Radiosity - Polygon Rendering & Ray Tracing Methods
Radiosity simulates the diffuse propagation of light begin at the light sources. Because global illumination is an extremely difficult problem and along with a standard ray tracing algorithm, which is an extremely time consuming task, like a vast number of rays have to be shot. For this purpose, the radiosity method was invented. The basic idea of the method is to store illumination values upon the surfaces of the objects, like the light is propagated begin on the light sources.
Deterministic radiosity algorithms were utilized for radiosity for fairly some instant, although they are too slow for computing global illumination for extremely complicate scenes. For this purpose, stochastic methods were invented, which simulate the photon propagation via a Monte Carlo type algorithm.