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source: GTP/trunk/Lib/Vis/Preprocessing/src/ViewCellBsp.cpp @ 1418

Revision 1418, 81.3 KB checked in by mattausch, 18 years ago (diff)

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1	#include "Plane3.h"
2	#include "ViewCellBsp.h"
3	#include "Mesh.h"
4	#include "common.h"
5	#include "ViewCell.h"
6	#include "Environment.h"
7	#include "Polygon3.h"
8	#include "Ray.h"
9	#include "AxisAlignedBox3.h"
10	#include "Triangle3.h"
11	#include "Tetrahedron3.h"
12	#include "ViewCellsManager.h"
13	#include "Exporter.h"
14	#include "Plane3.h"
15	#include <stack>
16
17	namespace GtpVisibilityPreprocessor {
18
19
20	//-- static members
21
22	int BspNode::sMailId = 1;
23
24	/** Evaluates split plane classification with respect to the plane's
25	contribution for a minimum number splits in the tree.
26	*/
27	const float BspTree::sLeastPolySplitsTable[] = {0, 0, 1, 0};
28	/** Evaluates split plane classification with respect to the plane's
29	contribution for a balanced tree.
30	*/
31	const float BspTree::sBalancedPolysTable[] = {1, -1, 0, 0};
32
33	/** Evaluates split plane classification with respect to the plane's
34	contribution for a minimum number of ray splits.
35	*/
36	const float BspTree::sLeastRaySplitsTable[] = {0, 0, 1, 1, 0};
37	/** Evaluates split plane classification with respect to the plane's
38	contribution for balanced rays.
39	*/
40	const float BspTree::sBalancedRaysTable[] = {1, -1, 0, 0, 0};
41
42	int BspTree::sFrontId = 0;
43	int BspTree::sBackId = 0;
44	int BspTree::sFrontAndBackId = 0;
45
46
47	/******************************************************************/
48	/* class BspNode implementation */
49	/******************************************************************/
50
51
52	BspNode::BspNode():
53	mParent(NULL), mTreeValid(true), mTimeStamp(0)
54	{}
55
56
57	BspNode::BspNode(BspInterior *parent):
58	mParent(parent), mTreeValid(true)
59	{}
60
61
62	bool BspNode::IsSibling(BspNode *n) const
63	{
64	return ((this != n) && mParent &&
65	(mParent->GetFront() == n) \|\| (mParent->GetBack() == n));
66	}
67
68
69	int BspNode::GetDepth() const
70	{
71	int depth = 0;
72	BspNode *p = mParent;
73
74	while (p)
75	{
76	p = p->mParent;
77	++ depth;
78	}
79
80	return depth;
81	}
82
83
84	bool BspNode::TreeValid() const
85	{
86	return mTreeValid;
87	}
88
89
90	void BspNode::SetTreeValid(const bool v)
91	{
92	mTreeValid = v;
93	}
94
95
96	/****************************************************************/
97	/* class BspInterior implementation */
98	/****************************************************************/
99
100
101	BspInterior::BspInterior(const Plane3 &plane):
102	mPlane(plane), mFront(NULL), mBack(NULL)
103	{}
104
105	BspInterior::~BspInterior()
106	{
107	DEL_PTR(mFront);
108	DEL_PTR(mBack);
109	}
110
111
112	void BspInterior::SetupChildLinks(BspNode b, BspNode f)
113	{
114	mBack = b;
115	mFront = f;
116	}
117
118
119	/****************************************************************/
120	/* class BspLeaf implementation */
121	/****************************************************************/
122
123
124	BspLeaf::BspLeaf(): mViewCell(NULL), mPvs(NULL)
125	{
126	}
127
128
129	BspLeaf::~BspLeaf()
130	{
131	DEL_PTR(mPvs);
132
133	VssRayContainer::const_iterator vit, vit_end = mVssRays.end();
134	for (vit = mVssRays.begin(); vit != vit_end; ++ vit)
135	{
136	VssRay ray = vit;
137	ray->Unref();
138
139	if (!ray->IsActive())
140	delete ray;
141	}
142	}
143
144
145	BspLeaf::BspLeaf(ViewCellLeaf *viewCell):
146	mViewCell(viewCell)
147	{
148	}
149
150
151	BspLeaf::BspLeaf(BspInterior *parent):
152	BspNode(parent), mViewCell(NULL), mPvs(NULL)
153	{}
154
155
156
157	BspLeaf::BspLeaf(BspInterior parent, ViewCellLeaf viewCell):
158	BspNode(parent), mViewCell(viewCell), mPvs(NULL)
159	{
160	}
161
162
163	/*********************************************************************/
164	/* class BspTree implementation */
165	/*********************************************************************/
166
167	BspTree::BspTree():
168	mRoot(NULL),
169	mUseAreaForPvs(false),
170	mGenerateViewCells(true),
171	mTimeStamp(1)
172	{
173	Randomize(); // initialise random generator for heuristics
174
175	mOutOfBoundsCell = GetOrCreateOutOfBoundsCell();
176
177	//-- termination criteria for autopartition
178	Environment::GetSingleton()->GetIntValue("BspTree.Termination.maxDepth", mTermMaxDepth);
179	Environment::GetSingleton()->GetIntValue("BspTree.Termination.minPvs", mTermMinPvs);
180	Environment::GetSingleton()->GetIntValue("BspTree.Termination.minPolygons", mTermMinPolys);
181	Environment::GetSingleton()->GetIntValue("BspTree.Termination.minRays", mTermMinRays);
182	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.minProbability", mTermMinProbability);
183	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.maxRayContribution", mTermMaxRayContribution);
184	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.minAccRayLenght", mTermMinAccRayLength);
185
186	//-- factors for bsp tree split plane heuristics
187	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.verticalSplits", mVerticalSplitsFactor);
188	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.largestPolyArea", mLargestPolyAreaFactor);
189	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.blockedRays", mBlockedRaysFactor);
190	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.leastRaySplits", mLeastRaySplitsFactor);
191	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.balancedRays", mBalancedRaysFactor);
192	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.pvs", mPvsFactor);
193	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.leastSplits" , mLeastSplitsFactor);
194	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.balancedPolys", mBalancedPolysFactor);
195	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.balancedViewCells", mBalancedViewCellsFactor);
196	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.ct_div_ci", mCtDivCi);
197
198	//-- termination criteria for axis aligned split
199	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.AxisAligned.ct_div_ci", mAxisAlignedCtDivCi);
200	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.maxCostRatio", mMaxCostRatio);
201	Environment::GetSingleton()->GetIntValue("BspTree.Termination.AxisAligned.minPolys",
202	mTermMinPolysForAxisAligned);
203	Environment::GetSingleton()->GetIntValue("BspTree.Termination.AxisAligned.minRays",
204	mTermMinRaysForAxisAligned);
205	Environment::GetSingleton()->GetIntValue("BspTree.Termination.AxisAligned.minObjects",
206	mTermMinObjectsForAxisAligned);
207	//-- partition criteria
208	Environment::GetSingleton()->GetIntValue("BspTree.maxPolyCandidates", mMaxPolyCandidates);
209	Environment::GetSingleton()->GetIntValue("BspTree.maxRayCandidates", mMaxRayCandidates);
210	Environment::GetSingleton()->GetIntValue("BspTree.splitPlaneStrategy", mSplitPlaneStrategy);
211	Environment::GetSingleton()->GetFloatValue("BspTree.AxisAligned.splitBorder", mSplitBorder);
212	Environment::GetSingleton()->GetIntValue("BspTree.maxTests", mMaxTests);
213	Environment::GetSingleton()->GetIntValue("BspTree.Termination.maxViewCells", mMaxViewCells);
214
215	Environment::GetSingleton()->GetFloatValue("BspTree.Construction.epsilon", mEpsilon);
216
217	char subdivisionStatsLog[100];
218	Environment::GetSingleton()->GetStringValue("BspTree.subdivisionStats", subdivisionStatsLog);
219	mSubdivisionStats.open(subdivisionStatsLog);
220
221	Debug << "BSP max depth: " << mTermMaxDepth << endl;
222	Debug << "BSP min PVS: " << mTermMinPvs << endl;
223	Debug << "BSP min probability: " << mTermMinProbability << endl;
224	Debug << "BSP max polys: " << mTermMinPolys << endl;
225	Debug << "BSP max rays: " << mTermMinRays << endl;
226	Debug << "BSP max polygon candidates: " << mMaxPolyCandidates << endl;
227	Debug << "BSP max plane candidates: " << mMaxRayCandidates << endl;
228
229	Debug << "Split plane strategy: ";
230	if (mSplitPlaneStrategy & RANDOM_POLYGON)
231	Debug << "random polygon ";
232	if (mSplitPlaneStrategy & AXIS_ALIGNED)
233	Debug << "axis aligned ";
234	if (mSplitPlaneStrategy & LEAST_SPLITS)
235	Debug << "least splits ";
236	if (mSplitPlaneStrategy & BALANCED_POLYS)
237	Debug << "balanced polygons ";
238	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
239	Debug << "balanced view cells ";
240	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
241	Debug << "largest polygon area ";
242	if (mSplitPlaneStrategy & VERTICAL_AXIS)
243	Debug << "vertical axis ";
244	if (mSplitPlaneStrategy & BLOCKED_RAYS)
245	Debug << "blocked rays ";
246	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
247	Debug << "least ray splits ";
248	if (mSplitPlaneStrategy & BALANCED_RAYS)
249	Debug << "balanced rays ";
250	if (mSplitPlaneStrategy & PVS)
251	Debug << "pvs";
252
253	Debug << endl;
254	}
255
256
257	const BspTreeStatistics &BspTree::GetStatistics() const
258	{
259	return mStat;
260	}
261
262
263	int BspTree::SplitPolygons(const Plane3 &plane,
264	PolygonContainer &polys,
265	PolygonContainer &frontPolys,
266	PolygonContainer &backPolys,
267	PolygonContainer &coincident) const
268	{
269	int splits = 0;
270
271	#ifdef _Debug
272	Debug << "splitting polygons of node " << this << " with plane " << mPlane << endl;
273	#endif
274
275	PolygonContainer::const_iterator it, it_end = polys.end();
276
277	for (it = polys.begin(); it != polys.end(); ++ it)
278	{
279	Polygon3 poly = it;
280
281	//-- classify polygon
282	const int cf = poly->ClassifyPlane(plane, mEpsilon);
283
284	switch (cf)
285	{
286	case Polygon3::COINCIDENT:
287	coincident.push_back(poly);
288	break;
289	case Polygon3::FRONT_SIDE:
290	frontPolys.push_back(poly);
291	break;
292	case Polygon3::BACK_SIDE:
293	backPolys.push_back(poly);
294	break;
295	case Polygon3::SPLIT:
296	{
297	Polygon3 *front_piece = new Polygon3(poly->mParent);
298	Polygon3 *back_piece = new Polygon3(poly->mParent);
299
300	//-- split polygon into front and back part
301	poly->Split(plane,
302	*front_piece,
303	*back_piece,
304	mEpsilon);
305
306	++ splits; // increase number of splits
307
308	//-- inherit rays from parent polygon for blocked ray criterium
309	poly->InheritRays(front_piece, back_piece);
310
311	// check if polygons still valid
312	if (front_piece->Valid(mEpsilon))
313	frontPolys.push_back(front_piece);
314	else
315	DEL_PTR(front_piece);
316
317	if (back_piece->Valid(mEpsilon))
318	backPolys.push_back(back_piece);
319	else
320	DEL_PTR(back_piece);
321
322	#ifdef _DEBUG
323	Debug << "split " << poly << endl << front_piece << endl << *back_piece << endl;
324	#endif
325	DEL_PTR(poly);
326	}
327	break;
328	default:
329	Debug << "SHOULD NEVER COME HERE\n";
330	break;
331	}
332	}
333
334	return splits;
335	}
336
337
338	void BspTreeStatistics::Print(ostream &app) const
339	{
340	app << "===== BspTree statistics ===============\n";
341
342	app << setprecision(4);
343
344	app << "#N_CTIME ( Construction time [s] )\n" << Time() << " \n";
345
346	app << "#N_NODES ( Number of nodes )\n" << nodes << "\n";
347
348	app << "#N_INTERIORS ( Number of interior nodes )\n" << Interior() << "\n";
349
350	app << "#N_LEAVES ( Number of leaves )\n" << Leaves() << "\n";
351
352	app << "#N_POLYSPLITS ( Number of polygon splits )\n" << polySplits << "\n";
353
354	app << "#AXIS_ALIGNED_SPLITS (number of axis aligned splits)\n" << splits[0] + splits[1] + splits[2] << endl;
355
356	app << "#N_SPLITS ( Number of splits in axes x y z)\n";
357
358	for (int i = 0; i < 3; ++ i)
359	app << splits[i] << " ";
360	app << endl;
361
362	app << "#N_PMAXDEPTHLEAVES ( Percentage of leaves at maximum depth )\n"
363	<< maxDepthNodes * 100 / (double)Leaves() << endl;
364
365	app << "#N_PMINPVSLEAVES ( Percentage of leaves with mininimal PVS )\n"
366	<< minPvsNodes * 100 / (double)Leaves() << endl;
367
368	app << "#N_PMINRAYSLEAVES ( Percentage of leaves with minimal number of rays)\n"
369	<< minRaysNodes * 100 / (double)Leaves() << endl;
370
371	app << "#N_MAXCOSTNODES ( Percentage of leaves with terminated because of max cost ratio )\n"
372	<< maxCostNodes * 100 / (double)Leaves() << endl;
373
374	app << "#N_PMINPROBABILITYLEAVES ( Percentage of leaves with mininum probability )\n"
375	<< minProbabilityNodes * 100 / (double)Leaves() << endl;
376
377	app << "#N_PMAXRAYCONTRIBLEAVES ( Percentage of leaves with maximal ray contribution )\n"
378	<< maxRayContribNodes * 100 / (double)Leaves() << endl;
379
380	app << "#N_PMAXDEPTH ( Maximal reached depth )\n" << maxDepth << endl;
381
382	app << "#N_PMINDEPTH ( Minimal reached depth )\n" << minDepth << endl;
383
384	app << "#AVGDEPTH ( average depth )\n" << AvgDepth() << endl;
385
386	app << "#N_INPUTPOLYGONS (number of input polygons )\n" << polys << endl;
387
388	app << "#N_INVALIDLEAVES (number of invalid leaves )\n" << invalidLeaves << endl;
389
390	app << "#N_RAYS (number of rays / leaf)\n" << AvgRays() << endl;
391	//app << "#N_PVS: " << pvs << endl;
392
393	app << "#N_ROUTPUT_INPUT_POLYGONS ( ratio polygons after subdivision / input polygons )\n" <<
394	(polys + polySplits) / (double)polys << endl;
395
396	app << "===== END OF BspTree statistics ==========\n";
397	}
398
399
400	BspTree::~BspTree()
401	{
402	DEL_PTR(mRoot);
403
404	// TODO must be deleted if used!!
