_later: s.body_removed_later(&b.name).then_some(true) }
         })
         .collect();
-    let sketches: Vec<Value> = st
+    let sketches: Vec<DocumentSketch> = st
         .sketches
         .iter()
         .map(|ss| {
-            let mut v = json!({"id": ss.feature, "name": ss.name, "dof": ss.report.dof, "status": ss.report.status, "curves": ss.sketch.curves.len(), "profiles": ss.profiles.len(), "visible": crate::view::sketch_shown(s, ss.feature)});
+            let mut v = DocumentSketch {
+                id: ss.feature,
+                name: ss.name.clone(),
+                dof: ss.report.dof,
+                status: ss.report.status.into(),
+                curves: ss.sketch.curves.len(),
+                profiles: ss.profiles.len(),
+                visible: crate::view::sketch_shown(s, ss.feature),
+                plane: None,
+                points: None,
+                constraints: None,
+            };
             // A summary that stands in for the sketch's contents (the compact MCP inspect_design).
-            if with_counts && let Some(o) = v.as_object_mut() {
-                o.insert("plane".into(), json!(ss.plane));
-                o.insert("points".into(), json!(ss.sketch.points.len()));
-                o.insert("constraints".into(), json!(ss.sketch.constraints.len()));
+            if with_counts {
+                v.plane = Some(serde_json::to_value(ss.plane).unwrap_or_default());
+                v.points = Some(ss.sketch.points.len());
+                v.constraints = Some(ss.sketch.constraints.len());
             }
             v
         })
         .collect();
-    Ok(json!({
-        "name": s.doc.name, "units": s.doc.units, "metadata": s.doc.metadata, "path": s.path, "dirty": s.is_dirty(), "revision": s.revision,
-        "active_sketch": s.active_sketch, "marker": marker,
-        "params": params, "timeline": timeline, "bodies": bodies, "sketches": sketches,
-        "selection": s.selection, "undo": s.undo.len(), "redo": s.redo.len(), "hidden_origin": s.visibility.hidden_origin,
-    }))
+    typed_reply(
+        "document.inspect",
+        DocumentInspectResult {
+            name: s.doc.name.clone(),
+            units: s.doc.units.clone(),
+            metadata: s.doc.metadata.0.clone(),
+            path: s.path.clone(),
+            dirty: s.is_dirty(),
+            revision: s.revision,
+            active_sketch: s.active_sketch,
+            marker,
+            params,
+            timeline,
+            bodies,
+            sketches,
+            selection: serde_json::to_value(&s.selection).unwrap_or_default(),
+            undo: s.undo.len(),
+            redo: s.redo.len(),
+            hidden_origin: s.visibility.hidden_origin.clone(),
+            param_warnings: Vec::new(),
+        },
+    )
 }
 
 fn body_of<'a>(st: &'a solidcraft_doc::ModelState, p: &Value, cmd: &str) -> Result<&'a solidcraft_doc::ModelBody> {
@@ -530,7 +718,8 @@ fn describe(_s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn commands(s: &mut Session, _p: &Value) -> Result<Value> {
-    Ok(Value::Array(crate::command_specs().iter().map(|c| serde_json::to_value(c.info(s)).unwrap_or_default()).collect()))
+    let list: Vec<CommandEntry> = crate::command_specs().iter().map(|c| c.info(s).into()).collect();
+    typed_reply("engine.commands", list)
 }
 
 fn model_threads(s: &mut Session, _p: &Value) -> Result<Value> {
@@ -554,7 +743,7 @@ fn physical_material(s: &mut Session, p: &Value) -> Result<Value> {
             s.doc_mut().materials.insert(b.clone(), canonical.clone());
         }
     }
-    Ok(json!({"bodies": bodies, "material": canonical}))
+    typed_reply(cmd, MaterialAssignResult { bodies, material: canonical, param_warnings: Vec::new() })
 }
 
 /// A colour parameter: `"#rrggbb"` or `[r, g, b]` (0–255).
@@ -901,18 +1090,18 @@ fn appearance_list(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn material_list(s: &mut Session, _p: &Value) -> Result<Value> {
-    let built_in = solidcraft_doc::MATERIALS.iter().map(|(n, d)| json!({"name": n, "density_g_cm3": d}));
+    let built_in = solidcraft_doc::MATERIALS.iter().map(|(n, d)| ListedMaterial::BuiltIn { name: n.to_string(), density_g_cm3: *d });
     let user = s
         .doc
         .user_materials
         .iter()
         .map(|m| {
-            let mut out = super::materials::material_json(m)?;
-            out["appearance"] = json!(s.doc.material_look(&m.name).as_ref().map(look_json));
-            Ok(out)
+            let mut out = super::materials::listed_material(m)?;
+            out.appearance = s.doc.material_look(&m.name).as_ref().map(LookReply::from);
+            Ok(ListedMaterial::Design(Box::new(out)))
         })
         .collect::<Result<Vec<_>>>()?;
-    Ok(json!({"materials": built_in.chain(user).collect::<Vec<_>>()}))
+    typed_reply("material.list", MaterialListResult { materials: built_in.chain(user).collect(), param_warnings: Vec::new() })
 }
 
 fn colored_components(s: &mut Session, p: &Value) -> Result<Value> {

crates/engine/src/cmd/interference.rs

@@ -13,7 +13,7 @@
 use std::collections::HashSet;
 use std::sync::Arc;
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcore_record::Vec3;
 use solidcraft_geom::mesh_distance::TriangleSet;
 use solidcraft_geom::{Aabb3, Mesh};
@@ -21,6 +21,8 @@ use solidcraft_kernel::Body;
 use solidcraft_kernel::profile::KernelTimes;
 
 use crate::params::{bad, num, string_list};
+use crate::schema::clearance::{Overlap, OverlapBounds, Unchecked};
+use crate::schema::interference::{InterferenceResult, PairTime};
 use crate::{Result, Session};
 
 /// Most pairs with overlapping bounding boxes one call intersects.
@@ -49,7 +51,7 @@ struct Job {
 
 /// What an exact check of one pair came to.
 enum Outcome {
-    Hit(Value),
+    Hit(Overlap),
     Clear,
     Unchecked(String),
 }
@@ -159,26 +161,30 @@ pub(super) fn interference(s: &mut Session, p: &Value) -> Result<Value> {
     let waited_ms = waited.elapsed().as_secs_f64() * 1000.0;
 
     // Mesh bodies are not intersected: say so, rather than let `count: 0` read as "no overlap".
-    let mut unchecked: Vec<Value> = meshes_left.iter().map(|b| json!({"a": b.name, "b": null, "reason": MESH_NOT_CHECKED})).collect();
+    let mut unchecked: Vec<Unchecked> =
+        meshes_left.iter().map(|b| Unchecked { a: b.name.clone(), b: None, reason: MESH_NOT_CHECKED.to_string() }).collect();
     let (mut hits, mut timed) = (Vec::new(), Vec::new());
     let (mut not_checked, mut boolean_ms, mut tessellate_ms) = (0usize, 0.0, 0.0);
     for ((a, b), d) in done {
         let Some(d) = d else {
             not_checked += 1;
-            unchecked.push(json!({"a": a, "b": b, "reason": format!("not checked: the time budget of {budget_s} s ran out (budget_s)")}));
+            unchecked.push(Unchecked { a, b: Some(b), reason: format!("not checked: the time budget of {budget_s} s ran out (budget_s)") });
             continue;
         };
         boolean_ms += d.kernel.boolean_ms;
         tessellate_ms += d.kernel.tessellate_ms;
-        timed.push((
-            d.ms,
-            json!({"a": a, "b": b, "ms": round_ms(d.ms), "boolean_ms": round_ms(d.kernel.boolean_ms),
-            "tessellate_ms": round_ms(d.kernel.tessellate_ms)}),
-        ));
+        let time = PairTime {
+            a: a.clone(),
+            b: b.clone(),
+            ms: round_ms(d.ms),
+            boolean_ms: round_ms(d.kernel.boolean_ms),
+            tessellate_ms: round_ms(d.kernel.tessellate_ms),
+        };
+        timed.push((d.ms, time));
         match d.outcome {
-            Outcome::Hit(v) => hits.push(v),
+            Outcome::Hit(overlap) => hits.push(overlap),
             Outcome::Clear => {}
-            Outcome::Unchecked(reason) => unchecked.push(json!({"a": a, "b": b, "reason": reason})),
+            Outcome::Unchecked(reason) => unchecked.push(Unchecked { a, b: Some(b), reason }),
         }
     }
     // A timing profile of the command (`--profile`) counts the kernel time the workers spent,
@@ -189,15 +195,28 @@ pub(super) fn interference(s: &mut Session, p: &Value) -> Result<Value> {
         solidcraft_kernel::profile::credit(KernelTimes { boolean_ms: boolean_ms * share, tessellate_ms: tessellate_ms * share });
     }
     timed.sort_by(|x, y| y.0.total_cmp(&x.0));
-    let slowest: Vec<Value> = timed.into_iter().take(SLOWEST).map(|t| t.1).collect();
-    Ok(json!({
-        "interferences": hits, "count": hits.len(), "checked": bodies.len(), "unchecked": unchecked,
-        "truncated": skipped > 0, "skipped_pairs": skipped,
-        "pairs_candidate": pairs.len(), "pairs_cleared": cleared, "pairs_intersected": intersected,
-        "pairs_not_checked": not_checked, "budget_s": budget_s, "budget_exceeded": not_checked > 0,
-        "threads": threads, "boolean_ms": round_ms(boolean_ms), "tessellate_ms": round_ms(tessellate_ms),
-        "slowest": slowest, "ms": round_ms(started.elapsed().as_secs_f64() * 1000.0),
-    }))
+    let slowest: Vec<PairTime> = timed.into_iter().take(SLOWEST).map(|t| t.1).collect();
+    let reply = InterferenceResult {
+        count: hits.len(),
+        interferences: hits,
+        checked: bodies.len(),
+        unchecked,
+        truncated: skipped > 0,
+        skipped_pairs: skipped,
+        pairs_candidate: pairs.len(),
+        pairs_cleared: cleared,
+        pairs_intersected: intersected,
+        pairs_not_checked: not_checked,
+        budget_s,
+        budget_exceeded: not_checked > 0,
+        threads,
+        boolean_ms: round_ms(boolean_ms),
+        tessellate_ms: round_ms(tessellate_ms),
+        slowest,
+        ms: round_ms(started.elapsed().as_secs_f64() * 1000.0),
+        param_warnings: Vec::new(),
+    };
+    serde_json::to_value(reply).map_err(|e| crate::EngineError::Other(e.to_string()))
 }
 
 fn round_ms(ms: f64) -> f64 {
@@ -284,9 +303,14 @@ fn check_pair(a: &Body, b: &Body, (na, nb): &(String, String)) -> Outcome {
         Err(e) => return Outcome::Unchecked(e.to_string()),
     };
     if m.volume > threshold {
-        let hit = json!({"a": na, "b": nb, "volume_mm3": m.volume, "area_mm2": m.area, "center": m.centroid,
-            "bbox": {"min": m.bbox.min, "max": m.bbox.max}});
-        return Outcome::Hit(hit);
+        return Outcome::Hit(Overlap {
+            a: na.clone(),
+            b: nb.clone(),
+            volume_mm3: m.volume,
+            area_mm2: m.area,
+            bbox: OverlapBounds { min: m.bbox.min.into(), max: m.bbox.max.into() },
+            center: m.centroid.into(),
+        });
     }
     Outcome::Clear
 }

crates/engine/src/cmd/joints.rs

@@ -15,20 +15,54 @@ use solidcraft_geom::Aabb3;
 
 use super::CommandSpec;
 use crate::params::{bad, bool_, num, str_, vec3};
-use crate::schema::joints::EditJointResult;
+use crate::schema::joints::{
+    AsBuiltJointParams, CamLift, CamParams, CamResult, ContactStop, CouplingResult, CreateJointParams, DeleteJointParams, DeleteJointResult,
+    DriveJointParams, DriveJointResult, EditJointResult, FloatingChain, GearParams, HeldValue, InspectJointParams, InspectJointResult,
+    JointAddedResult, JointDeleted, JointFrame, JointLimitsParams, JointProblem, LimitSide, LimitStop, LinkInfo, ListJointsParams, ListJointsResult,
+    ListedJoint, ListedOrigin, LoopStop, MakeJointOriginParams, MakeJointOriginResult, MotionLinkParams, NamedValue, OccurrenceDof, RackPinionParams,
+    ReachLoopStop, ReachParams, ReachResult, ReachedJoint, RigidGroupParams, RigidGroupResult, ScrewParams, SolveJointsParams, SolveReport,
+    SolveResult, ValueUnit,
+};
 use crate::schema::{TypedContract, output_schema_for};
 use crate::{EngineError, Result, Session};
 
 const EDIT_CONTRACT: TypedContract<crate::schema::joints::EditJointParams> = TypedContract::new();
+const CREATE_CONTRACT: TypedContract<CreateJointParams> = TypedContract::new();
+const AS_BUILT_CONTRACT: TypedContract<AsBuiltJointParams> = TypedContract::new();
+const DRIVE_CONTRACT: TypedContract<DriveJointParams> = TypedContract::new();
+const LIMITS_CONTRACT: TypedContract<JointLimitsParams> = TypedContract::new();
+const DELETE_CONTRACT: TypedContract<DeleteJointParams> = TypedContract::new();
+const LIST_CONTRACT: TypedContract<ListJointsParams> = TypedContract::new();
+const INSPECT_CONTRACT: TypedContract<InspectJointParams> = TypedContract::new();
+const SOLVE_CONTRACT: TypedContract<SolveJointsParams> = TypedContract::new();
+const ORIGIN_CONTRACT: TypedContract<MakeJointOriginParams> = TypedContract::new();
+const RIGID_GROUP_CONTRACT: TypedContract<RigidGroupParams> = TypedContract::new();
+const REACH_CONTRACT: TypedContract<ReachParams> = TypedContract::new();
+const MOTION_LINK_CONTRACT: TypedContract<MotionLinkParams> = TypedContract::new();
+const GEAR_CONTRACT: TypedContract<GearParams> = TypedContract::new();
+const RACK_PINION_CONTRACT: TypedContract<RackPinionParams> = TypedContract::new();
+const SCREW_CONTRACT: TypedContract<ScrewParams> = TypedContract::new();
+const CAM_CONTRACT: TypedContract<CamParams> = TypedContract::new();
 
