1 | #ifndef _ViewCellBsp_H__ |
---|
2 | #define _ViewCellBsp_H__ |
---|
3 | |
---|
4 | #include "Mesh.h" |
---|
5 | #include "Containers.h" |
---|
6 | #include <stack> |
---|
7 | |
---|
8 | class ViewCell; |
---|
9 | class Plane3; |
---|
10 | //class Mesh; |
---|
11 | class BspTree; |
---|
12 | class BspInterior; |
---|
13 | class Polygon3; |
---|
14 | class AxisAlignedBox3; |
---|
15 | class Ray; |
---|
16 | |
---|
17 | //namespace GtpVisibilityPreprocessor { |
---|
18 | |
---|
19 | /** Container storing a soup of polygons used during BSP tree construction |
---|
20 | */ |
---|
21 | typedef vector<Polygon3 *> PolygonContainer; |
---|
22 | typedef vector<Ray *> RayContainer; |
---|
23 | |
---|
24 | struct BspRayTraversalData |
---|
25 | { |
---|
26 | BspNode *mNode; |
---|
27 | Vector3 mExitPoint; |
---|
28 | float mMaxT; |
---|
29 | |
---|
30 | BspRayTraversalData() {} |
---|
31 | |
---|
32 | BspRayTraversalData(BspNode *n, const Vector3 &p, const float maxt): |
---|
33 | mNode(n), mExitPoint(p), mMaxT(maxt) |
---|
34 | {} |
---|
35 | }; |
---|
36 | |
---|
37 | class BspTreeStatistics // TODO: should have common superclass with KdTreeStatistics |
---|
38 | { |
---|
39 | public: |
---|
40 | // total number of nodes |
---|
41 | int nodes; |
---|
42 | // number of splits |
---|
43 | int splits; |
---|
44 | // totals number of rays |
---|
45 | int rays; |
---|
46 | // maximal reached depth |
---|
47 | int maxDepth; |
---|
48 | // minimal depth |
---|
49 | int minDepth; |
---|
50 | // total number of query domains |
---|
51 | int queryDomains; |
---|
52 | // total number of ray references |
---|
53 | int rayRefs; |
---|
54 | // refs in non empty leafs |
---|
55 | int rayRefsNonZeroQuery; |
---|
56 | // total number of query references |
---|
57 | int objectRefs; |
---|
58 | // nodes with zero queries |
---|
59 | int zeroQueryNodes; |
---|
60 | // max depth nodes |
---|
61 | int maxDepthNodes; |
---|
62 | // max number of rays per node |
---|
63 | int maxObjectRefs; |
---|
64 | // number of dynamically added ray refs |
---|
65 | int addedRayRefs; |
---|
66 | // number of dynamically removed ray refs |
---|
67 | int removedRayRefs; |
---|
68 | // accumulated depth (used to compute average) |
---|
69 | int accumDepth; |
---|
70 | // number of initial polygons |
---|
71 | int polys; |
---|
72 | /// number of view cells in leaf |
---|
73 | int viewCellLeaves; |
---|
74 | |
---|
75 | // Constructor |
---|
76 | BspTreeStatistics() |
---|
77 | { |
---|
78 | Reset(); |
---|
79 | } |
---|
80 | |
---|
81 | int Nodes() const {return nodes;} |
---|
82 | int Interior() const { return nodes / 2; } |
---|
83 | int Leaves() const { return (nodes / 2) + 1; } |
---|
84 | double AvgDepth() const { return accumDepth / (double)Leaves();}; // TODO: computation wrong |
---|
85 | |
---|
86 | void Reset() |
---|
87 | { |
---|
88 | nodes = 0; |
---|
89 | splits = 0; |
---|
90 | rays = queryDomains = 0; |
---|
91 | rayRefs = rayRefsNonZeroQuery = objectRefs = 0; |
---|
92 | zeroQueryNodes = 0; |
---|
93 | maxDepthNodes = 0; |
---|
94 | |
---|
95 | maxObjectRefs = 0; |
---|
96 | addedRayRefs = removedRayRefs = 0; |
---|
97 | maxDepth = 0; |
---|
98 | minDepth = 99999; |
---|
99 | polys = 0; |
---|
100 | accumDepth = 0; |
---|
101 | viewCellLeaves = 0; |
---|
102 | } |
---|
103 | |
---|
104 | void |
---|
105 | Print(ostream &app) const; |
---|
106 | |
---|
107 | friend ostream &operator<<(ostream &s, const BspTreeStatistics &stat) { |
---|
108 | stat.Print(s); |
---|
109 | return s; |
---|
110 | } |
---|
111 | |
---|
