00001 /*************************************************************************** 00002 * Copyright (C) 1998-2009 by authors (see AUTHORS.txt ) * 00003 * * 00004 * This file is part of LuxRender. * 00005 * * 00006 * Lux Renderer is free software; you can redistribute it and/or modify * 00007 * it under the terms of the GNU General Public License as published by * 00008 * the Free Software Foundation; either version 3 of the License, or * 00009 * (at your option) any later version. * 00010 * * 00011 * Lux Renderer is distributed in the hope that it will be useful, * 00012 * but WITHOUT ANY WARRANTY; without even the implied warranty of * 00013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * 00014 * GNU General Public License for more details. * 00015 * * 00016 * You should have received a copy of the GNU General Public License * 00017 * along with this program. If not, see <http://www.gnu.org/licenses/>. * 00018 * * 00019 * This project is based on PBRT ; see http://www.pbrt.org * 00020 * Lux Renderer website : http://www.luxrender.net * 00021 ***************************************************************************/ 00022 00023 #ifndef LUX_WARDISOTROPIC_H 00024 #define LUX_WARDISOTROPIC_H 00025 // wardisotropic.h* 00026 #include "lux.h" 00027 #include "microfacetdistribution.h" 00028 00029 namespace lux 00030 { 00031 00032 // Kelemen and Szirmay-Kalos / Microfacet Based BRDF Model, Eurographics 2001 00033 class WardIsotropic : public MicrofacetDistribution { 00034 public: 00035 00036 WardIsotropic (float rms); 00037 virtual ~WardIsotropic() { } 00038 00039 // WardIsotropic Public Methods 00040 virtual float D (const Vector &wh) const; 00041 virtual void Sample_f (const Vector &wi, Vector *sampled_f, float u1, float u2, float *pdf) const; 00042 virtual float Pdf (const Vector &wi, const Vector &wo) const; 00043 00044 private: 00045 00046 float r; 00047 }; 00048 00049 }//namespace lux 00050 00051 #endif // LUX_WARDISOTROPIC_H 00052