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source: GTP/trunk/Lib/Vis/Preprocessing/src/ViewCellBsp.cpp @ 1789

Revision 1789, 83.1 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	mUsePredefinedViewCells(false),
171	mTimeStamp(1),
172	mViewCellsTree(NULL),
173	mOutOfBoundsCellPartOfTree(false),
174	mOutOfBoundsCell(NULL)
175	{
176	Randomize(); // initialise random generator for heuristics
177	mOutOfBoundsCell = GetOrCreateOutOfBoundsCell();
178
179	/////////
180	//-- termination criteria for autopartition
181
182	Environment::GetSingleton()->GetIntValue("BspTree.Termination.maxDepth", mTermMaxDepth);
183	Environment::GetSingleton()->GetIntValue("BspTree.Termination.minPvs", mTermMinPvs);
184	Environment::GetSingleton()->GetIntValue("BspTree.Termination.minPolygons", mTermMinPolys);
185	Environment::GetSingleton()->GetIntValue("BspTree.Termination.minRays", mTermMinRays);
186	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.minProbability", mTermMinProbability);
187	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.maxRayContribution", mTermMaxRayContribution);
188	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.minAccRayLenght", mTermMinAccRayLength);
189
190
191	/////////
192	//-- factors for bsp tree split plane heuristics
193
194	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.verticalSplits", mVerticalSplitsFactor);
195	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.largestPolyArea", mLargestPolyAreaFactor);
196	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.blockedRays", mBlockedRaysFactor);
197	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.leastRaySplits", mLeastRaySplitsFactor);
198	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.balancedRays", mBalancedRaysFactor);
199	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.pvs", mPvsFactor);
200	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.leastSplits" , mLeastSplitsFactor);
201	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.balancedPolys", mBalancedPolysFactor);
202	Environment::GetSingleton()->GetFloatValue("BspTree.Factor.balancedViewCells", mBalancedViewCellsFactor);
203	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.ct_div_ci", mCtDivCi);
204
205
206	///////////
207	//-- termination criteria for axis aligned split
208
209	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.AxisAligned.ct_div_ci", mAxisAlignedCtDivCi);
210	Environment::GetSingleton()->GetFloatValue("BspTree.Termination.maxCostRatio", mMaxCostRatio);
211	Environment::GetSingleton()->GetIntValue("BspTree.Termination.AxisAligned.minPolys",
212	mTermMinPolysForAxisAligned);
213	Environment::GetSingleton()->GetIntValue("BspTree.Termination.AxisAligned.minRays",
214	mTermMinRaysForAxisAligned);
215	Environment::GetSingleton()->GetIntValue("BspTree.Termination.AxisAligned.minObjects",
216	mTermMinObjectsForAxisAligned);
217
218
219	//////////////
220	//-- partition criteria
221
222	Environment::GetSingleton()->GetIntValue("BspTree.maxPolyCandidates", mMaxPolyCandidates);
223	Environment::GetSingleton()->GetIntValue("BspTree.maxRayCandidates", mMaxRayCandidates);
224	Environment::GetSingleton()->GetIntValue("BspTree.splitPlaneStrategy", mSplitPlaneStrategy);
225	Environment::GetSingleton()->GetFloatValue("BspTree.AxisAligned.splitBorder", mSplitBorder);
226	Environment::GetSingleton()->GetIntValue("BspTree.maxTests", mMaxTests);
227	Environment::GetSingleton()->GetIntValue("BspTree.Termination.maxViewCells", mMaxViewCells);
228
229	Environment::GetSingleton()->GetFloatValue("BspTree.Construction.epsilon", mEpsilon);
230
231	char subdivisionStatsLog[100];
232	Environment::GetSingleton()->GetStringValue("BspTree.subdivisionStats", subdivisionStatsLog);
233	mSubdivisionStats.open(subdivisionStatsLog);
234
235	/////////////////////7
236
237	Debug << "BSP options: " << endl;
238	Debug << "BSP max depth: " << mTermMaxDepth << endl;
239	Debug << "BSP min PVS: " << mTermMinPvs << endl;
240	Debug << "BSP min probability: " << mTermMinProbability << endl;
241	Debug << "BSP max polys: " << mTermMinPolys << endl;
242	Debug << "BSP max rays: " << mTermMinRays << endl;
243	Debug << "BSP max polygon candidates: " << mMaxPolyCandidates << endl;
244	Debug << "BSP max plane candidates: " << mMaxRayCandidates << endl;
245
246	Debug << "Split plane strategy: ";
247	if (mSplitPlaneStrategy & RANDOM_POLYGON)
248	Debug << "random polygon ";
249	if (mSplitPlaneStrategy & AXIS_ALIGNED)
250	Debug << "axis aligned ";
251	if (mSplitPlaneStrategy & LEAST_SPLITS)
252	Debug << "least splits ";
253	if (mSplitPlaneStrategy & BALANCED_POLYS)
254	Debug << "balanced polygons ";
255	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
256	Debug << "balanced view cells ";
257	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
258	Debug << "largest polygon area ";
259	if (mSplitPlaneStrategy & VERTICAL_AXIS)
260	Debug << "vertical axis ";
261	if (mSplitPlaneStrategy & BLOCKED_RAYS)
262	Debug << "blocked rays ";
263	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
264	Debug << "least ray splits ";
265	if (mSplitPlaneStrategy & BALANCED_RAYS)
266	Debug << "balanced rays ";
267	if (mSplitPlaneStrategy & PVS)
268	Debug << "pvs";
269
270	Debug << endl;
271	}
272
273
274	bool BspTree::IsOutOfBounds(ViewCell *vc) const
275	{
276	return vc->GetId() == OUT_OF_BOUNDS_ID;
277	}
278
279
280	const BspTreeStatistics &BspTree::GetStatistics() const
281	{
282	return mStat;
283	}
284
285
286	BspViewCell *BspTree::GetOrCreateOutOfBoundsCell()
287	{
288	if (!mOutOfBoundsCell)
289	{
290	mOutOfBoundsCell = new BspViewCell();
291	mOutOfBoundsCell->SetId(OUT_OF_BOUNDS_ID);
292	mOutOfBoundsCell->SetValid(false);
293	}
294
295	return mOutOfBoundsCell;
296	}
297
298	int BspTree::SplitPolygons(const Plane3 &plane,
299	PolygonContainer &polys,
300	PolygonContainer &frontPolys,
301	PolygonContainer &backPolys,
302	PolygonContainer &coincident) const
303	{
304	int splits = 0;
305
306	#ifdef _Debug
307	Debug << "splitting polygons of node " << this << " with plane " << mPlane << endl;
308	#endif
309
310	PolygonContainer::const_iterator it, it_end = polys.end();
311
312	for (it = polys.begin(); it != polys.end(); ++ it)
313	{
314	Polygon3 poly = it;
315
316	//-- classify polygon
317	const int cf = poly->ClassifyPlane(plane, mEpsilon);
318
319	switch (cf)
320	{
321	case Polygon3::COINCIDENT:
322	coincident.push_back(poly);
323	break;
324	case Polygon3::FRONT_SIDE:
325	frontPolys.push_back(poly);
326	break;
327	case Polygon3::BACK_SIDE:
328	backPolys.push_back(poly);
329	break;
330	case Polygon3::SPLIT:
331	{
332	Polygon3 *front_piece = new Polygon3(poly->mParent);
333	Polygon3 *back_piece = new Polygon3(poly->mParent);
334
335	//-- split polygon into front and back part
336	poly->Split(plane,
337	*front_piece,
338	*back_piece,
339	mEpsilon);
340
341	++ splits; // increase number of splits
342
343	//-- inherit rays from parent polygon for blocked ray criterium
344	poly->InheritRays(front_piece, back_piece);
345
346	// check if polygons still valid
347	if (front_piece->Valid(mEpsilon))
348	frontPolys.push_back(front_piece);
349	else
350	DEL_PTR(front_piece);
351
352	if (back_piece->Valid(mEpsilon))
353	backPolys.push_back(back_piece);
354	else
355	DEL_PTR(back_piece);
356
357	#ifdef GTP_DEBUG
358	Debug << "split " << poly << endl << front_piece << endl << *back_piece << endl;
359	#endif
360	DEL_PTR(poly);
361	}
362	break;
363	default:
364	Debug << "SHOULD NEVER COME HERE\n";
365	break;
366	}
367	}
368
369	return splits;
370	}
371
372
373	void BspTreeStatistics::Print(ostream &app) const
374	{
375	app << "===== BspTree statistics ===============\n";
376
377	app << setprecision(4);
378
379	app << "#N_CTIME ( Construction time [s] )\n" << Time() << " \n";
380
381	app << "#N_NODES ( Number of nodes )\n" << nodes << "\n";
382
383	app << "#N_INTERIORS ( Number of interior nodes )\n" << Interior() << "\n";
384
385	app << "#N_LEAVES ( Number of leaves )\n" << Leaves() << "\n";
386
387	app << "#N_POLYSPLITS ( Number of polygon splits )\n" << polySplits << "\n";
388
389	app << "#AXIS_ALIGNED_SPLITS (number of axis aligned splits)\n" << splits[0] + splits[1] + splits[2] << endl;
390
391	app << "#N_SPLITS ( Number of splits in axes x y z)\n";
392
393	for (int i = 0; i < 3; ++ i)
394	app << splits[i] << " ";
395	app << endl;
396
397	app << "#N_PMAXDEPTHLEAVES ( Percentage of leaves at maximum depth )\n"
398	<< maxDepthNodes * 100 / (double)Leaves() << endl;
399
400	app << "#N_PMINPVSLEAVES ( Percentage of leaves with mininimal PVS )\n"
401	<< minPvsNodes * 100 / (double)Leaves() << endl;
402
403	app << "#N_PMINRAYSLEAVES ( Percentage of leaves with minimal number of rays)\n"
404	<< minRaysNodes * 100 / (double)Leaves() << endl;
405
406	app << "#N_MAXCOSTNODES ( Percentage of leaves with terminated because of max cost ratio )\n"
407	<< maxCostNodes * 100 / (double)Leaves() << endl;
408
409	app << "#N_PMINPROBABILITYLEAVES ( Percentage of leaves with mininum probability )\n"
410	<< minProbabilityNodes * 100 / (double)Leaves() << endl;
411
412	app << "#N_PMAXRAYCONTRIBLEAVES ( Percentage of leaves with maximal ray contribution )\n"
413	<< maxRayContribNodes * 100 / (double)Leaves() << endl;
414
415	app << "#N_PMAXDEPTH ( Maximal reached depth )\n" << maxDepth << endl;
416
417	app << "#N_PMINDEPTH ( Minimal reached depth )\n" << minDepth << endl;
418
419	app << "#AVGDEPTH ( average depth )\n" << AvgDepth() << endl;
420
421	app << "#N_INPUTPOLYGONS (number of input polygons )\n" << polys << endl;
422
423	app << "#N_INVALIDLEAVES (number of invalid leaves )\n" << invalidLeaves << endl;
424
425	app << "#N_RAYS (number of rays / leaf)\n" << AvgRays() << endl;
426	//app << "#N_PVS: " << pvs << endl;
427
428	app << "#N_ROUTPUT_INPUT_POLYGONS ( ratio polygons after subdivision / input polygons )\n" <<
429	(polys + polySplits) / (double)polys << endl;
430
431	app << "===== END OF BspTree statistics ==========\n";
432	}
433
434
435	BspTree::~BspTree()
436	{
437	DEL_PTR(mRoot);
438
439	if (mOutOfBoundsCellPartOfTree)
440	{
441	// out of bounds cell not part of tree =>
442	// delete manually
443	DEL_PTR(mOutOfBoundsCell);
444	}
445	}
446
447
448	BspNode *BspTree::GetRoot() const
449	{
450	return mRoot;
451	}
452
453
454	void BspTree::SetViewCellsTree(ViewCellsTree *viewCellsTree)
455	{
456	mViewCellsTree = viewCellsTree;
457	}
458
459
460	void BspTree::InsertViewCell(ViewCellLeaf *viewCell)
461	{
462	// don't generate new view cell, insert this view cell
463	mUsePredefinedViewCells = true;
464	PolygonContainer *polys = new PolygonContainer();
465
466	// extract polygons that guide the split process
467	mStat.polys += AddMeshToPolygons(viewCell->GetMesh(), *polys, viewCell);
468	mBbox.Include(viewCell->GetBox()); // add to BSP aabb
469
470	InsertPolygons(polys);
471	}
472
473
474	void BspTree::InsertPolygons(PolygonContainer *polys)
475	{
476	BspTraversalStack tStack;
477
478	// traverse existing tree or create new tree
479	if (!mRoot)
480	mRoot = new BspLeaf();
481
482	tStack.push(BspTraversalData(mRoot,
483	polys,
484	0,
485	mOutOfBoundsCell,
486	new BoundedRayContainer(),
487	0,
488	mUseAreaForPvs ? mBbox.SurfaceArea() : mBbox.GetVolume(),
489	new BspNodeGeometry()));
490
491	while (!tStack.empty())
492	{
493	// filter polygons donw the tree
494	BspTraversalData tData = tStack.top();
495	tStack.pop();
496
497	if (!tData.mNode->IsLeaf())
498	{
499	BspInterior interior = dynamic_cast<BspInterior >(tData.mNode);
500
501	///////////////////
502	//-- filter view cell polygons down the tree until a leaf is reached
503	if (!tData.mPolygons->empty())
504	{
505	PolygonContainer *frontPolys = new PolygonContainer();
506	PolygonContainer *backPolys = new PolygonContainer();
507	PolygonContainer coincident;
508
509	int splits = 0;
510
511	// split viewcell polygons with respect to split plane
512	splits += SplitPolygons(interior->GetPlane(),
513	*tData.mPolygons,
514	*frontPolys,
515	*backPolys,
516	coincident);
517
518	// extract view cells associated with the split polygons
519	ViewCellLeaf *frontViewCell = mOutOfBoundsCell;
520	ViewCellLeaf *backViewCell = mOutOfBoundsCell;
521
522	BspTraversalData frontData(interior->GetFront(),
523	frontPolys,
524	tData.mDepth + 1,
525	mOutOfBoundsCell,
526	tData.mRays,
527	tData.mPvs,
528	mUseAreaForPvs ? mBbox.SurfaceArea() : mBbox.GetVolume(),
529	new BspNodeGeometry());
530
531	BspTraversalData backData(interior->GetBack(),
532	backPolys,
533	tData.mDepth + 1,
534	mOutOfBoundsCell,
535	tData.mRays,
536	tData.mPvs,
537	mUseAreaForPvs ? mBbox.SurfaceArea() : mBbox.GetVolume(),
538	new BspNodeGeometry());
539
540	if (mUsePredefinedViewCells)
541	{
542	ExtractViewCells(frontData,
543	backData,
544	coincident,
545	interior->mPlane);
546	}
547
548	// don't need coincident polygons anymore
549	CLEAR_CONTAINER(coincident);
550
551	mStat.polySplits += splits;
552
553	// push the children on the stack
554	tStack.push(frontData);
555	tStack.push(backData);
556	}
557
558	// cleanup
559	DEL_PTR(tData.mPolygons);
560	DEL_PTR(tData.mRays);
561	}
562	else
563	{
564	// reached leaf => subdivide current viewcell
565	BspNode *subRoot = Subdivide(tStack, tData);
566	}
567	}
568	}
569
570
571	int BspTree::AddMeshToPolygons(Mesh *mesh,
572	PolygonContainer &polys,
573	MeshInstance *parent)
574	{
575	FaceContainer::const_iterator fi, fi_end = mesh->mFaces.end();
576
577	// copy the face data to polygons
578	for (fi = mesh->mFaces.begin(); fi != fi_end; ++ fi)
579	{
580	Polygon3 poly = new Polygon3((fi), mesh);
581
582	if (poly->Valid(mEpsilon))
583	{
584	poly->mParent = parent; // set parent intersectable
585	polys.push_back(poly);
586	}
587	else
588	{
589	DEL_PTR(poly);
590	}
591	}
592	return (int)mesh->mFaces.size();
593	}
594
595
596	int BspTree::AddToPolygonSoup(const ViewCellContainer &viewCells,
597	PolygonContainer &polys,
598	int maxObjects)
599	{
600	int limit = (maxObjects > 0) ?
