[221] | 1 | #ifndef _ViewCellBsp_H__ |
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| 2 | #define _ViewCellBsp_H__ |
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| 3 | |
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| 4 | #include "Mesh.h" |
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[224] | 5 | #include "Containers.h" |
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[233] | 6 | #include <stack> |
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[224] | 7 | |
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[221] | 8 | class ViewCell; |
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| 9 | class Plane3; |
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[224] | 10 | class BspTree; |
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[221] | 11 | class BspInterior; |
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[235] | 12 | class Polygon3; |
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[242] | 13 | class AxisAlignedBox3; |
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[260] | 14 | class Ray; |
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[221] | 15 | |
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[241] | 16 | struct BspRayTraversalData |
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| 17 | { |
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| 18 | BspNode *mNode; |
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| 19 | Vector3 mExitPoint; |
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| 20 | float mMaxT; |
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| 21 | |
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| 22 | BspRayTraversalData() {} |
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| 23 | |
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[313] | 24 | BspRayTraversalData(BspNode *n, const Vector3 &extp, const float maxt): |
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| 25 | mNode(n), mExitPoint(extp), mMaxT(maxt) |
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[241] | 26 | {} |
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| 27 | }; |
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| 28 | |
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[322] | 29 | class BspTreeStatistics |
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[234] | 30 | { |
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| 31 | public: |
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| 32 | // total number of nodes |
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| 33 | int nodes; |
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[235] | 34 | // number of splits |
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| 35 | int splits; |
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[234] | 36 | // totals number of rays |
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| 37 | int rays; |
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[235] | 38 | // maximal reached depth |
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| 39 | int maxDepth; |
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[265] | 40 | // minimal depth |
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| 41 | int minDepth; |
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[234] | 42 | // max depth nodes |
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| 43 | int maxDepthNodes; |
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| 44 | // max number of rays per node |
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| 45 | int maxObjectRefs; |
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[322] | 46 | // accumulated depth (used to compute average) |
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[265] | 47 | int accumDepth; |
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| 48 | // number of initial polygons |
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| 49 | int polys; |
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[322] | 50 | /// number of view cells different to the view cell representing unbounded space. |
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| 51 | int viewCells; |
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[332] | 52 | /// size of the VPS |
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| 53 | int pvs; |
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| 54 | /// samples contributing to pvs |
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| 55 | int contributingSamples; |
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[350] | 56 | /// sample contributions to pvs |
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| 57 | int sampleContributions; |
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| 58 | |
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[234] | 59 | // Constructor |
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| 60 | BspTreeStatistics() |
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| 61 | { |
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[235] | 62 | Reset(); |
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[234] | 63 | } |
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| 64 | |
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| 65 | int Nodes() const {return nodes;} |
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[263] | 66 | int Interior() const { return nodes / 2; } |
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| 67 | int Leaves() const { return (nodes / 2) + 1; } |
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[271] | 68 | double AvgDepth() const { return accumDepth / (double)Leaves();}; // TODO: computation wrong |
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[265] | 69 | |
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[234] | 70 | void Reset() |
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| 71 | { |
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| 72 | nodes = 0; |
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[235] | 73 | splits = 0; |
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[234] | 74 | maxDepthNodes = 0; |
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[265] | 75 | maxDepth = 0; |
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| 76 | minDepth = 99999; |
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| 77 | polys = 0; |
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| 78 | accumDepth = 0; |
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[322] | 79 | viewCells = 0; |
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[332] | 80 | pvs = 0; |
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| 81 | contributingSamples = 0; |
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[350] | 82 | sampleContributions = 0; |
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[234] | 83 | } |
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| 84 | |
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| 85 | void |
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| 86 | Print(ostream &app) const; |
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| 87 | |
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| 88 | friend ostream &operator<<(ostream &s, const BspTreeStatistics &stat) { |
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| 89 | stat.Print(s); |
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| 90 | return s; |
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| 91 | } |
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| 92 | |
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| 93 | }; |
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| 94 | |
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[233] | 95 | /** |
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| 96 | BspNode abstract class serving for interior and leaf node implementation |
