[162] | 1 | #include <stack> |
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| 2 | #include <algorithm> |
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| 3 | #include <queue> |
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| 4 | #include "Environment.h" |
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| 5 | #include "Mesh.h" |
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[65] | 6 | #include "KdTree.h" |
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| 7 | |
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[162] | 8 | |
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| 9 | |
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| 10 | |
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| 11 | KdNode::KdNode(KdInterior *parent):mParent(parent) |
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| 12 | { |
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| 13 | if (parent) |
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| 14 | mDepth = parent->mDepth+1; |
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| 15 | else |
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| 16 | mDepth = 0; |
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| 17 | } |
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| 18 | |
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| 19 | KdTree::KdTree() |
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| 20 | { |
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| 21 | mRoot = new KdLeaf(NULL, 0); |
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| 22 | environment->GetIntValue("KdTree.Termination.maxDepth", mTermMaxDepth); |
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| 23 | environment->GetIntValue("KdTree.Termination.minCost", mTermMinCost); |
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| 24 | environment->GetFloatValue("KdTree.Termination.maxCostRatio", mMaxCostRatio); |
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| 25 | environment->GetFloatValue("KdTree.Termination.ct_div_ci", mCt_div_ci); |
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| 26 | environment->GetFloatValue("KdTree.splitBorder", mSplitBorder); |
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| 27 | |
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[170] | 28 | environment->GetBoolValue("KdTree.sahUseFaces", mSahUseFaces); |
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| 29 | |
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[162] | 30 | char splitType[64]; |
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| 31 | environment->GetStringValue("KdTree.splitMethod", splitType); |
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[65] | 32 | |
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[162] | 33 | mSplitMethod = SPLIT_SPATIAL_MEDIAN; |
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| 34 | if (strcmp(splitType, "spatialMedian") == 0) |
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| 35 | mSplitMethod = SPLIT_SPATIAL_MEDIAN; |
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| 36 | else |
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| 37 | if (strcmp(splitType, "objectMedian") == 0) |
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| 38 | mSplitMethod = SPLIT_OBJECT_MEDIAN; |
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| 39 | else |
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| 40 | if (strcmp(splitType, "SAH") == 0) |
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| 41 | mSplitMethod = SPLIT_SAH; |
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| 42 | else { |
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| 43 | cerr<<"Wrong kd split type "<<splitType<<endl; |
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| 44 | exit(1); |
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| 45 | } |
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[170] | 46 | splitCandidates = NULL; |
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[162] | 47 | } |
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| 48 | |
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| 49 | bool |
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| 50 | KdTree::Construct() |
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| 51 | { |
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[170] | 52 | if (!splitCandidates) |
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| 53 | splitCandidates = new vector<SortableEntry>; |
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| 54 | |
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[162] | 55 | // first construct a leaf that will get subdivide |
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| 56 | KdLeaf *leaf = (KdLeaf *) mRoot; |
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| 57 | |
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| 58 | mStat.nodes = 1; |
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| 59 | |
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| 60 | mBox.Initialize(); |
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| 61 | |
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| 62 | MeshContainer::const_iterator mi; |
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| 63 | for ( mi = leaf->mObjects.begin(); |
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| 64 | mi != leaf->mObjects.end(); |
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| 65 | mi++) { |
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| 66 | mBox.Include((*mi)->GetBox()); |
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[65] | 67 | } |
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| 68 | |
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[170] | 69 | cout <<"KdTree Root Box:"<< mBox<<endl; |
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[162] | 70 | mRoot = Subdivide(TraversalData(leaf, mBox, 0)); |
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| 71 | |
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[170] | 72 | // remove the allocated array |
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| 73 | delete splitCandidates; |
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| 74 | |
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[162] | 75 | return true; |
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[65] | 76 | } |
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[162] | 77 | |
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| 78 | KdNode * |
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| 79 | KdTree::Subdivide(const TraversalData &tdata) |
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| 80 | { |
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| 81 | |
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| 82 | KdNode *result = NULL; |
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| 83 | |
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| 84 | priority_queue<TraversalData> tStack; |
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| 85 | // stack<STraversalData> tStack; |
