Accelerated shadow testing method for three dimensional graphics render system

摘要

Shadow testing of a two dimensional projection of a three dimensional scene is accelerated by superimposing the projection with a plurality of scan areas SA1-SA7, then examining points P1, P2, and edges E1-E3 of objects 01, 02, falling within each scan area. Points are identified as potentially shadowed points PS02 if bracketed by edges of any object, and the bracketing object is identified as a potential shadower of the potentially shaded points. Potential shadowers and potentially shadowed points undergo a series of tests to rapidly determine which, if any, of the potential shadowers are actual shadowers of each potentially shadowed point.