Thursday, April 3, 2014

3DS Max CAT Gimbal problem - Solution!

Recently, I've been looking for a way to fix this, and no where did I find a solution... So I analyzed the CAT tools, and finally, I discovered the solution that WORKS!

I will explain the first problem, a simple solution to the first problem, a second MAJOR problem, and a somewhat complex (but built-in to CAT's tools) solution:


Problem 1: A CAT-rigged character with a T-pose in Max will not have a properly working spine control.  Whenever the hips rotate, so does the spine.

Solution 1:

  1. Select the Chest Control
  2. Under Hierarchy>Link Info>Bone Hierarchy>Inheritance>Animation Mode, turn off "Inherit Rotation".  This will allow separate rotation between the hips and spine.


Problem 2: When "Inherit Rotation" is turned off, the rotation tools in the Viewport work perfectly, but once in the Graph Editor, both X and Z rotation are flat on top of each other and must be counter-animated, also known as a Gimbal Lock.

Solution 2:

  1. Select the Chest Control
  2. Hierarchy>Link Info>Bone Hierarchy>Inheritance>Animation Mode
    • Turn ON "Inherit Rotation" (undo what was done in Solution 1).
  3. Hierarchy>Link Info>Inherit>Rotate, turn OFF X, Y, and Z.
  4. Motion>Euler Parameters
    1. Axis Order: YZX
    2. Rotation Axis: Y

If you work a lot using the graph editor, you will immediately notice how much faster your workflow will be.  Enjoy!