Ray Tracing from the Ground Up

Chapter 26

Global Illumination

Image courtesy of Steven Parker

Objectives

By the end of this chapter, you should:

• understand how path tracing works;
• know how to combine direct and indirect illumination in a path tracer;
• appreciate path tracing's abilities and limitations.

26.1 Light Transport

In previous chapters, we looked at direct illumination from a variety of light sources and at indirect illumination with perfect specular and glossy specular reflection. There are, however, many other ways that light can be transported in a scene. The general situation is reflection between surfaces with arbitrary BRDFs. An example is reflection between ...