fix dynamic bone animations

lib/animations/bone_animation_data.dart

@@ -9,9 +9,9 @@ import 'package:vector_math/vector_math.dart';
 ///
 class BoneAnimationData {
   final String boneName;
-  final String meshName;
+  final List<String> meshNames;
   final Float32List frameData;
   double frameLengthInMs;
   BoneAnimationData(
-      this.boneName, this.meshName, this.frameData, this.frameLengthInMs);
+      this.boneName, this.meshNames, this.frameData, this.frameLengthInMs);
 }

lib/animations/bone_driver.dart

@@ -46,11 +46,21 @@ class BoneDriver {
         rotation.x *= weight;
         rotation.y *= weight;
         rotation.z *= weight;
+        rotation.w = 1;
+
         return rotation;
       }).toList();
 
-      yield rotations.fold(
-          rotations.first, (Quaternion a, Quaternion b) => a * b);
+      if (frameNum == 0) {
+        print(rotations);
+      }
+
+      var result = rotations.fold(
+          rotations.first, (Quaternion a, Quaternion b) => a + b);
+      result.w = 1;
+      print("RESULT $result");
+      yield result;
+      // .normalized();
       // todo - bone translations
     }
   }

lib/animations/csv_animation.dart

@@ -11,11 +11,12 @@ import 'package:vector_math/vector_math.dart';
 /// A class for loading animation data from a single CSV and allocating between morph/bone animation with help.
 ///
 class DynamicAnimation {
-  final MorphAnimationData morphAnimation;
+  final MorphAnimationData? morphAnimation;
   final List<BoneAnimationData> boneAnimation;
 
-  factory DynamicAnimation.load(String meshName, String csvPath,
+  factory DynamicAnimation.load(String? meshName, String csvPath,
       {List<BoneDriver>? boneDrivers,
+      List<String>? boneMeshes,
       String? boneDriverConfigPath,
       double? framerate}) {
     // create a MorphAnimationData instance from the given CSV
@@ -23,8 +24,9 @@ class DynamicAnimation {
     var frameLengthInMs = 1000 / (framerate ?? 60.0);
     var morphNames = llf
         .item1; //.where((name) => !boneDrivers.any((element) => element.blendshape == name));
-    var morphAnimationData =
-        MorphAnimationData(meshName, llf.item2, morphNames, frameLengthInMs);
+
+    var morphAnimationData = MorphAnimationData(
+        meshName ?? "NULL", llf.item2, morphNames, frameLengthInMs);
 
     final boneAnimations = <BoneAnimationData>[];
 
@@ -45,14 +47,14 @@ class DynamicAnimation {
     // iterate over every bone driver
     if (boneDrivers != null) {
       for (var driver in boneDrivers) {
-        // get all frames for the single the blendshape
+        // collect the frame data for the blendshapes that this driver uses
         var morphData = driver.transformations
             .map((String blendshape, Transformation transformation) {
           return MapEntry(
               blendshape, morphAnimationData.getData(blendshape).toList());
         });
 
-        // apply the driver to the blendshape weight
+        // apply the driver to the frame data
         var transformedQ = driver.transform(morphData).toList();
 
         // transform the quaternion to a Float32List
@@ -60,7 +62,7 @@ class DynamicAnimation {
 
         // add to the list of boneAnimations
         boneAnimations.add(BoneAnimationData(
-            driver.bone, meshName, transformedF, frameLengthInMs));
+            driver.bone, boneMeshes!, transformedF, frameLengthInMs));
       }
     }
 

lib/animations/live_link_face_bone_driver.dart

@@ -5,8 +5,9 @@ import 'package:vector_math/vector_math.dart';
 
 BoneDriver getLiveLinkFaceBoneDrivers(String bone) {
   return BoneDriver(bone, {
-    "HeadPitch": Transformation(Quaternion.axisAngle(Vector3(1, 0, 0), pi / 2)),
-    "HeadRoll": Transformation(Quaternion.axisAngle(Vector3(0, 0, 1), pi / 2)),
+    "HeadPitch":
+        Transformation(Quaternion.axisAngle(Vector3(0, 0, -1), pi / 3)),
+    "HeadRoll": Transformation(Quaternion.axisAngle(Vector3(1, 0, 0), pi / 2)),
     "HeadYaw": Transformation(Quaternion.axisAngle(Vector3(0, 1, 0), pi / 2)),
   });
 }

