Progressive point-light-based global illumination

Abstract

We present a physically-based progressive global illumination system that is capable of simulating complex lighting situations robustly by efficiently using both light and eye paths. Specifically, we combine three distinct algorithms: point-light-based illumination which produces low-noise approximations for diffuse inter-reflections, specular gathering for glossy and singular effects, and a caustic histogram method for the remaining light paths. The combined system efficiently renders low-noise production quality images with indirect illumination from arbitrary light sources including inter-reflections from caustics and allows for simulating depth of field and dispersion effects. Our system computes progressive approximations by continuously refining the solution using a constant memory footprint without the need of pre-computations or optimizing parameters beforehand.