1 | #include "ShadowMapping.h"
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2 | #include "FrameBufferObject.h"
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3 | #include "RenderState.h"
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4 | #include "RenderTraverser.h"
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5 | #include "Light.h"
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6 | #include "Polygon3.h"
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7 | #include "Polyhedron.h"
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8 |
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9 | #include <IL/il.h>
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10 | #include <assert.h>
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11 |
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12 |
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13 | using namespace std;
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14 |
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15 |
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16 | namespace CHCDemoEngine
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17 | {
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18 |
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19 | static CGprogram sCgShadowProgram;
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20 | static CGparameter sShadowParam;
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21 |
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22 |
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23 | static Polyhedron *polyhedron = NULL;
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24 | static Polyhedron *lightPoly = NULL;
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25 |
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26 |
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27 | static void PrintGLerror(char *msg)
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28 | {
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29 | GLenum errCode;
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30 | const GLubyte *errStr;
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31 |
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32 | if ((errCode = glGetError()) != GL_NO_ERROR)
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33 | {
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34 | errStr = gluErrorString(errCode);
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35 | fprintf(stderr,"OpenGL ERROR: %s: %s\n", errStr, msg);
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36 | }
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37 | }
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38 |
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39 |
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40 | static Polyhedron *CreatePolyhedron(const Matrix4x4 &lightMatrix,
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41 | const AxisAlignedBox3 &sceneBox)
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42 | {
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43 | Frustum frustum(lightMatrix);
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44 |
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45 | vector<Plane3> clipPlanes;
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46 |
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47 | for (int i = 0; i < 6; ++ i)
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48 | {
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49 | ////////////
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50 | //-- normalize the coefficients
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51 |
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52 | // the clipping planes look outward the frustum,
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53 | // so distances > 0 mean that a point is outside
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54 | const float invLength = -1.0f / Magnitude(frustum.mClipPlanes[i].mNormal);
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55 |
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56 | frustum.mClipPlanes[i].mD *= invLength;
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57 | frustum.mClipPlanes[i].mNormal *= invLength;
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58 | }
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59 |
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60 | // first create near plane because of precision issues
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61 | clipPlanes.push_back(frustum.mClipPlanes[4]);
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62 |
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63 | clipPlanes.push_back(frustum.mClipPlanes[0]);
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64 | clipPlanes.push_back(frustum.mClipPlanes[1]);
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65 | clipPlanes.push_back(frustum.mClipPlanes[2]);
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66 | clipPlanes.push_back(frustum.mClipPlanes[3]);
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67 | clipPlanes.push_back(frustum.mClipPlanes[5]);
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68 |
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69 | return Polyhedron::CreatePolyhedron(clipPlanes, sceneBox);
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70 | }
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71 |
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72 |
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73 | static void GrabDepthBuffer(float *data, GLuint depthTexture)
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74 | {
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75 | glEnable(GL_TEXTURE_2D);
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76 | glBindTexture(GL_TEXTURE_2D, depthTexture);
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77 |
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78 | glGetTexImage(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, GL_FLOAT, data);
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79 |
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80 | glBindTexture(GL_TEXTURE_2D, 0);
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81 | glDisable(GL_TEXTURE_2D);
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82 | }
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83 |
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84 |
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85 | static void ExportDepthBuffer(float *data, int size)
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86 | {
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87 | ilInit();
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88 | assert(ilGetError() == IL_NO_ERROR);
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89 |
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90 | ILstring filename = ILstring("shadow.tga");
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91 | ilRegisterType(IL_FLOAT);
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92 |
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93 | const int depth = 1;
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94 | const int bpp = 1;
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95 |
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96 | if (!ilTexImage(size, size, depth, bpp, IL_LUMINANCE, IL_FLOAT, data))
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97 | {
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98 | cerr << "IL error " << ilGetError() << endl;
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99 |
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100 | ilShutDown();
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101 | assert(ilGetError() == IL_NO_ERROR);
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102 |
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103 | return;
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104 | }
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105 |
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106 | if (!ilSaveImage(filename))
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107 | {
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108 | cerr << "TGA write error " << ilGetError() << endl;
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109 | }
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110 |
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111 | ilShutDown();
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112 | assert(ilGetError() == IL_NO_ERROR);
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113 |
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114 | cout << "exported depth buffer" << endl;
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115 | }
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116 |
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117 |
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118 |
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119 | static AxisAlignedBox3 GetExtremalPoints(const Matrix4x4 &m,
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120 | const VertexArray &pts)
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121 | {
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122 | AxisAlignedBox3 extremalPoints;
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123 | extremalPoints.Initialize();
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124 |
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125 | VertexArray::const_iterator it, it_end = pts.end();
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126 |
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127 | for (it = pts.begin(); it != it_end; ++ it)
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128 | {
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129 | Vector3 pt = *it;
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130 | pt = m * pt;
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131 |
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132 | extremalPoints.Include(pt);
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133 | }
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134 |
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135 | return extremalPoints;
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136 | }
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137 |
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138 |
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139 | ShadowMap::ShadowMap(DirectionalLight *light
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140 | , int size,
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141 | const AxisAlignedBox3 &sceneBox,
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142 | Camera *cam):
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143 | mSceneBox(sceneBox), mSize(size), mCamera(cam), mLight(light)
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144 | {
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145 | mFbo = new FrameBufferObject(size, size, FrameBufferObject::DEPTH_32, true);
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146 |
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147 | // need a color buffer to keep opengl happy
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148 | mFbo->AddColorBuffer(ColorBufferObject::RGB_UBYTE,
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149 | ColorBufferObject::WRAP_CLAMP_TO_EDGE,
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150 | ColorBufferObject::FILTER_NEAREST);
