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source: GTP/trunk/Lib/Vis/Preprocessing/src/VspBspTree.cpp @ 729

Revision 729, 90.3 KB checked in by mattausch, 18 years ago (diff)
added cost flexible render cost measurements

Line
1	#include <stack>
2	#include <time.h>
3	#include <iomanip>
4
5	#include "Plane3.h"
6	#include "VspBspTree.h"
7	#include "Mesh.h"
8	#include "common.h"
9	#include "ViewCell.h"
10	#include "Environment.h"
11	#include "Polygon3.h"
12	#include "Ray.h"
13	#include "AxisAlignedBox3.h"
14	#include "Exporter.h"
15	#include "Plane3.h"
16	#include "ViewCellBsp.h"
17	#include "ViewCellsManager.h"
18	#include "Beam.h"
19
20	#define USE_FIXEDPOINT_T 0
21
22
23	//-- static members
24
25
26	int VspBspTree::sFrontId = 0;
27	int VspBspTree::sBackId = 0;
28	int VspBspTree::sFrontAndBackId = 0;
29
30	typedef pair<BspNode , BspNodeGeometry > bspNodePair;
31
32
33	// pvs penalty can be different from pvs size
34	inline float EvalPvsPenalty(const int pvs,
35	const int lower,
36	const int upper)
37	{
38	// clamp to minmax values
39	if (pvs < lower)
40	return (float)lower;
41	if (pvs > upper)
42	return (float)upper;
43
44	return (float)pvs;
45	}
46
47
48
49
50	/******************************************************************************/
51	/* class VspBspTree implementation */
52	/******************************************************************************/
53
54
55	VspBspTree::VspBspTree():
56	mRoot(NULL),
57	mUseAreaForPvs(false),
58	mCostNormalizer(Limits::Small),
59	mViewCellsManager(NULL),
60	mOutOfBoundsCell(NULL),
61	mStoreRays(false),
62	mRenderCostWeight(0.5),
63	mUseRandomAxis(false),
64	mTimeStamp(1)
65	{
66	bool randomize = false;
67	environment->GetBoolValue("VspBspTree.Construction.randomize", randomize);
68	if (randomize)
69	Randomize(); // initialise random generator for heuristics
70
71	//-- termination criteria for autopartition
72	environment->GetIntValue("VspBspTree.Termination.maxDepth", mTermMaxDepth);
73	environment->GetIntValue("VspBspTree.Termination.minPvs", mTermMinPvs);
74	environment->GetIntValue("VspBspTree.Termination.minRays", mTermMinRays);
75	environment->GetFloatValue("VspBspTree.Termination.minProbability", mTermMinProbability);
76	environment->GetFloatValue("VspBspTree.Termination.maxRayContribution", mTermMaxRayContribution);
77	environment->GetFloatValue("VspBspTree.Termination.minAccRayLenght", mTermMinAccRayLength);
78	environment->GetFloatValue("VspBspTree.Termination.maxCostRatio", mTermMaxCostRatio);
79	environment->GetIntValue("VspBspTree.Termination.missTolerance", mTermMissTolerance);
80	environment->GetIntValue("VspBspTree.Termination.maxViewCells", mMaxViewCells);
81
82	//-- max cost ratio for early tree termination
83	environment->GetFloatValue("VspBspTree.Termination.maxCostRatio", mTermMaxCostRatio);
84
85	environment->GetFloatValue("VspBspTree.Termination.minGlobalCostRatio", mTermMinGlobalCostRatio);
86	environment->GetIntValue("VspBspTree.Termination.globalCostMissTolerance", mTermGlobalCostMissTolerance);
87
88	// HACK//mTermMinPolygons = 25;
89
90	//-- factors for bsp tree split plane heuristics
91	environment->GetFloatValue("VspBspTree.Factor.pvs", mPvsFactor);
92	environment->GetFloatValue("VspBspTree.Termination.ct_div_ci", mCtDivCi);
93
94
95	//-- partition criteria
96	environment->GetIntValue("VspBspTree.maxPolyCandidates", mMaxPolyCandidates);
97	environment->GetIntValue("VspBspTree.maxRayCandidates", mMaxRayCandidates);
98	environment->GetIntValue("VspBspTree.splitPlaneStrategy", mSplitPlaneStrategy);
99
100	environment->GetFloatValue("VspBspTree.Construction.epsilon", mEpsilon);
101	environment->GetIntValue("VspBspTree.maxTests", mMaxTests);
102
103	// if only the driving axis is used for axis aligned split
104	environment->GetBoolValue("VspBspTree.splitUseOnlyDrivingAxis", mOnlyDrivingAxis);
105
106	//-- termination criteria for axis aligned split
107	environment->GetFloatValue("VspBspTree.Termination.AxisAligned.maxRayContribution",
108	mTermMaxRayContriForAxisAligned);
109	environment->GetIntValue("VspBspTree.Termination.AxisAligned.minRays",
110	mTermMinRaysForAxisAligned);
111
112	//environment->GetFloatValue("VspBspTree.maxTotalMemory", mMaxTotalMemory);
113	environment->GetFloatValue("VspBspTree.maxStaticMemory", mMaxMemory);
114
115	environment->GetFloatValue("VspBspTree.Construction.renderCostWeight", mRenderCostWeight);
116	environment->GetBoolValue("VspBspTree.usePolygonSplitIfAvailable", mUsePolygonSplitIfAvailable);
117
118	environment->GetBoolValue("VspBspTree.useCostHeuristics", mUseCostHeuristics);
119	environment->GetBoolValue("VspBspTree.useSplitCostQueue", mUseSplitCostQueue);
120	environment->GetBoolValue("VspBspTree.simulateOctree", mSimulateOctree);
121	environment->GetBoolValue("VspBspTree.useRandomAxis", mUseRandomAxis);
122	environment->GetBoolValue("VspBspTree.useBreathFirstSplits", mBreathFirstSplits);
123
124	environment->GetBoolValue("ViewCells.PostProcess.emptyViewCellsMerge", mEmptyViewCellsMergeAllowed);
125
126	char subdivisionStatsLog[100];
127	environment->GetStringValue("VspBspTree.subdivisionStats", subdivisionStatsLog);
128	mSubdivisionStats.open(subdivisionStatsLog);
129
130	//-- debug output
131
132	Debug << "***** VSP BSP options ****** " << endl;
133	Debug << "max depth: " << mTermMaxDepth << endl;
134	Debug << "min PVS: " << mTermMinPvs << endl;
135	Debug << "min probabiliy: " << mTermMinProbability << endl;
136	Debug << "min rays: " << mTermMinRays << endl;
137	Debug << "max ray contri: " << mTermMaxRayContribution << endl;
138	Debug << "max cost ratio: " << mTermMaxCostRatio << endl;
139	Debug << "miss tolerance: " << mTermMissTolerance << endl;
140	Debug << "max view cells: " << mMaxViewCells << endl;
141	Debug << "max polygon candidates: " << mMaxPolyCandidates << endl;
142	//Debug << "max plane candidates: " << mMaxRayCandidates << endl;
143	Debug << "randomize: " << randomize << endl;
144
145	Debug << "using area for pvs: " << mUseAreaForPvs << endl;
146	Debug << "render cost weight: " << mRenderCostWeight << endl;
147	Debug << "min global cost ratio: " << mTermMinGlobalCostRatio << endl;
148	Debug << "global cost miss tolerance: " << mTermGlobalCostMissTolerance << endl;
149	Debug << "only driving axis: " << mOnlyDrivingAxis << endl;
150	Debug << "max memory: " << mMaxMemory << endl;
151	Debug << "use poly split if available: " << mUsePolygonSplitIfAvailable << endl;
152	Debug << "use cost heuristics: " << mUseCostHeuristics << endl;
153	Debug << "use split cost queue: " << mUseSplitCostQueue << endl;
154	Debug << "subdivision stats log: " << subdivisionStatsLog << endl;
155	Debug << "use random axis: " << mUseRandomAxis << endl;
156	Debug << "breath first splits: " << mBreathFirstSplits << endl;
157	Debug << "empty view cells merge: " << mEmptyViewCellsMergeAllowed << endl;
158
159	Debug << "octree: " << mSimulateOctree << endl;
160
161	Debug << "Split plane strategy: ";
162
163	if (mSplitPlaneStrategy & RANDOM_POLYGON)
164	{
165	Debug << "random polygon ";
166	}
167	if (mSplitPlaneStrategy & AXIS_ALIGNED)
168	{
169	Debug << "axis aligned ";
170	}
171	if (mSplitPlaneStrategy & LEAST_RAY_SPLITS)
172	{
173	mCostNormalizer += mLeastRaySplitsFactor;
174	Debug << "least ray splits ";
175	}
176	if (mSplitPlaneStrategy & BALANCED_RAYS)
177	{
178	mCostNormalizer += mBalancedRaysFactor;
179	Debug << "balanced rays ";
180	}
181	if (mSplitPlaneStrategy & PVS)
182	{
183	mCostNormalizer += mPvsFactor;
184	Debug << "pvs";
185	}
186
187
188	mSplitCandidates = new vector<SortableEntry>;
189
190	Debug << endl;
191	}
192
193
194	BspViewCell *VspBspTree::GetOutOfBoundsCell()
195	{
196	return mOutOfBoundsCell;
197	}
198
199
200	BspViewCell *VspBspTree::GetOrCreateOutOfBoundsCell()
201	{
202	if (!mOutOfBoundsCell)
203	{
204	mOutOfBoundsCell = new BspViewCell();
205	mOutOfBoundsCell->SetId(-1);
206	mOutOfBoundsCell->SetValid(false);
207	}
208
209	return mOutOfBoundsCell;
210	}
211
212
213	const BspTreeStatistics &VspBspTree::GetStatistics() const
214	{
215	return mBspStats;
216	}
217
218
219	VspBspTree::~VspBspTree()
220	{
221	DEL_PTR(mRoot);
222	DEL_PTR(mSplitCandidates);
223	}
224
225
226	int VspBspTree::AddMeshToPolygons(Mesh *mesh,
227	PolygonContainer &polys,
228	MeshInstance *parent)
229	{
230	FaceContainer::const_iterator fi;
231
232	// copy the face data to polygons
233	for (fi = mesh->mFaces.begin(); fi != mesh->mFaces.end(); ++ fi)
234	{
235	Polygon3 poly = new Polygon3((fi), mesh);
236
237	if (poly->Valid(mEpsilon))
238	{
239	poly->mParent = parent; // set parent intersectable
240	polys.push_back(poly);
241	}
242	else
243	DEL_PTR(poly);
244	}
245	return (int)mesh->mFaces.size();
246	}
247
248
249	int VspBspTree::AddToPolygonSoup(const ViewCellContainer &viewCells,
250	PolygonContainer &polys,
251	int maxObjects)
252	{
253	int limit = (maxObjects > 0) ?
254	Min((int)viewCells.size(), maxObjects) : (int)viewCells.size();
255
256	int polysSize = 0;
257
258	for (int i = 0; i < limit; ++ i)
259	{
260	if (viewCells[i]->GetMesh()) // copy the mesh data to polygons
261	{
262	mBox.Include(viewCells[i]->GetBox()); // add to BSP tree aabb
263	polysSize +=
264	AddMeshToPolygons(viewCells[i]->GetMesh(),
265	polys,
266	viewCells[i]);
267	}
268	}
269
270	return polysSize;
271	}
272
273
274	int VspBspTree::AddToPolygonSoup(const ObjectContainer &objects,
275	PolygonContainer &polys,
276	int maxObjects)
277	{
278	int limit = (maxObjects > 0) ?
