Real-time shading with filtered importance sampling

Jaroslav Křivánek Mark Colbert
Computer Graphics Forum (Proceedings of EGSR 2008) 27(4):1147-1154, 2008
Correct perception of materials requires complex, natural illumination [Fleming et al. 2003]. Thus for material or lighting design applications, realistic, interactive rendering of objects with arbitrary materials under natural illumination is essential. We present a simple and efficient technique for real-time, image-based lighting of objects with spatially-varying, glossy materials. The key to our algorithm is combining BRDF-proportional importance sampling with environment map filtering to attain computationally efficient rendering amenable to the GPU.