 #[path = "joints_inspect.rs"]
 mod inspect;
 
 pub static COMMANDS: &[CommandSpec] = &[
-    CommandSpec::new("joint.origin", "Joint Origin", joint_origin).at("SOLID", "CREATE").icon("joint_origin").params(
+    CommandSpec::new("joint.origin", "Joint Origin", crate::checked!("joint.origin", joint_origin))
+        .at("SOLID", "CREATE")
+        .icon("joint_origin")
+        .contract(&ORIGIN_CONTRACT)
+        .output(output_schema_for::<MakeJointOriginResult>)
+        .params(
         "name?, occurrence?: id|name (default: from the pick, or the named face's component), face: [x,y,z] | \"<name>\" (centre of a planar face) | circle: [x,y,z] | \"<name>\" (centre of a round end: a point on its wall or rim, the end's centre, or the round face's name as model.faces lists it) | edge: [x,y,z] (a point on an edge of a planar face: the edge's middle, z out of the face, y into it; on?: [x,y,z] a point on the face (default: the larger planar face beside the edge); corner?: [x,y,z] near one end: the corner there, x and y along its two edges into the face; found again by name, so it follows the face as it changes size; z?: [x,y,z] the frame's z instead of the face's normal, along the edge when it runs that way, x chosen from z: an edge or corner picked as it is, kept as a point where it can't be found by name) | point: [x,y,z], z?: [x,y,z]; a circle's z?: [x,y,z] (a round edge's centre with the way out of it: its end by name when that is the frame it shows, else a point there); body?: the named face's body; end?: \"<name>\" (a circle's end: the face across its rim there; default the end nearer the pick); x?: [x,y,z] (a direction, world) | \"<face name>\" | {face: [x,y,z]} (the frame's x: a direction, a plane's normal, or the way to another hole's axis; keeps a round origin's turn; a point's x is a direction, laid square to its z, default: chosen from z alone). Faces are kept by name: the origin follows its face, and a circle its end, when the design changes",
     ),
-    CommandSpec::new("joint.create", "Joint", joint).at("SOLID", "ASSEMBLE").icon("joint").key("J").params(
+    CommandSpec::new("joint.create", "Joint", crate::checked!("joint.create", joint))
+        .at("SOLID", "ASSEMBLE")
+        .icon("joint")
+        .key("J")
+        .contract(&CREATE_CONTRACT)
+        .output(output_schema_for::<JointAddedResult>)
+        .params(
         "type: rigid|revolute|slider|cylindrical|pin_slot|planar|ball, or a relation: parallel|perpendicular|angle|point_on_plane|point_on_line|line_on_plane \
          (ties only some directions or points, made where the parts are; several between two parts add up); a, b: joint origins ({occurrence, face|circle|edge|point: [x,y,z] in world, or face|circle: \"<face name>\"; z? for a point, end?, x? as joint.origin} | origin name); \
          values?: [angles in deg or expressions, distances]; limits?: [[min, max] | null…]; flip?: bool (default false: the origins are mated, \
@@ -40,12 +74,27 @@ pub static COMMANDS: &[CommandSpec] = &[
          kept with the joint and worked out again whenever the design changes, so the joint follows the parameters it names; a joint whose \
          expression no longer works out (a parameter deleted) is left out of the solve with the reason in its errors",
     ),
-    CommandSpec::new("joint.as_built", "As-Built Joint", as_built).at("SOLID", "ASSEMBLE").icon("as_built").params(
+    CommandSpec::new("joint.as_built", "As-Built Joint", crate::checked!("joint.as_built", as_built))
+        .at("SOLID", "ASSEMBLE")
+        .icon("as_built")
+        .contract(&AS_BUILT_CONTRACT)
+        .output(output_schema_for::<JointAddedResult>)
+        .params(
         "type, a: occurrence, b: occurrence (stay where they are); at?: joint origin (default: b's origin) — the joint's frame; one on a or b is kept on its face or hole there, so the joint follows it as the design changes; \
          name?; limits?: [[min, max] | null…]; quiet?: bool",
     ),
-    CommandSpec::new("joint.rigid_group", "Rigid Group", rigid_group).at("SOLID", "ASSEMBLE").icon("rigid_group").params("occurrences: [ids or names] (move together, as they are)"),
-    CommandSpec::new("joint.drive", "Drive Joints", drive).at("SOLID", "ASSEMBLE").icon("drive").params(
+    CommandSpec::new("joint.rigid_group", "Rigid Group", crate::checked!("joint.rigid_group", rigid_group))
+        .at("SOLID", "ASSEMBLE")
+        .icon("rigid_group")
+        .contract(&RIGID_GROUP_CONTRACT)
+        .output(output_schema_for::<RigidGroupResult>)
+        .params("occurrences: [ids or names] (move together, as they are)"),
+    CommandSpec::new("joint.drive", "Drive Joints", crate::checked!("joint.drive", drive))
+        .at("SOLID", "ASSEMBLE")
+        .icon("drive")
+        .contract(&DRIVE_CONTRACT)
+        .output(output_schema_for::<DriveJointResult>)
+        .params(
         "joint: id|name; value | values: [angles in deg or expressions, distances] (values not given keep theirs; a value driven drops the expression joint.create gave it; clamped to the limits; the other joints of a \
          closed loop follow, and the motion stops where the loop can no longer close → stopped_by_loop); quiet?: bool (leave out dof \
          and fixed) → values: [{name, value, unit: deg|mm, limits}] as joint.list gives them; requested: the values asked for, in the same form; \
@@ -54,36 +103,66 @@ pub static COMMANDS: &[CommandSpec] = &[
          reason: why the joint can move nothing (suppressed: nothing is stored; its origins lost; its chain joined to nothing grounded → unconnected: \
          the occurrence named; or, when nothing moved, the first held value's why); index?: zero-based coordinate to drive with value (the other coordinates follow); continuous?: bool (drag frame, suppress UI echo)",
     ),
-    CommandSpec::new("joint.reach", "Reach Point", reach).icon("reach").params(
+    CommandSpec::new("joint.reach", "Reach Point", crate::checked!("joint.reach", reach))
+        .icon("reach")
+        .contract(&REACH_CONTRACT)
+        .output(output_schema_for::<ReachResult>)
+        .params(
         "occurrence: id|name; point: [x,y,z] (where its point goes, world); at?: [x,y,z] (its point, in the world where it is now; default: the centre of          its bodies' box); z?: [x,y,z] (the way its axis then points); axis?: [x,y,z] (that axis, in the world now; default: its own z); joints?: [ids          or names] (only these move toward the point; the other joints of a closed loop they are in follow); quiet?: bool; continuous?: bool (a frame          of a drag: the answer says continuous, and the app's command line doesn't echo it). Moves the values of the joints          on its chain from where they are to the nearest pose, within their limits, through motion links, keeping closed loops closed as joint.drive does          (contact sets are not checked) → reached; error_mm (and error_deg with z): how close it got; point: where its point is; values: [{joint, name,          values}] of the joints that moved, as joint.list gives them; moved; stopped_by_limit: [{joint, value, limit: min|max}]: the limits it rests on          short of the point; stopped_by_loop: {joint}: the closed loop that stopped it (its chain alone gets closer); reason: why nothing can move",
     ),
-    CommandSpec::new("joint.motion_link", "Motion Link", motion_link)
+    CommandSpec::new("joint.motion_link", "Motion Link", crate::checked!("joint.motion_link", motion_link))
         .at("SOLID", "ASSEMBLE")
         .icon("motion_link")
+        .contract(&MOTION_LINK_CONTRACT)
+        .output(output_schema_for::<SolveResult>)
         .params("a, b: joints; ratio (b = ratio · a + offset): b's units per a's (mm per deg for an angle driving a distance); offset?: in b's units (deg for an angle, mm for a distance, or an expression); ia?, ib?: value indices (default 0)"),
-    CommandSpec::new("joint.gear", "Gear", gear).at("SOLID", "ASSEMBLE").icon("gear").params(
+    CommandSpec::new("joint.gear", "Gear", crate::checked!("joint.gear", gear))
+        .at("SOLID", "ASSEMBLE")
+        .icon("gear")
+        .contract(&GEAR_CONTRACT)
+        .output(output_schema_for::<CouplingResult>)
+        .params(
         "a, b: joints that turn (revolute), b driven by a; ra, rb: the gears' pitch radii (or tooth counts): mm, an expression, or \
          {circle: [x,y,z], occurrence?}: the round face there, its radius (read again whenever the design changes, so the ratio follows \
          edits); internal?: bool (one is a ring gear: both turn the same way; by default b turns the other way); reverse?: bool; \
          link?: index (replace that motion link) → link, ratio (b's degrees per a's); b keeps where it is, also when the link replaces \
          another (at the current pose)",
     ),
-    CommandSpec::new("joint.rack_pinion", "Rack and Pinion", rack_pinion).at("SOLID", "ASSEMBLE").icon("rack_pinion").params(
+    CommandSpec::new("joint.rack_pinion", "Rack and Pinion", crate::checked!("joint.rack_pinion", rack_pinion))
+        .at("SOLID", "ASSEMBLE")
+        .icon("rack_pinion")
+        .contract(&RACK_PINION_CONTRACT)
+        .output(output_schema_for::<CouplingResult>)
+        .params(
         "a, b: a joint that turns (revolute: the pinion) and one that slides (slider: the rack), in either order, b driven by a; \
          radius: the pinion's pitch radius (mm, an expression, or {circle: [x,y,z], occurrence?}): the rack travels radius × the turn in \
          radians; reverse?: bool; link?: index (replace that motion link) → link, ratio (mm per degree, or degrees per mm); b keeps \
          where it is, also when the link replaces another (at the current pose)",
     ),
-    CommandSpec::new("joint.screw", "Screw", screw).at("SOLID", "ASSEMBLE").icon("screw").params(
+    CommandSpec::new("joint.screw", "Screw", crate::checked!("joint.screw", screw))
+        .at("SOLID", "ASSEMBLE")
+        .icon("screw")
+        .contract(&SCREW_CONTRACT)
+        .output(output_schema_for::<CouplingResult>)
+        .params(
         "joint: a cylindrical joint (its turn drives its travel) | a, b: a joint that turns and one that slides, b driven by a; pitch: \
          travel per turn (mm or an expression); reverse?: bool (a left-hand thread); link?: index (replace that motion link) → link, \
          ratio (mm per degree, or degrees per mm); b keeps where it is, also when the link replaces another (at the current \
          pose)",
     ),
-    CommandSpec::new("joint.cam", "Cam", cam_cmd).at("SOLID", "ASSEMBLE").icon("cam").params(
+    CommandSpec::new("joint.cam", "Cam", crate::checked!("joint.cam", cam_cmd))
+        .at("SOLID", "ASSEMBLE")
+        .icon("cam")
+        .contract(&CAM_CONTRACT)
+        .output(output_schema_for::<CamResult>)
+        .params(
         "a: the cam's joint (revolute); b: the follower's joint, a slider (a translating follower) or a revolute (an oscillating one),          b driven by a; profile: {sketch: id|name, index?: the profile (default: the largest)} | {edges: [[x,y,z]…] (points on edges of          the cam's bodies forming one closed loop, world), occurrence?}: the cam's outline, in a plane square to its axis, read again          whenever the design changes; follower?: knife|roller|flat (default knife; flat: a face square to a slider's line); radius?: the          roller's radius (mm, an expression or {circle: [x,y,z], occurrence?}: the roller's round face, which is its tip too); tip?: a          joint origin where the follower touches: its knife's point or its roller's centre, such as {circle: [x,y,z]} on the roller          (needed for an oscillating follower; a translating one's line runs through it, by default along its slider's axis); flip?: bool (ride the cam from the other side          than the one the follower is on now); link?: index (replace that motion link) → link, lift: {min, max, rise, unit} (b's travel          over a turn of the cam), reverse (the side it rides from), follower_offset (mm: how far a translating follower's line passes          from the cam's axis); b keeps where it is, also when the link replaces another (at the current pose)",
     ),
-    CommandSpec::new("joint.limits", "Joint Limits", limits).icon("joint").params("joint; index?: value index (default 0); min?, max? (omit both to clear)"),
+    CommandSpec::new("joint.limits", "Joint Limits", crate::checked!("joint.limits", limits))
+        .icon("joint")
+        .contract(&LIMITS_CONTRACT)
+        .output(output_schema_for::<SolveResult>)
+        .params("joint; index?: value index (default 0); min?, max? (omit both to clear)"),
     CommandSpec::new("joint.edit", "Edit Joint", crate::checked!("joint.edit", edit))
         .icon("edit")
         .contract(&EDIT_CONTRACT)
@@ -94,12 +173,26 @@ pub static COMMANDS: &[CommandSpec] = &[
              its limits and expressions (a relation's values start again where its parts are); an edit that places it again (not a rename alone) \
              meets a loop it closes as joint.create does, turning an angle a half turn where only that meets it",
         ),
-    CommandSpec::new("joint.delete", "Delete Joint", delete).icon("delete").params("joint: id|name (or origin: name, link: index)"),
-    CommandSpec::new("joint.list", "List Joints", list).icon("list").noundo().params(
+    CommandSpec::new("joint.delete", "Delete Joint", crate::checked!("joint.delete", delete))
+        .icon("delete")
+        .contract(&DELETE_CONTRACT)
+        .output(output_schema_for::<DeleteJointResult>)
+        .params("joint: id|name (or origin: name, link: index)"),
+    CommandSpec::new("joint.list", "List Joints", crate::checked!("joint.list", list))
+        .icon("list")
+        .noundo()
+        .contract(&LIST_CONTRACT)
+        .output(output_schema_for::<ListJointsResult>)
+        .params(
         "→ joints (type, occurrences, values, limits; expressions: {offset?, angle?, values?} when they were typed as expressions), origins, links, degrees of freedom, conflicts, floating: [{occurrences, joints}] \
          (joint chains joined to nothing grounded: the solver places none of them, so driving them moves nothing)",
     ),
-    CommandSpec::new("joint.inspect", "Inspect Joint", inspect::inspect).icon("inspect").noundo().params(
+    CommandSpec::new("joint.inspect", "Inspect Joint", crate::checked!("joint.inspect", inspect::inspect))
+        .icon("inspect")
+        .noundo()
+        .contract(&INSPECT_CONTRACT)
+        .output(output_schema_for::<InspectJointResult>)
+        .params(
         "joint?: id|name (default: every joint) → joints: [{id, name, type, suppressed, visible, flip, offset (mm), angle (deg), values: as joint.list \
          gives them, dofs, expressions?: {offset?, angle?, values?}, a, b: {occurrence, occurrence_name, component, component_name, path \
          (occurrence names from the top, `/` between), snap (as saved: type, pick, face, end, edge, corner, x, point, z, in the component's \
@@ -108,8 +201,18 @@ pub static COMMANDS: &[CommandSpec] = &[
          unverified?: a name saved before exact names}], resolves, frame?: {origin, z, x} in the world, error?: why the origin is lost}, \
          links: [{index, role: driver|driven, …as joint.list}], errors, conflicts}] (reads only: nothing changes)",
     ),
-    CommandSpec::new("joint.solve", "Solve Joints", solve_cmd).icon("compute").params("re-place the occurrences from the joints → conflicts, errors, dof"),
-    CommandSpec::new("inspect.interference", "Interference", super::interference::interference).at("SOLID", "INSPECT").icon("interference").noundo().params(
+    CommandSpec::new("joint.solve", "Solve Joints", crate::checked!("joint.solve", solve_cmd))
+        .icon("compute")
+        .contract(&SOLVE_CONTRACT)
+        .output(output_schema_for::<SolveResult>)
+        .params("re-place the occurrences from the joints → conflicts, errors, dof"),
+    CommandSpec::new("inspect.interference", "Interference", crate::checked!("inspect.interference", super::interference::interference))
+        .contract(&crate::schema::TypedContract::<crate::schema::interference::InterferenceParams>::new())
+        .output(crate::schema::output_schema_for::<crate::schema::interference::InterferenceResult>)
+        .at("SOLID", "INSPECT")
+        .icon("interference")
+        .noundo()
+        .params(
         "bodies?: [names] (default: all, in world placement; a name that is no body is refused); budget_s?: seconds (default 240, at most 86400: pairs not finished by then are listed in unchecked as \"not checked: the time budget … ran out\" and the call returns) → interferences: pairs that overlap with the overlap volume, area, bounding box and centre; unchecked: [{a, b, reason}], the pairs that could not be checked, with the reason, and each mesh body (STL, 3MF or OBJ import: not intersected) as {a: name, b: null, reason: \"mesh body: not checked\"}, so count: 0 is not read as no overlap (checked counts the solid bodies). Bodies are pruned by bounding box first, then by their display meshes (pairs whose meshes stay apart by more than their chord tolerances, neither inside the other, are clear without a boolean), so any number of bodies is fine; the pairs left are intersected exactly, in parallel on desktop, the slowest first; at most 20000 pairs whose boxes overlap are intersected per call (truncated: true and skipped_pairs: n say when more were left out). Also: pairs_candidate (boxes overlap), pairs_cleared (by the meshes), pairs_intersected, pairs_not_checked, budget_exceeded, threads (worker threads; 0: on the calling thread), boolean_ms and tessellate_ms (kernel time summed over the pairs), slowest: [{a, b, ms, boolean_ms, tessellate_ms}] and ms",
     ),
 ];
@@ -222,30 +325,52 @@ fn response_analysis(p: &Value) -> joints::Analysis {
 }
 
