QGIS API Documentation  3.16.0-Hannover (43b64b13f3)
qgscoordinatetransformcontext.cpp
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1 /***************************************************************************
2  qgscoordinatetransformcontext.cpp
3  ---------------------------------
4  begin : November 2017
5  copyright : (C) 2017 by Nyall Dawson
6  email : nyall dot dawson at gmail dot com
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
18 #include "qgscoordinatetransformcontext.h"
19 #include "qgscoordinatetransformcontext_p.h"
20 #include "qgscoordinatetransform.h"
21 #include "qgssettings.h"
22 #include "qgsprojutils.h"
23 
24 QString crsToKey( const QgsCoordinateReferenceSystem &crs )
25 {
26  return crs.authid().isEmpty() ? crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED ) : crs.authid();
27 }
28 
29 template<>
30 bool qMapLessThanKey<QPair<QgsCoordinateReferenceSystem, QgsCoordinateReferenceSystem>>( const QPair<QgsCoordinateReferenceSystem, QgsCoordinateReferenceSystem> &key1,
31  const QPair<QgsCoordinateReferenceSystem, QgsCoordinateReferenceSystem> &key2 )
32 {
33  const QPair< QString, QString > key1String = qMakePair( crsToKey( key1.first ), crsToKey( key1.second ) );
34  const QPair< QString, QString > key2String = qMakePair( crsToKey( key2.first ), crsToKey( key2.second ) );
35  return key1String < key2String;
36 }
37 
38 QgsCoordinateTransformContext::QgsCoordinateTransformContext()
39  : d( new QgsCoordinateTransformContextPrivate() )
40 {}
41 
42 QgsCoordinateTransformContext::~QgsCoordinateTransformContext() = default;
43 
44 QgsCoordinateTransformContext::QgsCoordinateTransformContext( const QgsCoordinateTransformContext &rhs ) //NOLINT
45  : d( rhs.d )
46 {}
47 
48 QgsCoordinateTransformContext &QgsCoordinateTransformContext::operator=( const QgsCoordinateTransformContext &rhs ) //NOLINT
49 {
50  d = rhs.d;
51  return *this;
52 }
53 
54 bool QgsCoordinateTransformContext::operator==( const QgsCoordinateTransformContext &rhs ) const
55 {
56  if ( d == rhs.d )
57  return true;
58 
59  d->mLock.lockForRead();
60  rhs.d->mLock.lockForRead();
61  bool equal = d->mSourceDestDatumTransforms == rhs.d->mSourceDestDatumTransforms;
62  d->mLock.unlock();
63  rhs.d->mLock.unlock();
64  return equal;
65 }
66 
67 void QgsCoordinateTransformContext::clear()
68 {
69  d.detach();
70  // play it safe
71  d->mLock.lockForWrite();
72  d->mSourceDestDatumTransforms.clear();
73  d->mLock.unlock();
74 }
75 
76 QMap<QPair<QString, QString>, QgsDatumTransform::TransformPair> QgsCoordinateTransformContext::sourceDestinationDatumTransforms() const
77 {
78 #if PROJ_VERSION_MAJOR>=6
79  return QMap<QPair<QString, QString>, QgsDatumTransform::TransformPair>();
80 #else
81  d->mLock.lockForRead();
82  auto res = d->mSourceDestDatumTransforms;
83  res.detach();
84  d->mLock.unlock();
85  return res;
86 #endif
87 }
88 
89 QMap<QPair<QString, QString>, QString> QgsCoordinateTransformContext::coordinateOperations() const
90 {
91 #if PROJ_VERSION_MAJOR>=6
92  d->mLock.lockForRead();
93  auto res = d->mSourceDestDatumTransforms;
94  res.detach();
95  d->mLock.unlock();
96  QMap<QPair<QString, QString>, QString> results;
97  for ( auto it = res.constBegin(); it != res.constEnd(); ++it )
98  results.insert( qMakePair( it.key().first.authid(), it.key().second.authid() ), it.value().operation );
99 
100  return results;
101 #else
102  return QMap<QPair<QString, QString>, QString>();
103 #endif
104 }
105 
106 bool QgsCoordinateTransformContext::addSourceDestinationDatumTransform( const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs, int sourceTransform, int destinationTransform )
107 {
108  if ( !sourceCrs.isValid() || !destinationCrs.isValid() )
109  return false;
110 #if PROJ_VERSION_MAJOR>=6
111  Q_UNUSED( sourceTransform )
112  Q_UNUSED( destinationTransform )
113  return false;
114 #else
115  d.detach();
116  d->mLock.lockForWrite();
117  d->mSourceDestDatumTransforms.insert( qMakePair( sourceCrs.authid(), destinationCrs.authid() ), QgsDatumTransform::TransformPair( sourceTransform, destinationTransform ) );
