add scaling, docs, and adjust example_mapping

README.md

@@ -1,3 +1,75 @@
 # Bevy Facial Mocap
 
-This is a project build for storyteller.ai, to provide support for importing ARKit data into bevy, and using it to drive shape keys.
+This is a project build for storyteller.ai, to provide support for importing ARKit data into bevy, and using it to drive shape keys.
+
+## Use
+
+Import the asset loader:
+
+```rust
+    app
+        .init_asset_loader::<CSVAnimationLoader>()
+```
+
+and in code, you can load assets just like any normal animation clip:
+
+```rust
+let handle = asset_server.load("recorded_test.morph_anim.json");
+let mut player = AnimationPlayer::default();
+player.play(handle.clone()).repeat();
+```
+
+## Asset Preparation
+
+To load a recording, you need 3 files:
+- a `.csv` with the ARKit data
+- a `.json` file with the mapping info
+- a `.morph_anim.json` file that points to the `.csv`, the mapping file, and provides the name of the animation root. Ideally, it would also provide an FPS - though that can be computed if it is an integer value (so not for 60 or 30, but not for 29.97)
+
+### .morph_anim.json structure
+This is the structure of the animation file itself:
+
+```json
+{
+    "csv": "./the_relative/path_to_the.csv",
+    "root_name": "pascal_Head_or_whatever_root_entity_you_want_here",
+    "fps": 4,
+    "mapping": "the_relative/path_to_the/mapping.json"
+}
+```
+
+### Mapping .json structure
+
+The mapping .json is a json list/array. Each item is a sub-list where the first element is the mapping, and the second element is the name of the morph in the CSV file.
+
+For example:
+
+```json
+[
+    ["eyeBlinkLeft", "EyeBlinkLeft"],
+    ["eyeLookDownLeft", "EyeLookDownLeft"]
+]
+```
+
+For morphs, the sub lists need to be in the same order as the morphs in the GLTF files.
+
+For bones, the first element of the sub-list is the mapping information. It provides the path to the bone (from root), the axis of the transform, and an optional offset or scale:
+
+```json
+    [{
+        "path": ["pascal_Head"],
+        "axis": "Y",
+        "scale": 0.4
+    }, "HeadYaw"],
+    [{
+        "path": ["pascal_Head"],
+        "axis": "X",
+        "offset": -45
+    }, "HeadPitch"],
+    [{
+        "path": ["pascal_Head"],
+        "axis": [0, 0, 1]
+    }, "HeadRoll"]
+```
+
+The [example_mapping.json](assets/example_mapping.json) file contains a full example of the mapping. And the [simple example](examples/simple_example.rs) contains a full code sample you can try by running `cargo run --example simple_example`.

assets/example_mapping.json

@@ -53,15 +53,18 @@
     ["tongueOut", "TongueOut"],
     [{
         "path": ["pascal_Head"],
-        "axis": "Y"
+        "axis": "Y",
+        "scale": 0.4
     }, "HeadYaw"],
     [{
         "path": ["pascal_Head"],
         "axis": "X",
-        "offset": -45
+        "offset": -22,
+        "scale": 0.4
     }, "HeadPitch"],
     [{
         "path": ["pascal_Head"],
-        "axis": "Z"
+        "axis": "Z",
+        "scale": 0.4
     }, "HeadRoll"]
 ]

src/lib.rs

@@ -293,7 +293,9 @@ impl CSVAnimation {
                 };
                 let offset = mapping.offset.unwrap_or(0f32).to_radians();
 
-                let result = result * 180f32.to_radians() + offset;
+                let scale = mapping.scale.unwrap_or(1f32);
+
+                let result = result * 180f32.to_radians() * scale + offset;
 
                 println!("Rotating {axis:?} by {result:?}");
                 println!("From {}", transform.rotation.xyz());
@@ -386,6 +388,7 @@ pub struct BoneMapping {
     path: Vec<String>,
     axis: Axis,
     offset: Option<f32>,
+    scale: Option<f32>
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]