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 // lowdiscrepancypx.cpp* 00024 #include "lowdiscrepancypx.h" 00025 #include "error.h" 00026 00027 using namespace lux; 00028 00029 // LowdiscrepancyPixelSampler Method Definitions 00030 LowdiscrepancyPixelSampler::LowdiscrepancyPixelSampler(int xstart, int xend, 00031 int ystart, int yend) { 00032 xPixelStart = xstart; 00033 yPixelStart = ystart; 00034 xPixelEnd = xend; 00035 yPixelEnd = yend; 00036 xSeed = lux::random::uintValueP(); 00037 ySeed = lux::random::uintValueP(); 00038 00039 TotalPx = (xend - xstart) * (yend - ystart); 00040 pixelCounter = 0; 00041 } 00042 00043 u_int LowdiscrepancyPixelSampler::GetTotalPixels() { 00044 #if defined(WIN32) && !defined(__CYGWIN__) 00045 #undef max // before the use of vaR.max function 00046 #endif 00047 return std::numeric_limits<unsigned int>::max(); 00048 } 00049 00050 bool LowdiscrepancyPixelSampler::GetNextPixel(int &xPos, int &yPos, u_int *use_pos) { 00051 bool hasMorePixel = true; 00052 if(pixelCounter == TotalPx) { 00053 pixelCounter = 0; 00054 hasMorePixel = false; 00055 } 00056 00057 pixelCounter++; 00058 00059 xPos = xPixelStart + Floor2Int( VanDerCorput( *use_pos, xSeed ) * (xPixelEnd - xPixelStart) ); 00060 yPos = yPixelStart + Floor2Int( Sobol2( *use_pos, ySeed ) * (yPixelEnd - yPixelStart) ); 00061 00062 return hasMorePixel; 00063 }