118  d->mLock.unlock();
119  return true;
120 #endif
121 }
122 
123 bool QgsCoordinateTransformContext::addCoordinateOperation( const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs, const QString &coordinateOperationProjString, bool allowFallback )
124 {
125  if ( !sourceCrs.isValid() || !destinationCrs.isValid() )
126  return false;
127 #if PROJ_VERSION_MAJOR>=6
128  d.detach();
129  d->mLock.lockForWrite();
130  QgsCoordinateTransformContextPrivate::OperationDetails details;
131  details.operation = coordinateOperationProjString;
132  details.allowFallback = allowFallback;
133  d->mSourceDestDatumTransforms.insert( qMakePair( sourceCrs, destinationCrs ), details );
134  d->mLock.unlock();
135  return true;
136 #else
137  Q_UNUSED( coordinateOperationProjString )
138  Q_UNUSED( allowFallback )
139  return false;
140 #endif
141 }
142 
143 void QgsCoordinateTransformContext::removeSourceDestinationDatumTransform( const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs )
144 {
145  removeCoordinateOperation( sourceCrs, destinationCrs );
146 }
147 
148 void QgsCoordinateTransformContext::removeCoordinateOperation( const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs )
149 {
150 #if PROJ_VERSION_MAJOR>=6
151  d->mSourceDestDatumTransforms.remove( qMakePair( sourceCrs, destinationCrs ) );
152 #else
153  d->mSourceDestDatumTransforms.remove( qMakePair( sourceCrs.authid(), destinationCrs.authid() ) );
154 #endif
155 }
156 
157 bool QgsCoordinateTransformContext::hasTransform( const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination ) const
158 {
159 #if PROJ_VERSION_MAJOR>=6
160  const QString t = calculateCoordinateOperation( source, destination );
161  return !t.isEmpty();
162 #else
163  Q_NOWARN_DEPRECATED_PUSH
164  QgsDatumTransform::TransformPair t = calculateDatumTransforms( source, destination );
165  Q_NOWARN_DEPRECATED_POP
166  // calculateDatumTransforms already takes care of switching source and destination
167  return t.sourceTransformId != -1 || t.destinationTransformId != -1;
168 #endif
169 }
170 
171 QgsDatumTransform::TransformPair QgsCoordinateTransformContext::calculateDatumTransforms( const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination ) const
172 {
173 #if PROJ_VERSION_MAJOR>=6
174  Q_UNUSED( source )
175  Q_UNUSED( destination )
176  return QgsDatumTransform::TransformPair( -1, -1 );
177 #else
178  QString srcKey = source.authid();
179  QString destKey = destination.authid();
180 
181  d->mLock.lockForRead();
182  // highest priority is exact match for source/dest pair
183  QgsDatumTransform::TransformPair res = d->mSourceDestDatumTransforms.value( qMakePair( srcKey, destKey ), QgsDatumTransform::TransformPair( -1, -1 ) );
184  if ( res.sourceTransformId == -1 && res.destinationTransformId == -1 )
185  {
186  // try to reverse
187  QgsDatumTransform::TransformPair res2 = d->mSourceDestDatumTransforms.value( qMakePair( destKey, srcKey ), QgsDatumTransform::TransformPair( -1, -1 ) );
188  res = QgsDatumTransform::TransformPair( res2.destinationTransformId, res2.sourceTransformId );
189  }
190  d->mLock.unlock();
191  return res;
192 #endif
193 }
194 
195 QString QgsCoordinateTransformContext::calculateCoordinateOperation( const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination ) const
196 {
197 #if PROJ_VERSION_MAJOR>=6
198  if ( !source.isValid() || !destination.isValid() )
199  return QString();
200 
201  d->mLock.lockForRead();
202  QgsCoordinateTransformContextPrivate::OperationDetails res = d->mSourceDestDatumTransforms.value( qMakePair( source, destination ), QgsCoordinateTransformContextPrivate::OperationDetails() );
203  if ( res.operation.isEmpty() )
204  {
205  // try to reverse
206  res = d->mSourceDestDatumTransforms.value( qMakePair( destination, source ), QgsCoordinateTransformContextPrivate::OperationDetails() );
207  }
208  d->mLock.unlock();
209  return res.operation;
210 #else
211  Q_UNUSED( source )
212  Q_UNUSED( destination )
213  return QString();
214 #endif
215 }
216 
217 bool QgsCoordinateTransformContext::allowFallbackTransform( const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination ) const
218 {
219 #if PROJ_VERSION_MAJOR>=6
220  if ( !source.isValid() || !destination.isValid() )
221  return false;
222 
223  d->mLock.lockForRead();
224  QgsCoordinateTransformContextPrivate::OperationDetails res = d->mSourceDestDatumTransforms.value( qMakePair( source, destination ), QgsCoordinateTransformContextPrivate::OperationDetails() );
225  if ( res.operation.isEmpty() )
226  {
227  // try to reverse
228  res = d->mSourceDestDatumTransforms.value( qMakePair( destination, source ), QgsCoordinateTransformContextPrivate::OperationDetails() );
229  }
230  d->mLock.unlock();
231  return res.allowFallback;
232 #else
233  Q_UNUSED( source )
234  Q_UNUSED( destination )
235  return false;
236 #endif
237 }
238 
239 bool QgsCoordinateTransformContext::mustReverseCoordinateOperation( const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination ) const
240 {
241 #if PROJ_VERSION_MAJOR>=6
242  if ( !source.isValid() || !destination.isValid() )
243  return false;
244 
245  d->mLock.lockForRead();
246  QgsCoordinateTransformContextPrivate::OperationDetails res = d->mSourceDestDatumTransforms.value( qMakePair( source, destination ), QgsCoordinateTransformContextPrivate::OperationDetails() );
247  if ( !res.operation.isEmpty() )
248  {
249  d->mLock.unlock();
250  return false;
251  }
252  // see if the reverse operation is present
253  res = d->mSourceDestDatumTransforms.value( qMakePair( destination, source ), QgsCoordinateTransformContextPrivate::OperationDetails() );
254  if ( !res.operation.isEmpty() )
255  {
256  d->mLock.unlock();
257  return true;
258  }
259 
260  d->mLock.unlock();
261  return false;
262 #else
263  Q_UNUSED( source )
264  Q_UNUSED( destination )
265  return false;
266 #endif
267 }
268 
269 bool QgsCoordinateTransformContext::readXml( const QDomElement &element, const QgsReadWriteContext &, QStringList &missingTransforms )
270 {
271  d.detach();
272  d->mLock.lockForWrite();
273 
274  d->mSourceDestDatumTransforms.clear();
275 
276  const QDomNodeList contextNodes = element.elementsByTagName( QStringLiteral( "transformContext" ) );
277  if ( contextNodes.count() < 1 )
278  {
279  d->mLock.unlock();
280  return true;
281  }
282 
283  missingTransforms.clear();
284  bool result = true;
285 
286  const QDomElement contextElem = contextNodes.at( 0 ).toElement();
287 
288  // src/dest transforms
289  const QDomNodeList srcDestNodes = contextElem.elementsByTagName( QStringLiteral( "srcDest" ) );
290  for ( int i = 0; i < srcDestNodes.size(); ++i )
291  {
292  const QDomElement transformElem = srcDestNodes.at( i ).toElement();
293 
294 #if PROJ_VERSION_MAJOR>=6
295  const QDomElement srcElem = transformElem.firstChildElement( QStringLiteral( "src" ) );
296  const QDomElement destElem = transformElem.firstChildElement( QStringLiteral( "dest" ) );
297 
298  QgsCoordinateReferenceSystem srcCrs;
299  QgsCoordinateReferenceSystem destCrs;
300  if ( !srcElem.isNull() && !destElem.isNull() )
301  {
302  srcCrs.readXml( srcElem );
303  destCrs.readXml( destElem );
304  }
305  else
306  {
307  // for older project compatibility
308  const QString key1 = transformElem.attribute( QStringLiteral( "source" ) );
309  const QString key2 = transformElem.attribute( QStringLiteral( "dest" ) );
310  srcCrs = QgsCoordinateReferenceSystem( key1 );
311  destCrs = QgsCoordinateReferenceSystem( key2 );
312  }
313 
314  if ( !srcCrs.isValid() || !destCrs.isValid() )
315  continue;
316 
317  const QString coordinateOp = transformElem.attribute( QStringLiteral( "coordinateOp" ) );
318  const bool allowFallback = transformElem.attribute( QStringLiteral( "allowFallback" ), QStringLiteral( "1" ) ).toInt();
319 
320  // try to instantiate operation, and check for missing grids
321  if ( !QgsProjUtils::coordinateOperationIsAvailable( coordinateOp ) )
322  {
323  // not possible in current Proj 6 api!
