WebSVN – gelsvn – Diff – /trunk/src/HMesh/quadric_simplify.cpp


#include <queue>
#include <iostream>
#include "quadric_simplify.h"
#include "smooth.h"
#include "HMesh/VertexCirculator.h"
#include "Geometry/QEM.h"
 
 
namespace HMesh
{
		using namespace CGLA;
		using namespace std;
		using namespace GEO;
		using namespace HMesh;
 
		namespace
		{
				/* We create a record for each halfedge where we can keep its time
					 stamp. If the time stamp on the halfedge record is bigger than
					 the stamp on the simplification record, we cannot use the 
					 simplification record (see below). */
				struct HalfEdgeRec
				{
						HalfEdgeIter he;
						int time_stamp;
						void halfedge_removed() {time_stamp = -1;}
						HalfEdgeRec(): time_stamp(0) {}
				};
 
				/* The simpliciation record contains information about a potential
					 edge contraction */
				struct SimplifyRec
				{
						Vec3d opt_pos;  // optimal vertex position
						int he_index;   // Index (into HalfEdgeRec vector) of edge
						                // we want to contract
						float err;      // Error associated with contraction
						int time_stamp; // Time stamp (see comment on HalfEdgeRec)
						int visits;     // Visits (number of times we considered this 
						                // record).
				};
 
				bool operator<(const SimplifyRec& s1, const SimplifyRec& s2)
				{
						return s1.err > s2.err;
				}
 
				class QuadricSimplifier
				{
						typedef priority_queue<SimplifyRec> SimplifyQueue;
						typedef vector<QEM> QEMVec;
						typedef vector<HalfEdgeRec> HalfEdgeVec;
 
						Manifold& m;
						HalfEdgeVec halfedge_vec;
						QEMVec qem_vec;
						SimplifyQueue sim_queue;
 
						/* Compute the error associated with contraction of he and the
							 optimal position of resulting vertex. */
						void push_simplify_rec(HalfEdgeIter he);
 
						/* Check whether the contraction is valid. See below for details*/
						bool check_consistency(HalfEdgeIter he, const Vec3d& opt_pos);
 
						/* Update the time stamp of a halfedge. A halfedge and its opp edge
							 may have different stamps. We choose a stamp that is greater
							 than either and assign to both.*/
						void update_time_stamp(HalfEdgeIter he)
								{
										int time_stamp = s_max(halfedge_vec[he->touched].time_stamp,
																					 halfedge_vec[he->opp->touched].time_stamp);
										time_stamp++;
										halfedge_vec[he->touched].time_stamp = time_stamp;
										halfedge_vec[he->opp->touched].time_stamp = time_stamp;
								}
 
						/* Update time stamps for all halfedges in one ring of vi */
						void update_onering_timestamp(VertexIter vi);
 
						/* Perform a collapse - if conditions are met. Returns 1 or 0 
							 accordingly. */
						int collapse(SimplifyRec& simplify_rec);
 
				public:
 
						/* Create a simplifier for a manifold */
						QuadricSimplifier(Manifold& _m): 
								m(_m), 
								halfedge_vec(m.no_halfedges()), 
								qem_vec(m.no_vertices()) 
								{
										// Enumerate vertices
										m.enumerate_vertices();
			
										// Enumerate halfedges
										m.enumerate_halfedges();
								}
	
						/* Simplify doing at most max_work contractions */
						void reduce(int max_work);
				};
 
				bool QuadricSimplifier::check_consistency(HalfEdgeIter he, 
																									const Vec3d& opt_pos)
				{
						VertexIter v0 = he->vert;
						VertexIter v1 = he->opp->vert;
						Vec3d p0(v0->pos);
 
						/* This test is inspired by Garland's Ph.D. thesis. We try
							 to detect whether flipped triangles will occur by sort of
							 ensuring that the new vertex is in the hull of the one rings
							 of the vertices at either end of the edge being contracted */
						
						for(VertexCirculator vc(v0); !vc.end(); ++vc)
						{
								HalfEdgeIter h = vc.get_halfedge();
								if(h->vert != v1 && h->next->vert != v1)
								{
										Vec3d pa(h->vert->pos);
										Vec3d pb(h->next->vert->pos);
										
										Vec3d dir = normalize(pb-pa);
 