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151 |
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152 |
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153 | mShadowCam = new Camera(mSize, mSize);
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154 | mShadowCam->SetOrtho(true);
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155 | }
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156 |
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157 |
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158 | ShadowMap::~ShadowMap()
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159 | {
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160 | DEL_PTR(mFbo);
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161 | DEL_PTR(mShadowCam);
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162 |
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163 | DEL_PTR(lightPoly);
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164 | DEL_PTR(polyhedron);
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165 | }
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166 |
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167 |
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168 | static void DrawPolyhedron(Polyhedron *poly, const Vector3 &color)
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169 | {
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170 | if (!poly) return;
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171 |
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172 | for (size_t i = 0; i < poly->NumPolygons(); ++ i)
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173 | {
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174 | glColor3f(color.x, color.y, color.z);
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175 |
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176 | glBegin(GL_LINE_LOOP);
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177 |
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178 | Polygon3 *p = poly->GetPolygons()[i];
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179 |
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180 | for (size_t j = 0; j < p->mVertices.size(); ++ j)
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181 | {
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182 | Vector3 v = p->mVertices[j];
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183 | glVertex3d(v.x, v.y, v.z);
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184 | }
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185 |
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186 | glEnd();
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187 | }
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188 | }
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189 |
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190 |
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191 | void ShadowMap::VisualizeFrustra()
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192 | {
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193 | DrawPolyhedron(lightPoly, Vector3(1, 0, 1));
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194 | DrawPolyhedron(polyhedron, Vector3(0, 1, 0));
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195 | }
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196 |
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197 |
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198 | // z0 is the point that lies on the parallel plane to the near plane through e (A)
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199 | //and on the near plane of the C frustum (the plane z = bZmax) and on the line x = e.x
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200 | Vector3 ShadowMap::GetLightSpaceZ0(const Matrix4x4 &lightSpace,
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201 | const Vector3 &e,
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202 | const float maxZ,
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203 | const Vector3 &eyeDir) const
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204 | {
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205 | // to calculate the parallel plane to the near plane through e we
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206 | // calculate the plane A with the three points
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207 | Plane3 planeA(e, eyeDir);
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208 |
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209 | planeA.Transform(lightSpace);
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210 |
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211 | // get the parameters of A from the plane equation n dot d = 0
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212 | const float d = planeA.mD;
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213 | const Vector3 n = planeA.mNormal;
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214 |
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215 | // transform to light space
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216 | const Vector3 e_ls = lightSpace * e;
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217 |
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218 | Vector3 z0;
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219 |
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220 | z0.x = e_ls.x;
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221 | z0.y = (d - n.z * maxZ - n.x * e_ls.x) / n.y;
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222 | z0.z = maxZ;
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223 |
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224 | return z0;
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225 | //return V3(e_ls.x(),(d-n.z()*b_lsZmax-n.x()*e_ls.x())/n.y(),b_lsZmax);
