Fix skeletal animation sample() does not work as intended

[shrinktofit]

Re: cocos-creator/3d-tasks#

Changelog:

• This PR fixes:

  • The first frame of skeletal animation is not played.

  • If SkeletalAnimationState.play() is not called, the SkeletalAnimationState.sample() takes no effect. (https://forum.cocos.org/t/topic/127457/198?u=shrinktofit)

• Also optimized:

• The mesh renderer should be child of skeletal animation.

[shrinktofit]

This ensure the bake option(true vs false) of animation state is up-to-date with skinned mesh renderer, whenever.

[shrinktofit]

Before this PR: do "sync bake option" on playing.

This PR: Sync at initialize(), sync bake option each time it changes.

[YunHsiao]

Are you sure this works for both baked & sampled animations? I think the sampled branch has some init code that still needs to be executed on each play event.

[shrinktofit]

Are you sure this works for both baked & sampled animations? I think the sampled branch has some init code that still needs to be executed on each play event.

The init code of baked branch was moved to setUseBaked, which is invoked at SkeletalAnimationState.initialize() and set SkeletalAnimation.useBakedAnimation(). Is there something I missed?

[YunHsiao]

I mean what about the else branch, under real-time sampled animation mode?

[github-actions]

Interface Check Report

! WARNING this pull request has changed these public interfaces:

@@ -4117,28 +4117,23 @@
          */
         get skinningRoot(): Node | null;
         set skinningRoot(value: Node | null);
         get model(): __private._cocos_3d_models_skinning_model__SkinningModel | __private._cocos_3d_models_baked_skinning_model__BakedSkinningModel | null;
+        /**
+         * Set associated animation.
+         * @internal This method only friends to skeletal animation component.
+         */
+        associatedAnimation: SkeletalAnimation | null;
         constructor();
+        onLoad(): void;
         onDestroy(): void;
-        __preload(): void;
         uploadAnimation(clip: AnimationClip | null): void;
         /**
          * Set if bake mode should be used.
          * @internal This method only friends to skeletal animation component.
          */
         setUseBakedAnimation(val?: boolean, force?: boolean): void;
         setMaterial(material: Material | null, index: number): void;
-        /**
-         * Notifies this renderer that an animation is usable.
-         * @internal This method only friends to skeletal animation component.
-         */
-        notifyAnimationUsable(animation: SkeletalAnimation): void;
-        /**
-         * Notifies this renderer that the used animation is no longer usable.
-         * @internal This method only friends to skeletal animation component.
-         */
-        notifyAnimationUnusable(): void;
         protected _updateModelParams(): void;
     }
     /**
      * @en The skinned mesh batch renderer component, batches multiple skeleton-sharing [[SkinnedMeshRenderer]].
@@ -4230,9 +4225,12 @@
         protected _parent: SkeletalAnimation | null;
         protected _curvesInited: boolean;
         constructor(clip: AnimationClip, name?: string);
         initialize(root: Node): void;
-        onPlay(): void;
+        /**
+         * @internal This method only friends to `SkeletalAnimation`.
+         */
+        setUseBaked(useBaked: boolean): void;
         rebuildSocketCurves(sockets: Socket[]): void;
     }
     export class Socket {
         /**
@@ -4281,8 +4279,9 @@
         get useBakedAnimation(): boolean;
         set useBakedAnimation(val: boolean);
         protected _useBakedAnimation: boolean;
         protected _sockets: Socket[];
+        onLoad(): void;
         onDestroy(): void;
         start(): void;
         pause(): void;
         resume(): void;
@@ -4290,18 +4289,15 @@
         querySockets(): string[];
         rebuildSocketAnimations(): void;
         createSocket(path: string): Node | null;
         /**
-         * Adds an user which uses this animation.
          * @internal This method only friends to skinned mesh renderer.
          */
-        addUser(user: SkinnedMeshRenderer): void;
+        notifySkinnedMeshAdded(skinnedMeshRenderer: SkinnedMeshRenderer): void;
         /**
-         * Remove specific user of this animation.
-         * The user should receive an "animation useless" notification.
          * @internal This method only friends to skinned mesh renderer.
          */
-        removeUser(user: SkinnedMeshRenderer): void;
+        notifySkinnedMeshRemoved(skinnedMeshRenderer: SkinnedMeshRenderer): void;
         /**
          * Get all users.
          * @internal This method only friends to the skeleton animation state.
          */
@@ -46917,8 +46913,9 @@
         export interface _cocos_3d_skeletal_animation_skeletal_animation_utils__IAnimInfo {
             buffer: gfx.Buffer;
             data: Float32Array;
             dirty: boolean;
+            currentClip: AnimationClip | null;
         }
         export class _cocos_3d_skeletal_animation_skeletal_animation_utils__JointAnimationInfo {
             constructor(device: gfx.Device);
             getData(nodeID?: string): _cocos_3d_skeletal_animation_skeletal_animation_utils__IAnimInfo;

[shrinktofit]

Moved to below.

[shrinktofit]

@YunHsiao Please review the main fix here. I'll do the check-switch each time the animation is sampled.

[pandamicro]

This looks very strange, previously onPlay is only invoked in the beginning, but _sampleCurvesBaked is invoked in every animation frame, it just doesn't seem elegant enough

[shrinktofit]

There are two methods that trigger the sampling process:

• SkeletalAnimationState.play()/SkeletalAnimationState.resume() - Called once, do sampling every frame

• SkeletalAnimationState.sample() - Called once, do once sampling immediately.

So I captured the sampling process.

[shrinktofit]

Corresponding to https://github.com/cocos-creator/engine/pull/10006/files#diff-6b7762c60bea81084e63372b54ddae7766cb7e91ecc85de1977d3a51664bcd25R170-R181 . They should take same effect.

[pandamicro]

This looks very strange, previously onPlay is only invoked in the beginning, but _sampleCurvesBaked is invoked in every animation frame, it just doesn't seem elegant enough

[shrinktofit]

@YunHsiao