324  // QgsCoordinateTransform will alert users to this, we don't need to use missingTransforms here
325  result = false;
326  }
327 
328  QgsCoordinateTransformContextPrivate::OperationDetails deets;
329  deets.operation = coordinateOp;
330  deets.allowFallback = allowFallback;
331  d->mSourceDestDatumTransforms.insert( qMakePair( srcCrs, destCrs ), deets );
332 #else
333  const QString key1 = transformElem.attribute( QStringLiteral( "source" ) );
334  const QString key2 = transformElem.attribute( QStringLiteral( "dest" ) );
335 
336  QString value1 = transformElem.attribute( QStringLiteral( "sourceTransform" ) );
337  QString value2 = transformElem.attribute( QStringLiteral( "destTransform" ) );
338 
339  Q_NOWARN_DEPRECATED_PUSH
340  int datumId1 = -1;
341  int datumId2 = -1;
342  //warn if value1 or value2 is non-empty, yet no matching transform was found
343  if ( !value1.isEmpty() )
344  {
345  datumId1 = QgsDatumTransform::projStringToDatumTransformId( value1 );
346  if ( datumId1 < 0 )
347  {
348  result = false;
349  missingTransforms << value1;
350  }
351  }
352  if ( !value2.isEmpty() )
353  {
354  datumId2 = QgsDatumTransform::projStringToDatumTransformId( value2 );
355  if ( datumId2 < 0 )
356  {
357  result = false;
358  missingTransforms << value2;
359  }
360  }
361  Q_NOWARN_DEPRECATED_POP
362 
363  d->mSourceDestDatumTransforms.insert( qMakePair( key1, key2 ), QgsDatumTransform::TransformPair( datumId1, datumId2 ) );
364 #endif
365  }
366 
367  d->mLock.unlock();
368  return result;
369 }
370 
371 void QgsCoordinateTransformContext::writeXml( QDomElement &element, const QgsReadWriteContext & ) const
372 {
373  d->mLock.lockForRead();
374 
375  QDomDocument doc = element.ownerDocument();
376 
377  QDomElement contextElem = doc.createElement( QStringLiteral( "transformContext" ) );
378 
379  //src/dest transforms
380  for ( auto it = d->mSourceDestDatumTransforms.constBegin(); it != d->mSourceDestDatumTransforms.constEnd(); ++ it )
381  {
382  QDomElement transformElem = doc.createElement( QStringLiteral( "srcDest" ) );
383 #if PROJ_VERSION_MAJOR>=6
384  QDomElement srcElem = doc.createElement( QStringLiteral( "src" ) );
385  QDomElement destElem = doc.createElement( QStringLiteral( "dest" ) );
386 
387  it.key().first.writeXml( srcElem, doc );
388  it.key().second.writeXml( destElem, doc );
389 
390  transformElem.appendChild( srcElem );
391  transformElem.appendChild( destElem );
392 
393  transformElem.setAttribute( QStringLiteral( "coordinateOp" ), it.value().operation );
394  transformElem.setAttribute( QStringLiteral( "allowFallback" ), it.value().allowFallback ? QStringLiteral( "1" ) : QStringLiteral( "0" ) );
395 #else
396  transformElem.setAttribute( QStringLiteral( "source" ), it.key().first );
397  transformElem.setAttribute( QStringLiteral( "dest" ), it.key().second );
398 
399  Q_NOWARN_DEPRECATED_PUSH
400  transformElem.setAttribute( QStringLiteral( "sourceTransform" ), it.value().sourceTransformId < 0 ? QString() : QgsDatumTransform::datumTransformToProj( it.value().sourceTransformId ) );
401  transformElem.setAttribute( QStringLiteral( "destTransform" ), it.value().destinationTransformId < 0 ? QString() : QgsDatumTransform::datumTransformToProj( it.value().destinationTransformId ) );
402  Q_NOWARN_DEPRECATED_POP
403 #endif
404  contextElem.appendChild( transformElem );
405  }
406 
407  element.appendChild( contextElem );