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226 | }
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227 |
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228 |
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229 | float ShadowMap::ComputeNOpt(const Matrix4x4 &lightSpace,
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230 | const AxisAlignedBox3 &extremalPoints,
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231 | const VertexArray &body) const
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232 | {
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233 | const Vector3 nearPt = GetNearCameraPointE(body);
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234 | const Vector3 eyeDir = mCamera->GetDirection();
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235 |
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236 | Matrix4x4 eyeView;
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237 | mCamera->GetModelViewMatrix(eyeView);
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238 |
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239 | const Matrix4x4 invLightSpace = Invert(lightSpace);
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240 |
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241 | const Vector3 z0_ls = GetLightSpaceZ0(lightSpace, nearPt, extremalPoints.Max().z, eyeDir);
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242 | const Vector3 z1_ls = Vector3(z0_ls.x, z0_ls.y, extremalPoints.Min().z);
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243 |
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244 | // transform back to world space
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245 | const Vector3 z0_ws = invLightSpace * z0_ls;
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246 | const Vector3 z1_ws = invLightSpace * z1_ls;
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247 |
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248 | // transform to eye space
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249 | const Vector3 z0_es = eyeView * z0_ws;
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250 | const Vector3 z1_es = eyeView * z1_ws;
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251 |
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252 | const float z0 = z0_es.z;
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253 | const float z1 = z1_es.z;
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254 |
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255 | cout << "z0 ls: " << z0_ls << " z1 ls: " << z1_ls << endl;
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256 | cout << "z0: " << z0_es << " z1: " << z1_es << endl;
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257 |
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258 | const float d = fabs(extremalPoints.Max()[2] - extremalPoints.Min()[2]);
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259 |
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260 | const float n = d / (sqrt(z1 / z0) - 1.0f);
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261 |
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262 | return n;
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263 | }
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264 |
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265 |
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266 | float ShadowMap::ComputeN(const AxisAlignedBox3 &extremalPoints) const
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267 | {
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268 | const float nearPlane = mCamera->GetNear();
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269 |
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270 | const float d = fabs(extremalPoints.Max()[2] - extremalPoints.Min()[2]);
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271 |
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272 | const float dotProd = DotProd(mCamera->GetDirection(), mShadowCam->GetDirection());
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273 | const float sinGamma = sin(fabs(acos(dotProd)));
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274 |
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275 | // test for values close to zero
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276 | if (sinGamma < 1e-6f) return 1e6f;
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277 |
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278 | const float scale = 2.0f;
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279 | return scale * (nearPlane + sqrt(nearPlane * (nearPlane + d * sinGamma))) / sinGamma;
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280 | }
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281 |
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282 |
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283 | Matrix4x4 ShadowMap::CalcLispSMTransform(const Matrix4x4 &lightSpace,
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284 | const AxisAlignedBox3 &extremalPoints,
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285 | const VertexArray &body
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286 | )
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287 | {
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288 | AxisAlignedBox3 bounds_ls = GetExtremalPoints(lightSpace, body);
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289 |
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290 | ///////////////
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291 | //-- We apply the lispsm algorithm in order to calculate an optimal light projection matrix
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292 | //-- first find the free parameter values n, and P (the projection center), and the projection depth
