Developer Documentation
OFFWriter.cc
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41
42
43
44
45//== INCLUDES =================================================================
46
47#include <fstream>
48#include <OpenMesh/Core/System/config.h>
49#include <OpenMesh/Core/System/omstream.hh>
50#include <OpenMesh/Core/Utils/Endian.hh>
51#include <OpenMesh/Core/IO/IOManager.hh>
52#include <OpenMesh/Core/IO/BinaryHelper.hh>
53#include <OpenMesh/Core/IO/writer/OFFWriter.hh>
54
55//=== NAMESPACES ==============================================================
56
57
58namespace OpenMesh {
59namespace IO {
60
61
62//=== INSTANCIATE =============================================================
63
64
65// register the OFFLoader singleton with MeshLoader
66_OFFWriter_ __OFFWriterInstance;
67_OFFWriter_& OFFWriter() { return __OFFWriterInstance; }
68
69
70//=== IMPLEMENTATION ==========================================================
71
72
73_OFFWriter_::_OFFWriter_() { IOManager().register_module(this); }
74
75
76//-----------------------------------------------------------------------------
77
78
79bool
80_OFFWriter_::
81write(const std::string& _filename, BaseExporter& _be, const Options& _writeOptions, std::streamsize _precision) const
82{
83 std::ofstream out(_filename.c_str(), (_writeOptions.check(Options::Binary) ? std::ios_base::binary | std::ios_base::out
84 : std::ios_base::out) );
85
86 return write(out, _be, _writeOptions, _precision);
87}
88
89//-----------------------------------------------------------------------------
90
91
92bool
93_OFFWriter_::
94write(std::ostream& _os, BaseExporter& _be, const Options& _writeOptions, std::streamsize _precision) const
95{
96 // check exporter features
97 if ( !check( _be, _writeOptions ) )
98 return false;
99
100
101 // check writer features
102 if ( _writeOptions.check(Options::FaceNormal) ) // not supported by format
103 return false;
104
105
106 if (!_os.good())
107 {
108 omerr() << "[OFFWriter] : cannot write to stream "
109 << std::endl;
110 return false;
111 }
112
113 // write header line
114 if (_writeOptions.check(Options::VertexTexCoord)) _os << "ST";
115 if (_writeOptions.check(Options::VertexColor) || _writeOptions.check(Options::FaceColor)) _os << "C";
116 if (_writeOptions.check(Options::VertexNormal)) _os << "N";
117 _os << "OFF";
118 if (_writeOptions.check(Options::Binary)) _os << " BINARY";
119 _os << "\n";
120
121 if (!_writeOptions.check(Options::Binary))
122 _os.precision(_precision);
123
124 // write to file
125 bool result = (_writeOptions.check(Options::Binary) ?
126 write_binary(_os, _be, _writeOptions) :
127 write_ascii(_os, _be, _writeOptions));
128
129
130 // return result
131 return result;
132}
133
134//-----------------------------------------------------------------------------
135
136
137bool
138_OFFWriter_::
139write_ascii(std::ostream& _out, BaseExporter& _be, const Options& _writeOptions) const
140{
141
142 unsigned int i, nV, nF;
143 Vec3f v, n;
144 Vec2f t;
145 OpenMesh::Vec3i c;
146 OpenMesh::Vec4i cA;
147 OpenMesh::Vec3f cf;
148 OpenMesh::Vec4f cAf;
149 VertexHandle vh;
150 std::vector<VertexHandle> vhandles;
151
152
153 // #vertices, #faces
154 _out << _be.n_vertices() << " ";
155 _out << _be.n_faces() << " ";
156 _out << 0 << "\n";
157
158 if (_writeOptions.color_is_float())
159 _out << std::fixed;
160
161
162 // vertex data (point, normals, colors, texcoords)
