Sunday, April 14, 2013

Lip Puff Face Rigging using Sculpt Deformer Tips

Happy Sunday,
Basically I wanted the cheeks to puff.  So the tip here is to use sculpt deformer and a trick with blendshape editor to make the shapes. 

To get regions of puff we can make the sculpt deformer (using defaults) and by moving the sculpt's locator along with the sculpt sphere we can puff out just the regions we need.

The basic tip is we can use any part of a sculpted mesh to use as the blendshape.  By painting (in blendshape editor) replace of zero on all vertices, on the head with the blendshape node we get none of the blendshapes effect.  Then we can use a solid small brush and paint in replaces (ex .8, .4 .. depending on how much and where we want to use the blendshape).

I wanted to make a control quickly, so i went with expressions. So i made one channel of a locator be used for the values for the weights.  And by point constraining them to an animator control I could get the shapes controlled by animator.  Here's a short code snippet, the _loc are locators and the _blend are the lip puff blendshapes.  The min and max stuff is just so we get 0 to 1 stuff that blendshapes need to activate.

smileLip_blend.l_lipPuff = max(  0 , side_lipPuff_loc.translateX);
smileLip_blend.r_lipPuff = -1 * min(  0 , side_lipPuff_loc.translateX);
smileLip_blend.up_lipPuff = max(  0 , height_lipPuff_loc.translateX);
smileLip_blend.dn_lipPuff = -1 * min(  0 , height_lipPuff_loc.translateX);

Hope these tips were helpful.