PBRT
/home/felix/UBC/projects/AdaptiveLightfieldSampling/pbrt_v2/src/textures/checkerboard.h
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_CHECKERBOARD_H
00037 #define PBRT_TEXTURES_CHECKERBOARD_H
00038 
00039 // textures/checkerboard.h*
00040 #include "pbrt.h"
00041 #include "texture.h"
00042 #include "paramset.h"
00043 #include "montecarlo.h"
00044 #include "shape.h"
00045 #include "parallel.h"
00046 #include "progressreporter.h"
00047 
00048 // CheckerboardTexture Declarations
00049 template <typename T> class Checkerboard2DTexture : public Texture<T> {
00050 public:
00051     // Checkerboard2DTexture Public Methods
00052     Checkerboard2DTexture(TextureMapping2D *m, Reference<Texture<T> > c1,
00053                           Reference<Texture<T> > c2, const string &aa)
00054         : mapping(m), tex1(c1), tex2(c2) {
00055         // Select antialiasing method for _Checkerboard2DTexture_
00056         if (aa == "none")             aaMethod = NONE;
00057         else if (aa == "closedform")  aaMethod = CLOSEDFORM;
00058         else {
00059             Warning("Antialiasing mode \"%s\" not understood by "
00060                     "Checkerboard2DTexture; using \"closedform\"", aa.c_str());
00061             aaMethod = CLOSEDFORM;
00062         }
00063     }
00064     ~Checkerboard2DTexture() {
00065         delete mapping;
00066     }
00067     T Evaluate(const DifferentialGeometry &dg) const {
00068         float s, t, dsdx, dtdx, dsdy, dtdy;
00069         mapping->Map(dg, &s, &t, &dsdx, &dtdx, &dsdy, &dtdy);
00070         if (aaMethod == NONE) {
00071             // Point sample _Checkerboard2DTexture_
00072             if ((Floor2Int(s) + Floor2Int(t)) % 2 == 0)
00073                 return tex1->Evaluate(dg);
00074             return tex2->Evaluate(dg);
00075         }
00076         else {
00077             // Compute closed-form box-filtered _Checkerboard2DTexture_ value
00078 
00079             // Evaluate single check if filter is entirely inside one of them
00080             float ds = max(fabsf(dsdx), fabsf(dsdy));
00081             float dt = max(fabsf(dtdx), fabsf(dtdy));
00082             float s0 = s - ds, s1 = s + ds;
00083             float t0 = t - dt, t1 = t + dt;
00084             if (Floor2Int(s0) == Floor2Int(s1) && Floor2Int(t0) == Floor2Int(t1)) {
00085                 // Point sample _Checkerboard2DTexture_
00086                 if ((Floor2Int(s) + Floor2Int(t)) % 2 == 0)
00087                     return tex1->Evaluate(dg);
00088                 return tex2->Evaluate(dg);
00089             }
00090 
00091             // Apply box filter to checkerboard region
00092 #define BUMPINT(x) \
00093                 (Floor2Int((x)/2) + \
00094                  2.f * max((x/2)-Floor2Int(x/2) - .5f, 0.f))
00095             float sint = (BUMPINT(s1) - BUMPINT(s0)) / (2.f * ds);
00096             float tint = (BUMPINT(t1) - BUMPINT(t0)) / (2.f * dt);
00097             float area2 = sint + tint - 2.f * sint * tint;
00098             if (ds > 1.f || dt > 1.f)
00099                 area2 = .5f;
00100             return (1.f - area2) * tex1->Evaluate(dg) +
00101                    area2         * tex2->Evaluate(dg);
00102         }
00103     }
00104 private:
00105     // Checkerboard2DTexture Private Data
00106     TextureMapping2D *mapping;
00107     Reference<Texture<T> > tex1, tex2;
00108     enum { NONE, CLOSEDFORM } aaMethod;
00109 };
00110 
00111 
00112 template <typename T> class Checkerboard3DTexture : public Texture<T> {
00113 public:
00114     // Checkerboard3DTexture Public Methods
00115     Checkerboard3DTexture(TextureMapping3D *m, Reference<Texture<T> > c1,
00116                           Reference<Texture<T> > c2)
00117         : mapping(m), tex1(c1), tex2(c2) {
00118     }
00119     ~Checkerboard3DTexture() {
00120         delete mapping;
00121     }
00122     T Evaluate(const DifferentialGeometry &dg) const {
00123         Vector dpdx, dpdy;
00124         Point p = mapping->Map(dg, &dpdx, &dpdy);
00125         if ((Floor2Int(p.x) + Floor2Int(p.y) + Floor2Int(p.z)) % 2 == 0)
00126             return tex1->Evaluate(dg);
00127         else
00128             return tex2->Evaluate(dg);
00129     }
00130 private:
00131     // Checkerboard3DTexture Private Data
00132     TextureMapping3D *mapping;
00133     Reference<Texture<T> > tex1, tex2;
00134 };
00135 
00136 
00137 Texture<float> *CreateCheckerboardFloatTexture(const Transform &tex2world,
00138         const TextureParams &tp);
00139 Texture<Spectrum> *CreateCheckerboardSpectrumTexture(const Transform &tex2world,
00140         const TextureParams &tp);
00141 
00142 #endif // PBRT_TEXTURES_CHECKERBOARD_H