1 | #ifndef _VspBspTree_H__ |
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2 | #define _VspBspTree_H__ |
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3 | |
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4 | #include "Mesh.h" |
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5 | #include "Containers.h" |
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6 | #include "Polygon3.h" |
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7 | #include <stack> |
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8 | #include "Statistics.h" |
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9 | #include "VssRay.h" |
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10 | #include "RayInfo.h" |
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11 | |
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12 | class ViewCell; |
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13 | class BspViewCell; |
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14 | class Plane3; |
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15 | class VspBspTree; |
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16 | class VspBspInterior; |
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17 | class VspBspNode; |
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18 | class AxisAlignedBox3; |
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19 | class Ray; |
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20 | |
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21 | class VspBspNodeGeometry |
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22 | { |
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23 | public: |
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24 | VspBspNodeGeometry() |
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25 | {}; |
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26 | |
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27 | ~VspBspNodeGeometry(); |
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28 | |
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29 | float GetArea() const; |
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30 | |
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31 | /** Computes new cell based on the old cell definition and a new split plane |
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32 | @param side indicates which side of the halfspace |
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33 | */ |
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34 | void SplitGeometry(VspBspNodeGeometry &front, |
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35 | VspBspNodeGeometry &back, |
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36 | const VspBspTree &tree, |
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37 | const Plane3 &splitPlane) const; |
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38 | |
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39 | Polygon3 *SplitPolygon(Polygon3 *poly, const VspBspTree &tree) const; |
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40 | |
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41 | PolygonContainer mPolys; |
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42 | }; |
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43 | |
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44 | /** Data structure used for optimized ray casting. |
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45 | */ |
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46 | struct VspBspRayTraversalData |
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47 | { |
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48 | VspBspNode *mNode; |
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49 | Vector3 mExitPoint; |
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50 | float mMaxT; |
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51 | |
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52 | VspBspRayTraversalData() {} |
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53 | |
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54 | VspBspRayTraversalData(VspBspNode *n, const Vector3 &extp, const float maxt): |
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55 | mNode(n), mExitPoint(extp), mMaxT(maxt) |
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56 | {} |
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57 | }; |
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58 | |
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59 | class VspBspTreeStatistics: public StatisticsBase |
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60 | { |
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61 | public: |
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62 | // total number of nodes |
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63 | int nodes; |
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64 | // number of splits |
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65 | int splits; |
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66 | // totals number of rays |
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67 | int rays; |
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68 | // maximal reached depth |
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69 | int maxDepth; |
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70 | // minimal depth |
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71 | int minDepth; |
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72 | |
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73 | // max depth nodes |
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74 | int maxDepthNodes; |
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75 | // minimum depth nodes
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76 | int minDepthNodes;
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77 | // max depth nodes
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78 | int minPvsNodes;
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79 | // nodes with minimum PVS
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80 | int minRaysNodes;
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81 | // max ray contribution nodes
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82 | int maxRayContribNodes;
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83 | // minimum area nodes
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84 | int minAreaNodes; |
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85 | |
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86 | // max number of rays per node |
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87 | int maxObjectRefs; |
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88 | // accumulated depth (used to compute average) |
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89 | int accumDepth; |
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90 | // number of initial polygons |
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91 | int polys; |
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92 | /// samples contributing to pvs |
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93 | int contributingSamples; |
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94 | /// sample contributions to pvs |
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95 | int sampleContributions; |
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96 | /// largest pvs |
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97 | int largestPvs; |
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98 | |
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99 | // Constructor |
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100 | VspBspTreeStatistics() |
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101 | { |
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102 | Reset(); |
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103 | } |
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104 | |
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105 | int Nodes() const {return nodes;} |
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106 | int Interior() const { return nodes / 2; } |
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107 | int Leaves() const { return (nodes / 2) + 1; } |
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108 | |
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109 | // TODO: computation wrong |
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110 | double AvgDepth() const { return accumDepth / (double)Leaves();}; |
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111 | |
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112 | void Reset() |
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113 | { |
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114 | nodes = 0; |
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115 | splits = 0; |
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116 | |
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117 | maxDepth = 0; |
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118 | minDepth = 99999; |
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119 | polys = 0; |
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120 | accumDepth = 0; |
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121 | |
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122 | maxDepthNodes = 0;
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123 | minPvsNodes = 0;
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124 | minRaysNodes = 0;
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125 | maxRayContribNodes = 0; |
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126 | minAreaNodes = 0; |
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127 | |
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128 | contributingSamples = 0; |
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129 | sampleContributions = 0; |
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130 | } |
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131 | |
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132 | void Print(ostream &app) const; |
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133 | |
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134 | friend ostream &operator<<(ostream &s, const VspBspTreeStatistics &stat) |
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135 | { |
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136 | stat.Print(s); |
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137 | return s; |
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138 | } |
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139 | }; |
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140 | |
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141 | class VspBspViewCellsStatistics: public StatisticsBase |
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142 | { |
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143 | public: |
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144 | |
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145 | /// number of view cells |
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146 | int viewCells; |
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147 | |
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148 | /// size of the PVS |
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149 | int pvs; |
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150 | |
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151 | /// largest PVS of all view cells |
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152 | int maxPvs; |
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153 | |
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154 | /// smallest PVS of all view cells |
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155 | int minPvs; |
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156 | |
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157 | /// view cells with empty PVS |
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158 | int emptyPvs; |
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159 | |
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160 | /// number of bsp leaves covering the view space |
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161 | int bspLeaves; |
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162 | |
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163 | /// largest number of leaves covered by one view cell |
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164 | int maxVspBspLeaves; |
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165 | |
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166 | // Constructor |
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167 | VspBspViewCellsStatistics() |
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168 | { |
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169 | Reset(); |
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170 | } |
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171 | |
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172 | double AvgVspBspLeaves() const {return (double)bspLeaves / (double)viewCells;}; |
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173 | double AvgPvs() const {return (double)pvs / (double)viewCells;}; |
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174 | |
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175 | void Reset() |
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176 | { |
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177 | viewCells = 0; |
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178 | pvs = 0; |
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179 | maxPvs = 0; |
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180 | |
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181 | minPvs = 999999; |
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182 | emptyPvs = 0; |
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183 | bspLeaves = 0; |
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184 | maxVspBspLeaves = 0; |
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185 | } |
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186 | |
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187 | void Print(ostream &app) const; |
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188 | |
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189 | friend ostream &operator<<(ostream &s, const VspBspViewCellsStatistics &stat) |
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190 | { |
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191 | stat.Print(s); |
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192 | return s; |
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193 | } |
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194 | }; |
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195 | |
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196 | /** |
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197 | VspBspNode abstract class serving for interior and leaf node implementation |
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198 | */ |
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199 | class VspBspNode |
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200 | { |
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201 | friend class VspBspTree; |
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202 | |
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203 | public: |
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204 | VspBspNode(); |
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205 | virtual ~VspBspNode(){}; |
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206 | VspBspNode(VspBspInterior *parent); |
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207 | |
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208 | /** Determines whether this node is a leaf or not |
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209 | @return true if leaf |
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210 | */ |
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211 | virtual bool IsLeaf() const = 0; |
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212 | |
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213 | /** Determines whether this node is a root |
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214 | @return true if root |
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215 | */ |
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216 | virtual bool IsRoot() const; |
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217 | |
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218 | /** Returns parent node. |
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219 | */ |
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220 | VspBspInterior *GetParent(); |
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221 | |
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222 | /** Sets parent node. |
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223 | */ |
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224 | void SetParent(VspBspInterior *parent); |
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225 | |
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226 | |
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227 | static int sMailId; |
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228 | int mMailbox; |
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229 | |
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230 | void Mail() { mMailbox = sMailId; } |
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231 | static void NewMail() { ++ sMailId; } |
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232 | bool Mailed() const { return mMailbox == sMailId; } |
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233 | |
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234 | protected: |
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235 | |
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236 | /// parent of this node |
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237 | VspBspInterior *mParent; |
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238 | }; |
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239 | |
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240 | /** BSP interior node implementation |
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241 | */ |
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242 | class VspBspInterior : public VspBspNode |
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243 | { |
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244 | friend class VspBspTree; |
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245 | public: |
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246 | /** Standard contructor taking split plane as argument. |
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247 | */ |
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248 | VspBspInterior(const Plane3 &plane); |
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249 | ~VspBspInterior(); |
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250 | /** @return false since it is an interior node |
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251 | */ |
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252 | bool IsLeaf() const; |
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253 | |
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254 | VspBspNode *GetBack(); |
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255 | VspBspNode *GetFront(); |
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256 | |
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257 | Plane3 *GetPlane(); |
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258 | |
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259 | void ReplaceChildLink(VspBspNode *oldChild, VspBspNode *newChild); |
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260 | void SetupChildLinks(VspBspNode *b, VspBspNode *f); |
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261 | |
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262 | /** Splits polygons with respect to the split plane. |
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263 | @param polys the polygons to be split. the polygons are consumed and |
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264 | distributed to the containers frontPolys, backPolys, coincident. |
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265 | @param frontPolys returns the polygons in the front of the split plane |
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266 | @param backPolys returns the polygons in the back of the split plane |
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267 | @param coincident returns the polygons coincident to the split plane |
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268 | |
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269 | @returns the number of splits |
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270 | */ |
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271 | int SplitPolygons(PolygonContainer &polys, |
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272 | PolygonContainer &frontPolys, |
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273 | PolygonContainer &backPolys, |
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274 | PolygonContainer &coincident); |
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275 | |
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276 | friend ostream &operator<<(ostream &s, const VspBspInterior &A) |
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277 | { |
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278 | return s << A.mPlane; |
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279 | } |
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280 | |
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281 | protected: |
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282 | |
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283 | /// Splitting plane corresponding to this node |
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284 | Plane3 mPlane; |
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285 | /// back node |
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286 | VspBspNode *mBack; |
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287 | /// front node |
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288 | VspBspNode *mFront; |
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289 | }; |
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290 | |
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291 | /** BSP leaf node implementation. |
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292 | */ |
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293 | class VspBspLeaf : public VspBspNode |
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294 | { |
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295 | friend class VspBspTree; |
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296 | |
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297 | public: |
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298 | VspBspLeaf(); |
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299 | VspBspLeaf(BspViewCell *viewCell); |
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300 | VspBspLeaf(VspBspInterior *parent); |
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301 | VspBspLeaf(VspBspInterior *parent, BspViewCell *viewCell); |
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302 | |
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303 | /** @return true since it is an interior node |
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304 | */ |
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305 | bool IsLeaf() const; |
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306 | |
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307 | /** Returns pointer of view cell. |
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308 | */ |
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309 | BspViewCell *GetViewCell() const; |
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310 | |
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311 | /** Sets pointer to view cell. |
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312 | */ |
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313 | void SetViewCell(BspViewCell *viewCell); |
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314 | |
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315 | /** Adds ray sample contributions to the PVS. |
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316 | @param sampleContributions the number contributions of the samples |
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317 | @param contributingSampels the number of contributing rays |
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318 | |
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319 | */ |
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320 | void AddToPvs(const RayInfoContainer &rays, |
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321 | int &sampleContributions, |
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322 | int &contributingSamples, |
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323 | bool storeLeavesWithRays = false); |
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324 | |
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325 | protected: |
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326 | |
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327 | /// if NULL this does not correspond to feasible viewcell |
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328 | BspViewCell *mViewCell; |
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329 | }; |
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330 | |
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331 | /** Implementation of the view cell BSP tree. |
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332 | */ |
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333 | class VspBspTree |
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334 | { |
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335 | public: |
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336 | |
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337 | /** Additional data which is passed down the BSP tree during traversal. |
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338 | */ |
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339 | struct VspBspTraversalData |
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340 | { |
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341 | /// the current node |
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342 | VspBspNode *mNode; |
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343 | /// polygonal data for splitting |
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344 | PolygonContainer *mPolygons; |
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345 | /// current depth |
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346 | int mDepth; |
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347 | /// the view cell associated with this subdivsion |
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348 | ViewCell *mViewCell; |
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349 | /// rays piercing this node |
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350 | RayInfoContainer *mRays; |
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351 | /// area of current node |
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352 | float mArea; |
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353 | /// geometry of current node induced by split planes |
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354 | VspBspNodeGeometry *mGeometry; |
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355 | |
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356 | /// pvs size |
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357 | int mPvs; |
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358 | |
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359 | /** Returns average ray contribution. |
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360 | */ |
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361 | float GetAvgRayContribution() const |
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362 | { |
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363 | return (float)mPvs / ((float)mRays->size() + Limits::Small); |
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364 | } |
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365 | |
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366 | |
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367 | VspBspTraversalData(): |
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368 | mNode(NULL), |
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369 | mPolygons(NULL), |
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370 | mDepth(0), |
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371 | mViewCell(NULL), |
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372 | mRays(NULL), |
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373 | mPvs(0), |
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374 | mArea(0.0), |
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375 | mGeometry(NULL) |
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376 | {} |
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377 | |
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378 | VspBspTraversalData(VspBspNode *node, |
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379 | PolygonContainer *polys, |
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380 | const int depth, |
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381 | ViewCell *viewCell, |
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382 | RayInfoContainer *rays, |
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383 | int pvs, |
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384 | float area, |
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385 | VspBspNodeGeometry *cell): |
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386 | mNode(node), |
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387 | mPolygons(polys), |
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388 | mDepth(depth), |
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389 | mViewCell(viewCell), |
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390 | mRays(rays), |
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391 | mPvs(pvs), |
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392 | mArea(area), |
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393 | mGeometry(cell) |
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394 | {} |
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395 | }; |
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396 | |
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397 | typedef std::stack<VspBspTraversalData> VspBspTraversalStack; |
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398 | |
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399 | /** Default constructor creating an empty tree. |
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400 | @param viewCell view cell corresponding to unbounded space |
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401 | */ |
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402 | VspBspTree(BspViewCell *viewCell); |
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403 | |
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404 | ~VspBspTree(); |
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405 | |
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406 | const VspBspTreeStatistics &GetStatistics() const; |
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407 | |
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408 | |
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409 | /** Constructs the tree from a given set of rays. |
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410 | @param sampleRays the set of sample rays the construction is based on |
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411 | @param viewCells if not NULL, new view cells are |
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412 | created in the leafs and stored in the conatainer |
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413 | */ |
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414 | void Construct(const VssRayContainer &sampleRays); |
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415 | |
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416 | /** Returns list of BSP leaves. |
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417 | */ |
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418 | void CollectLeaves(vector<VspBspLeaf *> &leaves) const; |
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419 | |
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420 | /** Returns box which bounds the whole tree. |
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421 | */ |
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422 | AxisAlignedBox3 GetBoundingBox()const; |
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423 | |
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424 | /** Returns root of BSP tree. |
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425 | */ |
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426 | VspBspNode *GetRoot() const; |
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427 | |
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428 | /** Exports VspBsp tree to file. |
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429 | */ |
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430 | bool Export(const string filename); |
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431 | |
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432 | /** Collects the leaf view cells of the tree |
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433 | @param viewCells returns the view cells |
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434 | */ |
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435 | void CollectViewCells(ViewCellContainer &viewCells) const; |
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436 | |
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437 | /** A ray is cast possible intersecting the tree. |
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438 | @param the ray that is cast. |
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439 | @returns the number of intersections with objects stored in the tree. |
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440 | */ |
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441 | int CastRay(Ray &ray); |
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442 | |
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443 | /** Set to true if new view cells shall be generated in each leaf. |
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444 | */ |
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445 | void SetGenerateViewCells(int generateViewCells); |
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446 | |
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447 | /// bsp tree construction types |
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448 | enum {FROM_INPUT_VIEW_CELLS, FROM_SCENE_GEOMETRY, FROM_SAMPLES}; |
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449 | |
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450 | /** Returns statistics. |
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451 | */ |
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452 | VspBspTreeStatistics &GetStat(); |
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453 | |
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454 | /** finds neighbouring leaves of this tree node. |
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455 | */ |
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456 | int FindNeighbors(VspBspNode *n, vector<VspBspLeaf *> &neighbors, |
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457 | const bool onlyUnmailed) const; |
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458 | |
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459 | /** Constructs geometry associated with the half space intersections |
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460 | leading to this node. |
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461 | */ |
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462 | void ConstructGeometry(VspBspNode *n, PolygonContainer &cell) const; |
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463 | |
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464 | /** Construct geometry and stores it in a geometry node container. |
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465 | */ |
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466 | void ConstructGeometry(VspBspNode *n, VspBspNodeGeometry &cell) const; |
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467 | |
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468 | /** Returns random leaf of BSP tree. |
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469 | @param halfspace defines the halfspace from which the leaf is taken. |
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470 | */ |
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471 | VspBspLeaf *GetRandomLeaf(const Plane3 &halfspace); |
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472 | |
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473 | /** Returns random leaf of BSP tree. |
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474 | @param onlyUnmailed if only unmailed leaves should be returned. |
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475 | */ |
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476 | VspBspLeaf *GetRandomLeaf(const bool onlyUnmailed = false); |
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477 | |
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478 | /** Returns true if merge criteria are reached. |
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479 | */ |
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480 | bool ShouldMerge(VspBspLeaf *front, VspBspLeaf *back) const; |
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481 | |
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482 | /** Merges view cells based on some criteria |
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483 | E.g., empty view cells can pe purged, view cells which have |
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484 | a very similar PVS can be merged to one larger view cell. |
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485 | |
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486 | @returns true if merge was successful. |
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487 | */ |
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488 | bool MergeViewCells(VspBspLeaf *front, VspBspLeaf *back) const; |
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489 | |
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490 | /** Traverses tree and counts all view cells as well as their PVS size. |
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491 | */ |
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492 | void EvaluateViewCellsStats(VspBspViewCellsStatistics &stat) const; |
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493 | |
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494 | |
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495 | protected: |
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496 | |
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497 | // -------------------------------------------------------------- |
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498 | // For sorting objects |
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499 | // -------------------------------------------------------------- |
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500 | struct SortableEntry |
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501 | { |
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502 | enum {POLY_MIN, POLY_MAX}; |
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503 | |
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504 | int type; |
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505 | float value; |
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506 | Polygon3 *poly; |
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507 | SortableEntry() {} |
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508 | SortableEntry(const int t, const float v, Polygon3 *poly): |
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509 | type(t), value(v), poly(poly) {} |
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510 | |
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511 | bool operator<(const SortableEntry &b) const |
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512 | { |
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513 | return value < b.value; |
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514 | } |
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515 | }; |
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516 | |
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517 | /** Evaluates tree stats in the BSP tree leafs. |
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518 | */ |
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519 | void EvaluateLeafStats(const VspBspTraversalData &data); |
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520 | |
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521 | /** Subdivides node with respect to the traversal data. |
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522 | @param tStack current traversal stack |
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523 | @param tData traversal data also holding node to be subdivided |
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524 | @returns new root of the subtree |
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525 | */ |
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526 | VspBspNode *Subdivide(VspBspTraversalStack &tStack, VspBspTraversalData &tData); |
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527 | |
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528 | /** Constructs the tree from the given list of polygons and rays. |
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529 | @param polys stores set of polygons on which subdivision may be based |
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530 | @param rays storesset of rays on which subdivision may be based |
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531 | */ |
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532 | void Construct(PolygonContainer *polys, RayInfoContainer *rays); |
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533 | |
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534 | /** Selects the best possible splitting plane. |
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535 | @param leaf the leaf to be split |
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536 | @param polys the polygon list on which the split decition is based |
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537 | @param rays ray container on which selection may be based |
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538 | @note the polygons can be reordered in the process |
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539 | @returns the split plane |
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540 | */ |
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541 | Plane3 SelectPlane(VspBspLeaf *leaf, |
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542 | VspBspTraversalData &data); |
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543 | |
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544 | |
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545 | /** Strategies where the effect of the split plane is tested |
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546 | on all input rays. |
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547 | |
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548 | @returns the cost of the candidate split plane |
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549 | */ |
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550 | float SplitPlaneCost(const Plane3 &candidatePlane, |
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551 | const VspBspTraversalData &data); |
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552 | |
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553 | |
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554 | |
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555 | /** Subdivide leaf. |
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556 | @param leaf the leaf to be subdivided |
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557 | |
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558 | @param polys the polygons to be split |
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559 | @param frontPolys returns the polygons in front of the split plane |
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560 | @param backPolys returns the polygons in the back of the split plane |
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561 | |
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562 | @param rays the polygons to be filtered |
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563 | @param frontRays returns the polygons in front of the split plane |
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564 | @param backRays returns the polygons in the back of the split plane |
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565 | |
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566 | @returns the root of the subdivision |
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567 | */ |
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568 | |
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569 | VspBspInterior *SubdivideNode(VspBspTraversalData &tData, |
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570 | VspBspTraversalData &frontData, |
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571 | VspBspTraversalData &backData, |
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572 | PolygonContainer &coincident); |
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573 | |
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574 | /** Selects the split plane in order to construct a tree with |
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575 | certain characteristics (e.g., balanced tree, least splits, |
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576 | 2.5d aligned) |
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577 | @param polygons container of polygons |
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578 | @param rays bundle of rays on which the split can be based |
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579 | */ |
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580 | Plane3 SelectPlaneHeuristics(VspBspLeaf *leaf, |
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581 | VspBspTraversalData &data); |
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582 | |
---|
583 | /** Extracts the meshes of the objects and adds them to polygons. |
---|
584 | Adds object aabb to the aabb of the tree. |
---|
585 | @param maxPolys the maximal number of objects to be stored as polygons |
---|
586 | @returns the number of polygons |
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587 | */ |
---|
588 | int AddToPolygonSoup(const ObjectContainer &objects, |
---|
589 | PolygonContainer &polys, |
---|
590 | int maxObjects = 0); |
---|
591 | |
---|
592 | /** Extracts the meshes of the view cells and and adds them to polygons. |
---|
593 | Adds view cell aabb to the aabb of the tree. |
---|
594 | @param maxPolys the maximal number of objects to be stored as polygons |
---|
595 | @returns the number of polygons |
---|
596 | */ |
---|
597 | int AddToPolygonSoup(const ViewCellContainer &viewCells, |
---|
598 | PolygonContainer &polys, |
---|
599 | int maxObjects = 0); |
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600 | |
---|
601 | /** Extract polygons of this mesh and add to polygon container. |
---|
602 | @param mesh the mesh that drives the polygon construction |
---|
603 | @param parent the parent intersectable this polygon is constructed from |
---|
604 | @returns number of polygons |
---|
605 | */ |
---|
606 | int AddMeshToPolygons(Mesh *mesh, PolygonContainer &polys, MeshInstance *parent); |
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607 | |
---|
608 | /** returns next candidate index and reorders polygons so no candidate is chosen two times |
---|
609 | @param the current candidate index |
---|
610 | @param max the range of candidates |
---|
611 | */ |
---|
612 | int GetNextCandidateIdx(int currentIdx, PolygonContainer &polys); |
