Animation for Games: Animation and Skinning

Recap: In the last couple of lectures we introduced the principal elements of skeletal models and how to represent animations. Recall that a skeletal model consists of a collection of joints, which have been joined into a rooted tree structure. Recall that a pose is defined by rotating each of the joints in a specific way. Rotations are defined relative to a default pose, called the bind pose or reference pose. The mesh defining the character’s skin is defined relative to this pose. (Typically this is the character standing upright with arms outstretched to the sides.) Each node j of this tree is (either implicitly or explicitly) associated with a the following relevant transformations: