Reflective Shadow Map Clustering for Real-Time Global Illumination

Abstract

We present a method for real-time clustering of VPLs obtained from Reflective Shadow Maps (RSM). The clusters are treated as area light sources and used to approximate indirect illumination. The spatial extent of a cluster is used to deduce the shape and size of the respective area light source. Our method is fully GPU-based and avoids flickering by temporally coherent reinitialization of the clustering. It also incorporates importance sampling for view-dependent clustering. We show visually indistinguishable results of indirect illumination with only a fraction of secondary light sources.