 /// A solve's answer; `quiet: true` in the command's params leaves out the per-occurrence lists.
-fn sol_json(sol: &joints::Solution, p: &Value) -> Value {
-    let mut out = json!({
-        "conflicts": sol.conflicts.iter().map(|(id, n, w)| json!({"joint": id, "name": n, "why": w})).collect::<Vec<_>>(),
-        "errors": sol.errors.iter().map(|(id, n, w)| json!({"joint": id, "name": n, "why": w})).collect::<Vec<_>>(),
-    });
-    if !bool_(p, "quiet").unwrap_or(false) {
-        out["dof"] = sol.dof.iter().map(|(o, d)| json!({"occurrence": o, "dof": d})).collect();
-        out["fixed"] = json!(sol.fixed);
+fn solve_report(sol: &joints::Solution, p: &Value) -> SolveReport {
+    let problems = |list: &[(u64, String, String)]| -> Vec<JointProblem> {
+        list.iter().map(|(joint, name, why)| JointProblem { joint: *joint, name: name.clone(), why: why.clone() }).collect()
+    };
+    let quiet = bool_(p, "quiet").unwrap_or(false);
+    SolveReport {
+        conflicts: problems(&sol.conflicts),
+        errors: problems(&sol.errors),
+        dof: (!quiet).then(|| sol.dof.iter().map(|(o, d)| OccurrenceDof { occurrence: *o, dof: *d }).collect()),
+        fixed: (!quiet).then(|| sol.fixed.clone()),
     }
-    out
+}
+
+/// [`solve_report`] as JSON, for the commands that add to it.
+fn sol_json(sol: &joints::Solution, p: &Value) -> Value {
+    serde_json::to_value(solve_report(sol, p)).unwrap_or_default()
+}
+
+/// A command's reply as JSON: the joint commands that have output schemas build their replies from
+/// the types those describe, so the two can't drift apart.
+fn reply(cmd: &str, reply: impl serde::Serialize) -> Result<Value> {
+    serde_json::to_value(reply).map_err(|e| bad(cmd, e.to_string()))
 }
 
 /// A joint's values as `joint.list` gives them: degrees for angles, mm for distances, each with
 /// its name and limits. The numbers are rounded for reading (#10747); the joint keeps full
 /// precision.
-pub(crate) fn named_values(j: &Joint, q: &[f64]) -> Vec<Value> {
+pub(crate) fn named_value_list(j: &Joint, q: &[f64]) -> Vec<NamedValue> {
     j.kind
         .dofs()
         .iter()
         .enumerate()
         .map(|(i, n)| {
             let (v, angle) = (q.get(i).copied().unwrap_or(0.0), j.kind.is_angle(i));
-            json!({"name": n, "value": expr::round_reported(if angle { v.to_degrees() } else { v }), "unit": if angle { "deg" } else { "mm" },
-                "limits": j.limits.get(i).copied().flatten().map(|(a, b)| if angle { [expr::round_reported(a.to_degrees()), expr::round_reported(b.to_degrees())] } else { [expr::round_reported(a), expr::round_reported(b)] })})
+            NamedValue {
+                name: (*n).to_string(),
+                value: expr::round_reported(if angle { v.to_degrees() } else { v }),
+                unit: if angle { ValueUnit::Deg } else { ValueUnit::Mm },
+                limits: j.limits.get(i).copied().flatten().map(|(a, b)| {
+                    if angle {
+                        [expr::round_reported(a.to_degrees()), expr::round_reported(b.to_degrees())]
+                    } else {
+                        [expr::round_reported(a), expr::round_reported(b)]
+                    }
+                }),
+            }
         })
         .collect()
 }
@@ -253,9 +378,14 @@ pub(crate) fn named_values(j: &Joint, q: &[f64]) -> Vec<Value> {
 /// A joint's values as the solver places it (after motion links, so a screw's travel follows its
 /// turn), named as `joint.list` gives them.
 pub(crate) fn effective_values(s: &Session, id: u64) -> Option<Vec<Value>> {
+    effective_value_list(s, id).map(|list| list.into_iter().map(|v| serde_json::to_value(v).unwrap_or_default()).collect())
+}
+
+/// [`effective_values`], typed.
+fn effective_value_list(s: &Session, id: u64) -> Option<Vec<NamedValue>> {
     let j = s.doc.assembly.joints.iter().find(|j| j.id == id)?;
     let vals = joints::joint_values(&s.doc.assembly);
-    Some(named_values(j, vals.get(&id).map(Vec::as_slice).unwrap_or(&j.values)))
+    Some(named_value_list(j, vals.get(&id).map(Vec::as_slice).unwrap_or(&j.values)))
 }
 
 fn occurrence_name(s: &Session, id: u64) -> String {
@@ -287,7 +417,7 @@ pub(crate) fn cannot_move(s: &Session, sol: &joints::Solution, id: u64) -> Optio
 
 /// Joint chains joined to nothing grounded, which the solver places none of: each chain's
 /// occurrences and joints, by name.
-fn floating_chains(s: &Session, sol: &joints::Solution) -> Vec<Value> {
+fn floating_chains(s: &Session, sol: &joints::Solution) -> Vec<FloatingChain> {
     let placed = |o: u64| o == 0 || sol.world.contains_key(&o);
     let errors: BTreeSet<u64> = sol.errors.iter().map(|e| e.0).collect();
     let mut next: BTreeMap<u64, Vec<(u64, &Joint)>> = BTreeMap::new();
@@ -313,8 +443,10 @@ fn floating_chains(s: &Session, sol: &joints::Solution) -> Vec<Value> {
                 }
             }
         }
-        out.push(json!({"occurrences": occs.iter().map(|o| occurrence_name(s, *o)).collect::<Vec<_>>(),
-            "joints": js.iter().map(|(_, n)| *n).collect::<Vec<_>>()}));
+        out.push(FloatingChain {
+            occurrences: occs.iter().map(|o| occurrence_name(s, *o)).collect(),
+            joints: js.iter().map(|(_, n)| (*n).to_string()).collect(),
+        });
     }
     out
 }
@@ -495,7 +627,7 @@ fn same_frame(s: &Session, o: &JointOrigin, at: Vec3, z: Vec3) -> bool {
 /// The longest face name a joint origin takes. A face that cuts split and merged keeps the names
 /// of the faces around it (`<name>#[<name>,…]`): several hundred characters on a part a text or
 /// a pattern of holes was cut through.
-const MAX_FACE_NAME: usize = 16_384;
+pub(crate) const MAX_FACE_NAME: usize = 16_384;
 
 /// The component an occurrence places (0 for the root, or an unknown occurrence).
 pub(crate) fn component_of(s: &Session, occurrence: u64) -> u64 {
@@ -748,21 +880,27 @@ fn add_joint(s: &mut Session, mut j: Joint, p: &Value) -> Result<Value> {
     let mut q = j.values.clone();
     q.resize(j.kind.dofs().len(), 0.0);
     joints::clamp(&j, &mut q);
-    let round = |v: &Value| v.as_f64().map(|x| (x * 1e6).round() / 1e6).unwrap_or(f64::NAN);
-    let warnings: Vec<String> = named_values(&j, &q)
+    let round = |v: f64| (v * 1e6).round() / 1e6;
+    // As the reply shows them: a value that is not a number reads as null, and null is null.
+    let same = |a: f64, b: f64| a == b || (a.is_nan() && b.is_nan());
+    let warnings: Vec<String> = named_value_list(&j, &q)
         .iter()
-        .zip(named_values(&j, &j.values))
-        .filter(|(now, was)| now["value"] != was["value"])
+        .zip(named_value_list(&j, &j.values))
+        .filter(|(now, was)| !same(now.value, was.value))
         .map(|(now, was)| {
-            let unit = now["unit"].as_str().unwrap_or("");
+            let unit = match now.unit {
+                ValueUnit::Deg => "deg",
+                ValueUnit::Mm => "mm",
+            };
+            let [lo, hi] = now.limits.unwrap_or([f64::NAN; 2]);
             format!(
                 "{} {} starts at {} {unit}, inside its limits [{}, {}], not at {} {unit}: the part moved there as it was joined",
                 j.name,
-                now["name"].as_str().unwrap_or(""),
-                round(&now["value"]),
-                round(&now["limits"][0]),
-                round(&now["limits"][1]),
-                round(&was["value"])
+                now.name,
+                round(now.value),
+                round(lo),
+                round(hi),
+                round(was.value)
             )
         })
         .collect();
@@ -776,13 +914,7 @@ fn add_joint(s: &mut Session, mut j: Joint, p: &Value) -> Result<Value> {
     if sol.conflicts.iter().any(|(c, ..)| *c == id) && close_by_half_turn(s, id, &sol) {
         sol = resolve(s);
     }
-    let mut out = sol_json(&sol, p);
-    out["joint"] = json!(id);
-    out["name"] = json!(name);
-    if !warnings.is_empty() {
-        out["warnings"] = json!(warnings);
-    }
-    Ok(out)
+    reply("joint.create", JointAddedResult { solved: solve_report(&sol, p), joint: id, name, warnings, param_warnings: Vec::new() })
 }
 