279	Min((int)objects.size(), maxObjects) : (int)objects.size();
280
281	for (int i = 0; i < limit; ++i)
282	{
283	Intersectable object = objects[i];//it;
284	Mesh *mesh = NULL;
285
286	switch (object->Type()) // extract the meshes
287	{
288	case Intersectable::MESH_INSTANCE:
289	mesh = dynamic_cast<MeshInstance *>(object)->GetMesh();
290	break;
291	case Intersectable::VIEW_CELL:
292	mesh = dynamic_cast<ViewCell *>(object)->GetMesh();
293	break;
294	// TODO: handle transformed mesh instances
295	default:
296	Debug << "intersectable type not supported" << endl;
297	break;
298	}
299
300	if (mesh) // copy the mesh data to polygons
301	{
302	mBox.Include(object->GetBox()); // add to BSP tree aabb
303	AddMeshToPolygons(mesh, polys, NULL);
304	}
305	}
306
307	return (int)polys.size();
308	}
309
310
311	void VspBspTree::Construct(const VssRayContainer &sampleRays,
312	AxisAlignedBox3 *forcedBoundingBox)
313	{
314	mBspStats.nodes = 1;
315	mBox.Initialize(); // initialise BSP tree bounding box
316
317	if (forcedBoundingBox)
318	mBox = *forcedBoundingBox;
319
320	PolygonContainer polys;
321	RayInfoContainer *rays = new RayInfoContainer();
322
323	VssRayContainer::const_iterator rit, rit_end = sampleRays.end();
324
325	long startTime = GetTime();
326
327	cout << "Extracting polygons from rays ... ";
328
329	Intersectable::NewMail();
330
331	int numObj = 0;
332
333	//-- extract polygons intersected by the rays
334	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
335	{
336	VssRay ray = rit;
337
338	if ((mBox.IsInside(ray->mTermination) \|\| !forcedBoundingBox) &&
339	ray->mTerminationObject &&
340	!ray->mTerminationObject->Mailed())
341	{
342	ray->mTerminationObject->Mail();
343	MeshInstance obj = dynamic_cast<MeshInstance >(ray->mTerminationObject);
344	AddMeshToPolygons(obj->GetMesh(), polys, obj);
345	++ numObj;
346
347	//-- compute bounding box
348	if (!forcedBoundingBox)
349	mBox.Include(ray->mTermination);
350	}
351
352	if ((mBox.IsInside(ray->mOrigin) \|\| !forcedBoundingBox) &&
353	ray->mOriginObject &&
354	!ray->mOriginObject->Mailed())
355	{
356	ray->mOriginObject->Mail();
357	MeshInstance obj = dynamic_cast<MeshInstance >(ray->mOriginObject);
358	AddMeshToPolygons(obj->GetMesh(), polys, obj);
359	++ numObj;
360
361	//-- compute bounding box
362	if (!forcedBoundingBox)
363	mBox.Include(ray->mOrigin);
364	}
365	}
366
367	Debug << "maximal pvs (i.e., pvs still considered as valid) : "
368	<< mViewCellsManager->GetMaxPvsSize() << endl;
369
370	//-- store rays
371	for (rit = sampleRays.begin(); rit != rit_end; ++ rit)
372	{
373	VssRay ray = rit;
374
375	float minT, maxT;
376
377	static Ray hray;
378	hray.Init(*ray);
379
380	// TODO: not very efficient to implictly cast between rays types
381	if (mBox.GetRaySegment(hray, minT, maxT))
382	{
383	float len = ray->Length();
384
385	if (!len)
386	len = Limits::Small;
387
388	rays->push_back(RayInfo(ray, minT / len, maxT / len));
389	}
390	}
391
392	// normalize
393	if (mUseAreaForPvs)
394	mTermMinProbability *= mBox.SurfaceArea();
395	else
396	mTermMinProbability *= mBox.GetVolume();
397
398	// throw out unnecessary polygons
399	PreprocessPolygons(polys);
400
401	mBspStats.polys = (int)polys.size();
402	mGlobalCostMisses = 0;
403
404	cout << "finished" << endl;
405
406	Debug << "\nPolygon extraction: " << (int)polys.size() << " polys extracted from "
407	<< (int)sampleRays.size() << " rays in "
408	<< TimeDiff(startTime, GetTime())*1e-3 << " secs" << endl << endl;
409
410	// use split cost priority queue
411	if (mUseSplitCostQueue)
412	{
413	ConstructWithSplitQueue(polys, rays);
414	}
415	else
416	{
417	Construct(polys, rays);
418	}
419
420	// clean up polygons
421	CLEAR_CONTAINER(polys);
422	}
423
424
425	// TODO: return memory usage in MB
426	float VspBspTree::GetMemUsage() const
427	{
428	return (float)
429	(sizeof(VspBspTree) +
430	mBspStats.Leaves() * sizeof(BspLeaf) +
431	mCreatedViewCells * sizeof(BspViewCell) +
432	mBspStats.pvs * sizeof(ObjectPvsData) +
433	mBspStats.Interior() * sizeof(BspInterior) +
434	mBspStats.accumRays * sizeof(RayInfo)) / (1024.0f * 1024.0f);
435	}
436
437
438
439	void VspBspTree::Construct(const PolygonContainer &polys, RayInfoContainer *rays)
440	{
441	VspBspTraversalQueue tQueue;
442
443	mRoot = new BspLeaf();
444
445	// constrruct root node geometry
446	BspNodeGeometry *geom = new BspNodeGeometry();
447	ConstructGeometry(mRoot, *geom);
448
449	const float prop = mUseAreaForPvs ? geom->GetArea() : geom->GetVolume();
450
451	VspBspTraversalData tData(mRoot,
452	new PolygonContainer(polys),
453	0,
454	rays,
455	ComputePvsSize(*rays),
456	prop,
457	geom);
458
459	EvalPriority(tData);
460
461
462	// first node is kd node, i.e. an axis aligned box
463	if (1)
464	tData.mIsKdNode = true;
465	else
466	tData.mIsKdNode = false;
467
468	tQueue.push(tData);
469
470
471	mTotalCost = tData.mPvs * tData.mProbability / mBox.GetVolume();
472	mTotalPvsSize = tData.mPvs;
473
474	mSubdivisionStats
475	<< "#ViewCells\n1\n" << endl
476	<< "#RenderCostDecrease\n0\n" << endl
477	<< "#TotalRenderCost\n" << mTotalCost << endl
478	<< "#AvgRenderCost\n" << mTotalPvsSize << endl;
479
480	Debug << "total cost: " << mTotalCost << endl;
481
482
483	mBspStats.Start();
484	cout << "Constructing vsp bsp tree ... \n";
485
486	long startTime = GetTime();
487	int nLeaves = 500;
488	int nViewCells = 500;
489
490	// used for intermediate time measurements and progress
491	long interTime = GetTime();
492
493	mOutOfMemory = false;
494
495	mCreatedViewCells = 0;
496
497	while (!tQueue.empty())
498	{
499	tData = tQueue.top();
500	tQueue.pop();
501
502	if (0 && !mOutOfMemory)
503	{
504	float mem = GetMemUsage();
505
506	if (mem > mMaxMemory)
507	{
508	mOutOfMemory = true;
509	Debug << "memory limit reached: " << mem << endl;
510	}
511	}
512
513	// subdivide leaf node
514	BspNode *r = Subdivide(tQueue, tData);
515
516	if (r == mRoot)
517	Debug << "VSP BSP tree construction time spent at root: "
518	<< TimeDiff(startTime, GetTime())*1e-3 << "s" << endl;
519
520	if (mBspStats.Leaves() >= nLeaves)
521	{
522	nLeaves += 500;
523
524	cout << "leaves=" << mBspStats.Leaves() << endl;
525	Debug << "needed "
526	<< TimeDiff(interTime, GetTime())*1e-3
527	<< " secs to create 500 view cells" << endl;
528	interTime = GetTime();
529	}
530
531	if (mCreatedViewCells >= nViewCells)
532	{
533	nViewCells += 500;
534
535	cout << "generated " << mCreatedViewCells << " viewcells" << endl;
536	}
537	}
538
539	Debug << "Used Memory: " << GetMemUsage() << " MB" << endl << endl;
540	cout << "finished\n";
541
542	mBspStats.Stop();
543	}
544
545
546
547	void VspBspTree::ConstructWithSplitQueue(const PolygonContainer &polys,
548	RayInfoContainer *rays)
549	{
550	VspBspSplitQueue tQueue;
551
552	mRoot = new BspLeaf();
553
554	// constrruct root node geometry
555	BspNodeGeometry *geom = new BspNodeGeometry();
556	ConstructGeometry(mRoot, *geom);
557
558	const float prop = mUseAreaForPvs ? geom->GetArea() : geom->GetVolume();
559
560	VspBspTraversalData tData(mRoot,
561	new PolygonContainer(polys),
562	0,
563	rays,
564	ComputePvsSize(*rays),
565	prop,
566	geom);
567
568
569	// compute first split candidate
570	VspBspSplitCandidate splitCandidate;
571	EvalSplitCandidate(tData, splitCandidate);
572
573	tQueue.push(splitCandidate);
574
575	mTotalCost = tData.mPvs * tData.mProbability / mBox.GetVolume();
576	mTotalPvsSize = tData.mPvs;
577
578	mSubdivisionStats
579	<< "#ViewCells\n1\n" << endl
580	<< "#RenderCostDecrease\n0\n" << endl
581	<< "#dummy\n0\n" << endl
582	<< "#TotalRenderCost\n" << mTotalCost << endl
583	<< "#AvgRenderCost\n" << mTotalPvsSize << endl;
584
585	Debug << "total cost: " << mTotalCost << endl;
586
587
588	mBspStats.Start();
589	cout << "Constructing vsp bsp tree ... \n";
590
591	long startTime = GetTime();
592	int nLeaves = 500;
593	int nViewCells = 500;
594
595	// used for intermediate time measurements and progress
596	long interTime = GetTime();
597
598	mOutOfMemory = false;
599
600	mCreatedViewCells = 0;
601
602	while (!tQueue.empty())
603	{
604	splitCandidate = tQueue.top();
605	tQueue.pop();
606
607	// cost ratio of cost decrease / totalCost
608	float costRatio = splitCandidate.GetCost() / mTotalCost;
609
610	//Debug << "cost ratio: " << costRatio << endl;
611
612	if (costRatio < mTermMinGlobalCostRatio)
613	++ mGlobalCostMisses;
614
615	if (0 && !mOutOfMemory)
616	{
617	float mem = GetMemUsage();
618
619	if (mem > mMaxMemory)
620	{
621	mOutOfMemory = true;
622	Debug << "memory limit reached: " << mem << endl;
623	}
624	}
625
626	// subdivide leaf node
627	BspNode *r = Subdivide(tQueue, splitCandidate);
628
629	if (r == mRoot)
630	Debug << "VSP BSP tree construction time spent at root: "
631	<< TimeDiff(startTime, GetTime())*1e-3 << "s" << endl;
632
633	if (mBspStats.Leaves() >= nLeaves)
634	{
635	nLeaves += 500;
636
637	cout << "leaves=" << mBspStats.Leaves() << endl;
638	Debug << "needed "
639	<< TimeDiff(interTime, GetTime())*1e-3
640	<< " secs to create 500 view cells" << endl;
641	interTime = GetTime();
642	}
643
644	if (mCreatedViewCells == nViewCells)
645	{
646	nViewCells += 500;
647
648	cout << "generated " << mCreatedViewCells << " viewcells" << endl;
649	}
650	}
651
652	Debug << "Used Memory: " << GetMemUsage() << " MB" << endl << endl;
653	cout << "finished\n";
654
655	mBspStats.Stop();
656	}
657
658
659	bool VspBspTree::LocalTerminationCriteriaMet(const VspBspTraversalData &data) const
660	{
661	return
662	(((int)data.mRays->size() <= mTermMinRays) \|\|
663	(data.mPvs <= mTermMinPvs) \|\|
664	(data.mProbability <= mTermMinProbability) \|\|
665	(data.GetAvgRayContribution() > mTermMaxRayContribution) \|\|
666	(data.mDepth >= mTermMaxDepth));
667	}
668
669
670	bool VspBspTree::GlobalTerminationCriteriaMet(const VspBspTraversalData &data) const
671	{
672	return
673	(mOutOfMemory
674	\|\| (mBspStats.Leaves() >= mMaxViewCells)
675	\|\| (mGlobalCostMisses >= mTermGlobalCostMissTolerance)
676	);
677	}
678
679
680
681	BspNode *VspBspTree::Subdivide(VspBspTraversalQueue &tQueue,
682	VspBspTraversalData &tData)
683	{
684	BspNode *newNode = tData.mNode;
685
686	if (!LocalTerminationCriteriaMet(tData) && !GlobalTerminationCriteriaMet(tData))
687	{
688	PolygonContainer coincident;
689
690	VspBspTraversalData tFrontData;
691	VspBspTraversalData tBackData;
692
693	// create new interior node and two leaf nodes
694	// or return leaf as it is (if maxCostRatio missed)
695	int splitAxis;
696	bool splitFurther = true;
697	int maxCostMisses = tData.mMaxCostMisses;
698
699	Plane3 splitPlane;
700	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
701
702	// choose next split plane
703	if (!SelectPlane(splitPlane, leaf, tData, tFrontData, tBackData, splitAxis))
704	{
705	++ maxCostMisses;
706
707	if (maxCostMisses > mTermMissTolerance)
708	{
709	// terminate branch because of max cost
710	++ mBspStats.maxCostNodes;
711	splitFurther = false;
712	}
713	}
714
715	// if this a valid split => subdivide this node further
716	if (splitFurther) //-- continue subdivision
717	{
718	newNode = SubdivideNode(splitPlane, tData, tFrontData, tBackData, coincident);
719
720	if (splitAxis < 3)
721	++ mBspStats.splits[splitAxis];
722	else
723	++ mBspStats.polySplits;
724
725	tFrontData.mIsKdNode = tBackData.mIsKdNode = (tData.mIsKdNode && (splitAxis < 3));
726	tFrontData.mAxis = tBackData.mAxis = splitAxis;
727
728	// how often was max cost ratio missed in this branch?
729	tFrontData.mMaxCostMisses = maxCostMisses;
730	tBackData.mMaxCostMisses = maxCostMisses;
731
732	EvalPriority(tFrontData);
733	EvalPriority(tBackData);
734
735	// evaluate subdivision stats
736	if (1)
737	{
738	float cFront = (float)tFrontData.mPvs * tFrontData.mProbability;
739	float cBack = (float)tBackData.mPvs * tBackData.mProbability;
740	float cData = (float)tData.mPvs * tData.mProbability;;
741
742	float costDecr = (cFront + cBack - cData) / mBox.GetVolume();
743
744	mTotalCost += costDecr;
745	mTotalPvsSize += tFrontData.mPvs + tBackData.mPvs - tData.mPvs;
746
747	mSubdivisionStats
748	<< "#ViewCells\n" << mBspStats.Leaves() << endl
749	<< "#RenderCostDecrease\n" << -costDecr << endl
750	<< "#TotalRenderCost\n" << mTotalCost << endl
751	<< "#AvgRenderCost\n" << (float)mTotalPvsSize / (float)mBspStats.Leaves() << endl;
752	}
753
754	// push the children on the stack
755	tQueue.push(tFrontData);
756	tQueue.push(tBackData);
757
758	// delete old leaf node
759	DEL_PTR(tData.mNode);
760	}
761	}
762
763	//-- terminate traversal and create new view cell
764	if (newNode->IsLeaf())
765	{
766	BspLeaf leaf = dynamic_cast<BspLeaf >(newNode);
767	BspViewCell *viewCell = new BspViewCell();
768
769	leaf->SetViewCell(viewCell);
770
771	//-- update pvs
772	int conSamp = 0;
773	float sampCon = 0.0f;
774	AddToPvs(leaf, *tData.mRays, sampCon, conSamp);
775
776	mBspStats.contributingSamples += conSamp;
777	mBspStats.sampleContributions +=(int) sampCon;
778
779	//-- store additional info
780	if (mStoreRays)
781	{
782	RayInfoContainer::const_iterator it, it_end = tData.mRays->end();
783	for (it = tData.mRays->begin(); it != it_end; ++ it)
784	{
785	(*it).mRay->Ref();
786	leaf->mVssRays.push_back((*it).mRay);
787	}
788	}
789
790	// should I check here?
791	if (0 && !mViewCellsManager->CheckValidity(viewCell, 0, mViewCellsManager->GetMaxPvsSize()))
792	{
793	viewCell->SetValid(false);
794	leaf->SetTreeValid(false);
795	PropagateUpValidity(leaf);
796
797	++ mBspStats.invalidLeaves;
798	}
799
800	viewCell->mLeaf = leaf;
801
802	if (mUseAreaForPvs)
803	viewCell->SetArea(tData.mProbability);
804	else
805	viewCell->SetVolume(tData.mProbability);
806
807	leaf->mProbability = tData.mProbability;
808
809	EvaluateLeafStats(tData);
810	}
811
812	//-- cleanup
813	tData.Clear();
814
815	return newNode;
816	}
817
818	// subdivide using a split plane queue
819	BspNode *VspBspTree::Subdivide(VspBspSplitQueue &tQueue,
820	VspBspSplitCandidate &splitCandidate)
821	{
822	VspBspTraversalData &tData = splitCandidate.mParentData;
823
824	BspNode *newNode = tData.mNode;
825
826	if (!LocalTerminationCriteriaMet(tData) && !GlobalTerminationCriteriaMet(tData))
827	{
828	PolygonContainer coincident;
829
830	VspBspTraversalData tFrontData;
831	VspBspTraversalData tBackData;
832
833	//-- continue subdivision
834
835	// create new interior node and two leaf node
836	const Plane3 splitPlane = splitCandidate.mSplitPlane;
837
838	newNode = SubdivideNode(splitPlane, tData, tFrontData, tBackData, coincident);
839
840	const int splitAxis = splitCandidate.mSplitAxis;
841	const int maxCostMisses = splitCandidate.mMaxCostMisses;
842
843	if (splitAxis < 3)
844	++ mBspStats.splits[splitAxis];
845	else
846	++ mBspStats.polySplits;
847
848	tFrontData.mIsKdNode = tBackData.mIsKdNode = (tData.mIsKdNode && (splitAxis < 3));
849	tFrontData.mAxis = tBackData.mAxis = splitAxis;
850
851	// how often was max cost ratio missed in this branch?