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293 |
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294 | const float n = ComputeN(bounds_ls);
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295 | //const float n = ComputeNOpt(lightSpace, extremalPoints, body); cout << "n: " << n << endl;
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296 |
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297 | if (n >= 1e6f) // light direction nearly parallel to view => switch to uniform
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298 | return IdentityMatrix();
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299 |
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300 | const Vector3 nearPt = GetNearCameraPointE(body);
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301 |
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302 | //get the coordinates of the near camera point in light space
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303 | const Vector3 lsNear = lightSpace * nearPt;
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304 |
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305 | // the start point has the x and y coordinate of e, the z coord of the near plane of the light volume
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306 | const Vector3 startPt = Vector3(lsNear.x, lsNear.y, bounds_ls.Max().z);
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307 |
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308 | // the new projection center
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309 | const Vector3 projCenter = startPt + Vector3::UNIT_Z() * n;
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310 |
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311 | //construct a translation that moves to the projection center
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312 | const Matrix4x4 projectionCenter = TranslationMatrix(-projCenter);
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313 |
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314 | // light space y size
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315 | const float d = fabs(bounds_ls.Max()[2] - bounds_ls.Min()[2]);
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316 |
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317 | const float dy = fabs(bounds_ls.Max()[1] - bounds_ls.Min()[1]);
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318 | const float dx = fabs(bounds_ls.Max()[0] - bounds_ls.Min()[0]);
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319 |
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320 |
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321 |
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322 | //////////
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323 | //-- now apply these values to construct the perspective lispsm matrix
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324 |
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325 | Matrix4x4 matLispSM;
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326 |
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327 | matLispSM = GetFrustum(-1.0, 1.0, -1.0, 1.0, n, n + d);
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328 |
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329 | // translate to the projection center
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330 | matLispSM = projectionCenter * matLispSM;
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331 |
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332 | // transform into OpenGL right handed system
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333 | Matrix4x4 refl = ScaleMatrix(1.0f, 1.0f, -1.0f);
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334 | matLispSM *= refl;
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335 |
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336 | return matLispSM;
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337 | }
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338 |
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339 | #if 0
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340 | Vector3 ShadowMap::GetNearCameraPointE(const VertexArray &pts) const
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341 | {
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342 | float maxDist = -1e25f;
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343 | Vector3 nearest = Vector3::ZERO();
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344 |
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345 | Matrix4x4 eyeView;
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346 | mCamera->GetModelViewMatrix(eyeView);
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347 |
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348 | VertexArray newPts;
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349 | polyhedron->CollectVertices(newPts);
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350 |
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351 | //the LVS volume is always in front of the camera
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352 | VertexArray::const_iterator it, it_end = pts.end();
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353 |
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354 | for (it = pts.begin(); it != it_end; ++ it)
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355 | {
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356 | Vector3 pt = *it;
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357 | Vector3 ptE = eyeView * pt;
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358 |
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359 | if (ptE.z > 0) cerr <<"should not happen " << ptE.z << endl;
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360 | else
