So last night I came across a problem with the Squash/Stretch (squetch) feature of my rig. I was getting double transforms, un-scalable rigs, etc… It was a weird setup before, but I think I’ve found a solution.
The problem was I was trying to have two objects drive a single set of attributes. If the joint drives the scale XYZ of the geo (which I want so that it’s scalable), you can’t have another attribute drive the scale so that it squashes and stretches.
So, after a little trial and error, I found a solution. What I needed was more attributes, so I created a group above my geo and parent and scale constrained that to the joint. I then make a second group above my geo and make that the driven object of the squetch driver. That way, it will move and scale the geo with my joint and nothing will be double transformed because the geo’s translate isn’t being driven by anything. Also, my geometry is clean and isn’t being driven by anything, something I’ve been told to avoid.
Something to note though is that the sphere_CONST group has to be scale constrained to the highest level joint in the setup.