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| 97 | */ |
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| 98 | class BspNode |
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| 99 | { |
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| 100 | friend BspTree; |
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[221] | 101 | |
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[233] | 102 | public: |
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[235] | 103 | BspNode(); |
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[264] | 104 | virtual ~BspNode(); |
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[235] | 105 | BspNode(BspInterior *parent); |
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| 106 | |
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[233] | 107 | /** Determines whether this node is a leaf or not |
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| 108 | @return true if leaf |
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| 109 | */ |
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| 110 | virtual bool IsLeaf() const = 0; |
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[221] | 111 | |
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[233] | 112 | /** Determines whether this node is a root |
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| 113 | @return true if root |
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| 114 | */ |
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| 115 | virtual bool IsRoot() const; |
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[221] | 116 | |
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[233] | 117 | /** Returns parent node. |
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| 118 | */ |
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| 119 | BspInterior *GetParent(); |
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[235] | 120 | /** Sets parent node. |
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| 121 | */ |
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| 122 | void SetParent(BspInterior *parent); |
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| 123 | |
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[264] | 124 | /** Returns pointer to polygons. |
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| 125 | */ |
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[260] | 126 | PolygonContainer *GetPolygons(); |
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[286] | 127 | /** Stores polygons in node or discards them according to storePolys. |
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[263] | 128 | */ |
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[264] | 129 | void ProcessPolygons(PolygonContainer *polys, const bool storePolys); |
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[263] | 130 | |
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[286] | 131 | //int mViewCellIdx; |
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| 132 | protected: |
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[221] | 133 | |
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[233] | 134 | /// parent of this node |
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| 135 | BspInterior *mParent; |
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[260] | 136 | |
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[264] | 137 | /// store polygons created during BSP splits |
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| 138 | PolygonContainer *mPolygons; |
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[233] | 139 | }; |
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[221] | 140 | |
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[233] | 141 | /** BSP interior node implementation |
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| 142 | */ |
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| 143 | class BspInterior : public BspNode |
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| 144 | { |
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[297] | 145 | friend BspTree; |
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[233] | 146 | public: |
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| 147 | /** Standard contructor taking split plane as argument. |
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| 148 | */ |
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[263] | 149 | BspInterior(const Plane3 &plane); |
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[233] | 150 | /** @return false since it is an interior node |
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| 151 | */ |
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| 152 | bool IsLeaf() const; |
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[222] | 153 | |
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[233] | 154 | BspNode *GetBack(); |
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| 155 | BspNode *GetFront(); |
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[221] | 156 | |
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[233] | 157 | Plane3 *GetPlane(); |
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[221] | 158 | |
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[233] | 159 | void ReplaceChildLink(BspNode *oldChild, BspNode *newChild); |
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| 160 | void SetupChildLinks(BspNode *b, BspNode *f); |
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[225] | 161 | |
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[318] | 162 | /** Splits polygons with respect to the split plane. |
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| 163 | @param polys the polygons to be split. the polygons are consumed and |
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| 164 | distributed to the containers frontPolys, backPolys, coincident. |
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[233] | 165 | @param frontPolys returns the polygons in the front of the split plane |
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| 166 | @param backPolys returns the polygons in the back of the split plane |
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[289] | 167 | @param coincident returns the polygons coincident to the split plane |
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| 168 | @param storePolys if the polygons should be stored in the node |
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[328] | 169 | @returns the number of splits |
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[233] | 170 | */ |
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[328] | 171 | int SplitPolygons(PolygonContainer &polys, |
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| 172 | PolygonContainer &frontPolys, |
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| 173 | PolygonContainer &backPolys, |
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| 174 | PolygonContainer &coincident, |
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[349] | 175 | const bool storePolys = false); |
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[225] | 176 | |
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[286] | 177 | /** Stores polygon in node or discards them according to storePolys. |
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| 178 | @param polys the polygons |
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| 179 | @param storePolys if the polygons should be stored or discarded |
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| 180 | */ |
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[289] | 181 | void ProcessPolygon(Polygon3 **poly, const bool storePolys); |
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[286] | 182 | |
