Improved Monte Carlo form factor integration

Form factors are used in radiosity image synthesis to describe the fraction of diffusely reflected light leaving one surface and reaching another. The y incorporate fundamental geometric properties of interacting surfaces used for light transfer computation. Many numerical applications such as realis tic image synthesis require accurate and simple formula for the form factor s from small oriented differential areas (treated as a point with a normal) to different geometrical objects; a disk was used in this paper. The exact analytic solution for the general point-to-disk form factor integral is us ed to develop more accurate numerical techniques for form factor integratio n for surfaces commonly in use. The improvements are illustrated with reali stic image synthesis. (C) 1999 Elsevier Science Ltd. All rights reserved.