601	Min((int)viewCells.size(), maxObjects) : (int)viewCells.size();
602
603	int polysSize = 0;
604
605	for (int i = 0; i < limit; ++ i)
606	{
607	Mesh *mesh = viewCells[i]->GetMesh();
608
609	if (mesh)
610	{
611	// copy the mesh into polygons and add to BSP tree aabb
612	mBbox.Include(viewCells[i]->GetBox());
613	polysSize += AddMeshToPolygons(mesh, polys, viewCells[i]);
614	}
615	}
616
617	return polysSize;
618	}
619
620
621	int BspTree::AddToPolygonSoup(const ObjectContainer &objects,
622	PolygonContainer &polys,
623	int maxObjects,
624	bool addToBbox)
625	{
626	int limit = (maxObjects > 0) ?
627	Min((int)objects.size(), maxObjects) : (int)objects.size();
628
629	for (int i = 0; i < limit; ++i)
630	{
631	Intersectable *object = objects[i];
632	Mesh *mesh = NULL;
633
634	switch (object->Type()) // extract the meshes
635	{
636	case Intersectable::MESH_INSTANCE:
637	mesh = dynamic_cast<MeshInstance *>(object)->GetMesh();
638	break;
639	case Intersectable::VIEW_CELL:
640	mesh = dynamic_cast<ViewCell *>(object)->GetMesh();
641	break;
642	case Intersectable::TRANSFORMED_MESH_INSTANCE:
643	{
644	TransformedMeshInstance mi = dynamic_cast<TransformedMeshInstance >(object);
645
646	if (!mi->GetMesh())
647	break;
648	mesh = new Mesh();
649	mi->GetTransformedMesh(*mesh);
650	break;
651	}
652	default:
653	Debug << "intersectable type not supported" << endl;
654	break;
655	}
656
657	if (!mesh) continue;
658
659	// copy the mesh data to polygons
660	if (addToBbox)
661	{
662	mBbox.Include(object->GetBox()); // add to BSP tree aabb
663	}
664
665	AddMeshToPolygons(mesh, polys, mOutOfBoundsCell);
666
667	// cleanup
668	if (object->Type() == Intersectable::TRANSFORMED_MESH_INSTANCE)
669	{
670	DEL_PTR(mesh);
671	}
672	}
673
674	return (int)polys.size();
675	}
676
677
678	void BspTree::Construct(const ViewCellContainer &viewCells)
679	{
680	// construct hierarchy over the given view cells
681	mUsePredefinedViewCells = true;
682
683	mStat.nodes = 1;
684	mBbox.Initialize(); // initialise bsp tree bounding box
685
686	// copy view cell meshes into one big polygon soup
687	PolygonContainer *polys = new PolygonContainer();
688	mStat.polys = AddToPolygonSoup(viewCells, *polys);
689
690	Exporter *expo = Exporter::GetExporter("dummy2.wrl");
691	expo->ExportPolygons(*polys);
692	delete expo;
693	// construct tree from the view cell polygons
694	Construct(polys, new BoundedRayContainer());
695	}
696
697
698	void BspTree::Construct(const ObjectContainer &objects)
699	{
700	// generate new view cells for this type
701	mUsePredefinedViewCells = false;
702
703	mStat.nodes = 1;
704	mBbox.Initialize(); // initialise bsp tree bounding box
705
706	PolygonContainer *polys = new PolygonContainer();
707
708	// copy mesh instance polygons into one big polygon soup
709	mStat.polys = AddToPolygonSoup(objects, *polys);
710
711	// construct tree from polygon soup
712	Construct(polys, new BoundedRayContainer());
713	}
714
715
716	void BspTree::PreprocessPolygons(PolygonContainer &polys)
717	{
718	// preprocess: throw out polygons coincident to the view space box (not needed)
719	PolygonContainer boxPolys;
720	mBbox.ExtractPolys(boxPolys);
721	vector<Plane3> boxPlanes;
722
723	PolygonContainer::iterator pit, pit_end = boxPolys.end();
724
725	// extract planes of box
726	// TODO: can be done more elegantly than here
727	// where we first extract polygons, then compute their planes
728	for (pit = boxPolys.begin(); pit != pit_end; ++ pit)
729	{
730	boxPlanes.push_back((*pit)->GetSupportingPlane());
731	}
732
733	pit_end = polys.end();
734
735	for (pit = polys.begin(); pit != pit_end; ++ pit)
736	{
737	vector<Plane3>::const_iterator bit, bit_end = boxPlanes.end();
738
739	for (bit = boxPlanes.begin(); (bit != bit_end) && (*pit); ++ bit)
740	{
741	const int cf = (pit)->ClassifyPlane(bit, mEpsilon);
742
743	if (cf == Polygon3::COINCIDENT)
744	{
745	DEL_PTR(*pit);
746	//Debug << "coincident!!" << endl;
747	}
748	}
749	}
750
751	// remove deleted entries
752	for (int i = 0; i < (int)polys.size(); ++ i)
753	{
754	while (!polys[i] && (i < (int)polys.size()))
755	{
756	swap(polys[i], polys.back());
757	polys.pop_back();
758	}
759	}
760
761	CLEAR_CONTAINER(boxPolys);
762	}
763
764
765	void BspTree::Construct(const RayContainer &sampleRays,
766	AxisAlignedBox3 *forcedBoundingBox)
767	{
768	// generate new view cells for this contruction type
769	mUsePredefinedViewCells = false;
770
771	mStat.nodes = 1;
772
773	if (forcedBoundingBox)
774	{
775	mBbox = *forcedBoundingBox;
776	}
777	else
778	{
779	mBbox.Initialize(); // initialise BSP tree bounding box
780	}
781
782	PolygonContainer *polys = new PolygonContainer();
783	BoundedRayContainer *rays = new BoundedRayContainer();
784
785	RayContainer::const_iterator rit, rit_end = sampleRays.end();
786
787	long startTime = GetTime();
788	Debug << "** Extracting polygons from rays **\n";
789
790	std::map<Face , Polygon3 > facePolyMap;
791
792	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
793	{
794	//////////////
795	//-- extract polygons intersected by the rays
796	Ray ray = rit;
797
798	// get ray-face intersection. Store polygon representing the rays together
799	// with rays intersecting the face.
800	if (!ray->intersections.empty())
801	{
802	MeshInstance obj = dynamic_cast<MeshInstance >(ray->intersections[0].mObject);
803
804	Mesh *mesh;
805	if (obj->Type() == Intersectable::TRANSFORMED_MESH_INSTANCE)
806	{
807	TransformedMeshInstance *tmobj =
808	dynamic_cast<TransformedMeshInstance *>(obj);
809
810	mesh = new Mesh();
811	tmobj->GetTransformedMesh(*mesh);
812	}
813	else // MeshInstance
814	{
815	mesh = obj->GetMesh();
816	}
817
818	Face *face = mesh->mFaces[ray->intersections[0].mFace];
819	std::map<Face , Polygon3 >::iterator it = facePolyMap.find(face);
820
821	if (it != facePolyMap.end())
822	{
823	//store rays if needed for heuristics
824	if (mSplitPlaneStrategy & BLOCKED_RAYS)
825	(*it).second->mPiercingRays.push_back(ray);
826	}
827	else
828	{
829	//store rays if needed for heuristics
830	Polygon3 *poly = new Polygon3(face, mesh);
831	poly->mParent = obj;
832	polys->push_back(poly);
833
834	if (mSplitPlaneStrategy & BLOCKED_RAYS)
835	poly->mPiercingRays.push_back(ray);
836
837	facePolyMap[face] = poly;
838	}
839
840	// cleanup
841	if (obj->Type() == Intersectable::TRANSFORMED_MESH_INSTANCE)
842	DEL_PTR(mesh);
843	}
844	}
845	// clear helper structure
846	// note: memory will not be released using clear!