163 for (i=0, nV=int(_be.n_vertices()); i<nV; ++i)
164 {
165 vh = VertexHandle(i);
166 v = _be.point(vh);
167
168 //Vertex
169 _out << v[0] << " " << v[1] << " " << v[2];
170
171 // VertexNormal
172 if ( _writeOptions.vertex_has_normal() ) {
173 n = _be.normal(vh);
174 _out << " " << n[0] << " " << n[1] << " " << n[2];
175 }
176
177 // VertexColor
178 if ( _writeOptions.vertex_has_color() ) {
179 if ( _writeOptions.color_is_float() ) {
180 //with alpha
181 if ( _writeOptions.color_has_alpha() ){
182 cAf = _be.colorAf(vh);
183 _out << " " << cAf;
184 }else{
185 //without alpha
186 cf = _be.colorf(vh);
187 _out << " " << cf;
188 }
189 } else {
190 //with alpha
191 if ( _writeOptions.color_has_alpha() ){
192 cA = _be.colorA(vh);
193 _out << " " << cA;
194 }else{
195 //without alpha
196 c = _be.color(vh);
197 _out << " " << c;
198 }
199 }
200 }
201
202 // TexCoord
203 if (_writeOptions.vertex_has_texcoord() ) {
204 t = _be.texcoord(vh);
205 _out << " " << t[0] << " " << t[1];
206 }
207
208 _out << '\n';
209
210 }
211
212 // faces (indices starting at 0)
213 if (_be.is_triangle_mesh())
214 {
215 for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
216 {
217 _be.get_vhandles(FaceHandle(i), vhandles);
218 _out << 3 << " ";
219 _out << vhandles[0].idx() << " ";
220 _out << vhandles[1].idx() << " ";
221 _out << vhandles[2].idx();
222
223 //face color
224 if ( _writeOptions.face_has_color() ){
225 if ( _writeOptions.color_is_float() ) {
226 //with alpha
227 if ( _writeOptions.color_has_alpha() ){
228 cAf = _be.colorAf( FaceHandle(i) );
229 _out << " " << cAf;
230 }else{
231 //without alpha
232 cf = _be.colorf( FaceHandle(i) );
233 _out << " " << cf;
234 }
235 } else {
236 //with alpha
237 if ( _writeOptions.color_has_alpha() ){
238 cA = _be.colorA( FaceHandle(i) );
239 _out << " " << cA;
240 }else{
241 //without alpha
242 c = _be.color( FaceHandle(i) );
243 _out << " " << c;
244 }
245 }
246 }
247 _out << '\n';
248 }
249 }
250 else
251 {
252 for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
253 {
254 nV = _be.get_vhandles(FaceHandle(i), vhandles);
255 _out << nV << " ";
256 for (size_t j=0; j<vhandles.size(); ++j)
257 _out << vhandles[j].idx() << " ";
258
259 //face color
260 if ( _writeOptions.face_has_color() ){
261 if ( _writeOptions.color_is_float() ) {
262 //with alpha
263 if ( _writeOptions.color_has_alpha() ){
264 cAf = _be.colorAf( FaceHandle(i) );
265 _out << " " << cAf;
266 }else{
267 //without alpha
268 cf = _be.colorf( FaceHandle(i) );
269 _out << " " << cf;
270 }
271 } else {
272 //with alpha
273 if ( _writeOptions.color_has_alpha() ){
274 cA = _be.colorA( FaceHandle(i) );
275 _out << " " << cA;
276 }else{
277 //without alpha
278 c = _be.color( FaceHandle(i) );
279 _out << " " << c;
280 }
281 }
282 }
283
284 _out << '\n';
285 }
286 }
287
288
289 return true;
290}
291
292
293//-----------------------------------------------------------------------------
294
295void _OFFWriter_::writeValue(std::ostream& _out, int value) const {
296
297 uint32_t tmp = value;
298 store(_out, tmp, false);
299}
300
301void _OFFWriter_::writeValue(std::ostream& _out, unsigned int value) const {
302
303 uint32_t tmp = value;
304 store(_out, tmp, false);
305}
306
307void _OFFWriter_::writeValue(std::ostream& _out, float value) const {
308
309 float32_t tmp = value;
310 store(_out, tmp, false);
311}
312
313bool
314_OFFWriter_::
315write_binary(std::ostream& _out, BaseExporter& _be, const Options& _writeOptions) const
