1 | /* -*- mode: c++; c-basic-offset: 4; indent-tabs-mode: nil -*- */ |
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2 | /* |
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3 | * ---------------------------------------------------------------------- |
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4 | * VolumeRenderer.cpp : VolumeRenderer class for volume visualization |
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5 | * |
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6 | * ====================================================================== |
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7 | * AUTHOR: Wei Qiao <qiaow@purdue.edu> |
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8 | * Purdue Rendering and Perceptualization Lab (PURPL) |
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9 | * |
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10 | * Copyright (c) 2004-2013 HUBzero Foundation, LLC |
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11 | * |
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12 | * See the file "license.terms" for information on usage and |
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13 | * redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES. |
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14 | * ====================================================================== |
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15 | */ |
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16 | #include <stdlib.h> |
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17 | #include <float.h> |
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18 | |
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19 | #include <vector> |
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20 | |
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21 | #include <GL/glew.h> |
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22 | |
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23 | #include <vrmath/Vector3f.h> |
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24 | #include <vrmath/Matrix4x4d.h> |
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25 | |
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26 | #include "nanovis.h" |
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27 | #include "VolumeRenderer.h" |
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28 | #include "Plane.h" |
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29 | #include "ConvexPolygon.h" |
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30 | #include "StdVertexShader.h" |
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31 | #include "Trace.h" |
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32 | |
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33 | using namespace nv; |
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34 | using namespace vrmath; |
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35 | |
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36 | VolumeRenderer::VolumeRenderer() |
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37 | { |
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38 | initShaders(); |
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39 | |
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40 | _volumeInterpolator = new VolumeInterpolator(); |
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41 | } |
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42 | |
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43 | VolumeRenderer::~VolumeRenderer() |
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44 | { |
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45 | delete _cutplaneShader; |
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46 | delete _zincBlendeShader; |
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47 | delete _regularVolumeShader; |
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48 | delete _stdVertexShader; |
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49 | delete _volumeInterpolator; |
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50 | } |
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51 | |
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52 | //initialize the volume shaders |
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53 | void VolumeRenderer::initShaders() |
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54 | { |
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55 | _cutplaneShader = new Shader(); |
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56 | _cutplaneShader->loadVertexProgram("cutplane_vp.cg"); |
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57 | _cutplaneShader->loadFragmentProgram("cutplane_fp.cg"); |
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58 | |
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59 | //standard vertex program |
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60 | _stdVertexShader = new StdVertexShader(); |
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61 | |
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62 | //volume rendering shader: one cubic volume |
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63 | _regularVolumeShader = new RegularVolumeShader(); |
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64 | |
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65 | //volume rendering shader: one zincblende orbital volume. |
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66 | //This shader renders one orbital of the simulation. |
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67 | //A sim has S, P, D, SS orbitals. thus a full rendering requires 4 zincblende orbital volumes. |
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68 | //A zincblende orbital volume is decomposed into 2 "interlocking" cubic 4-component volumes and passed to the shader. |
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69 | //We render each orbital with independent transfer functions then blend the result. |
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70 | // |
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71 | //The engine is already capable of rendering multiple volumes and combine them. Thus, we just invoke this shader on |
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72 | //S, P, D and SS orbitals with different transfor functions. The result is a multi-orbital rendering. |
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73 | _zincBlendeShader = new ZincBlendeVolumeShader(); |
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74 | } |
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75 | |
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76 | struct SortElement { |
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77 | float z; |
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78 | int volumeId; |
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79 | int sliceId; |