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| 86 | |
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| 87 | tStack.push(tdata); |
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| 88 | AxisAlignedBox3 backBox, frontBox; |
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| 89 | |
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| 90 | |
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| 91 | while (!tStack.empty()) { |
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| 92 | |
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| 93 | #if 0 |
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| 94 | if ( GetMemUsage() > maxMemory ) { |
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| 95 | // count statistics on unprocessed leafs |
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| 96 | while (!tStack.empty()) { |
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| 97 | EvaluateLeafStats(tStack.top()); |
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| 98 | tStack.pop(); |
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| 99 | } |
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| 100 | break; |
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| 101 | } |
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| 102 | #endif |
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| 103 | |
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| 104 | TraversalData data = tStack.top(); |
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| 105 | tStack.pop(); |
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| 106 | |
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| 107 | KdNode *node = SubdivideNode((KdLeaf *) data.mNode, |
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| 108 | data.mBox, |
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| 109 | backBox, |
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| 110 | frontBox |
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| 111 | ); |
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| 112 | if (result == NULL) |
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| 113 | result = node; |
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| 114 | |
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| 115 | if (!node->IsLeaf()) { |
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| 116 | |
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| 117 | KdInterior *interior = (KdInterior *) node; |
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| 118 | // push the children on the stack |
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| 119 | tStack.push(TraversalData(interior->mBack, backBox, data.mDepth+1)); |
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| 120 | tStack.push(TraversalData(interior->mFront, frontBox, data.mDepth+1)); |
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| 121 | |
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| 122 | } else { |
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| 123 | EvaluateLeafStats(data); |
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| 124 | } |
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| 125 | } |
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| 126 | |
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| 127 | return result; |
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| 128 | |
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| 129 | } |
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| 130 | |
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| 131 | |
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| 132 | |
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| 133 | bool |
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| 134 | KdTree::TerminationCriteriaMet(const KdLeaf *leaf) |
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| 135 | { |
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| 136 | // cerr<<"\n OBJECTS="<<leaf->mObjects.size()<<endl; |
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| 137 | return |
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[170] | 138 | (leaf->mObjects.size() <= mTermMinCost) || |
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[162] | 139 | (leaf->mDepth >= mTermMaxDepth); |
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| 140 | |
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| 141 | } |
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| 142 | |
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| 143 | |
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| 144 | int |
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| 145 | KdTree::SelectPlane(KdLeaf *leaf, |
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| 146 | const AxisAlignedBox3 &box, |
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| 147 | float &position |
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| 148 | ) |
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| 149 | { |
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| 150 | int axis = -1; |
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| 151 | |
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| 152 | switch (mSplitMethod) |
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| 153 | { |
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| 154 | case SPLIT_SPATIAL_MEDIAN: { |
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| 155 | axis = box.Size().DrivingAxis(); |
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| 156 | position = (box.Min()[axis] + box.Max()[axis])*0.5f; |
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| 157 | break; |
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| 158 | } |
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| 159 | case SPLIT_SAH: { |
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| 160 | int objectsBack, objectsFront; |
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| 161 | float costRatio; |
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| 162 | bool mOnlyDrivingAxis = false; |
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| 163 | if (mOnlyDrivingAxis) { |
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| 164 | axis = box.Size().DrivingAxis(); |
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| 165 | costRatio = BestCostRatio(leaf, |
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| 166 | box, |
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| 167 | axis, |
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| 168 | position, |
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| 169 | objectsBack, |
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| 170 | objectsFront); |
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| 171 | } else { |
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| 172 | costRatio = MAX_FLOAT; |
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| 173 | for (int i=0; i < 3; i++) { |
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| 174 | float p; |
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| 175 | float r = BestCostRatio(leaf, |
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| 176 | box, |
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| 177 | i, |
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| 178 | p, |
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| 179 | objectsBack, |
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| 180 | objectsFront); |
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| 181 | if (r < costRatio) { |
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| 182 | costRatio = r; |
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| 183 | axis = i; |
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| 184 | position = p; |
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| 185 | } |
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| 186 | } |
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| 187 | } |
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| 188 | |
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| 189 | if (costRatio > mMaxCostRatio) { |
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| 190 | // cout<<"Too big cost ratio "<<costRatio<<endl; |
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| 191 | axis = -1; |
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| 192 | } |
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| 193 | break; |
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| 194 | } |
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| 195 | |
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| 196 | } |
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| 197 | return axis; |
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| 198 | } |
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| 199 | |
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| 200 | KdNode * |
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| 201 | KdTree::SubdivideNode( |
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| 202 | KdLeaf *leaf, |
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| 203 | const AxisAlignedBox3 &box, |
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| 204 | AxisAlignedBox3 &backBBox, |
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| 205 | AxisAlignedBox3 &frontBBox |
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| 206 | ) |
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| 207 | { |
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| 208 | |
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| 209 | if (TerminationCriteriaMet(leaf)) |
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| 210 | return leaf; |
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| 211 | |
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| 212 | float position; |
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| 213 | |
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| 214 | // select subdivision axis |
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| 215 | int axis = SelectPlane( leaf, box, position ); |
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| 216 | |
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| 217 | if (axis == -1) { |
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| 218 | return leaf; |
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| 219 | } |
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| 220 | |
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| 221 | mStat.nodes+=2; |
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| 222 | mStat.splits[axis]++; |
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| 223 | |
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| 224 | // add the new nodes to the tree |
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| 225 | KdInterior *node = new KdInterior(leaf->mParent); |
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| 226 | |
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| 227 | node->mAxis = axis; |
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| 228 | node->mPosition = position; |
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| 229 | node->mBox = box; |
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| 230 | |
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| 231 | backBBox = box; |
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| 232 | frontBBox = box; |
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| 233 | |
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| 234 | // first count ray sides |
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| 235 | int objectsBack = 0; |
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| 236 | int objectsFront = 0; |
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| 237 | |
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| 238 | backBBox.SetMax(axis, position); |
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| 239 | frontBBox.SetMin(axis, position); |
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| 240 | |
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| 241 | MeshContainer::const_iterator mi; |
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| 242 | |
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| 243 | for ( mi = leaf->mObjects.begin(); |
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| 244 | mi != leaf->mObjects.end(); |
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| 245 | mi++) { |
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| 246 | // determine the side of this ray with respect to the plane |
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| 247 | AxisAlignedBox3 box = (*mi)->GetBox(); |
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| 248 | if (box.Max(axis) > position ) |
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| 249 | objectsFront++; |
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| 250 | |
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| 251 | if (box.Min(axis) < position ) |
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| 252 | objectsBack++; |
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| 253 | } |
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| 254 | |
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| 255 | |
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| 256 | KdLeaf *back = new KdLeaf(node, objectsBack); |
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| 257 | KdLeaf *front = new KdLeaf(node, objectsFront); |
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| 258 | |
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| 259 | // replace a link from node's parent |
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| 260 | if ( leaf->mParent ) |
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| 261 | leaf->mParent->ReplaceChildLink(leaf, node); |
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| 262 | |
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| 263 | // and setup child links |