 /// Sets of angle values a new loop-closing joint tries a half turn round, at most.
@@ -886,7 +1018,7 @@ fn joint_origin(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad(cmd, format!("there is already a joint origin `{name}`")));
     }
     s.doc_mut().assembly.origins.push(NamedOrigin { name: name.clone(), origin });
-    Ok(json!({"origin": name}))
+    reply(cmd, MakeJointOriginResult { origin: name, param_warnings: Vec::new() })
 }
 
 fn kind_param(p: &Value, cmd: &str) -> Result<JointKind> {
@@ -1007,9 +1139,9 @@ fn rigid_group(s: &mut Session, p: &Value) -> Result<Value> {
     let mut made = Vec::new();
     for other in ids.iter().skip(1) {
         let r = as_built(s, &json!({"type": "rigid", "a": first, "b": other, "name": format!("Rigid Group {first}:{other}")}))?;
-        made.push(r["joint"].clone());
+        made.push(r["joint"].as_u64().ok_or_else(|| bad(cmd, "the joint made has no id"))?);
     }
-    Ok(json!({"joints": made}))
+    reply(cmd, RigidGroupResult { joints: made, param_warnings: Vec::new() })
 }
 
 fn drive(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1081,41 +1213,48 @@ fn drive(s: &mut Session, p: &Value) -> Result<Value> {
         if let Some(index) = index { super::motion::drive_joint_index(s, id, q, index)? } else { super::motion::drive_joint(s, id, q, given)? }
     };
     let sol = solution(s, &BTreeMap::new(), response_analysis(p));
-    let mut out = sol_json(&sol, p);
-    out["joint"] = json!(id);
-    out["values"] = json!(effective_values(s, id));
-    if bool_(p, "continuous") == Some(true) {
-        out["continuous"] = json!(true);
-    }
-    out["stopped_by_contact"] = r["stopped_by_contact"].clone();
-    out["stopped_by_loop"] = r["stopped_by_loop"].clone();
-    let moved = super::motion::moved(&before, &super::motion::positions(s)).next().is_some();
-    out["moved"] = json!(moved);
+    // How motion stopped, as `motion::drive_with_contact` says: an object, or null.
+    let stop = |key: &str| r.get(key).filter(|v| v.is_object()).cloned();
+    let stopped_by_contact =
+        stop("stopped_by_contact").map(serde_json::from_value::<ContactStop>).transpose().map_err(|e| bad(cmd, e.to_string()))?;
+    let stopped_by_loop = stop("stopped_by_loop").map(serde_json::from_value::<LoopStop>).transpose().map_err(|e| bad(cmd, e.to_string()))?;
+    let mut out = DriveJointResult {
+        solved: solve_report(&sol, p),
+        joint: id,
+        values: effective_value_list(s, id),
+        continuous: (bool_(p, "continuous") == Some(true)).then_some(true),
+        stopped_by_contact,
+        stopped_by_loop,
+        moved: super::motion::moved(&before, &super::motion::positions(s)).next().is_some(),
+        requested: None,
+        held: None,
+        reason: None,
+        unconnected: None,
+        param_warnings: Vec::new(),
+    };
     if let Some(j) = s.doc.assembly.joints.iter().find(|j| j.id == id) {
-        out["requested"] = json!(named_values(j, &requested));
+        out.requested = Some(named_value_list(j, &requested));
         let held = if hold { Vec::new() } else { held_values(s, j, &requested, &driven, &r) };
         if let Some(first) = held.first()
-            && !moved
+            && !out.moved
         {
-            out["reason"] = first["why"].clone();
+            out.reason = Some(first.why.clone());
         }
         if !held.is_empty() {
-            out["held"] = json!(held);
+            out.held = Some(held);
         }
     }
     if let Some((why, unconnected)) = cannot_move(s, &sol, id) {
-        out["reason"] = json!(why);
-        if let Some(o) = unconnected {
-            out["unconnected"] = json!(o);
-        }
+        out.reason = Some(why);
+        out.unconnected = unconnected;
     }
-    Ok(out)
+    reply(cmd, out)
 }
 
 /// The driven values of `j` that ended up other than `requested`, each with why: a motion link
 /// sets it from another coordinate (a screw's travel follows its turn), a limit holds it, or
 /// contact or a closed loop stopped the motion short. Degrees and mm, as `values` (#9742).
-fn held_values(s: &Session, j: &Joint, requested: &[f64], driven: &[usize], r: &Value) -> Vec<Value> {
+fn held_values(s: &Session, j: &Joint, requested: &[f64], driven: &[usize], r: &Value) -> Vec<HeldValue> {
     let now = joints::joint_values(&s.doc.assembly).remove(&j.id).unwrap_or_else(|| j.values.clone());
     let names = j.kind.dofs();
     let mut out = Vec::new();
@@ -1153,13 +1292,19 @@ fn held_values(s: &Session, j: &Joint, requested: &[f64], driven: &[usize], r: &
         } else {
             continue;
         };
-        out.push(json!({"name": name, "requested": shown(want), "value": shown(got), "unit": if angle { "deg" } else { "mm" }, "why": why}));
+        out.push(HeldValue {
+            name: name.to_string(),
+            requested: shown(want),
+            value: shown(got),
+            unit: if angle { ValueUnit::Deg } else { ValueUnit::Mm },
+            why,
+        });
     }
     out
 }
 
 /// Joints `joint.reach` takes at most in `joints`.
-const MAX_REACH_JOINTS: usize = 1000;
+pub(crate) const MAX_REACH_JOINTS: usize = 1000;
 
 fn reach(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "joint.reach";
@@ -1210,49 +1355,54 @@ fn reach(s: &mut Session, p: &Value) -> Result<Value> {
     let sol = if response_analysis(p) == joints::Analysis::Placement { place(s) } else { resolve(s) };
     let t = joints::occurrence_world(&s.doc, occ);
     let got = solidcraft_doc::apply_point(&t, at);
-    let mut out = sol_json(&sol, p);
-    out["occurrence"] = json!(occurrence_name(s, occ));
-    out["point"] = json!([got.x, got.y, got.z]);
-    out["error_mm"] = json!(got.dist(to));
     let mut there = got.dist(to) <= joints::REACH_TOL;
+    let mut error_deg = None;
     if let Some((a, z)) = axis {
         // From the sine too: the cosine alone loses small angles to rounding.
         let v = solidcraft_doc::apply_vector(&t, a);
         let deg = v.cross(z).len().atan2(v.dot(z)).to_degrees();
-        out["error_deg"] = json!(deg);
+        error_deg = Some(deg);
         there &= deg <= joints::REACH_TOL;
     }
-    out["reached"] = json!(there);
     let name = |id: u64| s.doc.assembly.joints.iter().find(|j| j.id == id);
     // As joint.list gives them: with what motion links set.
     let effective = joints::joint_values(&s.doc.assembly);
-    out["values"] = reached
+    let values = reached
         .values
         .keys()
         .filter_map(|id| name(*id))
-        .map(|j| json!({"joint": j.id, "name": j.name, "values": named_values(j, effective.get(&j.id).unwrap_or(&j.values))}))
+        .map(|j| ReachedJoint { joint: j.id, name: j.name.clone(), values: named_value_list(j, effective.get(&j.id).unwrap_or(&j.values)) })
         .collect();
-    out["moved"] = json!(super::motion::moved(&before, &super::motion::positions(s)).next().is_some());
-    out["stopped_by_limit"] = if reached.limits.is_empty() {
-        Value::Null
-    } else {
+    let stopped_by_limit = (!reached.limits.is_empty()).then(|| {
         reached
             .limits
             .iter()
             .filter_map(|(id, i, upper)| {
                 let j = name(*id)?;
-                Some(json!({"joint": j.name, "value": j.kind.dofs().get(*i), "limit": if *upper { "max" } else { "min" }}))
+                Some(LimitStop {
+                    joint: j.name.clone(),
+                    value: j.kind.dofs().get(*i).map(|d| (*d).to_string()),
+                    limit: if *upper { LimitSide::Max } else { LimitSide::Min },
+                })
             })
             .collect()
+    });
+    let result = ReachResult {
+        solved: solve_report(&sol, p),
+        occurrence: occurrence_name(s, occ),
+        point: [got.x, got.y, got.z],
+        error_mm: got.dist(to),
+        error_deg,
+        reached: there,
+        values,
+        moved: super::motion::moved(&before, &super::motion::positions(s)).next().is_some(),
+        stopped_by_limit,
+        stopped_by_loop: reached.stopped_by_loop.and_then(name).map(|j| ReachLoopStop { joint: j.name.clone() }),
+        reason: r.err(),
+        continuous: (bool_(p, "continuous") == Some(true)).then_some(true),
+        param_warnings: Vec::new(),
     };
-    out["stopped_by_loop"] = json!(reached.stopped_by_loop.and_then(name).map(|j| json!({"joint": j.name})));
-    if let Err(why) = r {
-        out["reason"] = json!(why);
-    }
-    if bool_(p, "continuous") == Some(true) {
-        out["continuous"] = json!(true);
-    }
-    Ok(out)
+    reply(cmd, result)
 }
 
 /// The centre of the box around an occurrence's bodies, in its own coordinates (its origin when
@@ -1283,7 +1433,7 @@ fn motion_link(s: &mut Session, p: &Value) -> Result<Value> {
     let ratio = ratio * ratio_scale(s, a, ia, b, ib);
     s.doc_mut().assembly.links.push(MotionLink { a, ia, b, ib, ratio, offset, coupling: None, lift: Vec::new() });
     let sol = resolve(s);
-    Ok(sol_json(&sol, p))
+    reply(cmd, SolveResult { solved: solve_report(&sol, p), param_warnings: Vec::new() })
 }
 
 /// A coupling length: a number (mm), an expression (kept as typed, so it follows the
@@ -1338,7 +1488,7 @@ fn gear(s: &mut Session, p: &Value) -> Result<Value> {
         internal: bool_(p, "internal").unwrap_or(false),
         reverse: reverse(p),
     };
-    couple(s, p, cmd, MotionLink { a, ia, b, ib, ratio: 1.0, offset: 0.0, coupling: Some(c), lift: Vec::new() })
+    reply(cmd, couple(s, p, cmd, MotionLink { a, ia, b, ib, ratio: 1.0, offset: 0.0, coupling: Some(c), lift: Vec::new() })?)
 }
 
 fn rack_pinion(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1346,7 +1496,7 @@ fn rack_pinion(s: &mut Session, p: &Value) -> Result<Value> {
     let (a, b) = joint_pair(s, p, cmd)?;
     let (ia, ib) = turn_and_travel(s, a, b, cmd)?;
     let c = Coupling::RackPinion { radius: size_param(s, p, "radius", cmd)?, reverse: reverse(p) };
-    couple(s, p, cmd, MotionLink { a, ia, b, ib, ratio: 1.0, offset: 0.0, coupling: Some(c), lift: Vec::new() })
+    reply(cmd, couple(s, p, cmd, MotionLink { a, ia, b, ib, ratio: 1.0, offset: 0.0, coupling: Some(c), lift: Vec::new() })?)
 }
 
 fn screw(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1366,7 +1516,7 @@ fn screw(s: &mut Session, p: &Value) -> Result<Value> {
         }
     };
     let c = Coupling::Screw { pitch: size_param(s, p, "pitch", cmd)?, reverse: reverse(p) };
-    couple(s, p, cmd, MotionLink { a, ia, b, ib, ratio: 1.0, offset: 0.0, coupling: Some(c), lift: Vec::new() })
+    reply(cmd, couple(s, p, cmd, MotionLink { a, ia, b, ib, ratio: 1.0, offset: 0.0, coupling: Some(c), lift: Vec::new() })?)
 }
 
 fn cam_cmd(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1400,30 +1550,32 @@ fn cam_cmd(s: &mut Session, p: &Value) -> Result<Value> {
     c.reverse = cam::default_reverse(&s.doc, &st, &probe, &c).map_err(|e| bad(cmd, e.to_string()))? != bool_(p, "flip").unwrap_or(false);
     let offset = cam::follower_offset(&s.doc, &st, &probe, &c).map_err(|e| bad(cmd, e.to_string()))?;
     let reverse = c.reverse;
-    let mut out = couple(s, p, cmd, MotionLink { coupling: Some(Coupling::Cam(c)), ..probe })?;
-    let index = out["link"].as_u64().and_then(|i| usize::try_from(i).ok()).unwrap_or(usize::MAX);
-    if let (Some(o), Some(l)) = (out.as_object_mut(), s.doc.assembly.links.get(index)) {
-        o.remove("ratio");
-        o.insert("lift".into(), lift_json(l, oscillating));
-        o.insert("reverse".into(), json!(reverse));
-        if !oscillating {
-            o.insert("follower_offset".into(), json!(offset));
-        }
-    }
-    Ok(out)
+    let coupled = couple(s, p, cmd, MotionLink { coupling: Some(Coupling::Cam(c)), ..probe })?;
+    let lift = s.doc.assembly.links.get(coupled.link).and_then(|l| lift_info(l, oscillating));
+    reply(
+        cmd,
+        CamResult {
+            solved: coupled.solved,
+            link: coupled.link,
+            lift,
+            reverse,
+            follower_offset: (!oscillating).then_some(offset),
+            param_warnings: Vec::new(),
+        },
+    )
 }
 
 /// A cam's follower travel over a turn of the cam: b's lowest and highest values and their
-/// difference, in degrees (`angle`) or mm.
-fn lift_json(l: &MotionLink, angle: bool) -> Value {
+/// difference, in degrees (`angle`) or mm; `None` for a table that is not whole.
+fn lift_info(l: &MotionLink, angle: bool) -> Option<CamLift> {
     // A table that is not whole (a hand-edited file) moves nothing, and says so.
     if l.lift.len() != cam::CAM_SAMPLES {
-        return Value::Null;
+        return None;
     }
     let unit = |v: f64| if angle { v.to_degrees() } else { v };
     let (lo, hi) = l.lift.iter().fold((f64::INFINITY, f64::NEG_INFINITY), |(lo, hi), v| (lo.min(*v), hi.max(*v)));
     let (lo, hi) = (unit(lo + l.offset), unit(hi + l.offset));
-    json!({"min": lo, "max": hi, "rise": hi - lo, "unit": if angle { "deg" } else { "mm" }})
+    Some(CamLift { min: lo, max: hi, rise: hi - lo, unit: if angle { ValueUnit::Deg } else { ValueUnit::Mm } })
 }
 