112 | }; |
---|
113 | |
---|
114 | /** |
---|
115 | BspNode abstract class serving for interior and leaf node implementation |
---|
116 | */ |
---|
117 | class BspNode |
---|
118 | { |
---|
119 | friend BspTree; |
---|
120 | |
---|
121 | public: |
---|
122 | BspNode(); |
---|
123 | virtual ~BspNode(); |
---|
124 | BspNode(BspInterior *parent); |
---|
125 | |
---|
126 | /** Determines whether this node is a leaf or not |
---|
127 | @return true if leaf |
---|
128 | */ |
---|
129 | virtual bool IsLeaf() const = 0; |
---|
130 | |
---|
131 | /** Determines whether this node is a root |
---|
132 | @return true if root |
---|
133 | */ |
---|
134 | virtual bool IsRoot() const; |
---|
135 | |
---|
136 | /** Returns parent node. |
---|
137 | */ |
---|
138 | BspInterior *GetParent(); |
---|
139 | /** Sets parent node. |
---|
140 | */ |
---|
141 | void SetParent(BspInterior *parent); |
---|
142 | |
---|
143 | /** Returns pointer to polygons. |
---|
144 | */ |
---|
145 | PolygonContainer *GetPolygons(); |
---|
146 | /** Stores polygons in node or discards them according to storePolys. |
---|
147 | */ |
---|
148 | void ProcessPolygons(PolygonContainer *polys, const bool storePolys); |
---|
149 | |
---|
150 | //int mViewCellIdx; |
---|
151 | protected: |
---|
152 | |
---|
153 | /// parent of this node |
---|
154 | BspInterior *mParent; |
---|
155 | |
---|
156 | /// store polygons created during BSP splits |
---|
157 | PolygonContainer *mPolygons; |
---|
158 | }; |
---|
159 | |
---|
160 | /** BSP interior node implementation |
---|
161 | */ |
---|
162 | class BspInterior : public BspNode |
---|
163 | { |
---|
164 | public: |
---|
165 | /** Standard contructor taking split plane as argument. |
---|
166 | */ |
---|
167 | BspInterior(const Plane3 &plane); |
---|
168 | /** @return false since it is an interior node |
---|
169 | */ |
---|
170 | bool IsLeaf() const; |
---|
171 | |
---|
172 | BspNode *GetBack(); |
---|
173 | BspNode *GetFront(); |
---|
174 | |
---|
175 | Plane3 *GetPlane(); |
---|
176 | |
---|
177 | void ReplaceChildLink(BspNode *oldChild, BspNode *newChild); |
---|
178 | void SetupChildLinks(BspNode *b, BspNode *f); |
---|
179 | |
---|
180 | /** Splits polygons. |
---|
181 | @param polys the polygons to be split |
---|
182 | @param frontPolys returns the polygons in the front of the split plane |
---|
183 | @param backPolys returns the polygons in the back of the split plane |
---|
184 | @param coincident returns the polygons coincident to the split plane |
---|
185 | @param splits returns the splits number of splits |
---|
186 | @param storePolys if the polygons should be stored in the node |
---|
187 | */ |
---|
188 | void SplitPolygons(PolygonContainer *polys, |
---|
189 | PolygonContainer *frontPolys, |
---|
190 | PolygonContainer *backPolys, |
---|
191 | PolygonContainer *coincident, |
---|
192 | int &splits, |
---|
193 | bool storePolys = false); |
---|
194 | |
---|
195 | /** Stores polygon in node or discards them according to storePolys. |
---|
196 | @param polys the polygons |
---|
197 | @param storePolys if the polygons should be stored or discarded |
---|
198 | */ |
---|
199 | void ProcessPolygon(Polygon3 **poly, const bool storePolys); |
---|
200 | |
---|
201 | friend ostream &operator<<(ostream &s, const BspInterior &A) |
---|
202 | { |
---|
203 | return s << A.mPlane; |
---|
204 | } |
---|
205 | |
---|
206 | protected: |
---|
207 | |
---|
208 | /// Splitting plane corresponding to this node |
---|
209 | Plane3 mPlane; |
---|
210 | /// back node |
---|
211 | BspNode *mBack; |