										Vec3d n = p0 - pa;
										n = n - dir * dot(dir,n);
 
										if(dot(n,opt_pos - pa) <= 0)
												return false;
								}
						}
 
						/* Since the test above is not really enough, we also make sure 
							 that we do not introduce vertices of very high (>=10) or low 
							 (<=3) valency. Flipped faces seem to be always associated with
							 very irregular valencies. It seems to get rid of most problems
							 not fixed by the check above. */
							 
						if(valency(he->next->vert)<5)
								return false;
 
						if((valency(he->vert) + valency(he->opp->vert) ) > 13)
								return false;
 
						return true;
				}
 
 
				void QuadricSimplifier::push_simplify_rec(HalfEdgeIter he)
				{
						// Get QEM for both end points
						const QEM& Q1 = qem_vec[he->vert->touched];
						const QEM& Q2 = qem_vec[he->opp->vert->touched];
 
						QEM q = Q1;
						q += Q2;
 
						float err;
						Vec3d opt_pos(0);
 
 
						
						opt_pos = q.opt_pos(0.000001);
						err = q.error(opt_pos);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
						// Create SimplifyRec
						int he_index = he->touched;
						SimplifyRec simplify_rec;
						simplify_rec.opt_pos = opt_pos;
						simplify_rec.err = err;
						simplify_rec.he_index = he_index;
						simplify_rec.time_stamp = halfedge_vec[he->touched].time_stamp;
						simplify_rec.visits = 0;
						// push it.
						sim_queue.push(simplify_rec);
						
				}
		
 
				void QuadricSimplifier::update_onering_timestamp(VertexIter vi)
				{
						// For all emanating edges he
						for(VertexCirculator vc(vi);
								!vc.end(); ++vc)
						{
								HalfEdgeIter he = vc.get_halfedge();
								update_time_stamp(he);
						}
				}
 
				int QuadricSimplifier::collapse(SimplifyRec& simplify_rec)
				{
						int he_index = simplify_rec.he_index;
						HalfEdgeIter he = halfedge_vec[he_index].he;
 
						// Check the time stamp to verify that the simplification 
						// record is the newest. If the halfedge has been removed
						// the time stamp is -1 and the comparison will also fail.
						if(halfedge_vec[he_index].time_stamp == simplify_rec.time_stamp)
						{
								VertexIter v = he->opp->vert;
								VertexIter n = he->vert;
 
								// If the edge is, in fact, collapsible
								if(m.collapse_precond(he))
								{
 										// If our consistency checks pass, we are relatively
 										// sure that the contraction does not lead to a face flip.
										if(check_consistency(he, simplify_rec.opt_pos) && 
											 check_consistency(he->opp, simplify_rec.opt_pos))
										{
 
												//cout << simplify_rec.err << " " << &(*he->vert) << endl;
												// Get QEM for both end points
												const QEM& Q1 = qem_vec[he->vert->touched];
												const QEM& Q2 = qem_vec[he->opp->vert->touched];
												
												// Compute Q_new = Q_1 + Q_2
												QEM q = Q1;
												q += Q2;
												
												// Mark all halfedges that will be removed as dead
												halfedge_vec[he->touched].halfedge_removed();
												halfedge_vec[he->opp->touched].halfedge_removed();
						
												if(he->next->next->next == he)
												{
														halfedge_vec[he->next->touched].halfedge_removed();
														halfedge_vec[he->next->next->touched].halfedge_removed();
												}
												if(he->opp->next->next->next == he->opp)
												{
														halfedge_vec[he->opp->next->touched].halfedge_removed();
														halfedge_vec[he->opp->next->next->touched].halfedge_removed();
												}
												
												// Do collapse
												m.collapse_halfedge(he,false);
												n->pos = Vec3f(simplify_rec.opt_pos);
												qem_vec[n->touched] = q;
												
												update_onering_timestamp(n);
												return 1;
										}
								}
								// If we are here, the collapse was not allowed. If we have
								// seen this simplify record less than 100 times, we try to
								// increase the error and store the record again. Maybe some
								// other contractions will make it more digestible later.
								if(simplify_rec.visits < 10)
								{
										simplify_rec.err += 5*simplify_rec.err + 1e-10;
										++simplify_rec.visits;
										sim_queue.push(simplify_rec);
								}
						}
						// Ok the time stamp did not match. Create a new record.
						else if(halfedge_vec[he_index].time_stamp != -1)
								push_simplify_rec(he);
 
						return 0;
				}
 
				void QuadricSimplifier::reduce(int max_work)
				{
						// Set t = 0 for all halfedges
						int i=0;
						for(HalfEdgeIter he = m.halfedges_begin();
								he != m.halfedges_end(); ++he, ++i)
								halfedge_vec[i].he = he;
 
						cout << "Computing quadrics" << endl;
		