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80 | |
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81 | SortElement(float _z, int _v, int _s) : |
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82 | z(_z), |
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83 | volumeId(_v), |
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84 | sliceId(_s) |
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85 | {} |
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86 | }; |
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87 | |
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88 | static int sliceSort(const void *a, const void *b) |
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89 | { |
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90 | if ((*((SortElement*)a)).z > (*((SortElement*)b)).z) |
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91 | return 1; |
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92 | else |
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93 | return -1; |
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94 | } |
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95 | |
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96 | void |
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97 | VolumeRenderer::renderAll() |
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98 | { |
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99 | size_t total_rendered_slices = 0; |
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100 | |
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101 | if (_volumeInterpolator->isStarted()) { |
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102 | #ifdef notdef |
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103 | ani_vol = _volumeInterpolator->getVolume(); |
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104 | ani_tf = ani_vol->transferFunction(); |
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105 | #endif |
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106 | TRACE("VOLUME INTERPOLATOR IS STARTED ----------------------------"); |
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107 | } |
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108 | // Determine the volumes that are to be rendered. |
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109 | std::vector<Volume *> volumes; |
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110 | for (NanoVis::VolumeHashmap::iterator itr = NanoVis::volumeTable.begin(); |
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111 | itr != NanoVis::volumeTable.end(); ++itr) { |
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112 | Volume *volume = itr->second; |
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113 | if (!volume->visible()) { |
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114 | continue; // Skip this volume |
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115 | } |
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116 | // BE CAREFUL: Set the number of slices to something slightly |
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117 | // different for each volume. If we have identical volumes at exactly |
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118 | // the same position with exactly the same number of slices, the |
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119 | // second volume will overwrite the first, so the first won't appear |
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120 | // at all. |
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121 | volumes.push_back(volume); |
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122 | volume->numSlices(256 - volumes.size()); |
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123 | } |
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124 | |
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125 | glPushAttrib(GL_ENABLE_BIT); |
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126 | |
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127 | //two dimension pointer array |
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128 | ConvexPolygon ***polys = new ConvexPolygon**[volumes.size()]; |
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129 | //number of actual slices for each volume |
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130 | size_t *actual_slices = new size_t[volumes.size()]; |
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131 | float *z_steps = new float[volumes.size()]; |
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132 | |
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133 | TRACE("start loop %d", volumes.size()); |
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134 | for (size_t i = 0; i < volumes.size(); i++) { |
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135 | Volume *volume = volumes[i]; |
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136 | polys[i] = NULL; |
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137 | actual_slices[i] = 0; |
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138 | |
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139 | int n_slices = volume->numSlices(); |
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140 | if (volume->isosurface()) { |
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141 | // double the number of slices |
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142 | n_slices <<= 1; |
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143 | } |
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144 | |
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145 | // Get any additional transforms on Volume |
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146 | Vector3f volPos = volume->getPosition(); |
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147 | Vector3f volScale = volume->getPhysicalScaling(); |
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148 | // Get world coords of volume bbox |
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149 | double x0 = 0; |
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150 | double y0 = 0; |
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151 | double z0 = 0; |
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152 | double x1 = x0 + 1; |
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153 | double y1 = y0 + 1; |
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154 | double z1 = z0 + 1; |
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155 | |
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156 | Matrix4x4d model_view_no_trans, model_view_trans; |
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157 | Matrix4x4d model_view_no_trans_inverse, model_view_trans_inverse; |
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158 | |
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159 | //initialize volume plane with world coordinates |
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160 | nv::Plane volume_planes[6]; |