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| 264 | node->SetupChildLinks(back, front); |
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| 265 | |
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| 266 | for (mi = leaf->mObjects.begin(); |
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| 267 | mi != leaf->mObjects.end(); |
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| 268 | mi++) { |
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| 269 | // determine the side of this ray with respect to the plane |
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| 270 | AxisAlignedBox3 box = (*mi)->GetBox(); |
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| 271 | |
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| 272 | if (box.Max(axis) >= position ) |
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| 273 | front->mObjects.push_back(*mi); |
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| 274 | |
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| 275 | if (box.Min(axis) < position ) |
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| 276 | back->mObjects.push_back(*mi); |
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| 277 | |
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| 278 | mStat.objectRefs -= leaf->mObjects.size(); |
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| 279 | mStat.objectRefs += objectsBack + objectsFront; |
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| 280 | } |
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| 281 | |
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| 282 | delete leaf; |
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| 283 | return node; |
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| 284 | } |
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| 285 | |
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| 286 | |
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| 287 | |
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| 288 | void |
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| 289 | KdTreeStatistics::Print(ostream &app) const |
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| 290 | { |
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| 291 | app << "===== KdTree statistics ===============\n"; |
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| 292 | |
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| 293 | app << "#N_RAYS Number of rays )\n" |
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| 294 | << rays <<endl; |
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| 295 | app << "#N_DOMAINS ( Number of query domains )\n" |
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| 296 | << queryDomains <<endl; |
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| 297 | |
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| 298 | app << "#N_NODES ( Number of nodes )\n" << nodes << "\n"; |
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| 299 | |
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| 300 | app << "#N_LEAVES ( Number of leaves )\n" << Leaves() << "\n"; |
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| 301 | |
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| 302 | app << "#N_SPLITS ( Number of splits in axes x y z dx dy dz \n"; |
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| 303 | for (int i=0; i<7; i++) |
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| 304 | app << splits[i] <<" "; |
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| 305 | app <<endl; |
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| 306 | |
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| 307 | app << "#N_RAYREFS ( Number of rayRefs )\n" << |
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| 308 | rayRefs << "\n"; |
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| 309 | |
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| 310 | app << "#N_RAYRAYREFS ( Number of rayRefs / ray )\n" << |
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| 311 | rayRefs/(double)rays << "\n"; |
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| 312 | |
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| 313 | app << "#N_LEAFRAYREFS ( Number of rayRefs / leaf )\n" << |
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| 314 | rayRefs/(double)Leaves() << "\n"; |
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| 315 | |
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| 316 | app << "#N_MAXOBJECTREFS ( Max number of rayRefs / leaf )\n" << |
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| 317 | maxObjectRefs << "\n"; |
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| 318 | |
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| 319 | app << "#N_NONEMPTYRAYREFS ( Number of rayRefs in nonEmpty leaves / non empty leaf )\n" << |
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| 320 | rayRefsNonZeroQuery/(double)(Leaves() - zeroQueryNodes) << "\n"; |
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| 321 | |
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| 322 | app << "#N_LEAFDOMAINREFS ( Number of query domain Refs / leaf )\n" << |
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| 323 | objectRefs/(double)Leaves() << "\n"; |
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| 324 | |
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| 325 | // app << setprecision(4); |
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| 326 | |
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| 327 | app << "#N_PEMPTYLEAVES ( Percentage of leaves with zero query domains )\n"<< |
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| 328 | zeroQueryNodes*100/(double)Leaves()<<endl; |
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| 329 | |
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| 330 | app << "#N_PMAXDEPTHLEAVES ( Percentage of leaves at maxdepth )\n"<< |
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| 331 | maxDepthNodes*100/(double)Leaves()<<endl; |
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| 332 | |
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| 333 | app << "#N_PMINCOSTLEAVES ( Percentage of leaves with minCost )\n"<< |
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| 334 | minCostNodes*100/(double)Leaves()<<endl; |
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| 335 | |
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| 336 | app << "#N_ADDED_RAYREFS (Number of dynamically added ray references )\n"<< |
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| 337 | addedRayRefs<<endl; |
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| 338 | |
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| 339 | app << "#N_REMOVED_RAYREFS (Number of dynamically removed ray references )\n"<< |
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| 340 | removedRayRefs<<endl; |
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| 341 | |
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| 342 | // app << setprecision(4); |