847	facePolyMap.clear();
848
849	// compute bounding box
850	if (!forcedBoundingBox)
851	{
852	mBbox.Include(*polys);
853	}
854
855	////////////
856	//-- store rays
857	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
858	{
859	Ray ray = rit;
860	ray->SetId(-1); // reset id
861
862	float minT, maxT;
863	if (mBbox.GetRaySegment(*ray, minT, maxT))
864	rays->push_back(new BoundedRay(ray, minT, maxT));
865	}
866
867	// throw out bad polygons
868	PreprocessPolygons(*polys);
869
870	mStat.polys = (int)polys->size();
871
872	Debug << "** Finished polygon extraction **" << endl;
873	Debug << (int)polys->size() << " polys extracted from " << (int)sampleRays.size() << " rays" << endl;
874	Debug << "extraction time: " << TimeDiff(startTime, GetTime())*1e-3 << "s" << endl;
875
876	Construct(polys, rays);
877	}
878
879
880	void BspTree::Construct(const ObjectContainer &objects,
881	const RayContainer &sampleRays,
882	AxisAlignedBox3 *forcedBoundingBox)
883	{
884	// generate new view cells for this construction type
885	mUsePredefinedViewCells = false;
886
887	mStat.nodes = 1;
888	mBbox.Initialize(); // initialise BSP tree bounding box
889
890	if (forcedBoundingBox)
891	{
892	mBbox = *forcedBoundingBox;
893	}
894
895	BoundedRayContainer *rays = new BoundedRayContainer();
896	PolygonContainer *polys = new PolygonContainer();
897
898	// copy mesh instance polygons into one big polygon soup
899	mStat.polys = AddToPolygonSoup(objects, *polys, 0, !forcedBoundingBox);
900
901	///////
902	//-- store rays
903	RayContainer::const_iterator rit, rit_end = sampleRays.end();
904
905	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
906	{
907	Ray ray = rit;
908	ray->SetId(-1); // reset id
909
910	float minT, maxT;
911	if (mBbox.GetRaySegment(*ray, minT, maxT))
912	rays->push_back(new BoundedRay(ray, minT, maxT));
913	}
914
915	PreprocessPolygons(*polys);
916	Debug << "tree has " << (int)polys->size() << " polys, " << (int)sampleRays.size() << " rays" << endl;
917	Construct(polys, rays);
918	}
919
920
921	void BspTree::Construct(PolygonContainer polys, BoundedRayContainer rays)
922	{
923	BspTraversalStack tStack;
924	mRoot = new BspLeaf();
925
926	// constrruct root node geometry
927	BspNodeGeometry *geom = new BspNodeGeometry();
928	ConstructGeometry(mRoot, *geom);
929
930	BspTraversalData tData(mRoot,
931	polys,
932	0,
933	mOutOfBoundsCell,
934	rays,
935	ComputePvsSize(*rays),
936	mUseAreaForPvs ? geom->GetArea() : geom->GetVolume(),
937	geom);
938
939	mTotalCost = tData.mPvs * tData.mProbability / mBbox.GetVolume();
940	mTotalPvsSize = tData.mPvs;
941
942	mSubdivisionStats
943	<< "#ViewCells\n1\n" << endl
944	<< "#RenderCostDecrease\n0\n" << endl
945	<< "#TotalRenderCost\n" << mTotalCost << endl
946	<< "#AvgRenderCost\n" << mTotalPvsSize << endl;
947
948	tStack.push(tData);
949
950	// used for intermediate time measurements and progress
951	long interTime = GetTime();
952	int nleaves = 500;
953
954	mStat.Start();
955	cout << "Constructing bsp tree ...\n";
956	long startTime = GetTime();
957	while (!tStack.empty())
958	{
959	tData = tStack.top();
960	tStack.pop();
961
962	// subdivide leaf node
963	BspNode *r = Subdivide(tStack, tData);
964
965	if (r == mRoot)
966	Debug << "BSP tree construction time spent at root: "
967	<< TimeDiff(startTime, GetTime())*1e-3 << " secs" << endl;
968
969	if (mStat.Leaves() >= nleaves)
970	{
971	nleaves += 500;
972
973	cout << "leaves=" << mStat.Leaves() << endl;
974	Debug << "needed "
975	<< TimeDiff(interTime, GetTime())*1e-3
976	<< " secs to create 500 leaves" << endl;
977	interTime = GetTime();
978	}
979	}
980
981	cout << "finished\n";
982
983	mStat.Stop();
984	}
985
986
987	bool BspTree::TerminationCriteriaMet(const BspTraversalData &data) const
988	{
989	return
990	(((int)data.mPolygons->size() <= mTermMinPolys) \|\|
991	((int)data.mRays->size() <= mTermMinRays) \|\|
992	(data.mPvs <= mTermMinPvs) \|\|
993	(data.mProbability <= mTermMinProbability) \|\|
994	(data.mDepth >= mTermMaxDepth) \|\|
995	(mStat.Leaves() >= mMaxViewCells) \|\|
996	(data.GetAvgRayContribution() > mTermMaxRayContribution));
997	}
998
999
1000	BspNode *BspTree::Subdivide(BspTraversalStack &tStack, BspTraversalData &tData)
1001	{
1002	////////
1003	//-- terminate traversal
1004
1005	if (TerminationCriteriaMet(tData))
1006	{
1007	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
1008
1009	BspViewCell *viewCell;
1010
1011	if (!mUsePredefinedViewCells)
1012	{ // generate new view cell for each leaf
1013	viewCell = new BspViewCell();cout << "g";
1014	}
1015	else
1016	{
1017	// add predefined view cell to leaf
1018	viewCell = dynamic_cast<BspViewCell *>(tData.mViewCell);
1019
1020	// out of bounds cell can be handled as any other view cell,
1021	// responsibility for deleting it has the view cells manager.
1022	if (IsOutOfBounds(viewCell))
1023	{
1024	mOutOfBoundsCellPartOfTree = true;
1025	}
1026
1027	}
1028
1029	leaf->SetViewCell(viewCell);
1030	viewCell->mLeaves.push_back(leaf);
1031
1032	//float probability = max(0.0f, tData.mProbability);
1033	float probability = tData.mProbability;
1034
1035	if (mUseAreaForPvs)
1036	viewCell->SetArea(probability);
1037	else
1038	viewCell->SetVolume(probability);
1039
1040	///////////
1041	//-- add pvs contribution of rays
1042
1043	if (viewCell != mOutOfBoundsCell)
1044	{
1045	int conSamp = 0, sampCon = 0;
1046	AddToPvs(leaf, *tData.mRays, conSamp, sampCon);
1047
1048	mStat.contributingSamples += conSamp;
1049	mStat.sampleContributions += sampCon;
1050	}
1051
1052	if (1) EvaluateLeafStats(tData);
1053
1054	////////
1055	//-- clean up
1056
1057	// discard polygons
1058	CLEAR_CONTAINER(*tData.mPolygons);
1059	// discard rays
1060	CLEAR_CONTAINER(*tData.mRays);
1061
1062	delete tData.mPolygons;
1063	delete tData.mRays;
1064	delete tData.mGeometry;
1065
1066	return leaf;
1067	}
1068
1069	///////////
1070	//-- continue subdivision
1071
1072	PolygonContainer coincident;
1073
1074	BspTraversalData tFrontData(NULL, new PolygonContainer(), tData.mDepth + 1, mOutOfBoundsCell,
1075	new BoundedRayContainer(), 0, 0, new BspNodeGeometry());
1076	BspTraversalData tBackData(NULL, new PolygonContainer(), tData.mDepth + 1, mOutOfBoundsCell,
1077	new BoundedRayContainer(), 0, 0, new BspNodeGeometry());
1078
1079
1080	// create new interior node and two leaf nodes
1081	BspInterior *interior =
1082	SubdivideNode(tData, tFrontData, tBackData, coincident);
1083
1084	if (1)
1085	{
1086	int pvsData = tData.mPvs;
1087
1088	float cData = (float)pvsData * tData.mProbability;
1089	float cFront = (float)tFrontData.mPvs * tFrontData.mProbability;
1090	float cBack = (float)tBackData.mPvs * tBackData.mProbability;
1091
1092	float costDecr = (cFront + cBack - cData) / mBbox.GetVolume();
1093
1094	mTotalCost += costDecr;
1095	mTotalPvsSize += tFrontData.mPvs + tBackData.mPvs - pvsData;
1096
1097	mSubdivisionStats
1098	<< "#ViewCells\n" << mStat.Leaves() << endl
1099	<< "#RenderCostDecrease\n" << -costDecr << endl
1100	<< "#TotalRenderCost\n" << mTotalCost << endl
1101	<< "#AvgRenderCost\n" << mTotalPvsSize / mStat.Leaves() << endl;
1102	}
1103
1104	// extract view cells from coincident polygons
1105	// with respect to the orientation of their normal
1106	// note: if front or back polygons are empty,
1107	// we get the valid in - out classification for the view cell
1108
1109	if (mUsePredefinedViewCells)
1110	{
1111	ExtractViewCells(tFrontData,
1112	tBackData,
1113	coincident,
1114	interior->mPlane);
1115	}
1116
1117	// don't need coincident polygons anymory
1118	CLEAR_CONTAINER(coincident);
1119
1120	// push the children on the stack
1121	tStack.push(tFrontData);
1122	tStack.push(tBackData);
1123
1124	////////
1125	//-- cleanup
1126
1127	DEL_PTR(tData.mNode);
1128	DEL_PTR(tData.mPolygons);
1129	DEL_PTR(tData.mRays);
1130	DEL_PTR(tData.mGeometry);
1131
1132	return interior;
1133	}
1134
1135
1136	void BspTree::ExtractViewCells(BspTraversalData &frontData,
1137	BspTraversalData &backData,
1138	const PolygonContainer &coincident,
1139	const Plane3 &splitPlane) const
1140	{
1141	// if not empty, tree is further subdivided => don't have to find view cell
1142	bool foundFront = !frontData.mPolygons->empty();
1143	bool foundBack = !frontData.mPolygons->empty();
1144
1145	PolygonContainer::const_iterator it =
1146	coincident.begin(), it_end = coincident.end();
1147
1148	//////////
1149	//-- find first view cells in front and back leafs
1150
1151	for (; !(foundFront && foundBack) && (it != it_end); ++ it)
1152	{
1153	if (DotProd((*it)->GetNormal(), splitPlane.mNormal) > 0)
1154	{
1155	backData.mViewCell = dynamic_cast<ViewCellLeaf >((it)->mParent);
1156	foundBack = true;
1157	}
1158	else
1159	{
1160	frontData.mViewCell = dynamic_cast<ViewCellLeaf >((it)->mParent);
1161	foundFront = true;
1162	}
1163	}
1164	}
1165
1166
1167	BspInterior *BspTree::SubdivideNode(BspTraversalData &tData,
1168	BspTraversalData &frontData,
1169	BspTraversalData &backData,
1170	PolygonContainer &coincident)
1171	{
1172	mStat.nodes += 2;
1173
1174	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
1175
1176	// select subdivision plane
1177	BspInterior *interior = new BspInterior(SelectPlane(leaf, tData));
1178
1179	#ifdef GTP_DEBUG
1180	Debug << interior << endl;
1181	#endif
1182
1183	// subdivide rays into front and back rays
1184	SplitRays(interior->mPlane, tData.mRays, frontData.mRays, *backData.mRays);
1185
1186	// subdivide polygons with plane
1187	mStat.polySplits += SplitPolygons(interior->GetPlane(),
1188	*tData.mPolygons,
1189	*frontData.mPolygons,
1190	*backData.mPolygons,
1191	coincident);
1192
1193
1194	// compute pvs
1195	frontData.mPvs = ComputePvsSize(*frontData.mRays);
1196	backData.mPvs = ComputePvsSize(*backData.mRays);
1197
1198	// split geometry and compute area
1199	if (1)
1200	{
1201	tData.mGeometry->SplitGeometry(*frontData.mGeometry,
1202	*backData.mGeometry,
1203	interior->mPlane,
1204	mBbox,
1205	//0.000000000001);
1206	mEpsilon);
1207
1208
1209	if (mUseAreaForPvs)
1210	{
1211	frontData.mProbability = frontData.mGeometry->GetArea();
1212	backData.mProbability = backData.mGeometry->GetArea();
1213	}
1214	else
1215	{
1216	frontData.mProbability = frontData.mGeometry->GetVolume();
1217	backData.mProbability = tData.mProbability - frontData.mProbability;
1218	}
1219	}
1220
1221	//-- create front and back leaf
1222
1223	BspInterior *parent = leaf->GetParent();
1224
1225	// replace a link from node's parent
1226	if (!leaf->IsRoot())
1227	{
1228	parent->ReplaceChildLink(leaf, interior);
1229	interior->SetParent(parent);
1230	}
1231	else // new root
1232	{
1233	mRoot = interior;
1234	}
1235
1236	// and setup child links
1237	interior->SetupChildLinks(new BspLeaf(interior), new BspLeaf(interior));
1238
1239	frontData.mNode = interior->GetFront();
1240	backData.mNode = interior->GetBack();
1241
1242	interior->mTimeStamp = mTimeStamp ++;
1243
1244	//DEL_PTR(leaf);
1245	return interior;
1246	}
1247
1248
1249	void BspTree::SortSubdivisionCandidates(const PolygonContainer &polys,
1250	const int axis,
1251	vector<SortableEntry> &splitCandidates) const
1252	{
1253	splitCandidates.clear();
1254
1255	int requestedSize = 2 * (int)polys.size();
1256	// creates a sorted split candidates array
1257	splitCandidates.reserve(requestedSize);
1258
1259	PolygonContainer::const_iterator it, it_end = polys.end();
1260
1261	AxisAlignedBox3 box;
1262
1263	// insert all queries
1264	for(it = polys.begin(); it != it_end; ++ it)
1265	{
1266	box.Initialize();
1267	box.Include((it));
1268
1269	splitCandidates.push_back(SortableEntry(SortableEntry::POLY_MIN, box.Min(axis), *it));
1270	splitCandidates.push_back(SortableEntry(SortableEntry::POLY_MAX, box.Max(axis), *it));
1271	}
1272
1273	stable_sort(splitCandidates.begin(), splitCandidates.end());
1274	}
1275
1276
1277	float BspTree::BestCostRatio(const PolygonContainer &polys,
1278	const AxisAlignedBox3 &box,
1279	const int axis,
1280	float &position,
1281	int &objectsBack,
1282	int &objectsFront) const
1283	{
1284	vector<SortableEntry> splitCandidates;
1285
1286	SortSubdivisionCandidates(polys, axis, splitCandidates);
1287
1288	// go through the lists, count the number of objects left and right
1289	// and evaluate the following cost funcion:
1290	// C = ct_div_ci + (ol + or)/queries
1291
1292	int objectsLeft = 0, objectsRight = (int)polys.size();
1293
1294	float minBox = box.Min(axis);
1295	float maxBox = box.Max(axis);
1296	float boxArea = box.SurfaceArea();
1297
1298	float minBand = minBox + mSplitBorder * (maxBox - minBox);
1299	float maxBand = minBox + (1.0f - mSplitBorder) * (maxBox - minBox);
1300
1301	float minSum = 1e20f;
1302	vector<SortableEntry>::const_iterator ci, ci_end = splitCandidates.end();
1303
1304	for(ci = splitCandidates.begin(); ci != ci_end; ++ ci)
1305	{
1306	switch ((*ci).type)
1307	{
1308	case SortableEntry::POLY_MIN:
1309	++ objectsLeft;
1310	break;
1311	case SortableEntry::POLY_MAX:
1312	-- objectsRight;
1313	break;
1314	default:
1315	break;
1316	}
1317
1318	if ((ci).value > minBand && (ci).value < maxBand)
1319	{
1320	AxisAlignedBox3 lbox = box;
1321	AxisAlignedBox3 rbox = box;
1322	lbox.SetMax(axis, (*ci).value);
1323	rbox.SetMin(axis, (*ci).value);
1324
1325	const float sum = objectsLeft * lbox.SurfaceArea() +
1326	objectsRight * rbox.SurfaceArea();
1327
1328	if (sum < minSum)
1329	{
1330	minSum = sum;
1331	position = (*ci).value;
1332
1333	objectsBack = objectsLeft;
1334	objectsFront = objectsRight;
1335	}
1336	}
1337	}
1338
1339	const float oldCost = (float)polys.size();
1340	const float newCost = mAxisAlignedCtDivCi + minSum / boxArea;
1341	const float ratio = newCost / oldCost;
1342
1343	#ifdef GTP_DEBUG
1344	Debug << "====================" << endl;
1345	Debug << "costRatio=" << ratio << " pos=" << position<<" t=" << (position - minBox)/(maxBox - minBox)
1346	<< "\t o=(" << objectsBack << "," << objectsFront << ")" << endl;
1347	#endif
1348	return ratio;
1349	}
1350
1351	bool BspTree::SelectAxisAlignedPlane(Plane3 &plane,
1352	const PolygonContainer &polys) const
1353	{
1354	AxisAlignedBox3 box;
1355	box.Initialize();
1356
1357	// create bounding box of region
1358	box.Include(polys);
1359
1360	int objectsBack = 0, objectsFront = 0;
1361	int axis = 0;
1362	float costRatio = MAX_FLOAT;
1363	Vector3 position;
1364
1365	//-- area subdivision
1366	for (int i = 0; i < 3; ++ i)
1367	{
1368	float p = 0;
1369	float r = BestCostRatio(polys, box, i, p, objectsBack, objectsFront);
1370
1371	if (r < costRatio)
1372	{
1373	costRatio = r;
1374	axis = i;
1375	position = p;
1376	}
1377	}
1378
1379	if (costRatio >= mMaxCostRatio)
1380	return false;
1381
1382	Vector3 norm(0,0,0); norm[axis] = 1.0f;
1383	plane = Plane3(norm, position);
1384
1385	return true;
1386	}
1387
1388
1389	Plane3 BspTree::SelectPlane(BspLeaf *leaf, BspTraversalData &data)
1390	{
1391	if ((!mMaxPolyCandidates \|\| data.mPolygons->empty()) &&
1392	(!mMaxRayCandidates \|\| data.mRays->empty()))
1393	{
1394	Debug << "Warning: No autopartition polygon candidate available\n";
1395
1396	// return axis aligned split
1397	AxisAlignedBox3 box;
1398	box.Initialize();
1399
1400	// create bounding box of region
1401	box.Include(*data.mPolygons);
1402
1403	const int axis = box.Size().DrivingAxis();
1404	const Vector3 position = (box.Min()[axis] + box.Max()[axis]) * 0.5f;
1405
1406	Vector3 norm(0,0,0); norm[axis] = 1.0f;
1407	return Plane3(norm, position);
1408	}
1409
1410	if ((mSplitPlaneStrategy & AXIS_ALIGNED) &&
1411	((int)data.mPolygons->size() > mTermMinPolysForAxisAligned) &&
1412	((int)data.mRays->size() > mTermMinRaysForAxisAligned) &&
1413	((mTermMinObjectsForAxisAligned < 0) \|\|
1414	(Polygon3::ParentObjectsSize(*data.mPolygons) > mTermMinObjectsForAxisAligned)))
1415	{
1416	Plane3 plane;
1417	if (SelectAxisAlignedPlane(plane, *data.mPolygons))
1418	return plane;
1419	}
1420
1421	// simplest strategy: just take next polygon
1422	if (mSplitPlaneStrategy & RANDOM_POLYGON)
1423	{
1424	if (!data.mPolygons->empty())
1425	{
1426	Polygon3 *nextPoly =
1427	(*data.mPolygons)[(int)RandomValue(0, (Real)((int)data.mPolygons->size() - 1))];
1428	return nextPoly->GetSupportingPlane();
1429	}
1430	else
1431	{
1432	const int candidateIdx = (int)RandomValue(0, (Real)((int)data.mRays->size() - 1));
1433	BoundedRay bRay = (data.mRays)[candidateIdx];
1434
1435	Ray *ray = bRay->mRay;
1436
1437	const Vector3 minPt = ray->Extrap(bRay->mMinT);
1438	const Vector3 maxPt = ray->Extrap(bRay->mMaxT);
1439
1440	const Vector3 pt = (maxPt + minPt) * 0.5;
1441
1442	const Vector3 normal = ray->GetDir();
1443
1444	return Plane3(normal, pt);
1445	}
1446
1447	return Plane3();
1448	}
1449
1450	// use heuristics to find appropriate plane
1451	return SelectPlaneHeuristics(leaf, data);
1452	}
1453
1454
1455	Plane3 BspTree::ChooseCandidatePlane(const BoundedRayContainer &rays) const
1456	{
1457	const int candidateIdx = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1458	BoundedRay *bRay = rays[candidateIdx];
1459	Ray *ray = bRay->mRay;
1460
1461	const Vector3 minPt = ray->Extrap(bRay->mMinT);
1462	const Vector3 maxPt = ray->Extrap(bRay->mMaxT);
1463
1464	const Vector3 pt = (maxPt + minPt) * 0.5;
1465
1466	const Vector3 normal = ray->GetDir();
1467
1468	return Plane3(normal, pt);
1469	}
1470
1471	Plane3 BspTree::ChooseCandidatePlane2(const BoundedRayContainer &rays) const
1472	{
1473	Vector3 pt[3];
1474	int idx[3];
1475	int cmaxT = 0;
1476	int cminT = 0;
1477	bool chooseMin = false;
1478
1479	for (int j = 0; j < 3; j ++)
1480	{
1481	idx[j] = (int)RandomValue(0, Real((int)rays.size() * 2 - 1));
1482
1483	if (idx[j] >= (int)rays.size())
1484	{
1485	idx[j] -= (int)rays.size();
1486	chooseMin = (cminT < 2);
1487	}
1488	else
1489	chooseMin = (cmaxT < 2);
1490
1491	BoundedRay *bRay = rays[idx[j]];
1492	pt[j] = chooseMin ? bRay->mRay->Extrap(bRay->mMinT) :
1493	bRay->mRay->Extrap(bRay->mMaxT);
1494	}
1495
1496	return Plane3(pt[0], pt[1], pt[2]);
1497	}
1498
1499
1500	Plane3 BspTree::ChooseCandidatePlane3(const BoundedRayContainer &rays) const
1501	{
1502	Vector3 pt[3];
1503
1504	int idx1 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1505	int idx2 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1506
1507	// check if rays different
1508	if (idx1 == idx2)
1509	idx2 = (idx2 + 1) % (int)rays.size();
1510
1511	const BoundedRay *ray1 = rays[idx1];
1512	const BoundedRay *ray2 = rays[idx2];
1513
1514	// normal vector of the plane parallel to both lines
1515	const Vector3 norm =
1516	Normalize(CrossProd(ray1->mRay->GetDir(), ray2->mRay->GetDir()));
1517
1518	const Vector3 orig1 = ray1->mRay->Extrap(ray1->mMinT);
1519	const Vector3 orig2 = ray2->mRay->Extrap(ray2->mMinT);
1520
1521	// vector from line 1 to line 2
1522	const Vector3 vd = orig1 - orig2;
1523
1524	// project vector on normal to get distance
1525	const float dist = DotProd(vd, norm);
1526
1527	// point on plane lies halfway between the two planes
1528	const Vector3 planePt = orig1 + norm * dist * 0.5;
1529
1530	return Plane3(norm, planePt);
1531	}
1532
1533
1534	Plane3 BspTree::SelectPlaneHeuristics(BspLeaf *leaf, BspTraversalData &data)
1535	{
1536	float lowestCost = MAX_FLOAT;
1537	Plane3 bestPlane;
1538	// intermediate plane
1539	Plane3 plane;
1540
1541	const int limit = Min((int)data.mPolygons->size(), mMaxPolyCandidates);
1542	int maxIdx = (int)data.mPolygons->size();
1543
1544	for (int i = 0; i < limit; ++ i)
1545	{
1546	// assure that no index is taken twice
1547	const int candidateIdx = (int)RandomValue(0, (Real)(-- maxIdx));
1548
1549	Polygon3 poly = (data.mPolygons)[candidateIdx];
1550
1551	// swap candidate to the end to avoid testing same plane
1552	std::swap((data.mPolygons)[maxIdx], (data.mPolygons)[candidateIdx]);
1553	//Polygon3 poly = (data.mPolygons)[(int)RandomValue(0, (int)polys.size() - 1)];
1554
1555	// evaluate current candidate
1556	const float candidateCost =
1557	SplitPlaneCost(poly->GetSupportingPlane(), data);
1558
1559	if (candidateCost < lowestCost)
1560	{
1561	bestPlane = poly->GetSupportingPlane();
1562	lowestCost = candidateCost;
1563	}
1564	}
1565
1566	//-- choose candidate planes extracted from rays
1567	for (int i = 0; i < mMaxRayCandidates; ++ i)
1568	{
1569	plane = ChooseCandidatePlane3(*data.mRays);
1570	const float candidateCost = SplitPlaneCost(plane, data);
1571
1572	if (candidateCost < lowestCost)
1573	{
1574	bestPlane = plane;
1575	lowestCost = candidateCost;
1576	}
1577	}
1578
1579	#ifdef GTP_DEBUG
1580	Debug << "plane lowest cost: " << lowestCost << endl;
1581	#endif
1582
1583	return bestPlane;
1584	}
1585
1586
1587	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1588	const PolygonContainer &polys) const
1589	{
1590	float val = 0;
1591
1592	float sumBalancedPolys = 0;
1593	float sumSplits = 0;
1594	float sumPolyArea = 0;
1595	float sumBalancedViewCells = 0;
1596	float sumBlockedRays = 0;
1597	float totalBlockedRays = 0;
1598	//float totalArea = 0;
1599	int totalViewCells = 0;
1600
1601	// need three unique ids for each type of view cell
1602	// for balanced view cells criterium
1603	ViewCell::NewMail();
1604	const int backId = ViewCell::sMailId;
1605	ViewCell::NewMail();
1606	const int frontId = ViewCell::sMailId;
1607	ViewCell::NewMail();
1608	const int frontAndBackId = ViewCell::sMailId;
1609
1610	bool useRand;
1611	int limit;
1612
1613	// choose test polyongs randomly if over threshold
1614	if ((int)polys.size() > mMaxTests)
1615	{
1616	useRand = true;
1617	limit = mMaxTests;
1618	}
1619	else
1620	{
1621	useRand = false;
1622	limit = (int)polys.size();
1623	}
1624
1625	for (int i = 0; i < limit; ++ i)
1626	{
1627	const int testIdx = useRand ? (int)RandomValue(0, (Real)(limit - 1)) : i;
1628
1629	Polygon3 *poly = polys[testIdx];
1630
1631	const int classification =
1632	poly->ClassifyPlane(candidatePlane, mEpsilon);
1633
1634	if (mSplitPlaneStrategy & BALANCED_POLYS)
1635	sumBalancedPolys += sBalancedPolysTable[classification];
1636
1637	if (mSplitPlaneStrategy & LEAST_SPLITS)
1638	sumSplits += sLeastPolySplitsTable[classification];
1639
1640	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
1641	{
1642	if (classification == Polygon3::COINCIDENT)
1643	sumPolyArea += poly->GetArea();
1644	//totalArea += area;
1645	}
1646
1647	if (mSplitPlaneStrategy & BLOCKED_RAYS)
1648	{
1649	const float blockedRays = (float)poly->mPiercingRays.size();
1650
1651	if (classification == Polygon3::COINCIDENT)
1652	sumBlockedRays += blockedRays;
1653
1654	totalBlockedRays += blockedRays;
1655	}
1656
1657	// assign view cells to back or front according to classificaion
1658	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
1659	{
1660	MeshInstance *viewCell = poly->mParent;
1661
1662	// assure that we only count a view cell
1663	// once for the front and once for the back side of the plane
1664	if (classification == Polygon3::FRONT_SIDE)