405	//if (mGenerateViewCells) DEL_PTR(mOutOfBoundsCell);
406	}
407
408	BspViewCell *BspTree::GetOutOfBoundsCell()
409	{
410	return mOutOfBoundsCell;
411	}
412
413
414	BspNode *BspTree::GetRoot() const
415	{
416	return mRoot;
417	}
418
419
420	BspViewCell *BspTree::GetOrCreateOutOfBoundsCell()
421	{
422	if (!mOutOfBoundsCell)
423	{
424	mOutOfBoundsCell = new BspViewCell();
425	mOutOfBoundsCell->SetId(-1);
426	mOutOfBoundsCell->SetValid(false);
427	}
428
429	return mOutOfBoundsCell;
430	}
431
432
433	void BspTree::InsertViewCell(ViewCellLeaf *viewCell)
434	{
435	PolygonContainer *polys = new PolygonContainer();
436
437	// don't generate new view cell, insert this one
438	mGenerateViewCells = false;
439	// extract polygons that guide the split process
440	mStat.polys += AddMeshToPolygons(viewCell->GetMesh(), *polys, viewCell);
441	mBox.Include(viewCell->GetBox()); // add to BSP aabb
442
443	InsertPolygons(polys);
444	}
445
446
447	void BspTree::InsertPolygons(PolygonContainer *polys)
448	{
449	BspTraversalStack tStack;
450
451	// traverse existing tree or create new tree
452	if (!mRoot)
453	mRoot = new BspLeaf();
454
455	tStack.push(BspTraversalData(mRoot,
456	polys,
457	0,
458	mOutOfBoundsCell,
459	new BoundedRayContainer(),
460	0,
461	mUseAreaForPvs ? mBox.SurfaceArea() : mBox.GetVolume(),
462	new BspNodeGeometry()));
463
464	while (!tStack.empty())
465	{
466	// filter polygons donw the tree
467	BspTraversalData tData = tStack.top();
468	tStack.pop();
469
470	if (!tData.mNode->IsLeaf())
471	{
472	BspInterior interior = dynamic_cast<BspInterior >(tData.mNode);
473
474	//-- filter view cell polygons down the tree until a leaf is reached
475	if (!tData.mPolygons->empty())
476	{
477	PolygonContainer *frontPolys = new PolygonContainer();
478	PolygonContainer *backPolys = new PolygonContainer();
479	PolygonContainer coincident;
480
481	int splits = 0;
482
483	// split viewcell polygons with respect to split plane
484	splits += SplitPolygons(interior->GetPlane(),
485	*tData.mPolygons,
486	*frontPolys,
487	*backPolys,
488	coincident);
489
490	// extract view cells associated with the split polygons
491	ViewCellLeaf *frontViewCell = GetOrCreateOutOfBoundsCell();
492	ViewCellLeaf *backViewCell = GetOrCreateOutOfBoundsCell();
493
494	BspTraversalData frontData(interior->GetFront(),
495	frontPolys,
496	tData.mDepth + 1,
497	mOutOfBoundsCell,
498	tData.mRays,
499	tData.mPvs,
500	mUseAreaForPvs ? mBox.SurfaceArea() : mBox.GetVolume(),
501	new BspNodeGeometry());
502
503	BspTraversalData backData(interior->GetBack(),
504	backPolys,
505	tData.mDepth + 1,
506	mOutOfBoundsCell,
507	tData.mRays,
508	tData.mPvs,
509	mUseAreaForPvs ? mBox.SurfaceArea() : mBox.GetVolume(),
510	new BspNodeGeometry());
511
512	if (!mGenerateViewCells)
513	{
514	ExtractViewCells(frontData,
515	backData,
516	coincident,
517	interior->mPlane);
518	}
519
520	// don't need coincident polygons anymore
521	CLEAR_CONTAINER(coincident);
522
523	mStat.polySplits += splits;
524
525	// push the children on the stack
526	tStack.push(frontData);
527	tStack.push(backData);
528	}
529
530	// cleanup
531	DEL_PTR(tData.mPolygons);
532	DEL_PTR(tData.mRays);
533	}
534	else
535	{
536	// reached leaf => subdivide current viewcell
537	BspNode *subRoot = Subdivide(tStack, tData);
538	}
539	}
540	}
541
542
543	int BspTree::AddMeshToPolygons(Mesh *mesh,
544	PolygonContainer &polys,
545	MeshInstance *parent)
546	{
547	FaceContainer::const_iterator fi, fi_end = mesh->mFaces.end();
548
549	// copy the face data to polygons
550	for (fi = mesh->mFaces.begin(); fi != fi_end; ++ fi)
551	{
552	Polygon3 poly = new Polygon3((fi), mesh);
553
554	if (poly->Valid(mEpsilon))
555	{
556	poly->mParent = parent; // set parent intersectable
557	polys.push_back(poly);
558	}
559	else
560	DEL_PTR(poly);
561	}
562	return (int)mesh->mFaces.size();
563	}
564
565
566	int BspTree::AddToPolygonSoup(const ViewCellContainer &viewCells,
567	PolygonContainer &polys,
568	int maxObjects)
569	{
570	int limit = (maxObjects > 0) ?
571	Min((int)viewCells.size(), maxObjects) : (int)viewCells.size();
572
573	int polysSize = 0;
574
575	for (int i = 0; i < limit; ++ i)
576	{
577	if (viewCells[i]->GetMesh()) // copy the mesh data to polygons
578	{
579	mBox.Include(viewCells[i]->GetBox()); // add to BSP tree aabb
580	polysSize += AddMeshToPolygons(viewCells[i]->GetMesh(), polys, viewCells[i]);
581	}
582	}
583
584	return polysSize;
585	}
586
587
588	int BspTree::AddToPolygonSoup(const ObjectContainer &objects,
589	PolygonContainer &polys,
590	int maxObjects,
591	bool addToBbox)
592	{
593	int limit = (maxObjects > 0) ?
594	Min((int)objects.size(), maxObjects) : (int)objects.size();
595
596	for (int i = 0; i < limit; ++i)
597	{
598	Intersectable *object = objects[i];
599
600	Mesh *mesh = NULL;
601
602	switch (object->Type()) // extract the meshes
603	{
604	case Intersectable::MESH_INSTANCE:
605	mesh = dynamic_cast<MeshInstance *>(object)->GetMesh();
606	break;
607	case Intersectable::VIEW_CELL:
608	mesh = dynamic_cast<ViewCell *>(object)->GetMesh();
609	break;
610	case Intersectable::TRANSFORMED_MESH_INSTANCE:
611	{
612	TransformedMeshInstance mi = dynamic_cast<TransformedMeshInstance >(object);
613
614	if (!mi->GetMesh())
615	break;
616	mesh = new Mesh();
617	mi->GetTransformedMesh(*mesh);
618
619	break;
620	}
621	default:
622	Debug << "intersectable type not supported" << endl;
623	break;
624	}
625
626	if (mesh) // copy the mesh data to polygons
627	{
628	if (addToBbox)
629	mBox.Include(object->GetBox()); // add to BSP tree aabb
630
631	AddMeshToPolygons(mesh, polys, mOutOfBoundsCell);
632
633	// cleanup
634	if (object->Type() == Intersectable::TRANSFORMED_MESH_INSTANCE)
635	DEL_PTR(mesh);
636	}
637	}
638
639	return (int)polys.size();
640	}
641
642
643	void BspTree::Construct(const ViewCellContainer &viewCells)
644	{
645	mStat.nodes = 1;
646	mBox.Initialize(); // initialise bsp tree bounding box
647
648	// copy view cell meshes into one big polygon soup
649	PolygonContainer *polys = new PolygonContainer();
650	mStat.polys = AddToPolygonSoup(viewCells, *polys);
651
652	// view cells are given
653	mGenerateViewCells = false;
654	// construct tree from the view cell polygons
655	Construct(polys, new BoundedRayContainer());
656	}
657
658
659	void BspTree::Construct(const ObjectContainer &objects)
660	{
661	mStat.nodes = 1;
662	mBox.Initialize(); // initialise bsp tree bounding box
663
664	PolygonContainer *polys = new PolygonContainer();
665
666	mGenerateViewCells = true;
667	// copy mesh instance polygons into one big polygon soup
668	mStat.polys = AddToPolygonSoup(objects, *polys);
669
670	// construct tree from polygon soup
671	Construct(polys, new BoundedRayContainer());
672	}
673
674
675	void BspTree::PreprocessPolygons(PolygonContainer &polys)
676	{
677	// preprocess: throw out polygons coincident to the view space box (not needed)
678	PolygonContainer boxPolys;
679	mBox.ExtractPolys(boxPolys);
680	vector<Plane3> boxPlanes;
681
682	PolygonContainer::iterator pit, pit_end = boxPolys.end();
683
684	// extract planes of box
685	// TODO: can be done more elegantly than first extracting polygons
686	// and take their planes
687	for (pit = boxPolys.begin(); pit != pit_end; ++ pit)
688	{
689	boxPlanes.push_back((*pit)->GetSupportingPlane());
690	}
691
692	pit_end = polys.end();
693
694	for (pit = polys.begin(); pit != pit_end; ++ pit)
695	{
696	vector<Plane3>::const_iterator bit, bit_end = boxPlanes.end();
697
698	for (bit = boxPlanes.begin(); (bit != bit_end) && (*pit); ++ bit)
699	{
700	const int cf = (pit)->ClassifyPlane(bit, mEpsilon);
701
702	if (cf == Polygon3::COINCIDENT)
703	{
704	DEL_PTR(*pit);
705	//Debug << "coincident!!" << endl;
706	}
707	}
708	}
709
710	// remove deleted entries
711	for (int i = 0; i < (int)polys.size(); ++ i)
712	{
713	while (!polys[i] && (i < (int)polys.size()))
714	{
715	swap(polys[i], polys.back());
716	polys.pop_back();
717	}
718	}
719
720	CLEAR_CONTAINER(boxPolys);
721	}
722
723
724
725	void BspTree::Construct(const RayContainer &sampleRays,
726	AxisAlignedBox3 *forcedBoundingBox)
727	{
728	mStat.nodes = 1;
729	mBox.Initialize(); // initialise BSP tree bounding box
730
731	if (forcedBoundingBox)
732	mBox = *forcedBoundingBox;
733
734	PolygonContainer *polys = new PolygonContainer();
735	BoundedRayContainer *rays = new BoundedRayContainer();
736
737	RayContainer::const_iterator rit, rit_end = sampleRays.end();
738
739	// generate view cells
740	mGenerateViewCells = true;
741
742	long startTime = GetTime();
743
744	Debug << "** Extracting polygons from rays **\n";
745
746	std::map<Face , Polygon3 > facePolyMap;
747
748	//-- extract polygons intersected by the rays
749	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
750	{
751	Ray ray = rit;
752
753	// get ray-face intersection. Store polygon representing the rays together
754	// with rays intersecting the face.
