Real-time Caustics and Dispersion on Arbitrary Surfaces in GPU-Accelerated Ray Tracing

Abstract

Caustics, the envelope of light rays reflected or refracted by a curved surface or its projection, are an important phenomenon for photorealistic rendering. Previous methods either did not achieve real-time performance, did not include chromatic dispersion, or did not allow projection of light envelopes onto complex surfaces. In this paper we present algorithms for rendering caustics at interactive frame rates for arbitrary surfaces. Our solution uses GPU-acceleration and a combination of geometry buffers, light buffers, and coordinate transformations in order to utilise GPU capabilities. We show that our technique achieves realistic results for complex objects using consumer-level graphics cards.