Maya slide controls over surface/skull?

Rigging
1

hey everybody!

I’m currently working on a facial setup for a relly weird looking character! I decided to go for a joint based setup as opposed to blendshapes as there is still a lot of experimentation to be done on this face, Anyway. I wanted to set up the joints to slide over underlying skull geometry, with the option of grabbing a control underneath and having a level of free manipulation.

for the sliding I thought I’d use the geometry constraint, but I find it to be highly inaccurate. as the oobjects position is stored in world space and then snapped to the surface. This often leads to unpredictable results moving the controls. For now I have settled to using a pointOnSurface node and Driving the U and V values via another controls translation, but what I really want is a way to constrain an object to a surface, with accurate controls (U/V values) but the ability to manually move it oon the surface like with the geometry constraint.

Has anyone an idea how to solve that?

cheers,

Alex

2

pointOnSurface and closestPointOnSurface are your friend to build your own version of a stable geometry constraint.

3

Yeah, that’s what I’m using at the moment. i was just hoping to find a way to have the animator pick the control object, and move it around like every other control object on my rig, but with it following the surface while moving.

It’s working OK with the closestPointOnSurface but the controller itself still doesn’t slide over the surface!

Thanks for the tip anyway :wink:

4

You can try and hook it up to the pivot, a system like that could work as if the actual control is sliding, although cycles might be hard to avoid.