Polyline and triangle strip data management techniques for enhancing

Abstract

A geometry accelerator for a computer graphics system performs transformations on vertex data representative of graphics primitives, decomposes quadrilaterals into triangles, and performs lighting, clipping and plane equation calculations for each primitive. The geometry accelerator incorporates a memory mapping technique that achieves high efficiency transfer of vertex information from the host computer to the geometry accelerator. A double buffered vertex RAM with granularity permits the quantity of data transferred to the geometry accelerator to be reduced. The transformation and decomposition engines of the geometry accelerator employ data management techniques in which calculations for shared vertices and shared edges of primitives are performed only once.