applying morph targets on top of skinned geo

#1

hi,

im not sure if this is a stupid question or not.

i have a basic smooth skinned character. i want to raise and bend the characters arm and have the arm form the shape of a morph target mesh. I have a detailed sculpt of the arm that i want to act as the blend shape.

But i want to basically add the muscle/tendon sculpt detail of this morph target mesh on top of the skinned arm when its position gets close to the raised bent arm position. i dont want the arm mesh to be fully controlled by the blend shape, i want the arm to be positioned based on the joints and then for the extra detail in the morph target sculpt to just be added on top.

the topology on the skinned character arm section and the separate morph target arm are identical

any advice would be very helpful

thanks,
Sam

#2

It sounds like the skin_morph modifier could be what you are looking for.

#3

yea, that is more sculpting a new morph target onto the mesh when its set at a new position.

My problem is i have a seperate piece of geo which i want to use as a sort of reference morph target. But i don’t think it can work because even though the topology matches, the reference geo is already sculpted into a bent arm position, so if i copied over the sculpt somehow it would create a kind of double transform effect when i bent my characters arm and it morphed into the ref target

i think this maybe more of a scripting type problem, but i can’t get my head around it

thanks,
Sam

#4

Hey! If you’re getting double transformations you have to calculate the difference between the sculpted mesh and the skinned mesh on the desired position.

You have a few ways to do that:

  1. Use CV Shape Inverter by Chad Vernon (http://www.chadvernon.com/blog/resources/cvshapeinverter/)
    It will give you as result a mesh with only the desired corretions (something like the rest pose but with a few tweaks to it). But if you want to use corrections on top of corrections (a sculpted mesh to 90 degrees and another one to 150, for example) it seems to me that the tool can’t handle it very well. In that case I’d suggest number 2. Nice thing about this one is that creates a connected history, so whenever you tweak the sculpted mesh, it will automatically update the inverted mesh.
    ps: if you use this tool don’t forget it is a plugin, so you’d have to delete the history on the meshes in order to open the file somewhere else.

  2. Use DSL tool (http://danielslima.com/sculpt-inbetween-editor-1-0/) by Daniel S. Lima. Works perfectly, you can have multiple layers of corrections… great tool. A little harder to use it though.

  3. I think maya 2017 has this option natively now but I’m not sure about that since I wasn’t able to give it a try yet.

Then you just have to trigger the blendshape whenever you want (nodes, set driven keys, whatever).
Also, make sure the blendshape is happening before the skin cluster.
Hope it helps