408  d->mLock.unlock();
409 }
410 
411 void QgsCoordinateTransformContext::readSettings()
412 {
413  d.detach();
414  d->mLock.lockForWrite();
415 
416  d->mSourceDestDatumTransforms.clear();
417 
418  QgsSettings settings;
419  settings.beginGroup( QStringLiteral( "/Projections" ) );
420  QStringList projectionKeys = settings.allKeys();
421 
422  //collect src and dest entries that belong together
423 #if PROJ_VERSION_MAJOR>=6
424  QMap< QPair< QgsCoordinateReferenceSystem, QgsCoordinateReferenceSystem >, QgsCoordinateTransformContextPrivate::OperationDetails > transforms;
425 #else
426  QMap< QPair< QString, QString >, QPair< int, int > > transforms;
427 #endif
428  QStringList::const_iterator pkeyIt = projectionKeys.constBegin();
429  for ( ; pkeyIt != projectionKeys.constEnd(); ++pkeyIt )
430  {
431 #if PROJ_VERSION_MAJOR>=6
432  if ( pkeyIt->contains( QLatin1String( "coordinateOp" ) ) )
433  {
434  QStringList split = pkeyIt->split( '/' );
435  QString srcAuthId, destAuthId;
436  if ( ! split.isEmpty() )
437  {
438  srcAuthId = split.at( 0 );
439  }
440  if ( split.size() > 1 )
441  {
442  destAuthId = split.at( 1 ).split( '_' ).at( 0 );
443  }
444 
445  if ( srcAuthId.isEmpty() || destAuthId.isEmpty() )
446  continue;
447 
448  const QString proj = settings.value( *pkeyIt ).toString();
449  const bool allowFallback = settings.value( QStringLiteral( "%1//%2_allowFallback" ).arg( srcAuthId, destAuthId ) ).toBool();
450  QgsCoordinateTransformContextPrivate::OperationDetails deets;
451  deets.operation = proj;
452  deets.allowFallback = allowFallback;
453  transforms[ qMakePair( QgsCoordinateReferenceSystem( srcAuthId ), QgsCoordinateReferenceSystem( destAuthId ) )] = deets;
454  }
455 #else
456  if ( pkeyIt->contains( QLatin1String( "srcTransform" ) ) || pkeyIt->contains( QLatin1String( "destTransform" ) ) )
457  {
458  QStringList split = pkeyIt->split( '/' );
459  QString srcAuthId, destAuthId;
460  if ( ! split.isEmpty() )
461  {
462  srcAuthId = split.at( 0 );
463  }
464  if ( split.size() > 1 )
465  {
466  destAuthId = split.at( 1 ).split( '_' ).at( 0 );
467  }
468 
469  QString proj = settings.value( *pkeyIt ).toString();
470  Q_NOWARN_DEPRECATED_PUSH
471  int datumId = QgsDatumTransform::projStringToDatumTransformId( proj );
472  Q_NOWARN_DEPRECATED_POP
473  if ( pkeyIt->contains( QLatin1String( "srcTransform" ) ) )
474  {
475  transforms[ qMakePair( srcAuthId, destAuthId )].first = datumId;
476  }
477  else if ( pkeyIt->contains( QLatin1String( "destTransform" ) ) )
478  {
479  transforms[ qMakePair( srcAuthId, destAuthId )].second = datumId;
480  }
481  }
482 #endif
483  }
484 
485  // add transforms to context
486  auto transformIt = transforms.constBegin();
487  for ( ; transformIt != transforms.constEnd(); ++transformIt )
488  {
489 #if PROJ_VERSION_MAJOR>=6
490  d->mSourceDestDatumTransforms.insert( transformIt.key(), transformIt.value() );
491 #else
492  d->mSourceDestDatumTransforms.insert( transformIt.key(), QgsDatumTransform::TransformPair( transformIt.value().first, transformIt.value().second ) );
493 #endif
494  }
495 
496  d->mLock.unlock();
497  settings.endGroup();
498 }
499 
500 void QgsCoordinateTransformContext::writeSettings()
501 {
502  QgsSettings settings;
503  settings.beginGroup( QStringLiteral( "/Projections" ) );
504  QStringList groupKeys = settings.allKeys();
505  QStringList::const_iterator groupKeyIt = groupKeys.constBegin();
