-
Notifications
You must be signed in to change notification settings - Fork 556
/
hbr_tutorial_2.cpp
264 lines (205 loc) · 8.24 KB
/
hbr_tutorial_2.cpp
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
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
//
// Copyright 2013 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the trade
// names, trademarks, service marks, or product names of the Licensor
// and its affiliates, except as required to comply with Section 4(c) of
// the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
//------------------------------------------------------------------------------
// Tutorial description:
//
// This tutorial shows how to subdivide uniformly a simple Hbr mesh. We are
// building upon previous tutorials and assuming a fully instantiated mesh:
// we start with an HbrMesh pointer initialized from the same pyramid shape
// used in hbr_tutorial_0.
//
// We then apply the Refine() function sequentially to all the faces in the
// mesh to generate several levels of uniform subdivision. The resulting data
// is then dumped to the terminal in Wavefront OBJ format for inspection.
//
#include <opensubdiv/hbr/mesh.h>
#include <opensubdiv/hbr/catmark.h>
#include <cassert>
#include <cstdio>
//------------------------------------------------------------------------------
//
// For this tutorial, we have to flesh out the Vertex class further. Note that now
// the copy constructor, Clear() and AddwithWeight() methods have been
// implemented to interpolate our float3 position data.
//
// This vertex specialization pattern leaves client-code free to implement
// arbitrary vertex primvar data schemes (or none at all to conserve efficiency)
//
struct Vertex {
// Hbr minimal required interface ----------------------
Vertex() { }
Vertex(int /*i*/) { }
Vertex(Vertex const & src) {
_position[0] = src._position[0];
_position[1] = src._position[1];
_position[2] = src._position[2];
}
void Clear( void * =0 ) {
_position[0]=_position[1]=_position[2]=0.0f;
}
void AddWithWeight(Vertex const & src, float weight) {
_position[0]+=weight*src._position[0];
_position[1]+=weight*src._position[1];
_position[2]+=weight*src._position[2];
}
void AddVaryingWithWeight(Vertex const &, float) { }
// Public interface ------------------------------------
void SetPosition(float x, float y, float z) {
_position[0]=x;
_position[1]=y;
_position[2]=z;
}
const float * GetPosition() const {
return _position;
}
private:
float _position[3];
};
typedef OpenSubdiv::HbrMesh<Vertex> Hmesh;
typedef OpenSubdiv::HbrFace<Vertex> Hface;
typedef OpenSubdiv::HbrVertex<Vertex> Hvertex;
typedef OpenSubdiv::HbrHalfedge<Vertex> Hhalfedge;
Hmesh * createMesh();
//------------------------------------------------------------------------------
int main(int, char **) {
Hmesh * hmesh = createMesh();
int maxlevel=2, // 2 levels of subdivision
firstface=0, // marker to the first face index of level 2
firstvertex=0; // marker to the first vertex index of level 2
// Refine the mesh to 'maxlevel'
for (int level=0; level<maxlevel; ++level) {
// Total number of faces in the mesh, across all levels
//
// Note: this function iterates over the list of faces and can be slow
int nfaces = hmesh->GetNumFaces();
if (level==(maxlevel-1)) {
// Save our vertex marker
firstvertex = hmesh->GetNumVertices();
}
// Iterate over the faces of the current level of subdivision
for (int face=firstface; face<nfaces; ++face) {
Hface * f = hmesh->GetFace(face);
// Note: hole tags would have to be dealt with here.
f->Refine();
}
// Save our face index marker for the next level
firstface = nfaces;
}
{ // Output OBJ of the highest level refined -----------
// Print vertex positions
int nverts = hmesh->GetNumVertices();
for (int vert=firstvertex; vert<nverts; ++vert) {
float const * pos = hmesh->GetVertex(vert)->GetData().GetPosition();
printf("v %f %f %f\n", pos[0], pos[1], pos[2]);
}
// Print faces
for (int face=firstface; face<hmesh->GetNumFaces(); ++face) {
Hface * f = hmesh->GetFace(face);
assert(f->GetNumVertices()==4 );
printf("f ");
for (int vert=0; vert<4; ++vert) {
// OBJ uses 1-based arrays
printf("%d ", f->GetVertex(vert)->GetID() - firstvertex + 1);
}
printf("\n");
}
}
}
//------------------------------------------------------------------------------
// Creates an Hbr mesh
//
// see hbr_tutorial_0 and hbr_tutorial_1 for more details
//
Hmesh *
createMesh() {
// Pyramid geometry from catmark_pyramid.h
static float verts[5][3] = {{ 0.0f, 0.0f, 2.0f},
{ 0.0f, -2.0f, 0.0f},
{ 2.0f, 0.0f, 0.0f},
{ 0.0f, 2.0f, 0.0f},
{-2.0f, 0.0f, 0.0f}};
static int nverts = 5,
nfaces = 5;
static int facenverts[5] = { 3, 3, 3, 3, 4 };
static int faceverts[16] = { 0, 1, 2,
0, 2, 3,
0, 3, 4,
0, 4, 1,
4, 3, 2, 1 };
OpenSubdiv::HbrCatmarkSubdivision<Vertex> * catmark =
new OpenSubdiv::HbrCatmarkSubdivision<Vertex>();
Hmesh * hmesh = new Hmesh(catmark);
// Populate the vertices
Vertex v;
for (int i=0; i<nverts; ++i) {
v.SetPosition(verts[i][0], verts[i][1], verts[i][2]);
hmesh->NewVertex(i, v);
}
// Create the topology
int * fv = faceverts;
for (int i=0; i<nfaces; ++i) {
int nv = facenverts[i];
bool valid = true;
for(int j=0;j<nv;j++) {
Hvertex const * origin = hmesh->GetVertex(fv[j]),
* destination = hmesh->GetVertex(fv[(j+1)%nv]);
Hhalfedge const * opposite = destination->GetEdge(origin);
// Make sure that the vertices exist in the mesh
if (origin==NULL || destination==NULL) {
printf(" An edge was specified that connected a nonexistent vertex\n");
valid=false;
break;
}
// Check for a degenerate edge
if (origin == destination) {
printf(" An edge was specified that connected a vertex to itself\n");
valid=false;
break;
}
// Check that no more than 2 faces are adjacent to the edge
if (opposite && opposite->GetOpposite() ) {
printf(" A non-manifold edge incident to more than 2 faces was found\n");
valid=false;
break;
}
// Check that the edge is unique and oriented properly
if (origin->GetEdge(destination)) {
printf(" An edge connecting two vertices was specified more than once."
" It's likely that an incident face was flipped\n");
valid=false;
break;
}
}
if (valid) {
hmesh->NewFace(nv, fv, 0);
} else {
printf(" Skipped face %d\n", i);
}
fv+=nv;
}
hmesh->SetInterpolateBoundaryMethod(Hmesh::k_InterpolateBoundaryEdgeOnly);
hmesh->Finish();
return hmesh;
}
//------------------------------------------------------------------------------