						// For all vertices, compute quadric and store in qem_vec
						for(VertexIter vi=m.vertices_begin(); vi != m.vertices_end(); ++vi)
						{
								Vec3d p(vi->pos);
								QEM q;
								for(VertexCirculator vc(vi); !vc.end(); ++vc)
								{
										FaceIter f = vc.get_face();
										if(f != NULL_FACE_ITER)
										{
												Vec3d n(normal(f));
												double a = area(f);
												q += QEM(p, n, a / 3.0);
										}
								}
								qem_vec[vi->touched] = q;
						}
						cout << "Pushing initial halfedges" << endl;
 
						for(HalfEdgeIter he = m.halfedges_begin();
								he != m.halfedges_end(); ++he)
								// For all halfedges, 
						{
								if(halfedge_vec[he->touched].time_stamp == 0)
								{
										update_time_stamp(he);
										push_simplify_rec(he);
								}
						}
 
						cout << "Simplify" << endl;
 
						int work = 0;
						while(!sim_queue.empty() && work < max_work)
						{
								SimplifyRec simplify_record = sim_queue.top();
								sim_queue.pop();
 
								work += collapse(simplify_record);
								if((work % 100) == 0)
								{
										cout << "work = " << work << endl;
										cout << "sim Q size = " << sim_queue.size() << endl;
								}
						}
				}
		}
 
		void quadric_simplify(Manifold& m, int max_work)
		{
				srand(1210);
				QuadricSimplifier qsim(m);
				qsim.reduce(max_work);
		}
 