1665	{
1666	if ((viewCell->mMailbox != frontId) &&
1667	(viewCell->mMailbox != frontAndBackId))
1668	{
1669	sumBalancedViewCells += 1.0;
1670
1671	if (viewCell->mMailbox != backId)
1672	viewCell->mMailbox = frontId;
1673	else
1674	viewCell->mMailbox = frontAndBackId;
1675
1676	++ totalViewCells;
1677	}
1678	}
1679	else if (classification == Polygon3::BACK_SIDE)
1680	{
1681	if ((viewCell->mMailbox != backId) &&
1682	(viewCell->mMailbox != frontAndBackId))
1683	{
1684	sumBalancedViewCells -= 1.0;
1685
1686	if (viewCell->mMailbox != frontId)
1687	viewCell->mMailbox = backId;
1688	else
1689	viewCell->mMailbox = frontAndBackId;
1690
1691	++ totalViewCells;
1692	}
1693	}
1694	}
1695	}
1696
1697	const float polysSize = (float)polys.size() + Limits::Small;
1698
1699	// all values should be approx. between 0 and 1 so they can be combined
1700	// and scaled with the factors according to their importance
1701	if (mSplitPlaneStrategy & BALANCED_POLYS)
1702	val += mBalancedPolysFactor * fabs(sumBalancedPolys) / polysSize;
1703
1704	if (mSplitPlaneStrategy & LEAST_SPLITS)
1705	val += mLeastSplitsFactor * sumSplits / polysSize;
1706
1707	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
1708	// HACK: polys.size should be total area so scaling is between 0 and 1
1709	val += mLargestPolyAreaFactor * (float)polys.size() / sumPolyArea;
1710
1711	if (mSplitPlaneStrategy & BLOCKED_RAYS)
1712	if (totalBlockedRays != 0)
1713	val += mBlockedRaysFactor * (totalBlockedRays - sumBlockedRays) / totalBlockedRays;
1714
1715	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
1716	val += mBalancedViewCellsFactor * fabs(sumBalancedViewCells) /
1717	((float)totalViewCells + Limits::Small);
1718
1719	return val;
1720	}
1721
1722
1723	inline void BspTree::GenerateUniqueIdsForPvs()
1724	{
1725	Intersectable::NewMail(); sBackId = Intersectable::sMailId;
1726	Intersectable::NewMail(); sFrontId = Intersectable::sMailId;
1727	Intersectable::NewMail(); sFrontAndBackId = Intersectable::sMailId;
1728	}
1729
1730
1731	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1732	const BoundedRayContainer &rays,
1733	const int pvs,
1734	const float probability,
1735	const BspNodeGeometry &cell) const
1736	{
1737	float val = 0;
1738
1739	float sumBalancedRays = 0;
1740	float sumRaySplits = 0;
1741
1742	int frontPvs = 0;
1743	int backPvs = 0;
1744
1745	// probability that view point lies in child
1746	float pOverall = 0;
1747	float pFront = 0;
1748	float pBack = 0;
1749
1750	const bool pvsUseLen = false;
1751
1752
1753	if (mSplitPlaneStrategy & PVS)
1754	{
1755	// create unique ids for pvs heuristics
1756	GenerateUniqueIdsForPvs();
1757
1758	// construct child geometry with regard to the candidate split plane
1759	BspNodeGeometry geomFront;
1760	BspNodeGeometry geomBack;
1761
1762	const bool splitSuccessFull =
1763	cell.SplitGeometry(geomFront,
1764	geomBack,
1765	candidatePlane,
1766	mBbox,
1767	mEpsilon);
1768
1769	if (mUseAreaForPvs)
1770	{
1771	pFront = geomFront.GetArea();
1772	pBack = geomBack.GetArea();
1773	}
1774	else
1775	{
1776	pFront = geomFront.GetVolume();
1777	pBack = pOverall - pFront;
1778	}
1779
1780
1781	// give penalty to unbalanced split
1782	if (1 &&
1783	(!splitSuccessFull \|\| (pFront <= 0) \|\| (pBack <= 0) \|\|
1784	!geomFront.Valid() \|\| !geomBack.Valid()))
1785	{
1786	//Debug << "error f: " << pFront << " b: " << pBack << endl;
1787	return 99999.9f;
1788	}
1789
1790	pOverall = probability;
1791	}
1792
1793	bool useRand;
1794	int limit;
1795
1796	// choose test polyongs randomly if over threshold
1797	if ((int)rays.size() > mMaxTests)
1798	{
1799	useRand = true;
1800	limit = mMaxTests;
1801	}
1802	else
1803	{
1804	useRand = false;
1805	limit = (int)rays.size();
1806	}
1807
1808	for (int i = 0; i < limit; ++ i)
1809	{
1810	const int testIdx = useRand ? (int)RandomValue(0, (Real)(limit - 1)) : i;
1811
1812	BoundedRay *bRay = rays[testIdx];
1813
1814	Ray *ray = bRay->mRay;
1815	const float minT = bRay->mMinT;
1816	const float maxT = bRay->mMaxT;
1817
1818	Vector3 entP, extP;
1819
1820	const int cf =
1821	ray->ClassifyPlane(candidatePlane, minT, maxT, entP, extP);
1822
1823	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
1824	{
1825	sumBalancedRays += sBalancedRaysTable[cf];
1826	}
1827
1828	if (mSplitPlaneStrategy & BALANCED_RAYS)
1829	{
1830	sumRaySplits += sLeastRaySplitsTable[cf];
1831	}
1832
1833	if (mSplitPlaneStrategy & PVS)
1834	{
1835	// in case the ray intersects an object
1836	// assure that we only count the object
1837	// once for the front and once for the back side of the plane
1838
1839	// add the termination object
1840	if (!ray->intersections.empty())
1841	AddObjToPvs(ray->intersections[0].mObject, cf, frontPvs, backPvs);
1842
1843	// add the source object
1844	AddObjToPvs(ray->sourceObject.mObject, cf, frontPvs, backPvs);
1845	}
1846	}
1847
1848	const float raysSize = (float)rays.size() + Limits::Small;
1849
1850	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
1851	val += mLeastRaySplitsFactor * sumRaySplits / raysSize;
1852
1853	if (mSplitPlaneStrategy & BALANCED_RAYS)
1854	val += mBalancedRaysFactor * fabs(sumBalancedRays) / raysSize;
1855
1856	const float denom = pOverall * (float)pvs + Limits::Small;
1857
1858	if (mSplitPlaneStrategy & PVS)
1859	{
1860	val += mPvsFactor * (frontPvs * pFront + (backPvs * pBack)) / denom;
1861	}
1862
1863
1864	#ifdef GTP_DEBUG
1865	Debug << "totalpvs: " << pvs << " ptotal: " << pOverall
1866	<< " frontpvs: " << frontPvs << " pFront: " << pFront
1867	<< " backpvs: " << backPvs << " pBack: " << pBack << endl << endl;
1868	#endif
1869
1870	return val;
1871	}
1872
1873	void BspTree::AddObjToPvs(Intersectable *obj,
1874	const int cf,
1875	int &frontPvs,
1876	int &backPvs) const
1877	{
1878	if (!obj)
1879	return;
1880	// TODO: does this really belong to no pvs?
1881	//if (cf == Ray::COINCIDENT) return;
1882
1883	// object belongs to both PVS
1884	const bool bothSides = (cf == Ray::FRONT_BACK) \|\|
1885	(cf == Ray::BACK_FRONT) \|\|
1886	(cf == Ray::COINCIDENT);
1887
1888	if ((cf == Ray::FRONT) \|\| bothSides)
1889	{
1890	if ((obj->mMailbox != sFrontId) &&
1891	(obj->mMailbox != sFrontAndBackId))
1892	{
1893	++ frontPvs;
1894
1895	if (obj->mMailbox == sBackId)
1896	obj->mMailbox = sFrontAndBackId;
1897	else
1898	obj->mMailbox = sFrontId;
1899	}
1900	}
1901
1902	if ((cf == Ray::BACK) \|\| bothSides)
1903	{
1904	if ((obj->mMailbox != sBackId) &&
1905	(obj->mMailbox != sFrontAndBackId))
1906	{
1907	++ backPvs;
1908
1909	if (obj->mMailbox == sFrontId)
1910	obj->mMailbox = sFrontAndBackId;
1911	else
1912	obj->mMailbox = sBackId;
1913	}
1914	}
1915	}
1916
1917
1918	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1919	BspTraversalData &data) const
1920	{
1921	float val = 0;
1922
1923	if (mSplitPlaneStrategy & VERTICAL_AXIS)
1924	{
1925	Vector3 tinyAxis(0,0,0); tinyAxis[mBbox.Size().TinyAxis()] = 1.0f;
1926	// we put a penalty on the dot product between the "tiny" vertical axis
1927	// and the split plane axis
1928	val += mVerticalSplitsFactor *
1929	fabs(DotProd(candidatePlane.mNormal, tinyAxis));
1930	}
1931
1932	// the following criteria loop over all polygons to find the cost value
1933	if ((mSplitPlaneStrategy & BALANCED_POLYS) \|\|
1934	(mSplitPlaneStrategy & LEAST_SPLITS) \|\|
1935	(mSplitPlaneStrategy & LARGEST_POLY_AREA) \|\|
1936	(mSplitPlaneStrategy & BALANCED_VIEW_CELLS) \|\|
1937	(mSplitPlaneStrategy & BLOCKED_RAYS))
1938	{
1939	val += SplitPlaneCost(candidatePlane, *data.mPolygons);
1940	}
1941
1942	// the following criteria loop over all rays to find the cost value
1943	if ((mSplitPlaneStrategy & BALANCED_RAYS) \|\|
1944	(mSplitPlaneStrategy & LEAST_RAY_SPLITS) \|\|
1945	(mSplitPlaneStrategy & PVS))
1946	{
1947	val += SplitPlaneCost(candidatePlane, *data.mRays, data.mPvs,
1948	data.mProbability, *data.mGeometry);
1949	}
1950
1951	// return linear combination of the sums
1952	return val;
1953	}
1954
1955	void BspTree::CollectLeaves(vector<BspLeaf *> &leaves) const
1956	{
1957	stack<BspNode *> nodeStack;
1958	nodeStack.push(mRoot);
1959
1960	while (!nodeStack.empty())
1961	{
1962	BspNode *node = nodeStack.top();
1963
1964	nodeStack.pop();
1965
1966	if (node->IsLeaf())
1967	{
1968	BspLeaf leaf = (BspLeaf )node;
1969	leaves.push_back(leaf);
1970	}
1971	else
1972	{
1973	BspInterior interior = dynamic_cast<BspInterior >(node);
1974
1975	nodeStack.push(interior->GetBack());
1976	nodeStack.push(interior->GetFront());
1977	}
1978	}
1979	}
1980
1981
1982	AxisAlignedBox3 BspTree::GetBoundingBox() const
1983	{
1984	return mBbox;
1985	}
1986
1987
1988	void BspTree::EvaluateLeafStats(const BspTraversalData &data)
1989	{
1990	// the node became a leaf -> evaluate stats for leafs
1991	BspLeaf leaf = dynamic_cast<BspLeaf >(data.mNode);
1992
1993	// store maximal and minimal depth
1994	if (data.mDepth > mStat.maxDepth)
1995	mStat.maxDepth = data.mDepth;
1996
1997	if (data.mDepth < mStat.minDepth)
1998	mStat.minDepth = data.mDepth;
1999
2000	// accumulate depth to compute average depth
2001	mStat.accumDepth += data.mDepth;
2002	// accumulate rays to compute rays / leaf
2003	mStat.accumRays += (int)data.mRays->size();
2004
2005	if (data.mDepth >= mTermMaxDepth)
2006	++ mStat.maxDepthNodes;
2007
2008	if (data.mPvs < mTermMinPvs)
2009	++ mStat.minPvsNodes;
2010
2011	if ((int)data.mRays->size() < mTermMinRays)
2012	++ mStat.minRaysNodes;
2013
2014	if (data.GetAvgRayContribution() > mTermMaxRayContribution)
2015	++ mStat.maxRayContribNodes;
2016
2017	if (data.mProbability <= mTermMinProbability)
2018	++ mStat.minProbabilityNodes;
2019
2020	#ifdef GTP_DEBUG
2021	Debug << "BSP stats: "
2022	<< "Depth: " << data.mDepth << " (max: " << mTermMaxDepth << "), "
2023	<< "PVS: " << data.mPvs << " (min: " << mTermMinPvs << "), "
2024	<< "Probability: " << data.mProbability << " (min: " << mTermMinProbability << "), "
2025	<< "#polygons: " << (int)data.mPolygons->size() << " (max: " << mTermMinPolys << "), "
2026	<< "#rays: " << (int)data.mRays->size() << " (max: " << mTermMinRays << "), "
2027	<< "#pvs: " << leaf->GetViewCell()->GetPvs().EvalPvsCost() << "=, "
2028	<< "#avg ray contrib (pvs): " << (float)data.mPvs / (float)data.mRays->size() << endl;
2029	#endif
2030	}
2031
2032
2033	int BspTree::_CastRay(Ray &ray)
2034	{
2035	int hits = 0;
2036
2037	stack<BspRayTraversalData> tStack;
2038
2039	float maxt, mint;
2040
2041	if (!mBbox.GetRaySegment(ray, mint, maxt))
2042	return 0;
2043
2044	ViewCell::NewMail();
2045
2046	Vector3 entp = ray.Extrap(mint);
2047	Vector3 extp = ray.Extrap(maxt);
2048
2049	BspNode *node = mRoot;
2050	BspNode *farChild = NULL;
2051
2052	while (1)
2053	{
2054	if (!node->IsLeaf())
2055	{
2056	BspInterior in = dynamic_cast<BspInterior >(node);
2057
2058	Plane3 splitPlane = in->GetPlane();
2059	const int entSide = splitPlane.Side(entp);
2060	const int extSide = splitPlane.Side(extp);
2061
2062	if (entSide < 0)
2063	{
2064	node = in->GetBack();
2065
2066	if(extSide <= 0) // plane does not split ray => no far child
2067	continue;
2068
2069	farChild = in->GetFront(); // plane splits ray
2070
2071	} else if (entSide > 0)
2072	{
2073	node = in->GetFront();
2074
2075	if (extSide >= 0) // plane does not split ray => no far child
2076	continue;
2077
2078	farChild = in->GetBack(); // plane splits ray
2079	}
2080	else // ray and plane are coincident
2081	{
2082	// WHAT TO DO IN THIS CASE ?