755	if (!ray->intersections.empty())
756	{
757	MeshInstance obj = dynamic_cast<MeshInstance >(ray->intersections[0].mObject);
758
759	Mesh *mesh;
760	if (obj->Type() == Intersectable::TRANSFORMED_MESH_INSTANCE)
761	{
762	TransformedMeshInstance *tmobj =
763	dynamic_cast<TransformedMeshInstance *>(obj);
764
765	mesh = new Mesh();
766	tmobj->GetTransformedMesh(*mesh);
767	}
768	else // MeshInstance
769	{
770	mesh = obj->GetMesh();
771	}
772
773	Face *face = mesh->mFaces[ray->intersections[0].mFace];
774	std::map<Face , Polygon3 >::iterator it = facePolyMap.find(face);
775
776	if (it != facePolyMap.end())
777	{
778	//store rays if needed for heuristics
779	if (mSplitPlaneStrategy & BLOCKED_RAYS)
780	(*it).second->mPiercingRays.push_back(ray);
781	}
782	else
783	{
784	//store rays if needed for heuristics
785	Polygon3 *poly = new Polygon3(face, mesh);
786	poly->mParent = obj;
787	polys->push_back(poly);
788
789	if (mSplitPlaneStrategy & BLOCKED_RAYS)
790	poly->mPiercingRays.push_back(ray);
791
792	facePolyMap[face] = poly;
793	}
794
795	// cleanup
796	if (obj->Type() == Intersectable::TRANSFORMED_MESH_INSTANCE)
797	DEL_PTR(mesh);
798	}
799	}
800
801	facePolyMap.clear();
802
803	// compute bounding box
804	if (!forcedBoundingBox)
805	mBox.Include(*polys);
806
807	//-- store rays
808	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
809	{
810	Ray ray = rit;
811	ray->SetId(-1); // reset id
812
813	float minT, maxT;
814	if (mBox.GetRaySegment(*ray, minT, maxT))
815	rays->push_back(new BoundedRay(ray, minT, maxT));
816	}
817
818	// throw out bad polygons
819	PreprocessPolygons(*polys);
820
821	mStat.polys = (int)polys->size();
822
823	Debug << "** Finished polygon extraction **" << endl;
824	Debug << (int)polys->size() << " polys extracted from " << (int)sampleRays.size() << " rays" << endl;
825	Debug << "extraction time: " << TimeDiff(startTime, GetTime())*1e-3 << "s" << endl;
826
827	Construct(polys, rays);
828	}
829
830
831	void BspTree::Construct(const ObjectContainer &objects,
832	const RayContainer &sampleRays,
833	AxisAlignedBox3 *forcedBoundingBox)
834	{
835	mStat.nodes = 1;
836	mBox.Initialize(); // initialise BSP tree bounding box
837
838	if (forcedBoundingBox)
839	mBox = *forcedBoundingBox;
840
841	BoundedRayContainer *rays = new BoundedRayContainer();
842	PolygonContainer *polys = new PolygonContainer();
843
844	mGenerateViewCells = true;
845
846	// copy mesh instance polygons into one big polygon soup
847	mStat.polys = AddToPolygonSoup(objects, *polys, 0, !forcedBoundingBox);
848
849
850	RayContainer::const_iterator rit, rit_end = sampleRays.end();
851
852	//-- store rays
853	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
854	{
855	Ray ray = rit;
856	ray->SetId(-1); // reset id
857
858	float minT, maxT;
859	if (mBox.GetRaySegment(*ray, minT, maxT))
860	rays->push_back(new BoundedRay(ray, minT, maxT));
861	}
862
863	PreprocessPolygons(*polys);
864	Debug << "tree has " << (int)polys->size() << " polys, " << (int)sampleRays.size() << " rays" << endl;
865	Construct(polys, rays);
866	}
867
868
869	void BspTree::Construct(PolygonContainer polys, BoundedRayContainer rays)
870	{
871	BspTraversalStack tStack;
872
873	mRoot = new BspLeaf();
874
875	// constrruct root node geometry
876	BspNodeGeometry *geom = new BspNodeGeometry();
877	ConstructGeometry(mRoot, *geom);
878
879	BspTraversalData tData(mRoot,
880	polys,
881	0,
882	GetOrCreateOutOfBoundsCell(),
883	rays,
884	ComputePvsSize(*rays),
885	mUseAreaForPvs ? geom->GetArea() : geom->GetVolume(),
886	geom);
887
888	mTotalCost = tData.mPvs * tData.mProbability / mBox.GetVolume();
889	mTotalPvsSize = tData.mPvs;
890
891	mSubdivisionStats
892	<< "#ViewCells\n1\n" << endl
893	<< "#RenderCostDecrease\n0\n" << endl
894	<< "#TotalRenderCost\n" << mTotalCost << endl
895	<< "#AvgRenderCost\n" << mTotalPvsSize << endl;
896
897	tStack.push(tData);
898
899	// used for intermediate time measurements and progress
900	long interTime = GetTime();
901	int nleaves = 500;
902
903	mStat.Start();
904	cout << "Constructing bsp tree ...\n";
905	long startTime = GetTime();
906	while (!tStack.empty())
907	{
908	tData = tStack.top();
909
910	tStack.pop();
911
912	// subdivide leaf node
913	BspNode *r = Subdivide(tStack, tData);
914
915	if (r == mRoot)
916	Debug << "BSP tree construction time spent at root: "
917	<< TimeDiff(startTime, GetTime())*1e-3 << " secs" << endl;
918
919	if (mStat.Leaves() >= nleaves)
920	{
921	nleaves += 500;
922
923	cout << "leaves=" << mStat.Leaves() << endl;
924	Debug << "needed "
925	<< TimeDiff(interTime, GetTime())*1e-3
926	<< " secs to create 500 leaves" << endl;
927	interTime = GetTime();
928	}
929	}
930
931	cout << "finished\n";
932
933	mStat.Stop();
934	}
935
936
937	bool BspTree::TerminationCriteriaMet(const BspTraversalData &data) const
938	{
939	return
940	(((int)data.mPolygons->size() <= mTermMinPolys) \|\|
941	((int)data.mRays->size() <= mTermMinRays) \|\|
942	(data.mPvs <= mTermMinPvs) \|\|
943	(data.mProbability <= mTermMinProbability) \|\|
944	(data.mDepth >= mTermMaxDepth) \|\|
945	(mStat.Leaves() >= mMaxViewCells) \|\|
946	(data.GetAvgRayContribution() > mTermMaxRayContribution));
947	}
948
949
950	BspNode *BspTree::Subdivide(BspTraversalStack &tStack, BspTraversalData &tData)
951	{
952	//-- terminate traversal
953	if (TerminationCriteriaMet(tData))
954	{
955	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
956
957	BspViewCell *viewCell;
958
959	// generate new view cell for each leaf
960	if (mGenerateViewCells)
961	{
962	viewCell = new BspViewCell();
963	}
964	else
965	{
966	// add view cell to leaf
967	viewCell = dynamic_cast<BspViewCell *>(tData.mViewCell);
968	}
969
970	leaf->SetViewCell(viewCell);
971	viewCell->mLeaf = leaf;
972
973	//float probability = max(0.0f, tData.mProbability);
974	float probability = tData.mProbability;
975
976	if (mUseAreaForPvs)
977	viewCell->SetArea(probability);
978	else
979	viewCell->SetVolume(probability);
980
981	//-- add pvs
982	if (viewCell != mOutOfBoundsCell)
983	{
984	int conSamp = 0, sampCon = 0;
985	AddToPvs(leaf, *tData.mRays, conSamp, sampCon);
986
987	mStat.contributingSamples += conSamp;
988	mStat.sampleContributions += sampCon;
989	}
990
991	if (1)
992	EvaluateLeafStats(tData);
993
994	//-- clean up
995
996	// discard polygons
997	CLEAR_CONTAINER(*tData.mPolygons);
998	// discard rays
999	CLEAR_CONTAINER(*tData.mRays);
1000
1001	delete tData.mPolygons;
1002	delete tData.mRays;
1003	delete tData.mGeometry;
1004
1005	return leaf;
1006	}
1007
1008	//-- continue subdivision
1009	PolygonContainer coincident;
1010
1011	BspTraversalData tFrontData(NULL, new PolygonContainer(), tData.mDepth + 1, mOutOfBoundsCell,
1012	new BoundedRayContainer(), 0, 0, new BspNodeGeometry());
1013	BspTraversalData tBackData(NULL, new PolygonContainer(), tData.mDepth + 1, mOutOfBoundsCell,
1014	new BoundedRayContainer(), 0, 0, new BspNodeGeometry());
1015
1016
1017	// create new interior node and two leaf nodes
1018	BspInterior *interior =
1019	SubdivideNode(tData, tFrontData, tBackData, coincident);
1020
1021
1022	if (1)
1023	{
1024	int pvsData = tData.mPvs;
1025
1026	float cData = (float)pvsData * tData.mProbability;
1027	float cFront = (float)tFrontData.mPvs * tFrontData.mProbability;
1028	float cBack = (float)tBackData.mPvs * tBackData.mProbability;
1029
1030	float costDecr = (cFront + cBack - cData) / mBox.GetVolume();
1031
1032	mTotalCost += costDecr;
1033	mTotalPvsSize += tFrontData.mPvs + tBackData.mPvs - pvsData;
1034
1035	mSubdivisionStats
1036	<< "#ViewCells\n" << mStat.Leaves() << endl
1037	<< "#RenderCostDecrease\n" << -costDecr << endl
1038	<< "#TotalRenderCost\n" << mTotalCost << endl
1039	<< "#AvgRenderCost\n" << mTotalPvsSize / mStat.Leaves() << endl;
1040	}
1041
1042	// extract view cells from coincident polygons according to plane normal
1043	// only if front or back polygons are empty
1044	if (!mGenerateViewCells)
1045	{
1046	ExtractViewCells(tFrontData,
1047	tBackData,
1048	coincident,
1049	interior->mPlane);
1050	}
1051
1052	// don't need coincident polygons anymory
1053	CLEAR_CONTAINER(coincident);
1054
1055	// push the children on the stack
1056	tStack.push(tFrontData);
1057	tStack.push(tBackData);
1058
1059	// cleanup
1060	DEL_PTR(tData.mNode);
1061
1062	DEL_PTR(tData.mPolygons);
1063	DEL_PTR(tData.mRays);
1064	DEL_PTR(tData.mGeometry);
1065
1066	return interior;
1067	}
1068
1069
1070	void BspTree::ExtractViewCells(BspTraversalData &frontData,
1071	BspTraversalData &backData,
1072	const PolygonContainer &coincident,
1073	const Plane3 &splitPlane) const
1074	{
1075	// if not empty, tree is further subdivided => don't have to find view cell
1076	bool foundFront = !frontData.mPolygons->empty();
1077	bool foundBack = !frontData.mPolygons->empty();
1078
1079	PolygonContainer::const_iterator it =
1080	coincident.begin(), it_end = coincident.end();
1081
1082	//-- find first view cells in front and back leafs
1083	for (; !(foundFront && foundBack) && (it != it_end); ++ it)
1084	{
1085	if (DotProd((*it)->GetNormal(), splitPlane.mNormal) > 0)
1086	{
1087	backData.mViewCell = dynamic_cast<ViewCellLeaf >((it)->mParent);
1088	foundBack = true;
1089	}
1090	else
1091	{
1092	frontData.mViewCell = dynamic_cast<ViewCellLeaf >((it)->mParent);
1093	foundFront = true;
1094	}
1095	}
1096	}
1097
1098
1099	BspInterior *BspTree::SubdivideNode(BspTraversalData &tData,
1100	BspTraversalData &frontData,
1101	BspTraversalData &backData,
1102	PolygonContainer &coincident)
1103	{
1104	mStat.nodes += 2;
1105
1106	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
1107
1108	// select subdivision plane
1109	BspInterior *interior = new BspInterior(SelectPlane(leaf, tData));
1110
1111
1112	#ifdef _DEBUG
1113	Debug << interior << endl;
1114	#endif
1115
1116	// subdivide rays into front and back rays
1117	SplitRays(interior->mPlane, tData.mRays, frontData.mRays, *backData.mRays);
1118
1119	// subdivide polygons with plane
1120	mStat.polySplits += SplitPolygons(interior->GetPlane(),
1121	*tData.mPolygons,
1122	*frontData.mPolygons,
1123	*backData.mPolygons,
1124	coincident);
1125
1126
1127	// compute pvs
1128	frontData.mPvs = ComputePvsSize(*frontData.mRays);
1129	backData.mPvs = ComputePvsSize(*backData.mRays);
1130
1131	// split geometry and compute area
1132	if (1)
1133	{
1134	tData.mGeometry->SplitGeometry(*frontData.mGeometry,
1135	*backData.mGeometry,
1136	interior->mPlane,
1137	mBox,
1138	//0.000000000001);
1139	mEpsilon);
1140
1141
1142	if (mUseAreaForPvs)
1143	{
1144	frontData.mProbability = frontData.mGeometry->GetArea();
1145	backData.mProbability = backData.mGeometry->GetArea();
1146	}
1147	else
1148	{
1149	frontData.mProbability = frontData.mGeometry->GetVolume();
1150	backData.mProbability = tData.mProbability - frontData.mProbability;
1151	}
1152	}
1153
1154	//-- create front and back leaf
1155
1156	BspInterior *parent = leaf->GetParent();
1157
1158	// replace a link from node's parent
1159	if (!leaf->IsRoot())
1160	{
1161	parent->ReplaceChildLink(leaf, interior);
1162	interior->SetParent(parent);
1163	}
1164	else // new root
1165	{
1166	mRoot = interior;
1167	}
1168
1169	// and setup child links
1170	interior->SetupChildLinks(new BspLeaf(interior), new BspLeaf(interior));
1171
1172	frontData.mNode = interior->GetFront();
1173	backData.mNode = interior->GetBack();
1174
1175	interior->mTimeStamp = mTimeStamp ++;
1176
1177	//DEL_PTR(leaf);
1178	return interior;
1179	}
1180
1181
1182	void BspTree::SortSubdivisionCandidates(const PolygonContainer &polys,
1183	const int axis,