}
 

Rev 222	Rev 315
1	`#include <queue>`	1	`#include <queue>`
2	`#include <iostream>`	2	`#include <iostream>`
3	`#include "quadric_simplify.h"`	3	`#include "quadric_simplify.h"`
4	`#include "smooth.h"`	4	`#include "smooth.h"`
5	`#include "HMesh/VertexCirculator.h"`	5	`#include "HMesh/VertexCirculator.h"`
6	`#include "Geometry/QEM.h"`	6	`#include "Geometry/QEM.h"`
7		7
8		8
9	`namespace HMesh`	9	`namespace HMesh`
10	`{`	10	`{`
11	`using namespace CGLA;`	11	`using namespace CGLA;`
12	`using namespace std;`	12	`using namespace std;`
13	`using namespace GEO;`	13	`using namespace GEO;`
14	`using namespace HMesh;`	14	`using namespace HMesh;`
15		15
16	`namespace`	16	`namespace`
17	`{`	17	`{`
18	`/* We create a record for each halfedge where we can keep its time`	18	`/* We create a record for each halfedge where we can keep its time`
19	`stamp. If the time stamp on the halfedge record is bigger than`	19	`stamp. If the time stamp on the halfedge record is bigger than`
20	`the stamp on the simplification record, we cannot use the`	20	`the stamp on the simplification record, we cannot use the`
21	`simplification record (see below). */`	21	`simplification record (see below). */`
22	`struct HalfEdgeRec`	22	`struct HalfEdgeRec`
23	`{`	23	`{`
24	`HalfEdgeIter he;`	24	`HalfEdgeIter he;`
25	`int time_stamp;`	25	`int time_stamp;`
26	`void halfedge_removed() {time_stamp = -1;}`	26	`void halfedge_removed() {time_stamp = -1;}`
27	`HalfEdgeRec(): time_stamp(0) {}`	27	`HalfEdgeRec(): time_stamp(0) {}`
28	`};`	28	`};`
29		29
30	`/* The simpliciation record contains information about a potential`	30	`/* The simpliciation record contains information about a potential`
31	`edge contraction */`	31	`edge contraction */`
32	`struct SimplifyRec`	32	`struct SimplifyRec`
33	`{`	33	`{`
34	`Vec3d opt_pos; // optimal vertex position`	34	`Vec3d opt_pos; // optimal vertex position`
35	`int he_index; // Index (into HalfEdgeRec vector) of edge`	35	`int he_index; // Index (into HalfEdgeRec vector) of edge`
36	`// we want to contract`	36	`// we want to contract`
37	`float err; // Error associated with contraction`	37	`float err; // Error associated with contraction`
38	`int time_stamp; // Time stamp (see comment on HalfEdgeRec)`	38	`int time_stamp; // Time stamp (see comment on HalfEdgeRec)`
39	`int visits; // Visits (number of times we considered this`	39	`int visits; // Visits (number of times we considered this`
40	`// record).`	40	`// record).`
41	`};`	41	`};`
42		42
43	`bool operator<(const SimplifyRec& s1, const SimplifyRec& s2)`	43	`bool operator<(const SimplifyRec& s1, const SimplifyRec& s2)`
44	`{`	44	`{`
45	`return s1.err > s2.err;`	45	`return s1.err > s2.err;`
46	`}`	46	`}`
47		47
48	`class QuadricSimplifier`	48	`class QuadricSimplifier`
49	`{`	49	`{`
50	`typedef priority_queue<SimplifyRec> SimplifyQueue;`	50	`typedef priority_queue<SimplifyRec> SimplifyQueue;`
51	`typedef vector<QEM> QEMVec;`	51	`typedef vector<QEM> QEMVec;`
52	`typedef vector<HalfEdgeRec> HalfEdgeVec;`	52	`typedef vector<HalfEdgeRec> HalfEdgeVec;`
53		53
54	`Manifold& m;`	54	`Manifold& m;`
55	`HalfEdgeVec halfedge_vec;`	55	`HalfEdgeVec halfedge_vec;`
56	`QEMVec qem_vec;`	56	`QEMVec qem_vec;`
57	`SimplifyQueue sim_queue;`	57	`SimplifyQueue sim_queue;`
58		58
59	`/* Compute the error associated with contraction of he and the`	59	`/* Compute the error associated with contraction of he and the`
60	`optimal position of resulting vertex. */`	60	`optimal position of resulting vertex. */`
61	`void push_simplify_rec(HalfEdgeIter he);`	61	`void push_simplify_rec(HalfEdgeIter he);`
62		62
63	`/* Check whether the contraction is valid. See below for details*/`	63	`/* Check whether the contraction is valid. See below for details*/`
64	`bool check_consistency(HalfEdgeIter he, const Vec3d& opt_pos);`	64	`bool check_consistency(HalfEdgeIter he, const Vec3d& opt_pos);`
65		65
66	`/* Update the time stamp of a halfedge. A halfedge and its opp edge`	66	`/* Update the time stamp of a halfedge. A halfedge and its opp edge`
