AnimationMixer uncache bug

Describe the bug

When calling the uncacheAction, uncacheClip, and uncacheRoot methods, an exception will be thrown.

To Reproduce

Steps to reproduce the behavior:

1. Load robot model in webgl_animation_skinning_morph example
2. Call the following js code
3. See error

Code

clipCtrl.onChange( function () {
	fadeToAction( api.state, 0.5 );
        // The error will appear after two seconds
	setTimeout(() => {
		mixer.uncacheRoot(model);
	}, 2000);
} );

Screenshots

Platform:

• Device: Desktop
• OS: MacOS
• Browser: Chrome
• Three.js version: r129

[mfkwgizhoujian]

Please share your code as a live example (and without any dependencies like react). It’s best to update the fiddle I have shared with my previous post: https://jsfiddle.net/hoy26z3a/2/

Sorry I can’t visit this website, and I upload the code again. This problem is very easy to reproduce. Modify the official example of threejs “webgl_animation_skinning_morph.html”, I added a timer to the state change event, and you can see the error after two seconds of state change.

[Mugen87]

It’s hard to tell whether this is a bug or the expected behavior. Meaning it’s possible that the uncache* methods should only be used after certain or all animation actions are stopped.

For now, I think it’s better to just update the documentation and mentioned the usage of stop(). If more users complain, we can still change the code.