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[237] | 183 | friend ostream &operator<<(ostream &s, const BspInterior &A) |
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| 184 | { |
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| 185 | return s << A.mPlane; |
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| 186 | } |
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| 187 | |
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[349] | 188 | protected: |
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[328] | 189 | |
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[233] | 190 | /// Splitting plane corresponding to this node |
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| 191 | Plane3 mPlane; |
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| 192 | /// back node |
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| 193 | BspNode *mBack; |
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| 194 | /// front node |
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| 195 | BspNode *mFront; |
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| 196 | }; |
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[225] | 197 | |
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[237] | 198 | /** BSP leaf node implementation. |
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| 199 | */ |
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[233] | 200 | class BspLeaf : public BspNode |
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| 201 | { |
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[260] | 202 | friend BspTree; |
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| 203 | |
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[233] | 204 | public: |
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[263] | 205 | BspLeaf(); |
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| 206 | BspLeaf(ViewCell *viewCell); |
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| 207 | BspLeaf(BspInterior *parent); |
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[264] | 208 | BspLeaf(BspInterior *parent, ViewCell *viewCell); |
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[225] | 209 | |
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[260] | 210 | /** @return true since it is an interior node |
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| 211 | */ |
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[233] | 212 | bool IsLeaf() const; |
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[260] | 213 | /** Returns pointer from view cell. |
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| 214 | */ |
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[233] | 215 | ViewCell *GetViewCell(); |
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[260] | 216 | /** Sets pointer to view cell. |
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| 217 | */ |
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| 218 | void SetViewCell(ViewCell *viewCell); |
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[225] | 219 | |
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[332] | 220 | /** Generates new view cell and adds rays to the PVS. |
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[350] | 221 | @param sampleContributions the number contributions of the sampels |
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| 222 | @param contributingSampels the number of contributing rays |
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[352] | 223 | @param storeRays if ray set should be stored in view cell |
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[331] | 224 | */ |
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[350] | 225 | void BspLeaf::GenerateViewCell(const RayContainer &rays, |
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| 226 | int &sampleContributions, |
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[352] | 227 | int &contributingSamples, |
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| 228 | const bool storeRays = false); |
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[331] | 229 | |
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[233] | 230 | protected: |
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[225] | 231 | |
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[313] | 232 | /// if NULL this does not correspond to feasible viewcell |
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[233] | 233 | ViewCell *mViewCell; |
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| 234 | }; |
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[225] | 235 | |
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[310] | 236 | /** Implementation of the view cell BSP tree. |
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| 237 | */ |
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[233] | 238 | class BspTree |
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| 239 | { |
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| 240 | public: |
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| 241 | |
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| 242 | /** Additional data which is passed down the BSP tree during traversal. |
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| 243 | */ |
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| 244 | struct BspTraversalData |
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| 245 | { |
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| 246 | /// the current node |
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| 247 | BspNode *mNode; |
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| 248 | /// polygonal data for splitting |
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[238] | 249 | PolygonContainer *mPolygons; |
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[233] | 250 | /// current depth |
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| 251 | int mDepth; |
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[289] | 252 | /// the view cell associated with this subdivsion |
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| 253 | ViewCell *mViewCell; |
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[325] | 254 | /// rays piercing this node |
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| 255 | RayContainer *mRays; |
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| 256 | |
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[318] | 257 | BspTraversalData(): |
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| 258 | mNode(NULL), |
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| 259 | mPolygons(NULL), |
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| 260 | mDepth(0), |
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[325] | 261 | mViewCell(NULL), |
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| 262 | mRays(NULL) |
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[318] | 263 | {} |
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[233] | 264 | |
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[318] | 265 | BspTraversalData(BspNode *node, |
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| 266 | PolygonContainer *polys, |
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| 267 | const int depth, |
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[325] | 268 | ViewCell *viewCell, |
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[328] | 269 | RayContainer *rays): |
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[318] | 270 | mNode(node), |
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| 271 | mPolygons(polys), |
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| 272 | mDepth(depth), |
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[325] | 273 | mViewCell(viewCell), |
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| 274 | mRays(rays) |