852	tFrontData.mMaxCostMisses = maxCostMisses;
853	tBackData.mMaxCostMisses = maxCostMisses;
854
855
856	if (1)
857	{
858	float cFront = (float)tFrontData.mPvs * tFrontData.mProbability;
859	float cBack = (float)tBackData.mPvs * tBackData.mProbability;
860	float cData = (float)tData.mPvs * tData.mProbability;
861
862
863	float costDecr =
864	(cFront + cBack - cData) / mBox.GetVolume();
865
866	mTotalCost += costDecr;
867	mTotalPvsSize += tFrontData.mPvs + tBackData.mPvs - tData.mPvs;
868
869	mSubdivisionStats
870	<< "#ViewCells\n" << mBspStats.Leaves() << endl
871	<< "#RenderCostDecrease\n" << -costDecr << endl
872	<< "#dummy\n" << splitCandidate.GetCost() << endl
873	<< "#TotalRenderCost\n" << mTotalCost << endl
874	<< "#AvgRenderCost\n" << (float)mTotalPvsSize / (float)mBspStats.Leaves() << endl;
875	}
876
877
878	//-- push the new split candidates on the stack
879	VspBspSplitCandidate frontCandidate;
880	VspBspSplitCandidate backCandidate;
881
882	EvalSplitCandidate(tFrontData, frontCandidate);
883	EvalSplitCandidate(tBackData, backCandidate);
884
885	tQueue.push(frontCandidate);
886	tQueue.push(backCandidate);
887
888	// delete old leaf node
889	DEL_PTR(tData.mNode);
890	}
891
892
893	//-- terminate traversal and create new view cell
894	if (newNode->IsLeaf())
895	{
896	BspLeaf leaf = dynamic_cast<BspLeaf >(newNode);
897	BspViewCell *viewCell = new BspViewCell();
898
899	leaf->SetViewCell(viewCell);
900
901	//-- update pvs
902	int conSamp = 0;
903	float sampCon = 0.0f;
904	AddToPvs(leaf, *tData.mRays, sampCon, conSamp);
905
906	mBspStats.contributingSamples += conSamp;
907	mBspStats.sampleContributions +=(int) sampCon;
908
909	//-- store additional info
910	if (mStoreRays)
911	{
912	RayInfoContainer::const_iterator it, it_end = tData.mRays->end();
913	for (it = tData.mRays->begin(); it != it_end; ++ it)
914	{
915	(*it).mRay->Ref();
916	leaf->mVssRays.push_back((*it).mRay);
917	}
918	}
919
920	// should I check here?
921	viewCell->mLeaf = leaf;
922
923	if (mUseAreaForPvs)
924	viewCell->SetArea(tData.mProbability);
925	else
926	viewCell->SetVolume(tData.mProbability);
927
928	leaf->mProbability = tData.mProbability;
929
930	EvaluateLeafStats(tData);
931	}
932
933	//-- cleanup
934	tData.Clear();
935
936	return newNode;
937	}
938
939
940	void VspBspTree::EvalPriority(VspBspTraversalData &tData) const
941	{
942	tData.mPriority = mBreathFirstSplits ?
943	(float)-tData.mDepth : tData.mPvs * tData.mProbability;
944	//cout << "priority: " << tData.mPriority << endl;
945	}
946
947
948	void VspBspTree::EvalSplitCandidate(VspBspTraversalData &tData,
949	VspBspSplitCandidate &splitData)
950	{
951	VspBspTraversalData frontData;
952	VspBspTraversalData backData;
953
954	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
955
956	// compute locally best split plane
957	bool success = SelectPlane(splitData.mSplitPlane, leaf, tData,
958	frontData, backData, splitData.mSplitAxis);
959
960	// TODO: reuse
961	DEL_PTR(frontData.mGeometry);
962	DEL_PTR(backData.mGeometry);
963
964	// compute global decrease in render cost
965	splitData.mRenderCost = EvalRenderCostDecrease(splitData.mSplitPlane, tData);
966	splitData.mParentData = tData;
967	splitData.mMaxCostMisses = success ? tData.mMaxCostMisses : tData.mMaxCostMisses + 1;
968	}
969
970
971	BspInterior *VspBspTree::SubdivideNode(const Plane3 &splitPlane,
972	VspBspTraversalData &tData,
973	VspBspTraversalData &frontData,
974	VspBspTraversalData &backData,
975	PolygonContainer &coincident)
976	{
977	BspLeaf leaf = dynamic_cast<BspLeaf >(tData.mNode);
978
979	//-- the front and back traversal data is filled with the new values
980	frontData.mDepth = tData.mDepth + 1;
981	frontData.mPolygons = new PolygonContainer();
982	frontData.mRays = new RayInfoContainer();
983
984	backData.mDepth = tData.mDepth + 1;
985	backData.mPolygons = new PolygonContainer();
986	backData.mRays = new RayInfoContainer();
987
988
989	//-- subdivide rays
990	SplitRays(splitPlane,
991	*tData.mRays,
992	*frontData.mRays,
993	*backData.mRays);
994
995
996	// compute pvs
997	frontData.mPvs = ComputePvsSize(*frontData.mRays);
998	backData.mPvs = ComputePvsSize(*backData.mRays);
999
1000	// split front and back node geometry and compute area
1001
1002	// if geometry was not already computed
1003	if (!frontData.mGeometry && !backData.mGeometry)
1004	{
1005	frontData.mGeometry = new BspNodeGeometry();
1006	backData.mGeometry = new BspNodeGeometry();
1007
1008	tData.mGeometry->SplitGeometry(*frontData.mGeometry,
1009	*backData.mGeometry,
1010	splitPlane,
1011	mBox,
1012	//0.0f);
1013	mEpsilon);
1014
1015	if (mUseAreaForPvs)
1016	{
1017	frontData.mProbability = frontData.mGeometry->GetArea();
1018	backData.mProbability = backData.mGeometry->GetArea();
1019	}
1020	else
1021	{
1022	frontData.mProbability = frontData.mGeometry->GetVolume();
1023	backData.mProbability = tData.mProbability - frontData.mProbability;
1024
1025	if (frontData.mProbability < -0.00001)
1026	Debug << "fatal error f: " << frontData.mProbability << endl;
1027	if (backData.mProbability < -0.00001)
1028	Debug << "fatal error b: " << backData.mProbability << endl;
1029
1030	// clamp because of precision issues
1031	if (0)
1032	{
1033	if (frontData.mProbability < 0) frontData.mProbability = 0;
1034	if (backData.mProbability < 0) backData.mProbability = 0;
1035	}
1036	}
1037	}
1038
1039
1040	// subdivide polygons
1041	SplitPolygons(splitPlane,
1042	*tData.mPolygons,
1043	*frontData.mPolygons,
1044	*backData.mPolygons,
1045	coincident);
1046
1047
1048
1049	///////////////////////////////////////
1050	// subdivide further
1051
1052	// store maximal and minimal depth
1053	if (tData.mDepth > mBspStats.maxDepth)
1054	{
1055	Debug << "max depth increases to " << tData.mDepth << " at " << mBspStats.Leaves() << " leaves" << endl;
1056	mBspStats.maxDepth = tData.mDepth;
1057	}
1058
1059	mBspStats.nodes += 2;
1060
1061
1062	BspInterior *interior = new BspInterior(splitPlane);
1063
1064	#ifdef _DEBUG
1065	Debug << interior << endl;
1066	#endif
1067
1068
1069	//-- create front and back leaf
1070
1071	BspInterior *parent = leaf->GetParent();
1072
1073	// replace a link from node's parent
1074	if (parent)
1075	{
1076	parent->ReplaceChildLink(leaf, interior);
1077	interior->SetParent(parent);
1078	}
1079	else // new root
1080	{
1081	mRoot = interior;
1082	}
1083
1084	// and setup child links
1085	interior->SetupChildLinks(new BspLeaf(interior), new BspLeaf(interior));
1086
1087	frontData.mNode = interior->GetFront();
1088	backData.mNode = interior->GetBack();
1089
1090	interior->mTimeStamp = mTimeStamp ++;
1091
1092
1093	//DEL_PTR(leaf);
1094	return interior;
1095	}
1096
1097
1098	void VspBspTree::AddToPvs(BspLeaf *leaf,
1099	const RayInfoContainer &rays,
1100	float &sampleContributions,
1101	int &contributingSamples)
1102	{
1103	sampleContributions = 0;
1104	contributingSamples = 0;
1105
1106	RayInfoContainer::const_iterator it, it_end = rays.end();
1107
1108	ViewCell *vc = leaf->GetViewCell();
1109
1110	// add contributions from samples to the PVS
1111	for (it = rays.begin(); it != it_end; ++ it)
1112	{
1113	float sc = 0.0f;
1114	VssRay ray = (it).mRay;
1115	bool madeContrib = false;
1116	float contribution;
1117	if (ray->mTerminationObject) {
1118	if (vc->GetPvs().AddSample(ray->mTerminationObject, ray->mPdf, contribution))
1119	madeContrib = true;
1120	sc += contribution;
1121	}
1122
1123	if (ray->mOriginObject) {
1124	if (vc->GetPvs().AddSample(ray->mOriginObject, ray->mPdf, contribution))
1125	madeContrib = true;
1126	sc += contribution;
1127	}
1128
1129	sampleContributions += sc;
1130	if (madeContrib)
1131	++ contributingSamples;
1132
1133	//leaf->mVssRays.push_back(ray);
1134	}
1135	}
1136
1137
1138	void VspBspTree::SortSplitCandidates(const RayInfoContainer &rays,
1139	const int axis,
1140	float minBand,
1141	float maxBand)
1142	{
1143	mSplitCandidates->clear();
1144
1145	int requestedSize = 2 * (int)(rays.size());
1146	// creates a sorted split candidates array
1147	if (mSplitCandidates->capacity() > 500000 &&
1148	requestedSize < (int)(mSplitCandidates->capacity() / 10) )
1149	{
1150	delete mSplitCandidates;
1151	mSplitCandidates = new vector<SortableEntry>;
1152	}
1153
1154	mSplitCandidates->reserve(requestedSize);
1155
1156	float pos;
1157
1158	// float values => don't compare with exact values
1159	if (0)
1160	{
1161	minBand += Limits::Small;
1162	maxBand -= Limits::Small;
1163	}
1164
1165	// insert all queries
1166	for (RayInfoContainer::const_iterator ri = rays.begin(); ri < rays.end(); ++ ri)
1167	{
1168	const bool positive = (*ri).mRay->HasPosDir(axis);
1169
1170	pos = (*ri).ExtrapOrigin(axis);
1171	// clamp to min / max band
1172	if (0) ClipValue(pos, minBand, maxBand);
1173
1174	mSplitCandidates->push_back(SortableEntry(positive ? SortableEntry::ERayMin : SortableEntry::ERayMax,
1175	pos, (*ri).mRay));
1176
1177	pos = (*ri).ExtrapTermination(axis);
1178	// clamp to min / max band
1179	if (0) ClipValue(pos, minBand, maxBand);
1180
1181	mSplitCandidates->push_back(SortableEntry(positive ? SortableEntry::ERayMax : SortableEntry::ERayMin,
1182	pos, (*ri).mRay));
1183	}
1184
1185	stable_sort(mSplitCandidates->begin(), mSplitCandidates->end());
1186	}
1187
1188
1189	float VspBspTree::BestCostRatioHeuristics(const RayInfoContainer &rays,
1190	const AxisAlignedBox3 &box,
1191	const int pvsSize,
1192	const int axis,
1193	float &position)
1194	{
1195	const float minBox = box.Min(axis);
1196	const float maxBox = box.Max(axis);
1197	const float sizeBox = maxBox - minBox;
1198
1199	const float minBand = minBox + 0.1f * sizeBox;
1200	const float maxBand = minBox + 0.9f * sizeBox;
1201
1202	SortSplitCandidates(rays, axis, minBand, maxBand);
1203
1204	// go through the lists, count the number of objects left and right
1205	// and evaluate the following cost funcion:
1206	// C = ct_div_ci + (qlrl + qrrr)/queries
1207
1208	int pvsl = 0, pvsr = pvsSize;
1209
1210	int pvsBack = pvsl;
1211	int pvsFront = pvsr;
1212
1213	float sum = (float)pvsSize * sizeBox;
1214	float minSum = 1e20f;
1215
1216	// if no border can be found, take mid split
1217	position = minBox + 0.5f * sizeBox;
1218
1219	Intersectable::NewMail();
1220
1221	RayInfoContainer::const_iterator ri, ri_end = rays.end();
1222
1223	// set all object as belonging to the front pvs
1224	for(ri = rays.begin(); ri != ri_end; ++ ri)
1225	{
1226	Intersectable oObject = (ri).mRay->mOriginObject;
1227	Intersectable tObject = (ri).mRay->mTerminationObject;
1228
1229	if (oObject)
1230	{
1231	if (!oObject->Mailed())
1232	{
1233	oObject->Mail();
1234	oObject->mCounter = 1;
1235	}
1236	else
1237	{
1238	++ oObject->mCounter;
1239	}
1240	}
1241	if (tObject)
1242	{
1243	if (!tObject->Mailed())
1244	{
1245	tObject->Mail();
1246	tObject->mCounter = 1;
1247	}
1248	else
1249	{
1250	++ tObject->mCounter;
1251	}
1252	}
1253	}
1254
1255	Intersectable::NewMail();
1256
1257	vector<SortableEntry>::const_iterator ci, ci_end = mSplitCandidates->end();
1258
1259	for (ci = mSplitCandidates->begin(); ci < ci_end; ++ ci)
1260	{
1261	VssRay *ray;
1262	ray = (*ci).ray;
1263
1264	Intersectable *oObject = ray->mOriginObject;
1265	Intersectable *tObject = ray->mTerminationObject;
1266
1267
1268	switch ((*ci).type)
1269	{
1270	case SortableEntry::ERayMin:
1271	{
1272	if (oObject && !oObject->Mailed())
1273	{
1274	oObject->Mail();
1275	++ pvsl;
1276	}
1277	if (tObject && !tObject->Mailed())
1278	{
1279	tObject->Mail();
1280	++ pvsl;
1281	}
1282	break;
1283	}
1284	case SortableEntry::ERayMax:
1285	{
1286	if (oObject)
1287	{
1288	if (-- oObject->mCounter == 0)
1289	-- pvsr;
1290	}
1291
1292	if (tObject)
1293	{
1294	if (-- tObject->mCounter == 0)
1295	-- pvsr;
1296	}
1297
1298	break;
1299	}
1300	}
1301
1302	// Note: sufficient to compare size of bounding boxes of front and back side?
