The sort-first rendering architecture for high-performance graphics

Interactive graphics applications have long been challenging graphics system designers by demanding machines that can provide ever increasing polygon rendering performance. Another trend in interactive graphics is the growing use of display devices with pixel counts well beyond what is usually considered “high-resolution.” If we examine the architectural space of high-performance rendering systems, we discover only one architectural class that promises to deliver high polygon performance with very-high-resolution displays and do so in an efficient manner. It is known as “sort-first.” We investigate the sort-first architecture, starting with a comparison to its architectural class mates (sort-middle and sort-last). We find that sort-first has an inherent ability to take advantage of the frame-to-frame coherence found in interactive applications. We examine this ability through simulation with a set of test applications and show how it reduces sort-first's communication needs and therefore its parallel overhead. We also explore the issue of load-balancing with sort-first and introduce a new adaptive algorithm to solve this problem. Additional simulations demonstrate the effectiveness of this algorithm. Finally, we touch on a variety of issues that must be resolved in order to fulfill sort-first's ultimate promise: millions of polygons for zillions of pixels.