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361 | if (ptE.z > maxDist)
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362 | {
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363 | cout << " d " << ptE.z;
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364 |
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365 | maxDist = ptE.z;
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366 | nearest = pt;
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367 | }
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368 | }
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369 |
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370 | // return Invert(eyeView) * nearest;
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371 | return nearest;
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372 | }
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373 |
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374 | #else
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375 |
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376 | Vector3 ShadowMap::GetNearCameraPointE(const VertexArray &pts) const
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377 | {
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378 | VertexArray newPts;
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379 | polyhedron->CollectVertices(newPts);
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380 |
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381 | Vector3 nearest = Vector3::ZERO();
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382 | float minDist = 1e25f;
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383 |
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384 | const Vector3 camPos = mCamera->GetPosition();
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385 |
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386 | VertexArray::const_iterator it, it_end = newPts.end();
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387 |
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388 | for (it = newPts.begin(); it != it_end; ++ it)
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389 | {
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390 | Vector3 pt = *it;
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391 |
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392 | const float dist = SqrDistance(pt, camPos);
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393 |
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394 | if (dist < minDist)
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395 | {
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396 | minDist = dist;
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397 | nearest = pt;
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398 | }
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399 | }
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400 |
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401 | return nearest;
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402 | }
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403 |
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404 | #endif
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405 |
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406 | Vector3 ShadowMap::GetProjViewDir(const Matrix4x4 &lightSpace,
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407 | const VertexArray &pts) const
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408 | {
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409 | //get the point in the LVS volume that is nearest to the camera
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410 | const Vector3 e = GetNearCameraPointE(pts);
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411 |
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412 | //construct edge to transform into light-space
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413 | const Vector3 b = e + mCamera->GetDirection();
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414 | //transform to light-space
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415 | const Vector3 e_lp = lightSpace * e;
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416 | const Vector3 b_lp = lightSpace * b;
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417 |
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418 | Vector3 projDir(b_lp - e_lp);
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419 |
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420 | //project the view direction into the shadow map plane
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421 | projDir.y = .0f;
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422 |
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423 | return Normalize(projDir);
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424 | }
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425 |
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426 |
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427 | bool ShadowMap::CalcLightProjection(Matrix4x4 &lightProj)
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428 | {
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429 | ///////////////////
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430 | //-- First step: calc frustum clipped by scene box
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431 |
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432 | DEL_PTR(polyhedron);
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433 | polyhedron = CalcClippedFrustum(mSceneBox);
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434 |
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435 | if (!polyhedron) return false; // something is wrong
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436 |