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161 | volume_planes[0].setCoeffs( 1, 0, 0, -x0); |
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162 | volume_planes[1].setCoeffs(-1, 0, 0, x1); |
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163 | volume_planes[2].setCoeffs( 0, 1, 0, -y0); |
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164 | volume_planes[3].setCoeffs( 0, -1, 0, y1); |
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165 | volume_planes[4].setCoeffs( 0, 0, 1, -z0); |
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166 | volume_planes[5].setCoeffs( 0, 0, -1, z1); |
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167 | |
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168 | TRACE("VOL POS: %g %g %g", |
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169 | volPos.x, volPos.y, volPos.z); |
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170 | TRACE("VOL SCALE: %g %g %g", |
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171 | volScale.x, volScale.y, volScale.z); |
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172 | |
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173 | //get modelview matrix with no translation |
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174 | glPushMatrix(); |
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175 | glScalef(volScale.x, volScale.y, volScale.z); |
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176 | |
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177 | glEnable(GL_DEPTH_TEST); |
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178 | |
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179 | GLdouble mv_no_trans[16]; |
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180 | glGetDoublev(GL_MODELVIEW_MATRIX, mv_no_trans); |
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181 | |
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182 | model_view_no_trans = Matrix4x4d(mv_no_trans); |
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183 | model_view_no_trans_inverse = model_view_no_trans.inverse(); |
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184 | |
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185 | glPopMatrix(); |
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186 | |
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187 | //get modelview matrix with translation |
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188 | glPushMatrix(); |
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189 | glTranslatef(volPos.x, volPos.y, volPos.z); |
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190 | glScalef(volScale.x, volScale.y, volScale.z); |
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191 | |
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192 | GLdouble mv_trans[16]; |
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193 | glGetDoublev(GL_MODELVIEW_MATRIX, mv_trans); |
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194 | |
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195 | model_view_trans = Matrix4x4d(mv_trans); |
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196 | model_view_trans_inverse = model_view_trans.inverse(); |
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197 | |
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198 | model_view_trans.print(); |
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199 | |
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200 | //draw volume bounding box with translation (the correct location in |
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201 | //space) |
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202 | if (volume->outline()) { |
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203 | float olcolor[3]; |
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204 | volume->getOutlineColor(olcolor); |
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205 | drawBoundingBox(x0, y0, z0, x1, y1, z1, |
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206 | olcolor[0], olcolor[1], olcolor[2], |
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207 | 1.5); |
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208 | } |
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209 | glPopMatrix(); |
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210 | |
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211 | // transform volume_planes to eye coordinates. |
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212 | // Need to transform without translation since we don't want |
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213 | // to translate plane normals, just rotate them |
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214 | for (size_t j = 0; j < 6; j++) { |
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215 | volume_planes[j].transform(model_view_no_trans); |
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216 | } |
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217 | double eyeMinX, eyeMaxX, eyeMinY, eyeMaxY; |
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218 | double zNear, zFar; |
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219 | getEyeSpaceBounds(model_view_no_trans, |
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220 | eyeMinX, eyeMaxX, |
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221 | eyeMinY, eyeMaxY, |
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222 | zNear, zFar); |
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223 | |
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224 | //compute actual rendering slices |
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225 | float z_step = fabs(zNear-zFar)/n_slices; |
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226 | z_steps[i] = z_step; |
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227 | size_t n_actual_slices; |
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228 | |
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229 | if (volume->dataEnabled()) { |
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230 | if (z_step == 0.0f) |
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231 | n_actual_slices = 1; |
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232 | else |
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233 | n_actual_slices = (int)(fabs(zNear-zFar)/z_step + 1); |
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234 | polys[i] = new ConvexPolygon*[n_actual_slices]; |
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235 | } else { |
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236 | n_actual_slices = 0; |
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237 | polys[i] = NULL; |
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238 | } |
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239 | actual_slices[i] = n_actual_slices; |
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240 | |
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241 | TRACE("near: %g far: %g eye space bounds: (%g,%g)-(%g,%g) z_step: %g slices: %d", |
