A Theoretical Framework for Physically Based Rendering
Eric P. Lafortune, Yves Willems · Computer Graphics Forum · 1994
Abstract In this paper we introduce the concept of the global reflection distribution function which allows concise formulation of the global illumination problem. Unlike previous formulations it is not geared towards any specific algorithm. As an example of its versatility we derive a Monte Carlo rendering algorithm that seamlessly integrates the ideas of shooting and gathering power to create photorealistic images.