506  for ( ; groupKeyIt != groupKeys.constEnd(); ++groupKeyIt )
507  {
508  if ( groupKeyIt->contains( QLatin1String( "srcTransform" ) ) || groupKeyIt->contains( QLatin1String( "destTransform" ) ) || groupKeyIt->contains( QLatin1String( "coordinateOp" ) ) )
509  {
510  settings.remove( *groupKeyIt );
511  }
512  }
513 
514  for ( auto transformIt = d->mSourceDestDatumTransforms.constBegin(); transformIt != d->mSourceDestDatumTransforms.constEnd(); ++transformIt )
515  {
516 #if PROJ_VERSION_MAJOR>=6
517  const QString srcAuthId = transformIt.key().first.authid();
518  const QString destAuthId = transformIt.key().second.authid();
519 #else
520  const QString srcAuthId = transformIt.key().first;
521  const QString destAuthId = transformIt.key().second;
522 #endif
523 
524  if ( srcAuthId.isEmpty() || destAuthId.isEmpty() )
525  continue; // not so nice, but alternative would be to shove whole CRS wkt into the settings values...
526 
527 #if PROJ_VERSION_MAJOR>=6
528  const QString proj = transformIt.value().operation;
529  const bool allowFallback = transformIt.value().allowFallback;
530  settings.setValue( srcAuthId + "//" + destAuthId + "_coordinateOp", proj );
531  settings.setValue( srcAuthId + "//" + destAuthId + "_allowFallback", allowFallback );
532 #else
533  int sourceDatumTransform = transformIt.value().sourceTransformId;
534  QString sourceDatumProj;
535  Q_NOWARN_DEPRECATED_PUSH
536  if ( sourceDatumTransform >= 0 )
537  sourceDatumProj = QgsDatumTransform::datumTransformToProj( sourceDatumTransform );
538  int destinationDatumTransform = transformIt.value().destinationTransformId;
539  QString destinationDatumProj;
540  if ( destinationDatumTransform >= 0 )
541  destinationDatumProj = QgsDatumTransform::datumTransformToProj( destinationDatumTransform );
542  Q_NOWARN_DEPRECATED_POP
543 
544  settings.setValue( srcAuthId + "//" + destAuthId + "_srcTransform", sourceDatumProj );
545  settings.setValue( srcAuthId + "//" + destAuthId + "_destTransform", destinationDatumProj );
546 #endif
547  }
548 
549  settings.endGroup();
550 }
QgsSettings::remove
void remove(const QString &key, QgsSettings::Section section=QgsSettings::NoSection)
Removes the setting key and any sub-settings of key in a section.
Definition: qgssettings.cpp:205
QgsCoordinateTransformContext
Contains information about the context in which a coordinate transform is executed.
Definition: qgscoordinatetransformcontext.h:58
QgsCoordinateTransformContext::removeSourceDestinationDatumTransform
Q_DECL_DEPRECATED void removeSourceDestinationDatumTransform(const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs)
Removes the source to destination datum transform pair for the specified sourceCrs and destinationCrs...
Definition: qgscoordinatetransformcontext.cpp:143
QgsSettings::endGroup
void endGroup()
Resets the group to what it was before the corresponding beginGroup() call.
Definition: qgssettings.cpp:97
QgsSettings::value
QVariant value(const QString &key, const QVariant &defaultValue=QVariant(), Section section=NoSection) const
Returns the value for setting key.
Definition: qgssettings.cpp:174
QgsReadWriteContext
The class is used as a container of context for various read/write operations on other objects.
Definition: qgsreadwritecontext.h:35
QgsCoordinateTransformContext::operator=
QgsCoordinateTransformContext & operator=(const QgsCoordinateTransformContext &rhs)
Assignment operator.
