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source: GTP/trunk/Lib/Vis/Preprocessing/src/ViewCellBsp.cpp @ 1564

Revision 1564, 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 _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 first extracting polygons
727	// and take 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	// from now on out of bounds cell can be handled as any other cell,
1020	// responsibility for deleting has been shifted
1021	if (IsOutOfBounds(viewCell))
1022	{
1023	mOutOfBoundsCellPartOfTree = true;
1024	}
1025
1026	}
1027
1028	leaf->SetViewCell(viewCell);
1029	viewCell->mLeaves.push_back(leaf);
1030
1031	//float probability = max(0.0f, tData.mProbability);
1032	float probability = tData.mProbability;
1033
1034	if (mUseAreaForPvs)
1035	viewCell->SetArea(probability);
1036	else
1037	viewCell->SetVolume(probability);
1038
1039	///////////
1040	//-- add pvs contribution of rays
1041
1042	if (viewCell != mOutOfBoundsCell)
1043	{
1044	int conSamp = 0, sampCon = 0;
1045	AddToPvs(leaf, *tData.mRays, conSamp, sampCon);
1046
1047	mStat.contributingSamples += conSamp;
1048	mStat.sampleContributions += sampCon;
1049	}
1050
1051	if (1) EvaluateLeafStats(tData);
1052
1053	////////
1054	//-- clean up
1055
1056	// discard polygons
1057	CLEAR_CONTAINER(*tData.mPolygons);
1058	// discard rays
1059	CLEAR_CONTAINER(*tData.mRays);
1060
1061	delete tData.mPolygons;
1062	delete tData.mRays;
1063	delete tData.mGeometry;
1064
1065	return leaf;
1066	}
1067
1068	///////////
1069	//-- continue subdivision
1070
1071	PolygonContainer coincident;
1072
1073	BspTraversalData tFrontData(NULL, new PolygonContainer(), tData.mDepth + 1, mOutOfBoundsCell,
1074	new BoundedRayContainer(), 0, 0, new BspNodeGeometry());
1075	BspTraversalData tBackData(NULL, new PolygonContainer(), tData.mDepth + 1, mOutOfBoundsCell,
1076	new BoundedRayContainer(), 0, 0, new BspNodeGeometry());
1077
1078
1079	// create new interior node and two leaf nodes
1080	BspInterior *interior =
1081	SubdivideNode(tData, tFrontData, tBackData, coincident);
1082
1083	if (1)
1084	{
1085	int pvsData = tData.mPvs;
1086
1087	float cData = (float)pvsData * tData.mProbability;
1088	float cFront = (float)tFrontData.mPvs * tFrontData.mProbability;
1089	float cBack = (float)tBackData.mPvs * tBackData.mProbability;
1090
1091	float costDecr = (cFront + cBack - cData) / mBbox.GetVolume();
1092
1093	mTotalCost += costDecr;
1094	mTotalPvsSize += tFrontData.mPvs + tBackData.mPvs - pvsData;
1095
1096	mSubdivisionStats
1097	<< "#ViewCells\n" << mStat.Leaves() << endl
1098	<< "#RenderCostDecrease\n" << -costDecr << endl
1099	<< "#TotalRenderCost\n" << mTotalCost << endl
1100	<< "#AvgRenderCost\n" << mTotalPvsSize / mStat.Leaves() << endl;
1101	}
1102
1103	// extract view cells from coincident polygons
1104	// with respect to the orientation of their normal
1105	// note: if front or back polygons are empty,
1106	// we get the valid in - out classification for the view cell
1107
1108	if (mUsePredefinedViewCells)
1109	{
1110	ExtractViewCells(tFrontData,
1111	tBackData,
1112	coincident,
1113	interior->mPlane);
1114	}
1115
1116	// don't need coincident polygons anymory
1117	CLEAR_CONTAINER(coincident);
1118
1119	// push the children on the stack
1120	tStack.push(tFrontData);
1121	tStack.push(tBackData);
1122
1123	////////
1124	//-- cleanup
1125
1126	DEL_PTR(tData.mNode);
1127	DEL_PTR(tData.mPolygons);
1128	DEL_PTR(tData.mRays);
1129	DEL_PTR(tData.mGeometry);
1130
1131	return interior;
1132	}
1133
1134
1135	void BspTree::ExtractViewCells(BspTraversalData &frontData,
1136	BspTraversalData &backData,
1137	const PolygonContainer &coincident,
1138	const Plane3 &splitPlane) const
1139	{
1140	// if not empty, tree is further subdivided => don't have to find view cell
1141	bool foundFront = !frontData.mPolygons->empty();
1142	bool foundBack = !frontData.mPolygons->empty();
1143
1144	PolygonContainer::const_iterator it =
1145	coincident.begin(), it_end = coincident.end();
1146
1147	//////////
1148	//-- find first view cells in front and back leafs
1149
1150	for (; !(foundFront && foundBack) && (it != it_end); ++ it)
1151	{
1152	if (DotProd((*it)->GetNormal(), splitPlane.mNormal) > 0)
1153	{
1154	backData.mViewCell = dynamic_cast<ViewCellLeaf >((it)->mParent);
1155	foundBack = true;
1156	}
1157	else
1158	{
1159	frontData.mViewCell = dynamic_cast<ViewCellLeaf >((it)->mParent);
1160	foundFront = true;
1161	}
1162	}
1163	}
1164
1165
1166	BspInterior *BspTree::SubdivideNode(BspTraversalData &tData,
1167	BspTraversalData &frontData,
1168	BspTraversalData &backData,
1169	PolygonContainer &coincident)
1170	{
1171	mStat.nodes += 2;
1172
1173	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
1174
1175	// select subdivision plane
1176	BspInterior *interior = new BspInterior(SelectPlane(leaf, tData));
1177
1178	#ifdef _DEBUG
1179	Debug << interior << endl;
1180	#endif
1181
1182	// subdivide rays into front and back rays
1183	SplitRays(interior->mPlane, tData.mRays, frontData.mRays, *backData.mRays);
1184
1185	// subdivide polygons with plane
1186	mStat.polySplits += SplitPolygons(interior->GetPlane(),
1187	*tData.mPolygons,
1188	*frontData.mPolygons,
1189	*backData.mPolygons,
1190	coincident);
1191
1192
1193	// compute pvs
1194	frontData.mPvs = ComputePvsSize(*frontData.mRays);
1195	backData.mPvs = ComputePvsSize(*backData.mRays);
1196
1197	// split geometry and compute area
1198	if (1)
1199	{
1200	tData.mGeometry->SplitGeometry(*frontData.mGeometry,
1201	*backData.mGeometry,
1202	interior->mPlane,
1203	mBbox,
1204	//0.000000000001);
1205	mEpsilon);
1206
1207
1208	if (mUseAreaForPvs)
1209	{
1210	frontData.mProbability = frontData.mGeometry->GetArea();
1211	backData.mProbability = backData.mGeometry->GetArea();
1212	}
1213	else
1214	{
1215	frontData.mProbability = frontData.mGeometry->GetVolume();
1216	backData.mProbability = tData.mProbability - frontData.mProbability;
1217	}
1218	}
1219
1220	//-- create front and back leaf
1221
1222	BspInterior *parent = leaf->GetParent();
1223
1224	// replace a link from node's parent
1225	if (!leaf->IsRoot())
1226	{
1227	parent->ReplaceChildLink(leaf, interior);
1228	interior->SetParent(parent);
1229	}
1230	else // new root
1231	{
1232	mRoot = interior;
1233	}
1234
1235	// and setup child links
1236	interior->SetupChildLinks(new BspLeaf(interior), new BspLeaf(interior));
1237
1238	frontData.mNode = interior->GetFront();
1239	backData.mNode = interior->GetBack();
1240
1241	interior->mTimeStamp = mTimeStamp ++;
1242
1243	//DEL_PTR(leaf);
1244	return interior;
1245	}
1246
1247
1248	void BspTree::SortSubdivisionCandidates(const PolygonContainer &polys,
1249	const int axis,
1250	vector<SortableEntry> &splitCandidates) const
1251	{
1252	splitCandidates.clear();
1253
1254	int requestedSize = 2 * (int)polys.size();
1255	// creates a sorted split candidates array
1256	splitCandidates.reserve(requestedSize);
1257
1258	PolygonContainer::const_iterator it, it_end = polys.end();
1259
1260	AxisAlignedBox3 box;
1261
1262	// insert all queries
1263	for(it = polys.begin(); it != it_end; ++ it)
1264	{
1265	box.Initialize();
1266	box.Include((it));
1267
1268	splitCandidates.push_back(SortableEntry(SortableEntry::POLY_MIN, box.Min(axis), *it));
1269	splitCandidates.push_back(SortableEntry(SortableEntry::POLY_MAX, box.Max(axis), *it));
1270	}
1271
1272	stable_sort(splitCandidates.begin(), splitCandidates.end());
1273	}
1274
1275
1276	float BspTree::BestCostRatio(const PolygonContainer &polys,
1277	const AxisAlignedBox3 &box,
1278	const int axis,
1279	float &position,
1280	int &objectsBack,
1281	int &objectsFront) const
1282	{
1283	vector<SortableEntry> splitCandidates;
1284
1285	SortSubdivisionCandidates(polys, axis, splitCandidates);
1286
1287	// go through the lists, count the number of objects left and right
1288	// and evaluate the following cost funcion:
1289	// C = ct_div_ci + (ol + or)/queries
1290
1291	int objectsLeft = 0, objectsRight = (int)polys.size();
1292
1293	float minBox = box.Min(axis);
1294	float maxBox = box.Max(axis);
1295	float boxArea = box.SurfaceArea();