2083	//break;
2084	node = in->GetFront();
2085	continue;
2086	}
2087
2088	// push data for far child
2089	tStack.push(BspRayTraversalData(farChild, extp, maxt));
2090
2091	// find intersection of ray segment with plane
2092	float t;
2093	extp = splitPlane.FindIntersection(ray.GetLoc(), extp, &t);
2094	maxt *= t;
2095
2096	} else // reached leaf => intersection with view cell
2097	{
2098	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2099
2100	if (!leaf->mViewCell->Mailed())
2101	{
2102	//ray.bspIntersections.push_back(Ray::BspIntersection(maxt, leaf));
2103	leaf->mViewCell->Mail();
2104	++ hits;
2105	}
2106
2107	//-- fetch the next far child from the stack
2108	if (tStack.empty())
2109	break;
2110
2111	entp = extp;
2112	mint = maxt; // NOTE: need this?
2113
2114	if (ray.GetType() == Ray::LINE_SEGMENT && mint > 1.0f)
2115	break;
2116
2117	BspRayTraversalData &s = tStack.top();
2118
2119	node = s.mNode;
2120	extp = s.mExitPoint;
2121	maxt = s.mMaxT;
2122
2123	tStack.pop();
2124	}
2125	}
2126
2127	return hits;
2128	}
2129
2130
2131	int BspTree::CastLineSegment(const Vector3 &origin,
2132	const Vector3 &termination,
2133	ViewCellContainer &viewcells)
2134	{
2135	int hits = 0;
2136	stack<BspRayTraversalData> tStack;
2137
2138	float mint = 0.0f, maxt = 1.0f;
2139
2140	//ViewCell::NewMail();
2141
2142	Vector3 entp = origin;
2143	Vector3 extp = termination;
2144
2145	BspNode *node = mRoot;
2146	BspNode *farChild = NULL;
2147
2148
2149	const float thresh = 1 ? 1e-6f : 0.0f;
2150
2151	while (1)
2152	{
2153	if (!node->IsLeaf())
2154	{
2155	BspInterior in = dynamic_cast<BspInterior >(node);
2156
2157	Plane3 splitPlane = in->GetPlane();
2158
2159	const int entSide = splitPlane.Side(entp, thresh);
2160	const int extSide = splitPlane.Side(extp, thresh);
2161
2162	if (entSide < 0)
2163	{
2164	node = in->GetBack();
2165
2166	// plane does not split ray => no far child
2167	if (extSide <= 0)
2168	continue;
2169
2170	farChild = in->GetFront(); // plane splits ray
2171	}
2172	else if (entSide > 0)
2173	{
2174	node = in->GetFront();
2175
2176	if (extSide >= 0) // plane does not split ray => no far child
2177	continue;
2178
2179	farChild = in->GetBack(); // plane splits ray
2180	}
2181	else // one of the ray end points is on the plane
2182	{ // NOTE: what to do if ray is coincident with plane?
2183	if (extSide < 0)
2184	node = in->GetBack();
2185	else //if (extSide > 0)
2186	node = in->GetFront();
2187	//else break; // coincident => count no intersections
2188
2189	continue; // no far child
2190	}
2191
2192	// push data for far child
2193	tStack.push(BspRayTraversalData(farChild, extp, maxt));
2194
2195	// find intersection of ray segment with plane
2196	float t;
2197	extp = splitPlane.FindIntersection(origin, extp, &t);
2198	maxt *= t;
2199	}
2200	else
2201	{
2202	// reached leaf => intersection with view cell
2203	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2204
2205	if (!leaf->mViewCell->Mailed())
2206	{
2207	viewcells.push_back(leaf->mViewCell);
2208	leaf->mViewCell->Mail();
2209	++ hits;
2210	}
2211
2212	//-- fetch the next far child from the stack
2213	if (tStack.empty())
2214	break;
2215
2216	entp = extp;
2217	mint = maxt; // NOTE: need this?
2218
2219	BspRayTraversalData &s = tStack.top();
2220
2221	node = s.mNode;
2222	extp = s.mExitPoint;
2223	maxt = s.mMaxT;
2224
2225	tStack.pop();
2226	}
2227	}
2228
2229	return hits;
2230	}
2231
2232
2233	void BspTree::CollectViewCells(ViewCellContainer &viewCells) const
2234	{
2235	stack<BspNode *> nodeStack;
2236	nodeStack.push(mRoot);
2237
2238	ViewCell::NewMail();
2239
2240	while (!nodeStack.empty())
2241	{
2242	BspNode *node = nodeStack.top();
2243	nodeStack.pop();
2244
2245	if (node->IsLeaf())
2246	{
2247	ViewCellLeaf viewCell = dynamic_cast<BspLeaf >(node)->mViewCell;
2248
2249	if (!viewCell->Mailed())
2250	{
2251	viewCell->Mail();
2252	viewCells.push_back(viewCell);
2253	}
2254	}
2255	else
2256	{
2257	BspInterior interior = dynamic_cast<BspInterior >(node);
2258
2259	nodeStack.push(interior->GetFront());
2260	nodeStack.push(interior->GetBack());
2261	}
2262	}
2263	}
2264
2265
2266	BspTreeStatistics &BspTree::GetStat()
2267	{
2268	return mStat;
2269	}
2270
2271
2272	float BspTree::AccumulatedRayLength(BoundedRayContainer &rays) const
2273	{
2274	float len = 0;
2275
2276	BoundedRayContainer::const_iterator it, it_end = rays.end();
2277
2278	for (it = rays.begin(); it != it_end; ++ it)
2279	{
2280	len += SqrDistance((it)->mRay->Extrap((it)->mMinT),
2281	(it)->mRay->Extrap((it)->mMaxT));
2282	}
2283
2284	return len;
2285	}
2286
2287
2288	int BspTree::SplitRays(const Plane3 &plane,
2289	BoundedRayContainer &rays,
2290	BoundedRayContainer &frontRays,
2291	BoundedRayContainer &backRays)
2292	{
2293	int splits = 0;
2294
2295	while (!rays.empty())
2296	{
2297	BoundedRay *bRay = rays.back();
2298	Ray *ray = bRay->mRay;
2299	float minT = bRay->mMinT;
2300	float maxT = bRay->mMaxT;
2301
2302	rays.pop_back();
2303
2304	Vector3 entP, extP;
2305
2306	const int cf =
2307	ray->ClassifyPlane(plane, minT, maxT, entP, extP);
2308
2309	// set id to ray classification
2310	ray->SetId(cf);
2311
2312	switch (cf)
2313	{
2314	case Ray::COINCIDENT: // TODO: should really discard ray?
2315	frontRays.push_back(bRay);
2316	break;
2317	case Ray::BACK:
2318	backRays.push_back(bRay);
2319	break;
2320	case Ray::FRONT:
2321	frontRays.push_back(bRay);
2322	break;
2323	case Ray::FRONT_BACK:
2324	{
2325	// find intersection of ray segment with plane
2326	const float t = plane.FindT(ray->GetLoc(), extP);
2327
2328	const float newT = t * maxT;
2329
2330	frontRays.push_back(new BoundedRay(ray, minT, newT));
2331	backRays.push_back(new BoundedRay(ray, newT, maxT));
2332
2333	DEL_PTR(bRay);
2334	}
2335	break;
2336	case Ray::BACK_FRONT:
2337	{
2338	// find intersection of ray segment with plane
2339	const float t = plane.FindT(ray->GetLoc(), extP);
2340	const float newT = t * bRay->mMaxT;
2341
2342	backRays.push_back(new BoundedRay(ray, minT, newT));
2343	frontRays.push_back(new BoundedRay(ray, newT, maxT));
2344
2345	DEL_PTR(bRay);
2346
2347	++ splits;
2348	}
2349	break;
2350	default:
2351	Debug << "Should not come here 4" << endl;
2352	break;
2353	}
2354	}
2355
2356	return splits;
2357	}
2358
2359	void BspTree::ExtractHalfSpaces(BspNode *n, vector<Plane3> &halfSpaces) const
2360	{
2361	BspNode *lastNode;
2362
2363	do
2364	{
2365	lastNode = n;
2366
2367	// want to get planes defining geometry of this node => don't take
2368	// split plane of node itself
2369	n = n->GetParent();
2370
2371	if (n)
2372	{
2373	BspInterior interior = dynamic_cast<BspInterior >(n);
2374	Plane3 halfSpace = dynamic_cast<BspInterior *>(interior)->GetPlane();
2375
2376	if (interior->GetBack() != lastNode)
2377	halfSpace.ReverseOrientation();
2378
2379	halfSpaces.push_back(halfSpace);
2380	}
2381	}
2382	while (n);
2383	}
2384
2385
2386	void BspTree::ConstructGeometry(ViewCell *vc,
2387	BspNodeGeometry &vcGeom) const
2388	{
2389	// if false, cannot construct geometry for interior leaf
2390	if (!mViewCellsTree)
2391	return;
2392
2393	ViewCellContainer leaves;
2394	mViewCellsTree->CollectLeaves(vc, leaves);
2395
2396	ViewCellContainer::const_iterator it, it_end = leaves.end();
2397
2398	for (it = leaves.begin(); it != it_end; ++ it)
2399	{
2400	// per definition out of bounds cell has zero volume
2401	if (IsOutOfBounds(*it))
2402	continue;
2403
2404	BspViewCell bspVc = dynamic_cast<BspViewCell >(*it);
2405	vector<BspLeaf *>::const_iterator bit, bit_end = bspVc->mLeaves.end();
2406
2407	for (bit = bspVc->mLeaves.begin(); bit != bit_end; ++ bit)
2408	{
2409	BspLeaf l = bit;
2410	ConstructGeometry(l, vcGeom);
2411	}
2412	}
2413	}
2414
2415
2416	void BspTree::ConstructGeometry(BspNode *n,
2417	BspNodeGeometry &geom) const
2418	{
2419	vector<Plane3> halfSpaces;
2420	ExtractHalfSpaces(n, halfSpaces);
2421
2422	PolygonContainer candidatePolys;
2423	vector<Plane3> candidatePlanes;
2424
2425	vector<Plane3>::const_iterator pit, pit_end = halfSpaces.end();
2426
2427	// bounded planes are added to the polygons
2428	for (pit = halfSpaces.begin(); pit != pit_end; ++ pit)
2429	{
2430	Polygon3 p = GetBoundingBox().CrossSection(pit);
2431
2432	if (p->Valid(mEpsilon))
2433	{
2434	candidatePolys.push_back(p);
2435	candidatePlanes.push_back(*pit);
2436	}
2437	}
2438
2439	// add faces of bounding box (also could be faces of the cell)
2440	for (int i = 0; i < 6; ++ i)
2441	{
2442	VertexContainer vertices;
2443
2444	for (int j = 0; j < 4; ++ j)
2445	vertices.push_back(mBbox.GetFace(i).mVertices[j]);
2446
2447	Polygon3 *poly = new Polygon3(vertices);
2448
2449	candidatePolys.push_back(poly);
2450	candidatePlanes.push_back(poly->GetSupportingPlane());
2451	}
2452
2453	for (int i = 0; i < (int)candidatePolys.size(); ++ i)
2454	{
2455	// polygon is split by all other planes
2456	for (int j = 0; (j < (int)halfSpaces.size()) && candidatePolys[i]; ++ j)
2457	{
2458	if (i == j) // polygon and plane are coincident
2459	continue;
2460
2461	VertexContainer splitPts;
2462	Polygon3 frontPoly, backPoly;
2463
2464	const int cf =
2465	candidatePolys[i]->ClassifyPlane(halfSpaces[j],
2466	mEpsilon);
2467
2468	switch (cf)
2469	{
2470	case Polygon3::SPLIT:
2471	frontPoly = new Polygon3();
2472	backPoly = new Polygon3();
2473
2474	candidatePolys[i]->Split(halfSpaces[j],
2475	*frontPoly,
2476	*backPoly,
2477	mEpsilon);
2478
2479	DEL_PTR(candidatePolys[i]);
2480
2481	if (backPoly->Valid(mEpsilon))
2482	candidatePolys[i] = backPoly;
2483	else
2484	DEL_PTR(backPoly);
2485
2486	// outside, don't need this
2487	DEL_PTR(frontPoly);
2488	break;
2489	// polygon outside of halfspace
2490	case Polygon3::FRONT_SIDE:
2491	DEL_PTR(candidatePolys[i]);
2492	break;
2493	// just take polygon as it is
2494	case Polygon3::BACK_SIDE:
2495	case Polygon3::COINCIDENT:
2496	default:
2497	break;
2498	}
2499	}
2500
2501	if (candidatePolys[i])
2502	{
2503	geom.Add(candidatePolys[i], candidatePlanes[i]);
2504	}
2505	}
2506	}
2507
2508
2509	void BspTree::SetViewCellsManager(ViewCellsManager *vcm)
2510	{
2511	mViewCellsManager = vcm;
2512	}
2513
2514
2515	typedef pair<BspNode , BspNodeGeometry > bspNodePair;
2516
2517
2518	int BspTree::FindNeighbors(BspNode *n,
2519	vector<BspLeaf *> &neighbors,
2520	const bool onlyUnmailed) const
2521	{
2522	stack<bspNodePair> nodeStack;
2523
2524	BspNodeGeometry nodeGeom;
2525	ConstructGeometry(n, nodeGeom);
2526
2527	// split planes from the root to this node
2528	// needed to verify that we found neighbor leaf
2529	// TODO: really needed?
