A system and method for identifying a pointing organ or a pointing device in a field of imaging of a 3-D imaging system and for calculating a line of pointing relative to this organ or device are disclosed. The method and system may be used to enable a user to communicate with computer programs, such as computer games, 3-D design programs and the like. The method and system may further employ a trigger-like mechanism to identify a movement of a user that may be interpreted as trigger activation.
