1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/**************************************************************************
* *
* Regina - A Normal Surface Theory Calculator *
* Computational Engine *
* *
* Copyright (c) 1999-2008, Ben Burton *
* For further details contact Ben Burton (bab@debian.org). *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of the GNU General Public License as *
* published by the Free Software Foundation; either version 2 of the *
* License, or (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, but *
* WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
* General Public License for more details. *
* *
* You should have received a copy of the GNU General Public *
* License along with this program; if not, write to the Free *
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, *
* MA 02110-1301, USA. *
* *
**************************************************************************/
/* end stub */
#include "surfaces/nnormalsurface.h"
#include "surfaces/ndisc.h"
namespace regina {
std::ostream& operator << (std::ostream& out, const NDiscSpec& spec) {
out << '(' << spec.tetIndex << ", " << spec.type << ", "
<< spec.number << ')';
return out;
}
bool numberDiscsAwayFromVertex(int discType, int vertex) {
if (discType < 4)
return (vertex == discType);
return (vertex == 0 || vertex ==
vertexSplitPartner[(discType - 1) % 3][0]);
}
bool discOrientationFollowsEdge(int discType, int vertex, int edgeStart,
int edgeEnd) {
NPerm forwards(vertex, edgeStart, edgeEnd, 6-vertex-edgeStart-edgeEnd);
NPerm reverse(vertex, edgeEnd, edgeStart, 6-vertex-edgeStart-edgeEnd);
if (discType < 4) {
for (int i = 0; i < 3; i++) {
if (triDiscArcs(discType, i) == forwards)
return true;
if (triDiscArcs(discType, i) == reverse)
return false;
}
}
else if (discType < 7) {
for (int i = 0; i < 4; i++) {
if (quadDiscArcs(discType - 4, i) == forwards)
return true;
if (quadDiscArcs(discType - 4, i) == reverse)
return false;
}
}
else {
for (int i = 0; i < 8; i++) {
if (octDiscArcs(discType - 7, i) == forwards)
return true;
if (octDiscArcs(discType - 7, i) == reverse)
return false;
}
}
return false;
}
NDiscSetTet::NDiscSetTet(const NNormalSurface& surface,
unsigned long tetIndex) {
int i;
for (i=0; i<4; i++)
internalNDiscs[i] = surface.getTriangleCoord(tetIndex, i).longValue();
for (i=4; i<7; i++)
internalNDiscs[i] = surface.getQuadCoord(tetIndex, i - 4).longValue();
for (i=7; i<10; i++)
internalNDiscs[i] = surface.getOctCoord(tetIndex, i - 7).longValue();
}
unsigned long NDiscSetTet::arcFromDisc(int /* arcFace */, int arcVertex,
int discType, unsigned long discNumber) const {
// Is it a triangle?
if (discType < 4)
return discNumber;
// It's a quad or an octagon.
// Note that there is at most one octagonal or quad type present
// (since the surface must be embedded), so this must be it.
if (arcVertex == 0 || arcVertex ==
vertexSplitPartner[(discType - 1) % 3][0])
return internalNDiscs[arcVertex] + discNumber;
else
return internalNDiscs[arcVertex] + internalNDiscs[discType]
- discNumber - 1;
}
void NDiscSetTet::discFromArc(int arcFace, int arcVertex,
unsigned long arcNumber,
int& discType, unsigned long& discNumber) const {
// Is it a triangle?
if (arcNumber < internalNDiscs[arcVertex]) {
discType = arcVertex;
discNumber = arcNumber;
return;
}
// It's a quad or an octagon.
// Note that there is at most one octagonal or quad type present
// (since the surface must be embedded), so this must be it.
if (internalNDiscs[vertexSplit[arcVertex][arcFace] + 4] > 0)
discType = vertexSplit[arcVertex][arcFace] + 4;
else if (internalNDiscs[vertexSplitMeeting[arcVertex][arcFace][0] + 7] > 0)
discType = vertexSplitMeeting[arcVertex][arcFace][0] + 7;
else
discType = vertexSplitMeeting[arcVertex][arcFace][1] + 7;
if (arcVertex == 0 || arcVertex ==
vertexSplitPartner[(discType - 1) % 3][0])
discNumber = arcNumber - internalNDiscs[arcVertex];
else
discNumber = internalNDiscs[discType] -
(arcNumber - internalNDiscs[arcVertex]) - 1;
}
NDiscSetSurface::NDiscSetSurface(const NNormalSurface& surface, bool) :
triangulation(surface.getTriangulation()) {
unsigned long tot = triangulation->getNumberOfTetrahedra();
if (tot == 0)
discSets = 0;
else
discSets = new NDiscSetTet*[tot];
}
NDiscSetSurface::NDiscSetSurface(const NNormalSurface& surface) :
triangulation(surface.getTriangulation()) {
unsigned long tot = triangulation->getNumberOfTetrahedra();
if (tot == 0)
discSets = 0;
else {
discSets = new NDiscSetTet*[tot];
for (unsigned long index = 0; index < tot; index++)
discSets[index] = new NDiscSetTet(surface, index);
}
}
NDiscSetSurface::~NDiscSetSurface() {
if (discSets) {
unsigned long tot = nTets();
for (unsigned long index = 0; index < tot; index++)
delete discSets[index];
delete[] discSets;
}
}
NDiscSpec* NDiscSetSurface::adjacentDisc(const NDiscSpec& disc,
NPerm arc, NPerm& adjArc) const {
NTetrahedron* tet = triangulation->getTetrahedron(disc.tetIndex);
int arcFace = arc[3];
if (tet->getAdjacentTetrahedron(arcFace) == 0)
return 0;
NDiscSpec* ans = new NDiscSpec;
ans->tetIndex = triangulation->tetrahedronIndex(
tet->getAdjacentTetrahedron(arcFace));
adjArc = tet->getAdjacentTetrahedronGluing(arcFace) * arc;
unsigned long arcNumber = discSets[disc.tetIndex]->arcFromDisc(
arcFace, arc[0], disc.type, disc.number);
discSets[ans->tetIndex]->discFromArc(adjArc[3], adjArc[0], arcNumber,
ans->type, ans->number);
return ans;
}
void NDiscSpecIterator::makeValid() {
while (current.number ==
internalDiscSet->nDiscs(current.tetIndex, current.type)) {
current.number = 0;
current.type++;
if (current.type == 10) {
current.type = 0;
current.tetIndex++;
if (current.tetIndex == internalDiscSet->nTets())
break;
}
}
}
} // namespace regina
|
