17.3 Conclusion

The idea for pbrt was born in October 1999. Over the next five years, it evolved from a system designed only to support the students taking Stanford’s CS348b course to a robust, feature-rich, extensible rendering system. Since its inception, we have learned a great deal about what it takes to build a rendering system that doesn’t just make pretty pictures but is one that other people enjoy using and modifying as well. What has been most difficult, however, was designing a large piece of software that others might enjoy reading. This has been a far more challenging (and rewarding) task than implementing any of the rendering algorithms themselves.

After its first publication, the book enjoyed widespread adoption in advanced graphics courses worldwide, which we found very gratifying. We were unprepared, however, for the impact that pbrt has had on rendering research. Writing a ray tracer from scratch is a formidable task (as so many students in undergraduate graphics courses can attest), and creating a robust physically based renderer is much harder still. We are proud that pbrt has lowered the barrier to entry for aspiring researchers in rendering, making it easier for researchers to experiment with and demonstrate the value of new ideas in rendering. We continue to be delighted to see papers in SIGGRAPH, the Eurographics Rendering Symposium, High Performance Graphics, and other graphics research venues that either build on pbrt to achieve their goals, or compare their images to pbrt as “ground truth.”

More recently, we have been delighted again to see the rapid adoption of physically based approaches in practice for offline rendering and, recently as of this writing, games and interactive applications. Though we are admittedly unusual folk, it’s a particular delight to see incredible graphics on a screen and marvel at the billions of pseudo-random (or quasi-random) samples, billions of rays traced, and the complex mathematics that went into each image passing by.

We would like to sincerely thank everyone who has built upon this work for their own research, to build a new curriculum, to create amazing movies or games, or just to learn more about rendering. We hope that this new edition continues to serve the graphics community in the same way that its predecessors were able to.