Initial work on ledge & improved baking of root motion. (#90)

Reviewed-on: #90
Co-authored-by: Álex Román Núñez <eirexe@eirteam.moe>

src/fighter/baked_animation/asset_baking.rs

@@ -27,6 +27,7 @@ struct FighterBakeSource {
     model_bytes: Vec<u8>,
     buffers: Vec<Vec<u8>>,
     animations: HashMap<AnimKind, String>,
+    root_motion_bone: String,
 }
 #[derive(Default, TypePath)]
 struct FighterBakeSourceLoader;
@@ -82,6 +83,7 @@ impl AssetLoader for FighterBakeSourceLoader {
             model_bytes,
             buffers,
             animations: manifest.animations,
+            root_motion_bone: manifest.root_motion_bone,
         })
     }
     fn extensions(&self) -> &[&str] {
@@ -123,7 +125,12 @@ impl AssetTransformer for FighterBakeTransformer {
         source: TransformedAsset<Self::AssetInput>,
         _: &'a Self::Settings,
     ) -> Result<TransformedAsset<Self::AssetOutput>, Self::Error> {
-        let baked = bake_gltf(&source.model_bytes, &source.buffers, &source.animations)?;
+        let baked = bake_gltf(
+            &source.model_bytes,
+            &source.buffers,
+            &source.animations,
+            &source.root_motion_bone,
+        )?;
         Ok(source.replace_asset(baked))
     }
 }
@@ -201,6 +208,7 @@ fn bake_gltf(
     bytes: &[u8],
     buffer_bytes: &[Vec<u8>],
     animations: &HashMap<AnimKind, String>,
+    root_motion_bone: &str,
 ) -> io::Result<BakedFighterAnimations> {
     let gltf = gltf::Gltf::from_slice(bytes)
         .map_err(|error| io::Error::new(io::ErrorKind::InvalidData, error))?;
@@ -228,13 +236,14 @@ fn bake_gltf(
             "glTF buffer data is incomplete",
         ));
     }
-    bake_gltf_document(gltf.document, buffers, animations)
+    bake_gltf_document(gltf.document, buffers, animations, root_motion_bone)
 }
 
 pub(super) fn bake_gltf_document(
     document: gltf::Document,
     buffers: Vec<gltf::buffer::Data>,
     animations: &HashMap<AnimKind, String>,
+    root_motion_bone: &str,
 ) -> io::Result<BakedFighterAnimations> {
     let nodes: Vec<_> = document.nodes().collect();
     if nodes.is_empty() {
@@ -260,6 +269,15 @@ pub(super) fn bake_gltf_document(
             })
         })
         .collect::<io::Result<Vec<_>>>()?;
+    let root_bone_index = names
+        .iter()
+        .position(|name| name == root_motion_bone)
+        .ok_or_else(|| {
+            io::Error::new(
+                io::ErrorKind::InvalidData,
+                format!("fighter model has no root-motion bone named {root_motion_bone}"),
+            )
+        })?;
     let mut pending = HashMap::<&str, Vec<AnimKind>>::new();
     for (kind, name) in animations {
         pending.entry(name).or_default().push(*kind);
@@ -286,17 +304,28 @@ pub(super) fn bake_gltf_document(
             .fold(0.0_f32, f32::max);
         let frame_count = baked_frame_count(duration, BAKED_ANIMATION_FPS);
         let mut frames = Vec::with_capacity(frame_count);
+        let mut root_positions = Vec::with_capacity(frame_count);
         for frame in 0..frame_count {
             let time = (frame as f32 / BAKED_ANIMATION_FPS as f32).min(duration);
-            frames.push(
-                nodes
-                    .iter()
-                    .map(|node| local_transform(node.clone(), &channels, time))
-                    .collect::<io::Result<Vec<_>>>()?,
-            );
+            let local = nodes
+                .iter()
+                .map(|node| local_transform(node.clone(), &channels, time))
+                .collect::<io::Result<Vec<_>>>()?;
+            let mut model = vec![None; local.len()];
+            let root = super::runtime::resolve_model_transform(
+                root_bone_index,
+                &parents,
+                &local,
+                &mut model,
+            )?;
+            root_positions.push(root.get_translation());
+            frames.push(local);
         }
         let index = clips.len();
-        clips.push(BakedAnimationClip { frames });
+        clips.push(BakedAnimationClip {
+            frames,
+            root_positions,
+        });
         for kind in kinds {
             clip_indices.insert(kind, index);
         }
@@ -322,6 +351,7 @@ pub(super) fn bake_gltf_document(
         frame_rate: BAKED_ANIMATION_FPS,
         bone_names: names,
         parents,
+        root_bone_index,
         clips,
         clip_indices,
     })