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[318] | 275 | {} |
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[233] | 276 | }; |
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[329] | 277 | |
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[233] | 278 | typedef std::stack<BspTraversalData> BspTraversalStack; |
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| 279 | |
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[235] | 280 | /** Default constructor creating an empty tree. |
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[297] | 281 | @param viewCell view cell corresponding to unbounded space |
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[233] | 282 | */ |
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[297] | 283 | BspTree(ViewCell *viewCell); |
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[233] | 284 | |
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| 285 | ~BspTree(); |
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| 286 | |
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[235] | 287 | const BspTreeStatistics &GetStatistics() const; |
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| 288 | |
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[303] | 289 | /** Constructs tree using the given list of view cells. |
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[289] | 290 | For this type of construction we filter all view cells down the |
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| 291 | tree. If there is no polygon left, the last split plane |
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[303] | 292 | decides inside or outside of the viewcell. A pointer to the |
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| 293 | appropriate view cell is stored within each leaf. |
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| 294 | Many leafs can point to the same viewcell. |
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| 295 | */ |
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[332] | 296 | void Construct(const ViewCellContainer &viewCells); |
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[303] | 297 | |
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| 298 | /** Constructs tree using the given list of objects. |
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[319] | 299 | @note the objects are not taken as view cells, but the view cells are |
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| 300 | constructed from the subdivision: Each leaf is taken as one viewcell. |
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[303] | 301 | @param objects list of objects |
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| 302 | */ |
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[332] | 303 | void Construct(const ObjectContainer &objects); |
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[235] | 304 | |
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[331] | 305 | /** Constructs the tree from a given set of rays. |
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| 306 | @param sampleRays the set of sample rays the construction is based on |
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[319] | 307 | @param viewCells if not NULL, new view cells are |
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| 308 | created in the leafs and stored in the conatainer |
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| 309 | */ |
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[332] | 310 | void Construct(const RayContainer &sampleRays); |
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[260] | 311 | |
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[319] | 312 | /** Returns list of BSP leaves. |
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| 313 | */ |
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[240] | 314 | void CollectLeaves(vector<BspLeaf *> &leaves); |
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| 315 | |
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[242] | 316 | /** Returns box which bounds the whole tree. |
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| 317 | */ |
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| 318 | AxisAlignedBox3 GetBoundingBox()const; |
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| 319 | |
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| 320 | /** Returns root of BSP tree. |
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| 321 | */ |
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| 322 | BspNode *GetRoot() const; |
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| 323 | |
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[262] | 324 | /** Exports Bsp tree to file. |
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| 325 | */ |
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| 326 | bool Export(const string filename); |
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| 327 | |
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[332] | 328 | /** Collects the leaf view cells of the tree |
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| 329 | @param viewCells returns the view cells |
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| 330 | */ |
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| 331 | void CollectViewCells(ViewCellContainer &viewCells) const; |
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[308] | 332 | |
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| 333 | /** A ray is cast possible intersecting the tree. |
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| 334 | @param the ray that is cast. |
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| 335 | @returns the number of intersections with objects stored in the tree. |
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| 336 | */ |
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| 337 | int CastRay(Ray &ray); |
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| 338 | |
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[341] | 339 | /** Merges view cells based on some criteria |
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| 340 | E.g., empty view cells can pe purged, view cells which have |
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| 341 | a very similar PVS can be merged to one larger view cell farther up |
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| 342 | in the BSP tree. |
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[338] | 343 | @returns the number of merged view cells |
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[332] | 344 | */ |
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[342] | 345 | int MergeViewCells(); |
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[338] | 346 | |
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| 347 | /** Set to true if new view cells shall be generated in each leaf. |
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| 348 | */ |
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[332] | 349 | void SetGenerateViewCells(int generateViewCells); |
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| 350 | |
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[310] | 351 | /// bsp tree construction types |
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| 352 | enum {FROM_INPUT_VIEW_CELLS, FROM_SCENE_GEOMETRY, FROM_RAYS}; |
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| 353 | |
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[332] | 354 | /** Returns statistics. |
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| 355 | */ |
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| 356 | BspTreeStatistics &GetStat(); |
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| 357 | |
