This book presents techniques to render photo-realistic images by programming the Graphics Processing Unit (GPU). We discuss effects such as mirror reflections, refractions, caustics, diffuse or glossy indirect illumination, radiosity, single or multiple scattering in participating media, tone reproduction, glow, and depth of field. The book targets game developers, graphics programmers, and also students with some basic understanding of computer graphics algorithms, rendering APIs like Direct3D or OpenGL, and shader programming. In order to make the book self-contained, the most important concepts of local illumination and global illumination rendering, graphics hardware, and Direct3D/HLSL programming are reviewed in the first chapters. After these introductory chapters we warm up with simple methods including shadow and environment mapping, then we move on toward advanced concepts aiming at global illumination rendering. Since it would have been impossible to give a rigorous review of all approaches proposed in this field, we go into the details of just a few methods solving each particular global illumination effect. However, a short discussion of the state of the art and links to the bibliography are also provided to refer the interested reader to techniques that are not detailed in this book. The implementation of the selected methods is also presented in HLSL, and we discuss their observed performance, merits, and disadvantages. In the last chapter, we also review how these techniques can be integrated in an advanced game engine and present case studies of their exploitation in games. Having gone through this book, the reader will have an overview of the state of the art, will be able to apply and improve these techniques, and most importantly, will be capable of developing brand new GPU algorithms.

本书介绍了通过对图形处理单元（GPU）进行编程来渲染照片般逼真的图像的技术。我们讨论了镜面反射、折射、苛化、漫反射或光泽间接照明、辐射度、参与媒体中的单一或多重散射、色调再现、发光和景深等效果。本书的目标读者是游戏开发者、图形程序员，以及对计算机图形算法、渲染API（如Direct3D或OpenGL）和着色器编程有一些基本了解的学生。为了使本书自成体系，在第一章中回顾了局部光照和全局光照渲染、图形硬件和Direct3D/HLSL编程等最重要的概念。在这些介绍性的章节之后，我们用简单的方法进行热身，包括阴影和环境贴图，然后我们转向以全局照明渲染为目标的高级概念。由于不可能对这一领域提出的所有方法进行严格的审查，我们只对解决每个特定的全局照明效果的少数方法进行了详细的介绍。然而，我们也提供了对技术现状的简短讨论和参考书目的链接，以便让感兴趣的读者了解本书中没有详细介绍的技术。所选方法的实现也在HLSL中呈现，我们讨论了它们的观察性能、优点和缺点。在最后一章，我们还回顾了如何将这些技术整合到高级游戏引擎中，并介绍了在游戏中利用这些技术的案例研究。通过本书的学习，读者将对该技术的现状有一个大致的了解，能够应用和改进这些技术，最重要的是，能够开发全新的GPU算法。