1. A method for steering a laser beam of an active optical triangulation-based three-dimensional sensor by information extracted from an intensity image of a scene previewed by a video camera through laser beam deflection, comprising the steps of: generating an equation of a nominal laser spot path, at a datum plane; generating an equation of a desired path; generating an equation of a laser plane; generating coordinates of a laser point source; projecting all said coordinates onto a global three-space coordinate system; locating intersections of said spot path and said desired path with the said laser plane; computing a subtended angle of said intersections on said laser plane when viewed from a laser source point; and deflecting the laser beam through said computed subtended angle.