 /// A cam's profile: a sketch's closed profile (kept by its outer loop's curve ids, so the sketch's
@@ -1485,7 +1637,7 @@ fn cam_profile(s: &Session, p: &Value, cmd: &str) -> Result<CamProfile> {
 /// Add a coupling's motion link, or put it in place of link `link`: its ratio worked out from its
 /// sizes, its offset leaving b where it is (the teeth mesh as they are now), for a new link and
 /// one put in place of another alike.
-fn couple(s: &mut Session, p: &Value, cmd: &str, mut l: MotionLink) -> Result<Value> {
+fn couple(s: &mut Session, p: &Value, cmd: &str, mut l: MotionLink) -> Result<CouplingResult> {
     let links = &s.doc.assembly.links;
     let replace = match p.get("link") {
         None => None,
@@ -1538,10 +1690,7 @@ fn couple(s: &mut Session, p: &Value, cmd: &str, mut l: MotionLink) -> Result<Va
         }
     };
     let sol = resolve(s);
-    let mut out = sol_json(&sol, p);
-    out["link"] = json!(index);
-    out["ratio"] = json!(shown);
-    Ok(out)
+    Ok(CouplingResult { solved: solve_report(&sol, p), link: index, ratio: shown, param_warnings: Vec::new() })
 }
 
 fn is_angle(s: &Session, joint: u64, i: usize) -> bool {
@@ -1579,7 +1728,7 @@ fn limits(s: &mut Session, p: &Value) -> Result<Value> {
     joints::clamp(j, &mut q);
     j.values = q;
     let sol = resolve(s);
-    Ok(sol_json(&sol, p))
+    reply(cmd, SolveResult { solved: solve_report(&sol, p), param_warnings: Vec::new() })
 }
 
 fn edit(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1705,7 +1854,10 @@ fn delete(s: &mut Session, p: &Value) -> Result<Value> {
         if doc.assembly.origins.len() == before {
             return Err(bad(cmd, format!("no joint origin `{name}`")));
         }
-        return Ok(json!({"deleted_origin": name, "joints": used}));
+        return reply(
+            cmd,
+            DeleteJointResult { deleted: JointDeleted::Origin { deleted_origin: name.to_string(), joints: used }, param_warnings: Vec::new() },
+        );
     }
     if let Some(i) = num(p, "link") {
         let i = i.max(0.0) as usize;
@@ -1714,72 +1866,83 @@ fn delete(s: &mut Session, p: &Value) -> Result<Value> {
             return Err(bad(cmd, "no such motion link"));
         }
         doc.assembly.links.remove(i);
-        return Ok(json!({"deleted_link": i}));
+        return reply(cmd, DeleteJointResult { deleted: JointDeleted::Link { deleted_link: i }, param_warnings: Vec::new() });
     }
     let id = joint_id(s, p.get("joint"), cmd)?;
     delete_joints(s.doc_mut(), &[id]);
     let sol = resolve(s);
-    let mut out = sol_json(&sol, p);
-    out["deleted"] = json!(id);
-    Ok(out)
+    reply(cmd, DeleteJointResult { deleted: JointDeleted::Joint { solved: solve_report(&sol, p), deleted: id }, param_warnings: Vec::new() })
 }
 
 fn list(s: &mut Session, p: &Value) -> Result<Value> {
     let st = s.model.state();
     let sol = joints::solve(&s.doc, &st);
     let vals = joints::joint_values(&s.doc.assembly);
-    let js: Vec<Value> = s
+    let js: Vec<ListedJoint> = s
         .doc
         .assembly
         .joints
         .iter()
         .map(|j| {
-            let named = named_values(j, vals.get(&j.id).map(Vec::as_slice).unwrap_or_default());
-            let world = |o: &JointOrigin| s.doc.origin_world(&st, o).ok().map(|m| json!({"origin": [m[3][0], m[3][1], m[3][2]], "z": [m[2][0], m[2][1], m[2][2]]}));
-            let mut out = json!({"id": j.id, "name": j.name, "type": j.kind, "a": j.a.occurrence, "b": j.b.occurrence, "values": named,
-                "flip": j.flip, "offset": j.offset, "suppressed": j.suppressed, "visible": s.joint_visible(j.id), "frame_a": world(&j.a), "frame_b": world(&j.b)});
-            if !j.exprs.is_empty() {
-                out["expressions"] = json!(j.exprs);
+            let world = |o: &JointOrigin| {
+                s.doc.origin_world(&st, o).ok().map(|m| JointFrame { origin: [m[3][0], m[3][1], m[3][2]], z: [m[2][0], m[2][1], m[2][2]] })
+            };
+            ListedJoint {
+                id: j.id,
+                name: j.name.clone(),
+                kind: j.kind,
+                a: j.a.occurrence,
+                b: j.b.occurrence,
+                values: named_value_list(j, vals.get(&j.id).map(Vec::as_slice).unwrap_or_default()),
+                flip: j.flip,
+                offset: j.offset,
+                suppressed: j.suppressed,
+                visible: s.joint_visible(j.id),
+                frame_a: world(&j.a),
+                frame_b: world(&j.b),
+                expressions: (!j.exprs.is_empty()).then(|| j.exprs.clone()),
             }
-            out
         })
         .collect();
-    let links: Vec<Value> = s.doc.assembly.links.iter().map(|l| link_json(s, &st, l)).collect();
-    let origins: Vec<Value> = s.doc.assembly.origins.iter().map(|o| json!({"name": o.name, "occurrence": o.origin.occurrence})).collect();
-    let mut out = sol_json(&sol, p);
-    out["joints"] = json!(js);
-    out["links"] = json!(links);
-    out["origins"] = json!(origins);
-    out["floating"] = json!(floating_chains(s, &sol));
-    Ok(out)
+    let out = ListJointsResult {
+        solved: solve_report(&sol, p),
+        joints: js,
+        links: s.doc.assembly.links.iter().map(|l| link_info(s, &st, l)).collect(),
+        origins: s.doc.assembly.origins.iter().map(|o| ListedOrigin { name: o.name.clone(), occurrence: o.origin.occurrence }).collect(),
+        floating: floating_chains(s, &sol),
+        param_warnings: Vec::new(),
+    };
+    reply("joint.list", out)
 }
 
 /// A motion link as `joint.list` and `joint.inspect` give it: ratio per degree, offset in b's
 /// units, a coupling's definition (and why it can't be worked out), a cam's lift in place of a ratio.
-fn link_json(s: &Session, st: &solidcraft_doc::ModelState, l: &MotionLink) -> Value {
+fn link_info(s: &Session, st: &solidcraft_doc::ModelState, l: &MotionLink) -> LinkInfo {
     let angle = is_angle(s, l.b, l.ib);
     let offset = if angle { l.offset.to_degrees() } else { l.offset };
     let ratio = l.ratio / ratio_scale(s, l.a, l.ia, l.b, l.ib);
-    let mut v = json!({"a": l.a, "ia": l.ia, "b": l.b, "ib": l.ib, "ratio": ratio, "offset": offset, "unit": if angle { "deg" } else { "mm" }});
-    if let Some(c) = &l.coupling {
-        v["coupling"] = json!(c);
-        if let Some(Err(e)) = joints::coupling_values(&s.doc, st, l) {
-            v["error"] = json!(e.to_string());
-        }
-    }
     // A cam's follower follows its table, not a ratio: its travel instead.
-    if matches!(l.coupling, Some(Coupling::Cam(_)))
-        && let Some(o) = v.as_object_mut()
-    {
-        o.remove("ratio");
-        o.insert("lift".into(), lift_json(l, angle));
+    let cam = matches!(l.coupling, Some(Coupling::Cam(_)));
+    LinkInfo {
+        a: l.a,
+        ia: l.ia,
+        b: l.b,
+        ib: l.ib,
+        ratio: (!cam).then_some(ratio),
+        offset,
+        unit: if angle { ValueUnit::Deg } else { ValueUnit::Mm },
+        coupling: l.coupling.clone(),
+        error: match &l.coupling {
+            Some(_) => joints::coupling_values(&s.doc, st, l).and_then(|r| r.err()).map(|e| e.to_string()),
+            None => None,
+        },
+        lift: cam.then(|| lift_info(l, angle)),
     }
-    v
 }
 
 fn solve_cmd(s: &mut Session, p: &Value) -> Result<Value> {
     let sol = resolve(s);
-    Ok(sol_json(&sol, p))
+    reply("joint.solve", SolveResult { solved: solve_report(&sol, p), param_warnings: Vec::new() })
 }
 
 /// Index pairs `(i, j)`, `i < j`, whose boxes overlap or touch (sort and sweep along X), at most

crates/engine/src/cmd/joints_inspect.rs

@@ -3,13 +3,17 @@
 //! persistent name refers to), whether each origin is found today and why not, its kind, offset,
 //! angle, flip, limits, values, expressions and the motion links it takes part in. Reads only.
 
-use serde_json::{Value, json};
+use serde_json::Value;
 use solidcraft_doc::joints::{self, Joint, JointOrigin, Snap, XRef};
 use solidcraft_doc::naming::legacy_name;
 use solidcraft_doc::persistent_name::{Base, EdgeName, FaceName, Role};
 use solidcraft_doc::{Document, MAX_PLACEMENT_DEPTH, ModelState};
 
-use super::{component_of, joint_id, link_json, named_values, occurrence_name};
+use super::{component_of, joint_id, link_info, named_value_list, occurrence_name, reply};
+use crate::schema::joints::{
+    EdgeReference, FaceReference, InspectJointResult, InspectedJoint, JointLink, JointSide, LinkRole, MadeBy, Reference, ReferenceRole, Referent,
+    SweptFrom, WorldFrame,
+};
 use crate::{Result, Session};
 
 pub(super) fn inspect(s: &mut Session, p: &Value) -> Result<Value> {
@@ -21,7 +25,7 @@ pub(super) fn inspect(s: &mut Session, p: &Value) -> Result<Value> {
     let st = s.model.state();
     let sol = joints::solve(&s.doc, &st);
     let vals = joints::joint_values(&s.doc.assembly);
-    let out: Vec<Value> = ids
+    let out: Vec<InspectedJoint> = ids
         .iter()
         .filter_map(|id| s.doc.assembly.joints.iter().find(|j| j.id == *id))
         .map(|j| {
@@ -29,50 +33,42 @@ pub(super) fn inspect(s: &mut Session, p: &Value) -> Result<Value> {
             joint_json(s, &st, &sol, j, q)
         })
         .collect();
-    Ok(json!({ "joints": out }))
+    reply(cmd, InspectJointResult { joints: out, param_warnings: Vec::new() })
 }
 
-fn joint_json(s: &Session, st: &ModelState, sol: &joints::Solution, j: &Joint, q: &[f64]) -> Value {
-    let links: Vec<Value> = s
+fn joint_json(s: &Session, st: &ModelState, sol: &joints::Solution, j: &Joint, q: &[f64]) -> InspectedJoint {
+    let links: Vec<JointLink> = s
         .doc
         .assembly
         .links
         .iter()
         .enumerate()
         .filter(|(_, l)| l.a == j.id || l.b == j.id)
-        .map(|(i, l)| {
-            let mut v = link_json(s, st, l);
-            v["index"] = json!(i);
-            v["role"] = json!(if l.b == j.id { "driven" } else { "driver" });
-            v
-        })
+        .map(|(i, l)| JointLink { index: i, role: if l.b == j.id { LinkRole::Driven } else { LinkRole::Driver }, link: link_info(s, st, l) })
         .collect();
     let why = |list: &[(u64, String, String)]| list.iter().filter(|(id, ..)| *id == j.id).map(|(.., why)| why.clone()).collect::<Vec<_>>();
-    let mut v = json!({
-        "id": j.id,
-        "name": j.name,
-        "type": j.kind,
-        "suppressed": j.suppressed,
-        "visible": s.joint_visible(j.id),
-        "flip": j.flip,
-        "offset": j.offset,
-        "angle": j.angle.to_degrees(),
-        "values": named_values(j, q),
-        "dofs": j.kind.dofs(),
-        "a": side_json(s, st, &j.a),
-        "b": side_json(s, st, &j.b),
-        "links": links,
-        "errors": why(&sol.errors),
-        "conflicts": why(&sol.conflicts),
-    });
-    if !j.exprs.is_empty() {
-        v["expressions"] = json!(j.exprs);
+    InspectedJoint {
+        id: j.id,
+        name: j.name.clone(),
+        kind: j.kind,
+        suppressed: j.suppressed,
+        visible: s.joint_visible(j.id),
+        flip: j.flip,
+        offset: j.offset,
+        angle: j.angle.to_degrees(),
+        values: named_value_list(j, q),
+        dofs: j.kind.dofs().iter().map(|d| (*d).to_string()).collect(),
+        a: side_json(s, st, &j.a),
+        b: side_json(s, st, &j.b),
+        links,
+        errors: why(&sol.errors),
+        conflicts: why(&sol.conflicts),
+        expressions: (!j.exprs.is_empty()).then(|| j.exprs.clone()),
     }
-    v
 }
 
 /// One of a joint's origins: what it sits on, what it refers to, and where it is now.
-fn side_json(s: &Session, st: &ModelState, o: &JointOrigin) -> Value {
+fn side_json(s: &Session, st: &ModelState, o: &JointOrigin) -> JointSide {
     let component = component_of(s, o.occurrence);
     let component_name = if component == 0 {
         "root".to_string()
@@ -80,24 +76,24 @@ fn side_json(s: &Session, st: &ModelState, o: &JointOrigin) -> Value {
         s.doc.components.iter().find(|c| c.id == component).map(|c| c.name.clone()).unwrap_or_default()
     };
     let occurrence_name = if o.occurrence == 0 { "root".to_string() } else { occurrence_name(s, o.occurrence) };
-    let mut v = json!({
-        "occurrence": o.occurrence,
-        "occurrence_name": occurrence_name,
-        "component": component,
-        "component_name": component_name,
-        "path": occurrence_path(&s.doc, o.occurrence),
-        "snap": o.snap,
-        "references": references(&s.doc, &o.snap),
-    });
+    let mut v = JointSide {
+        occurrence: o.occurrence,
+        occurrence_name,
+        component,
+        component_name,
+        path: occurrence_path(&s.doc, o.occurrence),
+        snap: o.snap.clone(),
+        references: references(&s.doc, &o.snap),
+        resolves: false,
+        frame: None,
+        error: None,
+    };
     match s.doc.origin_world(st, o) {
         Ok(m) => {
-            v["resolves"] = json!(true);
-            v["frame"] = json!({"origin": [m[3][0], m[3][1], m[3][2]], "z": [m[2][0], m[2][1], m[2][2]], "x": [m[0][0], m[0][1], m[0][2]]});
-        }
-        Err(e) => {
-            v["resolves"] = json!(false);
-            v["error"] = json!(e.to_string());
+            v.resolves = true;
+            v.frame = Some(WorldFrame { origin: [m[3][0], m[3][1], m[3][2]], z: [m[2][0], m[2][1], m[2][2]], x: [m[0][0], m[0][1], m[0][2]] });
         }
+        Err(e) => v.error = Some(e.to_string()),
     }
     v
 }
@@ -118,36 +114,36 @@ fn occurrence_path(doc: &Document, occurrence: u64) -> String {
 }
 
