Ray Tracing Essentials Part 6: The Rendering Equation

Eric Haines explains the mathematical terms of the rendering equation and how sampling strategies improve ray tracing performance.

In Part 6: NVIDIA’s Eric Haines describes the ray tracing rendering equation. Arguably the most important equation in realistic computer graphics is The Rendering Equation. In this talk we show this equation and explain each term. Pure tracing will always eventually give the right answer, but the key word is “eventually.” By using better sampling strategies, shooting rays where they can do the most good, we can dramatically cut rendering times. Doing so lets us use path tracing for even interactive games, such as Quake II. Learn more here: news.developer.nvidia.com/ray-tracing-essentials-part-6-the-… You can watch the all of the videos in the series on this YouTube Playlist: youtube.com/playlist?list=PL5B692fm6--sgm8Uiava0IIvUojjFOCSR Ray tracing resources page: bit.ly/rtrtinfo Ray Tracing Gems: raytracinggems.com On May 12, Eric Haines will present a live webinar about the Ray Tracing Essentials series. There will be a presentation, live Q&A, plus a giveaway of an NVIDIA TITAN RTX GPU (For live attendees only.) Sign up here: info.nvidia.com/developer-ray-tracing-webinar-reg-page.html. Additional links: Much of this talk was drawn from Morgan McGuire’s “Path Tracing Review” slideset, morgan3d.github.io/advanced-ray-tracing-course/path-tracing-…, ; see it for a more in-depth exploration (and more eye-candy). The figures shown for multiple importance sampling are from the paper “Optimally Combining Sampling Techniques for Monte Carlo Rendering,”, dl.acm.org/doi/abs/10.1145/218380.218498, by Veach and Guibas, SIGGRAPH 95 (original website, graphics.stanford.edu/papers/combine/, ). The (now-free) book Physically Based Rendering, pbr-book.org/, has a good summary, pbr-book.org/3ed-2018/Monte_Carlo_Integration/Importance_Sam…, of this seminal work. The original ray-traced Quake II code is available as Q2VKPT, brechpunkt.de/q2vkpt/. The updated playable demo is downloadable here,nvidia.com/en-us/geforce/campaigns/quake-II-rtx/, with some explanation of improvements here, nvidia.com/en-us/geforce/news/quake-ii-rtx-v1-2-update.