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[233] | 358 | protected: |
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[342] | 359 | |
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[303] | 360 | // -------------------------------------------------------------- |
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| 361 | // For sorting objects |
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| 362 | // -------------------------------------------------------------- |
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| 363 | struct SortableEntry |
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| 364 | { |
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| 365 | enum {POLY_MIN, POLY_MAX}; |
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| 366 | |
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| 367 | int type; |
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| 368 | float value; |
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| 369 | Polygon3 *poly; |
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| 370 | SortableEntry() {} |
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| 371 | SortableEntry(const int t, const float v, Polygon3 *poly): |
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| 372 | type(t), value(v), poly(poly) {} |
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| 373 | |
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| 374 | bool operator<(const SortableEntry &b) const |
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| 375 | { |
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| 376 | return value < b.value; |
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| 377 | } |
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[302] | 378 | }; |
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| 379 | |
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[352] | 380 | /** Merges view cells of leafs. |
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| 381 | */ |
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| 382 | void MergeLeafs(BspLeaf *front, BspLeaf *back) const; |
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[238] | 383 | |
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| 384 | /** Evaluates tree stats in the BSP tree leafs. |
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| 385 | */ |
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[235] | 386 | void EvaluateLeafStats(const BspTraversalData &data); |
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| 387 | |
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| 388 | /** Subdivides node with respect to the traversal data. |
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| 389 | @param tStack current traversal stack |
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| 390 | @param tData traversal data also holding node to be subdivided |
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[239] | 391 | @returns new root of the subtree |
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[233] | 392 | */ |
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[308] | 393 | BspNode *Subdivide(BspTraversalStack &tStack, BspTraversalData &tData); |
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[233] | 394 | |
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[332] | 395 | /** Constructs the tree from the given list of polygons and rays. |
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| 396 | @param polys stores set of polygons on which subdivision may be based |
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| 397 | @param rays storesset of rays on which subdivision may be based |
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[327] | 398 | */ |
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[332] | 399 | void Construct(PolygonContainer *polys, RayContainer *rays); |
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[327] | 400 | |
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[319] | 401 | /** Selects the best possible splitting plane. |
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[302] | 402 | @param leaf the leaf to be split |
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[263] | 403 | @param polys the polygon list on which the split decition is based |
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[325] | 404 | @param rays ray container on which selection may be based |
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[335] | 405 | @note the polygons can be reordered in the process |
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| 406 | @returns the split plane |
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[233] | 407 | */ |
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[318] | 408 | Plane3 SelectPlane(BspLeaf *leaf, |
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[325] | 409 | PolygonContainer &polys, |
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| 410 | const RayContainer &ray); |
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[303] | 411 | |
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[327] | 412 | /** Evaluates the contribution of the candidate split plane. |
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[335] | 413 | |
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| 414 | @param canditatePlane the candidate split plane |
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| 415 | @param polys the polygons the split can be based on |
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| 416 | @param rays the rays the split can be based on |
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[327] | 417 | @returns the cost of the candidate split plane |
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| 418 | */ |
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[335] | 419 | float SplitPlaneCost(const Plane3 &candidatePlane, |
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| 420 | const PolygonContainer &polys, |
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| 421 | const RayContainer &rays) const; |
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[327] | 422 | |
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[335] | 423 | /** Strategies where the effect of the split plane is tested |
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| 424 | on all input rays. |
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| 425 | @returns the cost of the candidate split plane |
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| 426 | */ |
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| 427 | float SplitPlaneCost(const Plane3 &candidatePlane, |
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| 428 | const PolygonContainer &polys) const; |
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| 429 | |
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| 430 | /** Strategies where the effect of the split plane is tested |
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| 431 | on all input polygons. |
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| 432 | @returns the cost of the candidate split plane |
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| 433 | */ |
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| 434 | float SplitPlaneCost(const Plane3 &candidatePlane, |
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| 435 | const RayContainer &polys) const; |
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| 436 | |
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[303] | 437 | /** Filters next view cell down the tree and inserts it into the appropriate leaves |
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| 438 | (i.e., possibly more than one leaf). |
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| 439 | */ |
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[289] | 440 | void InsertViewCell(ViewCell *viewCell); |
