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View Full Version : Sort of Auto-Weighting for Bones in Cinema possible..


wuensch
07-21-2004, 10:16 AM
Whoever is preparing animatable characters for use in Motionbuilder usually finds the hand-painting of weights for every single smart-bone very annoying.
PlugIns like bonderland or VreelWeightlifter offer Auto-weights similar to Maya or XSI to get a good start with the weights.

A workflow I developed for myself from experience with Messiah:Animate and an undocumented feature of the .fbx-exporter is the following (Dont know if someone else posted it here before),producing very nice and predictable results with Cinemas standard toolbox.:

-create the bone -skeleton for your character, do NOT use ClaudeBonnet or Vertexmaps on the skeleton, all bones are Smartbones WITHOUT absolut vertex. adjust Bone falloff-function, usually 1/r-10 works best for relative realistic figures )

- add support bones to the areas with difficult deformation (head,upper-body ribs, under armpits, hips, crotch), tweak the strength of the bones & supplementary bones until you achieve a half-decent deformation of the character. See lightwave and Messiah tutorials for info on support bone architectures.

-If you have not placed the bones as child of the mesh, unfix and make them child of the mesh, fix em. (I usually keep my mesh(es) in a NUll, making the bones affect the whole group this way through the null)

- export your boned mesh as .FBX (Important: no CB maps or Vertexmaps affecting the bones, if you have painted weights make sure they are gone for export by using Moccas ClaudeBonnets remove paint -hierarchy AND remove unused maps function.---If you still have invisible, non working CB tags in the file it will not work)

-re-import the mesh into c4d: FBX exporter has converted all the bone-falloffs into Claude-bonnet weights or Vertex-maps, depending on the setting in the preferences.
If you followed Motionbuilder naming standrd,delete the keyframes the Exporter has created on the reference-bone (Motion builder naming conventions).

-You can then go back to your actual character-file, replace the mesh & bones with the re-import, maybe drag the tag-list from the original mesh back to the re-import, or if wanted place the mesh in a null and (after unfixing) place the bones at the proper place.

-then you can finetune the Weights using your Claude Bonnet or vertexmaps.

-For Multi-part characters use this procedure for every single piece, I have not done this as I usually only use it for the main-body mesh,then adding the props weights by hand, but using Vertex maps and not CB should then enable you to assign the Vetex-maps to the appropriate bones.

I try not to make too many support bones, as for the precise areas like fingers, crotch etc. it is easier to hand-paint correct the weights to control deformation.

This workflow gives me a much better result then any autoweight and is a tremendous time-saver compared to hand-painting every single weight.


Olli

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