Efficient primitive traversal using adaptive linear edge function algorithms

摘要

Graphics performance is today an important part of a PC's performance statistics. Although scan conversion performance is now overshadowed by texture mapping ability, the choice of primitive traversal algorithm can still introduce a bottleneck in the rasterisation pipeline. After all, the primitive traversal engine generates the pixel fragments on which the remainder of the rasterisation pipeline will operate to produce a pixel colour. Poor primitive traversal performance will limit the potential of the entire graphics pipeline. In this paper we discuss the implementation of triangle traversal algorithms that use linear edge functions. Methods for increasing algorithm performance and the cost of cost of hardware implementation are examined. We show that traversal algorithm efficiency is very important for small primitives. This is very important as primitive size is reducing rapidly to increase the accuracy with which scenes can be modelled.