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[303] | 441 | /** Inserts polygons down the tree. The polygons are filtered until a leaf is reached, |
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| 442 | then further subdivided. |
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| 443 | */ |
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[332] | 444 | void InsertPolygons(PolygonContainer *polys); |
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[303] | 445 | |
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| 446 | /** Subdivide leaf. |
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| 447 | @param leaf the leaf to be subdivided |
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[329] | 448 | |
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| 449 | @param polys the polygons to be split |
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| 450 | @param frontPolys returns the polygons in front of the split plane |
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| 451 | @param backPolys returns the polygons in the back of the split plane |
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| 452 | |
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| 453 | @param rays the polygons to be filtered |
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| 454 | @param frontRays returns the polygons in front of the split plane |
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| 455 | @param backRays returns the polygons in the back of the split plane |
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| 456 | |
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[303] | 457 | @returns the root of the subdivision |
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| 458 | */ |
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| 459 | BspInterior *SubdivideNode(BspLeaf *leaf, |
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[329] | 460 | PolygonContainer &polys, |
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| 461 | PolygonContainer &frontPolys, |
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| 462 | PolygonContainer &backPolys, |
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| 463 | PolygonContainer &coincident, |
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| 464 | RayContainer &rays, |
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[349] | 465 | RayContainer &frontRays, |
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| 466 | RayContainer &backRays); |
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[221] | 467 | |
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[233] | 468 | /** Filters polygons down the tree. |
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| 469 | @param node the current BSP node |
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| 470 | @param polys the polygons to be filtered |
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| 471 | @param frontPolys returns the polygons in front of the split plane |
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| 472 | @param backPolys returns the polygons in the back of the split plane |
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| 473 | */ |
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[319] | 474 | void FilterPolygons(BspInterior *node, |
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| 475 | PolygonContainer *polys, |
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| 476 | PolygonContainer *frontPolys, |
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| 477 | PolygonContainer *backPolys); |
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[224] | 478 | |
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[318] | 479 | /** Selects the split plane in order to construct a tree with |
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| 480 | certain characteristics (e.g., balanced tree, least splits, |
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| 481 | 2.5d aligned) |
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[238] | 482 | @param polygons container of polygons |
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[325] | 483 | @param rays bundle of rays on which the split can be based |
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[238] | 484 | @param maxTests the maximal number of candidate tests |
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| 485 | */ |
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[318] | 486 | Plane3 SelectPlaneHeuristics(PolygonContainer &polys, |
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[325] | 487 | const RayContainer &rays, |
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| 488 | const int maxTests); |
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[238] | 489 | |
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[318] | 490 | /** Extracts the meshes of the objects and adds them to polygons. |
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[260] | 491 | Adds object aabb to the aabb of the tree. |
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[241] | 492 | @param maxPolys the maximal number of objects to be stored as polygons |
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[265] | 493 | @returns the number of polygons |
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[233] | 494 | */ |
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[318] | 495 | int AddToPolygonSoup(const ObjectContainer &objects, |
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| 496 | PolygonContainer &polys, |
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| 497 | int maxObjects = 0); |
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| 498 | |
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| 499 | /** Extracts the meshes of the view cells and and adds them to polygons. |
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[260] | 500 | Adds view cell aabb to the aabb of the tree. |
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| 501 | @param maxPolys the maximal number of objects to be stored as polygons |
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[265] | 502 | @returns the number of polygons |
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[260] | 503 | */ |
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[318] | 504 | int AddToPolygonSoup(const ViewCellContainer &viewCells, |
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| 505 | PolygonContainer &polys, |
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| 506 | int maxObjects = 0); |
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[224] | 507 | |
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[265] | 508 | /** Extract polygons of this mesh and add to polygon container. |
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[286] | 509 | @param mesh the mesh that drives the polygon construction |
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| 510 | @param parent the parent intersectable this polygon is constructed from |
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[265] | 511 | @returns number of polygons |
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[235] | 512 | */ |
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[312] | 513 | int AddMeshToPolygons(Mesh *mesh, PolygonContainer &polys, MeshInstance *parent); |
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[233] | 514 | |
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[305] | 515 | /** returns next candidate index and reorders polygons so no candidate is chosen two times |
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[304] | 516 | @param the current candidate index |
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[295] | 517 | @param max the range of candidates |
