The binary space partitioning (BSP) tree algorithm was developed by Fuchs, Kedem, and Naylor [7], based on work of Schumacker [8]. The BSP tree algorithm is an efficient method for calculating the visibility relationships among a static group of 3D polygons as seen from an arbitrary viewpoint. It trades off an initial time and space intensive preprocessing step against a linear display algorithm that is executed whenever a new viewing specification is desired. Thus, the algorithm is well suited for applications in which the viewpoint changes but the objects do not.