67	`may have different stamps. We choose a stamp that is greater`	67	`may have different stamps. We choose a stamp that is greater`
68	`than either and assign to both.*/`	68	`than either and assign to both.*/`
69	`void update_time_stamp(HalfEdgeIter he)`	69	`void update_time_stamp(HalfEdgeIter he)`
70	`{`	70	`{`
71	`int time_stamp = s_max(halfedge_vec[he->touched].time_stamp,`	71	`int time_stamp = s_max(halfedge_vec[he->touched].time_stamp,`
72	`halfedge_vec[he->opp->touched].time_stamp);`	72	`halfedge_vec[he->opp->touched].time_stamp);`
73	`time_stamp++;`	73	`time_stamp++;`
74	`halfedge_vec[he->touched].time_stamp = time_stamp;`	74	`halfedge_vec[he->touched].time_stamp = time_stamp;`
75	`halfedge_vec[he->opp->touched].time_stamp = time_stamp;`	75	`halfedge_vec[he->opp->touched].time_stamp = time_stamp;`
76	`}`	76	`}`
77		77
78	`/* Update time stamps for all halfedges in one ring of vi */`	78	`/* Update time stamps for all halfedges in one ring of vi */`
79	`void update_onering_timestamp(VertexIter vi);`	79	`void update_onering_timestamp(VertexIter vi);`
80		80
81	`/* Perform a collapse - if conditions are met. Returns 1 or 0`	81	`/* Perform a collapse - if conditions are met. Returns 1 or 0`
82	`accordingly. */`	82	`accordingly. */`
83	`int collapse(SimplifyRec& simplify_rec);`	83	`int collapse(SimplifyRec& simplify_rec);`
84		84
85	`public:`	85	`public:`
86		86
87	`/* Create a simplifier for a manifold */`	87	`/* Create a simplifier for a manifold */`
88	`QuadricSimplifier(Manifold& _m):`	88	`QuadricSimplifier(Manifold& _m):`
89	`m(_m),`	89	`m(_m),`
90	`halfedge_vec(m.no_halfedges()),`	90	`halfedge_vec(m.no_halfedges()),`
91	`qem_vec(m.no_vertices())`	91	`qem_vec(m.no_vertices())`
92	`{`	92	`{`
93	`// Enumerate vertices`	93	`// Enumerate vertices`
94	`m.enumerate_vertices();`	94	`m.enumerate_vertices();`
95		95
96	`// Enumerate halfedges`	96	`// Enumerate halfedges`
97	`m.enumerate_halfedges();`	97	`m.enumerate_halfedges();`
98	`}`	98	`}`
99		99
100	`/* Simplify doing at most max_work contractions */`	100	`/* Simplify doing at most max_work contractions */`
101	`void reduce(int max_work);`	101	`void reduce(int max_work);`
102	`};`	102	`};`
103		103
104	`bool QuadricSimplifier::check_consistency(HalfEdgeIter he,`	104	`bool QuadricSimplifier::check_consistency(HalfEdgeIter he,`
105	`const Vec3d& opt_pos)`	105	`const Vec3d& opt_pos)`
106	`{`	106	`{`
107	`VertexIter v0 = he->vert;`	107	`VertexIter v0 = he->vert;`
108	`VertexIter v1 = he->opp->vert;`	108	`VertexIter v1 = he->opp->vert;`
109	`Vec3d p0(v0->pos);`	109	`Vec3d p0(v0->pos);`
110		110
111	`/* This test is inspired by Garland's Ph.D. thesis. We try`	111	`/* This test is inspired by Garland's Ph.D. thesis. We try`
112	`to detect whether flipped triangles will occur by sort of`	112	`to detect whether flipped triangles will occur by sort of`
113	`ensuring that the new vertex is in the hull of the one rings`	113	`ensuring that the new vertex is in the hull of the one rings`
114	`of the vertices at either end of the edge being contracted */`	114	`of the vertices at either end of the edge being contracted */`
115		115
116	`for(VertexCirculator vc(v0); !vc.end(); ++vc)`	116	`for(VertexCirculator vc(v0); !vc.end(); ++vc)`
117	`{`	117	`{`
118	`HalfEdgeIter h = vc.get_halfedge();`	118	`HalfEdgeIter h = vc.get_halfedge();`
119	`if(h->vert != v1 && h->next->vert != v1)`	119	`if(h->vert != v1 && h->next->vert != v1)`
120	`{`	120	`{`
121	`Vec3d pa(h->vert->pos);`	121	`Vec3d pa(h->vert->pos);`
122	`Vec3d pb(h->next->vert->pos);`	122	`Vec3d pb(h->next->vert->pos);`
123		123
124	`Vec3d dir = normalize(pb-pa);`	124	`Vec3d dir = normalize(pb-pa);`
125		125
126	`Vec3d n = p0 - pa;`	126	`Vec3d n = p0 - pa;`
127	`n = n - dir * dot(dir,n);`	127	`n = n - dir * dot(dir,n);`
128		128
129	`if(dot(n,opt_pos - pa) <= 0)`	129	`if(dot(n,opt_pos - pa) <= 0)`
130	`return false;`	130	`return false;`
131	`}`	131	`}`
132	`}`	132	`}`
133		133
134	`/* Since the test above is not really enough, we also make sure`	134	`/* Since the test above is not really enough, we also make sure`