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242 | zNear, zFar, eyeMinX, eyeMaxX, eyeMinY, eyeMaxY, z_step, n_actual_slices); |
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243 | |
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244 | Vector4f vert1, vert2, vert3, vert4; |
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245 | |
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246 | // Render cutplanes first with depth test enabled. They will mark the |
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247 | // image with their depth values. Then we render other volume slices. |
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248 | // These volume slices will be occluded correctly by the cutplanes and |
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249 | // vice versa. |
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250 | |
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251 | for (int j = 0; j < volume->getCutplaneCount(); j++) { |
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252 | if (!volume->cutplanesVisible() || !volume->isCutplaneEnabled(j)) { |
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253 | continue; |
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254 | } |
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255 | Vector4f texcoord1, texcoord2, texcoord3, texcoord4; |
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256 | float offset = volume->getCutplane(j)->offset; |
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257 | int axis = volume->getCutplane(j)->orient; |
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258 | |
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259 | switch (axis) { |
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260 | case CutPlane::X_AXIS: // YZ plane |
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261 | vert1 = Vector4f(offset, 0, 0, 1); |
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262 | vert2 = Vector4f(offset, 1, 0, 1); |
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263 | vert3 = Vector4f(offset, 1, 1, 1); |
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264 | vert4 = Vector4f(offset, 0, 1, 1); |
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265 | texcoord1 = Vector4f(offset, 0, 0, 1); |
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266 | texcoord2 = Vector4f(offset, 1, 0, 1); |
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267 | texcoord3 = Vector4f(offset, 1, 1, 1); |
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268 | texcoord4 = Vector4f(offset, 0, 1, 1); |
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269 | break; |
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270 | case CutPlane::Y_AXIS: // XZ plane |
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271 | vert1 = Vector4f(0, offset, 0, 1); |
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272 | vert2 = Vector4f(1, offset, 0, 1); |
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273 | vert3 = Vector4f(1, offset, 1, 1); |
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274 | vert4 = Vector4f(0, offset, 1, 1); |
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275 | texcoord1 = Vector4f(0, offset, 0, 1); |
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276 | texcoord2 = Vector4f(1, offset, 0, 1); |
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277 | texcoord3 = Vector4f(1, offset, 1, 1); |
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278 | texcoord4 = Vector4f(0, offset, 1, 1); |
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279 | break; |
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280 | case CutPlane::Z_AXIS: // XY plane |
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281 | default: |
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282 | vert1 = Vector4f(0, 0, offset, 1); |
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283 | vert2 = Vector4f(1, 0, offset, 1); |
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284 | vert3 = Vector4f(1, 1, offset, 1); |
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285 | vert4 = Vector4f(0, 1, offset, 1); |
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286 | texcoord1 = Vector4f(0, 0, offset, 1); |
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287 | texcoord2 = Vector4f(1, 0, offset, 1); |
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288 | texcoord3 = Vector4f(1, 1, offset, 1); |
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289 | texcoord4 = Vector4f(0, 1, offset, 1); |
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290 | break; |
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291 | } |
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292 | |
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293 | _cutplaneShader->bind(); |
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294 | _cutplaneShader->setFPTextureParameter("volume", volume->textureID()); |
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295 | _cutplaneShader->setFPTextureParameter("tf", volume->transferFunction()->id()); |
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296 | |
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297 | glPushMatrix(); |
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298 | glTranslatef(volPos.x, volPos.y, volPos.z); |
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299 | glScalef(volScale.x, volScale.y, volScale.z); |
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300 | _cutplaneShader->setGLStateMatrixVPParameter("modelViewProjMatrix", |
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301 | Shader::MODELVIEW_PROJECTION_MATRIX); |
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302 | glPopMatrix(); |
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303 | |
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304 | glEnable(GL_DEPTH_TEST); |
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305 | glDisable(GL_BLEND); |
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306 | |
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307 | glBegin(GL_QUADS); |
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308 | glTexCoord3f(texcoord1.x, texcoord1.y, texcoord1.z); |
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309 | glVertex3f(vert1.x, vert1.y, vert1.z); |
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310 | glTexCoord3f(texcoord2.x, texcoord2.y, texcoord2.z); |
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311 | glVertex3f(vert2.x, vert2.y, vert2.z); |
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312 | glTexCoord3f(texcoord3.x, texcoord3.y, texcoord3.z); |
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313 | glVertex3f(vert3.x, vert3.y, vert3.z); |
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314 | glTexCoord3f(texcoord4.x, texcoord4.y, texcoord4.z); |
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315 | glVertex3f(vert4.x, vert4.y, vert4.z); |
