Payware

Among the first programs meant to provide head tracking on personal computers, if not the first, one finds Cam2Pan. This program is basically a mouse emulator and this trait, coupled with the fact that in some contemporaneous flightsims it was possible to look around by moving the mouse, yielded the first head tracking system on personal computers.

  ↵This program, instead of using emitting diodes or reflective material as head tracking points, uses a paper model of predefined shape in order to provide for head tracking with six degrees of freedom, and therefore a webcam is the only prerequisite necessary to achieve head tracking with Cachya. The author of this website didn't check personally how strenuous for the CPU this approach to head ...