---|
212 | /// front node |
---|
213 | BspNode *mFront; |
---|
214 | }; |
---|
215 | |
---|
216 | /** BSP leaf node implementation. |
---|
217 | */ |
---|
218 | class BspLeaf : public BspNode |
---|
219 | { |
---|
220 | friend BspTree; |
---|
221 | |
---|
222 | public: |
---|
223 | BspLeaf(); |
---|
224 | BspLeaf(ViewCell *viewCell); |
---|
225 | BspLeaf(BspInterior *parent); |
---|
226 | BspLeaf(BspInterior *parent, ViewCell *viewCell); |
---|
227 | |
---|
228 | /** @return true since it is an interior node |
---|
229 | */ |
---|
230 | bool IsLeaf() const; |
---|
231 | /** Returns pointer from view cell. |
---|
232 | */ |
---|
233 | ViewCell *GetViewCell(); |
---|
234 | /** Sets pointer to view cell. |
---|
235 | */ |
---|
236 | void SetViewCell(ViewCell *viewCell); |
---|
237 | |
---|
238 | protected: |
---|
239 | |
---|
240 | /// polygonal representation of this viewcell |
---|
241 | /// if NULL this note does not correspond to feasible viewcell |
---|
242 | ViewCell *mViewCell; |
---|
243 | }; |
---|
244 | |
---|
245 | |
---|
246 | /** Implementation of the ViewCell BSP tree. */ |
---|
247 | class BspTree |
---|
248 | { |
---|
249 | public: |
---|
250 | |
---|
251 | /** Additional data which is passed down the BSP tree during traversal. |
---|
252 | */ |
---|
253 | struct BspTraversalData |
---|
254 | { |
---|
255 | /// the current node |
---|
256 | BspNode *mNode; |
---|
257 | /// polygonal data for splitting |
---|
258 | PolygonContainer *mPolygons; |
---|
259 | /// current depth |
---|
260 | int mDepth; |
---|
261 | /// the view cell associated with this subdivsion |
---|
262 | ViewCell *mViewCell; |
---|
263 | /// if the node is an inside or outside node with respect to the parent plane |
---|
264 | //bool mIsInside; |
---|
265 | BspTraversalData() {} |
---|
266 | |
---|
267 | BspTraversalData(BspNode *node, PolygonContainer *polys, const int depth, ViewCell *viewCell): |
---|
268 | mNode(node), mPolygons(polys), mDepth(depth), mViewCell(viewCell) {} |
---|
269 | }; |
---|
270 | |
---|
271 | typedef std::stack<BspTraversalData> BspTraversalStack; |
---|
272 | |
---|
273 | /// BSP tree construction type |
---|
274 | enum {VIEW_CELLS, SCENE_GEOMETRY, RAYS}; |
---|
275 | |
---|
276 | /** Default constructor creating an empty tree. |
---|
277 | */ |
---|
278 | BspTree(); |
---|
279 | |
---|
280 | ~BspTree(); |
---|
281 | |
---|
282 | const BspTreeStatistics &GetStatistics() const; |
---|
283 | |
---|
284 | /** Constructs tree using the given list of view cells.
|
---|
285 | For this type of construction we filter all view cells down the |
---|
286 | tree. If there is no polygon left, the last split plane |
---|
287 | decides inside or outside of the viewcell. A pointer to the
|
---|
288 | appropriate view cell is stored within each leaf.
|
---|
289 | Many leafs can point to the same viewcell.
|
---|
290 | */
|
---|
291 | void Construct(const ViewCellContainer &viewCells);
|
---|
292 |
|
---|
293 | /** Constructs tree using the given list of objects.
|
---|
294 | Note that the objects are not taken as view cells, but the view cells are
|
---|
295 | constructed from the subdivision: Each leaf is taken as one viewcell;
|
---|
296 |
|
---|
297 | @param objects list of objects
|
---|
298 | @returns list of view cells.
|
---|
299 | */
|
---|
300 | void Construct(const ObjectContainer &objects, ViewCellContainer *viewCells); |
---|
301 | |
---|
302 | /** Constructs tree using the given number of rays
|
---|
303 | @param objects list of objects
|
---|
304 | @returns list of view cells.