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316 | glEnd(); |
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317 | |
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318 | glDisable(GL_DEPTH_TEST); |
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319 | _cutplaneShader->disableFPTextureParameter("tf"); |
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320 | _cutplaneShader->disableFPTextureParameter("volume"); |
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321 | _cutplaneShader->unbind(); |
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322 | } //done cutplanes |
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323 | |
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324 | // Now prepare proxy geometry slices |
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325 | |
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326 | // Initialize view-aligned quads with eye space bounds of |
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327 | // volume |
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328 | vert1 = Vector4f(eyeMinX, eyeMinY, -0.5, 1); |
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329 | vert2 = Vector4f(eyeMaxX, eyeMinY, -0.5, 1); |
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330 | vert3 = Vector4f(eyeMaxX, eyeMaxY, -0.5, 1); |
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331 | vert4 = Vector4f(eyeMinX, eyeMaxY, -0.5, 1); |
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332 | |
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333 | size_t counter = 0; |
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334 | |
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335 | // Transform slices and store them |
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336 | float slice_z; |
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337 | for (size_t j = 0; j < n_actual_slices; j++) { |
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338 | slice_z = zFar + j * z_step; //back to front |
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339 | |
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340 | ConvexPolygon *poly = new ConvexPolygon(); |
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341 | polys[i][counter] = poly; |
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342 | counter++; |
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343 | |
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344 | poly->vertices.clear(); |
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345 | poly->setId(i); |
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346 | |
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347 | // Set eye space Z-coordinate of slice |
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348 | vert1.z = slice_z; |
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349 | vert2.z = slice_z; |
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350 | vert3.z = slice_z; |
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351 | vert4.z = slice_z; |
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352 | |
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353 | poly->appendVertex(vert1); |
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354 | poly->appendVertex(vert2); |
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355 | poly->appendVertex(vert3); |
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356 | poly->appendVertex(vert4); |
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357 | |
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358 | for (size_t k = 0; k < 6; k++) { |
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359 | if (!poly->clip(volume_planes[k], true)) |
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360 | break; |
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361 | } |
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362 | |
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363 | if (poly->vertices.size() >= 3) { |
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364 | poly->transform(model_view_no_trans_inverse); |
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365 | poly->transform(model_view_trans); |
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366 | total_rendered_slices++; |
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367 | } |
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368 | } |
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369 | } //iterate all volumes |
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370 | TRACE("end loop"); |
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371 | |
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372 | // We sort all the polygons according to their eye-space depth, from |
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373 | // farthest to the closest. This step is critical for correct blending |
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374 | |
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375 | SortElement *slices = (SortElement *) |
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376 | malloc(sizeof(SortElement) * total_rendered_slices); |
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377 | |
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378 | size_t counter = 0; |
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379 | for (size_t i = 0; i < volumes.size(); i++) { |
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380 | for (size_t j = 0; j < actual_slices[i]; j++) { |
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381 | if (polys[i][j]->vertices.size() >= 3) { |
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382 | slices[counter] = SortElement(polys[i][j]->vertices[0].z, i, j); |
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383 | counter++; |
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384 | } |
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385 | } |
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386 | } |
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387 | |
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388 | //sort them |
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389 | qsort(slices, total_rendered_slices, sizeof(SortElement), sliceSort); |
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390 | |
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391 | //Now we are ready to render all the slices from back to front |
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392 | glEnable(GL_DEPTH_TEST); |
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393 | // Non pre-multiplied alpha |
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394 | glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); |
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395 | glEnable(GL_BLEND); |
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396 | |
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397 | for (size_t i = 0; i < total_rendered_slices; i++) { |
