View Full Version : Problem with Parallel Blendshape on Skinned Character

10 October 2007, 04:07 PM
I have a head which is skinned to a rig and has a lot of parallel blendshapes to it. Everything works like charm in it's skinpose, but when I start rotating the neck for example, the blendshapes aren't deforming like they should. I have come across this before and that time i solved it by using a front of chain blendshape instead, but that isn't possible this time since i need to be able to blend between the different blendshape nodes without them taking each other out which is the case with front of the chain blendshapes.

Is this a limitation with parallel blendshapes that I have to live with, that they get funny deformations when they are skinned or is there a way to get around it?

Thanks in advance

10 October 2007, 04:24 PM
Its probably to do with having your skinCluster node above your blendShape nodes in the input order.

Right click your bound mesh, goto inputs--> All Inpurts. Then middle mouse drag the blendshapes below the skinCluster.

If that doesn't fix it then someone else maybe able to help you, i've not done any creature work in ages and can't remember the specific blendshape settings off the top of my head.

10 October 2007, 05:08 PM
Thanks for you quick reply but I don't think that is quite the issue. I think you're thinking about when you put like a default blendshape on after the skinning which makes the mesh ignore the skinning when the blendshape is in effect. Putting the skinning before the blendshape in the deformation order.

My blendshapes and skinning is working together, it's just that the parallel blendshape is blending the blendshapes in a weird way when the joints to which it's skinned is rotating. I'm guessing it has something to do with how the parallel blendshapes are blending between each other and the skinning. If that's the case I'm gonna have to find a workaround.

10 October 2007, 05:17 PM
it has to do with how the skincluster works

the skincluster changes the local space in which your vertices lie. so, when you create a blendshape, it doesn't take that change of space into account. meaning that when you would use those blendshapes without a skincluster, all would be well, but when you apply the blendshape after a skincluster the deformations will behave funky since the transformations are happening in a different space than the one in which they were created.

christian breitling wrote a plugin for it, it's not supported for 2008 yet as far as I know, you can find it here.

10 October 2007, 12:01 AM
So all my blendshapes are a waste and i have to make new ones? Hmm, not sure if you understood completely but I will check that script out. Thanks.

10 October 2007, 12:34 AM
Ok, to clarify the problem. I think I explain pretty much the problem here :) Hope someone can enlighten me :)

10 October 2007, 01:00 AM
And again, the reason why I can't us front of chain is because i need to be able to blend between different blendshapes. Otherwise I would have chosen that but I need this to work with parallel!

10 October 2007, 02:26 PM
Maybe I dont completely understand what you are trying to do, but here is a suggestion anyway.

You could make a front-of-chain blendshape using only one target which is just a copy of your undeformed mesh and set the slider to 1. Then deform that target using your parallel blendshapes. So that first target is a kind of intermediate that takes the result of your parallel shapes and applies it to your skinned mesh.

-- David

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10 October 2007, 02:26 PM
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