1303	if (((ci).value >= minBand) && ((ci).value <= maxBand))
1304	{
1305	sum = pvsl * ((ci).value - minBox) + pvsr (maxBox - (*ci).value);
1306
1307	// cout<<"pos="<<(*ci).value<<"\t q=("<<ql<<","<<qr<<")\t r=("<<rl<<","<<rr<<")"<<endl;
1308	// cout<<"cost= "<<sum<<endl;
1309
1310	if (sum < minSum)
1311	{
1312	minSum = sum;
1313	position = (*ci).value;
1314
1315	pvsBack = pvsl;
1316	pvsFront = pvsr;
1317	}
1318	}
1319	}
1320
1321	//Debug << "pos: " << position << " sizebox: " << sizeBox << " pvs: " << pvsSize << endl;
1322
1323	// -- compute cost
1324	const int lowerPvsLimit = mViewCellsManager->GetMinPvsSize();
1325	const int upperPvsLimit = mViewCellsManager->GetMaxPvsSize();
1326
1327	const float pOverall = sizeBox;
1328
1329	const float pBack = position - minBox;
1330	const float pFront = maxBox - position;
1331
1332	const float penaltyOld = EvalPvsPenalty(pvsSize, lowerPvsLimit, upperPvsLimit);
1333	const float penaltyFront = EvalPvsPenalty(pvsFront, lowerPvsLimit, upperPvsLimit);
1334	const float penaltyBack = EvalPvsPenalty(pvsBack, lowerPvsLimit, upperPvsLimit);
1335
1336	const float oldRenderCost = penaltyOld * pOverall;
1337	const float newRenderCost = penaltyFront * pFront + penaltyBack * pBack;
1338
1339	float ratio = mPvsFactor * newRenderCost / (oldRenderCost + Limits::Small);
1340
1341	//Debug << "costRatio=" << ratio << " pos=" << position << " t=" << (position - minBox) / (maxBox - minBox)
1342	// <<"\t q=(" << queriesBack << "," << queriesFront << ")\t r=(" << raysBack << "," << raysFront << ")" << endl;
1343
1344	return ratio;
1345	}
1346
1347
1348	float VspBspTree::SelectAxisAlignedPlane(Plane3 &plane,
1349	const VspBspTraversalData &tData,
1350	int &axis,
1351	BspNodeGeometry **frontGeom,
1352	BspNodeGeometry **backGeom,
1353	float &pFront,
1354	float &pBack,
1355	const bool isKdNode)
1356	{
1357	float nPosition[3];
1358	float nCostRatio[3];
1359	float nProbFront[3];
1360	float nProbBack[3];
1361
1362	BspNodeGeometry *nFrontGeom[3];
1363	BspNodeGeometry *nBackGeom[3];
1364
1365	for (int i = 0; i < 3; ++ i)
1366	{
1367	nFrontGeom[i] = NULL;
1368	nBackGeom[i] = NULL;
1369	}
1370
1371	int bestAxis = -1;
1372
1373	// create bounding box of node geometry
1374	AxisAlignedBox3 box;
1375
1376	//TODO: for kd split geometry already is box => only take minmax vertices
1377	if (1)
1378	{
1379	tData.mGeometry->GetBoundingBox(box);
1380	}
1381	else
1382	{
1383	box.Initialize();
1384	RayInfoContainer::const_iterator ri, ri_end = tData.mRays->end();
1385
1386	for(ri = tData.mRays->begin(); ri < ri_end; ++ ri)
1387	box.Include((*ri).ExtrapTermination());
1388	}
1389
1390	int sAxis = 0;
1391
1392	bool useSpecialAxis = mOnlyDrivingAxis \|\| mUseRandomAxis \|\| mSimulateOctree;
1393
1394	// use some kind of specialised fixed axis
1395	if (mOnlyDrivingAxis)
1396	sAxis = box.Size().DrivingAxis();
1397	else if (mUseRandomAxis)
1398	sAxis = Random(3);
1399	else if (mSimulateOctree)
1400	sAxis = (tData.mAxis + 1) % 3;
1401
1402	//Debug << "use special axis: " << useSpecialAxis << endl;
1403	//Debug << "axis: " << sAxis << " drivingaxis: " << box.Size().DrivingAxis();
1404
1405	for (axis = 0; axis < 3; ++ axis)
1406	{
1407	if (!useSpecialAxis \|\| (axis == sAxis))
1408	{
1409	if (!mUseCostHeuristics)
1410	{
1411	nPosition[axis] = (box.Min()[axis] + box.Max()[axis]) * 0.5f;
1412	Vector3 normal(0,0,0); normal[axis] = 1.0f;
1413
1414	// allows faster split because we have axis aligned kd tree boxes
1415	if (0 && isKdNode)
1416	{
1417	nCostRatio[axis] = EvalAxisAlignedSplitCost(tData,
1418	box,
1419	axis,
1420	nPosition[axis],
1421	nProbFront[axis],
1422	nProbBack[axis]);
1423
1424	Vector3 pos;
1425
1426	// create back geometry from box
1427	pos = box.Max(); pos[axis] = nPosition[axis];
1428	AxisAlignedBox3 bBox(box.Min(), pos);
1429	PolygonContainer fPolys;
1430	bBox.ExtractPolys(fPolys);
1431
1432	nBackGeom[axis] = new BspNodeGeometry(fPolys);
1433
1434	// create front geometry from box
1435	pos = box.Min(); pos[axis] = nPosition[axis];
1436	AxisAlignedBox3 fBox(pos, box.Max());
1437
1438	PolygonContainer bPolys;
1439	fBox.ExtractPolys(bPolys);
1440	nFrontGeom[axis] = new BspNodeGeometry(bPolys);
1441	}
1442	else
1443	{
1444	nFrontGeom[axis] = new BspNodeGeometry();
1445	nBackGeom[axis] = new BspNodeGeometry();
1446
1447	nCostRatio[axis] =
1448	EvalSplitPlaneCost(Plane3(normal, nPosition[axis]),
1449	tData, nFrontGeom[axis], nBackGeom[axis],
1450	nProbFront[axis], nProbBack[axis]);
1451	}
1452	}
1453	else
1454	{
1455	nCostRatio[axis] =
1456	BestCostRatioHeuristics(*tData.mRays,
1457	box,
1458	tData.mPvs,
1459	axis,
1460	nPosition[axis]);
1461	}
1462
1463	if (bestAxis == -1)
1464	{
1465	bestAxis = axis;
1466	}
1467	else if (nCostRatio[axis] < nCostRatio[bestAxis])
1468	{
1469	bestAxis = axis;
1470	}
1471
1472	}
1473	}
1474
1475	//-- assign values
1476	axis = bestAxis;
1477	pFront = nProbFront[bestAxis];
1478	pBack = nProbBack[bestAxis];
1479
1480	// assign best split nodes geometry
1481	*frontGeom = nFrontGeom[bestAxis];
1482	*backGeom = nBackGeom[bestAxis];
1483
1484	// and delete other geometry
1485	DEL_PTR(nFrontGeom[(bestAxis + 1) % 3]);
1486	DEL_PTR(nBackGeom[(bestAxis + 2) % 3]);
1487
1488	//-- split plane
1489	Vector3 normal(0,0,0); normal[bestAxis] = 1;
1490	plane = Plane3(normal, nPosition[bestAxis]);
1491
1492	return nCostRatio[bestAxis];
1493	}
1494
1495
1496	bool VspBspTree::SelectPlane(Plane3 &bestPlane,
1497	BspLeaf *leaf,
1498	VspBspTraversalData &data,
1499	VspBspTraversalData &frontData,
1500	VspBspTraversalData &backData,
1501	int &splitAxis)
1502	{
1503	// simplest strategy: just take next polygon
1504	if (mSplitPlaneStrategy & RANDOM_POLYGON)
1505	{
1506	if (!data.mPolygons->empty())
1507	{
1508	const int randIdx =
1509	(int)RandomValue(0, (Real)((int)data.mPolygons->size() - 1));
1510	Polygon3 nextPoly = (data.mPolygons)[randIdx];
1511
1512	bestPlane = nextPoly->GetSupportingPlane();
1513	return true;
1514	}
1515	}
1516
1517	//-- use heuristics to find appropriate plane
1518
1519	// intermediate plane
1520	Plane3 plane;
1521	float lowestCost = MAX_FLOAT;
1522
1523	// decides if the first few splits should be only axisAligned
1524	const bool onlyAxisAligned =
1525	(mSplitPlaneStrategy & AXIS_ALIGNED) &&
1526	((int)data.mRays->size() > mTermMinRaysForAxisAligned) &&
1527	((int)data.GetAvgRayContribution() < mTermMaxRayContriForAxisAligned);
1528
1529	const int limit = onlyAxisAligned ? 0 :
1530	Min((int)data.mPolygons->size(), mMaxPolyCandidates);
1531
1532	float candidateCost;
1533
1534	int maxIdx = (int)data.mPolygons->size();
1535
1536	for (int i = 0; i < limit; ++ i)
1537	{
1538	// the already taken candidates are stored behind maxIdx
1539	// => assure that no index is taken twice
1540	const int candidateIdx = (int)RandomValue(0, (Real)(-- maxIdx));
1541	Polygon3 poly = (data.mPolygons)[candidateIdx];
1542
1543	// swap candidate to the end to avoid testing same plane
1544	std::swap((data.mPolygons)[maxIdx], (data.mPolygons)[candidateIdx]);
1545	//Polygon3 poly = (data.mPolygons)[(int)RandomValue(0, (int)polys.size() - 1)];
1546
1547	// evaluate current candidate
1548	BspNodeGeometry fGeom, bGeom;
1549	float fArea, bArea;
1550	plane = poly->GetSupportingPlane();
1551	candidateCost = EvalSplitPlaneCost(plane, data, fGeom, bGeom, fArea, bArea);
1552
1553	if (candidateCost < lowestCost)
1554	{
1555	bestPlane = plane;
1556	lowestCost = candidateCost;
1557	}
1558	}
1559
1560	//-- evaluate axis aligned splits
1561	int axis;
1562	BspNodeGeometry fGeom, bGeom;
1563	float pFront, pBack;
1564
1565	candidateCost = 99999999.0f;
1566
1567	// option: axis aligned split only if no polygon available
1568	if (!mUsePolygonSplitIfAvailable \|\| data.mPolygons->empty())
1569	{
1570	candidateCost = SelectAxisAlignedPlane(plane,
1571	data,
1572	axis,
1573	&fGeom,
1574	&bGeom,
1575	pFront,
1576	pBack,
1577	data.mIsKdNode);
1578	}
1579
1580	splitAxis = 3;
1581
1582	if (candidateCost < lowestCost)
1583	{
1584	bestPlane = plane;
1585	lowestCost = candidateCost;
1586	splitAxis = axis;
1587
1588	// assign already computed values
1589	// we can do this because we always save the
1590	// computed values from the axis aligned splits
1591
1592	if (fGeom && bGeom)
1593	{
1594	frontData.mGeometry = fGeom;
1595	backData.mGeometry = bGeom;
1596
1597	frontData.mProbability = pFront;
1598	backData.mProbability = pBack;
1599	}
1600	}
1601	else
1602	{
1603	DEL_PTR(fGeom);
1604	DEL_PTR(bGeom);
1605	}
1606
1607
1608	// if (lowestCost > 10)
1609	// Debug << "warning!! lowest cost: " << lowestCost << endl;
1610
1611	#ifdef _DEBUG
1612	Debug << "plane lowest cost: " << lowestCost << endl;
1613	#endif
1614
1615	if (lowestCost > mTermMaxCostRatio)
1616	{
1617	return false;
1618	}
1619
1620	return true;
1621	}
1622
1623
1624	Plane3 VspBspTree::ChooseCandidatePlane(const RayInfoContainer &rays) const
1625	{
1626	const int candidateIdx = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1627
1628	const Vector3 minPt = rays[candidateIdx].ExtrapOrigin();
1629	const Vector3 maxPt = rays[candidateIdx].ExtrapTermination();
1630
1631	const Vector3 pt = (maxPt + minPt) * 0.5;
1632	const Vector3 normal = Normalize(rays[candidateIdx].mRay->GetDir());
1633
1634	return Plane3(normal, pt);
1635	}
1636
1637
1638	Plane3 VspBspTree::ChooseCandidatePlane2(const RayInfoContainer &rays) const
1639	{
1640	Vector3 pt[3];
1641
1642	int idx[3];
1643	int cmaxT = 0;
1644	int cminT = 0;
1645	bool chooseMin = false;
1646
1647	for (int j = 0; j < 3; ++ j)
1648	{
1649	idx[j] = (int)RandomValue(0, (Real)((int)rays.size() * 2 - 1));
1650
1651	if (idx[j] >= (int)rays.size())
1652	{
1653	idx[j] -= (int)rays.size();
1654
1655	chooseMin = (cminT < 2);
1656	}
1657	else
1658	chooseMin = (cmaxT < 2);
1659
1660	RayInfo rayInf = rays[idx[j]];
1661	pt[j] = chooseMin ? rayInf.ExtrapOrigin() : rayInf.ExtrapTermination();
1662	}
1663
1664	return Plane3(pt[0], pt[1], pt[2]);
1665	}
1666
1667
1668	Plane3 VspBspTree::ChooseCandidatePlane3(const RayInfoContainer &rays) const
1669	{
1670	Vector3 pt[3];
1671
1672	int idx1 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1673	int idx2 = (int)RandomValue(0, (Real)((int)rays.size() - 1));
1674
1675	// check if rays different
1676	if (idx1 == idx2)
1677	idx2 = (idx2 + 1) % (int)rays.size();
1678
1679	const RayInfo ray1 = rays[idx1];
1680	const RayInfo ray2 = rays[idx2];
1681
1682	// normal vector of the plane parallel to both lines
1683	const Vector3 norm = Normalize(CrossProd(ray1.mRay->GetDir(), ray2.mRay->GetDir()));
1684
1685	// vector from line 1 to line 2
1686	const Vector3 vd = ray2.ExtrapOrigin() - ray1.ExtrapOrigin();
1687
1688	// project vector on normal to get distance
1689	const float dist = DotProd(vd, norm);
1690
1691	// point on plane lies halfway between the two planes
1692	const Vector3 planePt = ray1.ExtrapOrigin() + norm * dist * 0.5;
1693
1694	return Plane3(norm, planePt);
1695	}
1696
1697
1698	inline void VspBspTree::GenerateUniqueIdsForPvs()
1699	{
1700	Intersectable::NewMail(); sBackId = Intersectable::sMailId;
1701	Intersectable::NewMail(); sFrontId = Intersectable::sMailId;
1702	Intersectable::NewMail(); sFrontAndBackId = Intersectable::sMailId;
1703	}
1704
1705
1706	float VspBspTree::EvalRenderCostDecrease(const Plane3 &candidatePlane,
1707	const VspBspTraversalData &data) const
1708	{
1709	float pvsFront = 0;
1710	float pvsBack = 0;
1711	float totalPvs = 0;
1712
1713	// probability that view point lies in back / front node
1714	float pOverall = data.mProbability;
1715	float pFront = 0;
1716	float pBack = 0;
1717
1718
1719	// create unique ids for pvs heuristics
1720	GenerateUniqueIdsForPvs();
1721
1722	for (int i = 0; i < data.mRays->size(); ++ i)
1723	{
1724	RayInfo rayInf = (*data.mRays)[i];
1725
1726	float t;
1727	VssRay *ray = rayInf.mRay;
1728	const int cf = rayInf.ComputeRayIntersection(candidatePlane, t);
1729
1730	// find front and back pvs for origing and termination object
1731	AddObjToPvs(ray->mTerminationObject, cf, pvsFront, pvsBack, totalPvs);
1732	AddObjToPvs(ray->mOriginObject, cf, pvsFront, pvsBack, totalPvs);
1733	}
1734
1735
1736	BspNodeGeometry geomFront;
1737	BspNodeGeometry geomBack;
1738
1739	// construct child geometry with regard to the candidate split plane
1740	data.mGeometry->SplitGeometry(geomFront,
1741	geomBack,
1742	candidatePlane,
1743	mBox,
1744	//0.0f);
1745	mEpsilon);
1746
1747	if (!mUseAreaForPvs) // use front and back cell areas to approximate volume
1748	{
1749	pFront = geomFront.GetVolume();
1750	pBack = pOverall - pFront;
1751
1752	// something is wrong with the volume
1753	if ((pFront < 0.0) \|\| (pBack < 0.0))
1754	{
1755	Debug << "vol f " << pFront << " b " << pBack << " p " << pOverall << endl;
1756	Debug << "real vol f " << pFront << " b " << geomBack.GetVolume() << " p " << pOverall << endl;
1757	Debug << "polys f " << geomFront.Size() << " b " << geomBack.Size() << " data " << data.mGeometry->Size() << endl;
1758	}
1759
1760	// clamp because of possible precision issues
1761	if (0)
1762	{
1763	if (pFront < 0) pFront = 0;
1764	if (pBack < 0) pBack = 0;
1765	}
1766	}
1767	else
1768	{
1769	pFront = geomFront.GetArea();
1770	pBack = geomBack.GetArea();
1771	}
1772
1773
1774	// -- pvs rendering heuristics
1775	const int lowerPvsLimit = mViewCellsManager->GetMinPvsSize();
1776	const int upperPvsLimit = mViewCellsManager->GetMaxPvsSize();
1777
1778	// only render cost heuristics or combined with standard deviation
1779	const float penaltyOld = EvalPvsPenalty(totalPvs, lowerPvsLimit, upperPvsLimit);
1780	const float penaltyFront = EvalPvsPenalty(pvsFront, lowerPvsLimit, upperPvsLimit);
1781	const float penaltyBack = EvalPvsPenalty(pvsBack, lowerPvsLimit, upperPvsLimit);
1782
1783	const float oldRenderCost = pOverall * penaltyOld;
1784	const float newRenderCost = penaltyFront * pFront + penaltyBack * pBack;
1785
1786	//Debug << "decrease: " << oldRenderCost - newRenderCost << endl;
1787	return (oldRenderCost - newRenderCost) / mBox.GetVolume();
1788	}
1789
1790
1791	float VspBspTree::EvalSplitPlaneCost(const Plane3 &candidatePlane,
1792	const VspBspTraversalData &data,
1793	BspNodeGeometry &geomFront,
1794	BspNodeGeometry &geomBack,
1795	float &pFront,
1796	float &pBack) const
1797	{
1798	float cost = 0;
1799
1800	float totalPvs = 0;
1801	float pvsFront = 0;
1802	float pvsBack = 0;
1803
1804	// probability that view point lies in back / front node
1805	float pOverall = 0;
1806	pFront = 0;
1807	pBack = 0;
1808
1809
1810	int limit;
1811	bool useRand;
1812
1813	// create unique ids for pvs heuristics
1814	GenerateUniqueIdsForPvs();
1815
1816	// choose test rays randomly if too much
1817	if ((int)data.mRays->size() > mMaxTests)
1818	{
1819	useRand = true;
1820	limit = mMaxTests;
1821	}
1822	else
1823	{
1824	useRand = false;
1825	limit = (int)data.mRays->size();
1826	}
1827
1828	for (int i = 0; i < limit; ++ i)
1829	{
1830	const int testIdx = useRand ?