2530	vector<Plane3> halfSpaces;
2531	ExtractHalfSpaces(n, halfSpaces);
2532
2533
2534	BspNodeGeometry *rgeom = new BspNodeGeometry();
2535	ConstructGeometry(mRoot, *rgeom);
2536
2537	nodeStack.push(bspNodePair(mRoot, rgeom));
2538
2539	while (!nodeStack.empty())
2540	{
2541	BspNode *node = nodeStack.top().first;
2542	BspNodeGeometry *geom = nodeStack.top().second;
2543
2544	nodeStack.pop();
2545
2546	if (node->IsLeaf())
2547	{
2548	// test if this leaf is in valid view space
2549	if (node->TreeValid() &&
2550	(node != n) &&
2551	(!onlyUnmailed \|\| !node->Mailed()))
2552	{
2553	bool isAdjacent = true;
2554
2555	if (1)
2556	{
2557	// test all planes of current node if still adjacent
2558	for (int i = 0; (i < halfSpaces.size()) && isAdjacent; ++ i)
2559	{
2560	const int cf =
2561	Polygon3::ClassifyPlane(geom->GetPolys(),
2562	halfSpaces[i],
2563	mEpsilon);
2564
2565	if (cf == Polygon3::FRONT_SIDE)
2566	{
2567	isAdjacent = false;
2568	}
2569	}
2570	}
2571	else
2572	{
2573	// TODO: why is this wrong??
2574	// test all planes of current node if still adjacent
2575	for (int i = 0; (i < nodeGeom.Size()) && isAdjacent; ++ i)
2576	{
2577	Polygon3 *poly = nodeGeom.GetPolys()[i];
2578
2579	const int cf =
2580	Polygon3::ClassifyPlane(geom->GetPolys(),
2581	poly->GetSupportingPlane(),
2582	mEpsilon);
2583
2584	if (cf == Polygon3::FRONT_SIDE)
2585	{
2586	isAdjacent = false;
2587	}
2588	}
2589	}
2590	// neighbor was found
2591	if (isAdjacent)
2592	{
2593	neighbors.push_back(dynamic_cast<BspLeaf *>(node));
2594	}
2595	}
2596	}
2597	else
2598	{
2599	BspInterior interior = dynamic_cast<BspInterior >(node);
2600
2601	const int cf = Polygon3::ClassifyPlane(nodeGeom.GetPolys(),
2602	interior->GetPlane(),
2603	mEpsilon);
2604
2605	BspNode *front = interior->GetFront();
2606	BspNode *back = interior->GetBack();
2607
2608	BspNodeGeometry *fGeom = new BspNodeGeometry();
2609	BspNodeGeometry *bGeom = new BspNodeGeometry();
2610
2611	geom->SplitGeometry(*fGeom,
2612	*bGeom,
2613	interior->GetPlane(),
2614	mBbox,
2615	//0.0000001f);
2616	mEpsilon);
2617
2618	if (cf == Polygon3::BACK_SIDE)
2619	{
2620	nodeStack.push(bspNodePair(interior->GetBack(), bGeom));
2621	DEL_PTR(fGeom);
2622	}
2623	else
2624	{
2625	if (cf == Polygon3::FRONT_SIDE)
2626	{
2627	nodeStack.push(bspNodePair(interior->GetFront(), fGeom));
2628	DEL_PTR(bGeom);
2629	}
2630	else
2631	{ // random decision
2632	nodeStack.push(bspNodePair(front, fGeom));
2633	nodeStack.push(bspNodePair(back, bGeom));
2634	}
2635	}
2636	}
2637
2638	DEL_PTR(geom);
2639	}
2640
2641	return (int)neighbors.size();
2642	}
2643
2644
2645	BspLeaf *BspTree::GetRandomLeaf(const bool onlyUnmailed)
2646	{
2647	stack<BspNode *> nodeStack;
2648
2649	nodeStack.push(mRoot);
2650
2651	int mask = rand();
2652
2653	while (!nodeStack.empty())
2654	{
2655	BspNode *node = nodeStack.top();
2656	nodeStack.pop();
2657
2658	if (node->IsLeaf())
2659	{
2660	if ( (!onlyUnmailed \|\| !node->Mailed()) )
2661	return dynamic_cast<BspLeaf *>(node);
2662	}
2663	else
2664	{
2665	BspInterior interior = dynamic_cast<BspInterior >(node);
2666
2667	// random decision
2668	if (mask & 1)
2669	nodeStack.push(interior->GetBack());
2670	else
2671	nodeStack.push(interior->GetFront());
2672
2673	mask = mask >> 1;
2674	}
2675	}
2676
2677	return NULL;
2678	}
2679
2680
2681	void BspTree::AddToPvs(BspLeaf *leaf,
2682	const BoundedRayContainer &rays,
2683	int &sampleContributions,
2684	int &contributingSamples)
2685	{
2686	sampleContributions = 0;
2687	contributingSamples = 0;
2688
2689	BoundedRayContainer::const_iterator it, it_end = rays.end();
2690
2691	ViewCellLeaf *vc = leaf->GetViewCell();
2692
2693	// add contributions from samples to the PVS
2694	for (it = rays.begin(); it != it_end; ++ it)
2695	{
2696	int contribution = 0;
2697	Ray ray = (it)->mRay;
2698	float relContribution;
2699	if (!ray->intersections.empty())
2700	contribution += vc->GetPvs().AddSample(ray->intersections[0].mObject,
2701	1.0f);
2702	//relContribution);
2703
2704	if (ray->sourceObject.mObject)
2705	contribution += vc->GetPvs().AddSample(ray->sourceObject.mObject,
2706	1.0f);
2707	//relContribution);
2708
2709	if (contribution)
2710	{
2711	sampleContributions += contribution;
2712	++ contributingSamples;
2713	}
2714
2715	//if (ray->mFlags & Ray::STORE_BSP_INTERSECTIONS)
2716	// ray->bspIntersections.push_back(Ray::BspIntersection((*it)->mMinT, this));
2717	}
2718	}
2719
2720
2721	int BspTree::ComputePvsSize(const BoundedRayContainer &rays) const
2722	{
2723	int pvsSize = 0;
2724
2725	BoundedRayContainer::const_iterator rit, rit_end = rays.end();
2726
2727	Intersectable::NewMail();
2728
2729	for (rit = rays.begin(); rit != rays.end(); ++ rit)
2730	{
2731	Ray ray = (rit)->mRay;
2732
2733	if (!ray->intersections.empty())
2734	{
2735	if (!ray->intersections[0].mObject->Mailed())
2736	{
2737	ray->intersections[0].mObject->Mail();
2738	++ pvsSize;
2739	}
2740	}
2741	if (ray->sourceObject.mObject)
2742	{
2743	if (!ray->sourceObject.mObject->Mailed())
2744	{
2745	ray->sourceObject.mObject->Mail();
2746	++ pvsSize;
2747	}
2748	}
2749	}
2750
2751	return pvsSize;
2752	}
2753
2754
2755	float BspTree::GetEpsilon() const
2756	{
2757	return mEpsilon;
2758	}
2759
2760
2761	int BspTree::CollectMergeCandidates(const vector<BspLeaf *> leaves,
2762	vector<MergeCandidate> &candidates)
2763	{
2764	BspLeaf::NewMail();
2765
2766	vector<BspLeaf *>::const_iterator it, it_end = leaves.end();
2767
2768	int numCandidates = 0;
2769
2770	// find merge candidates and push them into queue
2771	for (it = leaves.begin(); it != it_end; ++ it)
2772	{
2773	BspLeaf leaf = it;
2774
2775	// the same leaves must not be part of two merge candidates
2776	leaf->Mail();
2777	vector<BspLeaf *> neighbors;
2778	FindNeighbors(leaf, neighbors, true);
2779
2780	vector<BspLeaf *>::const_iterator nit, nit_end = neighbors.end();
2781
2782	// TODO: test if at least one ray goes from one leaf to the other
2783	for (nit = neighbors.begin(); nit != nit_end; ++ nit)
2784	{
2785	if ((*nit)->GetViewCell() != leaf->GetViewCell())
2786	{
2787	MergeCandidate mc(leaf->GetViewCell(), (*nit)->GetViewCell());
2788	candidates.push_back(mc);
2789
2790	++ numCandidates;
2791	if ((numCandidates % 1000) == 0)
2792	{
2793	cout << "collected " << numCandidates << " merge candidates" << endl;
2794	}
2795	}
2796	}
2797	}
2798
2799	Debug << "merge queue: " << (int)candidates.size() << endl;
2800	Debug << "leaves in queue: " << numCandidates << endl;
2801
2802
2803	return (int)leaves.size();
2804	}
2805
2806
2807	int BspTree::CollectMergeCandidates(const VssRayContainer &rays,
2808	vector<MergeCandidate> &candidates)
2809	{
2810	ViewCell::NewMail();
2811	long startTime = GetTime();
2812
2813	map<BspLeaf , vector<BspLeaf> > neighborMap;
2814	ViewCellContainer::const_iterator iit;
2815
2816	int numLeaves = 0;
2817
2818	BspLeaf::NewMail();
2819
2820	for (int i = 0; i < (int)rays.size(); ++ i)
2821	{
2822	VssRay *ray = rays[i];
2823
2824	// traverse leaves stored in the rays and compare and
2825	// merge consecutive leaves (i.e., the neighbors in the tree)
2826	if (ray->mViewCells.size() < 2)
2827	continue;
2828
2829	iit = ray->mViewCells.begin();
2830	BspViewCell bspVc = dynamic_cast<BspViewCell >(*(iit ++));
2831	BspLeaf *leaf = bspVc->mLeaves[0];
2832
2833	// traverse intersections
2834	// consecutive leaves are neighbors => add them to queue
2835	for (; iit != ray->mViewCells.end(); ++ iit)
2836	{
2837	// next pair
2838	BspLeaf *prevLeaf = leaf;
2839	bspVc = dynamic_cast<BspViewCell >(iit);
2840	leaf = bspVc->mLeaves[0];
2841
2842	// view space not valid or same view cell
2843	if (!leaf->TreeValid() \|\| !prevLeaf->TreeValid() \|\|
2844	(leaf->GetViewCell() == prevLeaf->GetViewCell()))
2845	continue;
2846
2847	vector<BspLeaf *> &neighbors = neighborMap[leaf];
2848
2849	bool found = false;
2850
2851	// both leaves inserted in queue already =>
2852	// look if double pair already exists
2853	if (leaf->Mailed() && prevLeaf->Mailed())
2854	{
2855	vector<BspLeaf *>::const_iterator it, it_end = neighbors.end();
2856
2857	for (it = neighbors.begin(); !found && (it != it_end); ++ it)
2858	if (*it == prevLeaf)
2859	found = true; // already in queue
2860	}
2861
2862	if (!found)
2863	{
2864	// this pair is not in map yet
2865	// => insert into the neighbor map and the queue
2866	neighbors.push_back(prevLeaf);
2867	neighborMap[prevLeaf].push_back(leaf);
2868
2869	leaf->Mail();
2870	prevLeaf->Mail();
2871
2872	MergeCandidate mc(leaf->GetViewCell(), prevLeaf->GetViewCell());
2873
2874	candidates.push_back(mc);
2875
2876	if (((int)candidates.size() % 1000) == 0)
2877	{
2878	cout << "collected " << (int)candidates.size() << " merge candidates" << endl;
2879	}
2880	}
2881	}
2882	}
2883
2884	Debug << "neighbormap size: " << (int)neighborMap.size() << endl;
2885	Debug << "merge queue: " << (int)candidates.size() << endl;
2886	Debug << "leaves in queue: " << numLeaves << endl;
2887
2888	#if 0
2889	//////////
2890	//-- collect the leaves which haven't been found by ray casting
2891	cout << "finding additional merge candidates using geometry" << endl;
2892	vector<BspLeaf *> leaves;
2893	CollectLeaves(leaves, true);
2894	Debug << "found " << (int)leaves.size() << " new leaves" << endl << endl;
2895	CollectMergeCandidates(leaves, candidates);
2896	#endif
2897
2898	return numLeaves;
2899	}
2900
2901
2902
2903	/***************************************************************/
2904	/* BspNodeGeometry Implementation */
2905	/***************************************************************/
2906
2907
2908	BspNodeGeometry::BspNodeGeometry(const BspNodeGeometry &rhs)
2909	{
2910	mPolys.reserve(rhs.mPolys.size());
2911	mPlanes.reserve(rhs.mPolys.size());
2912
2913	PolygonContainer::const_iterator it, it_end = rhs.mPolys.end();
2914
2915	int i = 0;
2916
2917	for (it = rhs.mPolys.begin(); it != it_end; ++ it, ++i)
2918	{
2919	Polygon3 poly = it;
2920	Add(new Polygon3(*poly), rhs.mPlanes[i]);
2921	}
2922	}
2923
2924
2925	BspNodeGeometry& BspNodeGeometry::operator=(const BspNodeGeometry& g)
2926	{
2927	if (this == &g)
2928	return *this;
2929
2930	CLEAR_CONTAINER(mPolys);
2931
2932	mPolys.reserve(g.mPolys.size());
2933	mPlanes.reserve(g.mPolys.size());
2934
2935	PolygonContainer::const_iterator it, it_end = g.mPolys.end();
2936
2937	int i = 0;
2938
2939	for (it = g.mPolys.begin(); it != it_end; ++ it, ++ i)
2940	{
2941	Polygon3 poly = it;
2942	Add(new Polygon3(*poly), g.mPlanes[i]);
2943	}
2944
2945	return *this;
2946	}
2947
2948
2949	BspNodeGeometry::BspNodeGeometry(const PolygonContainer &polys)
2950	{
2951	mPolys = polys;
2952	mPlanes.reserve(polys.size());
2953
2954	PolygonContainer::const_iterator it, it_end = polys.end();
2955
2956	for (it = polys.begin(); it != it_end; ++ it)
2957	{
2958	Polygon3 poly = it;
2959	mPlanes.push_back(poly->GetSupportingPlane());
2960	}
2961	}
2962
2963
2964	BspNodeGeometry::~BspNodeGeometry()
2965	{
2966	CLEAR_CONTAINER(mPolys);
2967	}
2968
2969
2970	int BspNodeGeometry::Size() const
2971	{
2972	return (int)mPolys.size();
2973	}
2974
2975
2976	const PolygonContainer &BspNodeGeometry::GetPolys()
2977	{
2978	return mPolys;
2979	}
2980
2981
2982	void BspNodeGeometry::Add(Polygon3 *p, const Plane3 &plane)
2983	{
2984	mPolys.push_back(p);
2985	mPlanes.push_back(plane);
2986	}
2987
2988
2989	float BspNodeGeometry::GetArea() const
2990	{
2991	return Polygon3::GetArea(mPolys);
2992	}
2993
2994
2995	float BspNodeGeometry::GetVolume() const
2996	{
2997	//-- compute volume using tetrahedralization of the geometry
2998	// and adding the volume of the single tetrahedrons
2999	float volume = 0;
3000	const float f = 1.0f / 6.0f;
3001
3002	PolygonContainer::const_iterator pit, pit_end = mPolys.end();
3003
3004	// note: can take arbitrary point, e.g., the origin. However,
3005	// we rather take the center of mass to prevents precision errors
3006	const Vector3 center = CenterOfMass();
3007
3008	for (pit = mPolys.begin(); pit != pit_end; ++ pit)
3009	{
3010	Polygon3 poly = pit;
3011	const Vector3 v0 = poly->mVertices[0] - center;
3012
3013	for (int i = 1; i < (int)poly->mVertices.size() - 1; ++ i)
3014	{
3015	const Vector3 v1 = poly->mVertices[i] - center;
3016	const Vector3 v2 = poly->mVertices[i + 1] - center;
3017
3018	// more robust version using abs and the center of mass
3019	volume += fabs (f * (DotProd(v0, CrossProd(v1, v2))));
3020	}
3021	}
3022
3023	return volume;
3024	}
3025
3026
3027	void BspNodeGeometry::GetBoundingBox(AxisAlignedBox3 &box) const
3028	{
3029	box.Initialize();
3030	box.Include(mPolys);
3031	}
3032
3033
3034	int BspNodeGeometry::Side(const Plane3 &plane, const float eps) const
3035	{
3036	PolygonContainer::const_iterator it, it_end = mPolys.end();
3037
3038	bool onFrontSide = false;
3039	bool onBackSide = false;
3040
3041	for (it = mPolys.begin(); it != it_end; ++ it)
3042	{
3043	const int side = (*it)->Side(plane, eps);
3044
3045	if (side == -1)
3046	onBackSide = true;
3047	else if (side == 1)
3048	onFrontSide = true;
3049
3050	if ((side == 0) \|\| (onBackSide && onFrontSide))
3051	return 0;
3052	}
3053
3054	if (onFrontSide)
3055	return 1;
3056
3057	return -1;
3058	}
3059
3060
3061	int BspNodeGeometry::ComputeIntersection(const AxisAlignedBox3 &box) const
3062	{
3063	// 1: box does not intersect geometry
3064	// 0: box intersects geometry
3065	// -1: box contains geometry
3066
3067	AxisAlignedBox3 boundingBox;
3068	GetBoundingBox(boundingBox);
3069
3070	// no intersections with bounding box
3071	if (!Overlap(box, boundingBox))
3072	{
3073	return 1;
3074	}
3075
3076	// box cotains bounding box of geometry >=> contains geometry
3077	if (box.Includes(boundingBox))
3078	return -1;
3079
3080	int result = 0;
3081
3082	// test geometry planes for intersections
3083	vector<Plane3>::const_iterator it, it_end = mPlanes.end();
3084
3085	for (it = mPlanes.begin(); it != it_end; ++ it)
3086	{
3087	const int side = box.Side(*it);
3088
3089	// box does not intersects geometry
3090	if (side == 1)
3091	{
3092	return 1;
3093	}
3094	//if (side == 0) result = 0;
3095	}
3096
3097	return result;
3098	}
3099
3100
3101	Vector3 BspNodeGeometry::CenterOfMass() const
3102	{
3103	int n = 0;
3104
3105	Vector3 center(0,0,0);
3106
3107	PolygonContainer::const_iterator pit, pit_end = mPolys.end();
3108
3109	for (pit = mPolys.begin(); pit != pit_end; ++ pit)
3110	{
3111	Polygon3 poly = pit;
3112
3113	VertexContainer::const_iterator vit, vit_end = poly->mVertices.end();
3114
3115	for(vit = poly->mVertices.begin(); vit != vit_end; ++ vit)
3116	{
3117	center += *vit;
3118	++ n;
3119	}
3120	}
3121
3122	//Debug << "center: " << center << " new " << center / (float)n << endl;
3123
3124	return center / (float)n;
3125	}
3126
3127
3128	bool BspNodeGeometry::Valid() const
3129	{
3130	// geometry is degenerated
3131	if (mPolys.size() < 4)
3132	return false;
3133
3134	return true;
3135	}
3136
3137	void IncludeNodeGeomInMesh(const BspNodeGeometry &geom, Mesh &mesh)
3138	{
3139	// add single polygons to mesh
3140	PolygonContainer::const_iterator it, it_end = geom.mPolys.end();
3141
3142	for (it = geom.mPolys.begin(); it != geom.mPolys.end(); ++ it)
3143	{
3144	Polygon3 poly = (it);
3145	IncludePolyInMesh(*poly, mesh);
3146	}
3147	}
3148
3149
3150	bool BspNodeGeometry::SplitGeometry(BspNodeGeometry &front,
3151	BspNodeGeometry &back,
3152	const Plane3 &splitPlane,
3153	const AxisAlignedBox3 &box,
3154	const float epsilon) const
3155	{
3156	//-- trivial cases
3157	if (0)
3158	{
3159	const int cf = Side(splitPlane, epsilon);
3160
3161	if (cf == -1)
3162	{
3163	back = *this;
3164	return false;
3165	}
3166	else if (cf == 1)
3167	{
3168	front = *this;
3169	return false;
3170	}
3171	}
3172
3173	// get cross section of new polygon
3174	Polygon3 *planePoly = box.CrossSection(splitPlane);
3175
3176	// split polygon with all other polygons
3177	planePoly = SplitPolygon(planePoly, epsilon);
3178
3179	bool splitsGeom = (planePoly != NULL);
3180
3181	//-- new polygon splits all other polygons
3182	for (int i = 0; i < (int)mPolys.size()/* && planePoly*/; ++ i)
3183	{
3184	/// don't use epsilon here to get exact split planes
3185	const int cf =
3186	mPolys[i]->ClassifyPlane(splitPlane, epsilon);
3187
3188	switch (cf)
3189	{
3190	case Polygon3::SPLIT:
3191	{
3192	Polygon3 *poly = new Polygon3(mPolys[i]->mVertices);
3193
3194	Polygon3 *frontPoly = new Polygon3();
3195	Polygon3 *backPoly = new Polygon3();
3196
3197	poly->Split(splitPlane,
3198	*frontPoly,
3199	*backPoly,
3200	epsilon);
3201
3202	DEL_PTR(poly);
3203
3204	if (frontPoly->Valid(epsilon))
3205	{
3206	front.Add(frontPoly, mPlanes[i]);
3207	}
3208	else
3209	{
3210	//Debug << "no f! " << endl;
3211	DEL_PTR(frontPoly);
3212	}
3213
3214	if (backPoly->Valid(epsilon))
3215	{
3216	back.Add(backPoly, mPlanes[i]);
3217	}
3218	else
3219	{
3220	//Debug << "no b! " << endl;
3221	DEL_PTR(backPoly);
3222	}
3223	}
3224
3225	break;
3226	case Polygon3::BACK_SIDE:
3227	back.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3228	break;
3229	case Polygon3::FRONT_SIDE:
3230	front.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3231	break;
3232	// only put into back container (split should have no effect ...)
3233	case Polygon3::COINCIDENT:
3234	//Debug << "error should not come here" << endl;
3235	splitsGeom = false;
3236
3237	if (DotProd(mPlanes[i].mNormal, splitPlane.mNormal > 0))
3238	back.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3239	else
3240	front.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3241	break;
3242	default:
3243	break;
3244	}
3245	}
3246
3247	//-- finally add the new polygon to the child node geometries
3248	if (planePoly)
3249	{
3250	// add polygon with reverse orientation to front cell
3251	Plane3 reversePlane(splitPlane);
3252	reversePlane.ReverseOrientation();
3253
3254	// add polygon with normal pointing into positive half space to back cell
3255	back.Add(planePoly, splitPlane);
3256	//back.mPolys.push_back(planePoly);
3257
3258	Polygon3 *reversePoly = planePoly->CreateReversePolygon();
3259	front.Add(reversePoly, reversePlane);
3260	//Debug << "poly normal : " << reversePoly->GetSupportingPlane().mNormal << " split plane normal " << reversePlane.mNormal << endl;
3261	}
3262
3263
3264	return splitsGeom;
3265	}
3266
3267
3268	Polygon3 BspNodeGeometry::SplitPolygon(Polygon3 planePoly,
3269	const float epsilon) const
3270	{
3271	if (!planePoly->Valid(epsilon))
3272	{
3273	//Debug << "not valid!!" << endl;
3274	DEL_PTR(planePoly);
3275	}
3276	// polygon is split by all other planes
3277	for (int i = 0; (i < (int)mPolys.size()) && planePoly; ++ i)
3278	{
3279	//Plane3 plane = mPolys[i]->GetSupportingPlane();
3280	Plane3 plane = mPlanes[i];
3281
3282	/// don't use epsilon here to get exact split planes
3283	const int cf =
3284	planePoly->ClassifyPlane(plane, epsilon);
3285
3286	// split new polygon with all previous planes
3287	switch (cf)
3288	{
3289	case Polygon3::SPLIT:
3290	{
3291	Polygon3 *frontPoly = new Polygon3();
3292	Polygon3 *backPoly = new Polygon3();
3293
3294	planePoly->Split(plane,
3295	*frontPoly,
3296	*backPoly,
3297	epsilon);
3298
3299	// don't need anymore
3300	DEL_PTR(planePoly);
3301	DEL_PTR(frontPoly);
3302
3303	// back polygon is belonging to geometry
3304	if (backPoly->Valid(epsilon))
3305	planePoly = backPoly;
3306	else
3307	DEL_PTR(backPoly);
3308	}
3309	break;
3310	case Polygon3::FRONT_SIDE:
3311	DEL_PTR(planePoly);
3312	break;
3313	// polygon is taken as it is
3314	case Polygon3::BACK_SIDE:
3315	case Polygon3::COINCIDENT:
3316	default:
3317	break;
3318	}
3319	}
3320
3321	return planePoly;
3322	}
3323
3324
3325	ViewCell *BspTree::GetViewCell(const Vector3 &point)
3326	{
3327	if (mRoot == NULL)
3328	return NULL;
3329
3330	stack<BspNode *> nodeStack;
3331	nodeStack.push(mRoot);
3332
3333	ViewCellLeaf *viewcell = NULL;
3334
3335	while (!nodeStack.empty()) {
3336	BspNode *node = nodeStack.top();
3337	nodeStack.pop();
3338
3339	if (node->IsLeaf())
3340	{
3341	viewcell = dynamic_cast<BspLeaf *>(node)->mViewCell;
3342	break;
3343	}
3344	else
3345	{
3346
3347	BspInterior interior = dynamic_cast<BspInterior >(node);
3348
3349	// random decision
3350	if (interior->GetPlane().Side(point) < 0)
3351	{
3352	nodeStack.push(interior->GetBack());
3353	}
3354	else
3355	{
3356	nodeStack.push(interior->GetFront());
3357	}
3358	}
3359	}
3360
3361	return viewcell;
3362	}
3363
3364
3365	bool BspTree::Export(OUT_STREAM &stream)
3366	{
3367	ExportNode(mRoot, stream);
3368	return true;
3369	}
3370
3371
3372	void BspTree::ExportNode(BspNode *node, OUT_STREAM &stream)
3373	{
3374	if (node->IsLeaf())
3375	{
3376	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3377	ViewCell *viewCell = mViewCellsTree->GetActiveViewCell(leaf->GetViewCell());
3378
3379	const int id = viewCell->GetId();
3380
3381	stream << "<Leaf viewCellId=\"" << id << "\" />" << endl;
3382	}
3383	else
3384	{
3385	BspInterior interior = dynamic_cast<BspInterior >(node);
3386
3387	Plane3 plane = interior->GetPlane();
3388	stream << "<Interior plane=\"" << plane.mNormal.x << " "
3389	<< plane.mNormal.y << " " << plane.mNormal.z << " "
3390	<< plane.mD << "\">" << endl;
3391
3392	ExportNode(interior->GetBack(), stream);
3393	ExportNode(interior->GetFront(), stream);
3394
3395	stream << "</Interior>" << endl;
3396	}
3397	}
3398
3399
3400	}

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