1296
1297	float minBand = minBox + mSplitBorder * (maxBox - minBox);
1298	float maxBand = minBox + (1.0f - mSplitBorder) * (maxBox - minBox);
1299
1300	float minSum = 1e20f;
1301	vector<SortableEntry>::const_iterator ci, ci_end = splitCandidates.end();
1302
1303	for(ci = splitCandidates.begin(); ci != ci_end; ++ ci)
1304	{
1305	switch ((*ci).type)
1306	{
1307	case SortableEntry::POLY_MIN:
1308	++ objectsLeft;
1309	break;
1310	case SortableEntry::POLY_MAX:
1311	-- objectsRight;
1312	break;
1313	default:
1314	break;
1315	}
1316
1317	if ((ci).value > minBand && (ci).value < maxBand)
1318	{
1319	AxisAlignedBox3 lbox = box;
1320	AxisAlignedBox3 rbox = box;
1321	lbox.SetMax(axis, (*ci).value);
1322	rbox.SetMin(axis, (*ci).value);
1323
1324	const float sum = objectsLeft * lbox.SurfaceArea() +
1325	objectsRight * rbox.SurfaceArea();
1326
1327	if (sum < minSum)
1328	{
1329	minSum = sum;
1330	position = (*ci).value;
1331
1332	objectsBack = objectsLeft;
1333	objectsFront = objectsRight;
1334	}
1335	}
1336	}
1337
1338	const float oldCost = (float)polys.size();
1339	const float newCost = mAxisAlignedCtDivCi + minSum / boxArea;
1340	const float ratio = newCost / oldCost;
1341
1342	#ifdef _DEBUG
1343	Debug << "====================" << endl;
1344	Debug << "costRatio=" << ratio << " pos=" << position<<" t=" << (position - minBox)/(maxBox - minBox)
1345	<< "\t o=(" << objectsBack << "," << objectsFront << ")" << endl;
1346	#endif
1347	return ratio;
1348	}
1349
1350	bool BspTree::SelectAxisAlignedPlane(Plane3 &plane,
1351	const PolygonContainer &polys) const
1352	{
1353	AxisAlignedBox3 box;
1354	box.Initialize();
1355
1356	// create bounding box of region
1357	box.Include(polys);
1358
1359	int objectsBack = 0, objectsFront = 0;
1360	int axis = 0;
1361	float costRatio = MAX_FLOAT;
1362	Vector3 position;
1363
1364	//-- area subdivision
1365	for (int i = 0; i < 3; ++ i)
1366	{
1367	float p = 0;
1368	float r = BestCostRatio(polys, box, i, p, objectsBack, objectsFront);
1369
1370	if (r < costRatio)
1371	{
1372	costRatio = r;
1373	axis = i;
1374	position = p;
1375	}
1376	}
1377
1378	if (costRatio >= mMaxCostRatio)
1379	return false;
1380
1381	Vector3 norm(0,0,0); norm[axis] = 1.0f;
1382	plane = Plane3(norm, position);
1383
1384	return true;
1385	}
1386
1387
1388	Plane3 BspTree::SelectPlane(BspLeaf *leaf, BspTraversalData &data)
1389	{
1390	if ((!mMaxPolyCandidates \|\| data.mPolygons->empty()) &&
1391	(!mMaxRayCandidates \|\| data.mRays->empty()))
1392	{
1393	Debug << "Warning: No autopartition polygon candidate available\n";
1394
1395	// return axis aligned split
1396	AxisAlignedBox3 box;
1397	box.Initialize();
1398
1399	// create bounding box of region
1400	box.Include(*data.mPolygons);
1401
1402	const int axis = box.Size().DrivingAxis();
1403	const Vector3 position = (box.Min()[axis] + box.Max()[axis]) * 0.5f;
1404
1405	Vector3 norm(0,0,0); norm[axis] = 1.0f;
1406	return Plane3(norm, position);
1407	}
1408
1409	if ((mSplitPlaneStrategy & AXIS_ALIGNED) &&
1410	((int)data.mPolygons->size() > mTermMinPolysForAxisAligned) &&
1411	((int)data.mRays->size() > mTermMinRaysForAxisAligned) &&
1412	((mTermMinObjectsForAxisAligned < 0) \|\|
1413	(Polygon3::ParentObjectsSize(*data.mPolygons) > mTermMinObjectsForAxisAligned)))
1414	{
1415	Plane3 plane;
1416	if (SelectAxisAlignedPlane(plane, *data.mPolygons))
1417	return plane;
1418	}
1419
1420	// simplest strategy: just take next polygon
1421	if (mSplitPlaneStrategy & RANDOM_POLYGON)
1422	{
1423	if (!data.mPolygons->empty())
1424	{
1425	Polygon3 *nextPoly =
1426	(*data.mPolygons)[(int)RandomValue(0, (Real)((int)data.mPolygons->size() - 1))];
1427	return nextPoly->GetSupportingPlane();
1428	}
1429	else
1430	{
1431	const int candidateIdx = (int)RandomValue(0, (Real)((int)data.mRays->size() - 1));
1432	BoundedRay bRay = (data.mRays)[candidateIdx];
1433
1434	Ray *ray = bRay->mRay;
1435
1436	const Vector3 minPt = ray->Extrap(bRay->mMinT);
1437	const Vector3 maxPt = ray->Extrap(bRay->mMaxT);
1438
1439	const Vector3 pt = (maxPt + minPt) * 0.5;
1440
1441	const Vector3 normal = ray->GetDir();
1442
1443	return Plane3(normal, pt);
1444	}
1445
1446	return Plane3();
1447	}
1448
1449	// use heuristics to find appropriate plane
1450	return SelectPlaneHeuristics(leaf, data);
1451	}
1452
1453
1454	Plane3 BspTree::ChooseCandidatePlane(const BoundedRayContainer &rays) const
1455	{
1456	const int candidateIdx = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1457	BoundedRay *bRay = rays[candidateIdx];
1458	Ray *ray = bRay->mRay;
1459
1460	const Vector3 minPt = ray->Extrap(bRay->mMinT);
1461	const Vector3 maxPt = ray->Extrap(bRay->mMaxT);
1462
1463	const Vector3 pt = (maxPt + minPt) * 0.5;
1464
1465	const Vector3 normal = ray->GetDir();
1466
1467	return Plane3(normal, pt);
1468	}
1469
1470	Plane3 BspTree::ChooseCandidatePlane2(const BoundedRayContainer &rays) const
1471	{
1472	Vector3 pt[3];
1473	int idx[3];
1474	int cmaxT = 0;
1475	int cminT = 0;
1476	bool chooseMin = false;
1477
1478	for (int j = 0; j < 3; j ++)
1479	{
1480	idx[j] = (int)RandomValue(0, Real((int)rays.size() * 2 - 1));
1481
1482	if (idx[j] >= (int)rays.size())
1483	{
1484	idx[j] -= (int)rays.size();
1485	chooseMin = (cminT < 2);
1486	}
1487	else
1488	chooseMin = (cmaxT < 2);
1489
1490	BoundedRay *bRay = rays[idx[j]];
1491	pt[j] = chooseMin ? bRay->mRay->Extrap(bRay->mMinT) :
1492	bRay->mRay->Extrap(bRay->mMaxT);
1493	}
1494
1495	return Plane3(pt[0], pt[1], pt[2]);
1496	}
1497
1498
1499	Plane3 BspTree::ChooseCandidatePlane3(const BoundedRayContainer &rays) const
1500	{
1501	Vector3 pt[3];
1502
1503	int idx1 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1504	int idx2 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1505
1506	// check if rays different
1507	if (idx1 == idx2)
1508	idx2 = (idx2 + 1) % (int)rays.size();
1509
1510	const BoundedRay *ray1 = rays[idx1];
1511	const BoundedRay *ray2 = rays[idx2];
1512
1513	// normal vector of the plane parallel to both lines
1514	const Vector3 norm =
1515	Normalize(CrossProd(ray1->mRay->GetDir(), ray2->mRay->GetDir()));
1516
1517	const Vector3 orig1 = ray1->mRay->Extrap(ray1->mMinT);
1518	const Vector3 orig2 = ray2->mRay->Extrap(ray2->mMinT);
1519
1520	// vector from line 1 to line 2
1521	const Vector3 vd = orig1 - orig2;
1522
1523	// project vector on normal to get distance
1524	const float dist = DotProd(vd, norm);
1525
1526	// point on plane lies halfway between the two planes
1527	const Vector3 planePt = orig1 + norm * dist * 0.5;
1528
1529	return Plane3(norm, planePt);
1530	}
1531
1532
1533	Plane3 BspTree::SelectPlaneHeuristics(BspLeaf *leaf, BspTraversalData &data)
1534	{
1535	float lowestCost = MAX_FLOAT;
1536	Plane3 bestPlane;
1537	// intermediate plane
1538	Plane3 plane;
1539
1540	const int limit = Min((int)data.mPolygons->size(), mMaxPolyCandidates);
1541	int maxIdx = (int)data.mPolygons->size();
1542
1543	for (int i = 0; i < limit; ++ i)
1544	{
1545	// assure that no index is taken twice
1546	const int candidateIdx = (int)RandomValue(0, (Real)(-- maxIdx));
1547
1548	Polygon3 poly = (data.mPolygons)[candidateIdx];
1549
1550	// swap candidate to the end to avoid testing same plane
1551	std::swap((data.mPolygons)[maxIdx], (data.mPolygons)[candidateIdx]);
1552	//Polygon3 poly = (data.mPolygons)[(int)RandomValue(0, (int)polys.size() - 1)];
1553
1554	// evaluate current candidate
1555	const float candidateCost =
1556	SplitPlaneCost(poly->GetSupportingPlane(), data);
1557
1558	if (candidateCost < lowestCost)
1559	{
1560	bestPlane = poly->GetSupportingPlane();
1561	lowestCost = candidateCost;
1562	}
1563	}
1564
1565	//-- choose candidate planes extracted from rays
1566	for (int i = 0; i < mMaxRayCandidates; ++ i)
1567	{
1568	plane = ChooseCandidatePlane3(*data.mRays);
1569	const float candidateCost = SplitPlaneCost(plane, data);
1570
1571	if (candidateCost < lowestCost)
1572	{
1573	bestPlane = plane;
1574	lowestCost = candidateCost;
1575	}
1576	}
1577
1578	#ifdef _DEBUG
1579	Debug << "plane lowest cost: " << lowestCost << endl;
1580	#endif
1581
1582	return bestPlane;
1583	}
1584
