Context Navigation

source: trunk/VUT/GtpVisibilityPreprocessor/src/VssPreprocessor.cpp @ 401

Revision 401, 8.0 KB checked in by bittner, 19 years ago (diff)
vsspreprocessor updates

Line
1	#include "SceneGraph.h"
2	#include "KdTree.h"
3	#include "VssPreprocessor.h"
4	#include "X3dExporter.h"
5	#include "Environment.h"
6	#include "MutualVisibility.h"
7	#include "Polygon3.h"
8	#include "ViewCell.h"
9	#include "VssRay.h"
10	#include "VssTree.h"
11
12	VssPreprocessor::VssPreprocessor():
13	mPass(0),
14	mVssRays()
15	{
16	// this should increase coherence of the samples
17	environment->GetIntValue("VssPreprocessor.samplesPerPass", mSamplesPerPass);
18	environment->GetIntValue("VssPreprocessor.totalSamples", mTotalSamples);
19	mStats.open("stats.log");
20	}
21
22	VssPreprocessor::~VssPreprocessor()
23	{
24	CLEAR_CONTAINER(mVssRays);
25	}
26
27	void
28	VssPreprocessor::SetupRay(Ray &ray,
29	const Vector3 &point,
30	const Vector3 &direction
31	)
32	{
33	ray.intersections.clear();
34	// do not store anything else then intersections at the ray
35	ray.Init(point, direction, Ray::LOCAL_RAY);
36	}
37
38	int
39	VssPreprocessor::CastRay(
40	Vector3 &viewPoint,
41	Vector3 &direction,
42	VssRayContainer &vssRays
43	)
44	{
45	int hits = 0;
46	static Ray ray;
47	AxisAlignedBox3 box = mKdTree->GetBox();
48
49	SetupRay(ray, viewPoint, direction);
50	// cast ray to KD tree to find intersection with other objects
51	Intersectable objectA, objectB;
52	Vector3 pointA, pointB;
53	float bsize = Magnitude(box.Size());
54	if (mKdTree->CastRay(ray)) {
55	objectA = ray.intersections[0].mObject;
56	pointA = ray.Extrap(ray.intersections[0].mT);
57	} else {
58	objectA = NULL;
59	// compute intersection with the scene bounding box
60	float tmin, tmax;
61	box.ComputeMinMaxT(ray, &tmin, &tmax);
62	if (tmax > bsize) {
63	// cerr<<"Warning: tmax > box size tmax="<<tmax<<" tmin="<<tmin<<" size="<<bsize<<endl;
64	// cerr<<"ray"<<ray<<endl;
65	}
66	pointA = ray.Extrap(tmax);
67
68	}
69
70	bool detectEmptyViewSpace = true;
71
72	if (detectEmptyViewSpace) {
73	SetupRay(ray, pointA, -direction);
74	} else
75	SetupRay(ray, viewPoint, -direction);
76
77
78	if (mKdTree->CastRay(ray)) {
79
80	objectB = ray.intersections[0].mObject;
81	pointB = ray.Extrap(ray.intersections[0].mT);
82
83	} else {
84	objectB = NULL;
85	float tmin, tmax;
86	box.ComputeMinMaxT(ray, &tmin, &tmax);
87	if (tmax > bsize) {
88	// cerr<<"Warning: tmax > box size tmax="<<tmax<<" tmin="<<tmin<<" size="<<bsize<<endl;
89	// cerr<<"ray"<<ray<<endl;
90	}
91
92	pointB = ray.Extrap(tmax);
93	}
94
95	VssRay *vssRay = NULL;
96
97	bool validSample = true;
98	if (detectEmptyViewSpace) {
99	if (Distance(pointA, pointB) <
100	Distance(viewPoint, pointA) + Distance(viewPoint, pointB) - Limits::Small) {
101	validSample = false;
102	}
103	}
104
105	if (validSample) {
106	if (objectA) {
107	vssRay = new VssRay(pointB,
108	pointA,
109	objectB,
110	objectA);
111	vssRays.push_back(vssRay);
112	hits ++;
113	}
114
115	if (objectB) {
116	vssRay = new VssRay(pointA,
117	pointB,
118	objectA,
119	objectB);
120	vssRays.push_back(vssRay);
121	hits ++;
122	}
123	}
124
125	return hits;
126	}
127
128
129	Vector3
130	VssPreprocessor::GetViewpoint(AxisAlignedBox3 *viewSpaceBox)
131	{
132	AxisAlignedBox3 box;
133
134	if (viewSpaceBox)
135	box =*viewSpaceBox;
136	else
137	box = mKdTree->GetBox();
138
139	// shrink the box in the y direction
140	return box.GetRandomPoint();
141	}
142
143	Vector3
144	VssPreprocessor::GetDirection(const Vector3 &viewpoint)
145	{
146	int i = RandomValue(0, mObjects.size()-1);
147	Intersectable *object = mObjects[i];
148	Vector3 point, normal;
149	object->GetRandomSurfacePoint(point, normal);
150	return point - viewpoint;
151	}
152
153	int
154	VssPreprocessor::RandomizedImportanceSampling(VssTree *vssTree,
155	const int desiredSamples)
156	{
157	float minRayContribution;
158	float maxRayContribution;
159	float avgRayContribution;
160
161	vssTree->GetRayContributionStatistics(minRayContribution,
162	maxRayContribution,
163	avgRayContribution);
164
165	cout<<
166	"#MIN_RAY_CONTRIB\n"<<minRayContribution<<endl<<
167	"#MAX_RAY_CONTRIB\n"<<maxRayContribution<<endl<<
168	"#AVG_RAY_CONTRIB\n"<<avgRayContribution<<endl;
169
170	float p = desiredSamples/(float)(avgRayContribution*vssTree->stat.Leaves());
