Radiosity Calculations for Rotational Surfaces

Helmut Mastal, Robert F. Tobler, Werner Purgathofer
Institute of Computer Graphics, Vienna University of Technology,
A-1040 Karlsplatz 13/186/2


Rotational Surfaces are very important for photorealistic representations of plants and other natural phenomena. In this paper radiosity calculations for rotational surfaces are presented that handle surfaces as whole objects rather than approximating them by large numbers of plane patches. Mathematical expressions are given for the radiance of cylinders, cones and spheres that are ideal Lambertian reflectors.
Although there exists no complete radiosity algorithm which uses the formulae for cylinders, cones and spheres at the moment, it can be estimated that the number of objects of a global illumination scene as well as the number of interactions could be reduced dramatically. Therefore it should be possible to render more complex scenes with plants, like forests, in reasonable time.


radiosity, rotational surfaces, natural phenomena