1184	vector<SortableEntry> &splitCandidates) const
1185	{
1186	splitCandidates.clear();
1187
1188	int requestedSize = 2 * (int)polys.size();
1189	// creates a sorted split candidates array
1190	splitCandidates.reserve(requestedSize);
1191
1192	PolygonContainer::const_iterator it, it_end = polys.end();
1193
1194	AxisAlignedBox3 box;
1195
1196	// insert all queries
1197	for(it = polys.begin(); it != it_end; ++ it)
1198	{
1199	box.Initialize();
1200	box.Include((it));
1201
1202	splitCandidates.push_back(SortableEntry(SortableEntry::POLY_MIN, box.Min(axis), *it));
1203	splitCandidates.push_back(SortableEntry(SortableEntry::POLY_MAX, box.Max(axis), *it));
1204	}
1205
1206	stable_sort(splitCandidates.begin(), splitCandidates.end());
1207	}
1208
1209
1210	float BspTree::BestCostRatio(const PolygonContainer &polys,
1211	const AxisAlignedBox3 &box,
1212	const int axis,
1213	float &position,
1214	int &objectsBack,
1215	int &objectsFront) const
1216	{
1217	vector<SortableEntry> splitCandidates;
1218
1219	SortSubdivisionCandidates(polys, axis, splitCandidates);
1220
1221	// go through the lists, count the number of objects left and right
1222	// and evaluate the following cost funcion:
1223	// C = ct_div_ci + (ol + or)/queries
1224
1225	int objectsLeft = 0, objectsRight = (int)polys.size();
1226
1227	float minBox = box.Min(axis);
1228	float maxBox = box.Max(axis);
1229	float boxArea = box.SurfaceArea();
1230
1231	float minBand = minBox + mSplitBorder * (maxBox - minBox);
1232	float maxBand = minBox + (1.0f - mSplitBorder) * (maxBox - minBox);
1233
1234	float minSum = 1e20f;
1235	vector<SortableEntry>::const_iterator ci, ci_end = splitCandidates.end();
1236
1237	for(ci = splitCandidates.begin(); ci != ci_end; ++ ci)
1238	{
1239	switch ((*ci).type)
1240	{
1241	case SortableEntry::POLY_MIN:
1242	++ objectsLeft;
1243	break;
1244	case SortableEntry::POLY_MAX:
1245	-- objectsRight;
1246	break;
1247	default:
1248	break;
1249	}
1250
1251	if ((ci).value > minBand && (ci).value < maxBand)
1252	{
1253	AxisAlignedBox3 lbox = box;
1254	AxisAlignedBox3 rbox = box;
1255	lbox.SetMax(axis, (*ci).value);
1256	rbox.SetMin(axis, (*ci).value);
1257
1258	const float sum = objectsLeft * lbox.SurfaceArea() +
1259	objectsRight * rbox.SurfaceArea();
1260
1261	if (sum < minSum)
1262	{
1263	minSum = sum;
1264	position = (*ci).value;
1265
1266	objectsBack = objectsLeft;
1267	objectsFront = objectsRight;
1268	}
1269	}
1270	}
1271
1272	const float oldCost = (float)polys.size();
1273	const float newCost = mAxisAlignedCtDivCi + minSum / boxArea;
1274	const float ratio = newCost / oldCost;
1275
1276
1277	#if 0
1278	Debug << "====================" << endl;
1279	Debug << "costRatio=" << ratio << " pos=" << position<<" t=" << (position - minBox)/(maxBox - minBox)
1280	<< "\t o=(" << objectsBack << "," << objectsFront << ")" << endl;
1281	#endif
1282	return ratio;
1283	}
1284
1285	bool BspTree::SelectAxisAlignedPlane(Plane3 &plane,
1286	const PolygonContainer &polys) const
1287	{
1288	AxisAlignedBox3 box;
1289	box.Initialize();
1290
1291	// create bounding box of region
1292	box.Include(polys);
1293
1294	int objectsBack = 0, objectsFront = 0;
1295	int axis = 0;
1296	float costRatio = MAX_FLOAT;
1297	Vector3 position;
1298
1299	//-- area subdivision
1300	for (int i = 0; i < 3; ++ i)
1301	{
1302	float p = 0;
1303	float r = BestCostRatio(polys, box, i, p, objectsBack, objectsFront);
1304
1305	if (r < costRatio)
1306	{
1307	costRatio = r;
1308	axis = i;
1309	position = p;
1310	}
1311	}
1312
1313	if (costRatio >= mMaxCostRatio)
1314	return false;
1315
1316	Vector3 norm(0,0,0); norm[axis] = 1.0f;
1317	plane = Plane3(norm, position);
1318
1319	return true;
1320	}
1321
1322
1323	Plane3 BspTree::SelectPlane(BspLeaf *leaf, BspTraversalData &data)
1324	{
1325	if ((!mMaxPolyCandidates \|\| data.mPolygons->empty()) &&
1326	(!mMaxRayCandidates \|\| data.mRays->empty()))
1327	{
1328	Debug << "Warning: No autopartition polygon candidate available\n";
1329
1330	// return axis aligned split
1331	AxisAlignedBox3 box;
1332	box.Initialize();
1333
1334	// create bounding box of region
1335	box.Include(*data.mPolygons);
1336
1337	const int axis = box.Size().DrivingAxis();
1338	const Vector3 position = (box.Min()[axis] + box.Max()[axis]) * 0.5f;
1339
1340	Vector3 norm(0,0,0); norm[axis] = 1.0f;
1341	return Plane3(norm, position);
1342	}
1343
1344	if ((mSplitPlaneStrategy & AXIS_ALIGNED) &&
1345	((int)data.mPolygons->size() > mTermMinPolysForAxisAligned) &&
1346	((int)data.mRays->size() > mTermMinRaysForAxisAligned) &&
1347	((mTermMinObjectsForAxisAligned < 0) \|\|
1348	(Polygon3::ParentObjectsSize(*data.mPolygons) > mTermMinObjectsForAxisAligned)))
1349	{
1350	Plane3 plane;
1351	if (SelectAxisAlignedPlane(plane, *data.mPolygons))
1352	return plane;
1353	}
1354
1355	// simplest strategy: just take next polygon
1356	if (mSplitPlaneStrategy & RANDOM_POLYGON)
1357	{
1358	if (!data.mPolygons->empty())
1359	{
1360	Polygon3 *nextPoly =
1361	(*data.mPolygons)[(int)RandomValue(0, (Real)((int)data.mPolygons->size() - 1))];
1362	return nextPoly->GetSupportingPlane();
1363	}
1364	else
1365	{
1366	const int candidateIdx = (int)RandomValue(0, (Real)((int)data.mRays->size() - 1));
1367	BoundedRay bRay = (data.mRays)[candidateIdx];
1368
1369	Ray *ray = bRay->mRay;
1370
1371	const Vector3 minPt = ray->Extrap(bRay->mMinT);
1372	const Vector3 maxPt = ray->Extrap(bRay->mMaxT);
1373
1374	const Vector3 pt = (maxPt + minPt) * 0.5;
1375
1376	const Vector3 normal = ray->GetDir();
1377
1378	return Plane3(normal, pt);
1379	}
1380
1381	return Plane3();
1382	}
1383
1384	// use heuristics to find appropriate plane
1385	return SelectPlaneHeuristics(leaf, data);
1386	}
1387
1388
1389	Plane3 BspTree::ChooseCandidatePlane(const BoundedRayContainer &rays) const
1390	{
1391	const int candidateIdx = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1392	BoundedRay *bRay = rays[candidateIdx];
1393	Ray *ray = bRay->mRay;
1394
1395	const Vector3 minPt = ray->Extrap(bRay->mMinT);
1396	const Vector3 maxPt = ray->Extrap(bRay->mMaxT);
1397
1398	const Vector3 pt = (maxPt + minPt) * 0.5;
1399
1400	const Vector3 normal = ray->GetDir();
1401
1402	return Plane3(normal, pt);
1403	}
1404
1405	Plane3 BspTree::ChooseCandidatePlane2(const BoundedRayContainer &rays) const
1406	{
1407	Vector3 pt[3];
1408	int idx[3];
1409	int cmaxT = 0;
1410	int cminT = 0;
1411	bool chooseMin = false;
1412
1413	for (int j = 0; j < 3; j ++)
1414	{
1415	idx[j] = (int)RandomValue(0, Real((int)rays.size() * 2 - 1));
1416
1417	if (idx[j] >= (int)rays.size())
1418	{
1419	idx[j] -= (int)rays.size();
1420	chooseMin = (cminT < 2);
1421	}
1422	else
1423	chooseMin = (cmaxT < 2);
1424
1425	BoundedRay *bRay = rays[idx[j]];
1426	pt[j] = chooseMin ? bRay->mRay->Extrap(bRay->mMinT) :
1427	bRay->mRay->Extrap(bRay->mMaxT);
1428	}
1429
1430	return Plane3(pt[0], pt[1], pt[2]);
1431	}
1432
1433	Plane3 BspTree::ChooseCandidatePlane3(const BoundedRayContainer &rays) const
1434	{
1435	Vector3 pt[3];
1436
1437	int idx1 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1438	int idx2 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1439
1440	// check if rays different
1441	if (idx1 == idx2)
1442	idx2 = (idx2 + 1) % (int)rays.size();
1443
1444	const BoundedRay *ray1 = rays[idx1];
1445	const BoundedRay *ray2 = rays[idx2];
1446
1447	// normal vector of the plane parallel to both lines
1448	const Vector3 norm =
1449	Normalize(CrossProd(ray1->mRay->GetDir(), ray2->mRay->GetDir()));
1450
1451	const Vector3 orig1 = ray1->mRay->Extrap(ray1->mMinT);
1452	const Vector3 orig2 = ray2->mRay->Extrap(ray2->mMinT);
1453
1454	// vector from line 1 to line 2
1455	const Vector3 vd = orig1 - orig2;
1456
1457	// project vector on normal to get distance
1458	const float dist = DotProd(vd, norm);
1459
1460	// point on plane lies halfway between the two planes
1461	const Vector3 planePt = orig1 + norm * dist * 0.5;
1462
1463	return Plane3(norm, planePt);
1464	}
1465
1466
1467	Plane3 BspTree::SelectPlaneHeuristics(BspLeaf *leaf, BspTraversalData &data)
1468	{
1469	float lowestCost = MAX_FLOAT;
1470	Plane3 bestPlane;
1471	// intermediate plane
1472	Plane3 plane;
1473
1474	const int limit = Min((int)data.mPolygons->size(), mMaxPolyCandidates);
1475	int maxIdx = (int)data.mPolygons->size();
1476
1477	for (int i = 0; i < limit; ++ i)
1478	{
1479	// assure that no index is taken twice
1480	const int candidateIdx = (int)RandomValue(0, (Real)(-- maxIdx));
1481
1482	Polygon3 poly = (data.mPolygons)[candidateIdx];
1483
1484	// swap candidate to the end to avoid testing same plane
1485	std::swap((data.mPolygons)[maxIdx], (data.mPolygons)[candidateIdx]);
1486	//Polygon3 poly = (data.mPolygons)[(int)RandomValue(0, (int)polys.size() - 1)];
1487
1488	// evaluate current candidate
1489	const float candidateCost =
1490	SplitPlaneCost(poly->GetSupportingPlane(), data);
1491
1492	if (candidateCost < lowestCost)
1493	{
1494	bestPlane = poly->GetSupportingPlane();
1495	lowestCost = candidateCost;
1496	}
1497	}
1498
1499	//-- choose candidate planes extracted from rays
1500	for (int i = 0; i < mMaxRayCandidates; ++ i)
1501	{
1502	plane = ChooseCandidatePlane3(*data.mRays);
1503	const float candidateCost = SplitPlaneCost(plane, data);
1504
1505	if (candidateCost < lowestCost)
1506	{
1507	bestPlane = plane;
1508	lowestCost = candidateCost;
1509	}
1510	}
1511
1512	#ifdef _DEBUG
1513	Debug << "plane lowest cost: " << lowestCost << endl;
1514	#endif
1515
1516	return bestPlane;
1517	}
1518
1519
1520	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1521	const PolygonContainer &polys) const
1522	{
1523	float val = 0;
1524
1525	float sumBalancedPolys = 0;
1526	float sumSplits = 0;
1527	float sumPolyArea = 0;
1528	float sumBalancedViewCells = 0;
1529	float sumBlockedRays = 0;
1530	float totalBlockedRays = 0;
1531	//float totalArea = 0;
1532	int totalViewCells = 0;
1533
1534	// need three unique ids for each type of view cell
1535	// for balanced view cells criterium
1536	ViewCell::NewMail();
1537	const int backId = ViewCell::sMailId;
1538	ViewCell::NewMail();
1539	const int frontId = ViewCell::sMailId;
1540	ViewCell::NewMail();
1541	const int frontAndBackId = ViewCell::sMailId;
1542
1543	bool useRand;
1544	int limit;
1545
1546	// choose test polyongs randomly if over threshold
1547	if ((int)polys.size() > mMaxTests)
1548	{
1549	useRand = true;
1550	limit = mMaxTests;
1551	}
1552	else
1553	{
1554	useRand = false;
1555	limit = (int)polys.size();
1556	}
1557
1558	for (int i = 0; i < limit; ++ i)
1559	{
1560	const int testIdx = useRand ? (int)RandomValue(0, (Real)(limit - 1)) : i;
1561
1562	Polygon3 *poly = polys[testIdx];
1563
1564	const int classification =
1565	poly->ClassifyPlane(candidatePlane, mEpsilon);
1566
1567	if (mSplitPlaneStrategy & BALANCED_POLYS)
1568	sumBalancedPolys += sBalancedPolysTable[classification];
1569
1570	if (mSplitPlaneStrategy & LEAST_SPLITS)
1571	sumSplits += sLeastPolySplitsTable[classification];
1572
1573	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
1574	{
1575	if (classification == Polygon3::COINCIDENT)
1576	sumPolyArea += poly->GetArea();
1577	//totalArea += area;
1578	}
1579
1580	if (mSplitPlaneStrategy & BLOCKED_RAYS)
1581	{
1582	const float blockedRays = (float)poly->mPiercingRays.size();
1583
1584	if (classification == Polygon3::COINCIDENT)
1585	sumBlockedRays += blockedRays;
1586
1587	totalBlockedRays += blockedRays;
1588	}
1589
1590	// assign view cells to back or front according to classificaion
1591	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
1592	{
1593	MeshInstance *viewCell = poly->mParent;
