Working With Muscles

In CAT, muscles are non-rendering helper objects that you can use to create a skin that looks realistic when stretched and deformed.

For example, the following illustration shows how the Marama rig's shoulder and upper arm have collapsed after being twisted and pulled in various directions. (Marama is one of the standard CATRigs included with CAT.)

Marama's shoulder will behave better once we finish applying the CATMuscle to her CATBones.

That happened because Marama's rigging includes no muscle objects; the skin shape is determined by the relative positions of the CATBones.

In the illustration, the purple patches are the segments of a CATMuscle that was created and shaped to use as muscles for her pectorals and shoulder. To complete the job, you would:

Muscle Types

As the Create panel shows, you can create two kinds of muscles:


The muscle objects in CAT are designed to be used in three ways: