SkinnedMesh / Animation Support in toJSON() export

[amsi]

Was trying to understand support issues for Skinned Animation in toJSON(),

1. SkinnedMesh just a mesh with additional skeleton (array of bones) binded to it
   We just need to export this in SkinnedMesh.toJSON()?
2. Buffered geometry is already set to export bone indices and weight?
3. Bone is again just a bone in all its entirety could just have been an object3d, if no one is finicky abt it, just as target of TargetLight is
4. Are there other Animation like morphs which are an issue in toJSON() and ObjectLoader?

[Mugen87]

@amsi

SkinnedMesh just a mesh with additional skeleton (array of bones) binded to it
We just need to export this in SkinnedMesh.toJSON()?

When I recall correctly, one open issue is the fact that bones can be positioned in the scene graph at arbitrary places. They are not necessarily children of the skinned mesh which makes it impossible to export it in an isolated fashion.

@amsi

Buffered geometry is already set to export bone indices and weight?

BufferGeometry can export all kinds of attributes meaning skin indices and weights are supported, too.

@amsi

Bone is again just a bone in all its entirety could just have been an object3d, if no one is finicky abt it, just as target of TargetLight is

Not sure why you mean here. Yes, bones are just special 3d objects. The problem is not their properties but their location in the scene graph.

@amsi

Are there other Animation like morphs which are an issue in toJSON() and ObjectLoader?

Animations can’t be exported, yet see (Would like animations on models imported in the editor included on scene export · Issue #11642 · mrdoob/three.js · GitHub). One reason for this is the fact that there is no dedicated location where animations should be stored (e.g. Object3D.animations). Hence, toJSON() does not know where to look for animation clips and thus can’t serialize them.

[amsi]

@Mugen87

When I recall correctly, one open issue is the fact that bones can be positioned in the scene graph at arbitrary places. They are not necessarily children of the skinned mesh which makes it impossible to export it in an isolated fashion.

so we have an option:

1. While Importing
   We set the skeleton as a second pass, after the whole scene is set with bones in proper hierarchey

2. While Exporting
   Just use uuid of the bones for the skeleton ( the skeleton is just an array of uuids when exported in toJSON() )

I can try this and let you know if its ok !

[amsi]

I tried, and it seems to be working …