Sketchpad III a Computer Program for Drawing in Three Dimensions

An important area of investigation for the M.I.T. Computer-Aided Design Project is the development of a facility for three-dimensional shape description. The heavy dependence of mechanical design upon three-dimensional objects makes such a facility an indispensable part of the full system which is envisioned. This paper describes the unique features required for three-dimensional graphics. Although the Sketchpad III System described here shares many features and routines with the Sketchpad System described in the preceding paper by Sutherland, the extension of graphical techniques from two to three dimensions introduces many added requirements.