316{
317
318 unsigned int i, nV, nF;
319 Vec3f v, n;
320 Vec2f t;
321 OpenMesh::Vec4i c;
322 OpenMesh::Vec4f cf;
323 VertexHandle vh;
324 std::vector<VertexHandle> vhandles;
325
326 // #vertices, #faces
327 writeValue(_out, (uint)_be.n_vertices() );
328 writeValue(_out, (uint) _be.n_faces() );
329 writeValue(_out, 0 );
330
331 // vertex data (point, normals, texcoords)
332 for (i=0, nV=int(_be.n_vertices()); i<nV; ++i)
333 {
334 vh = VertexHandle(i);
335 v = _be.point(vh);
336
337 //vertex
338 writeValue(_out, v[0]);
339 writeValue(_out, v[1]);
340 writeValue(_out, v[2]);
341
342 // vertex normal
343 if ( _writeOptions.vertex_has_normal() ) {
344 n = _be.normal(vh);
345 writeValue(_out, n[0]);
346 writeValue(_out, n[1]);
347 writeValue(_out, n[2]);
348 }
349 // vertex color
350 if ( _writeOptions.vertex_has_color() ) {
351 if ( _writeOptions.color_is_float() ) {
352 cf = _be.colorAf(vh);
353 writeValue(_out, cf[0]);
354 writeValue(_out, cf[1]);
355 writeValue(_out, cf[2]);
356
357 if ( _writeOptions.color_has_alpha() )
358 writeValue(_out, cf[3]);
359 } else {
360 c = _be.colorA(vh);
361 writeValue(_out, c[0]);
362 writeValue(_out, c[1]);
363 writeValue(_out, c[2]);
364
365 if ( _writeOptions.color_has_alpha() )
366 writeValue(_out, c[3]);
367 }
368 }
369 // texCoords
370 if (_writeOptions.vertex_has_texcoord() ) {
371 t = _be.texcoord(vh);
372 writeValue(_out, t[0]);
373 writeValue(_out, t[1]);
374 }
375
376 }
377
378 // faces (indices starting at 0)
379 if (_be.is_triangle_mesh())
380 {
381 for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
382 {
383 //face
384 _be.get_vhandles(FaceHandle(i), vhandles);
385 writeValue(_out, 3);
386 writeValue(_out, vhandles[0].idx());
387 writeValue(_out, vhandles[1].idx());
388 writeValue(_out, vhandles[2].idx());
389
390 //face color
391 if ( _writeOptions.face_has_color() ){
392 if ( _writeOptions.color_is_float() ) {
393 cf = _be.colorAf( FaceHandle(i) );
394 writeValue(_out, cf[0]);
395 writeValue(_out, cf[1]);
396 writeValue(_out, cf[2]);
397
398 if ( _writeOptions.color_has_alpha() )
399 writeValue(_out, cf[3]);
400 } else {
401 c = _be.colorA( FaceHandle(i) );
402 writeValue(_out, c[0]);
403 writeValue(_out, c[1]);
404 writeValue(_out, c[2]);
405
406 if ( _writeOptions.color_has_alpha() )
407 writeValue(_out, c[3]);
408 }
409 }
410 }
411 }
412 else
413 {
414 for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
415 {
416 //face
417 nV = _be.get_vhandles(FaceHandle(i), vhandles);
418 writeValue(_out, nV);
419 for (size_t j=0; j<vhandles.size(); ++j)
420 writeValue(_out, vhandles[j].idx() );
421
422 //face color
423 if ( _writeOptions.face_has_color() ){
424 if ( _writeOptions.color_is_float() ) {
425 cf = _be.colorAf( FaceHandle(i) );
426 writeValue(_out, cf[0]);
427 writeValue(_out, cf[1]);
428 writeValue(_out, cf[2]);
429
430 if ( _writeOptions.color_has_alpha() )
431 writeValue(_out, cf[3]);
432 } else {
433 c = _be.colorA( FaceHandle(i) );
434 writeValue(_out, c[0]);
435 writeValue(_out, c[1]);
436 writeValue(_out, c[2]);
437
438 if ( _writeOptions.color_has_alpha() )
439 writeValue(_out, c[3]);
440 }
441 }
442 }
443 }
444
445 return true;
446}
447
448// ----------------------------------------------------------------------------
449
450
451size_t
452_OFFWriter_::
453binary_size(BaseExporter& _be, const Options& _writeOptions) const
454{
455 size_t header(0);
456 size_t data(0);
457
458 size_t _3floats(3*sizeof(float));
