NITE 1.5.1 - API Reference
There are many objects that get the hand points (see XnVHandPointContext), and perform some action. This action is to understand the stream of points as a coherent movement. These objects are all subclasses of XnVMessageListener. Objects that send hand points (or, indeed, any other data) are subclasses of XnVMessageGenerator. There are controls that both receive data and send data, either filtering the data or altering it. Those are subclasses of either XnVFilter or XnVPointFilter, themselves subclasses of both Generator and Listener.