---|
613 | |
---|
614 | /** Computes best cost ratio for the suface area heuristics for axis aligned |
---|
615 | splits. This heuristics minimizes the cost for ray traversal. |
---|
616 | @param polys the polygons guiding the ratio computation |
---|
617 | @param box the bounding box of the leaf |
---|
618 | @param axis the current split axis |
---|
619 | @param position returns the split position |
---|
620 | @param objectsBack the number of objects in the back of the split plane |
---|
621 | @param objectsFront the number of objects in the front of the split plane |
---|
622 | */ |
---|
623 | float BestCostRatio(const PolygonContainer &polys, |
---|
624 | const AxisAlignedBox3 &box, |
---|
625 | const int axis, |
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626 | float &position, |
---|
627 | int &objectsBack, |
---|
628 | int &objectsFront) const; |
---|
629 | |
---|
630 | /** Sorts split candidates for surface area heuristics for axis aligned splits. |
---|
631 | @param polys the input for choosing split candidates |
---|
632 | @param axis the current split axis |
---|
633 | @param splitCandidates returns sorted list of split candidates |
---|
634 | */ |
---|
635 | void SortSplitCandidates(const PolygonContainer &polys, |
---|
636 | const int axis, |
---|
637 | vector<SortableEntry> &splitCandidates) const; |
---|
638 | |
---|
639 | /** Selects an axis aligned split plane. |
---|
640 | Returns true if split is valied |
---|
641 | */ |
---|
642 | bool SelectAxisAlignedPlane(Plane3 &plane, const PolygonContainer &polys) const; |
---|
643 | |
---|
644 | /** Bounds ray and returns minT and maxT. |
---|
645 | @returns true if ray hits BSP tree bounding box |
---|
646 | */ |
---|
647 | bool BoundRay(const Ray &ray, float &minT, float &maxT) const; |
---|
648 | |
---|
649 | /** Subdivides the rays into front and back rays according to the split plane. |
---|
650 | |
---|
651 | @param plane the split plane |
---|
652 | @param rays contains the rays to be split. The rays are |
---|
653 | distributed into front and back rays. |
---|
654 | @param frontRays returns rays on the front side of the plane |
---|
655 | @param backRays returns rays on the back side of the plane |
---|
656 | |
---|
657 | @returns the number of splits |
---|
658 | */ |
---|
659 | int SplitRays(const Plane3 &plane, |
---|
660 | RayInfoContainer &rays, |
---|
661 | RayInfoContainer &frontRays, |
---|
662 | RayInfoContainer &backRays); |
---|
663 | |
---|
664 | |
---|
665 | /** Extracts the split planes representing the space bounded by node n. |
---|
666 | */ |
---|
667 | void ExtractHalfSpaces(VspBspNode *n, vector<Plane3> &halfSpaces) const; |
---|
668 | |
---|
669 | /** Adds the object to the pvs of the front and back leaf with a given classification. |
---|
670 | |
---|
671 | @param obj the object to be added |
---|
672 | @param cf the ray classification regarding the split plane |
---|
673 | @param frontPvs returns the PVS of the front partition |
---|
674 | @param backPvs returns the PVS of the back partition |
---|
675 | |
---|
676 | */ |
---|
677 | void AddObjToPvs(Intersectable *obj, const int cf, int &frontPvs, int &backPvs) const; |
---|
678 | |
---|
679 | /** Computes PVS size induced by the rays. |
---|
680 | */ |
---|
681 | int ComputePvsSize(const RayInfoContainer &rays) const; |
---|
682 | |
---|
683 | /** Returns true if tree can be terminated. |
---|
684 | */ |
---|
685 | inline bool TerminationCriteriaMet(const VspBspTraversalData &data) const; |
---|
686 | |
---|
687 | /** Computes accumulated ray lenght of this rays. |
---|
688 | */ |
---|
689 | float AccumulatedRayLength(const RayInfoContainer &rays) const; |
---|
690 | |
---|
691 | |
---|
692 | |
---|
693 | /// Pointer to the root of the tree |
---|
694 | VspBspNode *mRoot; |
---|
695 | |
---|
696 | VspBspTreeStatistics mStat; |
---|
697 | |
---|
698 | /// Strategies for choosing next split plane. |
---|
699 | enum {NO_STRATEGY = 0, |
---|
700 | RANDOM_POLYGON = 1, |
---|
701 | AXIS_ALIGNED = 2, |
---|
702 | LEAST_SPLITS = 4, |
---|
703 | BALANCED_POLYS = 8, |
---|
704 | BALANCED_VIEW_CELLS = 16, |
---|
705 | LARGEST_POLY_AREA = 32, |
---|
706 | VERTICAL_AXIS = 64, |
---|
707 | BLOCKED_RAYS = 128, |
---|
708 | LEAST_RAY_SPLITS = 256, |
---|
709 | BALANCED_RAYS = 512, |
---|
710 | PVS = 1024 |
---|
711 | }; |
---|
712 | |
---|
713 | /// box around the whole view domain |
---|
714 | AxisAlignedBox3 mBox; |
---|
715 | |
---|
716 | /// view cell corresponding to unbounded space |
---|
717 | BspViewCell *mRootCell; |
---|
718 | |
---|
719 | /// minimal number of rays before subdivision termination |
---|
720 | int mTermMinRays; |
---|
721 | /// maximal possible depth |
---|
722 | int mTermMaxDepth; |
---|
723 | /// mininum area |
---|
724 | float mTermMinArea; |
---|
725 | /// mininum PVS |
---|
726 | int mTermMinPvs; |
---|
727 | |
---|
728 | /// minimal number of rays for axis aligned split |
---|
729 | int mTermMinRaysForAxisAligned; |
---|
730 | /// minimal number of objects for axis aligned split |
---|
731 | int mTermMinObjectsForAxisAligned; |
---|
732 | /// maximal contribution per ray |
---|
733 | float mTermMaxRayContribution; |
---|
734 | /// minimal accumulated ray length |
---|
735 | float mTermMinAccRayLength; |
---|
736 | |
---|
737 | |
---|
738 | /// strategy to get the best split plane |
---|
739 | int mSplitPlaneStrategy; |
---|
740 | /// number of candidates evaluated for the next split plane |
---|
741 | int mMaxPolyCandidates; |
---|
742 | /// number of candidates for split planes evaluated using the rays |
---|
743 | int mMaxRayCandidates; |
---|
744 | |
---|
745 | float mCtDivCi; |
---|
746 | |
---|
747 | /// if intersected leaves should be stored with a sample |
---|
748 | bool mStoreLeavesWithRays; |
---|
749 | |
---|
750 | /// axis aligned split criteria |
---|
751 | float mAaCtDivCi; |
---|
752 | float mSplitBorder; |
---|
753 | float mMaxCostRatio; |
---|
754 | |
---|
755 | // factors guiding the split plane heuristics |
---|
756 | float mBlockedRaysFactor; |
---|
757 | float mLeastRaySplitsFactor; |
---|
758 | float mBalancedRaysFactor; |
---|
759 | float mPvsFactor; |
---|
760 | float mLeastSplitsFactor; |
---|
761 | |
---|
762 | //-- thresholds used for view cells merge |
---|
763 | int mMinPvsDif; |
---|
764 | int mMinPvs; |
---|
765 | int mMaxPvs; |
---|
766 | |
---|
767 | /// if area or accumulated ray lenght should be used for PVS heuristics |
---|
768 | bool mPvsUseArea; |
---|
769 | |
---|
770 | private: |
---|
771 | |
---|
772 | static const float sLeastRaySplitsTable[5]; |
---|
773 | /** Evaluates split plane classification with respect to the plane's |
---|
774 | contribution for balanced rays. |
---|
775 | */ |
---|
776 | static const float sBalancedRaysTable[5]; |
---|
777 | |
---|
778 | /// Generates unique ids for PVS criterium |
---|
779 | static void GenerateUniqueIdsForPvs(); |
---|
780 | |
---|
781 | //-- unique ids for PVS criterium |
---|
782 | static int sFrontId; |
---|
783 | static int sBackId; |
---|
784 | static int sFrontAndBackId; |
---|
785 | }; |
---|
786 | |
---|
787 | #endif |
---|