459 size_t _3ui(3*sizeof(unsigned int));
460 size_t _4ui(4*sizeof(unsigned int));
461
462 if ( !_writeOptions.is_binary() )
463 return 0;
464 else
465 {
466 size_t _3longs(3*sizeof(long));
467
468 header += 11; // 'OFF BINARY\n'
469 header += _3longs; // #V #F #E
470 data += _be.n_vertices() * _3floats; // vertex data
471 }
472
473 if ( _writeOptions.vertex_has_normal() && _be.has_vertex_normals() )
474 {
475 header += 1; // N
476 data += _be.n_vertices() * _3floats;
477 }
478
479 if ( _writeOptions.vertex_has_color() && _be.has_vertex_colors() )
480 {
481 header += 1; // C
482 data += _be.n_vertices() * _3floats;
483 }
484
485 if ( _writeOptions.vertex_has_texcoord() && _be.has_vertex_texcoords() )
486 {
487 size_t _2floats(2*sizeof(float));
488 header += 2; // ST
489 data += _be.n_vertices() * _2floats;
490 }
491
492 // topology
493 if (_be.is_triangle_mesh())
494 {
495 data += _be.n_faces() * _4ui;
496 }
497 else
498 {
499 unsigned int i, nF;
500 std::vector<VertexHandle> vhandles;
501
502 for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
503 data += _be.get_vhandles(FaceHandle(i), vhandles) * sizeof(unsigned int);
504
505 }
506
507 // face colors
508 if ( _writeOptions.face_has_color() && _be.has_face_colors() ){
509 if ( _writeOptions.color_has_alpha() )
510 data += _be.n_faces() * _4ui;
511 else
512 data += _be.n_faces() * _3ui;
513 }
514
515 return header+data;
516}
517
518
519//=============================================================================
520} // namespace IO
521} // namespace OpenMesh
522//=============================================================================
OpenMesh::IO::Options
Set options for reader/writer modules.
Definition: Options.hh:92
OpenMesh::IO::Options::FaceNormal
@ FaceNormal
Has (r) / store (w) face normals.
Definition: Options.hh:109
OpenMesh::IO::Options::FaceColor
@ FaceColor
Has (r) / store (w) face colors.
Definition: Options.hh:110
OpenMesh::IO::Options::Binary
@ Binary
Set binary mode for r/w.
Definition: Options.hh:101
OpenMesh::IO::Options::VertexNormal
@ VertexNormal
Has (r) / store (w) vertex normals.
Definition: Options.hh:105
OpenMesh::IO::Options::VertexTexCoord
@ VertexTexCoord
Has (r) / store (w) texture coordinates.
Definition: Options.hh:107
OpenMesh::IO::Options::VertexColor
@ VertexColor
Has (r) / store (w) vertex colors.
Definition: Options.hh:106
OpenMesh::IO::_IOManager_::register_module
bool register_module(BaseReader *_bl)
Definition: IOManager.hh:217
OpenMesh::IO::_OFFWriter_
Definition: OFFWriter.hh:93
OpenMesh::IO::_OFFWriter_::write
bool write(const std::string &, BaseExporter &, const Options &, std::streamsize _precision=6) const override
Definition: OFFWriter.cc:81
OpenMesh::IO::_OFFWriter_::binary_size
size_t binary_size(BaseExporter &_be, const Options &_opt) const override
Returns expected size of file if binary format is supported else 0.
Definition: OFFWriter.cc:453
OpenMesh::IO::uint32_t
unsigned int uint32_t
Definition: SR_types.hh:85
OpenMesh::IO::IOManager
_IOManager_ & IOManager()
Definition: IOManager.cc:72
OpenMesh::IO::float32_t
float float32_t
Definition: SR_types.hh:92
OpenMesh::IO::__OFFWriterInstance
_OFFWriter_ __OFFWriterInstance
Declare the single entity of the OFF writer.
Definition: OFFWriter.cc:66
OpenMesh::FaceHandle
Handle for a face entity.
Definition: Handles.hh:142
OpenMesh::VertexHandle
Handle for a vertex entity.
Definition: Handles.hh:121