1. A computer-implemented process for using a quadrangular panel and a pointer overlaying the panel to control a remote display, comprising using a computer to perform the following process actions: inputting an image of a quadrangular panel and a pointer; locating the position of the quadrangular panel in said image; computing a projective mapping between the coordinates of said image and the coordinates of at least one remote display; locating a tip of the pointer in said image; and determining coordinates on the remote display corresponding to the location of the tip of the pointer on the quadrangular panel as depicted in the image using said projective mapping.