Pharr Matt - Physically Based Rendering

THIRD EDITION

Matt Pharr

Wenzel Jakob

Greg Humphreys

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ISBN: 978-0-12-800645-0

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To Deirdre , who even let me bring the manuscript on our honeymoon.

M. P.

To Olesya , who thought it was cute that my favorite book is a computer program.

W. J.

To Isabel and Leila , the two most extraordinary people Ive ever met. May your pixels never be little squares.

G. H.

Matt Pharr is a Software Engineer at Google. He previously co-founded Neoptica, which was acquired by Intel, and co-founded Exluna, which was acquired by NVIDIA. He has a B.S. degree from Yale and a Ph.D. from the Stanford Graphics Lab, where he worked under the supervision of Pat Hanrahan.

Wenzel Jakob is an assistant professor in the School of Computer and Communication Sciences at cole Polytechnique Fdrale de Lausanne (EPFL). His research interests revolve around material appearance modeling, rendering algorithms, and the high-dimensional geometry of light paths. Wenzel obtained his Ph.D. at Cornell University under the supervision of Steve Marschner, after which he joined ETH Zrich for post-doctoral studies under the supervision of Olga Sorkine Hornung. Wenzel is also the lead developer of the Mitsuba renderer, a research-oriented rendering system.

Greg Humphreys is Director of Engineering at FanDuel, having previously worked on the Chrome graphics team at Google and the OptiX GPU ray-tracing engine at NVIDIA. Before that, he was a professor of Computer Science at the University of Virginia, where he conducted research in both high-performance and physically based computer graphics, as well as computer architecture and visualization. Greg has a B.S.E. degree from Princeton and a Ph.D. in Computer Science from Stanford under the supervision of Pat Hanrahan. When hes not tracing rays, Greg can usually be found playing tournament bridge.

[Just as] other information should be available to those who want to learn and understand, program source code is the only means for programmers to learn the art from their predecessors. It would be unthinkable for playwrights not to allow other playwrights to read their plays [or to allow them] at theater performances where they would be barred even from taking notes. Likewise, any good author is well read, as every child who learns to write will read hundreds of times more than it writes. Programmers, however, are expected to invent the alphabet and learn to write long novels all on their own. Programming cannot grow and learn unless the next generation of programmers has access to the knowledge and information gathered by other programmers before them. Erik Naggum

Rendering is a fundamental component of computer graphics. At the highest level of abstraction, rendering is the process of converting a description of a three-dimensional scene into an image. Algorithms for animation, geometric modeling, texturing, and other areas of computer graphics all must pass their results through some sort of rendering process so that they can be made visible in an image. Rendering has become ubiquitous; from movies to games and beyond, it has opened new frontiers for creative expression, entertainment, and visualization.

In the early years of the field, research in rendering focused on solving fundamental problems such as determining which objects are visible from a given viewpoint. As effective solutions to these problems have been found and as richer and more realistic scene descriptions have become available thanks to continued progress in other areas of graphics, modern rendering has grown to include ideas from a broad range of disciplines, including physics and astrophysics, astronomy, biology, psychology and the study of perception, and pure and applied mathematics. The interdisciplinary nature of rendering is one of the reasons that it is such a fascinating area of study.

This book presents a selection of modern rendering algorithms through the documented source code for a complete rendering system. Nearly all of the images in this book, including the one on the front cover, were rendered by this software. All of the algorithms that came together to generate these images are described in these pages. The system, pbrt , is written using a programming methodology called literate programming that mixes prose describing the system with the source code that implements it. We believe that the literate programming approach is a valuable way to introduce ideas in computer graphics and computer science in general. Often, some of the subtleties of an algorithm can be unclear or hidden until it is implemented, so seeing an actual implementation is a good way to acquire a solid understanding of that algorithms details. Indeed, we believe that deep understanding of a small number of algorithms in this manner provides a stronger base for further study of computer graphics than does superficial understanding of many.