 /// Every persistent name the snap holds, with what it refers to.
-fn references(doc: &Document, snap: &Snap) -> Vec<Value> {
+fn references(doc: &Document, snap: &Snap) -> Vec<Reference> {
     let mut out = Vec::new();
-    let mut face = |role: &str, name: &Option<String>| {
+    let mut face = |role: ReferenceRole, name: &Option<String>| {
         if let Some(n) = name {
-            out.push(with_role(role, face_ref(doc, n)));
+            out.push(Reference { role, to: Referent::Face(face_ref(doc, n)) });
         }
     };
     match snap {
         Snap::FaceCenter { face: f, x, .. } => {
-            face("face", f);
+            face(ReferenceRole::Face, f);
             if let Some(XRef::Face { face: n, .. }) = x {
-                face("x", &Some(n.clone()));
+                face(ReferenceRole::X, &Some(n.clone()));
             }
         }
         Snap::CircleCenter { face: f, end, x, .. } => {
-            face("face", f);
-            face("end", end);
+            face(ReferenceRole::Face, f);
+            face(ReferenceRole::End, end);
             if let Some(XRef::Face { face: n, .. }) = x {
-                face("x", &Some(n.clone()));
+                face(ReferenceRole::X, &Some(n.clone()));
             }
         }
         Snap::Edge { edge, face: f, corner, .. } => {
             if let Some(e) = edge {
-                out.push(with_role("edge", edge_ref(doc, e)));
+                out.push(Reference { role: ReferenceRole::Edge, to: Referent::Edge(edge_ref(doc, e)) });
             }
             if let Some(n) = f {
-                out.push(with_role("face", face_ref(doc, n)));
+                out.push(Reference { role: ReferenceRole::Face, to: Referent::Face(face_ref(doc, n)) });
             }
             if let Some(e) = corner {
-                out.push(with_role("corner", edge_ref(doc, e)));
+                out.push(Reference { role: ReferenceRole::Corner, to: Referent::Edge(edge_ref(doc, e)) });
             }
         }
         Snap::Frame { .. } | Snap::Point { .. } => {}
@@ -155,19 +151,14 @@ fn references(doc: &Document, snap: &Snap) -> Vec<Value> {
     out
 }
 
-fn with_role(role: &str, mut v: Value) -> Value {
-    v["role"] = json!(role);
-    v
-}
-
 /// What a face's persistent name refers to: `F<feature>:<role>` names the feature that made the
 /// face, and a side `side:<curve>` (or a later profile's `side:s<k>.<curve>`) the sketch curve
 /// it was swept from. Names of another form are given as they are.
-fn face_ref(doc: &Document, name: &str) -> Value {
-    let mut v = json!({ "name": name });
+fn face_ref(doc: &Document, name: &str) -> FaceReference {
+    let mut v = FaceReference { name: name.to_string(), unverified: None, role_in_feature: None, feature: None, sketch: None };
     let bare = match legacy_name(name) {
         Some(n) => {
-            v["unverified"] = json!(true);
+            v.unverified = Some(true);
             n
         }
         None => name,
@@ -175,38 +166,36 @@ fn face_ref(doc: &Document, name: &str) -> Value {
     let Ok(face) = FaceName::parse(bare) else { return v };
     let Some(fid) = face.made_by().map(|id| id.0) else { return v };
     let stem = face.stem().to_string();
-    v["role_in_feature"] = json!(stem.strip_prefix(&format!("F{fid}:")).unwrap_or(&stem));
+    v.role_in_feature = Some(stem.strip_prefix(&format!("F{fid}:")).unwrap_or(&stem).to_string());
     let Some(f) = doc.feature(fid) else {
-        v["feature"] = json!({"id": fid, "error": format!("feature {fid} is gone")});
+        v.feature = Some(MadeBy::Gone { id: fid, error: format!("feature {fid} is gone") });
         return v;
     };
-    v["feature"] = json!({"id": f.id, "name": f.name, "type": f.kind.type_name()});
+    v.feature = Some(MadeBy::Feature { id: f.id, name: f.name.clone(), kind: f.kind.type_name().to_string() });
     // A side swept from a sketch curve (a later profile's too, `side:s<k>.<curve>`).
     if let Base::Made { role: Role::Side { curve, .. }, .. } = &face.base {
         let found = f.kind.input_sketches().into_iter().find_map(|id| {
             // design-only: a joint names a curve of one of the design's sketches.
             let sk = doc.sketch(id).ok()?;
             let c = sk.curves.iter().find(|c| c.id == *curve)?;
-            let curve_type = serde_json::to_value(&c.kind).ok().and_then(|k| k.get("type").cloned()).unwrap_or(Value::Null);
+            let curve_type = serde_json::to_value(&c.kind).ok().and_then(|k| k.get("type").and_then(Value::as_str).map(str::to_string));
             let name = doc.feature(id).map(|f| f.name.clone()).unwrap_or_default();
-            Some(json!({"id": id, "name": name, "curve": curve, "curve_type": curve_type}))
+            Some(SweptFrom::Curve { id, name, curve: curve.clone(), curve_type })
         });
-        v["sketch"] = found.unwrap_or_else(|| json!({"curve": curve, "error": format!("no sketch of {} has a curve `{curve}`", f.name)}));
+        v.sketch = Some(
+            found.unwrap_or_else(|| SweptFrom::Missing { curve: curve.clone(), error: format!("no sketch of {} has a curve `{curve}`", f.name) }),
+        );
     }
     v
 }
 
 /// An edge's persistent name (`<face A>|<face B>`, `~k` for one of several between them) with
 /// what each of its faces refers to.
-fn edge_ref(doc: &Document, name: &str) -> Value {
+fn edge_ref(doc: &Document, name: &str) -> EdgeReference {
     let bare = legacy_name(name).unwrap_or(name);
-    let faces: Vec<Value> = match EdgeName::parse(bare) {
+    let faces: Vec<FaceReference> = match EdgeName::parse(bare) {
         Ok(e) => e.faces.iter().map(|f| face_ref(doc, &f.to_string())).collect(),
         Err(_) => Vec::new(),
     };
-    let mut v = json!({"name": name, "faces": faces});
-    if legacy_name(name).is_some() {
-        v["unverified"] = json!(true);
-    }
-    v
+    EdgeReference { name: name.to_string(), faces, unverified: legacy_name(name).is_some().then_some(true) }
 }

crates/engine/src/cmd/materials.rs

@@ -159,9 +159,9 @@ fn material_reply(cmd: &str, m: &UserMaterial) -> Result<MaterialReply> {
     Ok(out)
 }
 
-/// [`material_reply`] as JSON, for `material.list` (`cmd/inspect.rs`), which isn't converted yet.
-pub(super) fn material_json(m: &UserMaterial) -> Result<Value> {
-    reply("material.list", material_reply("material.list", m)?)
+/// [`material_reply`] for `material.list` (`cmd/inspect.rs`).
+pub(super) fn listed_material(m: &UserMaterial) -> Result<MaterialReply> {
+    material_reply("material.list", m)
 }
 
 fn reply(cmd: &str, reply: impl serde::Serialize) -> Result<Value> {

crates/engine/src/cmd/measure_exact.rs

@@ -3,26 +3,161 @@
 //! A curved face's area is the area of the surface it lies on: a cylinder's band is
 //! r·θ·h and a whole sphere 4πr². The display mesh's triangles run inside a curve, so
 //! their sum falls short of it.
+//!
+//! A flat face's area is the area its exact edges enclose (#12372): its outer loop's area
+//! less its holes'. The display mesh's polygon for a round hole runs inside the circle, so
+//! the mesh's holes are too small and the face reads too big.
 
 use std::f64::consts::PI;
 
 use solidcore_record::Vec3;
-use solidcore_record::brep::Curve;
+use solidcore_record::brep::{Curve, Loop};
 use solidcraft_geom::prelude::*;
 use solidcraft_geom::{Mesh, UnitVec3};
 use solidcraft_kernel::{Body, FaceSurface};
 
 /// The area of the patch of faces `patch` of `body`, worked out on the surface behind
-/// them: a cylinder's band, or a sphere. `None` where the surface does not give one, and
-/// the caller keeps the measure of the mesh.
+/// them: a flat patch, a cylinder's band, or a sphere. `None` where the surface does not
+/// give one, and the caller keeps the measure of the mesh.
 pub(crate) fn patch_area(body: &Body, mesh: &Mesh, patch: &[usize]) -> Option<f64> {
     match solidcraft_kernel::face_surface(body, *patch.first()?)? {
+        FaceSurface::Plane { normal, point } => flat_patch(body, patch, normal, point),
         FaceSurface::Cylinder { origin, axis, radius } => cylinder_band(body, mesh, patch, origin, axis, radius),
         FaceSurface::Sphere { radius, .. } => sphere(body, patch, radius),
         _ => None,
     }
 }
 
+/// Two orthonormal directions in a plane and a point on it: the plane's own 2D coordinates.
+struct PlaneFrame {
+    origin: Vec3,
+    normal: Vec3,
+    x: Vec3,
+    y: Vec3,
+}
+
+impl PlaneFrame {
+    fn new(normal: UnitVec3, origin: Vec3) -> Option<PlaneFrame> {
+        let n = normal.vec();
+        // The world axis least along the normal gives a direction across it.
+        let across = if n.x.abs() <= n.y.abs() && n.x.abs() <= n.z.abs() {
+            Vec3::X
+        } else if n.y.abs() <= n.z.abs() {
+            Vec3::Y
+        } else {
+            Vec3::Z
+        };
+        let x = n.cross(across).normalized()?;
+        Some(PlaneFrame { origin, normal: n, x, y: n.cross(x) })
+    }
+
+    /// The 2D coordinates of point `p`.
+    fn point(&self, p: Vec3) -> (f64, f64) {
+        let d = p - self.origin;
+        (d.dot(self.x), d.dot(self.y))
+    }
+
+    /// The 2D components of direction `d`.
+    fn dir(&self, d: Vec3) -> (f64, f64) {
+        (d.dot(self.x), d.dot(self.y))
+    }
+}
+
+/// The area of a flat patch: every face of it lies on one plane, and each face's area is the
+/// area its loops of exact edges enclose.
+fn flat_patch(body: &Body, patch: &[usize], normal: UnitVec3, point: Vec3) -> Option<f64> {
+    let tol = (body.size() * 1e-9).max(1e-9);
+    let frame = PlaneFrame::new(normal, point)?;
+    let mut total = 0.0;
+    for &face in patch {
+        match solidcraft_kernel::face_surface(body, face)? {
+            FaceSurface::Plane { normal: n, point: p }
+                if n.vec().dot(frame.normal).abs() >= 1.0 - 1e-9 && (p - point).dot(frame.normal).abs() <= tol => {}
+            _ => return None,
+        }
+        total += flat_face(body, face, &frame, tol)?;
+    }
+    (total.is_finite() && total > 0.0).then_some(total)
+}
+
+/// The area of flat face `face`: the area its outer loop encloses, less the areas its holes
+/// enclose. The outer loop is the one that encloses the most: every hole lies inside it.
+fn flat_face(body: &Body, face: usize, frame: &PlaneFrame, tol: f64) -> Option<f64> {
+    let mut loops: Vec<f64> = Vec::new();
+    for l in &body.record().faces.get(face)?.loops {
+        let Loop::Edges { edges } = l else { continue };
+        let mut enclosed = 0.0;
+        for used in edges {
+            enclosed += edge_sweep(body, used.edge as usize, used.forward, frame, tol)?;
+        }
+        loops.push(enclosed.abs());
+    }
+    let outer = loops.iter().copied().fold(0.0, f64::max);
+    let area = outer - (loops.iter().sum::<f64>() - outer);
+    (area.is_finite() && area > 0.0).then_some(area)
+}
+
+/// Four-point Gauss–Legendre nodes and weights on `[−1, 1]`.
+const GAUSS4: [(f64, f64); 4] = [
+    (-0.861_136_311_594_052_6, 0.347_854_845_137_453_8),
+    (-0.339_981_043_584_856_3, 0.652_145_154_862_546_2),
+    (0.339_981_043_584_856_3, 0.652_145_154_862_546_2),
+    (0.861_136_311_594_052_6, 0.347_854_845_137_453_8),
+];
+
+/// Gauss panels along an edge that is neither a line nor a circle.
+const SWEEP_PANELS: usize = 64;
+
+/// The signed area that edge `edge` sweeps about the frame's origin, `½∫(x dy − y dx)`, run
+/// along the loop's direction (`forward`: from the edge's start to its end). Summed round a
+/// loop, it is the area the loop encloses (by Green's theorem). A circle or an arc of one is
+/// worked out in closed form: the triangle to its chord and the circular segment beyond it.
+/// `None` for an edge off the plane, or one whose curve gives no derivative.
+fn edge_sweep(body: &Body, edge: usize, forward: bool, frame: &PlaneFrame, tol: f64) -> Option<f64> {
+    let triangle = |a: Vec3, b: Vec3| {
+        let ((ax, ay), (bx, by)) = (frame.point(a), frame.point(b));
+        0.5 * (ax * by - bx * ay)
+    };
+    if let Some(c) = solidcraft_kernel::edge_circle(body, edge) {
+        let along = c.axis.vec().dot(frame.normal);
+        if along.abs() < 1.0 - 1e-9 || (c.center - frame.origin).dot(frame.normal).abs() > tol {
+            return None;
+        }
+        // The arc runs counter-clockwise about its axis from its start to its end.
+        let (a, b, turn) = if forward { (c.start, c.end, along.signum()) } else { (c.end, c.start, -along.signum()) };
+        let segment = 0.5 * c.radius * c.radius * (c.angle - c.angle.sin());
+        return Some(triangle(a, b) + turn * segment);
+    }
+    let e = body.record().edges.get(edge)?;
+    if matches!(e.curve, Curve::Line { .. }) {
+        let c = solidcraft_geom::brep::eval::CurveEval::new(e.parameters()).ok()?;
+        let [t0, t1] = e.interval;
+        let (a, b) = (c.point(t0)?, c.point(t1)?);
+        let off = |p: Vec3| (p - frame.origin).dot(frame.normal).abs() > tol.max(e.tolerance);
+        if off(a) || off(b) {
+            return None;
+        }
+        return Some(if forward { triangle(a, b) } else { triangle(b, a) });
+    }
+    let c = solidcraft_geom::brep::eval::CurveEval::new(e.parameters()).ok()?;
+    let [t0, t1] = e.interval;
+    let h = (t1 - t0) / SWEEP_PANELS as f64;
+    let mut swept = 0.0;
+    for panel in 0..SWEEP_PANELS {
+        let start = t0 + h * panel as f64;
+        for (x, w) in GAUSS4 {
+            let (p, d) = c.derivs(start + 0.5 * h * (x + 1.0))?;
+            if (p - frame.origin).dot(frame.normal).abs() > tol.max(e.tolerance) {
+                return None;
+            }
+            let ((px, py), (dx, dy)) = (frame.point(p), frame.dir(d));
+            swept += 0.5 * h * w * 0.5 * (px * dy - py * dx);
+        }
+    }
+    let swept = if forward { swept } else { -swept };
+    swept.is_finite().then_some(swept)
+}
+
 /// The edges on the border of the patch: the ones a face of the patch shares with a face
 /// outside it, and the ones it keeps to itself.
 fn border_edges(mesh: &Mesh, patch: &[usize]) -> Vec<usize> {

crates/engine/src/cmd/measure_sel.rs

@@ -11,6 +11,7 @@ use solidcraft_geom::{Mesh, UnitVec3};
 
 use super::measure_shape::{Shape, Slot, add_round, centre};
 use crate::params::bad;
+use crate::schema::inspect::{MeasureKind, MeasureResult, Measured, MeasuredItems};
 use crate::{Result, Sel, Session};
 