1585
1586	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1587	const PolygonContainer &polys) const
1588	{
1589	float val = 0;
1590
1591	float sumBalancedPolys = 0;
1592	float sumSplits = 0;
1593	float sumPolyArea = 0;
1594	float sumBalancedViewCells = 0;
1595	float sumBlockedRays = 0;
1596	float totalBlockedRays = 0;
1597	//float totalArea = 0;
1598	int totalViewCells = 0;
1599
1600	// need three unique ids for each type of view cell
1601	// for balanced view cells criterium
1602	ViewCell::NewMail();
1603	const int backId = ViewCell::sMailId;
1604	ViewCell::NewMail();
1605	const int frontId = ViewCell::sMailId;
1606	ViewCell::NewMail();
1607	const int frontAndBackId = ViewCell::sMailId;
1608
1609	bool useRand;
1610	int limit;
1611
1612	// choose test polyongs randomly if over threshold
1613	if ((int)polys.size() > mMaxTests)
1614	{
1615	useRand = true;
1616	limit = mMaxTests;
1617	}
1618	else
1619	{
1620	useRand = false;
1621	limit = (int)polys.size();
1622	}
1623
1624	for (int i = 0; i < limit; ++ i)
1625	{
1626	const int testIdx = useRand ? (int)RandomValue(0, (Real)(limit - 1)) : i;
1627
1628	Polygon3 *poly = polys[testIdx];
1629
1630	const int classification =
1631	poly->ClassifyPlane(candidatePlane, mEpsilon);
1632
1633	if (mSplitPlaneStrategy & BALANCED_POLYS)
1634	sumBalancedPolys += sBalancedPolysTable[classification];
1635
1636	if (mSplitPlaneStrategy & LEAST_SPLITS)
1637	sumSplits += sLeastPolySplitsTable[classification];
1638
1639	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
1640	{
1641	if (classification == Polygon3::COINCIDENT)
1642	sumPolyArea += poly->GetArea();
1643	//totalArea += area;
1644	}
1645
1646	if (mSplitPlaneStrategy & BLOCKED_RAYS)
1647	{
1648	const float blockedRays = (float)poly->mPiercingRays.size();
1649
1650	if (classification == Polygon3::COINCIDENT)
1651	sumBlockedRays += blockedRays;
1652
1653	totalBlockedRays += blockedRays;
1654	}
1655
1656	// assign view cells to back or front according to classificaion
1657	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
1658	{
1659	MeshInstance *viewCell = poly->mParent;
1660
1661	// assure that we only count a view cell
1662	// once for the front and once for the back side of the plane
1663	if (classification == Polygon3::FRONT_SIDE)
1664	{
1665	if ((viewCell->mMailbox != frontId) &&
1666	(viewCell->mMailbox != frontAndBackId))
1667	{
1668	sumBalancedViewCells += 1.0;
1669
1670	if (viewCell->mMailbox != backId)
1671	viewCell->mMailbox = frontId;
1672	else
1673	viewCell->mMailbox = frontAndBackId;
1674
1675	++ totalViewCells;
1676	}
1677	}
1678	else if (classification == Polygon3::BACK_SIDE)
1679	{
1680	if ((viewCell->mMailbox != backId) &&
1681	(viewCell->mMailbox != frontAndBackId))
1682	{
1683	sumBalancedViewCells -= 1.0;
1684
1685	if (viewCell->mMailbox != frontId)
1686	viewCell->mMailbox = backId;
1687	else
1688	viewCell->mMailbox = frontAndBackId;
1689
1690	++ totalViewCells;
1691	}
1692	}
1693	}
1694	}
1695
1696	const float polysSize = (float)polys.size() + Limits::Small;
1697
1698	// all values should be approx. between 0 and 1 so they can be combined
1699	// and scaled with the factors according to their importance
1700	if (mSplitPlaneStrategy & BALANCED_POLYS)
1701	val += mBalancedPolysFactor * fabs(sumBalancedPolys) / polysSize;
1702
1703	if (mSplitPlaneStrategy & LEAST_SPLITS)
1704	val += mLeastSplitsFactor * sumSplits / polysSize;
1705
1706	if (mSplitPlaneStrategy & LARGEST_POLY_AREA)
1707	// HACK: polys.size should be total area so scaling is between 0 and 1
1708	val += mLargestPolyAreaFactor * (float)polys.size() / sumPolyArea;
1709
1710	if (mSplitPlaneStrategy & BLOCKED_RAYS)
1711	if (totalBlockedRays != 0)
1712	val += mBlockedRaysFactor * (totalBlockedRays - sumBlockedRays) / totalBlockedRays;
1713
1714	if (mSplitPlaneStrategy & BALANCED_VIEW_CELLS)
1715	val += mBalancedViewCellsFactor * fabs(sumBalancedViewCells) /
1716	((float)totalViewCells + Limits::Small);
1717
1718	return val;
1719	}
1720
1721
1722	inline void BspTree::GenerateUniqueIdsForPvs()
1723	{
1724	Intersectable::NewMail(); sBackId = Intersectable::sMailId;
1725	Intersectable::NewMail(); sFrontId = Intersectable::sMailId;
1726	Intersectable::NewMail(); sFrontAndBackId = Intersectable::sMailId;
1727	}
1728
1729
1730	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1731	const BoundedRayContainer &rays,
1732	const int pvs,
1733	const float probability,
1734	const BspNodeGeometry &cell) const
1735	{
1736	float val = 0;
1737
1738	float sumBalancedRays = 0;
1739	float sumRaySplits = 0;
1740
1741	int frontPvs = 0;
1742	int backPvs = 0;
1743
1744	// probability that view point lies in child
1745	float pOverall = 0;
1746	float pFront = 0;
1747	float pBack = 0;
1748
1749	const bool pvsUseLen = false;
1750
1751
1752	if (mSplitPlaneStrategy & PVS)
1753	{
1754	// create unique ids for pvs heuristics
1755	GenerateUniqueIdsForPvs();
1756
1757	// construct child geometry with regard to the candidate split plane
1758	BspNodeGeometry geomFront;
1759	BspNodeGeometry geomBack;
1760
1761	const bool splitSuccessFull =
1762	cell.SplitGeometry(geomFront,
1763	geomBack,
1764	candidatePlane,
1765	mBbox,
1766	mEpsilon);
1767
1768	if (mUseAreaForPvs)
1769	{
1770	pFront = geomFront.GetArea();
1771	pBack = geomBack.GetArea();
1772	}
1773	else
1774	{
1775	pFront = geomFront.GetVolume();
1776	pBack = pOverall - pFront;
1777	}
1778
1779
1780	// give penalty to unbalanced split
1781	if (1 &&
1782	(!splitSuccessFull \|\| (pFront <= 0) \|\| (pBack <= 0) \|\|
1783	!geomFront.Valid() \|\| !geomBack.Valid()))
1784	{
1785	//Debug << "error f: " << pFront << " b: " << pBack << endl;
1786	return 99999.9f;
1787	}
1788
1789	pOverall = probability;
1790	}
1791
1792	bool useRand;
1793	int limit;
1794
1795	// choose test polyongs randomly if over threshold
1796	if ((int)rays.size() > mMaxTests)
1797	{
1798	useRand = true;
1799	limit = mMaxTests;
1800	}
1801	else
1802	{
1803	useRand = false;
1804	limit = (int)rays.size();
1805	}
1806
1807	for (int i = 0; i < limit; ++ i)
1808	{
1809	const int testIdx = useRand ? (int)RandomValue(0, (Real)(limit - 1)) : i;
1810
1811	BoundedRay *bRay = rays[testIdx];
1812
1813	Ray *ray = bRay->mRay;
1814	const float minT = bRay->mMinT;
1815	const float maxT = bRay->mMaxT;
1816
1817	Vector3 entP, extP;
1818
1819	const int cf =
1820	ray->ClassifyPlane(candidatePlane, minT, maxT, entP, extP);
1821
1822	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
1823	{
1824	sumBalancedRays += sBalancedRaysTable[cf];
1825	}
1826
1827	if (mSplitPlaneStrategy & BALANCED_RAYS)
1828	{
1829	sumRaySplits += sLeastRaySplitsTable[cf];
1830	}
1831
1832	if (mSplitPlaneStrategy & PVS)
1833	{
1834	// in case the ray intersects an object
1835	// assure that we only count the object
1836	// once for the front and once for the back side of the plane
1837
1838	// add the termination object
1839	if (!ray->intersections.empty())
1840	AddObjToPvs(ray->intersections[0].mObject, cf, frontPvs, backPvs);
1841
1842	// add the source object
1843	AddObjToPvs(ray->sourceObject.mObject, cf, frontPvs, backPvs);
1844	}
1845	}
1846
1847	const float raysSize = (float)rays.size() + Limits::Small;
1848
1849	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
1850	val += mLeastRaySplitsFactor * sumRaySplits / raysSize;
1851
1852	if (mSplitPlaneStrategy & BALANCED_RAYS)
1853	val += mBalancedRaysFactor * fabs(sumBalancedRays) / raysSize;
1854
1855	const float denom = pOverall * (float)pvs + Limits::Small;
1856
1857	if (mSplitPlaneStrategy & PVS)
1858	{
1859	val += mPvsFactor * (frontPvs * pFront + (backPvs * pBack)) / denom;
1860	}
1861
1862
1863	#ifdef _DEBUG
1864	Debug << "totalpvs: " << pvs << " ptotal: " << pOverall
1865	<< " frontpvs: " << frontPvs << " pFront: " << pFront
1866	<< " backpvs: " << backPvs << " pBack: " << pBack << endl << endl;
1867	#endif
1868
1869	return val;
1870	}
1871
1872	void BspTree::AddObjToPvs(Intersectable *obj,
1873	const int cf,
1874	int &frontPvs,
1875	int &backPvs) const
1876	{
1877	if (!obj)
1878	return;
1879	// TODO: does this really belong to no pvs?