|
---|
305 | */ |
---|
306 | void Construct(const RayContainer &rays, ViewCellContainer *viewCells); |
---|
307 | |
---|
308 | int CollectLeafPvs(); |
---|
309 | |
---|
310 | void CollectLeaves(vector<BspLeaf *> &leaves); |
---|
311 | |
---|
312 | /** Returns box which bounds the whole tree. |
---|
313 | */ |
---|
314 | AxisAlignedBox3 GetBoundingBox()const; |
---|
315 | |
---|
316 | /** Returns root of BSP tree. |
---|
317 | */ |
---|
318 | BspNode *GetRoot() const; |
---|
319 | |
---|
320 | /** If the view cell polygons are stored in the nodes. |
---|
321 | */ |
---|
322 | bool StorePolys() const; |
---|
323 | |
---|
324 | /** Exports Bsp tree to file. |
---|
325 | */ |
---|
326 | bool Export(const string filename); |
---|
327 | |
---|
328 | //static bool displayDebug; |
---|
329 | protected: |
---|
330 | |
---|
331 | /** Initialises BSP tree. |
---|
332 | @param maxPolygons the maximal polygon count before termination of |
---|
333 | subdivision |
---|
334 | @param maxDepth the maximal depth before termination of |
---|
335 | subdivision |
---|
336 | */ |
---|
337 | void InitTree(int maxPolygons, int maxDepth); |
---|
338 | |
---|
339 | /** Constructs the tree from the given list of polygons. |
---|
340 | @param viewCells if not NULL, new view cells are |
---|
341 | created in the leafs and stored in the conatainer |
---|
342 | */ |
---|
343 | void Construct(PolygonContainer *polys, ViewCellContainer *viewCells = NULL); |
---|
344 | |
---|
345 | /** Evaluates the contribution of the candidate split plane. |
---|
346 | */ |
---|
347 | int EvalSplitPlane(PolygonContainer *polygons, const Plane3 &candidatePlane) const; |
---|
348 | |
---|
349 | /** Evaluates tree stats in the BSP tree leafs. |
---|
350 | */ |
---|
351 | void EvaluateLeafStats(const BspTraversalData &data); |
---|
352 | |
---|
353 | /** Subdivides node with respect to the traversal data. |
---|
354 | @param tStack current traversal stack |
---|
355 | @param tData traversal data also holding node to be subdivided |
---|
356 | @param viewCellContainer if not null, a new viewcell is created and stored in the container |
---|
357 | @returns new root of the subtree |
---|
358 | */ |
---|
359 | BspNode *Subdivide(BspTraversalStack &tStack, BspTraversalData &tData, ViewCellContainer *viewCells = NULL); |
---|
360 | |
---|
361 | /** Selects a splitting plane. |
---|
362 | @param polys the polygon list on which the split decition is based |
---|
363 | */ |
---|
364 | Plane3 SelectPlane(PolygonContainer *polys) const; |
---|
365 |
|
---|
366 | /** Filters next view cell down the tree and inserts it into the appropriate leaves
|
---|
367 | (i.e., possibly more than one leaf).
|
---|
368 | */
|
---|
369 | void InsertViewCell(ViewCell *viewCell); |
---|
370 | /** Inserts polygons down the tree. The polygons are filtered until a leaf is reached,
|
---|
371 | then further subdivided.
|
---|
372 | @param viewCellContainer if not null, a new viewcell is created and stored in the container
|
---|
373 | */
|
---|
374 | void InsertPolygons(PolygonContainer *polys, ViewCellContainer *viewCells = NULL);
|
---|
375 |
|
---|
376 | /** Subdivide leaf.