135	`that we do not introduce vertices of very high (>=10) or low`	135	`that we do not introduce vertices of very high (>=10) or low`
136	`(<=3) valency. Flipped faces seem to be always associated with`	136	`(<=3) valency. Flipped faces seem to be always associated with`
137	`very irregular valencies. It seems to get rid of most problems`	137	`very irregular valencies. It seems to get rid of most problems`
138	`not fixed by the check above. */`	138	`not fixed by the check above. */`
139		139
140	`if(valency(he->next->vert)<5)`	140	`if(valency(he->next->vert)<5)`
141	`return false;`	141	`return false;`
142		142
143	`if((valency(he->vert) + valency(he->opp->vert) ) > 13)`	143	`if((valency(he->vert) + valency(he->opp->vert) ) > 13)`
144	`return false;`	144	`return false;`
145		145
146	`return true;`	146	`return true;`
147	`}`	147	`}`
148		148
149		149
150	`void QuadricSimplifier::push_simplify_rec(HalfEdgeIter he)`	150	`void QuadricSimplifier::push_simplify_rec(HalfEdgeIter he)`
151	`{`	151	`{`
152	`// Get QEM for both end points`	152	`// Get QEM for both end points`
153	`const QEM& Q1 = qem_vec[he->vert->touched];`	153	`const QEM& Q1 = qem_vec[he->vert->touched];`
154	`const QEM& Q2 = qem_vec[he->opp->vert->touched];`	154	`const QEM& Q2 = qem_vec[he->opp->vert->touched];`
155		155
156	`QEM q = Q1;`	156	`QEM q = Q1;`
157	`q += Q2;`	157	`q += Q2;`
158		158
159	`float err;`	159	`float err;`
160	`Vec3d opt_pos(0);`	160	`Vec3d opt_pos(0);`
161		-
162	`// if (q.determinant()>= 1e-30)`	-
163	`{`	161
164	`opt_pos = q.opt_pos(0.001);`	162	`opt_pos = q.opt_pos(0.000001);`
165	`err = q.error(opt_pos);`	163	`err = q.error(opt_pos);`
166	`}`	-
167	`// else`	-
168	`// {`	-
169	`// // To see the effectivenes of the scheme, we can create`	-
170	`// // Random errors for comparison. Uncomment to use:`	-
171	`// // float e0 = time_stamp + rand()/float(RAND_MAX);//q.error(v0);`	-
172	`// // float e1 = time_stamp + rand()/float(RAND_MAX);//q.error(v1);`	-
173		-
174	`// Vec3d v0(he->vert->pos);`	-
175	`// Vec3d v1(he->opp->vert->pos);`	-
176	`// float e0 = q.error(v0);`	-
177	`// float e1 = q.error(v1);`	-
178		-
179	`// if(e0 < e1)`	-
180	`// {`	-
181	`// err = e0;`	-
182	`// opt_pos = v0;`	-
183	`// }`	-
184	`// else`	-
185	`// {`	-
186	`// err = e1;`	-
187	`// opt_pos = v1;`	-
188	`// }`	-
189	`// }`	-
190		164
191	`// Create SimplifyRec`	165	`// Create SimplifyRec`
192	`int he_index = he->touched;`	166	`int he_index = he->touched;`
193	`SimplifyRec simplify_rec;`	167	`SimplifyRec simplify_rec;`
194	`simplify_rec.opt_pos = opt_pos;`	168	`simplify_rec.opt_pos = opt_pos;`
195	`simplify_rec.err = err;`	169	`simplify_rec.err = err;`
196	`simplify_rec.he_index = he_index;`	170	`simplify_rec.he_index = he_index;`
197	`simplify_rec.time_stamp = halfedge_vec[he->touched].time_stamp;`	171	`simplify_rec.time_stamp = halfedge_vec[he->touched].time_stamp;`
198	`simplify_rec.visits = 0;`	172	`simplify_rec.visits = 0;`
199	`// push it.`	173	`// push it.`
200	`sim_queue.push(simplify_rec);`	174	`sim_queue.push(simplify_rec);`
201		175
202	`}`	176	`}`
203		177
204		178
205	`void QuadricSimplifier::update_onering_timestamp(VertexIter vi)`	179	`void QuadricSimplifier::update_onering_timestamp(VertexIter vi)`
206	`{`	180	`{`
207	`// For all emanating edges he`	181	`// For all emanating edges he`
208	`for(VertexCirculator vc(vi);`	182	`for(VertexCirculator vc(vi);`
209	`!vc.end(); ++vc)`	183	`!vc.end(); ++vc)`
210	`{`	184	`{`
211	`HalfEdgeIter he = vc.get_halfedge();`	185	`HalfEdgeIter he = vc.get_halfedge();`
212	`update_time_stamp(he);`	186	`update_time_stamp(he);`
213	`}`	187	`}`
214	`}`	188	`}`
215		189
216	`int QuadricSimplifier::collapse(SimplifyRec& simplify_rec)`	190	`int QuadricSimplifier::collapse(SimplifyRec& simplify_rec)`
217	`{`	191	`{`
218	`int he_index = simplify_rec.he_index;`	192	`int he_index = simplify_rec.he_index;`
219	`HalfEdgeIter he = halfedge_vec[he_index].he;`	193	`HalfEdgeIter he = halfedge_vec[he_index].he;`
220		194
