This book is noticeable, not only for its subject, but also for the way it is written. The authors decided to program a ray tracer following Knuth’s ideas about literate programming [1], which interleaves source code with text describing the code. This book is, in fact, a long literate program called pbrt, a photo-realistic, physically based ray-tracer written in C++.

Each chapter of the book describes a feature of pbrt, starting with a short description of the theory and following with the implementation. The source code is presented gradually, and is explained extensively with text and pictures. Each time a method or a variable is defined, there is a list of pages where it will be used. Conversely, when a method or a variable is used, there is a number indicating the page where it was first defined. At the end of each chapter, there is a list of exercises related to the material just covered.

Chapter 1 describes the overall architecture of pbrt. The rest of the book is divided into four parts. The first part defines the geometric functionality of the system, covering transforms, basic shapes, intersection test algorithms, and acceleration techniques. Part 2 covers the image generation process, with chapter 5 discussing color and radiometry theory, and chapter 6 presenting different implementations of a virtual camera. Sampling and anti-aliasing techniques are covered in chapter 7, and the general image pipeline is explained in chapter 8. Part 3 addresses the scattering of light, including the implementation of different physically based reflection models (chapter 9), materials (chapter 10), texture mapping (chapter 11), participating media (chapter 12), and light source models (chapter 13). The last part presents Monte Carlo integration estimation techniques (chapters 14 and 15) and their application to the light transport equation (chapters 16 and 17). The final chapter presents a summary, and discusses several possible extensions to pbrt, like parallel rendering and subsurface scattering.

There are six appendices and an extensive list of references. The appendices explain the implementation of generic utilities like mathematical functions, a memory management library, and image management routines; describe the scene description language; and provide lists with the page numbers where each class, method, and variable was first defined, and where it was used.

The book comes with a CD, and has a companion Web site. On the CD, readers will find source code; instructions on how to compile it under Windows and Unix; instructions on how to install the precompiled binaries for Windows, OS X, and Linux; some example images; and scene files. The Web site contains a list of bugs, updates to the source code, and additional scene files.

The book does not cover every possible rendering method; instead, the authors have concentrated on a few good and modern techniques. For omitted techniques, like radiosity, the provided list of references points to the appropriate literature.

Overall, this is an impressive book. It can be used not only as a textbook in a graduate or higher-level rendering course, but by any person interested in programming a photo-realistic ray tracer.