1880	//if (cf == Ray::COINCIDENT) return;
1881
1882	// object belongs to both PVS
1883	const bool bothSides = (cf == Ray::FRONT_BACK) \|\|
1884	(cf == Ray::BACK_FRONT) \|\|
1885	(cf == Ray::COINCIDENT);
1886
1887	if ((cf == Ray::FRONT) \|\| bothSides)
1888	{
1889	if ((obj->mMailbox != sFrontId) &&
1890	(obj->mMailbox != sFrontAndBackId))
1891	{
1892	++ frontPvs;
1893
1894	if (obj->mMailbox == sBackId)
1895	obj->mMailbox = sFrontAndBackId;
1896	else
1897	obj->mMailbox = sFrontId;
1898	}
1899	}
1900
1901	if ((cf == Ray::BACK) \|\| bothSides)
1902	{
1903	if ((obj->mMailbox != sBackId) &&
1904	(obj->mMailbox != sFrontAndBackId))
1905	{
1906	++ backPvs;
1907
1908	if (obj->mMailbox == sFrontId)
1909	obj->mMailbox = sFrontAndBackId;
1910	else
1911	obj->mMailbox = sBackId;
1912	}
1913	}
1914	}
1915
1916
1917	float BspTree::SplitPlaneCost(const Plane3 &candidatePlane,
1918	BspTraversalData &data) const
1919	{
1920	float val = 0;
1921
1922	if (mSplitPlaneStrategy & VERTICAL_AXIS)
1923	{
1924	Vector3 tinyAxis(0,0,0); tinyAxis[mBbox.Size().TinyAxis()] = 1.0f;
1925	// we put a penalty on the dot product between the "tiny" vertical axis
1926	// and the split plane axis
1927	val += mVerticalSplitsFactor *
1928	fabs(DotProd(candidatePlane.mNormal, tinyAxis));
1929	}
1930
1931	// the following criteria loop over all polygons to find the cost value
1932	if ((mSplitPlaneStrategy & BALANCED_POLYS) \|\|
1933	(mSplitPlaneStrategy & LEAST_SPLITS) \|\|
1934	(mSplitPlaneStrategy & LARGEST_POLY_AREA) \|\|
1935	(mSplitPlaneStrategy & BALANCED_VIEW_CELLS) \|\|
1936	(mSplitPlaneStrategy & BLOCKED_RAYS))
1937	{
1938	val += SplitPlaneCost(candidatePlane, *data.mPolygons);
1939	}
1940
1941	// the following criteria loop over all rays to find the cost value
1942	if ((mSplitPlaneStrategy & BALANCED_RAYS) \|\|
1943	(mSplitPlaneStrategy & LEAST_RAY_SPLITS) \|\|
1944	(mSplitPlaneStrategy & PVS))
1945	{
1946	val += SplitPlaneCost(candidatePlane, *data.mRays, data.mPvs,
1947	data.mProbability, *data.mGeometry);
1948	}
1949
1950	// return linear combination of the sums
1951	return val;
1952	}
1953
1954	void BspTree::CollectLeaves(vector<BspLeaf *> &leaves) const
1955	{
1956	stack<BspNode *> nodeStack;
1957	nodeStack.push(mRoot);
1958
1959	while (!nodeStack.empty())
1960	{
1961	BspNode *node = nodeStack.top();
1962
1963	nodeStack.pop();
1964
1965	if (node->IsLeaf())
1966	{
1967	BspLeaf leaf = (BspLeaf )node;
1968	leaves.push_back(leaf);
1969	}
1970	else
1971	{
1972	BspInterior interior = dynamic_cast<BspInterior >(node);
1973
1974	nodeStack.push(interior->GetBack());
1975	nodeStack.push(interior->GetFront());
1976	}
1977	}
1978	}
1979
1980
1981	AxisAlignedBox3 BspTree::GetBoundingBox() const
1982	{
1983	return mBbox;
1984	}
1985
1986
1987	void BspTree::EvaluateLeafStats(const BspTraversalData &data)
1988	{
1989	// the node became a leaf -> evaluate stats for leafs
1990	BspLeaf leaf = dynamic_cast<BspLeaf >(data.mNode);
1991
1992	// store maximal and minimal depth
1993	if (data.mDepth > mStat.maxDepth)
1994	mStat.maxDepth = data.mDepth;
1995
1996	if (data.mDepth < mStat.minDepth)
1997	mStat.minDepth = data.mDepth;
1998
1999	// accumulate depth to compute average depth
2000	mStat.accumDepth += data.mDepth;
2001	// accumulate rays to compute rays / leaf
2002	mStat.accumRays += (int)data.mRays->size();
2003
2004	if (data.mDepth >= mTermMaxDepth)
2005	++ mStat.maxDepthNodes;
2006
2007	if (data.mPvs < mTermMinPvs)
2008	++ mStat.minPvsNodes;
2009
2010	if ((int)data.mRays->size() < mTermMinRays)
2011	++ mStat.minRaysNodes;
2012
2013	if (data.GetAvgRayContribution() > mTermMaxRayContribution)
2014	++ mStat.maxRayContribNodes;
2015
2016	if (data.mProbability <= mTermMinProbability)
2017	++ mStat.minProbabilityNodes;
2018
2019	#ifdef _DEBUG
2020	Debug << "BSP stats: "
2021	<< "Depth: " << data.mDepth << " (max: " << mTermMaxDepth << "), "
2022	<< "PVS: " << data.mPvs << " (min: " << mTermMinPvs << "), "
2023	<< "Probability: " << data.mProbability << " (min: " << mTermMinProbability << "), "
2024	<< "#polygons: " << (int)data.mPolygons->size() << " (max: " << mTermMinPolys << "), "
2025	<< "#rays: " << (int)data.mRays->size() << " (max: " << mTermMinRays << "), "
2026	<< "#pvs: " << leaf->GetViewCell()->GetPvs().CountObjectsInPvs() << "=, "
2027	<< "#avg ray contrib (pvs): " << (float)data.mPvs / (float)data.mRays->size() << endl;
2028	#endif
2029	}
2030
2031
2032	int BspTree::_CastRay(Ray &ray)
2033	{
2034	int hits = 0;
2035
2036	stack<BspRayTraversalData> tStack;
2037
2038	float maxt, mint;
2039
2040	if (!mBbox.GetRaySegment(ray, mint, maxt))
2041	return 0;
2042
2043	ViewCell::NewMail();
2044
2045	Vector3 entp = ray.Extrap(mint);
2046	Vector3 extp = ray.Extrap(maxt);
2047
2048	BspNode *node = mRoot;
2049	BspNode *farChild = NULL;
2050
2051	while (1)
2052	{
2053	if (!node->IsLeaf())
2054	{
2055	BspInterior in = dynamic_cast<BspInterior >(node);
2056
2057	Plane3 splitPlane = in->GetPlane();
2058	const int entSide = splitPlane.Side(entp);
2059	const int extSide = splitPlane.Side(extp);
2060
2061	if (entSide < 0)
2062	{
2063	node = in->GetBack();
2064
2065	if(extSide <= 0) // plane does not split ray => no far child
2066	continue;
2067
2068	farChild = in->GetFront(); // plane splits ray
2069
2070	} else if (entSide > 0)
2071	{
2072	node = in->GetFront();
2073
2074	if (extSide >= 0) // plane does not split ray => no far child
2075	continue;
2076
2077	farChild = in->GetBack(); // plane splits ray
2078	}
2079	else // ray and plane are coincident
2080	{
2081	// WHAT TO DO IN THIS CASE ?
2082	//break;
2083	node = in->GetFront();
2084	continue;
2085	}
2086
2087	// push data for far child
2088	tStack.push(BspRayTraversalData(farChild, extp, maxt));
2089
2090	// find intersection of ray segment with plane
2091	float t;
2092	extp = splitPlane.FindIntersection(ray.GetLoc(), extp, &t);
2093	maxt *= t;
2094
2095	} else // reached leaf => intersection with view cell
2096	{
2097	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2098
2099	if (!leaf->mViewCell->Mailed())
2100	{
2101	//ray.bspIntersections.push_back(Ray::BspIntersection(maxt, leaf));
2102	leaf->mViewCell->Mail();
2103	++ hits;
2104	}
2105
2106	//-- fetch the next far child from the stack
2107	if (tStack.empty())
2108	break;
2109
2110	entp = extp;
2111	mint = maxt; // NOTE: need this?