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| 518 | */ |
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[305] | 519 | int GetNextCandidateIdx(int currentIdx, PolygonContainer &polys); |
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[295] | 520 | |
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[297] | 521 | /** Helper function which extracts a view cell on the front and the back |
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| 522 | of the split plane. |
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| 523 | @param backViewCell returns view cell on the back of the split plane |
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| 524 | @param frontViewCell returns a view cell on the front of the split plane |
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| 525 | @param coincident container of polygons coincident to the split plane |
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| 526 | @param splitPlane the split plane which decides about back and front |
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| 527 | @param extractBack if a back view cell is extracted |
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[313] | 528 | @param extractFront if a front view cell is extracted |
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[297] | 529 | */ |
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| 530 | void ExtractViewCells(ViewCell **backViewCell, |
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| 531 | ViewCell **frontViewCell, |
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| 532 | const PolygonContainer &coincident, |
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| 533 | const Plane3 splitPlane, |
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[313] | 534 | const bool extractBack, |
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| 535 | const bool extractFront) const; |
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[297] | 536 | |
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[302] | 537 | /** Computes best cost ratio for the suface area heuristics for axis aligned |
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| 538 | splits. This heuristics minimizes the cost for ray traversal. |
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| 539 | @param polys the polygons guiding the ratio computation |
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| 540 | @param box the bounding box of the leaf |
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| 541 | @param axis the current split axis |
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| 542 | @param position returns the split position |
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| 543 | @param objectsBack the number of objects in the back of the split plane |
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| 544 | @param objectsFront the number of objects in the front of the split plane |
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| 545 | */ |
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| 546 | float BestCostRatio(const PolygonContainer &polys, |
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| 547 | const AxisAlignedBox3 &box, |
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| 548 | const int axis, |
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| 549 | float &position, |
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| 550 | int &objectsBack, |
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| 551 | int &objectsFront) const; |
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| 552 | |
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| 553 | /** Sorts split candidates for surface area heuristics for axis aligned splits. |
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| 554 | @param polys the input for choosing split candidates |
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| 555 | @param axis the current split axis |
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| 556 | @param splitCandidates returns sorted list of split candidates |
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| 557 | */ |
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| 558 | void SortSplitCandidates(const PolygonContainer &polys, |
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| 559 | const int axis, |
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| 560 | vector<SortableEntry> &splitCandidates) const; |
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| 561 | |
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[349] | 562 | /** Selects an axis aligned split plane. |
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| 563 | Returns true if split is valied |
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| 564 | */ |
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| 565 | bool SelectAxisAlignedPlane(Plane3 &plane, const PolygonContainer &polys) const; |
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| 566 | |
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[350] | 567 | /** Bounds ray and returns minT and maxT. |
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| 568 | @returns true if ray hits BSP tree bounding box |
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| 569 | */ |
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| 570 | bool BoundRay(const Ray &ray, float &minT, float &maxT) const; |
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| 571 | |
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| 572 | /** Subdivides the rays into front and back rays according to the split plane. |
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| 573 | |
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| 574 | @param plane the split plane |
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| 575 | @param rays contains the rays to be split. The rays are |
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| 576 | distributed into front and back rays. |
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| 577 | @param frontRays returns rays on the front side of the plane |
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| 578 | @param backRays returns rays on the back side of the plane |
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| 579 | |
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| 580 | @returns the number of splits |
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| 581 | */ |
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| 582 | int SplitRays(const Plane3 &plane, |
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| 583 | RayContainer &rays, |
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| 584 | RayContainer &frontRays, |
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| 585 | RayContainer &backRays); |
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| 586 | |
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[233] | 587 | /// Pointer to the root of the tree |
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| 588 | BspNode *mRoot; |
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[237] | 589 | |
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[233] | 590 | /// Pointer to the root cell of the viewspace |
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| 591 | // ViewCell *mRootCell; |
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[237] | 592 | |
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[235] | 593 | BspTreeStatistics mStat; |
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[234] | 594 | |
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[237] | 595 | /// Strategies for choosing next split plane. |
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[297] | 596 | enum {NO_STRATEGY = 0, |
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[321] | 597 | RANDOM_POLYGON = 1, |
