Institute for Data Analysis and Visualization

We present a novel implementation of adaptive shadow maps (ASMs) that performs all shadow lookups and scene analysis on the GPU, enabling interactive rendering with ASMs while moving both the light and camera. Adaptive shadow maps offer a rigorous solution to projective and perspective shadow map aliasing while maintaining the simplicity of a purely image-based technique. The complexity of the ASM data structure, however, has prevented full GPU-based implementations until now. Our approach uses an entirely GPU-based data structure and a blend of graphics and GPU stream programming. We support shadow map effective resolutions up to 131,072 x 131,072 and, unlike previous implementations, provide smooth transitions between resolution levels by trilinearly filtering (mipmapping) the shadow lookups.