Global Illumination Rendering

Abstract

The ultimate objective of image synthesis or rendering is to provide the user with the illusion of watching real objects on the computer screen. The image on the computer screen consists of constant color small rectangles, called pixels. The color of pixels is generated from an internal model that is called the virtual world or the scene. To provide the illusion of watching the real world, the color sensation of an observer looking at the artificial image generated by the graphics display must be approximately equivalent to the color perception which would be obtained in the real world. The color perception of humans depends on the power spectrum of the light arriving at the eye from different viewing directions, i.e. on the number of photons of different frequencies. If we were able to get the computer display to emit photons of the same number and frequency as the virtual world, then the eye would not be able to distinguish the displayed image from the real world.