How do we move a skinned joint, and then reset the mesh back to its original bind pose, while keeping the joint in its new position/orient?
joint.matrix
Position of the joint in parent space
joint.inverseMatrix
takes you back to the position of the parent
joint.parentMatrix
Position of the joint's parent in world space
joint.parentInverseMatrix
takes you back to the position of the joint's parent in world space
joint.worldMatrix
position of the joint in world space as represented by matrix
joint.worldInverseMatrix
The '.worldInverseMatrix' of the joint is basically the matrix info for the current moved position. (ie, the transform information?-- no, more like the distance of the object from the origin.. or what you would have to do to the matrix to get back to the origin (identity matrix))
BindPreMatrix?
skinCluster.bindPreMatrix has a subheading [0], [1], [2] for each joint
Whenever you add an influence to a skinCluster, it connects the worldMatrix[0] attr. of the joint to the matrix[n] attr. of the skinCluster. A 'bindPreMatrix[n]' value is also created, and this attr. holds the bind pose for the the subset of the mesh that is influenced by joint/influence n.