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398 | int volIdx = slices[i].volumeId; |
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399 | int sliceIdx = slices[i].sliceId; |
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400 | ConvexPolygon *currentSlice = polys[volIdx][sliceIdx]; |
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401 | |
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402 | Volume *volume = volumes[volIdx]; |
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403 | Vector3f volScale = volume->getPhysicalScaling(); |
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404 | |
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405 | glPushMatrix(); |
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406 | glScalef(volScale.x, volScale.y, volScale.z); |
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407 | |
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408 | float z_step = z_steps[volIdx]; |
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409 | // FIXME: compute view-dependent volume sample distance |
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410 | double avgSampleDistance = 1.0 / pow(volume->width() * volScale.x * |
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411 | volume->height() * volScale.y * |
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412 | volume->depth() * volScale.z, 1.0/3.0); |
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413 | float sampleRatio = z_step / avgSampleDistance; |
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414 | |
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415 | #ifdef notdef |
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416 | TRACE("shading slice: volume %s addr=%x slice=%d, volume=%d z_step=%g avgSD=%g", |
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417 | volume->name(), volume, sliceIdx, volIdx, z_step, avgSampleDistance); |
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418 | #endif |
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419 | activateVolumeShader(volume, false, sampleRatio); |
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420 | glPopMatrix(); |
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421 | |
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422 | glBegin(GL_POLYGON); |
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423 | currentSlice->emit(true); |
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424 | glEnd(); |
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425 | |
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426 | deactivateVolumeShader(); |
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427 | } |
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428 | |
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429 | glPopAttrib(); |
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430 | |
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431 | //Deallocate all the memory used |
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432 | for (size_t i = 0; i < volumes.size(); i++) { |
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433 | for (size_t j = 0; j <actual_slices[i]; j++) { |
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434 | delete polys[i][j]; |
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435 | } |
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436 | if (polys[i]) { |
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437 | delete[] polys[i]; |
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438 | } |
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439 | } |
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440 | delete[] polys; |
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441 | delete[] actual_slices; |
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442 | delete[] z_steps; |
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443 | free(slices); |
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444 | } |
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445 | |
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446 | void |
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447 | VolumeRenderer::drawBoundingBox(float x0, float y0, float z0, |
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448 | float x1, float y1, float z1, |
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449 | float r, float g, float b, |
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450 | float lineWidth) |
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451 | { |
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452 | glPushAttrib(GL_ENABLE_BIT); |
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453 | |
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454 | glEnable(GL_DEPTH_TEST); |
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455 | glDisable(GL_TEXTURE_2D); |
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456 | glEnable(GL_BLEND); |
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457 | |
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458 | glMatrixMode(GL_MODELVIEW); |
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459 | glPushMatrix(); |
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460 | |
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461 | glColor4d(r, g, b, 1.0); |
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462 | glLineWidth(lineWidth); |
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463 | |
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464 | glBegin(GL_LINE_LOOP); |
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465 | { |
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466 | glVertex3d(x0, y0, z0); |
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467 | glVertex3d(x1, y0, z0); |
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468 | glVertex3d(x1, y1, z0); |
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469 | glVertex3d(x0, y1, z0); |
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470 | } |
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471 | glEnd(); |
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472 | |
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473 | glBegin(GL_LINE_LOOP); |
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474 | { |
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475 | glVertex3d(x0, y0, z1); |
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476 | glVertex3d(x1, y0, z1); |
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477 | glVertex3d(x1, y1, z1); |
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478 | glVertex3d(x0, y1, z1); |
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479 | } |
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480 | glEnd(); |
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481 | |
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482 | glBegin(GL_LINE_LOOP); |
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483 | { |