1831	(int)RandomValue(0, (Real)((int)data.mRays->size() - 1)) : i;
1832	RayInfo rayInf = (*data.mRays)[testIdx];
1833
1834	float t;
1835	VssRay *ray = rayInf.mRay;
1836	const int cf = rayInf.ComputeRayIntersection(candidatePlane, t);
1837
1838	// find front and back pvs for origing and termination object
1839	AddObjToPvs(ray->mTerminationObject, cf, pvsFront, pvsBack, totalPvs);
1840	AddObjToPvs(ray->mOriginObject, cf, pvsFront, pvsBack, totalPvs);
1841	}
1842
1843	// construct child geometry with regard to the candidate split plane
1844	bool splitSuccessFull = data.mGeometry->SplitGeometry(geomFront,
1845	geomBack,
1846	candidatePlane,
1847	mBox,
1848	//0.0f);
1849	mEpsilon);
1850
1851	pOverall = data.mProbability;
1852
1853	if (!mUseAreaForPvs) // use front and back cell areas to approximate volume
1854	{
1855	pFront = geomFront.GetVolume();
1856	pBack = pOverall - pFront;
1857
1858	// HACK: precision issues possible for unbalanced split => don't take this split!
1859	if (1 &&
1860	(!splitSuccessFull \|\| (pFront <= 0) \|\| (pBack <= 0) \|\|
1861	!geomFront.Valid() \|\| !geomBack.Valid()))
1862	{
1863	Debug << "error f: " << pFront << " b: " << pBack << endl;
1864	return 99999.9f;
1865	}
1866	}
1867	else
1868	{
1869	pFront = geomFront.GetArea();
1870	pBack = geomBack.GetArea();
1871	}
1872
1873
1874	// -- pvs rendering heuristics
1875	const int lowerPvsLimit = mViewCellsManager->GetMinPvsSize();
1876	const int upperPvsLimit = mViewCellsManager->GetMaxPvsSize();
1877
1878	// only render cost heuristics or combined with standard deviation
1879	const float penaltyOld = EvalPvsPenalty(totalPvs, lowerPvsLimit, upperPvsLimit);
1880	const float penaltyFront = EvalPvsPenalty(pvsFront, lowerPvsLimit, upperPvsLimit);
1881	const float penaltyBack = EvalPvsPenalty(pvsBack, lowerPvsLimit, upperPvsLimit);
1882
1883	const float oldRenderCost = pOverall * penaltyOld;
1884	const float newRenderCost = penaltyFront * pFront + penaltyBack * pBack;
1885
1886	float oldCost, newCost;
1887
1888	// only render cost
1889	if (1)
1890	{
1891	oldCost = oldRenderCost;
1892	newCost = newRenderCost;
1893	}
1894	else // also considering standard deviation
1895	{
1896	// standard deviation is difference of back and front pvs
1897	const float expectedCost = 0.5f * (penaltyFront + penaltyBack);
1898
1899	const float newDeviation = 0.5f *
1900	fabs(penaltyFront - expectedCost) + fabs(penaltyBack - expectedCost);
1901
1902	const float oldDeviation = penaltyOld;
1903
1904	newCost = mRenderCostWeight * newRenderCost + (1.0f - mRenderCostWeight) * newDeviation;
1905	oldCost = mRenderCostWeight * oldRenderCost + (1.0f - mRenderCostWeight) * oldDeviation;
1906	}
1907
1908	cost += mPvsFactor * newCost / (oldCost + Limits::Small);
1909
1910
1911	#ifdef _DEBUG
1912	Debug << "totalpvs: " << data.mPvs << " ptotal: " << pOverall
1913	<< " frontpvs: " << pvsFront << " pFront: " << pFront
1914	<< " backpvs: " << pvsBack << " pBack: " << pBack << endl << endl;
1915	Debug << "cost: " << cost << endl;
1916	#endif
1917
1918	return cost;
1919	}
1920
1921
1922	int VspBspTree::ComputeBoxIntersections(const AxisAlignedBox3 &box,
1923	ViewCellContainer &viewCells) const
1924	{
1925	stack<bspNodePair> nodeStack;
1926	BspNodeGeometry *rgeom = new BspNodeGeometry();
1927
1928	ConstructGeometry(mRoot, *rgeom);
1929
1930	nodeStack.push(bspNodePair(mRoot, rgeom));
1931
1932	ViewCell::NewMail();
1933
1934	while (!nodeStack.empty())
1935	{
1936	BspNode *node = nodeStack.top().first;
1937	BspNodeGeometry *geom = nodeStack.top().second;
1938	nodeStack.pop();
1939
1940	const int side = geom->ComputeIntersection(box);
1941
1942	switch (side)
1943	{
1944	case -1:
1945	// node geometry is contained in box
1946	CollectViewCells(node, true, viewCells, true);
1947	break;
1948
1949	case 0:
1950	if (node->IsLeaf())
1951	{
1952	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
1953
1954	if (!leaf->GetViewCell()->Mailed() && leaf->TreeValid())
1955	{
1956	leaf->GetViewCell()->Mail();
1957	viewCells.push_back(leaf->GetViewCell());
1958	}
1959	}
1960	else
1961	{
1962	BspInterior interior = dynamic_cast<BspInterior >(node);
1963
1964	BspNode *first = interior->GetFront();
1965	BspNode *second = interior->GetBack();
1966
1967	BspNodeGeometry *firstGeom = new BspNodeGeometry();
1968	BspNodeGeometry *secondGeom = new BspNodeGeometry();
1969
1970	geom->SplitGeometry(*firstGeom,
1971	*secondGeom,
1972	interior->GetPlane(),
1973	mBox,
1974	//0.0000001f);
1975	mEpsilon);
1976
1977	nodeStack.push(bspNodePair(first, firstGeom));
1978	nodeStack.push(bspNodePair(second, secondGeom));
1979	}
1980
1981	break;
1982	default:
1983	// default: cull
1984	break;
1985	}
1986
1987	DEL_PTR(geom);
1988
1989	}
1990
1991	return (int)viewCells.size();
1992	}
1993
1994
1995	float VspBspTree::EvalAxisAlignedSplitCost(const VspBspTraversalData &data,
1996	const AxisAlignedBox3 &box,
1997	const int axis,
1998	const float &position,
1999	float &pFront,
2000	float &pBack) const
2001	{
2002	float pvsTotal = 0;
2003	float pvsFront = 0;
2004	float pvsBack = 0;
2005
2006	// create unique ids for pvs heuristics
2007	GenerateUniqueIdsForPvs();
2008
2009	const int pvsSize = data.mPvs;
2010
2011	RayInfoContainer::const_iterator rit, rit_end = data.mRays->end();
2012
2013	// this is the main ray classification loop!
2014	for(rit = data.mRays->begin(); rit != rit_end; ++ rit)
2015	{
2016	//if (!(*rit).mRay->IsActive()) continue;
2017
2018	// determine the side of this ray with respect to the plane
2019	float t;
2020	const int side = (*rit).ComputeRayIntersection(axis, position, t);
2021
2022	AddObjToPvs((*rit).mRay->mTerminationObject, side, pvsFront, pvsBack, pvsTotal);
2023	AddObjToPvs((*rit).mRay->mOriginObject, side, pvsFront, pvsBack, pvsTotal);
2024	}
2025
2026	//-- pvs heuristics
2027	float pOverall;
2028
2029	//-- compute heurstics
2030	// we take simplified computation for mid split
2031
2032	pOverall = data.mProbability;
2033
2034	if (!mUseAreaForPvs)
2035	{ // volume
2036	pBack = pFront = pOverall * 0.5f;
2037
2038	#if 0
2039	// box length substitute for probability
2040	const float minBox = box.Min(axis);
2041	const float maxBox = box.Max(axis);
2042
2043	pBack = position - minBox;
2044	pFront = maxBox - position;
2045	pOverall = maxBox - minBox;
2046	#endif
2047	}
2048	else //-- area substitute for probability
2049	{
2050	const int axis2 = (axis + 1) % 3;
2051	const int axis3 = (axis + 2) % 3;
2052
2053	const float faceArea =
2054	(box.Max(axis2) - box.Min(axis2)) *
2055	(box.Max(axis3) - box.Min(axis3));
2056
2057	pBack = pFront = pOverall * 0.5f + faceArea;
2058	}
2059
2060	#ifdef _DEBUG
2061	Debug << axis << " " << pvsSize << " " << pvsBack << " " << pvsFront << endl;
2062	Debug << pFront << " " << pBack << " " << pOverall << endl;
2063	#endif
2064
2065
2066	const float newCost = pvsBack * pBack + pvsFront * pFront;
2067	const float oldCost = (float)pvsSize * pOverall + Limits::Small;
2068
2069	return (mCtDivCi + newCost) / oldCost;
2070	}
2071
2072
2073	void VspBspTree::AddObjToPvs(Intersectable *obj,
2074	const int cf,
2075	float &frontPvs,
2076	float &backPvs,
2077	float &totalPvs) const
2078	{
2079	if (!obj)
2080	return;
2081
2082	// new object
2083	if ((obj->mMailbox != sFrontId) &&
2084	(obj->mMailbox != sBackId) &&
2085	(obj->mMailbox != sFrontAndBackId))
2086	{
2087	totalPvs += mViewCellsManager->EvalRenderCost(obj);
2088	}
2089
2090	// TODO: does this really belong to no pvs?
2091	//if (cf == Ray::COINCIDENT) return;
2092
2093	// object belongs to both PVS
2094	if (cf >= 0)
2095	{
2096	if ((obj->mMailbox != sFrontId) &&
2097	(obj->mMailbox != sFrontAndBackId))
2098	{
2099	frontPvs += mViewCellsManager->EvalRenderCost(obj);
2100
2101	if (obj->mMailbox == sBackId)
2102	obj->mMailbox = sFrontAndBackId;
2103	else
2104	obj->mMailbox = sFrontId;
2105	}
2106	}
2107
2108	if (cf <= 0)
2109	{
2110	if ((obj->mMailbox != sBackId) &&
2111	(obj->mMailbox != sFrontAndBackId))
2112	{
2113	backPvs += mViewCellsManager->EvalRenderCost(obj);;
2114
2115	if (obj->mMailbox == sFrontId)
2116	obj->mMailbox = sFrontAndBackId;
2117	else
2118	obj->mMailbox = sBackId;
2119	}
2120	}
2121	}
2122
2123
2124	void VspBspTree::CollectLeaves(vector<BspLeaf *> &leaves,
2125	const bool onlyUnmailed,
2126	const int maxPvsSize) const
2127	{
2128	stack<BspNode *> nodeStack;
2129	nodeStack.push(mRoot);
2130
2131	while (!nodeStack.empty())
2132	{
2133	BspNode *node = nodeStack.top();
2134	nodeStack.pop();
2135
2136	if (node->IsLeaf())
2137	{
2138	// test if this leaf is in valid view space
2139	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2140	if (leaf->TreeValid() &&
2141	(!onlyUnmailed \|\| !leaf->Mailed()) &&
2142	((maxPvsSize < 0) \|\| (leaf->GetViewCell()->GetPvs().GetSize() <= maxPvsSize)))
2143	{
2144	leaves.push_back(leaf);
2145	}
2146	}
2147	else
2148	{
2149	BspInterior interior = dynamic_cast<BspInterior >(node);
2150
2151	nodeStack.push(interior->GetBack());
2152	nodeStack.push(interior->GetFront());
2153	}
2154	}
2155	}
2156
2157
2158	AxisAlignedBox3 VspBspTree::GetBoundingBox() const
2159	{
2160	return mBox;
2161	}
2162
2163
2164	BspNode *VspBspTree::GetRoot() const
2165	{
2166	return mRoot;
2167	}
2168
2169
2170	void VspBspTree::EvaluateLeafStats(const VspBspTraversalData &data)
2171	{
2172	// the node became a leaf -> evaluate stats for leafs
2173	BspLeaf leaf = dynamic_cast<BspLeaf >(data.mNode);
2174
2175
2176	if (data.mPvs > mBspStats.maxPvs)
2177	{
2178	mBspStats.maxPvs = data.mPvs;
2179	}
2180
2181	mBspStats.pvs += data.mPvs;
2182
2183	if (data.mDepth < mBspStats.minDepth)
2184	{
2185	mBspStats.minDepth = data.mDepth;
2186	}
2187
2188	if (data.mDepth >= mTermMaxDepth)
2189	{
2190	++ mBspStats.maxDepthNodes;
2191	}
2192
2193	// accumulate rays to compute rays / leaf
2194	mBspStats.accumRays += (int)data.mRays->size();
2195
2196	if (data.mPvs < mTermMinPvs)
2197	++ mBspStats.minPvsNodes;
2198
2199	if ((int)data.mRays->size() < mTermMinRays)
2200	++ mBspStats.minRaysNodes;
2201
2202	if (data.GetAvgRayContribution() > mTermMaxRayContribution)
2203	++ mBspStats.maxRayContribNodes;
2204
2205	if (data.mProbability <= mTermMinProbability)
2206	++ mBspStats.minProbabilityNodes;
2207
2208	// accumulate depth to compute average depth
2209	mBspStats.accumDepth += data.mDepth;
2210
2211	++ mCreatedViewCells;
2212
2213	#ifdef _DEBUG
2214	Debug << "BSP stats: "
2215	<< "Depth: " << data.mDepth << " (max: " << mTermMaxDepth << "), "
2216	<< "PVS: " << data.mPvs << " (min: " << mTermMinPvs << "), "
2217	// << "Area: " << data.mProbability << " (min: " << mTermMinProbability << "), "
2218	<< "#rays: " << (int)data.mRays->size() << " (max: " << mTermMinRays << "), "
2219	<< "#pvs: " << leaf->GetViewCell()->GetPvs().GetSize() << "=, "
2220	<< "#avg ray contrib (pvs): " << (float)data.mPvs / (float)data.mRays->size() << endl;
2221	#endif
2222	}
2223
2224
2225	int VspBspTree::CastRay(Ray &ray)
2226	{
2227	int hits = 0;
2228
2229	stack<BspRayTraversalData> tQueue;
2230
2231	float maxt, mint;
2232
2233	if (!mBox.GetRaySegment(ray, mint, maxt))
2234	return 0;
2235
2236	Intersectable::NewMail();
2237	ViewCell::NewMail();
2238	Vector3 entp = ray.Extrap(mint);
2239	Vector3 extp = ray.Extrap(maxt);
2240
2241	BspNode *node = mRoot;
2242	BspNode *farChild = NULL;
2243
2244	while (1)
2245	{
2246	if (!node->IsLeaf())
2247	{
2248	BspInterior in = dynamic_cast<BspInterior >(node);
2249
2250	Plane3 splitPlane = in->GetPlane();
2251	const int entSide = splitPlane.Side(entp);
2252	const int extSide = splitPlane.Side(extp);
2253
2254	if (entSide < 0)
2255	{
2256	node = in->GetBack();
2257
2258	if(extSide <= 0) // plane does not split ray => no far child
2259	continue;
2260
2261	farChild = in->GetFront(); // plane splits ray
2262
2263	} else if (entSide > 0)
2264	{
2265	node = in->GetFront();
2266
2267	if (extSide >= 0) // plane does not split ray => no far child
2268	continue;
2269
2270	farChild = in->GetBack(); // plane splits ray
2271	}
2272	else // ray and plane are coincident
2273	{
2274	// WHAT TO DO IN THIS CASE ?
