Retopology on animated rig?

TripleJ

I've been provided with a rig in a .max scene file that has already been rigged and animated. I don't know Max at all so I sent the file to Maya as an .fbx.

The model is still too high poly to be included in game, so is there any way to reduce the poly count while preserving the animation? Or am I out of luck?

Froyok

Well if you work in maya, you can do the retopo and then transfer the skinweight from the HP to your retopo. I don't think it will be perfect but 90% of the work will be saved imho.

JohnnyRaptor

Yeah, what Froyok said.

In maya, you can also transfer weights by UVs, so if your HP is unwrapped, and you maintain the UVs on the lowpoly, your skinweight transfer should be a lot more accurate.

Froyok

There is also a lot of maya scripts to save and re-project the skinweight based on the local/world space instead of the vertex position. It can maybe be better than the maya tools.

Mark Dygert

In max you copy your mesh, do your edits and then apply the skinwrap modifier and target the original mesh. Skinwrap uses the vert postion and weighting on the original mesh to look for a vert roughly in the same position on the new mesh and have it follow along.

Normally I animate the rig into extreme poses while skinwrap is applied and tweak the settings a bit to make sure the deformation is as close as possible to the original.

Then inside of skinwrap there is a "convert to skin" option, click that and the weights will transfer. You can then delete the original mesh and the skinwrap modifier from the stack.

There might be some clean up work depending on what you did to the mesh and how far you moved verts from their original position but for the vast majority of verts that didn't move this will save a lot of time.


TLDR

1. Copy mesh, collapse stack, make edits
2. Skinwrap, target original mesh
3. Animate extreme poses, tweak skinwrap settings
4. Skinwrap, convert to skin
5. Delete original mesh and skinwrap modifier

poopipe

yeah. in max this is easy, safe and relatively painless provided you have a bind pose to work off.
in maya, i would imagine its similar.


provided you have the bind pose stored you're laughing

TripleJ

Thanks all, I have it working now.