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484 | glVertex3d(x0, y0, z0); |
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485 | glVertex3d(x0, y0, z1); |
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486 | glVertex3d(x0, y1, z1); |
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487 | glVertex3d(x0, y1, z0); |
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488 | } |
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489 | glEnd(); |
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490 | |
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491 | glBegin(GL_LINE_LOOP); |
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492 | { |
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493 | glVertex3d(x1, y0, z0); |
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494 | glVertex3d(x1, y0, z1); |
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495 | glVertex3d(x1, y1, z1); |
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496 | glVertex3d(x1, y1, z0); |
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497 | } |
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498 | glEnd(); |
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499 | |
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500 | glPopMatrix(); |
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501 | glPopAttrib(); |
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502 | } |
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503 | |
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504 | void |
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505 | VolumeRenderer::activateVolumeShader(Volume *volume, |
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506 | bool sliceMode, |
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507 | float sampleRatio) |
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508 | { |
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509 | //vertex shader |
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510 | _stdVertexShader->bind(); |
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511 | TransferFunction *transferFunc = volume->transferFunction(); |
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512 | if (volume->volumeType() == Volume::CUBIC) { |
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513 | _regularVolumeShader->bind(transferFunc->id(), volume, sliceMode, sampleRatio); |
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514 | } else if (volume->volumeType() == Volume::ZINCBLENDE) { |
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515 | _zincBlendeShader->bind(transferFunc->id(), volume, sliceMode, sampleRatio); |
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516 | } |
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517 | } |
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518 | |
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519 | void VolumeRenderer::deactivateVolumeShader() |
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520 | { |
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521 | _stdVertexShader->unbind(); |
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522 | _regularVolumeShader->unbind(); |
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523 | _zincBlendeShader->unbind(); |
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524 | } |
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525 | |
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526 | void VolumeRenderer::getEyeSpaceBounds(const Matrix4x4d& mv, |
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527 | double& xMin, double& xMax, |
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528 | double& yMin, double& yMax, |
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529 | double& zNear, double& zFar) |
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530 | { |
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531 | double x0 = 0; |
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532 | double y0 = 0; |
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533 | double z0 = 0; |
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534 | double x1 = 1; |
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535 | double y1 = 1; |
---|
536 | double z1 = 1; |
---|
537 | |
---|
538 | double zMin, zMax; |
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539 | xMin = DBL_MAX; |
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540 | xMax = -DBL_MAX; |
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541 | yMin = DBL_MAX; |
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542 | yMax = -DBL_MAX; |
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543 | zMin = DBL_MAX; |
---|
544 | zMax = -DBL_MAX; |
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545 | |
---|
546 | double vertex[8][4]; |
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547 | |
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548 | vertex[0][0]=x0; vertex[0][1]=y0; vertex[0][2]=z0; vertex[0][3]=1.0; |
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549 | vertex[1][0]=x1; vertex[1][1]=y0; vertex[1][2]=z0; vertex[1][3]=1.0; |
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550 | vertex[2][0]=x0; vertex[2][1]=y1; vertex[2][2]=z0; vertex[2][3]=1.0; |
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551 | vertex[3][0]=x0; vertex[3][1]=y0; vertex[3][2]=z1; vertex[3][3]=1.0; |
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552 | vertex[4][0]=x1; vertex[4][1]=y1; vertex[4][2]=z0; vertex[4][3]=1.0; |
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553 | vertex[5][0]=x1; vertex[5][1]=y0; vertex[5][2]=z1; vertex[5][3]=1.0; |
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554 | vertex[6][0]=x0; vertex[6][1]=y1; vertex[6][2]=z1; vertex[6][3]=1.0; |
---|
555 | vertex[7][0]=x1; vertex[7][1]=y1; vertex[7][2]=z1; vertex[7][3]=1.0; |
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556 | |
---|
557 | for (int i = 0; i < 8; i++) { |
---|
558 | Vector4f eyeVert = mv.transform(Vector4f(vertex[i][0], |
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559 | vertex[i][1], |
---|
560 | vertex[i][2], |
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561 | vertex[i][3])); |
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562 | if (eyeVert.x < xMin) xMin = eyeVert.x; |
---|
563 | if (eyeVert.x > xMax) xMax = eyeVert.x; |
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564 | if (eyeVert.y < yMin) yMin = eyeVert.y; |
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565 | if (eyeVert.y > yMax) yMax = eyeVert.y; |
---|
566 | if (eyeVert.z < zMin) zMin = eyeVert.z; |
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567 | if (eyeVert.z > zMax) zMax = eyeVert.z; |
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568 | } |
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569 | |
---|
570 | zNear = zMax; |
---|
571 | zFar = zMin; |
---|
572 | } |
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