2112
2113	if (ray.GetType() == Ray::LINE_SEGMENT && mint > 1.0f)
2114	break;
2115
2116	BspRayTraversalData &s = tStack.top();
2117
2118	node = s.mNode;
2119	extp = s.mExitPoint;
2120	maxt = s.mMaxT;
2121
2122	tStack.pop();
2123	}
2124	}
2125
2126	return hits;
2127	}
2128
2129
2130	int BspTree::CastLineSegment(const Vector3 &origin,
2131	const Vector3 &termination,
2132	ViewCellContainer &viewcells)
2133	{
2134	int hits = 0;
2135	stack<BspRayTraversalData> tStack;
2136
2137	float mint = 0.0f, maxt = 1.0f;
2138
2139	//ViewCell::NewMail();
2140
2141	Vector3 entp = origin;
2142	Vector3 extp = termination;
2143
2144	BspNode *node = mRoot;
2145	BspNode *farChild = NULL;
2146
2147
2148	const float thresh = 1 ? 1e-6f : 0.0f;
2149
2150	while (1)
2151	{
2152	if (!node->IsLeaf())
2153	{
2154	BspInterior in = dynamic_cast<BspInterior >(node);
2155
2156	Plane3 splitPlane = in->GetPlane();
2157
2158	const int entSide = splitPlane.Side(entp, thresh);
2159	const int extSide = splitPlane.Side(extp, thresh);
2160
2161	if (entSide < 0)
2162	{
2163	node = in->GetBack();
2164
2165	// plane does not split ray => no far child
2166	if (extSide <= 0)
2167	continue;
2168
2169	farChild = in->GetFront(); // plane splits ray
2170	}
2171	else if (entSide > 0)
2172	{
2173	node = in->GetFront();
2174
2175	if (extSide >= 0) // plane does not split ray => no far child
2176	continue;
2177
2178	farChild = in->GetBack(); // plane splits ray
2179	}
2180	else // one of the ray end points is on the plane
2181	{ // NOTE: what to do if ray is coincident with plane?
2182	if (extSide < 0)
2183	node = in->GetBack();
2184	else //if (extSide > 0)
2185	node = in->GetFront();
2186	//else break; // coincident => count no intersections
2187
2188	continue; // no far child
2189	}
2190
2191	// push data for far child
2192	tStack.push(BspRayTraversalData(farChild, extp, maxt));
2193
2194	// find intersection of ray segment with plane
2195	float t;
2196	extp = splitPlane.FindIntersection(origin, extp, &t);
2197	maxt *= t;
2198	}
2199	else
2200	{
2201	// reached leaf => intersection with view cell
2202	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2203
2204	if (!leaf->mViewCell->Mailed())
2205	{
2206	viewcells.push_back(leaf->mViewCell);
2207	leaf->mViewCell->Mail();
2208	++ hits;
2209	}
2210
2211	//-- fetch the next far child from the stack
2212	if (tStack.empty())
2213	break;
2214
2215	entp = extp;
2216	mint = maxt; // NOTE: need this?
2217
2218	BspRayTraversalData &s = tStack.top();
2219
2220	node = s.mNode;
2221	extp = s.mExitPoint;
2222	maxt = s.mMaxT;
2223
2224	tStack.pop();
2225	}
2226	}
2227
2228	return hits;
2229	}
2230
2231
2232	void BspTree::CollectViewCells(ViewCellContainer &viewCells) const
2233	{
2234	stack<BspNode *> nodeStack;
2235	nodeStack.push(mRoot);
2236
2237	ViewCell::NewMail();
2238
2239	while (!nodeStack.empty())
2240	{
2241	BspNode *node = nodeStack.top();
2242	nodeStack.pop();
2243
2244	if (node->IsLeaf())
2245	{
2246	ViewCellLeaf viewCell = dynamic_cast<BspLeaf >(node)->mViewCell;
2247
2248	if (!viewCell->Mailed())
2249	{
2250	viewCell->Mail();
2251	viewCells.push_back(viewCell);
2252	}
2253	}
2254	else
2255	{
2256	BspInterior interior = dynamic_cast<BspInterior >(node);
2257
2258	nodeStack.push(interior->GetFront());
2259	nodeStack.push(interior->GetBack());
2260	}
2261	}
2262	}
2263
2264
2265	BspTreeStatistics &BspTree::GetStat()
2266	{
2267	return mStat;
2268	}
2269
2270
2271	float BspTree::AccumulatedRayLength(BoundedRayContainer &rays) const
2272	{
2273	float len = 0;
2274
2275	BoundedRayContainer::const_iterator it, it_end = rays.end();
2276
2277	for (it = rays.begin(); it != it_end; ++ it)
2278	{
2279	len += SqrDistance((it)->mRay->Extrap((it)->mMinT),
2280	(it)->mRay->Extrap((it)->mMaxT));
2281	}
2282
2283	return len;
2284	}
2285
2286
2287	int BspTree::SplitRays(const Plane3 &plane,
2288	BoundedRayContainer &rays,
2289	BoundedRayContainer &frontRays,
2290	BoundedRayContainer &backRays)
2291	{
2292	int splits = 0;
2293
2294	while (!rays.empty())
2295	{
2296	BoundedRay *bRay = rays.back();
2297	Ray *ray = bRay->mRay;
2298	float minT = bRay->mMinT;
2299	float maxT = bRay->mMaxT;
2300
2301	rays.pop_back();
2302
2303	Vector3 entP, extP;
2304
2305	const int cf =
2306	ray->ClassifyPlane(plane, minT, maxT, entP, extP);
2307
2308	// set id to ray classification
2309	ray->SetId(cf);
2310
2311	switch (cf)
2312	{
2313	case Ray::COINCIDENT: // TODO: should really discard ray?
2314	frontRays.push_back(bRay);
2315	break;
2316	case Ray::BACK:
2317	backRays.push_back(bRay);
2318	break;
2319	case Ray::FRONT:
2320	frontRays.push_back(bRay);
2321	break;
2322	case Ray::FRONT_BACK:
2323	{
2324	// find intersection of ray segment with plane
2325	const float t = plane.FindT(ray->GetLoc(), extP);
2326
2327	const float newT = t * maxT;
2328
2329	frontRays.push_back(new BoundedRay(ray, minT, newT));
2330	backRays.push_back(new BoundedRay(ray, newT, maxT));
2331
2332	DEL_PTR(bRay);
2333	}
2334	break;
2335	case Ray::BACK_FRONT:
2336	{
2337	// find intersection of ray segment with plane
2338	const float t = plane.FindT(ray->GetLoc(), extP);
2339	const float newT = t * bRay->mMaxT;
2340
2341	backRays.push_back(new BoundedRay(ray, minT, newT));
2342	frontRays.push_back(new BoundedRay(ray, newT, maxT));
2343
2344	DEL_PTR(bRay);
2345
2346	++ splits;
2347	}
2348	break;
2349	default:
2350	Debug << "Should not come here 4" << endl;
2351	break;
2352	}
2353	}
2354
2355	return splits;
2356	}
2357
2358	void BspTree::ExtractHalfSpaces(BspNode *n, vector<Plane3> &halfSpaces) const
2359	{
2360	BspNode *lastNode;
2361
2362	do
2363	{
2364	lastNode = n;
2365
2366	// want to get planes defining geometry of this node => don't take
2367	// split plane of node itself
2368	n = n->GetParent();
2369
2370	if (n)
2371	{
2372	BspInterior interior = dynamic_cast<BspInterior >(n);
2373	Plane3 halfSpace = dynamic_cast<BspInterior *>(interior)->GetPlane();
2374
2375	if (interior->GetBack() != lastNode)
2376	halfSpace.ReverseOrientation();
2377
2378	halfSpaces.push_back(halfSpace);
2379	}
2380	}
2381	while (n);
2382	}
2383
2384
2385	void BspTree::ConstructGeometry(ViewCell *vc,
2386	BspNodeGeometry &vcGeom) const
2387	{
2388	// if false, cannot construct geometry for interior leaf
2389	if (!mViewCellsTree)
2390	return;
2391
2392	ViewCellContainer leaves;
2393	mViewCellsTree->CollectLeaves(vc, leaves);
2394
2395	ViewCellContainer::const_iterator it, it_end = leaves.end();
2396
2397	for (it = leaves.begin(); it != it_end; ++ it)
2398	{
2399	// per definition out of bounds cell has zero volume
2400	if (IsOutOfBounds(*it))
2401	continue;
2402
2403	BspViewCell bspVc = dynamic_cast<BspViewCell >(*it);
2404	vector<BspLeaf *>::const_iterator bit, bit_end = bspVc->mLeaves.end();
2405
2406	for (bit = bspVc->mLeaves.begin(); bit != bit_end; ++ bit)
2407	{
2408	BspLeaf l = bit;
2409	ConstructGeometry(l, vcGeom);
2410	}
2411	}
2412	}
2413
2414
2415	void BspTree::ConstructGeometry(BspNode *n,
2416	BspNodeGeometry &geom) const
2417	{
2418	vector<Plane3> halfSpaces;
2419	ExtractHalfSpaces(n, halfSpaces);
2420
2421	PolygonContainer candidatePolys;
2422	vector<Plane3> candidatePlanes;
2423
2424	vector<Plane3>::const_iterator pit, pit_end = halfSpaces.end();
2425
2426	// bounded planes are added to the polygons
2427	for (pit = halfSpaces.begin(); pit != pit_end; ++ pit)
2428	{
2429	Polygon3 p = GetBoundingBox().CrossSection(pit);
2430
2431	if (p->Valid(mEpsilon))
2432	{
2433	candidatePolys.push_back(p);
2434	candidatePlanes.push_back(*pit);
2435	}
2436	}
2437
2438	// add faces of bounding box (also could be faces of the cell)
2439	for (int i = 0; i < 6; ++ i)
2440	{
2441	VertexContainer vertices;
2442
2443	for (int j = 0; j < 4; ++ j)
2444	vertices.push_back(mBbox.GetFace(i).mVertices[j]);
2445
2446	Polygon3 *poly = new Polygon3(vertices);
2447
2448	candidatePolys.push_back(poly);
2449	candidatePlanes.push_back(poly->GetSupportingPlane());
2450	}
2451
2452	for (int i = 0; i < (int)candidatePolys.size(); ++ i)
2453	{
2454	// polygon is split by all other planes
2455	for (int j = 0; (j < (int)halfSpaces.size()) && candidatePolys[i]; ++ j)
2456	{
2457	if (i == j) // polygon and plane are coincident
2458	continue;
2459
2460	VertexContainer splitPts;
2461	Polygon3 frontPoly, backPoly;
2462
2463	const int cf =
2464	candidatePolys[i]->ClassifyPlane(halfSpaces[j],
2465	mEpsilon);
2466
2467	switch (cf)
2468	{
2469	case Polygon3::SPLIT:
2470	frontPoly = new Polygon3();
2471	backPoly = new Polygon3();
2472
2473	candidatePolys[i]->Split(halfSpaces[j],
2474	*frontPoly,
2475	*backPoly,
2476	mEpsilon);
2477
2478	DEL_PTR(candidatePolys[i]);
2479
2480	if (backPoly->Valid(mEpsilon))
2481	candidatePolys[i] = backPoly;
2482	else
2483	DEL_PTR(backPoly);
2484
2485	// outside, don't need this
2486	DEL_PTR(frontPoly);
2487	break;
2488	// polygon outside of halfspace
2489	case Polygon3::FRONT_SIDE:
2490	DEL_PTR(candidatePolys[i]);
2491	break;
2492	// just take polygon as it is
2493	case Polygon3::BACK_SIDE:
2494	case Polygon3::COINCIDENT:
2495	default:
2496	break;
2497	}
2498	}
2499
2500	if (candidatePolys[i])
2501	{
2502	geom.Add(candidatePolys[i], candidatePlanes[i]);
2503	}
2504	}
2505	}
2506
2507
2508	void BspTree::SetViewCellsManager(ViewCellsManager *vcm)
2509	{
2510	mViewCellsManager = vcm;
2511	}
2512
2513
2514	typedef pair<BspNode , BspNodeGeometry > bspNodePair;
2515
2516
2517	int BspTree::FindNeighbors(BspNode *n,
2518	vector<BspLeaf *> &neighbors,
2519	const bool onlyUnmailed) const
2520	{
2521	stack<bspNodePair> nodeStack;
2522
2523	BspNodeGeometry nodeGeom;
2524	ConstructGeometry(n, nodeGeom);
2525
2526	// split planes from the root to this node
2527	// needed to verify that we found neighbor leaf
2528	// TODO: really needed?
