Merge pull request #8802 from Drigax/fix-babylon-skinned-animation-from-gltf

Fix for .babylon exported gltf meshes having improper deformation

dist/preview release/what's new.md

@@ -292,6 +292,7 @@
 - Fix the bounding box of instances that does not match the instance position / rotation / scaling ([Popov72](https://github.com/Popov72))
 - Fix an issue with sound updateOptions not updating the underlying sound buffer/html element ([RaananW](https://github.com/RaananW))
 - Fixed bug in sphereBuilder where top and bottom segments added 6 indices per triangle instead of 3. ([aWeirdo](https://github.com/aWeirdo))
+- Fixed issue with Babylon scene export of loaded glTF meshes.([Drigax]/(https://github.com/drigax))
 
 ## Breaking changes
 - `FollowCamera.target` was renamed to `FollowCamera.meshTarget` to not be in conflict with `TargetCamera.target` ([Deltakosh](https://github.com/deltakosh))

src/Bones/skeleton.ts

@@ -66,6 +66,9 @@ export class Skeleton implements IAnimatable {
     /** @hidden */
     public _hasWaitingData: Nullable<boolean> = null;
 
+    /** @hidden */
+    public _waitingOverrideMeshId: Nullable<string> = null;
+
     /**
      * Specifies if the skeleton should be serialized
      */
@@ -706,6 +709,7 @@ export class Skeleton implements IAnimatable {
         serializationObject.bones = [];
 
         serializationObject.needInitialSkinMatrix = this.needInitialSkinMatrix;
+        serializationObject.overrideMeshId = this.overrideMesh?.id;
 
         for (var index = 0; index < this.bones.length; index++) {
             var bone = this.bones[index];
@@ -713,9 +717,11 @@ export class Skeleton implements IAnimatable {
 
             var serializedBone: any = {
                 parentBoneIndex: parent ? this.bones.indexOf(parent) : -1,
+                index: bone.getIndex(),
                 name: bone.name,
                 matrix: bone.getBaseMatrix().toArray(),
-                rest: bone.getRestPose().toArray()
+                rest: bone.getRestPose().toArray(),
+                linkedTransformNodeId: bone.getTransformNode()?.id
             };
 
             serializationObject.bones.push(serializedBone);
@@ -764,16 +770,22 @@ export class Skeleton implements IAnimatable {
 
         skeleton.needInitialSkinMatrix = parsedSkeleton.needInitialSkinMatrix;
 
+        if (parsedSkeleton.overrideMeshId) {
+            skeleton._hasWaitingData = true;
+            skeleton._waitingOverrideMeshId = parsedSkeleton.overrideMeshId;
+        }
+
         let index: number;
         for (index = 0; index < parsedSkeleton.bones.length; index++) {
             var parsedBone = parsedSkeleton.bones[index];
-
+            var parsedBoneIndex = parsedSkeleton.bones[index].index;
             var parentBone = null;
             if (parsedBone.parentBoneIndex > -1) {
                 parentBone = skeleton.bones[parsedBone.parentBoneIndex];
             }
+
             var rest: Nullable<Matrix> = parsedBone.rest ? Matrix.FromArray(parsedBone.rest) : null;
-            var bone = new Bone(parsedBone.name, skeleton, parentBone, Matrix.FromArray(parsedBone.matrix), rest);
+            var bone = new Bone(parsedBone.name, skeleton, parentBone, Matrix.FromArray(parsedBone.matrix), rest, null, parsedBoneIndex);
 
             if (parsedBone.id !== undefined && parsedBone.id !== null) {
                 bone.id = parsedBone.id;

src/Loading/Plugins/babylonFileLoader.ts

@@ -391,6 +391,11 @@ var loadAssetContainer = (scene: Scene, data: string, rootUrl: string, onError?:
                         }
                     });
                 }
+
+                if (skeleton._waitingOverrideMeshId) {
+                    skeleton.overrideMesh = scene.getMeshByID(skeleton._waitingOverrideMeshId);
+                    skeleton._waitingOverrideMeshId = null;
+                }
                 skeleton._hasWaitingData = null;
             }
         }
@@ -633,6 +638,12 @@ SceneLoader.RegisterPlugin({
                                 }
                             });
                         }
+
+                        if (skeleton._waitingOverrideMeshId) {
+                            skeleton.overrideMesh = scene.getMeshByID(skeleton._waitingOverrideMeshId);
+                            skeleton._waitingOverrideMeshId = null;
+                        }
+
                         skeleton._hasWaitingData = null;
                     }
                 }

src/Meshes/mesh.ts

@@ -3085,6 +3085,7 @@ export class Mesh extends AbstractMesh implements IGetSetVerticesData {
         // Skeleton
         if (this.skeleton) {
             serializationObject.skeletonId = this.skeleton.id;
+            serializationObject.numBoneInfluencers = this.numBoneInfluencers;
         }
 
         // Physics
@@ -3454,7 +3455,7 @@ export class Mesh extends AbstractMesh implements IGetSetVerticesData {
         }
 
         // Skeleton
-        if (parsedMesh.skeletonId > -1) {
+        if (parsedMesh.skeletonId !== undefined && parsedMesh.skeletonId !== null) {
             mesh.skeleton = scene.getLastSkeletonByID(parsedMesh.skeletonId);
             if (parsedMesh.numBoneInfluencers) {
                 mesh.numBoneInfluencers = parsedMesh.numBoneInfluencers;