A one-man operation called CamTrax Technologies has developed 3D input software called CamSpace that improves upon the system used by the Nintendo Wii:
CamTrax’s core technology is a pure software solution that allows nearly any ordinary PC webcam (95% are supported) to track up to four objects—even as small as 5mm—in real-time and with very high accuracy and reliability. (It works only on Windows). Locking and tracking (X, Y, and Z axes and angle) are all automatic. Yaron Tanne, founder & CEO of CamTrax Technologies, the company behind CamSpace, has been developing the technology practically single-handedly for three years in his apartment in Tel-Aviv.
Tanne claims that most of the algorithms used are in the public domain but have been enhanced. There are also completely new algorithms developed from scratch.
CamSpace requires an agent application to run locally in order to emulate a mouse, a keyboard, joystick, or other input device. Users can then program the emulation based on the game they want to control and the object(s) they want to control the game with. For example, one user could program a steering wheel for a racing game, where moving the wheel on the Z axis shifts the gears up and down. A different user can use two objects for the same game, programming the second object, say a coke bottle, to shift the gears.