00001 /*************************************************************************** 00002 * Copyright (C) 1998-2008 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_FRESNEL_H 00024 #define LUX_FRESNEL_H 00025 // fresnel.h* 00026 #include "lux.h" 00027 #include "spectrum.h" 00028 00029 namespace lux 00030 { 00031 00032 class Fresnel { 00033 public: 00034 // Fresnel Interface 00035 virtual ~Fresnel(); 00036 virtual SWCSpectrum Evaluate(float cosi) const = 0; 00037 }; 00038 00039 SWCSpectrum FrDiel(float cosi, float cost, 00040 const SWCSpectrum &etai, const SWCSpectrum &etat); 00041 SWCSpectrum FrCond(float cosi, const SWCSpectrum &n, const SWCSpectrum &k); 00042 SWCSpectrum FresnelApproxEta(const SWCSpectrum &intensity); 00043 SWCSpectrum FresnelApproxK(const SWCSpectrum &intensity); 00044 00045 }//namespace lux 00046 00047 #endif // LUX_FRESNEL_H 00048