With imported obj-files as “MorphTargets” for different facial features i'm trying to render a number of random character faces using the blendshapes SOP en noise CHOP. That works alright.

Now i want to go one step further and introduce asymmetry in the faces. For this i want to use the group parameter in the blendshape SOP's to slightly suppress the shapeblend in some parts of the face.

Somehow i can't get the group to work in the blendshape SOP.

Now i want to go one step further and introduce asymmetry in the faces.

why not halve your face into two, blend each half independently with their random noise applied, then merge and fuse it back together.

Somehow i can't get the group to work in the blendshape SOP.

it's not working in what sense? it's not doing what you'd expect? it's not taking any groups in at all? you need help figuring out a method to use groups to slightly suppress the shapeblend? clarification on that would be good..

Thnx Deecue for the reply,

That was my first thought too; to clip, mirror and merge both face halves.

And use the original blend channels to steer the other halve of the face with sligthly adjusted blends of the original halve.

Then i read in the helpfile that there was a group option in the blendshapes SOP that could be used as a “selection-mask” which, if i interp it correctly, would only pass on the blend for the selected points(?) in the group.

My plan after reading that was to make two selection groups, a left and a right part of the face. and use these to make a blend weight mask thingy effect.

I tried it first with some simple geometry but didn't get it to work.
The group had no effect and all point blends were passed on.