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437 | // include the part of the light volume that "sees" the frustum
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438 | // we only require frustum vertices
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439 |
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440 | VertexArray frustumPoints;
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441 | IncludeLightVolume(*polyhedron, frustumPoints, mLight->GetDirection(), mSceneBox);
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442 |
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443 |
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444 | ///////////////
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445 | //-- transform points from world view to light view and calculate extremal points
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446 |
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447 | Matrix4x4 lightView;
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448 | mShadowCam->GetModelViewMatrix(lightView);
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449 |
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450 | const AxisAlignedBox3 extremalPoints = GetExtremalPoints(lightView, frustumPoints);
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451 |
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452 | // we use directional lights, so the projection can be set to identity
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453 | lightProj = IdentityMatrix();
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454 |
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455 | // switch coordinate system to that used in the lispsm algorithm for calculations
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456 | Matrix4x4 transform2LispSM = ZeroMatrix();
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457 |
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458 | transform2LispSM.x[0][0] = 1.0f;
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459 | transform2LispSM.x[1][2] = -1.0f; // y => -z
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460 | transform2LispSM.x[2][1] = 1.0f; // z => y
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461 | transform2LispSM.x[3][3] = 1.0f;
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462 |
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463 |
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464 | //switch to the lightspace used in the article
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465 | lightProj *= transform2LispSM;
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466 |
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467 | const Vector3 projViewDir = GetProjViewDir(lightView * lightProj, frustumPoints);
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468 |
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469 | //do DirectionalLight Space Perspective shadow mapping
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470 | //rotate the lightspace so that the projected light view always points upwards
|
---|
471 | //calculate a frame matrix that uses the projViewDir[lightspace] as up vector
|
---|
472 | //look(from position, into the direction of the projected direction, with unchanged up-vector)
|
---|
473 | //const Matrix4x4 frame = MyLookAt2(Vector3::ZERO(), projViewDir, Vector3::UNIT_Y());
|
---|
474 | const Matrix4x4 frame = LookAt(Vector3::ZERO(), projViewDir, Vector3::UNIT_Y());
|
---|
475 |
|
---|
476 | lightProj *= frame;
|
---|
477 |
|
---|
478 | const Matrix4x4 matLispSM =
|
---|
479 | CalcLispSMTransform(lightView * lightProj, extremalPoints, frustumPoints);
|
---|
480 |
|
---|
481 | lightProj *= matLispSM;
|
---|
482 |
|
---|
483 | // change back to GL coordinate system
|
---|
484 | Matrix4x4 transformToGL = ZeroMatrix();
|
---|
485 |
|
---|
486 | transformToGL.x[0][0] = 1.0f;
|
---|
487 | transformToGL.x[1][2] = 1.0f; // z => y
|
---|
488 | transformToGL.x[2][1] = -1.0f; // y => -z
|
---|
489 | transformToGL.x[3][3] = 1.0f;
|
---|
490 |
|
---|
491 | lightProj *= transformToGL;
|
---|
492 |
|
---|
493 | AxisAlignedBox3 lightPts = GetExtremalPoints(lightView * lightProj, frustumPoints);
|
---|
494 |
|
---|
495 | // focus projection matrix on the extremal points => scale to unit cube
|
---|
496 | Matrix4x4 scaleTranslate = GetFittingProjectionMatrix(lightPts);
|
---|
497 |
|
---|
498 | lightProj = lightProj * scaleTranslate;
|
---|
499 |
|
---|
500 | Matrix4x4 mymat = lightView * lightProj;
|
---|
501 |
|
---|
502 | AxisAlignedBox3 lightPtsNew = GetExtremalPoints(mymat, frustumPoints);
|
---|
503 |
|
---|
504 | // we have to flip the signs in order to tranform to opengl right handed system
|
---|
505 | Matrix4x4 refl = ScaleMatrix(1, 1, -1);
|
---|
506 | lightProj *= refl;
|
---|
507 |
|
---|
508 | return true;
|
---|
509 | }
|
---|
510 |
|
---|
511 |
|
---|
512 | Polyhedron *ShadowMap::CalcClippedFrustum(const AxisAlignedBox3 &box) const
|
---|
513 | {
|
---|
514 | Polyhedron *p = mCamera->ComputeFrustum();
|
---|
515 |
|
---|
516 | Polyhedron *clippedPolyhedron = box.CalcIntersection(*p);
|
---|
517 | DEL_PTR(p);
|
---|
518 |
|
---|
519 | return clippedPolyhedron;
|
---|
520 | }
|
---|
521 |
|
---|
522 |
|
---|
523 | //calculates the up vector for the light coordinate frame
|
---|
524 | static Vector3 CalcUpVec(const Vector3 viewDir, const Vector3 lightDir)
|
---|
525 | {
|
---|
526 | //we do what gluLookAt does...
|
---|
527 | //left is the normalized vector perpendicular to lightDir and viewDir
|
---|
528 | //this means left is the normalvector of the yz-plane from the paper
|
---|
529 | Vector3 left = CrossProd(lightDir, viewDir);
|
---|
530 |
|
---|
531 | //we now can calculate the rotated(in the yz-plane) viewDir vector
|
---|
532 | //and use it as up vector in further transformations
|
---|
533 | Vector3 up = CrossProd(left, lightDir);
|