1594
1595	// assure that we only count a view cell
1596	// once for the front and once for the back side of the plane
1597	if (classification == Polygon3::FRONT_SIDE)
1598	{
1599	if ((viewCell->mMailbox != frontId) &&
1600	(viewCell->mMailbox != frontAndBackId))
1601	{
1602	sumBalancedViewCells += 1.0;
1603
1604	if (viewCell->mMailbox != backId)
1605	viewCell->mMailbox = frontId;
1606	else
1607	viewCell->mMailbox = frontAndBackId;
1608
1609	++ totalViewCells;
1610	}
1611	}
1612	else if (classification == Polygon3::BACK_SIDE)
1613	{
1614	if ((viewCell->mMailbox != backId) &&
1615	(viewCell->mMailbox != frontAndBackId))
1616	{
1617	sumBalancedViewCells -= 1.0;
1618
1619	if (viewCell->mMailbox != frontId)
1620	viewCell->mMailbox = backId;
1621	else
1622	viewCell->mMailbox = frontAndBackId;
1623
1624	++ totalViewCells;
1625	}
1626	}
1627	}
1628	}
1629
1630	const float polysSize = (float)polys.size() + Limits::Small;
1631
1632	// all values should be approx. between 0 and 1 so they can be combined
1633	// and scaled with the factors according to their importance
1634	if (mSplitPlaneStrategy & BALANCED_POLYS)
1635	val += mBalancedPolysFactor * fabs(sumBalancedPolys) / polysSize;
1636
1637	if (mSplitPlaneStrategy & LEAST_SPLITS)
1638	val += mLeastSplitsFactor * sumSplits / polysSize;
1639
1640	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
1641	// HACK: polys.size should be total area so scaling is between 0 and 1
1642	val += mLargestPolyAreaFactor * (float)polys.size() / sumPolyArea;
1643
1644	if (mSplitPlaneStrategy & BLOCKED_RAYS)
1645	if (totalBlockedRays != 0)
1646	val += mBlockedRaysFactor * (totalBlockedRays - sumBlockedRays) / totalBlockedRays;
1647
1648	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
1649	val += mBalancedViewCellsFactor * fabs(sumBalancedViewCells) /
1650	((float)totalViewCells + Limits::Small);
1651
1652	return val;
1653	}
1654
1655
1656	inline void BspTree::GenerateUniqueIdsForPvs()
1657	{
1658	Intersectable::NewMail(); sBackId = Intersectable::sMailId;
1659	Intersectable::NewMail(); sFrontId = Intersectable::sMailId;
1660	Intersectable::NewMail(); sFrontAndBackId = Intersectable::sMailId;
1661	}
1662
1663
1664	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1665	const BoundedRayContainer &rays,
1666	const int pvs,
1667	const float probability,
1668	const BspNodeGeometry &cell) const
1669	{
1670	float val = 0;
1671
1672	float sumBalancedRays = 0;
1673	float sumRaySplits = 0;
1674
1675	int frontPvs = 0;
1676	int backPvs = 0;
1677
1678	// probability that view point lies in child
1679	float pOverall = 0;
1680	float pFront = 0;
1681	float pBack = 0;
1682
1683	const bool pvsUseLen = false;
1684
1685
1686	if (mSplitPlaneStrategy & PVS)
1687	{
1688	// create unique ids for pvs heuristics
1689	GenerateUniqueIdsForPvs();
1690
1691	// construct child geometry with regard to the candidate split plane
1692	BspNodeGeometry geomFront;
1693	BspNodeGeometry geomBack;
1694
1695	const bool splitSuccessFull =
1696	cell.SplitGeometry(geomFront,
1697	geomBack,
1698	candidatePlane,
1699	mBox,
1700	mEpsilon);
1701
1702	if (mUseAreaForPvs)
1703	{
1704	pFront = geomFront.GetArea();
1705	pBack = geomBack.GetArea();
1706	}
1707	else
1708	{
1709	pFront = geomFront.GetVolume();
1710	pBack = pOverall - pFront;
1711	}
1712
1713
1714	// give penalty to unbalanced split
1715	if (1 &&
1716	(!splitSuccessFull \|\| (pFront <= 0) \|\| (pBack <= 0) \|\|
1717	!geomFront.Valid() \|\| !geomBack.Valid()))
1718	{
1719	//Debug << "error f: " << pFront << " b: " << pBack << endl;
1720	return 99999.9f;
1721	}
1722
1723	pOverall = probability;
1724	}
1725
1726	bool useRand;
1727	int limit;
1728
1729	// choose test polyongs randomly if over threshold
1730	if ((int)rays.size() > mMaxTests)
1731	{
1732	useRand = true;
1733	limit = mMaxTests;
1734	}
1735	else
1736	{
1737	useRand = false;
1738	limit = (int)rays.size();
1739	}
1740
1741	for (int i = 0; i < limit; ++ i)
1742	{
1743	const int testIdx = useRand ? (int)RandomValue(0, (Real)(limit - 1)) : i;
1744
1745	BoundedRay *bRay = rays[testIdx];
1746
1747	Ray *ray = bRay->mRay;
1748	const float minT = bRay->mMinT;
1749	const float maxT = bRay->mMaxT;
1750
1751	Vector3 entP, extP;
1752
1753	const int cf =
1754	ray->ClassifyPlane(candidatePlane, minT, maxT, entP, extP);
1755
1756	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
1757	{
1758	sumBalancedRays += sBalancedRaysTable[cf];
1759	}
1760
1761	if (mSplitPlaneStrategy & BALANCED_RAYS)
1762	{
1763	sumRaySplits += sLeastRaySplitsTable[cf];
1764	}
1765
1766	if (mSplitPlaneStrategy & PVS)
1767	{
1768	// in case the ray intersects an object
1769	// assure that we only count the object
1770	// once for the front and once for the back side of the plane
1771
1772	// add the termination object
1773	if (!ray->intersections.empty())
1774	AddObjToPvs(ray->intersections[0].mObject, cf, frontPvs, backPvs);
1775
1776	// add the source object
1777	AddObjToPvs(ray->sourceObject.mObject, cf, frontPvs, backPvs);
1778	}
1779	}
1780
1781	const float raysSize = (float)rays.size() + Limits::Small;
1782
1783	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
1784	val += mLeastRaySplitsFactor * sumRaySplits / raysSize;
1785
1786	if (mSplitPlaneStrategy & BALANCED_RAYS)
1787	val += mBalancedRaysFactor * fabs(sumBalancedRays) / raysSize;
1788
1789	const float denom = pOverall * (float)pvs + Limits::Small;
1790
1791	if (mSplitPlaneStrategy & PVS)
1792	{
1793	val += mPvsFactor * (frontPvs * pFront + (backPvs * pBack)) / denom;
1794	}
1795
1796
1797	#ifdef _DEBUG
1798	Debug << "totalpvs: " << pvs << " ptotal: " << pOverall
1799	<< " frontpvs: " << frontPvs << " pFront: " << pFront
1800	<< " backpvs: " << backPvs << " pBack: " << pBack << endl << endl;
1801	#endif
1802
1803	return val;
1804	}
1805
1806	void BspTree::AddObjToPvs(Intersectable *obj,
1807	const int cf,
1808	int &frontPvs,
1809	int &backPvs) const
1810	{
1811	if (!obj)
1812	return;
1813	// TODO: does this really belong to no pvs?
1814	//if (cf == Ray::COINCIDENT) return;
1815
1816	// object belongs to both PVS
1817	const bool bothSides = (cf == Ray::FRONT_BACK) \|\|
1818	(cf == Ray::BACK_FRONT) \|\|
1819	(cf == Ray::COINCIDENT);
1820
1821	if ((cf == Ray::FRONT) \|\| bothSides)
1822	{
1823	if ((obj->mMailbox != sFrontId) &&
1824	(obj->mMailbox != sFrontAndBackId))
1825	{
1826	++ frontPvs;
1827
1828	if (obj->mMailbox == sBackId)
1829	obj->mMailbox = sFrontAndBackId;
1830	else
1831	obj->mMailbox = sFrontId;
1832	}
1833	}
1834
1835	if ((cf == Ray::BACK) \|\| bothSides)
1836	{
1837	if ((obj->mMailbox != sBackId) &&
1838	(obj->mMailbox != sFrontAndBackId))
1839	{
1840	++ backPvs;
1841
1842	if (obj->mMailbox == sFrontId)
1843	obj->mMailbox = sFrontAndBackId;
1844	else
1845	obj->mMailbox = sBackId;
1846	}
1847	}
1848	}
1849
1850
1851	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1852	BspTraversalData &data) const
1853	{
1854	float val = 0;
1855
1856	if (mSplitPlaneStrategy & VERTICAL_AXIS)
1857	{
1858	Vector3 tinyAxis(0,0,0); tinyAxis[mBox.Size().TinyAxis()] = 1.0f;
1859	// we put a penalty on the dot product between the "tiny" vertical axis
1860	// and the split plane axis
1861	val += mVerticalSplitsFactor *
1862	fabs(DotProd(candidatePlane.mNormal, tinyAxis));
1863	}
1864
1865	// the following criteria loop over all polygons to find the cost value
1866	if ((mSplitPlaneStrategy & BALANCED_POLYS) \|\|
1867	(mSplitPlaneStrategy & LEAST_SPLITS) \|\|
1868	(mSplitPlaneStrategy & LARGEST_POLY_AREA) \|\|
1869	(mSplitPlaneStrategy & BALANCED_VIEW_CELLS) \|\|
1870	(mSplitPlaneStrategy & BLOCKED_RAYS))
1871	{
1872	val += SplitPlaneCost(candidatePlane, *data.mPolygons);
1873	}
1874
1875	// the following criteria loop over all rays to find the cost value
1876	if ((mSplitPlaneStrategy & BALANCED_RAYS) \|\|
1877	(mSplitPlaneStrategy & LEAST_RAY_SPLITS) \|\|
1878	(mSplitPlaneStrategy & PVS))
1879	{
1880	val += SplitPlaneCost(candidatePlane, *data.mRays, data.mPvs,
1881	data.mProbability, *data.mGeometry);
1882	}
1883
1884	// return linear combination of the sums
1885	return val;
1886	}
1887
1888	void BspTree::CollectLeaves(vector<BspLeaf *> &leaves) const
1889	{
1890	stack<BspNode *> nodeStack;
1891	nodeStack.push(mRoot);
1892
1893	while (!nodeStack.empty())
1894	{
1895	BspNode *node = nodeStack.top();
1896
1897	nodeStack.pop();
1898
1899	if (node->IsLeaf())
1900	{
1901	BspLeaf leaf = (BspLeaf )node;
1902	leaves.push_back(leaf);
1903	}
1904	else
1905	{
1906	BspInterior interior = dynamic_cast<BspInterior >(node);
1907
1908	nodeStack.push(interior->GetBack());
1909	nodeStack.push(interior->GetFront());
1910	}
1911	}
1912	}
1913
1914
1915	AxisAlignedBox3 BspTree::GetBoundingBox() const
1916	{
1917	return mBox;
1918	}
1919
1920
1921	void BspTree::EvaluateLeafStats(const BspTraversalData &data)
1922	{
1923	// the node became a leaf -> evaluate stats for leafs
1924	BspLeaf leaf = dynamic_cast<BspLeaf >(data.mNode);
1925
1926	// store maximal and minimal depth
1927	if (data.mDepth > mStat.maxDepth)
1928	mStat.maxDepth = data.mDepth;
1929
1930	if (data.mDepth < mStat.minDepth)
1931	mStat.minDepth = data.mDepth;
1932
1933	// accumulate depth to compute average depth
1934	mStat.accumDepth += data.mDepth;
1935	// accumulate rays to compute rays / leaf
1936	mStat.accumRays += (int)data.mRays->size();
1937
1938	if (data.mDepth >= mTermMaxDepth)
1939	++ mStat.maxDepthNodes;
1940
1941	if (data.mPvs < mTermMinPvs)
1942	++ mStat.minPvsNodes;
1943
1944	if ((int)data.mRays->size() < mTermMinRays)
1945	++ mStat.minRaysNodes;
1946
1947	if (data.GetAvgRayContribution() > mTermMaxRayContribution)
1948	++ mStat.maxRayContribNodes;
1949
1950	if (data.mProbability <= mTermMinProbability)
1951	++ mStat.minProbabilityNodes;
1952
1953	#ifdef _DEBUG
1954	Debug << "BSP stats: "
1955	<< "Depth: " << data.mDepth << " (max: " << mTermMaxDepth << "), "
1956	<< "PVS: " << data.mPvs << " (min: " << mTermMinPvs << "), "
1957	<< "Probability: " << data.mProbability << " (min: " << mTermMinProbability << "), "
1958	<< "#polygons: " << (int)data.mPolygons->size() << " (max: " << mTermMinPolys << "), "
1959	<< "#rays: " << (int)data.mRays->size() << " (max: " << mTermMinRays << "), "
1960	<< "#pvs: " << leaf->GetViewCell()->GetPvs().CountObjectsInPvs() << "=, "
1961	<< "#avg ray contrib (pvs): " << (float)data.mPvs / (float)data.mRays->size() << endl;
1962	#endif
1963	}
1964
1965
1966	int BspTree::_CastRay(Ray &ray)
1967	{
1968	int hits = 0;
1969
1970	stack<BspRayTraversalData> tStack;
1971
1972	float maxt, mint;
1973
1974	if (!mBox.GetRaySegment(ray, mint, maxt))
1975	return 0;
1976
1977	ViewCell::NewMail();
1978
1979	Vector3 entp = ray.Extrap(mint);
1980	Vector3 extp = ray.Extrap(maxt);
1981
1982	BspNode *node = mRoot;
1983	BspNode *farChild = NULL;
1984
1985	while (1)
1986	{
1987	if (!node->IsLeaf())
1988	{
1989	BspInterior in = dynamic_cast<BspInterior >(node);
1990
1991	Plane3 splitPlane = in->GetPlane();
1992	const int entSide = splitPlane.Side(entp);
1993	const int extSide = splitPlane.Side(extp);
1994
1995	if (entSide < 0)
1996	{
1997	node = in->GetBack();
1998
1999	if(extSide <= 0) // plane does not split ray => no far child
2000	continue;
2001
2002	farChild = in->GetFront(); // plane splits ray
2003
2004	} else if (entSide > 0)
2005	{
2006	node = in->GetFront();
2007
2008	if (extSide >= 0) // plane does not split ray => no far child
2009	continue;
2010
2011	farChild = in->GetBack(); // plane splits ray
2012	}
2013	else // ray and plane are coincident
2014	{
2015	// WHAT TO DO IN THIS CASE ?