 /// Geometry of a picked item, as points or triangles.
@@ -351,8 +352,9 @@ fn describe(s: &Session, st: &solidcraft_doc::ModelState, sel: &Sel) -> Option<I
             let patch = m.surface_patch(*index);
             let tris = patch.iter().flat_map(|f| face_tris(&m, *f)).collect::<Vec<_>>();
             let on_mesh: f64 = tris.iter().map(|[a, b, c]| (*b - *a).cross(*c - *a).len() * 0.5).sum();
-            // A curved face is measured on the surface it lies on, not on the triangles of
-            // the display mesh, which run inside the curve.
+            // A face is measured on the surface it lies on and the exact edges around it, not
+            // on the triangles of the display mesh, which run inside every curve: a curved
+            // face's and a round hole's alike.
             let area = super::measure_exact::patch_area(&b.body, &m, &patch).unwrap_or(on_mesh);
             let normals: Vec<UnitVec3> = tris.iter().filter_map(|[a, b, c]| (*b - *a).cross(*c - *a).unit()).collect();
             let planar = normals.first().copied().filter(|n0| normals.iter().all(|n| n.dot(*n0) > 1.0 - 1e-6));
@@ -456,8 +458,10 @@ fn axis_named(s: &Session, name: &str) -> Option<(Vec3, Vec3)> {
 }
 
 /// The closest points of two exact shapes, where the sampled points would be wrong: a plane or
-/// an axis runs on, so a point set of it is not the object.
-fn exact_min(a: &Shape, b: &Shape) -> Option<(f64, Vec3, Vec3)> {
+/// an axis runs on, so a point set of it is not the object. `anchor` is a point of `a` to
+/// measure from where any point would do (two parallel planes); `unbounded` says whether `a`
+/// and `b` run on for ever (datum planes and axes) rather than ending (faces and edges).
+fn exact_min(a: &Shape, b: &Shape, anchor: Option<Vec3>, unbounded: (bool, bool)) -> Option<(f64, Vec3, Vec3)> {
     use Shape::*;
     let to_plane = |p: Vec3, point: Vec3, normal: UnitVec3| {
         let n = normal.vec();
@@ -483,17 +487,7 @@ fn exact_min(a: &Shape, b: &Shape) -> Option<(f64, Vec3, Vec3)> {
         }
         (Point(p), Point(q)) => Some((p.dist(*q), *p, *q)),
         (Plane { point: p1, normal: n1 }, Plane { point: p2, normal: n2 }) => {
-            let (v1, v2) = (n1.vec(), n2.vec());
-            if v1.cross(v2).len() < 1e-9 {
-                let h = (*p2 - *p1).dot(v1);
-                Some((h.abs(), *p1, *p2 - v1 * h))
-            } else {
-                // They meet: a point on the line of intersection has distance zero.
-                let dir = v1.cross(v2);
-                let t = -(*p1 - *p2).dot(v2) / dir.dot(v2);
-                let p = *p1 + dir * t;
-                Some((0.0, p, p))
-            }
+            super::measure_shape::plane_plane(*p1, *n1, *p2, *n2, anchor.unwrap_or(*p1), unbounded.0 && unbounded.1)
         }
         (Plane { point, normal }, Line { a: la, b: lb }) => {
             let d = *lb - *la;
@@ -672,16 +666,20 @@ pub(crate) fn measure_items(s: &Session, items: &Value) -> Result<Value> {
                 .ok_or_else(|| bad(cmd, "an item can't be measured (pick vertices, edges, faces, bodies, sketch curves or profiles)"))?,
         );
     }
-    let mut out = json!({"items": described.iter().map(|d| d.json.clone()).collect::<Vec<_>>()});
+    let mut out =
+        MeasuredItems { items: described.iter().map(|d| d.json.as_object().cloned().unwrap_or_default()).collect(), ..MeasuredItems::default() };
     if let [one] = described.as_slice() {
-        for k in ["diameter", "radius", "circumference", "angle_deg", "arc_length", "center", "slot"] {
-            if let Some(v) = one.json.get(k) {
-                out[k] = v.clone();
-            }
-        }
+        let copy = |k: &str| one.json.get(k).cloned();
+        out.diameter = copy("diameter");
+        out.radius = copy("radius");
+        out.circumference = copy("circumference");
+        out.angle_deg = copy("angle_deg");
+        out.arc_length = copy("arc_length");
+        out.center = copy("center");
+        out.slot = copy("slot");
         if let Some(sl) = &one.slot {
-            out["center_from"] = json!(sl.centres.0);
-            out["center_to"] = json!(sl.centres.1);
+            out.center_from = Some(sl.centres.0.into());
+            out.center_to = Some(sl.centres.1.into());
         }
     }
     if let [a, b] = described.as_slice() {
@@ -705,39 +703,45 @@ pub(crate) fn measure_items(s: &Session, items: &Value) -> Result<Value> {
             max = Some(exact);
         }
         if let (Some((p, q)), Some(d)) = (near, min) {
-            out["distance_mm"] = json!(d);
-            out["from"] = json!(p);
-            out["to"] = json!(q);
-            out["delta"] = json!(q - p);
-            out["min"] = json!(d);
+            out.set_closest(d, p, q);
         }
-        if let Some((d, p, q)) = exact_min(&a.shape, &b.shape) {
-            out["distance_mm"] = json!(d);
-            out["from"] = json!(p);
-            out["to"] = json!(q);
-            out["delta"] = json!(q - p);
-            out["min"] = json!(d);
+        let unbounded = |i: usize| matches!(sels.get(i), Some(Sel::Plane { .. } | Sel::Axis { .. }));
+        if let Some((d, p, q)) = exact_min(&a.shape, &b.shape, near.map(|(p, _)| p), (unbounded(0), unbounded(1)))
+            .filter(|(d, p, q)| d.is_finite() && p.is_finite() && q.is_finite())
+        {
+            out.set_closest(d, p, q);
         }
         if let (Some((p, q)), Some(d)) = (far, max) {
-            out["max"] = json!(d);
-            out["max_from"] = json!(p);
-            out["max_to"] = json!(q);
-            out["max_delta"] = json!(q - p);
+            out.max = Some(d);
+            out.max_from = Some(p.into());
+            out.max_to = Some(q.into());
+            out.max_delta = Some((q - p).into());
         }
         if let Some(c) = c {
-            out["center_distance"] = json!(c.distance);
-            out["center_from"] = json!(c.from);
-            out["center_to"] = json!(c.to);
-            out["center_delta"] = json!(c.to - c.from);
+            out.center_distance = Some(c.distance);
+            out.center_from = Some(c.from.into());
+            out.center_to = Some(c.to.into());
+            out.center_delta = Some((c.to - c.from).into());
         }
-        out["measure"] = json!(if c.is_some() { "center" } else { "min" });
+        out.measure = Some(if c.is_some() { MeasureKind::Center } else { MeasureKind::Min });
         if let (Some(da), Some(db)) = (a.dir, b.dir) {
             let both_faces = matches!(sels.as_slice(), [Sel::Face { .. }, Sel::Face { .. }]);
             let cos = if both_faces { da.dot(db) } else { corner_cos(a.shape, b.shape).unwrap_or_else(|| da.dot(db).abs()) };
-            out["angle_deg"] = json!(cos.clamp(-1.0, 1.0).acos().to_degrees());
+            out.angle_deg = Some(json!(cos.clamp(-1.0, 1.0).acos().to_degrees()));
         }
     }
-    Ok(out)
+    serde_json::to_value(MeasureResult { measured: Measured::Items(Box::new(out)), param_warnings: Vec::new() }).map_err(|e| bad(cmd, e.to_string()))
+}
+
+impl MeasuredItems {
+    /// The closest distance between two items and where it is: `distance_mm` and `min` are one.
+    fn set_closest(&mut self, d: f64, p: Vec3, q: Vec3) {
+        self.distance_mm = Some(d);
+        self.min = Some(d);
+        self.from = Some(p.into());
+        self.to = Some(q.into());
+        self.delta = Some((q - p).into());
+    }
 }
 
 /// Farthest pair of points between two pieces of geometry (on their samples and vertices).

crates/engine/src/cmd/measure_shape.rs

@@ -271,6 +271,32 @@ fn from_round(a: &Shape, b: &Shape) -> Option<Centre> {
     (c.distance.is_finite() && c.from.is_finite() && c.to.is_finite()).then_some(c)
 }
 
+/// The distance between two planes, `from` on the first and `to` on the second.
+///
+/// Parallel planes (normals within 1e-6 rad, as [`parallel`] counts axes) are the
+/// perpendicular gap between them (#11833), measured from `anchor` (a point of the first item,
+/// so the dimension is drawn on it) moved onto the first plane. Planes at an angle meet: only
+/// when both run on for ever (datum planes, `meet`) is that a distance of zero on their line of
+/// intersection; a face ends, so its distance is left to its own points (`None`).
+pub(crate) fn plane_plane(p1: Vec3, n1: UnitVec3, p2: Vec3, n2: UnitVec3, anchor: Vec3, meet: bool) -> Option<(f64, Vec3, Vec3)> {
+    let (v1, v2) = (n1.vec(), n2.vec());
+    let across = v1.cross(v2);
+    if across.len() < 1e-6 {
+        let from = anchor - v1 * (anchor - p1).dot(v1);
+        let h = (from - p2).dot(v1);
+        return Some((h.abs(), from, from - v1 * h));
+    }
+    if !meet {
+        return None;
+    }
+    // The point of both planes nearest the first plane's point: from `p1` across the first
+    // plane, square to the line `n1 × n2`, until it reaches the second plane. Worked from the
+    // cross product, not `1 - (n1·n2)²`, which cancels when the planes are nearly parallel.
+    let w = across.cross(v1);
+    let p = p1 + w * ((p2 - p1).dot(v2) / across.dot(across));
+    p.is_finite().then_some((0.0, p, p))
+}
+
 /// A slot's sizes: width (the ends' diameter), the distance between the ends' centres and the
 /// overall length, with the two centres.
 #[derive(Clone, Copy, Debug, PartialEq)]
@@ -504,4 +530,42 @@ mod tests {
         assert!(slot_outline(&arcs, &skew).is_none());
         assert!(slot_outline(&[(Vec2::new(0.0, 0.0), 3.0, PI), (Vec2::new(20.0, 0.0), 4.0, PI)], &lines).is_none());
     }
+
+    /// Two walls of a box whose normals are parallel only to rounding (#11833): the gap between
+    /// the planes, from the picked point on the first to its foot on the second, never NaN.
+    #[test]
+    fn nearly_parallel_planes_measure_the_gap_between_them() {
+        let tilt = UnitVec3::new(Vec3::new(1e-8, 0.0, 1.0)).unwrap();
+        for (n2, gap) in [(UnitVec3::Z, 20.0), (-UnitVec3::Z, 20.0), (tilt, 20.0)] {
+            let anchor = Vec3::new(7.0, 3.0, 0.5);
+            let (d, from, to) = plane_plane(Vec3::new(100.0, -50.0, 0.0), UnitVec3::Z, Vec3::new(-4.0, 9.0, gap), n2, anchor, false).unwrap();
+            assert!((d - gap).abs() < 1e-6, "{n2:?}: {d}");
+            assert!(from.is_finite() && to.is_finite());
+            assert!(from.dist(Vec3::new(7.0, 3.0, 0.0)) < 1e-12, "from lies on the first plane under the pick: {from:?}");
+            assert!((to.z - gap).abs() < 1e-6 && (to - from).cross(Vec3::Z).len() < 1e-6, "to lies on the second plane: {to:?}");
+        }
+    }
+
+    /// Planes at an angle: datum planes meet (zero, on both planes); faces end, so their
+    /// distance is left to their points.
+    #[test]
+    fn planes_at_an_angle_meet_only_when_they_run_on() {
+        let (p1, p2) = (Vec3::new(0.0, 0.0, 5.0), Vec3::new(3.0, 0.0, 0.0));
+        let n2 = UnitVec3::new(Vec3::new(1.0, 0.0, 1.0)).unwrap();
+        let (d, from, to) = plane_plane(p1, UnitVec3::Z, p2, n2, p1, true).unwrap();
+        assert_eq!((d, from), (0.0, to));
+        assert!(from.is_finite() && (from.z - 5.0).abs() < 1e-12 && (from - p2).dot(n2.vec()).abs() < 1e-12, "{from:?}");
+        assert!(plane_plane(p1, UnitVec3::Z, p2, n2, p1, false).is_none());
+        assert!(plane_plane(p1, UnitVec3::Z, p2, UnitVec3::X, p1, true).is_some_and(|(_, p, _)| p.is_finite()));
+        // Just past parallel and far from the origin: the point still lies on both planes.
+        for (tilt, z1, z2) in [(2e-6, 0.0, 20.0), (2e-6, 100.0, 120.0), (1.01e-6, 1e5, 100_020.0)] {
+            let (p1, p2) = (Vec3::new(3.0, -4.0, z1), Vec3::new(-7.0, 2.0, z2));
+            let n2 = UnitVec3::new(Vec3::new(tilt, 0.0, 1.0)).unwrap();
+            let (d, p, _) = plane_plane(p1, UnitVec3::Z, p2, n2, p1, true).unwrap();
+            let scale = 1.0 + p.len();
+            assert_eq!(d, 0.0);
+            assert!((p.z - z1).abs() < 1e-9 * scale, "tilt {tilt}: {p:?} off the first plane");
+            assert!((p - p2).dot(n2.vec()).abs() < 1e-9 * scale, "tilt {tilt}: {p:?} off the second plane");
+        }
+    }
 }

