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source: trunk/VUT/GtpVisibilityPreprocessor/src/VspBspTree.cpp @ 605

Revision 605, 71.9 KB checked in by mattausch, 19 years ago (diff)

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

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