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| 343 | |
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| 344 | // app << "#N_CTIME ( Construction time [s] )\n" |
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| 345 | // << Time() << " \n"; |
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| 346 | |
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| 347 | app << "===== END OF KdTree statistics ==========\n"; |
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| 348 | |
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| 349 | } |
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| 350 | |
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| 351 | |
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| 352 | |
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| 353 | void |
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| 354 | KdTree::EvaluateLeafStats(const TraversalData &data) |
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| 355 | { |
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| 356 | |
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| 357 | // the node became a leaf -> evaluate stats for leafs |
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| 358 | KdLeaf *leaf = (KdLeaf *)data.mNode; |
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| 359 | |
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| 360 | if (data.mDepth > mTermMaxDepth) |
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| 361 | mStat.maxDepthNodes++; |
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| 362 | |
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| 363 | if ( (int)(leaf->mObjects.size()) < mTermMinCost) |
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| 364 | mStat.minCostNodes++; |
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| 365 | |
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| 366 | |
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| 367 | if ( (int)(leaf->mObjects.size()) > mStat.maxObjectRefs) |
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| 368 | mStat.maxObjectRefs = leaf->mObjects.size(); |
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| 369 | |
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| 370 | } |
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| 371 | |
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| 372 | |
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| 373 | |
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| 374 | void |
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| 375 | KdTree::SortSplitCandidates( |
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| 376 | KdLeaf *node, |
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| 377 | const int axis |
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| 378 | ) |
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| 379 | { |
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| 380 | splitCandidates->clear(); |
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| 381 | |
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| 382 | int requestedSize = 2*node->mObjects.size(); |
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| 383 | // creates a sorted split candidates array |
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| 384 | if (splitCandidates->capacity() > 500000 && |
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| 385 | requestedSize < (int)(splitCandidates->capacity()/10) ) { |
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| 386 | delete splitCandidates; |
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| 387 | splitCandidates = new vector<SortableEntry>; |
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| 388 | } |
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| 389 | |
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| 390 | splitCandidates->reserve(requestedSize); |
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| 391 | |
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| 392 | // insert all queries |
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| 393 | for(MeshContainer::const_iterator mi = node->mObjects.begin(); |
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| 394 | mi < node->mObjects.end(); |
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| 395 | mi++) { |
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| 396 | AxisAlignedBox3 box = (*mi)->GetBox(); |
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| 397 | |
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| 398 | splitCandidates->push_back(SortableEntry(SortableEntry::MESH_MIN, |
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| 399 | box.Min(axis), |
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| 400 | (void *)*mi) |
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| 401 | ); |
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| 402 | |
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| 403 | |
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| 404 | splitCandidates->push_back(SortableEntry(SortableEntry::MESH_MAX, |
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| 405 | box.Max(axis), |
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| 406 | (void *)*mi) |
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| 407 | ); |
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| 408 | } |
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| 409 | |
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| 410 | stable_sort(splitCandidates->begin(), splitCandidates->end()); |
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| 411 | } |
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| 412 | |
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| 413 | |
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| 414 | float |
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| 415 | KdTree::BestCostRatio( |
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| 416 | KdLeaf *node, |
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| 417 | const AxisAlignedBox3 &box, |
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| 418 | const int axis, |
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| 419 | float &position, |
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| 420 | int &objectsBack, |
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| 421 | int &objectsFront |
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| 422 | ) |
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| 423 | { |
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| 424 | |
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| 425 | SortSplitCandidates(node, axis); |
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| 426 | |
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| 427 | // go through the lists, count the number of objects left and right |
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| 428 | // and evaluate the following cost funcion: |
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| 429 | // C = ct_div_ci + (ol + or)/queries |
