10. The method of claim 5 , wherein: said user actor comprises at least one of a hand, a finger, and a stylus.
5. A method, comprising: establishing in a processor an imaging field of view; defining an input region in said processor within said field of view; defining a user actor input in said processor; defining in said processor a command; associating said command with said input in said processor; outputting said imaging field of view to a display; outputting to said display a virtual object occupying at least a portion of said region; obtaining at least one image of at least a portion of said field of view with said input in said region; identifying in said processor a plurality of salient features of said user actor comprising a structure of said user actor from said input delivered by said user actor in said region in said image, said structure comprising a geometry of said user actor; executing said command in said processor in response to said input; defining a model of said user actor in said processor from said salient features, said user actor model comprising said geometry thereof; retaining said user actor model; and using said user actor model to identify said user actor in said processor in subsequent images.