171	SimpleRayContainer rays;
172	int num = vssTree->GenerateRays(p, rays);
173	cout<<"Generated "<<num<<" rays."<<endl;
174
175	VssRayContainer vssRays;
176
177	for (int i=0; i < rays.size(); i++)
178	CastRay(rays[i].mOrigin, rays[i].mDirection, vssRays);
179
180	vssTree->AddRays(vssRays);
181	return num;
182	}
183
184
185	bool
186	VssPreprocessor::ComputeVisibility()
187	{
188
189	mSceneGraph->CollectObjects(&mObjects);
190
191	long startTime = GetTime();
192
193	int totalSamples = 0;
194
195	AxisAlignedBox3 *viewSpaceBox = NULL;
196
197	AxisAlignedBox3 box = mKdTree->GetBox();
198
199
200	if (1)
201	box.Enlarge(box.Size()*-Vector3(0.45, 0.45, 0.45));
202	else {
203	// sample city like heights
204	box.SetMin(1, box.Min(1) + box.Size(1)*0.1);
205	box.SetMax(1, box.Min(1) + box.Size(1)*0.2);
206	}
207
208	bool useViewSpaceBox = false;
209	if (useViewSpaceBox)
210	viewSpaceBox = &box;
211
212	VssTree *vssTree = NULL;
213
214	while (totalSamples < mTotalSamples) {
215	int passContributingSamples = 0;
216	int passSampleContributions = 0;
217	int passSamples = 0;
218	int index = 0;
219
220	int sampleContributions;
221
222
223	for (int k=0; k < mSamplesPerPass; k++) {
224
225	Vector3 viewpoint = GetViewpoint(viewSpaceBox);
226	Vector3 direction = GetDirection(viewpoint);
227
228	sampleContributions = CastRay(viewpoint, direction, mVssRays);
229
230
231	//-- CORR matt: put block inside loop
232	if (sampleContributions) {
233	passContributingSamples ++;
234	passSampleContributions += sampleContributions;
235	}
236	passSamples++;
237	totalSamples++;
238	}
239
240	mPass++;
241
242	int pvsSize = 0;
243	float avgRayContrib = (passContributingSamples > 0) ?
244	passSampleContributions/(float)passContributingSamples : 0;
245
246	cout << "#Pass " << mPass << " : t = " << TimeDiff(startTime, GetTime())*1e-3 << "s" << endl;
247	cout << "#TotalSamples=" << totalSamples/1000
248	<< "k #SampleContributions=" << passSampleContributions << " ("
249	<< 100*passContributingSamples/(float)passSamples<<"%)" << " avgPVS="
250	<< pvsSize/(float)mObjects.size() << endl
251	<< "avg ray contrib=" << avgRayContrib << endl;
252
253	mStats <<
254	"#Pass\n" <<mPass<<endl<<
255	"#Time\n" << TimeDiff(startTime, GetTime())*1e-3 << endl<<
256	"#TotalSamples\n" << totalSamples<< endl<<
257	"#SampleContributions\n" << passSampleContributions << endl <<
258	"#PContributingSamples\n"<<100*passContributingSamples/(float)passSamples<<endl <<
259	"#AvgPVS\n"<< pvsSize/(float)mObjects.size() << endl <<
260	"#AvgRayContrib\n" << avgRayContrib << endl;
261
262
263
264
265	}
266
267	cout << "#totalPvsSize=" << mKdTree->CollectLeafPvs() << endl;
268	cout << "#totalRayStackSize=" << mVssRays.size() << endl <<flush;
269
270	cout<<"Exporting vss rays..."<<endl<<flush;
271
272	int exportRays = 10000;
273
274	if (exportRays) {
275	float prob = exportRays/(float)mVssRays.size();
276
277	Exporter *exporter = NULL;
278	exporter = Exporter::GetExporter("vss-rays.x3d");
279	exporter->SetWireframe();
280	exporter->ExportKdTree(*mKdTree);
281	if (viewSpaceBox) {
282	exporter->SetForcedMaterial(RgbColor(1,0,0));
283	exporter->ExportBox(*viewSpaceBox);
284	exporter->ResetForcedMaterial();
285	}
286	VssRayContainer rays;
287	for (int i=0; i < mVssRays.size(); i++)
288	if (RandomValue(0,1) < prob)
289	rays.push_back(mVssRays[i]);
290	exporter->ExportRays(rays, RgbColor(1, 0, 0));
291
292	delete exporter;
293	}
294	cout<<"done."<<endl<<flush;
295
296
297
298
299	vssTree = new VssTree;
300
301	vssTree->Construct(mVssRays, viewSpaceBox);
302
303	cout<<"VssTree root PVS size = "<<vssTree->GetRootPvsSize()<<endl;
304
305
306	int samples = 0;
307	for (int i=0; i < 50; i++) {
308	int num = 100000;
309	if (0) {
310	VssRayContainer vssRays;
311	for (int j=0; j < num; j++) {
312	Vector3 viewpoint = GetViewpoint(viewSpaceBox);
313	Vector3 direction = GetDirection(viewpoint);
314	CastRay(viewpoint, direction, vssRays);
315	}
316	vssTree->AddRays(vssRays);
317	} else {
318	num = RandomizedImportanceSampling(vssTree, num);
319	}
320	samples+=num;
321	float pvs = vssTree->GetAvgPvsSize();
322	cout<<samples<<" avgPVS ="<<pvs<<endl;
323	}
324
325	delete vssTree;
326
327	return true;
328	}
329

Note: See TracBrowser for help on using the repository browser.

Download in other formats: