The Impact Factor Analysis on the Improved Cook-Torrance Bidirectional Reflectance Distribution Function of Rough Surfaces
The Cook-Torrance BRDF of the material is not energy balanced for the reflected radiance and the albedo converges to zero at grazing angles. This gap is filled by appropriate modifications of the Cook-Torrance BRDF model. The improved BRDF model is relevant with the surface roughness, the distribution of visible normal, the Fresnel factor and the geometrical attenuation factor. The model is applied to metallic surfaces with various values of root mean square and the geometrical attenuation factors as the incidence angle is increased. The improved model is analytic and suitable for Computer Graphics applications.
KeywordsBRDF model Geometrical attenuation factor Microsurface theory
This work was supported by the Department of Education Shaanxi Province, China, under Grant 2013JK1023, and Shaanxi STA International Cooperation and Exchanges Project (2017KW-011).
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