2016	//break;
2017	node = in->GetFront();
2018	continue;
2019	}
2020
2021	// push data for far child
2022	tStack.push(BspRayTraversalData(farChild, extp, maxt));
2023
2024	// find intersection of ray segment with plane
2025	float t;
2026	extp = splitPlane.FindIntersection(ray.GetLoc(), extp, &t);
2027	maxt *= t;
2028
2029	} else // reached leaf => intersection with view cell
2030	{
2031	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2032
2033	if (!leaf->mViewCell->Mailed())
2034	{
2035	//ray.bspIntersections.push_back(Ray::BspIntersection(maxt, leaf));
2036	leaf->mViewCell->Mail();
2037	++ hits;
2038	}
2039
2040	//-- fetch the next far child from the stack
2041	if (tStack.empty())
2042	break;
2043
2044	entp = extp;
2045	mint = maxt; // NOTE: need this?
2046
2047	if (ray.GetType() == Ray::LINE_SEGMENT && mint > 1.0f)
2048	break;
2049
2050	BspRayTraversalData &s = tStack.top();
2051
2052	node = s.mNode;
2053	extp = s.mExitPoint;
2054	maxt = s.mMaxT;
2055
2056	tStack.pop();
2057	}
2058	}
2059
2060	return hits;
2061	}
2062
2063
2064	int BspTree::CastLineSegment(const Vector3 &origin,
2065	const Vector3 &termination,
2066	ViewCellContainer &viewcells)
2067	{
2068	int hits = 0;
2069	stack<BspRayTraversalData> tStack;
2070
2071	float mint = 0.0f, maxt = 1.0f;
2072
2073	//ViewCell::NewMail();
2074
2075	Vector3 entp = origin;
2076	Vector3 extp = termination;
2077
2078	BspNode *node = mRoot;
2079	BspNode *farChild = NULL;
2080
2081
2082	const float thresh = 1 ? 1e-6f : 0.0f;
2083
2084	while (1)
2085	{
2086	if (!node->IsLeaf())
2087	{
2088	BspInterior in = dynamic_cast<BspInterior >(node);
2089
2090	Plane3 splitPlane = in->GetPlane();
2091
2092	const int entSide = splitPlane.Side(entp, thresh);
2093	const int extSide = splitPlane.Side(extp, thresh);
2094
2095	if (entSide < 0)
2096	{
2097	node = in->GetBack();
2098
2099	// plane does not split ray => no far child
2100	if (extSide <= 0)
2101	continue;
2102
2103	farChild = in->GetFront(); // plane splits ray
2104	}
2105	else if (entSide > 0)
2106	{
2107	node = in->GetFront();
2108
2109	if (extSide >= 0) // plane does not split ray => no far child
2110	continue;
2111
2112	farChild = in->GetBack(); // plane splits ray
2113	}
2114	else // one of the ray end points is on the plane
2115	{ // NOTE: what to do if ray is coincident with plane?
2116	if (extSide < 0)
2117	node = in->GetBack();
2118	else //if (extSide > 0)
2119	node = in->GetFront();
2120	//else break; // coincident => count no intersections
2121
2122	continue; // no far child
2123	}
2124
2125	// push data for far child
2126	tStack.push(BspRayTraversalData(farChild, extp, maxt));
2127
2128	// find intersection of ray segment with plane
2129	float t;
2130	extp = splitPlane.FindIntersection(origin, extp, &t);
2131	maxt *= t;
2132	}
2133	else
2134	{
2135	// reached leaf => intersection with view cell
2136	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2137
2138	if (!leaf->mViewCell->Mailed())
2139	{
2140	viewcells.push_back(leaf->mViewCell);
2141	leaf->mViewCell->Mail();
2142	++ hits;
2143	}
2144
2145	//-- fetch the next far child from the stack
2146	if (tStack.empty())
2147	break;
2148
2149	entp = extp;
2150	mint = maxt; // NOTE: need this?
2151
2152	BspRayTraversalData &s = tStack.top();
2153
2154	node = s.mNode;
2155	extp = s.mExitPoint;
2156	maxt = s.mMaxT;
2157
2158	tStack.pop();
2159	}
2160	}
2161
2162	return hits;
2163	}
2164
2165
2166	void BspTree::CollectViewCells(ViewCellContainer &viewCells) const
2167	{
2168	stack<BspNode *> nodeStack;
2169	nodeStack.push(mRoot);
2170
2171	ViewCell::NewMail();
2172
2173	while (!nodeStack.empty())
2174	{
2175	BspNode *node = nodeStack.top();
2176	nodeStack.pop();
2177
2178	if (node->IsLeaf())
2179	{
2180	ViewCellLeaf viewCell = dynamic_cast<BspLeaf >(node)->mViewCell;
2181
2182	if (!viewCell->Mailed())
2183	{
2184	viewCell->Mail();
2185	viewCells.push_back(viewCell);
2186	}
2187	}
2188	else
2189	{
2190	BspInterior interior = dynamic_cast<BspInterior >(node);
2191
2192	nodeStack.push(interior->GetFront());
2193	nodeStack.push(interior->GetBack());
2194	}
2195	}
2196	}
2197
2198
2199	BspTreeStatistics &BspTree::GetStat()
2200	{
2201	return mStat;
2202	}
2203
2204
2205	float BspTree::AccumulatedRayLength(BoundedRayContainer &rays) const
2206	{
2207	float len = 0;
2208
2209	BoundedRayContainer::const_iterator it, it_end = rays.end();
2210
2211	for (it = rays.begin(); it != it_end; ++ it)
2212	{
2213	len += SqrDistance((it)->mRay->Extrap((it)->mMinT),
2214	(it)->mRay->Extrap((it)->mMaxT));
2215	}
2216
2217	return len;
2218	}
2219
2220
2221	int BspTree::SplitRays(const Plane3 &plane,
2222	BoundedRayContainer &rays,
2223	BoundedRayContainer &frontRays,
2224	BoundedRayContainer &backRays)
2225	{
2226	int splits = 0;
2227
2228	while (!rays.empty())
2229	{
2230	BoundedRay *bRay = rays.back();
2231	Ray *ray = bRay->mRay;
2232	float minT = bRay->mMinT;
2233	float maxT = bRay->mMaxT;
2234
2235	rays.pop_back();
2236
2237	Vector3 entP, extP;
2238
2239	const int cf =
2240	ray->ClassifyPlane(plane, minT, maxT, entP, extP);
2241
2242	// set id to ray classification
2243	ray->SetId(cf);
2244
2245	switch (cf)
2246	{
2247	case Ray::COINCIDENT: // TODO: should really discard ray?
2248	frontRays.push_back(bRay);
2249	//DEL_PTR(bRay);
2250	break;
2251	case Ray::BACK:
2252	backRays.push_back(bRay);
2253	break;
2254	case Ray::FRONT:
2255	frontRays.push_back(bRay);
2256	break;
2257	case Ray::FRONT_BACK:
2258	{
2259	// find intersection of ray segment with plane
2260	const float t = plane.FindT(ray->GetLoc(), extP);
2261
2262	const float newT = t * maxT;
2263
2264	frontRays.push_back(new BoundedRay(ray, minT, newT));
2265	backRays.push_back(new BoundedRay(ray, newT, maxT));
2266
2267	DEL_PTR(bRay);
2268	}
2269	break;
2270	case Ray::BACK_FRONT:
2271	{
2272	// find intersection of ray segment with plane
2273	const float t = plane.FindT(ray->GetLoc(), extP);
2274	const float newT = t * bRay->mMaxT;
2275
2276	backRays.push_back(new BoundedRay(ray, minT, newT));
2277	frontRays.push_back(new BoundedRay(ray, newT, maxT));
2278
2279	DEL_PTR(bRay);
2280
2281	++ splits;
2282	}
2283	break;
2284	default:
2285	Debug << "Should not come here 4" << endl;
2286	break;
2287	}
2288	}
2289
2290	return splits;
2291	}
2292
2293	void BspTree::ExtractHalfSpaces(BspNode *n, vector<Plane3> &halfSpaces) const
2294	{
2295	BspNode *lastNode;
2296
2297	do
2298	{
2299	lastNode = n;
2300
2301	// want to get planes defining geometry of this node => don't take
2302	// split plane of node itself
2303	n = n->GetParent();
2304
2305	if (n)
2306	{
2307	BspInterior interior = dynamic_cast<BspInterior >(n);
2308	Plane3 halfSpace = dynamic_cast<BspInterior *>(interior)->GetPlane();
2309
2310	if (interior->GetBack() != lastNode)
2311	halfSpace.ReverseOrientation();
2312
2313	halfSpaces.push_back(halfSpace);
2314	}
2315	}
2316	while (n);
2317	}
2318
2319
2320
2321	void BspTree::ConstructGeometry(ViewCell *vc,
2322	BspNodeGeometry &vcGeom) const
2323	{
2324	ViewCellContainer leaves;
2325	mViewCellsTree->CollectLeaves(vc, leaves);
2326
2327	ViewCellContainer::const_iterator it, it_end = leaves.end();
2328
2329	for (it = leaves.begin(); it != it_end; ++ it)
2330	{
2331	BspLeaf l = dynamic_cast<BspViewCell >(*it)->mLeaf;
2332	ConstructGeometry(l, vcGeom);
2333	}
2334	}
2335
2336
2337	void BspTree::ConstructGeometry(BspNode *n,
2338	BspNodeGeometry &geom) const
2339	{
2340	vector<Plane3> halfSpaces;
2341	ExtractHalfSpaces(n, halfSpaces);
2342
2343	PolygonContainer candidatePolys;
2344	vector<Plane3> candidatePlanes;
2345
2346	vector<Plane3>::const_iterator pit, pit_end = halfSpaces.end();
2347
2348	// bounded planes are added to the polygons
2349	for (pit = halfSpaces.begin(); pit != pit_end; ++ pit)
2350	{
2351	Polygon3 p = GetBoundingBox().CrossSection(pit);
2352
2353	if (p->Valid(mEpsilon))
2354	{
2355	candidatePolys.push_back(p);
2356	candidatePlanes.push_back(*pit);
2357	}
2358	}
2359
2360	// add faces of bounding box (also could be faces of the cell)
2361	for (int i = 0; i < 6; ++ i)
2362	{
2363	VertexContainer vertices;
2364
2365	for (int j = 0; j < 4; ++ j)
2366	vertices.push_back(mBox.GetFace(i).mVertices[j]);
2367
2368	Polygon3 *poly = new Polygon3(vertices);
2369
2370	candidatePolys.push_back(poly);
2371	candidatePlanes.push_back(poly->GetSupportingPlane());
2372	}
2373
2374	for (int i = 0; i < (int)candidatePolys.size(); ++ i)
2375	{
2376	// polygon is split by all other planes
2377	for (int j = 0; (j < (int)halfSpaces.size()) && candidatePolys[i]; ++ j)
2378	{
2379	if (i == j) // polygon and plane are coincident
2380	continue;
2381
2382	VertexContainer splitPts;
2383	Polygon3 frontPoly, backPoly;
2384
2385	const int cf =
2386	candidatePolys[i]->ClassifyPlane(halfSpaces[j],
2387	mEpsilon);
2388
2389	switch (cf)
2390	{
2391	case Polygon3::SPLIT:
2392	frontPoly = new Polygon3();
2393	backPoly = new Polygon3();
2394
2395	candidatePolys[i]->Split(halfSpaces[j],
2396	*frontPoly,
2397	*backPoly,
2398	mEpsilon);
2399
2400	DEL_PTR(candidatePolys[i]);
2401
2402	if (backPoly->Valid(mEpsilon))
2403	candidatePolys[i] = backPoly;
2404	else
2405	DEL_PTR(backPoly);
2406
2407	// outside, don't need this
2408	DEL_PTR(frontPoly);
2409	break;
2410	// polygon outside of halfspace
2411	case Polygon3::FRONT_SIDE:
2412	DEL_PTR(candidatePolys[i]);
2413	break;
2414	// just take polygon as it is
2415	case Polygon3::BACK_SIDE:
2416	case Polygon3::COINCIDENT:
2417	default:
2418	break;
2419	}
2420	}
2421
2422	if (candidatePolys[i])
2423	{
2424	geom.Add(candidatePolys[i], candidatePlanes[i]);
2425	}
2426	}
2427	}
2428
2429
2430	void BspTree::SetViewCellsManager(ViewCellsManager *vcm)
2431	{
2432	mViewCellsManager = vcm;
2433	}
2434
2435
2436	typedef pair<BspNode , BspNodeGeometry > bspNodePair;
2437
2438
2439	int BspTree::FindNeighbors(BspNode *n,
2440	vector<BspLeaf *> &neighbors,
2441	const bool onlyUnmailed) const
2442	{
2443	stack<bspNodePair> nodeStack;
2444
2445	BspNodeGeometry nodeGeom;
2446	ConstructGeometry(n, nodeGeom);
2447
2448	// split planes from the root to this node
2449	// needed to verify that we found neighbor leaf
2450	// TODO: really needed?