2529	vector<Plane3> halfSpaces;
2530	ExtractHalfSpaces(n, halfSpaces);
2531
2532
2533	BspNodeGeometry *rgeom = new BspNodeGeometry();
2534	ConstructGeometry(mRoot, *rgeom);
2535
2536	nodeStack.push(bspNodePair(mRoot, rgeom));
2537
2538	while (!nodeStack.empty())
2539	{
2540	BspNode *node = nodeStack.top().first;
2541	BspNodeGeometry *geom = nodeStack.top().second;
2542
2543	nodeStack.pop();
2544
2545	if (node->IsLeaf())
2546	{
2547	// test if this leaf is in valid view space
2548	if (node->TreeValid() &&
2549	(node != n) &&
2550	(!onlyUnmailed \|\| !node->Mailed()))
2551	{
2552	bool isAdjacent = true;
2553
2554	if (1)
2555	{
2556	// test all planes of current node if still adjacent
2557	for (int i = 0; (i < halfSpaces.size()) && isAdjacent; ++ i)
2558	{
2559	const int cf =
2560	Polygon3::ClassifyPlane(geom->GetPolys(),
2561	halfSpaces[i],
2562	mEpsilon);
2563
2564	if (cf == Polygon3::FRONT_SIDE)
2565	{
2566	isAdjacent = false;
2567	}
2568	}
2569	}
2570	else
2571	{
2572	// TODO: why is this wrong??
2573	// test all planes of current node if still adjacent
2574	for (int i = 0; (i < nodeGeom.Size()) && isAdjacent; ++ i)
2575	{
2576	Polygon3 *poly = nodeGeom.GetPolys()[i];
2577
2578	const int cf =
2579	Polygon3::ClassifyPlane(geom->GetPolys(),
2580	poly->GetSupportingPlane(),
2581	mEpsilon);
2582
2583	if (cf == Polygon3::FRONT_SIDE)
2584	{
2585	isAdjacent = false;
2586	}
2587	}
2588	}
2589	// neighbor was found
2590	if (isAdjacent)
2591	{
2592	neighbors.push_back(dynamic_cast<BspLeaf *>(node));
2593	}
2594	}
2595	}
2596	else
2597	{
2598	BspInterior interior = dynamic_cast<BspInterior >(node);
2599
2600	const int cf = Polygon3::ClassifyPlane(nodeGeom.GetPolys(),
2601	interior->GetPlane(),
2602	mEpsilon);
2603
2604	BspNode *front = interior->GetFront();
2605	BspNode *back = interior->GetBack();
2606
2607	BspNodeGeometry *fGeom = new BspNodeGeometry();
2608	BspNodeGeometry *bGeom = new BspNodeGeometry();
2609
2610	geom->SplitGeometry(*fGeom,
2611	*bGeom,
2612	interior->GetPlane(),
2613	mBbox,
2614	//0.0000001f);
2615	mEpsilon);
2616
2617	if (cf == Polygon3::BACK_SIDE)
2618	{
2619	nodeStack.push(bspNodePair(interior->GetBack(), bGeom));
2620	DEL_PTR(fGeom);
2621	}
2622	else
2623	{
2624	if (cf == Polygon3::FRONT_SIDE)
2625	{
2626	nodeStack.push(bspNodePair(interior->GetFront(), fGeom));
2627	DEL_PTR(bGeom);
2628	}
2629	else
2630	{ // random decision
2631	nodeStack.push(bspNodePair(front, fGeom));
2632	nodeStack.push(bspNodePair(back, bGeom));
2633	}
2634	}
2635	}
2636
2637	DEL_PTR(geom);
2638	}
2639
2640	return (int)neighbors.size();
2641	}
2642
2643
2644	BspLeaf *BspTree::GetRandomLeaf(const bool onlyUnmailed)
2645	{
2646	stack<BspNode *> nodeStack;
2647
2648	nodeStack.push(mRoot);
2649
2650	int mask = rand();
2651
2652	while (!nodeStack.empty())
2653	{
2654	BspNode *node = nodeStack.top();
2655	nodeStack.pop();
2656
2657	if (node->IsLeaf())
2658	{
2659	if ( (!onlyUnmailed \|\| !node->Mailed()) )
2660	return dynamic_cast<BspLeaf *>(node);
2661	}
2662	else
2663	{
2664	BspInterior interior = dynamic_cast<BspInterior >(node);
2665
2666	// random decision
2667	if (mask & 1)
2668	nodeStack.push(interior->GetBack());
2669	else
2670	nodeStack.push(interior->GetFront());
2671
2672	mask = mask >> 1;
2673	}
2674	}
2675
2676	return NULL;
2677	}
2678
2679
2680	void BspTree::AddToPvs(BspLeaf *leaf,
2681	const BoundedRayContainer &rays,
2682	int &sampleContributions,
2683	int &contributingSamples)
2684	{
2685	sampleContributions = 0;
2686	contributingSamples = 0;
2687
2688	BoundedRayContainer::const_iterator it, it_end = rays.end();
2689
2690	ViewCellLeaf *vc = leaf->GetViewCell();
2691
2692	// add contributions from samples to the PVS
2693	for (it = rays.begin(); it != it_end; ++ it)
2694	{
2695	int contribution = 0;
2696	Ray ray = (it)->mRay;
2697	float relContribution;
2698	if (!ray->intersections.empty())
2699	contribution += vc->GetPvs().AddSample(ray->intersections[0].mObject,
2700	1.0f,
2701	relContribution);
2702
2703	if (ray->sourceObject.mObject)
2704	contribution += vc->GetPvs().AddSample(ray->sourceObject.mObject,
2705	1.0f,
2706	relContribution);
2707
2708	if (contribution)
2709	{
2710	sampleContributions += contribution;
2711	++ contributingSamples;
2712	}
2713
2714	//if (ray->mFlags & Ray::STORE_BSP_INTERSECTIONS)
2715	// ray->bspIntersections.push_back(Ray::BspIntersection((*it)->mMinT, this));
2716	}
2717	}
2718
2719
2720	int BspTree::ComputePvsSize(const BoundedRayContainer &rays) const
2721	{
2722	int pvsSize = 0;
2723
2724	BoundedRayContainer::const_iterator rit, rit_end = rays.end();
2725
2726	Intersectable::NewMail();
2727
2728	for (rit = rays.begin(); rit != rays.end(); ++ rit)
2729	{
2730	Ray ray = (rit)->mRay;
2731
2732	if (!ray->intersections.empty())
2733	{
2734	if (!ray->intersections[0].mObject->Mailed())
2735	{
2736	ray->intersections[0].mObject->Mail();
2737	++ pvsSize;
2738	}
2739	}
2740	if (ray->sourceObject.mObject)
2741	{
2742	if (!ray->sourceObject.mObject->Mailed())
2743	{
2744	ray->sourceObject.mObject->Mail();
2745	++ pvsSize;
2746	}
2747	}
2748	}
2749
2750	return pvsSize;
2751	}
2752
2753
2754	float BspTree::GetEpsilon() const
2755	{
2756	return mEpsilon;
2757	}
2758
2759
2760	int BspTree::CollectMergeCandidates(const vector<BspLeaf *> leaves,
2761	vector<MergeCandidate> &candidates)
2762	{
2763	BspLeaf::NewMail();
2764
2765	vector<BspLeaf *>::const_iterator it, it_end = leaves.end();
2766
2767	int numCandidates = 0;
2768
2769	// find merge candidates and push them into queue
2770	for (it = leaves.begin(); it != it_end; ++ it)
2771	{
2772	BspLeaf leaf = it;
2773
2774	// the same leaves must not be part of two merge candidates
2775	leaf->Mail();
2776	vector<BspLeaf *> neighbors;
2777	FindNeighbors(leaf, neighbors, true);
2778
2779	vector<BspLeaf *>::const_iterator nit, nit_end = neighbors.end();
2780
2781	// TODO: test if at least one ray goes from one leaf to the other
2782	for (nit = neighbors.begin(); nit != nit_end; ++ nit)
2783	{
2784	if ((*nit)->GetViewCell() != leaf->GetViewCell())
2785	{
2786	MergeCandidate mc(leaf->GetViewCell(), (*nit)->GetViewCell());
2787	candidates.push_back(mc);
2788
2789	++ numCandidates;
2790	if ((numCandidates % 1000) == 0)
2791	{
2792	cout << "collected " << numCandidates << " merge candidates" << endl;
2793	}
2794	}
2795	}
2796	}
2797
2798	Debug << "merge queue: " << (int)candidates.size() << endl;
2799	Debug << "leaves in queue: " << numCandidates << endl;
2800
2801
2802	return (int)leaves.size();
2803	}
2804
2805
2806	int BspTree::CollectMergeCandidates(const VssRayContainer &rays,
2807	vector<MergeCandidate> &candidates)
2808	{
2809	ViewCell::NewMail();
2810	long startTime = GetTime();
2811
2812	map<BspLeaf , vector<BspLeaf> > neighborMap;
2813	ViewCellContainer::const_iterator iit;
2814
2815	int numLeaves = 0;
2816
2817	BspLeaf::NewMail();
2818
2819	for (int i = 0; i < (int)rays.size(); ++ i)
2820	{
2821	VssRay *ray = rays[i];
2822
2823	// traverse leaves stored in the rays and compare and
2824	// merge consecutive leaves (i.e., the neighbors in the tree)
2825	if (ray->mViewCells.size() < 2)
