HARDWARE-ACCELERATED PARALLEL-SPLIT SHADOW MAPS

Abstract

Shadow mapping is well known for its generality and efficiency, thus it has been extensively employed for real-time shadow rendering in diverse applications. However, it suffers from inherent aliasing problem due to its image-based nature. In this paper, we present the parallel-split shadow maps scheme which produces high-quality shadows especially in large-scale and complex scenes. Our scheme splits the view frustum into parts using planes parallel to the view plane, and then generates a shadow map for each part. A fast and robust splitting strategy based on the analysis of shadow-map aliasing is proposed, which results in a moderate aliasing distribution over the depth range. Hardware-accelerated processing is developed to eliminate extra rendering passes which surpass that of standard shadow mapping when synthesizing scene-shadows.