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.org * 00021 ***************************************************************************/ 00022 00023 #ifndef LUX_IRREGULARSPD_H 00024 #define LUX_IRREGULARSPD_H 00025 // irregular.h* 00026 #include "lux.h" 00027 #include "color.h" 00028 #include "spectrum.h" 00029 #include "regular.h" 00030 00031 namespace lux 00032 { 00033 // only use spline for regular data 00034 enum SPDResamplingMethod { Linear, Spline }; 00035 00036 // Irregularly sampled SPD 00037 // Resampled to a fixed resolution (at construction) 00038 // using cubic spline interpolation 00039 class IrregularSPD : public SPD { 00040 public: 00041 00042 IrregularSPD() : SPD() {} 00043 00044 // creates an irregularly sampled SPD 00045 // may "truncate" the edges to fit the new resolution 00046 // wavelengths array containing the wavelength of each sample 00047 // samples array of sample values at the given wavelengths 00048 // n number of samples 00049 // resolution resampling resolution (in nm) 00050 IrregularSPD(const float* const wavelengths, const float* const samples, 00051 int n, float resolution = 5, SPDResamplingMethod resamplignMethod = Linear); 00052 00053 virtual ~IrregularSPD() {} 00054 00055 protected: 00056 void init(float lMin, float lMax, const float* const s, int n); 00057 00058 private: 00059 // computes data for natural spline interpolation 00060 // from Numerical Recipes in C 00061 void calc_spline_data(const float* const wavelengths, 00062 const float* const amplitudes, int n, float *spline_data); 00063 }; 00064 00065 }//namespace lux 00066 00067 #endif // LUX_IRREGULARSPD_H