Abstract

Bump mapping is a normal-perturbation rendering technique for simulating lighting effects caused by patterned irregularities on otherwise locally smooth surfaces. By encoding such surface patterns in texture maps, texture-based bump mapping simulates a surface's irregular lighting appearance without modeling the patterns as true geometric perturbations to the surface. Bump mapping is advantageous because it can decouple a texture-based description of small-scale surface irregularities used for per-pixel lighting computations from the vertexbased description of large-scale object shape required for efficient transformation and rasterization. This paper describes a practical and robust bump-mapping technique suited for the capabilities of today's Graphics Processor Units (GPUs).