ABSTRACT
Texturing is a ubiquitous technique used to enrich surface appearance with fine detail. While standard filtering approaches, such as mipmapping or summed area tables, are available for rendering diffuse reflectance textures at different levels of detail, no widely accepted filtering solution exists for multiresolution rendering of surfaces with fine specular normal maps. The current state of the art offers accurate filtering solutions for specular reflection at the cost of very high memory requirements and expensive 4D queries. We propose a novel normal map filtering solution for specular surfaces which supports data pre-filtering, and with an evaluation speed that is roughly independent of the filtering footprint size. Its memory usage and evaluation speed are significantly more favorable than for existing methods. Our solution is based on high-resolution binning in the half-vector domain, which allows us to quickly build a very memory efficient data structure.
Supplemental Material
Available for Download
- Luis E. Gamboa, Jean-Philippe Guertin, and Derek Nowrouzezahrai. 2018. Scalable Appearance Filtering for Complex Lighting Effects. ACM Trans. Graph. 37, 6, Article 277 (Dec. 2018), 13 pages. https://doi.org/10.1145/3272127.3275058Google ScholarDigital Library
- Homan Igehy. 1999. Tracing Ray Differentials. In Proceedings of SIGGRAPH ’99. ACM Press/Addison-Wesley Publishing Co., New York, NY, USA, 179–186. https://doi.org/10.1145/311535.311555Google ScholarDigital Library
- Bruce Walter, Stephen R. Marschner, Hongsong Li, and Kenneth E. Torrance. 2007. Microfacet Models for Refraction Through Rough Surfaces. In Proceedings of the 18th Eurographics Conference on Rendering Techniques (Grenoble, France) (EGSR’07). Eurographics Association, Aire-la-Ville, Switzerland, 195–206. https://doi.org/10.2312/EGWR/EGSR07/195-206Google ScholarDigital Library
- Ling-Qi Yan, Miloš Hašan, Steve Marschner, and Ravi Ramamoorthi. 2016. Position-Normal Distributions for Efficient Rendering of Specular Microstructure. ACM Transactions on Graphics (Proceedings of SIGGRAPH 2016) 35, 4(2016).Google Scholar
Recommendations
Rendering specular microgeometry with wave optics
Simulation of light reflection from specular surfaces is a core problem of computer graphics. Existing solutions either make the approximation of providing only a large-area average solution in terms of a fixed BRDF (ignoring spatial detail), or are ...
Position-normal distributions for efficient rendering of specular microstructure
Specular BRDF rendering traditionally approximates surface microstructure using a smooth normal distribution, but this ignores glinty effects, easily observable in the real world. While modeling the actual surface microstructure is possible, the ...
Rendering glints on high-resolution normal-mapped specular surfaces
Complex specular surfaces under sharp point lighting show a fascinating glinty appearance, but rendering it is an unsolved problem. Using Monte Carlo pixel sampling for this purpose is impractical: the energy is concentrated in tiny highlights that take ...
Comments