crates/engine/src/cmd/mod.rs

@@ -85,8 +85,12 @@ mod point_cloud;
 mod script;
 mod section;
 pub mod settings;
+pub(crate) use clipboard::{component_path_form, copy_keys};
+pub(crate) use component::matrix::{rigid as rigid_matrix, tolerance as matrix_tolerance};
+pub(crate) use component::{base_transform, move_vector};
 pub(crate) use measure_sel::{measure_items, shape_of};
 pub(crate) use measure_shape::Shape;
+pub(crate) use script::step_params;
 #[cfg(test)]
 mod kernel_heal_tests;
 mod panels;
@@ -102,15 +106,15 @@ mod render_ui;
 mod script_tests;
 mod sheet;
 pub(crate) use sheet::{
-    FlangeType, ThenStep, flange_edge, flange_edge_list, flange_position, flange_type, fold_points, fold_position, perforation_pattern, sheet_points,
-    sheet_rule_name, then_list,
+    FlangeType, ThenStep, bend_table_format, flange_edge, flange_edge_list, flange_position, flange_type, fold_points, fold_position,
+    perforation_pattern, sheet_points, sheet_rule_name, then_list,
 };
 mod silhouette;
 mod sketch;
 pub(crate) use sketch::author_path_for_rebind;
 pub(crate) use sketch::collapse_reason;
 pub(crate) use sketch::created as sketch_created;
-pub(crate) use sketch::{PLANE_REF_FORMS, custom_plane_form};
+pub(crate) use sketch::{PLANE_REF_FORMS, custom_plane_form, point_arg_form};
 mod canvas_sketch;
 mod sketch_3d;
 mod sketch_canvas;
@@ -118,6 +122,7 @@ pub mod sketch_clipboard;
 mod sketch_constraints;
 mod sketch_construction;
 mod sketch_create;
+pub(crate) use sketch_create::{AT_MUST, MAX_TEXT_EDITS};
 mod sketch_divide;
 mod sketch_ends;
 mod sketch_equation;
@@ -126,6 +131,7 @@ mod sketch_import;
 mod sketch_inspect;
 mod sketch_modify;
 mod sketch_project;
+pub(crate) use sketch_project::{RefForm, ref_form};
 mod sketch_store;
 mod surface;
 mod surface_analysis;

crates/engine/src/cmd/motion.rs

@@ -16,8 +16,10 @@ use super::joints::{cannot_move, effective_values, joint_id, occurrence_id, plac
 use crate::params::{bad, bool_, str_, vec3};
 use crate::schema::motion::{
     ContactCheck, ContactCollision, ContactCreateParams, ContactEditParams, ContactEnableParams, ContactNoParams, ContactSetChange,
-    ContactSetCreated, ContactSetEdited, ContactSetInfo, ContactSets, ContactSwitch, FindLimitsParams, FindLimitsResult, MotionListParams,
-    MotionStudies, MotionStudyDeleteParams, MotionStudyDeleted, MotionStudyInfo, MotionStudyKeyInfo, MotionStudyParams, MotionStudySaved,
+    ContactSetCreated, ContactSetEdited, ContactSetInfo, ContactSets, ContactSwitch, ExplodeCreateParams, ExplodeCreated, ExplodeDeleteParams,
+    ExplodeDeleted, ExplodeListParams, ExplodeMoveInfo, ExplodeShowParams, ExplodeShown, ExplodeViews, ExplodedViewInfo, FindLimitsParams,
+    FindLimitsResult, MotionListParams, MotionStudies, MotionStudyDeleteParams, MotionStudyDeleted, MotionStudyInfo, MotionStudyKeyInfo,
+    MotionStudyParams, MotionStudySaved,
 };
 use crate::schema::motion_play::{
     DriveReport, ExportParams, PartPose, PlayParams, Pose, StudyExport, StudyExported, StudyPlayed, StudySample, UnmovedJoint,
@@ -53,6 +55,10 @@ const CONTACT_EDIT_CONTRACT: TypedContract<ContactEditParams> = TypedContract::n
 const STUDY_CONTRACT: TypedContract<MotionStudyParams> = TypedContract::new();
 const STUDY_DELETE_CONTRACT: TypedContract<MotionStudyDeleteParams> = TypedContract::new();
 const STUDY_LIST_CONTRACT: TypedContract<MotionListParams> = TypedContract::new();
+const EXPLODE_CREATE_CONTRACT: TypedContract<ExplodeCreateParams> = TypedContract::new();
+const EXPLODE_SHOW_CONTRACT: TypedContract<ExplodeShowParams> = TypedContract::new();
+const EXPLODE_LIST_CONTRACT: TypedContract<ExplodeListParams> = TypedContract::new();
+const EXPLODE_DELETE_CONTRACT: TypedContract<ExplodeDeleteParams> = TypedContract::new();
 const PLAY_CONTRACT: TypedContract<PlayParams> = TypedContract::new();
 const EXPORT_CONTRACT: TypedContract<ExportParams> = TypedContract::new();
 
@@ -175,16 +181,32 @@ pub static COMMANDS: &[CommandSpec] = &[
         .contract(&STUDY_DELETE_CONTRACT)
         .output(output_schema_for::<MotionStudyDeleted>)
         .params("study"),
-    CommandSpec::new("explode.create", "Exploded View", explode_create).at("SOLID", "ASSEMBLE").icon("explode").enabled(has_parts_to_explode).params(
-        "name?; scale? (automatic: each occurrence pushed away from the assembly's centre by scale × its offset, default 1); \
-         moves?: [{occurrence, translate: [x,y,z]}] (instead of automatic)",
-    ),
-    CommandSpec::new("explode.show", "Show Exploded View", explode_show)
+    CommandSpec::new("explode.create", "Exploded View", crate::checked!("explode.create", explode_create))
+        .at("SOLID", "ASSEMBLE")
+        .icon("explode")
+        .enabled(has_parts_to_explode)
+        .contract(&EXPLODE_CREATE_CONTRACT)
+        .output(output_schema_for::<ExplodeCreated>)
+        .params(
+            "name?; scale? (automatic: each occurrence pushed away from the assembly's centre by scale × its offset, default 1); \
+             moves?: [{occurrence, translate: [x,y,z]}] (instead of automatic)",
+        ),
+    CommandSpec::new("explode.show", "Show Exploded View", crate::checked!("explode.show", explode_show))
         .icon("explode")
         .noundo()
+        .contract(&EXPLODE_SHOW_CONTRACT)
+        .output(output_schema_for::<ExplodeShown>)
         .params("view: id|name (or none: back to the assembled placement) — shown only; the design keeps its placements"),
-    CommandSpec::new("explode.list", "List Exploded Views", explode_list).icon("list").noundo(),
-    CommandSpec::new("explode.delete", "Delete Exploded View", explode_delete).icon("delete").params("view"),
+    CommandSpec::new("explode.list", "List Exploded Views", crate::checked!("explode.list", explode_list))
+        .icon("list")
+        .noundo()
+        .contract(&EXPLODE_LIST_CONTRACT)
+        .output(output_schema_for::<ExplodeViews>),
+    CommandSpec::new("explode.delete", "Delete Exploded View", crate::checked!("explode.delete", explode_delete))
+        .icon("delete")
+        .contract(&EXPLODE_DELETE_CONTRACT)
+        .output(output_schema_for::<ExplodeDeleted>)
+        .params("view"),
 ];
 
 const MAX_ITEMS: usize = 10_000;
@@ -1233,7 +1255,8 @@ fn explode_create(s: &mut Session, p: &Value) -> Result<Value> {
     let name =
         str_(p, "name").map(str::to_string).unwrap_or_else(|| free_name("Exploded View", s.doc.assembly.exploded.iter().map(|v| v.name.as_str())));
     s.doc_mut().assembly.exploded.push(ExplodedView { id, name: name.clone(), moves: moves.clone() });
-    Ok(json!({"view": id, "name": name, "moves": moves.iter().map(|(o, t)| json!({"occurrence": o, "translate": t})).collect::<Vec<_>>()}))
+    let moves = moves.iter().map(ExplodeMoveInfo::from).collect();
+    typed_reply(cmd, ExplodeCreated { view: id, name, moves, param_warnings: Vec::new() })
 }
 
 fn explode_show(s: &mut Session, p: &Value) -> Result<Value> {
@@ -1242,7 +1265,7 @@ fn explode_show(s: &mut Session, p: &Value) -> Result<Value> {
         s.pending_moves.clear();
         s.exploded.clear();
         s.revision += 1;
-        return Ok(json!({"view": null}));
+        return typed_reply(cmd, ExplodeShown { view: None, name: None, param_warnings: Vec::new() });
     }
     let i = view_index(s, p, cmd)?;
     let v = s.doc.assembly.exploded.get(i).cloned().ok_or_else(|| bad(cmd, "view"))?;
@@ -1254,7 +1277,7 @@ fn explode_show(s: &mut Session, p: &Value) -> Result<Value> {
     s.exploded.clone_from(&moves);
     s.pending_moves = moves;
     s.revision += 1;
-    Ok(json!({"view": v.id, "name": v.name}))
+    typed_reply(cmd, ExplodeShown { view: Some(v.id), name: Some(v.name), param_warnings: Vec::new() })
 }
 
 /// Whether the pending moves are an exploded view shown (`explode.show`), which places the
@@ -1287,13 +1310,14 @@ fn exploded_at(moves: &[(u64, Mat, Vec3)], amount: f64) -> std::collections::BTr
 }
 
 fn explode_list(s: &mut Session, _p: &Value) -> Result<Value> {
-    Ok(json!({"views": s.doc.assembly.exploded}))
+    let views = s.doc.assembly.exploded.iter().map(ExplodedViewInfo::from).collect();
+    typed_reply("explode.list", ExplodeViews { views, param_warnings: Vec::new() })
 }
 
 fn explode_delete(s: &mut Session, p: &Value) -> Result<Value> {
     let i = view_index(s, p, "explode.delete")?;
     let v = s.doc_mut().assembly.exploded.remove(i);
-    Ok(json!({"deleted": v.name}))
+    typed_reply("explode.delete", ExplodeDeleted { deleted: v.name, param_warnings: Vec::new() })
 }
 
 /// World position of a point of an occurrence (tests).

crates/engine/src/cmd/occurrence_tests.rs

@@ -1830,6 +1830,31 @@ fn a_body_copied_in_another_design_pastes_as_an_imported_body() {
     assert!(s.model.state().body("Cube (2)").is_none());
 }
 
+/// A body pasted from another design while an exploded view moves the target component is at
+/// the world coordinates it had there once the target is shown assembled again.
+#[test]
+fn a_body_pasted_from_another_design_while_an_exploded_view_is_shown_keeps_its_world_position() {
+    let mut source = Session::default();
+    source.doc_mut().name = "Bracket".into();
+    run(&mut source, "solid.box", json!({"length": 2, "width": 2, "height": 2, "body_name": "Cube"}));
+    let was = source.world_state().unwrap().body("Cube").unwrap().mesh().bounds();
+    let copy = crate::ForeignCopy::of(&source, vec!["Cube".into()], Vec::new()).unwrap();
+
+    let mut s = Session::default();
+    run(&mut s, "solid.box", json!({"length": 1, "width": 1, "height": 1, "body_name": "Block"}));
+    let (a, a_at) = created(&mut s, "A");
+    run(&mut s, "occurrence.move", json!({"occurrence": a_at, "translate": [100,0,0]}));
+    // An exploded view needs two placements: B stays put.
+    run(&mut s, "component.create", json!({"name": "B", "parent": 0, "activate": false}));
+    let view = run(&mut s, "explode.create", json!({"moves": [{"occurrence": a_at, "translate": [0, 60, 0]}]}))["view"].as_u64().unwrap();
+    run(&mut s, "explode.show", json!({"view": view}));
+    s.foreign_copy = Some(std::sync::Arc::new(copy));
+    run(&mut s, "component.paste_from_design", json!({"component": a, "component_path": [a_at]}));
+    run(&mut s, "explode.show", json!({}));
+    let is = s.world_state().unwrap().body("Cube").unwrap().mesh().bounds();
+    assert!(was.min.dist(is.min) < 1e-6 && was.max.dist(is.max) < 1e-6, "{was:?} vs {is:?}");
+}
+
 /// A body seen in another placement of its component ("Cube (Holder:2)") pastes into another
 /// design under its own name, at that placement's position.
 #[test]

crates/engine/src/cmd/panels.rs

@@ -108,6 +108,22 @@ pub static COMMANDS: &[CommandSpec] = &[
         crate::panels::LayoutReply,
         "target or legacy id, expected_revision?: reopen retained state, activate and request focus"
     ),
+    command!(
+        "panel.focus.next",
+        "fit",
+        "Focus Next Panel",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    ),
+    command!(
+        "panel.focus.previous",
+        "fit",
+        "Focus Previous Panel",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    ),
     command!(
         "panel.list",
         "list",
@@ -124,6 +140,14 @@ pub static COMMANDS: &[CommandSpec] = &[
         crate::panels::LayoutReply,
         "target or legacy id, destination: new_section, join_tab or relative, activate?: false, expected_revision?"
     ),
+    command!(
+        "panel.move.next_zone",
+        "move",
+        "Move Panel to Next Zone",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    ),
     command!(
         "panel.native_close",
         "restore",
@@ -180,4 +204,56 @@ pub static COMMANDS: &[CommandSpec] = &[
         crate::panels::LayoutReply,
         "first, second, first_size, second_size, expected_revision?: conserve adjacent dock pair extent"
     ),
+    command!(
+        "panel.sash.down",
+        "scale",
+        "Resize Panel Sash Down",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    )
+    .key("Down"),
+    command!(
+        "panel.sash.left",
+        "scale",
+        "Resize Panel Sash Left",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    )
+    .key("Left"),
+    command!(
+        "panel.sash.reset",
+        "restore",
+        "Reset Focused Panel Sash",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    ),
+    command!(
+        "panel.sash.right",
+        "scale",
+        "Resize Panel Sash Right",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    )
+    .key("Right"),
+    command!(
+        "panel.sash.up",
+        "scale",
+        "Resize Panel Sash Up",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    )
+    .key("Up"),
+    command!(
+        "panel.toggle",
+        "fold",
+        "Toggle Focused Panel",
+        wire::Revision,
+        crate::panels::LayoutReply,
+        "expected_revision?: resolve the focused shared panel control in the live host"
+    ),
 ];