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| 430 | |
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[170] | 431 | int totalFaces = 0; |
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| 432 | vector<SortableEntry>::const_iterator ci; |
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| 433 | |
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| 434 | for(ci = splitCandidates->begin(); |
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| 435 | ci < splitCandidates->end(); |
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| 436 | ci++) |
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| 437 | if ((*ci).type == SortableEntry::MESH_MIN) { |
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| 438 | Mesh *mesh = ((MeshInstance *)(*ci).data)->GetMesh(); |
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| 439 | totalFaces += mesh->mFaces.size(); |
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| 440 | } |
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| 441 | |
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| 442 | int facesLeft = 0; |
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| 443 | int facesRight = totalFaces; |
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| 444 | |
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[165] | 445 | int objectsLeft = 0, objectsRight = node->mObjects.size(); |
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[170] | 446 | |
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[162] | 447 | float minBox = box.Min(axis); |
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| 448 | float maxBox = box.Max(axis); |
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| 449 | float boxArea = box.SurfaceArea(); |
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| 450 | |
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| 451 | float minBand = minBox + mSplitBorder*(maxBox - minBox); |
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| 452 | float maxBand = minBox + (1.0f - mSplitBorder)*(maxBox - minBox); |
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| 453 | |
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| 454 | float minSum = 1e20; |
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| 455 | |
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[170] | 456 | for(ci = splitCandidates->begin(); |
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[162] | 457 | ci < splitCandidates->end(); |
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| 458 | ci++) { |
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[170] | 459 | Mesh *mesh = ((MeshInstance *)(*ci).data)->GetMesh(); |
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[162] | 460 | switch ((*ci).type) { |
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| 461 | case SortableEntry::MESH_MIN: |
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[165] | 462 | objectsLeft++; |
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[170] | 463 | facesLeft += mesh->mFaces.size(); |
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[162] | 464 | break; |
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| 465 | case SortableEntry::MESH_MAX: |
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[165] | 466 | objectsRight--; |
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[170] | 467 | facesRight -= mesh->mFaces.size(); |
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[162] | 468 | break; |
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| 469 | } |
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| 470 | |
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| 471 | if ((*ci).value > minBand && (*ci).value < maxBand) { |
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| 472 | AxisAlignedBox3 lbox = box; |
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| 473 | AxisAlignedBox3 rbox = box; |
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| 474 | lbox.SetMax(axis, (*ci).value); |
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| 475 | rbox.SetMin(axis, (*ci).value); |
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| 476 | |
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[170] | 477 | float sum; |
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| 478 | if (mSahUseFaces) |
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| 479 | sum = facesLeft*lbox.SurfaceArea() + facesRight*rbox.SurfaceArea(); |
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| 480 | else |
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| 481 | sum = objectsLeft*lbox.SurfaceArea() + objectsRight*rbox.SurfaceArea(); |
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[162] | 482 | |
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| 483 | // cout<<"pos="<<(*ci).value<<"\t q=("<<ql<<","<<qr<<")\t r=("<<rl<<","<<rr<<")"<<endl; |
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| 484 | // cout<<"cost= "<<sum<<endl; |
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| 485 | |
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| 486 | if (sum < minSum) { |
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| 487 | minSum = sum; |
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| 488 | position = (*ci).value; |
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| 489 | |
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[165] | 490 | objectsBack = objectsLeft; |
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| 491 | objectsFront = objectsRight; |
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[162] | 492 | } |
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| 493 | } |
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| 494 | } |
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| 495 | |
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[170] | 496 | float oldCost = mSahUseFaces ? totalFaces : node->mObjects.size(); |
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[162] | 497 | float newCost = mCt_div_ci + minSum/boxArea; |
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| 498 | float ratio = newCost/oldCost; |
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[170] | 499 | |
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[162] | 500 | #if 0 |
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| 501 | cout<<"===================="<<endl; |
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| 502 | cout<<"costRatio="<<ratio<<" pos="<<position<<" t="<<(position - minBox)/(maxBox - minBox) |
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| 503 | <<"\t o=("<<objectsBack<<","<<objectsFront<<")"<<endl; |
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| 504 | #endif |
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| 505 | return ratio; |
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| 506 | } |
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| 507 | |
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| 508 | int |
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| 509 | KdTree::CastRay( |
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| 510 | Ray &ray |
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| 511 | ) |
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| 512 | { |
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| 513 | int hits = 0; |
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| 514 | |
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| 515 | stack<RayTraversalData> tStack; |
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| 516 | |
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| 517 | float maxt = 1e6; |
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| 518 | float mint = 0; |
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| 519 | |
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| 520 | |
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| 521 | if (!mBox.GetMinMaxT(ray, &mint, &maxt)) |
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| 522 | return 0; |
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| 523 | |
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| 524 | if (mint < 0) |
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| 525 | mint = 0; |
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| 526 | |
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| 527 | maxt += Limits::Threshold; |
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| 528 | |
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| 529 | Vector3 entp = ray.Extrap(mint); |
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| 530 | Vector3 extp = ray.Extrap(maxt); |
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| 531 | |
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| 532 | KdNode *node = mRoot; |
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| 533 | KdNode *farChild; |
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| 534 | float position; |
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| 535 | int axis; |
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| 536 | |
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| 537 | while (1) { |
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| 538 | if (!node->IsLeaf()) { |
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| 539 | KdInterior *in = (KdInterior *) node; |
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| 540 | position = in->mPosition; |
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| 541 | axis = in->mAxis; |
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| 542 | |
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| 543 | if (entp[axis] <= position) { |
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| 544 | if (extp[axis] <= position) { |
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| 545 | node = in->mBack; |
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| 546 | // cases N1,N2,N3,P5,Z2,Z3 |
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| 547 | continue; |
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| 548 | } else { |
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| 549 | // case N4 |
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| 550 | node = in->mBack; |
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| 551 | farChild = in->mFront; |
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| 552 | } |
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| 553 | } |
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| 554 | else { |
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| 555 | if (position <= extp[axis]) { |
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| 556 | node = in->mFront; |
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| 557 | // cases P1,P2,P3,N5,Z1 |
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| 558 | continue; |
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| 559 | } else { |
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| 560 | node = in->mFront; |
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| 561 | farChild = in->mBack; |
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| 562 | // case P4 |
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| 563 | } |
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| 564 | } |
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| 565 | // $$ modification 3.5.2004 - hints from Kamil Ghais |
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| 566 | // case N4 or P4 |
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| 567 | float tdist = (position - ray.GetLoc(axis)) / ray.GetDir(axis); |
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| 568 | tStack.push(RayTraversalData(farChild, extp, maxt)); |
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| 569 | extp = ray.GetLoc() + ray.GetDir()*tdist; |
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| 570 | maxt = tdist; |
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| 571 | } else { |
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| 572 | // compute intersection with all objects in this leaf |
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| 573 | KdLeaf *leaf = (KdLeaf *) node; |
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| 574 | ray.leaves.push_back(leaf); |
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| 575 | |
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| 576 | MeshContainer::const_iterator mi; |
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| 577 | for ( mi = leaf->mObjects.begin(); |
---|
| 578 | mi != leaf->mObjects.end(); |
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| 579 | mi++) { |
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| 580 | MeshInstance *mesh = *mi; |
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| 581 | if (!mesh->Mailed() ) { |
---|
| 582 | mesh->Mail(); |
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| 583 | //ray.meshes.push_back(mesh); |
---|
| 584 | hits += mesh->CastRay(ray); |
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| 585 | } |
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| 586 | } |
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| 587 | |
---|
| 588 | if (hits && ray.GetType() == Ray::LOCAL_RAY) |
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| 589 | if (ray.intersections[0].mT <= maxt) |
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| 590 | break; |
---|
| 591 | |
---|
| 592 | // get the next node from the stack |
---|
| 593 | if (tStack.empty()) |
---|
| 594 | break; |
---|
| 595 | |
---|
| 596 | entp = extp; |
---|
| 597 | mint = maxt; |
---|
| 598 | RayTraversalData &s = tStack.top(); |
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| 599 | node = s.mNode; |
---|
| 600 | extp = s.mExitPoint; |
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| 601 | maxt = s.mMaxT; |
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| 602 | tStack.pop(); |
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| 603 | } |
---|
| 604 | } |
---|
| 605 | |
---|
| 606 | |
---|
| 607 | return hits; |
---|
| 608 | } |
---|
| 609 | |
---|