Three.js: The glTF model of "Polly" does not animate correctly

[cx20]

Description of the problem

The project "Polly" seems to have been created to introduce all new features of glTF 2.0.
https://www.youtube.com/watch?v=l7TB1O51X_M

However, I tried project_polly.gltf displayed in three.js + glTF Loader, skinning animation seems not to be displayed correctly.
I do not know if this is a model problem or a viewer problem.
(Because it is not displayed correctly even with Babylon.js, it may be a problem on the model side.)

Three.js + glTF Loader + project_polly.gltf result:

Three.js version

• [x] Dev
• [ ] r87
• [ ] ...

Browser

• [ ] All of them
• [x] Chrome
• [ ] Firefox
• [ ] Internet Explorer

OS

• [ ] All of them
• [x] Windows
• [ ] macOS
• [ ] Linux
• [ ] Android
• [ ] iOS

Hardware Requirements (graphics card, VR Device, ...)

ThinkPad X260 (HD Graphics 520) + Windows 10 + Chrome 61

/ping @donmccurdy
/cc @UX3D-nopper

[UX3D-nopper]

U need to investigate, when your morphing is happening. Before or after the skinning calculations.
Unfortunatelly, this is not well defined with glTF as far as I know.

[donmccurdy]

There is another issue with morph targets (#12368) also. Will try to resolve that first and then see where we're at with Polly, as the other issue is probably simpler.

[donmccurdy]

With those issues fixed, Polly's head still shrinks at intervals in the animation: https://gltf-viewer-experimental.donmccurdy.com/#model=https://raw.githubusercontent.com/KhronosGroup/glTF-Blender-Exporter/master/polly/project_polly.gltf

So, the morph target issue I mentioned is not the problem. We apply morphing before skinning calculations. Is that expected?

[donmccurdy]

The model has been updated for better support across all engines, and this problem is no longer visible.

Closing.