Scene storage backend integration (#51)

This PR adds Storyteller.ai API integration for saving and loading
Storyteller Studio scenes to/from the backend.

### Known issues
* The skybox is not currently stored in the serialized scene format

studio/src/lib.rs

@@ -27,6 +27,7 @@ mod inspector;
 mod interaction;
 pub mod math;
 mod mixamo;
+mod path;
 mod persistance;
 mod remote;
 mod scene;
@@ -48,7 +49,7 @@ pub use crate::{
     mixamo::{MixamoImportEvent, MixamoPlugin},
     persistance::PersistancePlugin,
     remote::RemoteAssetPlugin,
-    scene::{LoadSceneEvent, ScenePlugin},
+    scene::{LoadLibraryObjectEvent, LoadSceneEvent, ScenePlugin},
     skybox::{SkyboxId, SkyboxPlugin},
     ui::UiLayerPlugin,
     viewport::ViewportSize,
@@ -120,8 +121,10 @@ pub fn start_viewer(
     viewport_size: ViewportSize,
 ) {
     start_internal(
-        object_id,
-        skybox_id,
+        InitSeed::FromLibrary {
+            object_id: object_id.into(),
+            skybox_id: skybox_id.into(),
+        },
         canvas_selector,
         canvas_alt,
         viewport_size,
@@ -132,15 +135,13 @@ pub fn start_viewer(
 
 #[cfg_attr(feature = "wasm", wasm_bindgen(js_name = startEditor))]
 pub fn start_editor(
-    object_id: &str,
-    skybox_id: &str,
+    scene_id: &str,
     canvas_selector: &str,
     canvas_alt: &str,
     viewport_size: ViewportSize,
 ) {
     start_internal(
-        object_id,
-        skybox_id,
+        InitSeed::FromScene(scene_id.into()),
         canvas_selector,
         canvas_alt,
         viewport_size,
@@ -158,8 +159,10 @@ pub fn start_bvh_viewer(
     viewport_size: ViewportSize,
 ) {
     let mut app = start_internal(
-        "Mannequin.gltf",
-        skybox_id,
+        InitSeed::FromLibrary {
+            object_id: "Mannequin.gltf".into(),
+            skybox_id: skybox_id.into(),
+        },
         canvas_selector,
         canvas_alt,
         viewport_size,
@@ -188,8 +191,10 @@ pub fn start_mixamo_viewer(
     viewport_size: ViewportSize,
 ) {
     let mut app = start_internal(
-        "Mannequin.gltf",
-        skybox_id,
+        InitSeed::FromLibrary {
+            object_id: "Mannequin.gltf".into(),
+            skybox_id: skybox_id.into(),
+        },
         canvas_selector,
         canvas_alt,
         viewport_size,
@@ -216,8 +221,10 @@ pub fn start(
     studio_mode: StudioMode,
 ) {
     start_internal(
-        object_id,
-        skybox_id,
+        InitSeed::FromLibrary {
+            object_id: object_id.into(),
+            skybox_id: skybox_id.into(),
+        },
         canvas_selector,
         canvas_alt,
         viewport_size,
@@ -226,13 +233,24 @@ pub fn start(
     .run();
 }
 
-// TODO: These `start_` functiions should be refactored to better support the
-//       needs of the "reaodnly viewer" vs "full studio editor" use cases. See
-//       notes in `studio-web/src/lib/viewer.element.ts` for more info.
+pub enum InitSeed {
+    /// Initialize the application from assets in the "bundled" asset library.
+    FromLibrary {
+        /// A filename, including the extension, that can be found under
+        /// `studio/assets/gltf` (e.g., "Mannequin.gltf")
+        object_id: String,
+        /// A skybox name that corresponds to a matching set of assets under
+        /// `studio/assets/skyboxes`, _not_ including file extensions or
+        /// "diffuse"/"specular" qualifiers (e.g., "gum_trees_4k")
+        skybox_id: String,
+    },
+    /// Initialize the application by loading a previously saved `*.scn.ron`
+    /// scene file.
+    FromScene(String),
+}
 
 pub fn start_internal(
-    object_id: &str,
-    skybox_id: &str,
+    seed: InitSeed,
     canvas_selector: &str,
     canvas_alt: &str,
     viewport_size: ViewportSize,
@@ -241,9 +259,6 @@ pub fn start_internal(
     #[cfg(feature = "wasm")]
     console_error_panic_hook::set_once();
 
-    let object_id = object_id.to_string();
-    let skybox_id = skybox_id.to_string();
-
     let mut app = App::new();
 
     app.insert_resource(HeadlessMode::None);
@@ -274,13 +289,25 @@ pub fn start_internal(
         app.auto_reflected_undo::<Transform>();
     }
 
-    app.add_systems(
-        Startup,
-        move |mut cmd: Commands, mut ew: EventWriter<LoadSceneEvent>| {
-            cmd.insert_resource(SkyboxId(skybox_id.clone()));
-            ew.send(LoadSceneEvent(object_id.clone()));
-        },
-    );
+    match seed {
+        InitSeed::FromLibrary {
+            object_id,
+            skybox_id,
+        } => {
+            app.add_systems(
+                Startup,
+                move |mut cmd: Commands, mut ew: EventWriter<LoadLibraryObjectEvent>| {
+                    cmd.insert_resource(SkyboxId(skybox_id.clone()));
+                    ew.send(LoadLibraryObjectEvent(object_id.clone()));
+                },
+            );
+        }
+        InitSeed::FromScene(scene) => {
+            app.add_systems(Startup, move |mut ew: EventWriter<LoadSceneEvent>| {
+                ew.send(LoadSceneEvent(scene.clone()));
+            });
+        }
+    }
 
     #[cfg(feature = "wasm")]
     wasm::initialize();
@@ -331,10 +358,10 @@ pub fn start_headless(
                 Startup,
                 move |mut cmd: Commands,
                       asset_server: Res<AssetServer>,
-                      mut ew: EventWriter<LoadSceneEvent>| {
+                      mut ew: EventWriter<LoadLibraryObjectEvent>| {
                     cmd.insert_resource(SkyboxId(skybox.clone()));
                     cmd.insert_resource(TestBvh(asset_server.load(bvh_dir.clone())));
-                    ew.send(LoadSceneEvent("Mannequin.gltf".to_string()));
+                    ew.send(LoadLibraryObjectEvent("Mannequin.gltf".to_string()));
                 },
             );