2275	//break;
2276	node = in->GetFront();
2277	continue;
2278	}
2279
2280	// push data for far child
2281	tQueue.push(BspRayTraversalData(farChild, extp, maxt));
2282
2283	// find intersection of ray segment with plane
2284	float t;
2285	extp = splitPlane.FindIntersection(ray.GetLoc(), extp, &t);
2286	maxt *= t;
2287
2288	} else // reached leaf => intersection with view cell
2289	{
2290	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2291
2292	if (!leaf->GetViewCell()->Mailed())
2293	{
2294	//ray.bspIntersections.push_back(Ray::VspBspIntersection(maxt, leaf));
2295	leaf->GetViewCell()->Mail();
2296	++ hits;
2297	}
2298
2299	//-- fetch the next far child from the stack
2300	if (tQueue.empty())
2301	break;
2302
2303	entp = extp;
2304	mint = maxt; // NOTE: need this?
2305
2306	if (ray.GetType() == Ray::LINE_SEGMENT && mint > 1.0f)
2307	break;
2308
2309	BspRayTraversalData &s = tQueue.top();
2310
2311	node = s.mNode;
2312	extp = s.mExitPoint;
2313	maxt = s.mMaxT;
2314
2315	tQueue.pop();
2316	}
2317	}
2318
2319	return hits;
2320	}
2321
2322
2323	void VspBspTree::CollectViewCells(ViewCellContainer &viewCells, bool onlyValid) const
2324	{
2325	ViewCell::NewMail();
2326
2327	CollectViewCells(mRoot, onlyValid, viewCells, true);
2328	}
2329
2330
2331	void VspBspTree::CollapseViewCells()
2332	{
2333	// TODO
2334	#if HAS_TO_BE_REDONE
2335	stack<BspNode *> nodeStack;
2336
2337	if (!mRoot)
2338	return;
2339
2340	nodeStack.push(mRoot);
2341
2342	while (!nodeStack.empty())
2343	{
2344	BspNode *node = nodeStack.top();
2345	nodeStack.pop();
2346
2347	if (node->IsLeaf())
2348	{
2349	BspViewCell viewCell = dynamic_cast<BspLeaf >(node)->GetViewCell();
2350
2351	if (!viewCell->GetValid())
2352	{
2353	BspViewCell viewCell = dynamic_cast<BspLeaf >(node)->GetViewCell();
2354
2355	ViewCellContainer leaves;
2356	mViewCellsTree->CollectLeaves(viewCell, leaves);
2357
2358	ViewCellContainer::const_iterator it, it_end = leaves.end();
2359
2360	for (it = leaves.begin(); it != it_end; ++ it)
2361	{
2362	BspLeaf l = dynamic_cast<BspViewCell >(*it)->mLeaf;
2363	l->SetViewCell(GetOrCreateOutOfBoundsCell());
2364	++ mBspStats.invalidLeaves;
2365	}
2366
2367	// add to unbounded view cell
2368	GetOrCreateOutOfBoundsCell()->GetPvs().AddPvs(viewCell->GetPvs());
2369	DEL_PTR(viewCell);
2370	}
2371	}
2372	else
2373	{
2374	BspInterior interior = dynamic_cast<BspInterior >(node);
2375
2376	nodeStack.push(interior->GetFront());
2377	nodeStack.push(interior->GetBack());
2378	}
2379	}
2380
2381	Debug << "invalid leaves: " << mBspStats.invalidLeaves << endl;
2382	#endif
2383	}
2384
2385
2386	void VspBspTree::CollectRays(VssRayContainer &rays)
2387	{
2388	vector<BspLeaf *> leaves;
2389
2390	vector<BspLeaf *>::const_iterator lit, lit_end = leaves.end();
2391
2392	for (lit = leaves.begin(); lit != lit_end; ++ lit)
2393	{
2394	BspLeaf leaf = lit;
2395	VssRayContainer::const_iterator rit, rit_end = leaf->mVssRays.end();
2396
2397	for (rit = leaf->mVssRays.begin(); rit != rit_end; ++ rit)
2398	rays.push_back(*rit);
2399	}
2400	}
2401
2402
2403	void VspBspTree::ValidateTree()
2404	{
2405	stack<BspNode *> nodeStack;
2406
2407	if (!mRoot)
2408	return;
2409
2410	nodeStack.push(mRoot);
2411
2412	mBspStats.invalidLeaves = 0;
2413	while (!nodeStack.empty())
2414	{
2415	BspNode *node = nodeStack.top();
2416	nodeStack.pop();
2417
2418	if (node->IsLeaf())
2419	{
2420	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
2421
2422	if (!leaf->GetViewCell()->GetValid())
2423	++ mBspStats.invalidLeaves;
2424
2425	// validity flags don't match => repair
2426	if (leaf->GetViewCell()->GetValid() != leaf->TreeValid())
2427	{
2428	leaf->SetTreeValid(leaf->GetViewCell()->GetValid());
2429	PropagateUpValidity(leaf);
2430	}
2431	}
2432	else
2433	{
2434	BspInterior interior = dynamic_cast<BspInterior >(node);
2435
2436	nodeStack.push(interior->GetFront());
2437	nodeStack.push(interior->GetBack());
2438	}
2439	}
2440
2441	Debug << "invalid leaves: " << mBspStats.invalidLeaves << endl;
2442	}
2443
2444
2445
2446	void VspBspTree::CollectViewCells(BspNode *root,
2447	bool onlyValid,
2448	ViewCellContainer &viewCells,
2449	bool onlyUnmailed) const
2450	{
2451	stack<BspNode *> nodeStack;
2452
2453	if (!root)
2454	return;
2455
2456	nodeStack.push(root);
2457
2458	while (!nodeStack.empty())
2459	{
2460	BspNode *node = nodeStack.top();
2461	nodeStack.pop();
2462
2463	if (node->IsLeaf())
2464	{
2465	if (!onlyValid \|\| node->TreeValid())
2466	{
2467	ViewCell leafVc = dynamic_cast<BspLeaf >(node)->GetViewCell();
2468
2469	ViewCell *viewCell = mViewCellsTree->GetActiveViewCell(leafVc);
2470
2471	if (!onlyUnmailed \|\| !viewCell->Mailed())
2472	{
2473	viewCell->Mail();
2474	viewCells.push_back(viewCell);
2475	}
2476	}
2477	}
2478	else
2479	{
2480	BspInterior interior = dynamic_cast<BspInterior >(node);
2481
2482	nodeStack.push(interior->GetFront());
2483	nodeStack.push(interior->GetBack());
2484	}
2485	}
2486
2487	}
2488
2489
2490	void VspBspTree::PreprocessPolygons(PolygonContainer &polys)
2491	{
2492	// preprocess: throw out polygons coincident to the view space box (not needed)
2493	PolygonContainer boxPolys;
2494	mBox.ExtractPolys(boxPolys);
2495	vector<Plane3> boxPlanes;
2496
2497	PolygonContainer::iterator pit, pit_end = boxPolys.end();
2498
2499	// extract planes of box
2500	// TODO: can be done more elegantly than first extracting polygons
2501	// and take their planes
2502	for (pit = boxPolys.begin(); pit != pit_end; ++ pit)
2503	{
2504	boxPlanes.push_back((*pit)->GetSupportingPlane());
2505	}
2506
2507	pit_end = polys.end();
2508
2509	for (pit = polys.begin(); pit != pit_end; ++ pit)
2510	{
2511	vector<Plane3>::const_iterator bit, bit_end = boxPlanes.end();
2512
2513	for (bit = boxPlanes.begin(); (bit != bit_end) && (*pit); ++ bit)
2514	{
2515	const int cf = (pit)->ClassifyPlane(bit, mEpsilon);
2516
2517	if (cf == Polygon3::COINCIDENT)
2518	{
2519	DEL_PTR(*pit);
2520	//Debug << "coincident!!" << endl;
2521	}
2522	}
2523	}
2524
2525	// remove deleted entries
2526	for (int i = 0; i < (int)polys.size(); ++ i)
2527	{
2528	while (!polys[i] && (i < (int)polys.size()))
2529	{
2530	swap(polys[i], polys.back());
2531	polys.pop_back();
2532	}
2533	}
2534	}
2535
2536
2537	float VspBspTree::AccumulatedRayLength(const RayInfoContainer &rays) const
2538	{
2539	float len = 0;
2540
2541	RayInfoContainer::const_iterator it, it_end = rays.end();
2542
2543	for (it = rays.begin(); it != it_end; ++ it)
2544	len += (*it).SegmentLength();
2545
2546	return len;
2547	}
2548
2549
2550	int VspBspTree::SplitRays(const Plane3 &plane,
2551	RayInfoContainer &rays,
2552	RayInfoContainer &frontRays,
2553	RayInfoContainer &backRays) const
2554	{
2555	int splits = 0;
2556
2557	RayInfoContainer::const_iterator it, it_end = rays.end();
2558
2559	for (it = rays.begin(); it != it_end; ++ it)
2560	{
2561	RayInfo bRay = *it;
2562
2563	VssRay *ray = bRay.mRay;
2564	float t;
2565
2566	// get classification and receive new t
2567	const int cf = bRay.ComputeRayIntersection(plane, t);
2568
2569	switch (cf)
2570	{
2571	case -1:
2572	backRays.push_back(bRay);
2573	break;
2574	case 1:
2575	frontRays.push_back(bRay);
2576	break;
2577	case 0:
2578	{
2579	//-- split ray
2580	// test if start point behind or in front of plane
2581	const int side = plane.Side(bRay.ExtrapOrigin());
2582
2583	if (side <= 0)
2584	{
2585	backRays.push_back(RayInfo(ray, bRay.GetMinT(), t));
2586	frontRays.push_back(RayInfo(ray, t, bRay.GetMaxT()));
2587	}
2588	else
2589	{
2590	frontRays.push_back(RayInfo(ray, bRay.GetMinT(), t));
2591	backRays.push_back(RayInfo(ray, t, bRay.GetMaxT()));
2592	}
2593	}
2594	break;
2595	default:
2596	Debug << "Should not come here" << endl;
2597	break;
2598	}
2599	}
2600
2601	return splits;
2602	}
2603
2604
2605	void VspBspTree::ExtractHalfSpaces(BspNode *n, vector<Plane3> &halfSpaces) const
2606	{
2607	BspNode *lastNode;
2608
2609	do
2610	{
2611	lastNode = n;
2612
2613	// want to get planes defining geometry of this node => don't take
2614	// split plane of node itself
2615	n = n->GetParent();
2616
2617	if (n)
2618	{
2619	BspInterior interior = dynamic_cast<BspInterior >(n);
2620	Plane3 halfSpace = dynamic_cast<BspInterior *>(interior)->GetPlane();
2621
2622	if (interior->GetBack() != lastNode)
2623	halfSpace.ReverseOrientation();
2624
2625	halfSpaces.push_back(halfSpace);
2626	}
2627	}
2628	while (n);
2629	}
2630
2631
2632	void VspBspTree::ConstructGeometry(BspNode *n,
2633	BspNodeGeometry &geom) const
2634	{
2635	vector<Plane3> halfSpaces;
2636	ExtractHalfSpaces(n, halfSpaces);
2637
2638	PolygonContainer candidatePolys;
2639	vector<Plane3> candidatePlanes;
2640
2641	vector<Plane3>::const_iterator pit, pit_end = halfSpaces.end();
2642
2643	// bounded planes are added to the polygons
2644	for (pit = halfSpaces.begin(); pit != pit_end; ++ pit)
2645	{
2646	Polygon3 p = GetBoundingBox().CrossSection(pit);
2647
2648	if (p->Valid(mEpsilon))
2649	{
2650	candidatePolys.push_back(p);
2651	candidatePlanes.push_back(*pit);
2652	}
2653	}
2654
2655	// add faces of bounding box (also could be faces of the cell)
2656	for (int i = 0; i < 6; ++ i)
2657	{
2658	VertexContainer vertices;
2659
2660	for (int j = 0; j < 4; ++ j)
2661	vertices.push_back(mBox.GetFace(i).mVertices[j]);
2662
2663	Polygon3 *poly = new Polygon3(vertices);
2664
2665	candidatePolys.push_back(poly);
2666	candidatePlanes.push_back(poly->GetSupportingPlane());
2667	}
2668
2669	for (int i = 0; i < (int)candidatePolys.size(); ++ i)
2670	{
2671	// polygon is split by all other planes
2672	for (int j = 0; (j < (int)halfSpaces.size()) && candidatePolys[i]; ++ j)
2673	{
2674	if (i == j) // polygon and plane are coincident
2675	continue;
2676
2677	VertexContainer splitPts;
2678	Polygon3 frontPoly, backPoly;
2679
2680	const int cf =
2681	candidatePolys[i]->ClassifyPlane(halfSpaces[j],
2682	mEpsilon);
2683
2684	switch (cf)
2685	{
2686	case Polygon3::SPLIT:
2687	frontPoly = new Polygon3();
2688	backPoly = new Polygon3();
2689
2690	candidatePolys[i]->Split(halfSpaces[j],
2691	*frontPoly,
2692	*backPoly,
2693	mEpsilon);
2694
2695	DEL_PTR(candidatePolys[i]);
2696
2697	if (backPoly->Valid(mEpsilon))
2698	candidatePolys[i] = backPoly;
2699	else
2700	DEL_PTR(backPoly);
2701
2702	// outside, don't need this
2703	DEL_PTR(frontPoly);
2704	break;
2705	// polygon outside of halfspace
2706	case Polygon3::FRONT_SIDE:
2707	DEL_PTR(candidatePolys[i]);
2708	break;
2709	// just take polygon as it is
2710	case Polygon3::BACK_SIDE:
2711	case Polygon3::COINCIDENT:
2712	default:
2713	break;
2714	}
2715	}
2716
2717	if (candidatePolys[i])
2718	{
2719	geom.Add(candidatePolys[i], candidatePlanes[i]);
2720	// geom.mPolys.push_back(candidates[i]);
2721	}
2722	}
2723	}
2724
2725
2726	void VspBspTree::ConstructGeometry(ViewCell *vc,
2727	BspNodeGeometry &vcGeom) const
2728	{
2729	ViewCellContainer leaves;
2730
2731	mViewCellsTree->CollectLeaves(vc, leaves);
2732
2733	ViewCellContainer::const_iterator it, it_end = leaves.end();
2734
2735	for (it = leaves.begin(); it != it_end; ++ it)
2736	{
2737	BspLeaf l = dynamic_cast<BspViewCell >(*it)->mLeaf;
2738
2739	ConstructGeometry(l, vcGeom);
2740	}
2741	}
2742
2743
2744	int VspBspTree::FindNeighbors(BspNode n, vector<BspLeaf > &neighbors,
2745	const bool onlyUnmailed) const
2746	{
2747	stack<bspNodePair> nodeStack;
2748
2749	BspNodeGeometry nodeGeom;
2750	ConstructGeometry(n, nodeGeom);
2751
2752	// split planes from the root to this node
2753	// needed to verify that we found neighbor leaf
2754	// TODO: really needed?
