PBRT
|
00001 00002 /* 00003 pbrt source code Copyright(c) 1998-2012 Matt Pharr and Greg Humphreys. 00004 00005 This file is part of pbrt. 00006 00007 Redistribution and use in source and binary forms, with or without 00008 modification, are permitted provided that the following conditions are 00009 met: 00010 00011 - Redistributions of source code must retain the above copyright 00012 notice, this list of conditions and the following disclaimer. 00013 00014 - Redistributions in binary form must reproduce the above copyright 00015 notice, this list of conditions and the following disclaimer in the 00016 documentation and/or other materials provided with the distribution. 00017 00018 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 00019 IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 00020 TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 00021 PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 00022 HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 00023 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 00024 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 00025 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 00026 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 00027 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 00028 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00029 00030 */ 00031 00032 #if defined(_MSC_VER) 00033 #pragma once 00034 #endif 00035 00036 #ifndef PBRT_TEXTURES_MARBLE_H 00037 #define PBRT_TEXTURES_MARBLE_H 00038 00039 // textures/marble.h* 00040 #include "pbrt.h" 00041 #include "texture.h" 00042 #include "paramset.h" 00043 00044 // MarbleTexture Declarations 00045 class MarbleTexture : public Texture<Spectrum> { 00046 public: 00047 // MarbleTexture Public Methods 00048 ~MarbleTexture() { 00049 delete mapping; 00050 } 00051 MarbleTexture(int oct, float roughness, float sc, float var, 00052 TextureMapping3D *map) 00053 : octaves(oct), omega(roughness), scale(sc), variation(var), 00054 mapping(map) { } 00055 Spectrum Evaluate(const DifferentialGeometry &dg) const { 00056 Vector dpdx, dpdy; 00057 Point P = mapping->Map(dg, &dpdx, &dpdy); 00058 P *= scale; 00059 float marble = P.y + variation * 00060 FBm(P, scale * dpdx, scale * dpdy, omega, octaves); 00061 float t = .5f + .5f * sinf(marble); 00062 // Evaluate marble spline at _t_ 00063 static float c[][3] = { { .58f, .58f, .6f }, { .58f, .58f, .6f }, { .58f, .58f, .6f }, 00064 { .5f, .5f, .5f }, { .6f, .59f, .58f }, { .58f, .58f, .6f }, 00065 { .58f, .58f, .6f }, {.2f, .2f, .33f }, { .58f, .58f, .6f }, }; 00066 #define NC sizeof(c) / sizeof(c[0]) 00067 #define NSEG (NC-3) 00068 int first = Floor2Int(t * NSEG); 00069 t = (t * NSEG - first); 00070 Spectrum c0 = Spectrum::FromRGB(c[first]); 00071 Spectrum c1 = Spectrum::FromRGB(c[first+1]); 00072 Spectrum c2 = Spectrum::FromRGB(c[first+2]); 00073 Spectrum c3 = Spectrum::FromRGB(c[first+3]); 00074 // Bezier spline evaluated with de Castilejau's algorithm 00075 Spectrum s0 = (1.f - t) * c0 + t * c1; 00076 Spectrum s1 = (1.f - t) * c1 + t * c2; 00077 Spectrum s2 = (1.f - t) * c2 + t * c3; 00078 s0 = (1.f - t) * s0 + t * s1; 00079 s1 = (1.f - t) * s1 + t * s2; 00080 // Extra scale of 1.5 to increase variation among colors 00081 return 1.5f * ((1.f - t) * s0 + t * s1); 00082 } 00083 private: 00084 // MarbleTexture Private Data 00085 int octaves; 00086 float omega, scale, variation; 00087 TextureMapping3D *mapping; 00088 }; 00089 00090 00091 Texture<float> *CreateMarbleFloatTexture(const Transform &tex2world, 00092 const TextureParams &tp); 00093 MarbleTexture *CreateMarbleSpectrumTexture(const Transform &tex2world, 00094 const TextureParams &tp); 00095 00096 #endif // PBRT_TEXTURES_MARBLE_H