lib/filament_controller.dart

@@ -320,32 +320,26 @@ class FilamentController {
   /// Animates morph target weights/bone transforms (where each frame requires a duration of [frameLengthInMs].
   /// [morphWeights] is a list of doubles in frame-major format.
   /// Each frame is [numWeights] in length, and each entry is the weight to be applied to the morph target located at that index in the mesh primitive at that frame.
+  /// for now we only allow animating a single bone (though multiple skinned targets are supported)
   ///
   void setBoneAnimation(
-      FilamentEntity asset, List<BoneAnimationData> animations) async {
-    // for future compatibility, instances of BoneAnimationData can specify individual mesh targets
-    // however on the rendering side we currently only allow one set of frame data for one mesh target (though multiple bones are supported).
-    // this is a check that all animations are targeting the same mesh
-    assert(animations.map((e) => e.meshName).toSet().length == 1);
-
-    var data =
-        calloc<Float>(animations.length * animations.first.frameData.length);
+      FilamentEntity asset, BoneAnimationData animation) async {
+    var data = calloc<Float>(animation.frameData.length);
     int offset = 0;
-    var numFrames = animations.first.frameData.length ~/ 7;
-    var boneNames = calloc<Pointer<Char>>(animations.length);
-    int animIdx = 0;
-    for (var animation in animations) {
-      if (animation.frameData.length ~/ 7 != numFrames) {
-        throw Exception(
-            "All bone animations must share the same animation frame data length.");
-      }
-      for (int i = 0; i < animation.frameData.length; i++) {
-        data.elementAt(offset).value = animation.frameData[i];
-        offset += 1;
-      }
-      boneNames.elementAt(animIdx).value =
-          animation.boneName.toNativeUtf8().cast<Char>();
-      animIdx++;
+    var numFrames = animation.frameData.length ~/ 7;
+    var boneNames = calloc<Pointer<Char>>(1);
+    boneNames.elementAt(0).value =
+        animation.boneName.toNativeUtf8().cast<Char>();
+
+    var meshNames = calloc<Pointer<Char>>(animation.meshNames.length);
+    for (int i = 0; i < animation.meshNames.length; i++) {
+      meshNames.elementAt(i).value =
+          animation.meshNames[i].toNativeUtf8().cast<Char>();
+    }
+
+    for (int i = 0; i < animation.frameData.length; i++) {
+      data.elementAt(offset).value = animation.frameData[i];
+      offset += 1;
     }
 
     _nativeLibrary.set_bone_animation(
@@ -353,10 +347,11 @@ class FilamentController {
         asset,
         data,
         numFrames,
-        animations.length,
+        1,
         boneNames,
-        animations.first.meshName.toNativeUtf8().cast<Char>(),
-        animations.first.frameLengthInMs);
+        meshNames,
+        animation.meshNames.length,
+        animation.frameLengthInMs);
     calloc.free(data);
   }
 

lib/generated_bindings.dart

@@ -659,7 +659,8 @@ class NativeLibrary {
     int numFrames,
     int numBones,
     ffi.Pointer<ffi.Pointer<ffi.Char>> boneNames,
-    ffi.Pointer<ffi.Char> meshName,
+    ffi.Pointer<ffi.Pointer<ffi.Char>> meshName,
+    int numMeshTargets,
     double frameLengthInMs,
   ) {
     return _set_bone_animation(
@@ -670,6 +671,7 @@ class NativeLibrary {
       numBones,
       boneNames,
       meshName,
+      numMeshTargets,
       frameLengthInMs,
     );
   }
@@ -683,7 +685,8 @@ class NativeLibrary {
               ffi.Int,
               ffi.Int,
               ffi.Pointer<ffi.Pointer<ffi.Char>>,
-              ffi.Pointer<ffi.Char>,
+              ffi.Pointer<ffi.Pointer<ffi.Char>>,
+              ffi.Int,
               ffi.Float)>>('set_bone_animation');
   late final _set_bone_animation = _set_bone_animationPtr.asFunction<
       void Function(
@@ -693,7 +696,8 @@ class NativeLibrary {
           int,
           int,
           ffi.Pointer<ffi.Pointer<ffi.Char>>,
-          ffi.Pointer<ffi.Char>,
+          ffi.Pointer<ffi.Pointer<ffi.Char>>,
+          int,
           double)>();
 
   void play_animation(