Vertex animation to skeletal

I need to convert vertex animation to skeletal.
I have an animated mesh (physics sim, key frames). I need to make vertex groups and attach bones to those vertex groups. Then I need to key each bone. Then apply Armature modifier to the mesh (basically rig it with the Armature that I just key framed).
The question is how do I attach each bone to corresponding vertex group?
Thanks.

Not exactly sure what you mean by “attach” a bone to a vertex group – do you mean you want to bind a certain vertex group to a certain bone so that the bone controls that vertex group’s deformation?

-OR-

Do you mean you want the bone(s) to move around according to the already-keyframed deformations of the mesh, using vertex groups you create in the mesh to control each bone?

That is precisely what I need :slight_smile:

You can’t use vertex parenting directly on a bone, but you may be able to do something similar using a combination of parenting and constraints. Here’s the thought experiment (meaning I haven’t tried it all out yet ;))

Make an Empty a child of an appropriate selection of one or three vertices in each vertex group. The Empty will then follow the parent vertices.

Put a Copy Location Constraint on a bone (it has to be unconnected from other Armature bones, of course) and use one of the child Empties as the Constraint Target.

Not sure how much absolute control over the bone location will result, or whether keying the armature will work out OK, but it’s worth trying, I think.

thanks for the tip, I’ll give it a shot

Hello! I’m interested in this procedure too, but I do not understand!
Does it works?
If I’m unlucky and I have only the model with a big set of vertex animations,

  1. how can I find the best skeletal approximation which gives a good result for all the animations?
  2. how can automatically reproduce the bones movements for each single animation without doing it one by one?

Please very simple explanations and a lot of references (technical article, math models or softwares)

Thanks

Sorry, that’s not the point of the suggestion I made above. The OP wanted to attach bones to an already vertex-animated mesh so that they would move with the mesh animations. I don’t think he was trying to imitate the vertex animations with a skeletal system.

AFAIK there’s no simple way to convert a vertex animation to skeletal. Vertex animations are “locked” into the mesh, whereas skeletal anims cause the free-to-deform mesh to move based on bone orientation – the two methods can’t be converted both ways. Making Vertex anims from skeletal is fairly simple, but the other way 'round… afaik it can’t be done directly. Only way I can think of is to create a mesh that matches the pose state of the vertex animations, rig it with an armature, and then hand-key matching moves, which isn’t what you want, I know.