|
---|
377 | @param leaf the leaf to be subdivided
|
---|
378 | @param polys the input polygons
|
---|
379 | @param frontPolys returns the polygons in the front of the split plane
|
---|
380 | @param backPolys returns the polygons in the back of the split plane
|
---|
381 | @param coincident returns the polygons coincident to the split plane
|
---|
382 | @returns the root of the subdivision
|
---|
383 | */
|
---|
384 | BspInterior *SubdivideNode(BspLeaf *leaf,
|
---|
385 | PolygonContainer *polys, |
---|
386 | PolygonContainer *frontPolys, |
---|
387 | PolygonContainer *backPolys, |
---|
388 | PolygonContainer *coincident); |
---|
389 | |
---|
390 | /** Filters polygons down the tree. |
---|
391 | @param node the current BSP node |
---|
392 | @param polys the polygons to be filtered |
---|
393 | @param frontPolys returns the polygons in front of the split plane |
---|
394 | @param backPolys returns the polygons in the back of the split plane |
---|
395 | */ |
---|
396 | void FilterPolygons(BspInterior *node, PolygonContainer *polys, |
---|
397 | PolygonContainer *frontPolys, PolygonContainer *backPolys); |
---|
398 | |
---|
399 | /** Selects the split plane in order to get a balanced tree. |
---|
400 | @param polygons container of polygons |
---|
401 | @param maxTests the maximal number of candidate tests |
---|
402 | */ |
---|
403 | Plane3 SelectPlaneHeuristics(PolygonContainer *polygons, int maxTests) const; |
---|
404 | |
---|
405 | /** Extracts the meshes of the objects and copies them into the mesh. |
---|
406 | Adds object aabb to the aabb of the tree. |
---|
407 | @param maxPolys the maximal number of objects to be stored as polygons |
---|
408 | @returns the number of polygons |
---|
409 | */ |
---|
410 | int Copy2PolygonSoup(const ObjectContainer &objects, PolygonContainer &polys, int maxObjects = 0); |
---|
411 | /** Extracts the meshes of the view cells and copies them into the mesh. |
---|
412 | Adds view cell aabb to the aabb of the tree. |
---|
413 | @param maxPolys the maximal number of objects to be stored as polygons |
---|
414 | @returns the number of polygons |
---|
415 | */ |
---|
416 | int Copy2PolygonSoup(const ViewCellContainer &viewCells, PolygonContainer &polys, int maxObjects = 0); |
---|
417 | |
---|
418 | /** Extract polygons of this mesh and add to polygon container. |
---|
419 | @param mesh the mesh that drives the polygon construction |
---|
420 | @param parent the parent intersectable this polygon is constructed from |
---|
421 | @returns number of polygons |
---|
422 | */ |
---|
423 | int AddMesh2Polygons(Mesh *mesh, PolygonContainer &polys, Intersectable *parent = NULL); |
---|
424 | |
---|
425 | /** A ray is cast possible intersecting the tree. |
---|
426 | @param the ray that is cast. |
---|
427 | @returns the number of intersections with objects stored in the tree. |
---|
428 | */ |
---|
429 | int CastRay(Ray &ray); |
---|
430 | |
---|
431 | /// Pointer to the root of the tree |
---|
432 | BspNode *mRoot; |
---|
433 | |
---|
434 | /// Pointer to the root cell of the viewspace |
---|
435 | // ViewCell *mRootCell; |
---|
436 | |
---|
437 | BspTreeStatistics mStat; |
---|
438 | |
---|
439 | /// local maximal polygons (changes depending on method) |
---|
440 | int mTermMaxPolygons; |
---|
441 | int mTermMaxDepth; |
---|
442 | |
---|
443 | /// Strategies for choosing next split plane. |
---|
444 | enum {NEXT_POLYGON, LEAST_SPLITS, BALANCED_TREE, COMBINED}; |
---|
445 | |
---|
446 | /// box around the whole view domain |
---|
447 | AxisAlignedBox3 mBox; |
---|
448 | |
---|
449 | /// if view cell calculation is incremential |
---|
450 | bool mIsIncremential; |
---|
451 | |
---|
452 | /// if polygons should be stored in the tree |
---|
453 | bool mStorePolys; |
---|
454 | |
---|
455 | public: |
---|
456 | /// Parses the environment and stores the global BSP tree parameters |
---|
457 | static void ParseEnvironment(); |
---|
458 | |
---|
459 | /// maximal number of polygons where tree construction is terminated |
---|
460 | static int sTermMaxPolygons; |
---|
461 | /// maximal possible depth |
---|
462 | static int sTermMaxDepth; |
---|
463 | /// strategy to get the best split plane |
---|
464 | static int sSplitPlaneStrategy; |
---|
465 | /// number of candidates evaluated for the next split plane |
---|
466 | static int sMaxCandidates; |
---|
467 | /// BSP tree construction method |
---|
468 | static int sConstructionMethod; |
---|
469 | |
---|
470 | private: |
---|
471 | /** Evaluates split plane classification with respect to the plane's |
---|
472 | contribution for a balanced tree. |
---|
473 | */ |
---|
474 | static int sLeastSplitsTable[4]; |
---|
475 | /** Evaluates split plane classification with respect to the plane's |
---|
476 | contribution for a minimum number splits in the tree. |
---|
477 | */ |
---|
478 | static int sBalancedTreeTable[4]; |
---|
479 | }; |
---|
480 | |
---|
481 | //}; // GtpVisibilityPreprocessor |
---|
482 | |
---|
483 | #endif |
---|