Walt Disney Animation Studios Launches Open Source BRDF Explorer

Innovative and Versatile New Toolset Unveiled at SIGGRAPH
Takes Viewing BRDFs to New Levels of Accuracy and Efficiency

(August 8, 2012) Walt Disney Animation Studios (WDAS) is making its breakthrough BRDF Explorer available to the industry through a new open source site (github.com/wdas/brdf), it was announced August 7, 2012, at SIGGRAPH in Los Angeles by Brent Burley, the project’s principal engineer from WDAS software group. Burley, who gave a presentation at Tuesday’s conference on Disney’s proprietary approach to creating physically-based BRDFs (Bidirectional Reflectance Distribution Function, the mathematical description of how a surface reflects light), created the BRDF Explorer with his Disney colleagues Greg Nichols and Jared Johnson. He is a key player on the software team managed by Dan Candela, director of technology for WDAS.

Disney’s BRDF Explorer is an advanced physically-based shading and rendering toolset that evaluates BRDFs (a four-dimensional function that defines how light is reflected at an opaque surface) and how they compare to real life. It is capable of exploring the MERL 100 (Mitsubishi’s set of empirically measured data) and MIT CSAIL data sets, along with programmatic BRDF functions that can be defined by the user.

Said Burley, “We developed the BRDF Explorer to gain an intuition about the large number of BRDF models that have been developed over the years, to understand how well they fit real-world materials, and more importantly, see where they fall short. During this process, we discovered new ways to view the BRDF data more intuitively and holistically, and gained insights that allowed us to develop a robust new model. Somewhat surprisingly, our artists have also found this to be a very useful tool for crafting materials. We are happy to contribute this back to the graphics community and are excited to see what new BRDF innovations this tool will inspire.”

Peter Shirley, renowned principal research scientist at NVIDIA Research and adjunct professor for the School of Computing at University of Utah, added, “I have been doing research related to BRDFs for over 20 years, and yet I immediately learned new basic things from the output of this viewer. Often the key to scientific insight is getting the right picture, and this viewer accomplishes exactly that. It will become a staple in my own work.”

Naty Hoffman, vice president of technology at 2K and a pioneer in advancing realistic graphics in games and film, said, “The Disney BRDF Explorer is an excellent tool for analyzing, researching, developing and tuning BRDFs. I am sure that it will prove immensely useful for improving CG realism in film and games, as well as helping advance research in this important area.”

-- Posted August 8, 2012