---|
534 |
|
---|
535 | return Normalize(up);
|
---|
536 | }
|
---|
537 |
|
---|
538 |
|
---|
539 | void ShadowMap::GetTextureMatrix(Matrix4x4 &m) const
|
---|
540 | {
|
---|
541 | m = mTextureMatrix;
|
---|
542 | }
|
---|
543 |
|
---|
544 |
|
---|
545 | unsigned int ShadowMap::GetDepthTexture() const
|
---|
546 | {
|
---|
547 | return mFbo->GetDepthTex();
|
---|
548 | }
|
---|
549 |
|
---|
550 | unsigned int ShadowMap::GetShadowColorTexture() const
|
---|
551 | {
|
---|
552 | return mFbo->GetColorBuffer(0)->GetTexture();
|
---|
553 |
|
---|
554 | }
|
---|
555 |
|
---|
556 |
|
---|
557 | void ShadowMap::IncludeLightVolume(const Polyhedron &polyhedron,
|
---|
558 | VertexArray &frustumPoints,
|
---|
559 | const Vector3 lightDir,
|
---|
560 | const AxisAlignedBox3 &sceneBox
|
---|
561 | )
|
---|
562 | {
|
---|
563 | // we don't need closed form anymore => just store vertices
|
---|
564 | VertexArray vertices;
|
---|
565 | polyhedron.CollectVertices(vertices);
|
---|
566 |
|
---|
567 | // we 'look' at each point and calculate intersections of rays with scene bounding box
|
---|
568 | VertexArray::const_iterator it, it_end = vertices.end();
|
---|
569 |
|
---|
570 | for (it = vertices.begin(); it != it_end; ++ it)
|
---|
571 | {
|
---|
572 | Vector3 v = *it;
|
---|
573 |
|
---|
574 | frustumPoints.push_back(v);
|
---|
575 |
|
---|
576 | // hack: start at point which is guaranteed to be outside of box
|
---|
577 | v -= Magnitude(mSceneBox.Diagonal()) * lightDir;
|
---|
578 |
|
---|
579 | SimpleRay ray(v, lightDir);
|
---|
580 |
|
---|
581 | float tNear, tFar;
|
---|
582 |
|
---|
583 | if (sceneBox.Intersects(ray, tNear, tFar))
|
---|
584 | {
|
---|
585 | Vector3 newpt = ray.Extrap(tNear);
|
---|
586 | frustumPoints.push_back(newpt);
|
---|
587 | }
|
---|
588 | }
|
---|
589 | }
|
---|
590 |
|
---|
591 |
|
---|
592 | void ShadowMap::ComputeShadowMap(RenderTraverser *renderer, const Matrix4x4 &projView)
|
---|
593 | {
|
---|
594 | mFbo->Bind();
|
---|
595 |
|
---|
596 | glDrawBuffers(1, mrt);
|
---|
597 |
|
---|
598 | glPushAttrib(GL_VIEWPORT_BIT);
|
---|
599 | glViewport(0, 0, mSize, mSize);
|
---|
600 |
|
---|
601 | glDisable(GL_LIGHTING);
|
---|
602 | glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
|
---|
603 |
|
---|
604 | glShadeModel(GL_FLAT);
|
---|
605 |
|
---|
606 |
|
---|
607 | /////////////
|
---|
608 | //-- render scene into shadow map
|
---|
609 |
|
---|
610 | _Render(renderer);
|
---|
611 |
|
---|
612 |
|
---|
613 | //////////////
|
---|
614 | //-- compute texture matrix
|
---|
615 |
|
---|
616 | static Matrix4x4 biasMatrix(0.5f, 0.0f, 0.0f, 0.5f,
|
---|
617 | 0.0f, 0.5f, 0.0f, 0.5f,
|
---|
618 | 0.0f, 0.0f, 0.5f, 0.5f,
|
---|
619 | 0.0f, 0.0f, 0.0f, 1.0f);
|
---|
620 |
|
---|
621 | mTextureMatrix = mLightProjView * biasMatrix;
|
---|
622 |
|
---|
623 | glPopAttrib();
|
---|
624 |
|
---|
625 | glShadeModel(GL_SMOOTH);
|
---|
626 | glEnable(GL_LIGHTING);
|
---|
627 | glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
|
---|
628 |
|
---|
629 | #if 0
|
---|
630 | float *data = new float[mSize * mSize];
|
---|
631 |
|
---|
632 | GrabDepthBuffer(data, mFbo->GetDepthTex());
|
---|
633 | ExportDepthBuffer(data, mSize);
|
---|
634 |
|
---|
635 | delete [] data;
|
---|
636 |
|
---|
637 | PrintGLerror("shadow map");
|
---|
638 | #endif
|
---|
639 |
|
---|
640 | FrameBufferObject::Release();
|
---|
641 | }
|
---|
642 |
|
---|
643 |
|
---|
644 | void ShadowMap::RenderShadowView(RenderTraverser *renderer, const Matrix4x4 &projView)
|
---|
645 | {
|
---|
646 | glEnable(GL_LIGHTING);
|
---|
647 |
|
---|
648 | _Render(renderer);
|
---|
649 |
|
---|
650 | /*glDisable(GL_LIGHTING);
|
---|
651 | glDisable(GL_DEPTH_TEST);
|
---|
652 |
|
---|
653 | Polyhedron *hpoly = CreatePolyhedron(projView, mSceneBox);
|
---|
654 | DrawPoly(hpoly, Vector3(1, 1, 1));
|
---|
655 | DEL_PTR(hpoly);
|
---|
656 |
|
---|
657 | glEnable(GL_LIGHTING);
|
---|
658 | glEnable(GL_DEPTH_TEST);*/
|
---|
659 |
|
---|
660 | glDisable(GL_POLYGON_OFFSET_FILL);
|
---|
661 | }
|
---|
662 |
|
---|
663 |
|
---|
664 | void ShadowMap::_Render(RenderTraverser *renderer)
|
---|
665 | {
|
---|
666 | const Vector3 dir = mLight->GetDirection();
|
---|
667 |
|
---|
668 | mShadowCam->SetDirection(dir);
|
---|
669 |
|
---|
670 | // set position so that we can see the whole scene
|
---|
671 | Vector3 pos = mSceneBox.Center();
|
---|
672 | pos -= dir * Magnitude(mSceneBox.Diagonal() * 0.5f);
|
---|
673 |
|
---|
674 | mShadowCam->SetPosition(mCamera->GetPosition());
|
---|
675 |
|
---|
676 | Vector3 upVec = CalcUpVec(mCamera->GetDirection(), dir);
|
---|
677 | Matrix4x4 lightView = LookAt(mShadowCam->GetPosition(), dir, upVec);
|
---|
678 |
|
---|
679 | mShadowCam->mViewOrientation = lightView;
|
---|
680 |
|
---|
681 | glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
|
---|
682 |
|
---|
683 | glPolygonOffset(5.0f, 100.0f);
|
---|
684 | glEnable(GL_POLYGON_OFFSET_FILL);
|
---|
685 |
|
---|
686 | Matrix4x4 lightProj;
|
---|
687 | CalcLightProjection(lightProj);
|
---|
688 |
|
---|
689 | glMatrixMode(GL_PROJECTION);
|
---|
690 | glPushMatrix();
|
---|
691 | glLoadMatrixf((float *)lightProj.x);
|
---|
692 |
|
---|
693 | mLightProjView = lightView * lightProj;
|
---|
694 |
|
---|
695 | DEL_PTR(lightPoly);
|
---|
696 | lightPoly = CreatePolyhedron(mLightProjView, mSceneBox);
|
---|
697 |
|
---|
698 | glMatrixMode(GL_MODELVIEW);
|
---|
699 | glPushMatrix();
|
---|
700 |
|
---|
701 | mShadowCam->SetupCameraView();
|
---|
702 |
|
---|
703 |
|
---|
704 | /////////////
|
---|
705 | //-- render scene into shadow map
|
---|
706 |
|
---|
707 | renderer->RenderScene();
|
---|
708 |
|
---|
709 |
|
---|
710 | glMatrixMode(GL_PROJECTION);
|
---|
711 | glPopMatrix();
|
---|
712 |
|
---|
713 | glMatrixMode(GL_MODELVIEW);
|
---|
714 | glPopMatrix();
|
---|
715 |
|
---|
716 | glDisable(GL_POLYGON_OFFSET_FILL);
|
---|
717 | }
|
---|
718 | } // namespace
|
---|