2451	vector<Plane3> halfSpaces;
2452	ExtractHalfSpaces(n, halfSpaces);
2453
2454
2455	BspNodeGeometry *rgeom = new BspNodeGeometry();
2456	ConstructGeometry(mRoot, *rgeom);
2457
2458	nodeStack.push(bspNodePair(mRoot, rgeom));
2459
2460	while (!nodeStack.empty())
2461	{
2462	BspNode *node = nodeStack.top().first;
2463	BspNodeGeometry *geom = nodeStack.top().second;
2464
2465	nodeStack.pop();
2466
2467	if (node->IsLeaf())
2468	{
2469	// test if this leaf is in valid view space
2470	if (node->TreeValid() &&
2471	(node != n) &&
2472	(!onlyUnmailed \|\| !node->Mailed()))
2473	{
2474	bool isAdjacent = true;
2475
2476	if (1)
2477	{
2478	// test all planes of current node if still adjacent
2479	for (int i = 0; (i < halfSpaces.size()) && isAdjacent; ++ i)
2480	{
2481	const int cf =
2482	Polygon3::ClassifyPlane(geom->GetPolys(),
2483	halfSpaces[i],
2484	mEpsilon);
2485
2486	if (cf == Polygon3::FRONT_SIDE)
2487	{
2488	isAdjacent = false;
2489	}
2490	}
2491	}
2492	else
2493	{
2494	// TODO: why is this wrong??
2495	// test all planes of current node if still adjacent
2496	for (int i = 0; (i < nodeGeom.Size()) && isAdjacent; ++ i)
2497	{
2498	Polygon3 *poly = nodeGeom.GetPolys()[i];
2499
2500	const int cf =
2501	Polygon3::ClassifyPlane(geom->GetPolys(),
2502	poly->GetSupportingPlane(),
2503	mEpsilon);
2504
2505	if (cf == Polygon3::FRONT_SIDE)
2506	{
2507	isAdjacent = false;
2508	}
2509	}
2510	}
2511	// neighbor was found
2512	if (isAdjacent)
2513	{
2514	neighbors.push_back(dynamic_cast<BspLeaf *>(node));
2515	}
2516	}
2517	}
2518	else
2519	{
2520	BspInterior interior = dynamic_cast<BspInterior >(node);
2521
2522	const int cf = Polygon3::ClassifyPlane(nodeGeom.GetPolys(),
2523	interior->GetPlane(),
2524	mEpsilon);
2525
2526	BspNode *front = interior->GetFront();
2527	BspNode *back = interior->GetBack();
2528
2529	BspNodeGeometry *fGeom = new BspNodeGeometry();
2530	BspNodeGeometry *bGeom = new BspNodeGeometry();
2531
2532	geom->SplitGeometry(*fGeom,
2533	*bGeom,
2534	interior->GetPlane(),
2535	mBox,
2536	//0.0000001f);
2537	mEpsilon);
2538
2539	if (cf == Polygon3::BACK_SIDE)
2540	{
2541	nodeStack.push(bspNodePair(interior->GetBack(), bGeom));
2542	DEL_PTR(fGeom);
2543	}
2544	else
2545	{
2546	if (cf == Polygon3::FRONT_SIDE)
2547	{
2548	nodeStack.push(bspNodePair(interior->GetFront(), fGeom));
2549	DEL_PTR(bGeom);
2550	}
2551	else
2552	{ // random decision
2553	nodeStack.push(bspNodePair(front, fGeom));
2554	nodeStack.push(bspNodePair(back, bGeom));
2555	}
2556	}
2557	}
2558
2559	DEL_PTR(geom);
2560	}
2561
2562	return (int)neighbors.size();
2563	}
2564
2565
2566	BspLeaf *BspTree::GetRandomLeaf(const bool onlyUnmailed)
2567	{
2568	stack<BspNode *> nodeStack;
2569
2570	nodeStack.push(mRoot);
2571
2572	int mask = rand();
2573
2574	while (!nodeStack.empty())
2575	{
2576	BspNode *node = nodeStack.top();
2577	nodeStack.pop();
2578
2579	if (node->IsLeaf())
2580	{
2581	if ( (!onlyUnmailed \|\| !node->Mailed()) )
2582	return dynamic_cast<BspLeaf *>(node);
2583	}
2584	else
2585	{
2586	BspInterior interior = dynamic_cast<BspInterior >(node);
2587
2588	// random decision
2589	if (mask & 1)
2590	nodeStack.push(interior->GetBack());
2591	else
2592	nodeStack.push(interior->GetFront());
2593
2594	mask = mask >> 1;
2595	}
2596	}
2597
2598	return NULL;
2599	}
2600
2601
2602	void BspTree::AddToPvs(BspLeaf *leaf,
2603	const BoundedRayContainer &rays,
2604	int &sampleContributions,
2605	int &contributingSamples)
2606	{
2607	sampleContributions = 0;
2608	contributingSamples = 0;
2609
2610	BoundedRayContainer::const_iterator it, it_end = rays.end();
2611
2612	ViewCellLeaf *vc = leaf->GetViewCell();
2613
2614	// add contributions from samples to the PVS
2615	for (it = rays.begin(); it != it_end; ++ it)
2616	{
2617	int contribution = 0;
2618	Ray ray = (it)->mRay;
2619	float relContribution;
2620	if (!ray->intersections.empty())
2621	contribution += vc->GetPvs().AddSample(ray->intersections[0].mObject,
2622	1.0f,
2623	relContribution);
2624
2625	if (ray->sourceObject.mObject)
2626	contribution += vc->GetPvs().AddSample(ray->sourceObject.mObject,
2627	1.0f,
2628	relContribution);
2629
2630	if (contribution)
2631	{
2632	sampleContributions += contribution;
2633	++ contributingSamples;
2634	}
2635
2636	//if (ray->mFlags & Ray::STORE_BSP_INTERSECTIONS)
2637	// ray->bspIntersections.push_back(Ray::BspIntersection((*it)->mMinT, this));
2638	}
2639	}
2640
2641
2642	int BspTree::ComputePvsSize(const BoundedRayContainer &rays) const
2643	{
2644	int pvsSize = 0;
2645
2646	BoundedRayContainer::const_iterator rit, rit_end = rays.end();
2647
2648	Intersectable::NewMail();
2649
2650	for (rit = rays.begin(); rit != rays.end(); ++ rit)
2651	{
2652	Ray ray = (rit)->mRay;
2653
2654	if (!ray->intersections.empty())
2655	{
2656	if (!ray->intersections[0].mObject->Mailed())
2657	{
2658	ray->intersections[0].mObject->Mail();
2659	++ pvsSize;
2660	}
2661	}
2662	if (ray->sourceObject.mObject)
2663	{
2664	if (!ray->sourceObject.mObject->Mailed())
2665	{
2666	ray->sourceObject.mObject->Mail();
2667	++ pvsSize;
2668	}
2669	}
2670	}
2671
2672	return pvsSize;
2673	}
2674
2675
2676	float BspTree::GetEpsilon() const
2677	{
2678	return mEpsilon;
2679	}
2680
2681
2682	int BspTree::CollectMergeCandidates(const vector<BspLeaf *> leaves,
2683	vector<MergeCandidate> &candidates)
2684	{
2685	BspLeaf::NewMail();
2686
2687	vector<BspLeaf *>::const_iterator it, it_end = leaves.end();
2688
2689	int numCandidates = 0;
2690
2691	// find merge candidates and push them into queue
2692	for (it = leaves.begin(); it != it_end; ++ it)
2693	{
2694	BspLeaf leaf = it;
2695
2696	// the same leaves must not be part of two merge candidates
2697	leaf->Mail();
2698	vector<BspLeaf *> neighbors;
2699	FindNeighbors(leaf, neighbors, true);
2700
2701	vector<BspLeaf *>::const_iterator nit, nit_end = neighbors.end();
2702
2703	// TODO: test if at least one ray goes from one leaf to the other
2704	for (nit = neighbors.begin(); nit != nit_end; ++ nit)
2705	{
2706	if ((*nit)->GetViewCell() != leaf->GetViewCell())
2707	{
2708	MergeCandidate mc(leaf->GetViewCell(), (*nit)->GetViewCell());
2709	candidates.push_back(mc);
2710
2711	++ numCandidates;
2712	if ((numCandidates % 1000) == 0)
2713	{
2714	cout << "collected " << numCandidates << " merge candidates" << endl;
2715	}
2716	}
2717	}
2718	}
2719
2720	Debug << "merge queue: " << (int)candidates.size() << endl;
2721	Debug << "leaves in queue: " << numCandidates << endl;
2722
2723
2724	return (int)leaves.size();
2725	}
2726
2727
2728	int BspTree::CollectMergeCandidates(const VssRayContainer &rays,
2729	vector<MergeCandidate> &candidates)
2730	{
2731	ViewCell::NewMail();
2732	long startTime = GetTime();
2733
2734	map<BspLeaf , vector<BspLeaf> > neighborMap;
2735	ViewCellContainer::const_iterator iit;
2736
2737	int numLeaves = 0;
2738
2739	BspLeaf::NewMail();
2740
2741	for (int i = 0; i < (int)rays.size(); ++ i)
2742	{
2743	VssRay *ray = rays[i];
2744
2745	// traverse leaves stored in the rays and compare and
2746	// merge consecutive leaves (i.e., the neighbors in the tree)
2747	if (ray->mViewCells.size() < 2)
2748	continue;
2749
2750	iit = ray->mViewCells.begin();
2751	BspViewCell bspVc = dynamic_cast<BspViewCell >(*(iit ++));
2752	BspLeaf *leaf = bspVc->mLeaf;
2753
2754	// traverse intersections
2755	// consecutive leaves are neighbors => add them to queue
2756	for (; iit != ray->mViewCells.end(); ++ iit)
2757	{
2758	// next pair
2759	BspLeaf *prevLeaf = leaf;
2760	bspVc = dynamic_cast<BspViewCell >(iit);
2761	leaf = bspVc->mLeaf;
2762
2763	// view space not valid or same view cell
2764	if (!leaf->TreeValid() \|\| !prevLeaf->TreeValid() \|\|
2765	(leaf->GetViewCell() == prevLeaf->GetViewCell()))
2766	continue;
2767
2768	vector<BspLeaf *> &neighbors = neighborMap[leaf];
2769
2770	bool found = false;
2771
2772	// both leaves inserted in queue already =>
2773	// look if double pair already exists
2774	if (leaf->Mailed() && prevLeaf->Mailed())
2775	{
2776	vector<BspLeaf *>::const_iterator it, it_end = neighbors.end();
2777
2778	for (it = neighbors.begin(); !found && (it != it_end); ++ it)
2779	if (*it == prevLeaf)
2780	found = true; // already in queue
2781	}
2782
2783	if (!found)
2784	{
2785	// this pair is not in map yet
2786	// => insert into the neighbor map and the queue
2787	neighbors.push_back(prevLeaf);
2788	neighborMap[prevLeaf].push_back(leaf);
2789
2790	leaf->Mail();
2791	prevLeaf->Mail();
2792
2793	MergeCandidate mc(leaf->GetViewCell(), prevLeaf->GetViewCell());
2794
2795	candidates.push_back(mc);
2796
2797	if (((int)candidates.size() % 1000) == 0)
2798	{
2799	cout << "collected " << (int)candidates.size() << " merge candidates" << endl;
2800	}
2801	}
2802	}
2803	}
2804
2805	Debug << "neighbormap size: " << (int)neighborMap.size() << endl;
2806	Debug << "merge queue: " << (int)candidates.size() << endl;
2807	Debug << "leaves in queue: " << numLeaves << endl;
2808
2809
2810	//-- collect the leaves which haven't been found by ray casting
2811	#if 0
2812	cout << "finding additional merge candidates using geometry" << endl;
2813	vector<BspLeaf *> leaves;
2814	CollectLeaves(leaves, true);
2815	Debug << "found " << (int)leaves.size() << " new leaves" << endl << endl;
2816	CollectMergeCandidates(leaves, candidates);
2817	#endif
2818
2819	return numLeaves;
2820	}
2821
2822
2823
2824
2825	/***************************************************************/
2826	/* BspNodeGeometry Implementation */
2827	/***************************************************************/
2828
2829
2830	BspNodeGeometry::BspNodeGeometry(const BspNodeGeometry &rhs)
2831	{
2832	mPolys.reserve(rhs.mPolys.size());
2833	mPlanes.reserve(rhs.mPolys.size());
2834
2835	PolygonContainer::const_iterator it, it_end = rhs.mPolys.end();
2836
2837	int i = 0;
2838
2839	for (it = rhs.mPolys.begin(); it != it_end; ++ it, ++i)
2840	{
2841	Polygon3 poly = it;
2842	Add(new Polygon3(*poly), rhs.mPlanes[i]);
2843	}
2844	}
2845
2846
2847	BspNodeGeometry& BspNodeGeometry::operator=(const BspNodeGeometry& g)
2848	{
2849	if (this == &g)
2850	return *this;
2851
2852	CLEAR_CONTAINER(mPolys);
2853
2854	mPolys.reserve(g.mPolys.size());
2855	mPlanes.reserve(g.mPolys.size());
2856
2857	PolygonContainer::const_iterator it, it_end = g.mPolys.end();
2858
2859	int i = 0;
2860
2861	for (it = g.mPolys.begin(); it != it_end; ++ it, ++ i)
2862	{
2863	Polygon3 poly = it;
2864	Add(new Polygon3(*poly), g.mPlanes[i]);
2865	}
2866
2867	return *this;
2868	}
2869
2870
2871	BspNodeGeometry::BspNodeGeometry(const PolygonContainer &polys)
2872	{
2873	mPolys = polys;
2874	mPlanes.reserve(polys.size());
2875
