public ArmatureMask removeAncestors(Joint start) {
        for (Joint cur = start; cur != null; cur = cur.getParent()) {
            int jointId = cur.getId();
            affectedJoints.clear(jointId);
        }

        return this;
    }
Remove the specified Joint and all its ancestors.

@param start the starting point (may be null, unaffected)
@return this
jme3-core/src/main/java/com/jme3/anim/ArmatureMask.java