2755	vector<Plane3> halfSpaces;
2756	ExtractHalfSpaces(n, halfSpaces);
2757
2758
2759	BspNodeGeometry *rgeom = new BspNodeGeometry();
2760	ConstructGeometry(mRoot, *rgeom);
2761
2762	nodeStack.push(bspNodePair(mRoot, rgeom));
2763
2764	while (!nodeStack.empty())
2765	{
2766	BspNode *node = nodeStack.top().first;
2767	BspNodeGeometry *geom = nodeStack.top().second;
2768
2769	nodeStack.pop();
2770
2771	if (node->IsLeaf())
2772	{
2773	// test if this leaf is in valid view space
2774	if (node->TreeValid() &&
2775	(node != n) &&
2776	(!onlyUnmailed \|\| !node->Mailed()))
2777	{
2778	bool isAdjacent = true;
2779
2780	if (1)
2781	{
2782	// test all planes of current node if still adjacent
2783	for (int i = 0; (i < halfSpaces.size()) && isAdjacent; ++ i)
2784	{
2785	const int cf =
2786	Polygon3::ClassifyPlane(geom->GetPolys(),
2787	halfSpaces[i],
2788	mEpsilon);
2789
2790	if (cf == Polygon3::FRONT_SIDE)
2791	{
2792	isAdjacent = false;
2793	}
2794	}
2795	}
2796	else
2797	{
2798	// TODO: why is this wrong??
2799	// test all planes of current node if still adjacent
2800	for (int i = 0; (i < nodeGeom.Size()) && isAdjacent; ++ i)
2801	{
2802	Polygon3 *poly = nodeGeom.GetPolys()[i];
2803
2804	const int cf =
2805	Polygon3::ClassifyPlane(geom->GetPolys(),
2806	poly->GetSupportingPlane(),
2807	mEpsilon);
2808
2809	if (cf == Polygon3::FRONT_SIDE)
2810	{
2811	isAdjacent = false;
2812	}
2813	}
2814	}
2815	// neighbor was found
2816	if (isAdjacent)
2817	{
2818	neighbors.push_back(dynamic_cast<BspLeaf *>(node));
2819	}
2820	}
2821	}
2822	else
2823	{
2824	BspInterior interior = dynamic_cast<BspInterior >(node);
2825
2826	const int cf = Polygon3::ClassifyPlane(nodeGeom.GetPolys(),
2827	interior->GetPlane(),
2828	mEpsilon);
2829
2830	BspNode *front = interior->GetFront();
2831	BspNode *back = interior->GetBack();
2832
2833	BspNodeGeometry *fGeom = new BspNodeGeometry();
2834	BspNodeGeometry *bGeom = new BspNodeGeometry();
2835
2836	geom->SplitGeometry(*fGeom,
2837	*bGeom,
2838	interior->GetPlane(),
2839	mBox,
2840	//0.0000001f);
2841	mEpsilon);
2842
2843	if (cf == Polygon3::BACK_SIDE)
2844	{
2845	nodeStack.push(bspNodePair(interior->GetBack(), bGeom));
2846	DEL_PTR(fGeom);
2847	}
2848	else
2849	{
2850	if (cf == Polygon3::FRONT_SIDE)
2851	{
2852	nodeStack.push(bspNodePair(interior->GetFront(), fGeom));
2853	DEL_PTR(bGeom);
2854	}
2855	else
2856	{ // random decision
2857	nodeStack.push(bspNodePair(front, fGeom));
2858	nodeStack.push(bspNodePair(back, bGeom));
2859	}
2860	}
2861	}
2862
2863	DEL_PTR(geom);
2864	}
2865
2866	return (int)neighbors.size();
2867	}
2868
2869
2870
2871	int VspBspTree::FindApproximateNeighbors(BspNode *n,
2872	vector<BspLeaf *> &neighbors,
2873	const bool onlyUnmailed) const
2874	{
2875	stack<bspNodePair> nodeStack;
2876
2877	BspNodeGeometry nodeGeom;
2878	ConstructGeometry(n, nodeGeom);
2879
2880	// split planes from the root to this node
2881	// needed to verify that we found neighbor leaf
2882	// TODO: really needed?
2883	vector<Plane3> halfSpaces;
2884	ExtractHalfSpaces(n, halfSpaces);
2885
2886
2887	BspNodeGeometry *rgeom = new BspNodeGeometry();
2888	ConstructGeometry(mRoot, *rgeom);
2889
2890	nodeStack.push(bspNodePair(mRoot, rgeom));
2891
2892	while (!nodeStack.empty())
2893	{
2894	BspNode *node = nodeStack.top().first;
2895	BspNodeGeometry *geom = nodeStack.top().second;
2896
2897	nodeStack.pop();
2898
2899	if (node->IsLeaf())
2900	{
2901	// test if this leaf is in valid view space
2902	if (node->TreeValid() &&
2903	(node != n) &&
2904	(!onlyUnmailed \|\| !node->Mailed()))
2905	{
2906	bool isAdjacent = true;
2907
2908	// neighbor was found
2909	if (isAdjacent)
2910	{
2911	neighbors.push_back(dynamic_cast<BspLeaf *>(node));
2912	}
2913	}
2914	}
2915	else
2916	{
2917	BspInterior interior = dynamic_cast<BspInterior >(node);
2918
2919	const int cf = Polygon3::ClassifyPlane(nodeGeom.GetPolys(),
2920	interior->GetPlane(),
2921	mEpsilon);
2922
2923	BspNode *front = interior->GetFront();
2924	BspNode *back = interior->GetBack();
2925
2926	BspNodeGeometry *fGeom = new BspNodeGeometry();
2927	BspNodeGeometry *bGeom = new BspNodeGeometry();
2928
2929	geom->SplitGeometry(*fGeom,
2930	*bGeom,
2931	interior->GetPlane(),
2932	mBox,
2933	//0.0000001f);
2934	mEpsilon);
2935
2936	if (cf == Polygon3::BACK_SIDE)
2937	{
2938	nodeStack.push(bspNodePair(interior->GetBack(), bGeom));
2939	DEL_PTR(fGeom);
2940	}
2941	else
2942	{
2943	if (cf == Polygon3::FRONT_SIDE)
2944	{
2945	nodeStack.push(bspNodePair(interior->GetFront(), fGeom));
2946	DEL_PTR(bGeom);
2947	}
2948	else
2949	{ // random decision
2950	nodeStack.push(bspNodePair(front, fGeom));
2951	nodeStack.push(bspNodePair(back, bGeom));
2952	}
2953	}
2954	}
2955
2956	DEL_PTR(geom);
2957	}
2958
2959	return (int)neighbors.size();
2960	}
2961
2962
2963
2964	BspLeaf *VspBspTree::GetRandomLeaf(const Plane3 &halfspace)
2965	{
2966	stack<BspNode *> nodeStack;
2967	nodeStack.push(mRoot);
2968
2969	int mask = rand();
2970
2971	while (!nodeStack.empty())
2972	{
2973	BspNode *node = nodeStack.top();
2974	nodeStack.pop();
2975
2976	if (node->IsLeaf())
2977	{
2978	return dynamic_cast<BspLeaf *>(node);
2979	}
2980	else
2981	{
2982	BspInterior interior = dynamic_cast<BspInterior >(node);
2983	BspNode *next;
2984	BspNodeGeometry geom;
2985
2986	// todo: not very efficient: constructs full cell everytime
2987	ConstructGeometry(interior, geom);
2988
2989	const int cf =
2990	Polygon3::ClassifyPlane(geom.GetPolys(), halfspace, mEpsilon);
2991
2992	if (cf == Polygon3::BACK_SIDE)
2993	next = interior->GetFront();
2994	else
2995	if (cf == Polygon3::FRONT_SIDE)
2996	next = interior->GetFront();
2997	else
2998	{
2999	// random decision
3000	if (mask & 1)
3001	next = interior->GetBack();
3002	else
3003	next = interior->GetFront();
3004	mask = mask >> 1;
3005	}
3006
3007	nodeStack.push(next);
3008	}
3009	}
3010
3011	return NULL;
3012	}
3013
3014
3015	BspLeaf *VspBspTree::GetRandomLeaf(const bool onlyUnmailed)
3016	{
3017	stack<BspNode *> nodeStack;
3018
3019	nodeStack.push(mRoot);
3020
3021	int mask = rand();
3022
3023	while (!nodeStack.empty())
3024	{
3025	BspNode *node = nodeStack.top();
3026	nodeStack.pop();
3027
3028	if (node->IsLeaf())
3029	{
3030	if ( (!onlyUnmailed \|\| !node->Mailed()) )
3031	return dynamic_cast<BspLeaf *>(node);
3032	}
3033	else
3034	{
3035	BspInterior interior = dynamic_cast<BspInterior >(node);
3036
3037	// random decision
3038	if (mask & 1)
3039	nodeStack.push(interior->GetBack());
3040	else
3041	nodeStack.push(interior->GetFront());
3042
3043	mask = mask >> 1;
3044	}
3045	}
3046
3047	return NULL;
3048	}
3049
3050
3051	int VspBspTree::ComputePvsSize(const RayInfoContainer &rays) const
3052	{
3053	int pvsSize = 0;
3054
3055	RayInfoContainer::const_iterator rit, rit_end = rays.end();
3056
3057	Intersectable::NewMail();
3058
3059	for (rit = rays.begin(); rit != rays.end(); ++ rit)
3060	{
3061	VssRay ray = (rit).mRay;
3062
3063	if (ray->mOriginObject)
3064	{
3065	if (!ray->mOriginObject->Mailed())
3066	{
3067	ray->mOriginObject->Mail();
3068	++ pvsSize;
3069	}
3070	}
3071	if (ray->mTerminationObject)
3072	{
3073	if (!ray->mTerminationObject->Mailed())
3074	{
3075	ray->mTerminationObject->Mail();
3076	++ pvsSize;
3077	}
3078	}
3079	}
3080
3081	return pvsSize;
3082	}
3083
3084
3085	float VspBspTree::GetEpsilon() const
3086	{
3087	return mEpsilon;
3088	}
3089
3090
3091	int VspBspTree::SplitPolygons(const Plane3 &plane,
3092	PolygonContainer &polys,
3093	PolygonContainer &frontPolys,
3094	PolygonContainer &backPolys,
3095	PolygonContainer &coincident) const
3096	{
3097	int splits = 0;
3098
3099	PolygonContainer::const_iterator it, it_end = polys.end();
3100
3101	for (it = polys.begin(); it != polys.end(); ++ it)
3102	{
3103	Polygon3 poly = it;
3104
3105	// classify polygon
3106	const int cf = poly->ClassifyPlane(plane, mEpsilon);
3107
3108	switch (cf)
3109	{
3110	case Polygon3::COINCIDENT:
3111	coincident.push_back(poly);
3112	break;
3113	case Polygon3::FRONT_SIDE:
3114	frontPolys.push_back(poly);
3115	break;
3116	case Polygon3::BACK_SIDE:
3117	backPolys.push_back(poly);
3118	break;
3119	case Polygon3::SPLIT:
3120	backPolys.push_back(poly);
3121	frontPolys.push_back(poly);
3122	++ splits;
3123	break;
3124	default:
3125	Debug << "SHOULD NEVER COME HERE\n";
3126	break;
3127	}
3128	}
3129
3130	return splits;
3131	}
3132
3133
3134	int VspBspTree::CastLineSegment(const Vector3 &origin,
3135	const Vector3 &termination,
3136	vector<ViewCell *> &viewcells)
3137	{
3138	int hits = 0;
3139	stack<BspRayTraversalData> tStack;
3140
3141	float mint = 0.0f, maxt = 1.0f;
3142
3143	Intersectable::NewMail();
3144	ViewCell::NewMail();
3145
3146	Vector3 entp = origin;
3147	Vector3 extp = termination;
3148
3149	BspNode *node = mRoot;
3150	BspNode *farChild = NULL;
3151
3152	float t;
3153	const float thresh = 1e-6f; // matt: change this
3154
3155	while (1)
3156	{
3157	if (!node->IsLeaf())
3158	{
3159	BspInterior in = dynamic_cast<BspInterior >(node);
3160
3161	Plane3 splitPlane = in->GetPlane();
3162
3163	const int entSide = splitPlane.Side(entp, thresh);
3164	const int extSide = splitPlane.Side(extp, thresh);
3165
3166	if (entSide < 0)
3167	{
3168	node = in->GetBack();
3169
3170	// plane does not split ray => no far child
3171	if (extSide <= 0)
3172	continue;
3173
3174	farChild = in->GetFront(); // plane splits ray
3175	}
3176	else if (entSide > 0)
3177	{
3178	node = in->GetFront();
3179
3180	if (extSide >= 0) // plane does not split ray => no far child
3181	continue;
3182
3183	farChild = in->GetBack(); // plane splits ray
3184	}
3185	else // one of the ray end points is on the plane
3186	{ // NOTE: what to do if ray is coincident with plane?