221	`// Check the time stamp to verify that the simplification`	195	`// Check the time stamp to verify that the simplification`
222	`// record is the newest. If the halfedge has been removed`	196	`// record is the newest. If the halfedge has been removed`
223	`// the time stamp is -1 and the comparison will also fail.`	197	`// the time stamp is -1 and the comparison will also fail.`
224	`if(halfedge_vec[he_index].time_stamp == simplify_rec.time_stamp)`	198	`if(halfedge_vec[he_index].time_stamp == simplify_rec.time_stamp)`
225	`{`	199	`{`
226	`VertexIter v = he->opp->vert;`	200	`VertexIter v = he->opp->vert;`
227	`VertexIter n = he->vert;`	201	`VertexIter n = he->vert;`
228		202
229	`// If the edge is, in fact, collapsible`	203	`// If the edge is, in fact, collapsible`
230	`if(m.collapse_precond(he))`	204	`if(m.collapse_precond(he))`
231	`{`	205	`{`
232	`// If our consistency checks pass, we are relatively`	206	`// If our consistency checks pass, we are relatively`
233	`// sure that the contraction does not lead to a face flip.`	207	`// sure that the contraction does not lead to a face flip.`
234	`if(check_consistency(he, simplify_rec.opt_pos) &&`	208	`if(check_consistency(he, simplify_rec.opt_pos) &&`
235	`check_consistency(he->opp, simplify_rec.opt_pos))`	209	`check_consistency(he->opp, simplify_rec.opt_pos))`
236	`{`	210	`{`
237		211
238	`//cout << simplify_rec.err << " " << &(*he->vert) << endl;`	212	`//cout << simplify_rec.err << " " << &(*he->vert) << endl;`
239	`// Get QEM for both end points`	213	`// Get QEM for both end points`
240	`const QEM& Q1 = qem_vec[he->vert->touched];`	214	`const QEM& Q1 = qem_vec[he->vert->touched];`
241	`const QEM& Q2 = qem_vec[he->opp->vert->touched];`	215	`const QEM& Q2 = qem_vec[he->opp->vert->touched];`
242		216
243	`// Compute Q_new = Q_1 + Q_2`	217	`// Compute Q_new = Q_1 + Q_2`
244	`QEM q = Q1;`	218	`QEM q = Q1;`
245	`q += Q2;`	219	`q += Q2;`
246		220
247	`// Mark all halfedges that will be removed as dead`	221	`// Mark all halfedges that will be removed as dead`
248	`halfedge_vec[he->touched].halfedge_removed();`	222	`halfedge_vec[he->touched].halfedge_removed();`
249	`halfedge_vec[he->opp->touched].halfedge_removed();`	223	`halfedge_vec[he->opp->touched].halfedge_removed();`
250		224
251	`if(he->next->next->next == he)`	225	`if(he->next->next->next == he)`
252	`{`	226	`{`
253	`halfedge_vec[he->next->touched].halfedge_removed();`	227	`halfedge_vec[he->next->touched].halfedge_removed();`
254	`halfedge_vec[he->next->next->touched].halfedge_removed();`	228	`halfedge_vec[he->next->next->touched].halfedge_removed();`
255	`}`	229	`}`
256	`if(he->opp->next->next->next == he->opp)`	230	`if(he->opp->next->next->next == he->opp)`
257	`{`	231	`{`
258	`halfedge_vec[he->opp->next->touched].halfedge_removed();`	232	`halfedge_vec[he->opp->next->touched].halfedge_removed();`
259	`halfedge_vec[he->opp->next->next->touched].halfedge_removed();`	233	`halfedge_vec[he->opp->next->next->touched].halfedge_removed();`
260	`}`	234	`}`
261		235
262	`// Do collapse`	236	`// Do collapse`
263	`m.collapse_halfedge(he,false);`	237	`m.collapse_halfedge(he,false);`
264	`n->pos = Vec3f(simplify_rec.opt_pos);`	238	`n->pos = Vec3f(simplify_rec.opt_pos);`
265	`qem_vec[n->touched] = q;`	239	`qem_vec[n->touched] = q;`
266		240
267	`update_onering_timestamp(n);`	241	`update_onering_timestamp(n);`
268	`return 1;`	242	`return 1;`
269	`}`	243	`}`
270	`}`	244	`}`
271	`// If we are here, the collapse was not allowed. If we have`	245	`// If we are here, the collapse was not allowed. If we have`
272	`// seen this simplify record less than 100 times, we try to`	246	`// seen this simplify record less than 100 times, we try to`
273	`// increase the error and store the record again. Maybe some`	247	`// increase the error and store the record again. Maybe some`
274	`// other contractions will make it more digestible later.`	248	`// other contractions will make it more digestible later.`
275	`if(simplify_rec.visits < 10)`	249	`if(simplify_rec.visits < 10)`