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[297] | 598 | AXIS_ALIGNED = 2, |
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| 599 | LEAST_SPLITS = 4, |
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| 600 | BALANCED_POLYS = 8, |
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| 601 | BALANCED_VIEW_CELLS = 16, |
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| 602 | LARGEST_POLY_AREA = 32, |
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[319] | 603 | VERTICAL_AXIS = 64, |
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[332] | 604 | BLOCKED_RAYS = 128, |
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| 605 | LEAST_RAY_SPLITS = 256, |
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| 606 | BALANCED_RAYS = 512 |
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[297] | 607 | }; |
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[236] | 608 | |
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[241] | 609 | /// box around the whole view domain |
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| 610 | AxisAlignedBox3 mBox; |
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| 611 | |
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[297] | 612 | /// view cell corresponding to unbounded space |
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[313] | 613 | ViewCell *mRootCell; |
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[350] | 614 | |
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[344] | 615 | /// should view cells be stored or generated in the leaves? |
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[332] | 616 | bool mGenerateViewCells; |
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| 617 | |
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[350] | 618 | /// if rays should be stored that are piercing this view cell |
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| 619 | bool mStorePiercingRays; |
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| 620 | |
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[235] | 621 | public: |
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| 622 | /// Parses the environment and stores the global BSP tree parameters |
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| 623 | static void ParseEnvironment(); |
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| 624 | |
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[332] | 625 | /// maximal number of polygons before subdivision termination |
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[235] | 626 | static int sTermMaxPolygons; |
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[332] | 627 | /// maximal number of rays before subdivision termination |
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| 628 | static int sTermMaxRays; |
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[235] | 629 | /// maximal possible depth |
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| 630 | static int sTermMaxDepth; |
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[238] | 631 | /// strategy to get the best split plane |
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[236] | 632 | static int sSplitPlaneStrategy; |
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[238] | 633 | /// number of candidates evaluated for the next split plane |
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| 634 | static int sMaxCandidates; |
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[263] | 635 | /// BSP tree construction method |
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| 636 | static int sConstructionMethod; |
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[297] | 637 | /// maximal number of polygons where we do axis aligned splits |
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| 638 | static int sTermMaxPolysForAxisAligned; |
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[263] | 639 | |
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[332] | 640 | /// axis aligned split criteria |
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[303] | 641 | static float sCt_div_ci; |
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[302] | 642 | static float sSplitBorder; |
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| 643 | static float sMaxCostRatio; |
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| 644 | |
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[332] | 645 | // factors guiding the split plane heuristics |
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[296] | 646 | static float sLeastSplitsFactor; |
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[297] | 647 | static float sBalancedPolysFactor; |
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| 648 | static float sBalancedViewCellsFactor; |
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| 649 | static float sVerticalSplitsFactor; |
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[306] | 650 | static float sLargestPolyAreaFactor; |
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[319] | 651 | static float sBlockedRaysFactor; |
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[332] | 652 | static float sLeastRaySplitsFactor; |
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| 653 | static float sBalancedRaysFactor; |
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| 654 | |
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[321] | 655 | /// if polygons should be stored in the tree |
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| 656 | static bool sStoreSplitPolys; |
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[319] | 657 | |
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[263] | 658 | private: |
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| 659 | /** Evaluates split plane classification with respect to the plane's |
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| 660 | contribution for a balanced tree. |
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| 661 | */ |
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[349] | 662 | static float sLeastPolySplitsTable[4]; |
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[263] | 663 | /** Evaluates split plane classification with respect to the plane's |
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| 664 | contribution for a minimum number splits in the tree. |
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| 665 | */ |
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[349] | 666 | static float sBalancedPolysTable[4]; |
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| 667 | /** Evaluates split plane classification with respect to the plane's |
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| 668 | contribution for a minimum number of ray splits. |
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| 669 | */ |
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| 670 | static float sLeastRaySplitsTable[5]; |
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| 671 | /** Evaluates split plane classification with respect to the plane's |
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| 672 | contribution for balanced rays. |
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| 673 | */ |
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| 674 | static float sBalancedRaysTable[5]; |
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| 675 | |
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[233] | 676 | }; |
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| 677 | |
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[221] | 678 | //}; // GtpVisibilityPreprocessor |
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| 679 | |
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| 680 | #endif |
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