Cal3D is a skeletal based 3D character animation library written
in C++ in a platform-/graphic API-independent way. Originally
designed to be used in a 3D client for Worldforge, it evolved
into a stand-alone product which can be used in many different
kinds of projects. It supports combining animations and actions
through a 'mixer' interface, and work is currently underway to
integrate morph targets (interpolating between one mesh and
another, using the same vertex sequence) easily into the system.