Help with double transforms

[Ross_Daniel]

Folks. I used mgear to do this rig however I used the classic ribbon method for the lip and brows.
I am having an issue with getting the lip and brow to scale together with the rest of the rig. Can anyone guide me as to how to parent it within the hierarchy to avoid double transforms or non-corresponding transforms when I scale the entire rig?

The rig can be downloaded here

The ribbons and follicles are in the “Deformers” group

[chrislesage]

I can’t open the rig because it uses Shapes plugin, and because Bamboo boy model is a reference, and you didn’t include it. So the rig comes in broken.

These are my general rules for making a ribbon follow properly:

• The ribbon geometry transform should not follow the hierarchy. The shape will follow the skinning or clusters you deform it with. This should help avoid double-transformation.

• For scaling, I measure and drive the scaling like this:

  • Create an empty group or locator. Let’s call it “head_scale_measure”
  • Parent head_scale_measure under a group that doesn’t move with the rig. (world space)
  • Scale constrain that group to the head. Or to the lowest node in the hierarchy that you are going to scale. So if you are going to scale the brows, scale constrain it to the brow controls.
  • The reason? By using a scale constraint, you will measure the total scale, even if the rig scales, the chest scales, and the head scales. You’ll have the final value of ALL the scaling, relative to the world group you parented it under.
  • CONNECT head_scale_measure.scaleX, scaleY and scaleZ to the scaleX, scaleY and scaleZ of each follicle’s transform node.

• If any joints are double-transforming, try turning off segmentScaleCompensation. Depending on your hierarchy, sometimes this helps. Sometimes it makes it worse. I don’t have any rules for this. I just experiment with it until it works. But basically, if you try turning off segmentScaleCompensation on your head joint, it might fix all the face joints underneath it. But that depends on your hierarchy.

[Ross_Daniel]

Thanks Chris, I updated the link in the post to download the rig.