2876	PolygonContainer::const_iterator it, it_end = polys.end();
2877
2878	for (it = polys.begin(); it != it_end; ++ it)
2879	{
2880	Polygon3 poly = it;
2881	mPlanes.push_back(poly->GetSupportingPlane());
2882	}
2883	}
2884
2885
2886	BspNodeGeometry::~BspNodeGeometry()
2887	{
2888	CLEAR_CONTAINER(mPolys);
2889	}
2890
2891
2892	int BspNodeGeometry::Size() const
2893	{
2894	return (int)mPolys.size();
2895	}
2896
2897
2898	const PolygonContainer &BspNodeGeometry::GetPolys()
2899	{
2900	return mPolys;
2901	}
2902
2903
2904	void BspNodeGeometry::Add(Polygon3 *p, const Plane3 &plane)
2905	{
2906	mPolys.push_back(p);
2907	mPlanes.push_back(plane);
2908	}
2909
2910
2911	float BspNodeGeometry::GetArea() const
2912	{
2913	return Polygon3::GetArea(mPolys);
2914	}
2915
2916
2917	float BspNodeGeometry::GetVolume() const
2918	{
2919	//-- compute volume using tetrahedralization of the geometry
2920	// and adding the volume of the single tetrahedrons
2921	float volume = 0;
2922	const float f = 1.0f / 6.0f;
2923
2924	PolygonContainer::const_iterator pit, pit_end = mPolys.end();
2925
2926	// note: can take arbitrary point, e.g., the origin. However,
2927	// we rather take the center of mass to prevents precision errors
2928	const Vector3 center = CenterOfMass();
2929
2930	for (pit = mPolys.begin(); pit != pit_end; ++ pit)
2931	{
2932	Polygon3 poly = pit;
2933	const Vector3 v0 = poly->mVertices[0] - center;
2934
2935	for (int i = 1; i < (int)poly->mVertices.size() - 1; ++ i)
2936	{
2937	const Vector3 v1 = poly->mVertices[i] - center;
2938	const Vector3 v2 = poly->mVertices[i + 1] - center;
2939
2940	// more robust version using abs and the center of mass
2941	volume += fabs (f * (DotProd(v0, CrossProd(v1, v2))));
2942	}
2943	}
2944
2945	return volume;
2946	}
2947
2948
2949	void BspNodeGeometry::GetBoundingBox(AxisAlignedBox3 &box) const
2950	{
2951	box.Initialize();
2952	box.Include(mPolys);
2953	}
2954
2955
2956	int BspNodeGeometry::Side(const Plane3 &plane, const float eps) const
2957	{
2958	PolygonContainer::const_iterator it, it_end = mPolys.end();
2959
2960	bool onFrontSide = false;
2961	bool onBackSide = false;
2962
2963	for (it = mPolys.begin(); it != it_end; ++ it)
2964	{
2965	const int side = (*it)->Side(plane, eps);
2966
2967	if (side == -1)
2968	onBackSide = true;
2969	else if (side == 1)
2970	onFrontSide = true;
2971
2972	if ((side == 0) \|\| (onBackSide && onFrontSide))
2973	return 0;
2974	}
2975
2976	if (onFrontSide)
2977	return 1;
2978
2979	return -1;
2980	}
2981
2982
2983	int BspNodeGeometry::ComputeIntersection(const AxisAlignedBox3 &box) const
2984	{
2985	// 1: box does not intersect geometry
2986	// 0: box intersects geometry
2987	// -1: box contains geometry
2988
2989	AxisAlignedBox3 boundingBox;
2990	GetBoundingBox(boundingBox);
2991
2992	// no intersections with bounding box
2993	if (!Overlap(box, boundingBox))
2994	{
2995	return 1;
2996	}
2997
2998	// box cotains bounding box of geometry >=> contains geometry
2999	if (box.Includes(boundingBox))
3000	return -1;
3001
3002	int result = 0;
3003
3004	// test geometry planes for intersections
3005	vector<Plane3>::const_iterator it, it_end = mPlanes.end();
3006
3007	for (it = mPlanes.begin(); it != it_end; ++ it)
3008	{
3009	const int side = box.Side(*it);
3010
3011	// box does not intersects geometry
3012	if (side == 1)
3013	{
3014	return 1;
3015	}
3016	//if (side == 0) result = 0;
3017	}
3018
3019	return result;
3020	}
3021
3022
3023	Vector3 BspNodeGeometry::CenterOfMass() const
3024	{
3025	int n = 0;
3026
3027	Vector3 center(0,0,0);
3028
3029	PolygonContainer::const_iterator pit, pit_end = mPolys.end();
3030
3031	for (pit = mPolys.begin(); pit != pit_end; ++ pit)
3032	{
3033	Polygon3 poly = pit;
3034
3035	VertexContainer::const_iterator vit, vit_end = poly->mVertices.end();
3036
3037	for(vit = poly->mVertices.begin(); vit != vit_end; ++ vit)
3038	{
3039	center += *vit;
3040	++ n;
3041	}
3042	}
3043
3044	//Debug << "center: " << center << " new " << center / (float)n << endl;
3045
3046	return center / (float)n;
3047	}
3048
3049
3050	bool BspNodeGeometry::Valid() const
3051	{
3052	if (mPolys.size() < 4)
3053	return false;
3054
3055	return true;
3056	}
3057
3058	void IncludeNodeGeomInMesh(const BspNodeGeometry &geom, Mesh &mesh)
3059	{
3060	// add single polygons to mesh
3061	PolygonContainer::const_iterator it, it_end = geom.mPolys.end();
3062
3063	for (it = geom.mPolys.begin(); it != geom.mPolys.end(); ++ it)
3064	{
3065	Polygon3 poly = (it);
3066	IncludePolyInMesh(*poly, mesh);
3067	}
3068	}
3069
3070
3071	bool BspNodeGeometry::SplitGeometry(BspNodeGeometry &front,
3072	BspNodeGeometry &back,
3073	const Plane3 &splitPlane,
3074	const AxisAlignedBox3 &box,
3075	const float epsilon) const
3076	{
3077	//-- trivial cases
3078	if (0)
3079	{
3080	const int cf = Side(splitPlane, epsilon);
3081
3082	if (cf == -1)
3083	{
3084	back = *this;
3085	return false;
3086	}
3087	else if (cf == 1)
3088	{
3089	front = *this;
3090	return false;
3091	}
3092	}
3093
3094	// get cross section of new polygon
3095	Polygon3 *planePoly = box.CrossSection(splitPlane);
3096
3097	// split polygon with all other polygons
3098	planePoly = SplitPolygon(planePoly, epsilon);
3099
3100	bool splitsGeom = (planePoly != NULL);
3101
3102	//-- new polygon splits all other polygons
3103	for (int i = 0; i < (int)mPolys.size()/* && planePoly*/; ++ i)
3104	{
3105	/// don't use epsilon here to get exact split planes
3106	const int cf =
3107	mPolys[i]->ClassifyPlane(splitPlane, epsilon);
3108
3109	switch (cf)
3110	{
3111	case Polygon3::SPLIT:
3112	{
3113	Polygon3 *poly = new Polygon3(mPolys[i]->mVertices);
3114
3115	Polygon3 *frontPoly = new Polygon3();
3116	Polygon3 *backPoly = new Polygon3();
3117
3118	poly->Split(splitPlane,
3119	*frontPoly,
3120	*backPoly,
3121	epsilon);
3122
3123	DEL_PTR(poly);
3124
3125	if (frontPoly->Valid(epsilon))
3126	{
3127	front.Add(frontPoly, mPlanes[i]);
3128	}
3129	else
3130	{
3131	//Debug << "no f! " << endl;
3132	DEL_PTR(frontPoly);
3133	}
3134
3135	if (backPoly->Valid(epsilon))
3136	{
3137	back.Add(backPoly, mPlanes[i]);
3138	}
3139	else
3140	{
3141	//Debug << "no b! " << endl;
3142	DEL_PTR(backPoly);
3143	}
3144	}
3145
3146	break;
3147	case Polygon3::BACK_SIDE:
3148	back.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3149	break;
3150	case Polygon3::FRONT_SIDE:
3151	front.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3152	break;
3153	// only put into back container (split should have no effect ...)
3154	case Polygon3::COINCIDENT:
3155	//Debug << "error should not come here" << endl;
3156	splitsGeom = false;
3157
3158	if (DotProd(mPlanes[i].mNormal, splitPlane.mNormal > 0))
3159	back.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3160	else
3161	front.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3162	break;
3163	default:
3164	break;
3165	}
3166	}
3167
3168	//-- finally add the new polygon to the child node geometries
3169	if (planePoly)
3170	{
3171	// add polygon with reverse orientation to front cell
3172	Plane3 reversePlane(splitPlane);
3173	reversePlane.ReverseOrientation();
3174
3175	// add polygon with normal pointing into positive half space to back cell
3176	back.Add(planePoly, splitPlane);
3177	//back.mPolys.push_back(planePoly);
3178
3179	Polygon3 *reversePoly = planePoly->CreateReversePolygon();
3180	front.Add(reversePoly, reversePlane);
3181	//Debug << "poly normal : " << reversePoly->GetSupportingPlane().mNormal << " split plane normal " << reversePlane.mNormal << endl;
3182	}
3183
3184
3185	return splitsGeom;
3186	}
3187
3188
3189	Polygon3 BspNodeGeometry::SplitPolygon(Polygon3 planePoly,
3190	const float epsilon) const
3191	{
3192	if (!planePoly->Valid(epsilon))
3193	{
3194	//Debug << "not valid!!" << endl;
3195	DEL_PTR(planePoly);
3196	}
3197	// polygon is split by all other planes
3198	for (int i = 0; (i < (int)mPolys.size()) && planePoly; ++ i)
3199	{
3200	//Plane3 plane = mPolys[i]->GetSupportingPlane();
3201	Plane3 plane = mPlanes[i];
3202
3203	/// don't use epsilon here to get exact split planes
3204	const int cf =
3205	planePoly->ClassifyPlane(plane, epsilon);
3206
3207	// split new polygon with all previous planes
3208	switch (cf)
3209	{
3210	case Polygon3::SPLIT:
3211	{
3212	Polygon3 *frontPoly = new Polygon3();
3213	Polygon3 *backPoly = new Polygon3();
3214
3215	planePoly->Split(plane,
3216	*frontPoly,
3217	*backPoly,
3218	epsilon);
3219
3220	// don't need anymore
3221	DEL_PTR(planePoly);
3222	DEL_PTR(frontPoly);
3223
3224	// back polygon is belonging to geometry
3225	if (backPoly->Valid(epsilon))
3226	planePoly = backPoly;
3227	else
3228	DEL_PTR(backPoly);
3229	}
3230	break;
3231	case Polygon3::FRONT_SIDE:
3232	DEL_PTR(planePoly);
3233	break;
3234	// polygon is taken as it is
3235	case Polygon3::BACK_SIDE:
3236	case Polygon3::COINCIDENT:
3237	default:
3238	break;
3239	}
3240	}
3241
3242	return planePoly;
3243	}
3244
3245
3246	ViewCell *BspTree::GetViewCell(const Vector3 &point)
3247	{
3248	if (mRoot == NULL)
3249	return NULL;
3250
3251
3252	stack<BspNode *> nodeStack;
3253	nodeStack.push(mRoot);
3254
3255	ViewCellLeaf *viewcell = NULL;
3256
3257	while (!nodeStack.empty()) {
3258	BspNode *node = nodeStack.top();
3259	nodeStack.pop();
3260
3261	if (node->IsLeaf()) {
3262	viewcell = dynamic_cast<BspLeaf *>(node)->mViewCell;
3263	break;
3264	} else {
3265
3266	BspInterior interior = dynamic_cast<BspInterior >(node);
3267
3268	// random decision
3269	if (interior->GetPlane().Side(point) < 0)
3270	nodeStack.push(interior->GetBack());
3271	else
3272	nodeStack.push(interior->GetFront());
3273	}
3274	}
3275
3276	return viewcell;
3277	}
3278
3279
3280	bool BspTree::Export(ofstream &stream)
3281	{
3282	ExportNode(mRoot, stream);
3283
3284	return true;
3285	}
3286
3287
3288	void BspTree::ExportNode(BspNode *node, ofstream &stream)
3289	{
3290	if (node->IsLeaf())
3291	{
3292	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3293
3294	int id = -1;
3295	if (leaf->GetViewCell() != mOutOfBoundsCell)
3296	id = leaf->GetViewCell()->GetId();
3297
3298	stream << "<Leaf viewCellId=\"" << id << "\" />" << endl;
3299	}
3300	else
3301	{
3302	BspInterior interior = dynamic_cast<BspInterior >(node);
3303
3304	Plane3 plane = interior->GetPlane();
3305	stream << "<Interior plane=\"" << plane.mNormal.x << " "
3306	<< plane.mNormal.y << " " << plane.mNormal.z << " "
3307	<< plane.mD << "\">" << endl;
3308
3309	ExportNode(interior->GetBack(), stream);
3310	ExportNode(interior->GetFront(), stream);
3311
3312	stream << "</Interior>" << endl;
3313	}
3314	}
3315
3316	}

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