276	`{`	250	`{`
277	`simplify_rec.err += 5*simplify_rec.err + 1e-10;`	251	`simplify_rec.err += 5*simplify_rec.err + 1e-10;`
278	`++simplify_rec.visits;`	252	`++simplify_rec.visits;`
279	`sim_queue.push(simplify_rec);`	253	`sim_queue.push(simplify_rec);`
280	`}`	254	`}`
281	`}`	255	`}`
282	`// Ok the time stamp did not match. Create a new record.`	256	`// Ok the time stamp did not match. Create a new record.`
283	`else if(halfedge_vec[he_index].time_stamp != -1)`	257	`else if(halfedge_vec[he_index].time_stamp != -1)`
284	`push_simplify_rec(he);`	258	`push_simplify_rec(he);`
285		259
286	`return 0;`	260	`return 0;`
287	`}`	261	`}`
288		262
289	`void QuadricSimplifier::reduce(int max_work)`	263	`void QuadricSimplifier::reduce(int max_work)`
290	`{`	264	`{`
291	`// Set t = 0 for all halfedges`	265	`// Set t = 0 for all halfedges`
292	`int i=0;`	266	`int i=0;`
293	`for(HalfEdgeIter he = m.halfedges_begin();`	267	`for(HalfEdgeIter he = m.halfedges_begin();`
294	`he != m.halfedges_end(); ++he, ++i)`	268	`he != m.halfedges_end(); ++he, ++i)`
295	`halfedge_vec[i].he = he;`	269	`halfedge_vec[i].he = he;`
296		270
297	`cout << "Computing quadrics" << endl;`	271	`cout << "Computing quadrics" << endl;`
298		272
299	`// For all vertices, compute quadric and store in qem_vec`	273	`// For all vertices, compute quadric and store in qem_vec`
300	`for(VertexIter vi=m.vertices_begin(); vi != m.vertices_end(); ++vi)`	274	`for(VertexIter vi=m.vertices_begin(); vi != m.vertices_end(); ++vi)`
301	`{`	275	`{`
302	`Vec3d p(vi->pos);`	276	`Vec3d p(vi->pos);`
303	`QEM q;`	277	`QEM q;`
304	`for(VertexCirculator vc(vi); !vc.end(); ++vc)`	278	`for(VertexCirculator vc(vi); !vc.end(); ++vc)`
305	`{`	279	`{`
306	`FaceIter f = vc.get_face();`	280	`FaceIter f = vc.get_face();`
307	`if(f != NULL_FACE_ITER)`	281	`if(f != NULL_FACE_ITER)`
308	`{`	282	`{`
309	`Vec3d n(normal(f));`	283	`Vec3d n(normal(f));`
310	`double a = area(f);`	284	`double a = area(f);`
311	`q += QEM(p, n, a / 3.0);`	285	`q += QEM(p, n, a / 3.0);`
312	`}`	286	`}`
313	`}`	287	`}`
314	`qem_vec[vi->touched] = q;`	288	`qem_vec[vi->touched] = q;`
315	`}`	289	`}`
316	`cout << "Pushing initial halfedges" << endl;`	290	`cout << "Pushing initial halfedges" << endl;`
317		291
318	`for(HalfEdgeIter he = m.halfedges_begin();`	292	`for(HalfEdgeIter he = m.halfedges_begin();`
319	`he != m.halfedges_end(); ++he)`	293	`he != m.halfedges_end(); ++he)`
320	`// For all halfedges,`	294	`// For all halfedges,`
321	`{`	295	`{`
322	`if(halfedge_vec[he->touched].time_stamp == 0)`	296	`if(halfedge_vec[he->touched].time_stamp == 0)`
323	`{`	297	`{`
324	`update_time_stamp(he);`	298	`update_time_stamp(he);`
325	`push_simplify_rec(he);`	299	`push_simplify_rec(he);`
326	`}`	300	`}`
327	`}`	301	`}`
328		302
329	`cout << "Simplify" << endl;`	303	`cout << "Simplify" << endl;`
330		304
331	`int work = 0;`	305	`int work = 0;`
332	`while(!sim_queue.empty() && work < max_work)`	306	`while(!sim_queue.empty() && work < max_work)`
333	`{`	307	`{`
334	`SimplifyRec simplify_record = sim_queue.top();`	308	`SimplifyRec simplify_record = sim_queue.top();`
335	`sim_queue.pop();`	309	`sim_queue.pop();`
336		310
337	`work += collapse(simplify_record);`	311	`work += collapse(simplify_record);`
338	`if((work % 100) == 0)`	312	`if((work % 100) == 0)`
339	`{`	313	`{`
340	`cout << "work = " << work << endl;`	314	`cout << "work = " << work << endl;`
341	`cout << "sim Q size = " << sim_queue.size() << endl;`	315	`cout << "sim Q size = " << sim_queue.size() << endl;`
342	`}`	316	`}`
343	`}`	317	`}`
344	`}`	318	`}`
345	`}`	319	`}`
346		320
347	`void quadric_simplify(Manifold& m, int max_work)`	321	`void quadric_simplify(Manifold& m, int max_work)`
348	`{`	322	`{`
349	`srand(1210);`	323	`srand(1210);`
350	`QuadricSimplifier qsim(m);`	324	`QuadricSimplifier qsim(m);`
351	`qsim.reduce(max_work);`	325	`qsim.reduce(max_work);`
352	`}`	326	`}`
353		327
354	`}`	328	`}`
355		329

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(root)/trunk/src/HMesh/quadric_simplify.cpp – Rev 222 → 315