2826	continue;
2827
2828	iit = ray->mViewCells.begin();
2829	BspViewCell bspVc = dynamic_cast<BspViewCell >(*(iit ++));
2830	BspLeaf *leaf = bspVc->mLeaves[0];
2831
2832	// traverse intersections
2833	// consecutive leaves are neighbors => add them to queue
2834	for (; iit != ray->mViewCells.end(); ++ iit)
2835	{
2836	// next pair
2837	BspLeaf *prevLeaf = leaf;
2838	bspVc = dynamic_cast<BspViewCell >(iit);
2839	leaf = bspVc->mLeaves[0];
2840
2841	// view space not valid or same view cell
2842	if (!leaf->TreeValid() \|\| !prevLeaf->TreeValid() \|\|
2843	(leaf->GetViewCell() == prevLeaf->GetViewCell()))
2844	continue;
2845
2846	vector<BspLeaf *> &neighbors = neighborMap[leaf];
2847
2848	bool found = false;
2849
2850	// both leaves inserted in queue already =>
2851	// look if double pair already exists
2852	if (leaf->Mailed() && prevLeaf->Mailed())
2853	{
2854	vector<BspLeaf *>::const_iterator it, it_end = neighbors.end();
2855
2856	for (it = neighbors.begin(); !found && (it != it_end); ++ it)
2857	if (*it == prevLeaf)
2858	found = true; // already in queue
2859	}
2860
2861	if (!found)
2862	{
2863	// this pair is not in map yet
2864	// => insert into the neighbor map and the queue
2865	neighbors.push_back(prevLeaf);
2866	neighborMap[prevLeaf].push_back(leaf);
2867
2868	leaf->Mail();
2869	prevLeaf->Mail();
2870
2871	MergeCandidate mc(leaf->GetViewCell(), prevLeaf->GetViewCell());
2872
2873	candidates.push_back(mc);
2874
2875	if (((int)candidates.size() % 1000) == 0)
2876	{
2877	cout << "collected " << (int)candidates.size() << " merge candidates" << endl;
2878	}
2879	}
2880	}
2881	}
2882
2883	Debug << "neighbormap size: " << (int)neighborMap.size() << endl;
2884	Debug << "merge queue: " << (int)candidates.size() << endl;
2885	Debug << "leaves in queue: " << numLeaves << endl;
2886
2887	#if 0
2888	//////////
2889	//-- collect the leaves which haven't been found by ray casting
2890	cout << "finding additional merge candidates using geometry" << endl;
2891	vector<BspLeaf *> leaves;
2892	CollectLeaves(leaves, true);
2893	Debug << "found " << (int)leaves.size() << " new leaves" << endl << endl;
2894	CollectMergeCandidates(leaves, candidates);
2895	#endif
2896
2897	return numLeaves;
2898	}
2899
2900
2901
2902	/***************************************************************/
2903	/* BspNodeGeometry Implementation */
2904	/***************************************************************/
2905
2906
2907	BspNodeGeometry::BspNodeGeometry(const BspNodeGeometry &rhs)
2908	{
2909	mPolys.reserve(rhs.mPolys.size());
2910	mPlanes.reserve(rhs.mPolys.size());
2911
2912	PolygonContainer::const_iterator it, it_end = rhs.mPolys.end();
2913
2914	int i = 0;
2915
2916	for (it = rhs.mPolys.begin(); it != it_end; ++ it, ++i)
2917	{
2918	Polygon3 poly = it;
2919	Add(new Polygon3(*poly), rhs.mPlanes[i]);
2920	}
2921	}
2922
2923
2924	BspNodeGeometry& BspNodeGeometry::operator=(const BspNodeGeometry& g)
2925	{
2926	if (this == &g)
2927	return *this;
2928
2929	CLEAR_CONTAINER(mPolys);
2930
2931	mPolys.reserve(g.mPolys.size());
2932	mPlanes.reserve(g.mPolys.size());
2933
2934	PolygonContainer::const_iterator it, it_end = g.mPolys.end();
2935
2936	int i = 0;
2937
2938	for (it = g.mPolys.begin(); it != it_end; ++ it, ++ i)
2939	{
2940	Polygon3 poly = it;
2941	Add(new Polygon3(*poly), g.mPlanes[i]);
2942	}
2943
2944	return *this;
2945	}
2946
2947
2948	BspNodeGeometry::BspNodeGeometry(const PolygonContainer &polys)
2949	{
2950	mPolys = polys;
2951	mPlanes.reserve(polys.size());
2952
2953	PolygonContainer::const_iterator it, it_end = polys.end();
2954
2955	for (it = polys.begin(); it != it_end; ++ it)
2956	{
2957	Polygon3 poly = it;
2958	mPlanes.push_back(poly->GetSupportingPlane());
2959	}
2960	}
2961
2962
2963	BspNodeGeometry::~BspNodeGeometry()
2964	{
2965	CLEAR_CONTAINER(mPolys);
2966	}
2967
2968
2969	int BspNodeGeometry::Size() const
2970	{
2971	return (int)mPolys.size();
2972	}
2973
2974
2975	const PolygonContainer &BspNodeGeometry::GetPolys()
2976	{
2977	return mPolys;
2978	}
2979
2980
2981	void BspNodeGeometry::Add(Polygon3 *p, const Plane3 &plane)
2982	{
2983	mPolys.push_back(p);
2984	mPlanes.push_back(plane);
2985	}
2986
2987
2988	float BspNodeGeometry::GetArea() const
2989	{
2990	return Polygon3::GetArea(mPolys);
2991	}
2992
2993
2994	float BspNodeGeometry::GetVolume() const
2995	{
2996	//-- compute volume using tetrahedralization of the geometry
2997	// and adding the volume of the single tetrahedrons
2998	float volume = 0;
2999	const float f = 1.0f / 6.0f;
3000
3001	PolygonContainer::const_iterator pit, pit_end = mPolys.end();
3002
3003	// note: can take arbitrary point, e.g., the origin. However,
3004	// we rather take the center of mass to prevents precision errors
3005	const Vector3 center = CenterOfMass();
3006
3007	for (pit = mPolys.begin(); pit != pit_end; ++ pit)
3008	{
3009	Polygon3 poly = pit;
3010	const Vector3 v0 = poly->mVertices[0] - center;
3011
3012	for (int i = 1; i < (int)poly->mVertices.size() - 1; ++ i)
3013	{
3014	const Vector3 v1 = poly->mVertices[i] - center;
3015	const Vector3 v2 = poly->mVertices[i + 1] - center;
3016
3017	// more robust version using abs and the center of mass
3018	volume += fabs (f * (DotProd(v0, CrossProd(v1, v2))));
3019	}
3020	}
3021
3022	return volume;
3023	}
3024
3025
3026	void BspNodeGeometry::GetBoundingBox(AxisAlignedBox3 &box) const
3027	{
3028	box.Initialize();
3029	box.Include(mPolys);
3030	}
3031
3032
3033	int BspNodeGeometry::Side(const Plane3 &plane, const float eps) const
3034	{
3035	PolygonContainer::const_iterator it, it_end = mPolys.end();
3036
3037	bool onFrontSide = false;
3038	bool onBackSide = false;
3039
3040	for (it = mPolys.begin(); it != it_end; ++ it)
3041	{
3042	const int side = (*it)->Side(plane, eps);
3043
3044	if (side == -1)
3045	onBackSide = true;
3046	else if (side == 1)
3047	onFrontSide = true;
3048
3049	if ((side == 0) \|\| (onBackSide && onFrontSide))
3050	return 0;
3051	}
3052
3053	if (onFrontSide)
3054	return 1;
3055
3056	return -1;
3057	}
3058
3059
3060	int BspNodeGeometry::ComputeIntersection(const AxisAlignedBox3 &box) const
3061	{
3062	// 1: box does not intersect geometry
3063	// 0: box intersects geometry
3064	// -1: box contains geometry
3065
3066	AxisAlignedBox3 boundingBox;
3067	GetBoundingBox(boundingBox);
3068
3069	// no intersections with bounding box
3070	if (!Overlap(box, boundingBox))
3071	{
3072	return 1;
3073	}
3074
3075	// box cotains bounding box of geometry >=> contains geometry
3076	if (box.Includes(boundingBox))
3077	return -1;
3078
3079	int result = 0;
3080
3081	// test geometry planes for intersections
3082	vector<Plane3>::const_iterator it, it_end = mPlanes.end();
3083
3084	for (it = mPlanes.begin(); it != it_end; ++ it)
3085	{
3086	const int side = box.Side(*it);
3087
3088	// box does not intersects geometry
3089	if (side == 1)
3090	{
3091	return 1;
3092	}
3093	//if (side == 0) result = 0;
3094	}
3095
3096	return result;
3097	}
3098
3099
3100	Vector3 BspNodeGeometry::CenterOfMass() const
3101	{
3102	int n = 0;
3103
3104	Vector3 center(0,0,0);
3105