3187	if (extSide < 0)
3188	node = in->GetBack();
3189	else //if (extSide > 0)
3190	node = in->GetFront();
3191	//else break; // coincident => count no intersections
3192
3193	continue; // no far child
3194	}
3195
3196	// push data for far child
3197	tStack.push(BspRayTraversalData(farChild, extp));
3198
3199	// find intersection of ray segment with plane
3200	extp = splitPlane.FindIntersection(origin, extp, &t);
3201	}
3202	else
3203	{
3204	// reached leaf => intersection with view cell
3205	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3206	ViewCell *viewCell;
3207
3208	if (0)
3209	viewCell = mViewCellsTree->GetActiveViewCell(leaf->GetViewCell());
3210	else
3211	viewCell = leaf->GetViewCell();
3212
3213	if (!viewCell->Mailed())
3214	{
3215	viewcells.push_back(viewCell);
3216	viewCell->Mail();
3217	++ hits;
3218	}
3219
3220	//-- fetch the next far child from the stack
3221	if (tStack.empty())
3222	break;
3223
3224	entp = extp;
3225
3226	const BspRayTraversalData &s = tStack.top();
3227
3228	node = s.mNode;
3229	extp = s.mExitPoint;
3230
3231	tStack.pop();
3232	}
3233	}
3234
3235	return hits;
3236	}
3237
3238
3239
3240
3241	int VspBspTree::TreeDistance(BspNode n1, BspNode n2) const
3242	{
3243	std::deque<BspNode *> path1;
3244	BspNode *p1 = n1;
3245
3246	// create path from node 1 to root
3247	while (p1)
3248	{
3249	if (p1 == n2) // second node on path
3250	return (int)path1.size();
3251
3252	path1.push_front(p1);
3253	p1 = p1->GetParent();
3254	}
3255
3256	int depth = n2->GetDepth();
3257	int d = depth;
3258
3259	BspNode *p2 = n2;
3260
3261	// compare with same depth
3262	while (1)
3263	{
3264	if ((d < (int)path1.size()) && (p2 == path1[d]))
3265	return (depth - d) + ((int)path1.size() - 1 - d);
3266
3267	-- d;
3268	p2 = p2->GetParent();
3269	}
3270
3271	return 0; // never come here
3272	}
3273
3274
3275	BspNode VspBspTree::CollapseTree(BspNode node, int &collapsed)
3276	{
3277	// TODO
3278	#if HAS_TO_BE_REDONE
3279	if (node->IsLeaf())
3280	return node;
3281
3282	BspInterior interior = dynamic_cast<BspInterior >(node);
3283
3284	BspNode *front = CollapseTree(interior->GetFront(), collapsed);
3285	BspNode *back = CollapseTree(interior->GetBack(), collapsed);
3286
3287	if (front->IsLeaf() && back->IsLeaf())
3288	{
3289	BspLeaf frontLeaf = dynamic_cast<BspLeaf >(front);
3290	BspLeaf backLeaf = dynamic_cast<BspLeaf >(back);
3291
3292	//-- collapse tree
3293	if (frontLeaf->GetViewCell() == backLeaf->GetViewCell())
3294	{
3295	BspViewCell *vc = frontLeaf->GetViewCell();
3296
3297	BspLeaf *leaf = new BspLeaf(interior->GetParent(), vc);
3298	leaf->SetTreeValid(frontLeaf->TreeValid());
3299
3300	// replace a link from node's parent
3301	if (leaf->GetParent())
3302	leaf->GetParent()->ReplaceChildLink(node, leaf);
3303	else
3304	mRoot = leaf;
3305
3306	++ collapsed;
3307	delete interior;
3308
3309	return leaf;
3310	}
3311	}
3312	#endif
3313	return node;
3314	}
3315
3316
3317	int VspBspTree::CollapseTree()
3318	{
3319	int collapsed = 0;
3320	//TODO
3321	#if HAS_TO_BE_REDONE
3322	(void)CollapseTree(mRoot, collapsed);
3323
3324	// revalidate leaves
3325	RepairViewCellsLeafLists();
3326	#endif
3327	return collapsed;
3328	}
3329
3330
3331	void VspBspTree::RepairViewCellsLeafLists()
3332	{
3333	// TODO
3334	#if HAS_TO_BE_REDONE
3335	// list not valid anymore => clear
3336	stack<BspNode *> nodeStack;
3337	nodeStack.push(mRoot);
3338
3339	ViewCell::NewMail();
3340
3341	while (!nodeStack.empty())
3342	{
3343	BspNode *node = nodeStack.top();
3344	nodeStack.pop();
3345
3346	if (node->IsLeaf())
3347	{
3348	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3349
3350	BspViewCell *viewCell = leaf->GetViewCell();
3351
3352	if (!viewCell->Mailed())
3353	{
3354	viewCell->mLeaves.clear();
3355	viewCell->Mail();
3356	}
3357
3358	viewCell->mLeaves.push_back(leaf);
3359
3360	}
3361	else
3362	{
3363	BspInterior interior = dynamic_cast<BspInterior >(node);
3364
3365	nodeStack.push(interior->GetFront());
3366	nodeStack.push(interior->GetBack());
3367	}
3368	}
3369	// TODO
3370	#endif
3371	}
3372
3373
3374	typedef pair<BspNode , BspNodeGeometry > bspNodePair;
3375
3376
3377	int VspBspTree::CastBeam(Beam &beam)
3378	{
3379	stack<bspNodePair> nodeStack;
3380	BspNodeGeometry *rgeom = new BspNodeGeometry();
3381	ConstructGeometry(mRoot, *rgeom);
3382
3383	nodeStack.push(bspNodePair(mRoot, rgeom));
3384
3385	ViewCell::NewMail();
3386
3387	while (!nodeStack.empty())
3388	{
3389	BspNode *node = nodeStack.top().first;
3390	BspNodeGeometry *geom = nodeStack.top().second;
3391	nodeStack.pop();
3392
3393	AxisAlignedBox3 box;
3394	geom->GetBoundingBox(box);
3395
3396	const int side = beam.ComputeIntersection(box);
3397
3398	switch (side)
3399	{
3400	case -1:
3401	CollectViewCells(node, true, beam.mViewCells, true);
3402	break;
3403	case 0:
3404
3405	if (node->IsLeaf())
3406	{
3407	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3408
3409	if (!leaf->GetViewCell()->Mailed() && leaf->TreeValid())
3410	{
3411	leaf->GetViewCell()->Mail();
3412	beam.mViewCells.push_back(leaf->GetViewCell());
3413	}
3414	}
3415	else
3416	{
3417	BspInterior interior = dynamic_cast<BspInterior >(node);
3418
3419	BspNode *first = interior->GetFront();
3420	BspNode *second = interior->GetBack();
3421
3422	BspNodeGeometry *firstGeom = new BspNodeGeometry();
3423	BspNodeGeometry *secondGeom = new BspNodeGeometry();
3424
3425	geom->SplitGeometry(*firstGeom,
3426	*secondGeom,
3427	interior->GetPlane(),
3428	mBox,
3429	//0.0000001f);
3430	mEpsilon);
3431
3432	// decide on the order of the nodes
3433	if (DotProd(beam.mPlanes[0].mNormal,
3434	interior->GetPlane().mNormal) > 0)
3435	{
3436	swap(first, second);
3437	swap(firstGeom, secondGeom);
3438	}
3439
3440	nodeStack.push(bspNodePair(first, firstGeom));
3441	nodeStack.push(bspNodePair(second, secondGeom));
3442	}
3443
3444	break;
3445	default:
3446	// default: cull
3447	break;
3448	}
3449
3450	DEL_PTR(geom);
3451
3452	}
3453
3454	return (int)beam.mViewCells.size();
3455	}
3456
3457
3458	void VspBspTree::SetViewCellsManager(ViewCellsManager *vcm)
3459	{
3460	mViewCellsManager = vcm;
3461	}
3462
3463
3464	int VspBspTree::CollectMergeCandidates(const vector<BspLeaf *> leaves,
3465	vector<MergeCandidate> &candidates)
3466	{
3467	BspLeaf::NewMail();
3468
3469	vector<BspLeaf *>::const_iterator it, it_end = leaves.end();
3470
3471	int numCandidates = 0;
3472
3473	// find merge candidates and push them into queue
3474	for (it = leaves.begin(); it != it_end; ++ it)
3475	{
3476	BspLeaf leaf = it;
3477
3478	// the same leaves must not be part of two merge candidates
3479	leaf->Mail();
3480
3481	vector<BspLeaf *> neighbors;
3482
3483	// appoximate neighbor search has slightl relaxed constraints
3484	if (1)
3485	FindNeighbors(leaf, neighbors, true);
3486	else
3487	FindApproximateNeighbors(leaf, neighbors, true);
3488
3489	vector<BspLeaf *>::const_iterator nit, nit_end = neighbors.end();
3490
3491	// TODO: test if at least one ray goes from one leaf to the other
3492	for (nit = neighbors.begin(); nit != nit_end; ++ nit)
3493	{
3494	if ((*nit)->GetViewCell() != leaf->GetViewCell())
3495	{
3496	MergeCandidate mc(leaf->GetViewCell(), (*nit)->GetViewCell());
3497
3498	// dont't merge view cells if they are empty and not front and back leaf of the same parent
3499	// in the tree?
3500	if (mEmptyViewCellsMergeAllowed \|\|
3501	!leaf->GetViewCell()->GetPvs().Empty() \|\|
3502	!(*nit)->GetViewCell()->GetPvs().Empty() \|\|
3503	leaf->IsSibling(*nit))
3504	{
3505	candidates.push_back(mc);
3506	}
3507
3508	++ numCandidates;
3509	if ((numCandidates % 1000) == 0)
3510	{
3511	cout << "collected " << numCandidates << " merge candidates" << endl;
3512	}
3513	}
3514	}
3515	}
3516
3517	Debug << "merge queue: " << (int)candidates.size() << endl;
3518	Debug << "leaves in queue: " << numCandidates << endl;
3519
3520
3521	return (int)leaves.size();
3522	}
3523
3524
3525	int VspBspTree::CollectMergeCandidates(const VssRayContainer &rays,
3526	vector<MergeCandidate> &candidates)
3527	{
3528	ViewCell::NewMail();
3529	long startTime = GetTime();
3530
3531	map<BspLeaf , vector<BspLeaf> > neighborMap;
3532	ViewCellContainer::const_iterator iit;
3533
3534	int numLeaves = 0;
3535
3536	BspLeaf::NewMail();
3537
3538	for (int i = 0; i < (int)rays.size(); ++ i)
3539	{
3540	VssRay *ray = rays[i];
3541
3542	// traverse leaves stored in the rays and compare and
3543	// merge consecutive leaves (i.e., the neighbors in the tree)
3544	if (ray->mViewCells.size() < 2)
3545	continue;
3546	//TODO viewcellhierarchy
3547	iit = ray->mViewCells.begin();
3548	BspViewCell bspVc = dynamic_cast<BspViewCell >(*(iit ++));
3549	BspLeaf *leaf = bspVc->mLeaf;
3550
3551	// traverse intersections
3552	// consecutive leaves are neighbors => add them to queue
3553	for (; iit != ray->mViewCells.end(); ++ iit)
3554	{
3555	// next pair
3556	BspLeaf *prevLeaf = leaf;
3557	bspVc = dynamic_cast<BspViewCell >(iit);
3558	leaf = bspVc->mLeaf;
3559
3560	// view space not valid or same view cell
3561	if (!leaf->TreeValid() \|\| !prevLeaf->TreeValid() \|\|
3562	(leaf->GetViewCell() == prevLeaf->GetViewCell()))
3563	continue;
3564
3565	vector<BspLeaf *> &neighbors = neighborMap[leaf];
3566
3567	bool found = false;
3568
3569	// both leaves inserted in queue already =>
3570	// look if double pair already exists
3571	if (leaf->Mailed() && prevLeaf->Mailed())
3572	{
3573	vector<BspLeaf *>::const_iterator it, it_end = neighbors.end();
3574
3575	for (it = neighbors.begin(); !found && (it != it_end); ++ it)
3576	if (*it == prevLeaf)
3577	found = true; // already in queue
3578	}
3579
3580	if (!found)
3581	{
3582	// this pair is not in map yet
3583	// => insert into the neighbor map and the queue
3584	neighbors.push_back(prevLeaf);
3585	neighborMap[prevLeaf].push_back(leaf);
3586
3587	leaf->Mail();
3588	prevLeaf->Mail();
3589
3590	MergeCandidate mc(leaf->GetViewCell(), prevLeaf->GetViewCell());
3591
3592	candidates.push_back(mc);
3593
3594	if (((int)candidates.size() % 1000) == 0)
3595	{
3596	cout << "collected " << (int)candidates.size() << " merge candidates" << endl;
3597	}
3598	}
3599	}
3600	}
3601
3602	Debug << "neighbormap size: " << (int)neighborMap.size() << endl;
3603	Debug << "merge queue: " << (int)candidates.size() << endl;
3604	Debug << "leaves in queue: " << numLeaves << endl;
3605
3606
3607	//-- collect the leaves which haven't been found by ray casting
3608	if (0)
3609	{
3610	cout << "finding additional merge candidates using geometry" << endl;
3611	vector<BspLeaf *> leaves;
3612	CollectLeaves(leaves, true);
3613	Debug << "found " << (int)leaves.size() << " new leaves" << endl << endl;
3614	CollectMergeCandidates(leaves, candidates);
3615	}
3616
3617	return numLeaves;
3618	}
3619
3620
3621
3622
3623	ViewCell *VspBspTree::GetViewCell(const Vector3 &point)
3624	{
3625	if (mRoot == NULL)
3626	return NULL;
3627
3628	stack<BspNode *> nodeStack;
3629	nodeStack.push(mRoot);
3630
3631	ViewCell *viewcell = NULL;
3632
3633	while (!nodeStack.empty()) {
3634	BspNode *node = nodeStack.top();
3635	nodeStack.pop();
3636
3637	if (node->IsLeaf()) {
3638	viewcell = dynamic_cast<BspLeaf *>(node)->GetViewCell();
3639	break;
3640	} else {
3641
3642	BspInterior interior = dynamic_cast<BspInterior >(node);
3643
3644	// random decision
3645	if (interior->GetPlane().Side(point) < 0)
3646	nodeStack.push(interior->GetBack());
3647	else
3648	nodeStack.push(interior->GetFront());
3649	}
3650	}
3651
3652	return viewcell;
3653	}
3654
3655
3656	bool VspBspTree::ViewPointValid(const Vector3 &viewPoint) const
3657	{
3658	BspNode *node = mRoot;
3659
3660	while (1)
3661	{
3662	// early exit
3663	if (node->TreeValid())
3664	return true;
3665
3666	if (node->IsLeaf())
3667	return false;
3668
3669	BspInterior in = dynamic_cast<BspInterior >(node);
3670
3671	if (in->GetPlane().Side(viewPoint) <= 0)
3672	{
3673	node = in->GetBack();
3674	}
3675	else
3676	{
3677	node = in->GetFront();
3678	}
3679	}
3680
3681	// should never come here
3682	return false;
3683	}
3684
3685
3686	void VspBspTree::PropagateUpValidity(BspNode *node)
3687	{
3688	const bool isValid = node->TreeValid();
3689
3690	// propagative up invalid flag until only invalid nodes exist over this node
3691	if (!isValid)
3692	{
3693	while (!node->IsRoot() && node->GetParent()->TreeValid())
3694	{
3695	node = node->GetParent();
3696	node->SetTreeValid(false);
3697	}
3698	}
3699	else
3700	{
3701	// propagative up valid flag until one of the subtrees is invalid
3702	while (!node->IsRoot() && !node->TreeValid())
3703	{
3704	node = node->GetParent();
3705	BspInterior interior = dynamic_cast<BspInterior >(node);
3706
3707	// the parent is valid iff both leaves are valid
3708	node->SetTreeValid(interior->GetBack()->TreeValid() &&
3709	interior->GetFront()->TreeValid());
3710	}
3711	}
3712	}
3713
3714
3715	bool VspBspTree::Export(ofstream &stream)
3716	{
3717	ExportNode(mRoot, stream);
3718
3719	return true;
3720	}
3721
3722
3723	void VspBspTree::ExportNode(BspNode *node, ofstream &stream)
3724	{
3725	if (node->IsLeaf())
3726	{
3727	BspLeaf leaf = dynamic_cast<BspLeaf >(node);
3728	ViewCell *viewCell = mViewCellsTree->GetActiveViewCell(leaf->GetViewCell());
3729
3730	int id = -1;
3731	if (viewCell != mOutOfBoundsCell)
3732	id = viewCell->GetId();
3733
3734	stream << "<Leaf viewCellId=\"" << id << "\" />" << endl;
3735	}
3736	else
3737	{
3738	BspInterior interior = dynamic_cast<BspInterior >(node);
3739
3740	Plane3 plane = interior->GetPlane();
3741	stream << "<Interior plane=\"" << plane.mNormal.x << " "
3742	<< plane.mNormal.y << " " << plane.mNormal.z << " "
3743	<< plane.mD << "\">" << endl;
3744
3745	ExportNode(interior->GetBack(), stream);
3746	ExportNode(interior->GetFront(), stream);
3747
3748	stream << "</Interior>" << endl;
3749	}
3750	}

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