Generic BRDF Sampling - A Sampling Method for Global Illumination
نویسندگان
چکیده
This paper introduces a new BRDF sampling method with reduced variance, which is based on a hierarchical adaptive parameterless PDF. This PDF is based also on rejection sampling with a bounded average number of trials, even in regions where the BRDF does exhibit high variations. Our algorithm works in an appropiate way with both physical and analytical reflectance models. Reflected directions are sampled by using importance sampling of the BRDF times the cosine term. This fact improves computation of reflected radiance when Monte-Carlo integration is used in Global Illumination. Test images have been obtained by using a MonteCarlo rendering system, and they show reduced variance as compared with those obtained by other known techniques.
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تاریخ انتشار 2008