3106	PolygonContainer::const_iterator pit, pit_end = mPolys.end();
3107
3108	for (pit = mPolys.begin(); pit != pit_end; ++ pit)
3109	{
3110	Polygon3 poly = pit;
3111
3112	VertexContainer::const_iterator vit, vit_end = poly->mVertices.end();
3113
3114	for(vit = poly->mVertices.begin(); vit != vit_end; ++ vit)
3115	{
3116	center += *vit;
3117	++ n;
3118	}
3119	}
3120
3121	//Debug << "center: " << center << " new " << center / (float)n << endl;
3122
3123	return center / (float)n;
3124	}
3125
3126
3127	bool BspNodeGeometry::Valid() const
3128	{
3129	// geometry is degenerated
3130	if (mPolys.size() < 4)
3131	return false;
3132
3133	return true;
3134	}
3135
3136	void IncludeNodeGeomInMesh(const BspNodeGeometry &geom, Mesh &mesh)
3137	{
3138	// add single polygons to mesh
3139	PolygonContainer::const_iterator it, it_end = geom.mPolys.end();
3140
3141	for (it = geom.mPolys.begin(); it != geom.mPolys.end(); ++ it)
3142	{
3143	Polygon3 poly = (it);
3144	IncludePolyInMesh(*poly, mesh);
3145	}
3146	}
3147
3148
3149	bool BspNodeGeometry::SplitGeometry(BspNodeGeometry &front,
3150	BspNodeGeometry &back,
3151	const Plane3 &splitPlane,
3152	const AxisAlignedBox3 &box,
3153	const float epsilon) const
3154	{
3155	//-- trivial cases
3156	if (0)
3157	{
3158	const int cf = Side(splitPlane, epsilon);
3159
3160	if (cf == -1)
3161	{
3162	back = *this;
3163	return false;
3164	}
3165	else if (cf == 1)
3166	{
3167	front = *this;
3168	return false;
3169	}
3170	}
3171
3172	// get cross section of new polygon
3173	Polygon3 *planePoly = box.CrossSection(splitPlane);
3174
3175	// split polygon with all other polygons
3176	planePoly = SplitPolygon(planePoly, epsilon);
3177
3178	bool splitsGeom = (planePoly != NULL);
3179
3180	//-- new polygon splits all other polygons
3181	for (int i = 0; i < (int)mPolys.size()/* && planePoly*/; ++ i)
3182	{
3183	/// don't use epsilon here to get exact split planes
3184	const int cf =
3185	mPolys[i]->ClassifyPlane(splitPlane, epsilon);
3186
3187	switch (cf)
3188	{
3189	case Polygon3::SPLIT:
3190	{
3191	Polygon3 *poly = new Polygon3(mPolys[i]->mVertices);
3192
3193	Polygon3 *frontPoly = new Polygon3();
3194	Polygon3 *backPoly = new Polygon3();
3195
3196	poly->Split(splitPlane,
3197	*frontPoly,
3198	*backPoly,
3199	epsilon);
3200
3201	DEL_PTR(poly);
3202
3203	if (frontPoly->Valid(epsilon))
3204	{
3205	front.Add(frontPoly, mPlanes[i]);
3206	}
3207	else
3208	{
3209	//Debug << "no f! " << endl;
3210	DEL_PTR(frontPoly);
3211	}
3212
3213	if (backPoly->Valid(epsilon))
3214	{
3215	back.Add(backPoly, mPlanes[i]);
3216	}
3217	else
3218	{
3219	//Debug << "no b! " << endl;
3220	DEL_PTR(backPoly);
3221	}
3222	}
3223
3224	break;
3225	case Polygon3::BACK_SIDE:
3226	back.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3227	break;
3228	case Polygon3::FRONT_SIDE:
3229	front.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3230	break;
3231	// only put into back container (split should have no effect ...)
3232	case Polygon3::COINCIDENT:
3233	//Debug << "error should not come here" << endl;
3234	splitsGeom = false;
3235
3236	if (DotProd(mPlanes[i].mNormal, splitPlane.mNormal > 0))
3237	back.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3238	else
3239	front.Add(new Polygon3(mPolys[i]->mVertices), mPlanes[i]);
3240	break;
3241	default:
3242	break;
3243	}
3244	}
3245
3246	//-- finally add the new polygon to the child node geometries
3247	if (planePoly)
3248	{
3249	// add polygon with reverse orientation to front cell
3250	Plane3 reversePlane(splitPlane);
3251	reversePlane.ReverseOrientation();
3252
3253	// add polygon with normal pointing into positive half space to back cell
3254	back.Add(planePoly, splitPlane);
3255	//back.mPolys.push_back(planePoly);
3256
3257	Polygon3 *reversePoly = planePoly->CreateReversePolygon();
3258	front.Add(reversePoly, reversePlane);
3259	//Debug << "poly normal : " << reversePoly->GetSupportingPlane().mNormal << " split plane normal " << reversePlane.mNormal << endl;
3260	}
3261
3262
3263	return splitsGeom;
3264	}
3265
3266
3267	Polygon3 BspNodeGeometry::SplitPolygon(Polygon3 planePoly,
3268	const float epsilon) const
3269	{
3270	if (!planePoly->Valid(epsilon))
3271	{
3272	//Debug << "not valid!!" << endl;
3273	DEL_PTR(planePoly);
3274	}
3275	// polygon is split by all other planes
3276	for (int i = 0; (i < (int)mPolys.size()) && planePoly; ++ i)
3277	{
3278	//Plane3 plane = mPolys[i]->GetSupportingPlane();
3279	Plane3 plane = mPlanes[i];
3280
3281	/// don't use epsilon here to get exact split planes
3282	const int cf =
3283	planePoly->ClassifyPlane(plane, epsilon);
3284
3285	// split new polygon with all previous planes
3286	switch (cf)
3287	{
3288	case Polygon3::SPLIT:
3289	{
3290	Polygon3 *frontPoly = new Polygon3();
3291	Polygon3 *backPoly = new Polygon3();
3292
3293	planePoly->Split(plane,
3294	*frontPoly,
3295	*backPoly,
3296	epsilon);
3297
3298	// don't need anymore
3299	DEL_PTR(planePoly);
3300	DEL_PTR(frontPoly);
3301
3302	// back polygon is belonging to geometry
3303	if (backPoly->Valid(epsilon))
3304	planePoly = backPoly;
3305	else
3306	DEL_PTR(backPoly);
3307	}
3308	break;
3309	case Polygon3::FRONT_SIDE:
3310	DEL_PTR(planePoly);
3311	break;
3312	// polygon is taken as it is
3313	case Polygon3::BACK_SIDE:
3314	case Polygon3::COINCIDENT:
3315	default:
3316	break;
3317	}
3318	}
3319
3320	return planePoly;
3321	}
3322
3323
3324	ViewCell *BspTree::GetViewCell(const Vector3 &point)
3325	{
3326	if (mRoot == NULL)
3327	return NULL;
3328
3329	stack<BspNode *> nodeStack;
3330	nodeStack.push(mRoot);
3331
3332	ViewCellLeaf *viewcell = NULL;
3333
3334	while (!nodeStack.empty()) {
3335	BspNode *node = nodeStack.top();
3336	nodeStack.pop();
3337
3338	if (node->IsLeaf())
3339	{
3340	viewcell = dynamic_cast<BspLeaf *>(node)->mViewCell;
3341	break;
3342	}
3343	else
3344	{
3345
3346	BspInterior interior = dynamic_cast<BspInterior >(node);
3347
3348	// random decision
3349	if (interior->GetPlane().Side(point) < 0)
3350	{
3351	nodeStack.push(interior->GetBack());
3352	}
3353	else
3354	{
3355	nodeStack.push(interior->GetFront());
3356	}
3357	}
3358	}
3359
3360	return viewcell;
3361	}
3362
3363
3364	bool BspTree::Export(OUT_STREAM &stream)
3365	{
3366	ExportNode(mRoot, stream);
3367	return true;
3368	}
3369
3370
3371	void BspTree::ExportNode(BspNode *node, OUT_STREAM &stream)
3372	{
3373	if (node->IsLeaf())
3374	{
3375	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3376	ViewCell *viewCell = mViewCellsTree->GetActiveViewCell(leaf->GetViewCell());
3377
3378	const int id = viewCell->GetId();
3379
3380	stream << "<Leaf viewCellId=\"" << id << "\" />" << endl;
3381	}
3382	else
3383	{
3384	BspInterior interior = dynamic_cast<BspInterior >(node);
3385
3386	Plane3 plane = interior->GetPlane();
3387	stream << "<Interior plane=\"" << plane.mNormal.x << " "
3388	<< plane.mNormal.y << " " << plane.mNormal.z << " "
3389	<< plane.mD << "\">" << endl;
3390
3391	ExportNode(interior->GetBack(), stream);
3392	ExportNode(interior->GetFront(), stream);
3393
3394	stream << "</Interior>" << endl;
3395	}
3396	}
3397
3398
3399	}

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