Definition: qgscoordinatetransformcontext.cpp:48
QgsCoordinateTransformContext::removeCoordinateOperation
void removeCoordinateOperation(const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs)
Removes the coordinate operation for the specified sourceCrs and destinationCrs.
Definition: qgscoordinatetransformcontext.cpp:148
QgsCoordinateReferenceSystem::WKT_PREFERRED
@ WKT_PREFERRED
Preferred format, matching the most recent WKT ISO standard. Currently an alias to WKT2_2019,...
Definition: qgscoordinatereferencesystem.h:679
qgscoordinatetransformcontext.h
crs
const QgsCoordinateReferenceSystem & crs
Definition: qgswfsgetfeature.cpp:51
QgsSettings::allKeys
QStringList allKeys() const
Returns a list of all keys, including subkeys, that can be read using the QSettings object.
Definition: qgssettings.cpp:111
QgsDatumTransform::TransformPair
Contains datum transform information.
Definition: qgsdatumtransform.h:55
QgsCoordinateTransformContext::~QgsCoordinateTransformContext
~QgsCoordinateTransformContext()
qgscoordinatetransformcontext_p.h
QgsSettings
This class is a composition of two QSettings instances:
Definition: qgssettings.h:62
QgsCoordinateTransformContext::operator==
bool operator==(const QgsCoordinateTransformContext &rhs) const
Definition: qgscoordinatetransformcontext.cpp:54
QgsCoordinateReferenceSystem::readXml
bool readXml(const QDomNode &node)
Restores state from the given DOM node.
Definition: qgscoordinatereferencesystem.cpp:2018
QgsDatumTransform::TransformPair::sourceTransformId
int sourceTransformId
ID for the datum transform to use when projecting from the source CRS.
Definition: qgsdatumtransform.h:70
QgsDatumTransform::TransformPair::destinationTransformId
int destinationTransformId
ID for the datum transform to use when projecting to the destination CRS.
Definition: qgsdatumtransform.h:76
QgsCoordinateTransformContext::readSettings
void readSettings()
Reads the context's state from application settings.
Definition: qgscoordinatetransformcontext.cpp:411
QgsCoordinateTransformContext::addCoordinateOperation
bool addCoordinateOperation(const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs, const QString &coordinateOperationProjString, bool allowFallback=true)
Adds a new coordinateOperationProjString to use when projecting coordinates from the specified source...
Definition: qgscoordinatetransformcontext.cpp:123
Q_NOWARN_DEPRECATED_POP
#define Q_NOWARN_DEPRECATED_POP
Definition: qgis.h:797
QgsCoordinateTransformContext::allowFallbackTransform
bool allowFallbackTransform(const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination) const
Returns true if approximate "ballpark" transforms may be used when transforming between a source and ...
Definition: qgscoordinatetransformcontext.cpp:217
QgsCoordinateTransformContext::coordinateOperations
QMap< QPair< QString, QString >, QString > coordinateOperations() const
Returns the stored mapping for source to destination CRS pairs to associated coordinate operation to ...
Definition: qgscoordinatetransformcontext.cpp:89
QgsCoordinateTransformContext::readXml
bool readXml(const QDomElement &element, const QgsReadWriteContext &context, QStringList &missingTransforms)
Reads the context's state from a DOM element.
Definition: qgscoordinatetransformcontext.cpp:269
QgsCoordinateTransformContext::clear
void clear()
Clears all stored transform information from the context.
Definition: qgscoordinatetransformcontext.cpp:67
QgsCoordinateReferenceSystem::authid
QString authid() const
Returns the authority identifier for the CRS.
Definition: qgscoordinatereferencesystem.cpp:1321
QgsCoordinateTransformContext::sourceDestinationDatumTransforms
Q_DECL_DEPRECATED QMap< QPair< QString, QString >, QgsDatumTransform::TransformPair > sourceDestinationDatumTransforms() const
Returns the stored mapping for source to destination CRS pairs to associated datum transforms to use.
Definition: qgscoordinatetransformcontext.cpp:76
QgsCoordinateReferenceSystem::toWkt
QString toWkt(WktVariant variant=WKT1_GDAL, bool multiline=false, int indentationWidth=4) const
Returns a WKT representation of this CRS.
Definition: qgscoordinatereferencesystem.cpp:1954
QgsCoordinateReferenceSystem::isValid
bool isValid() const
Returns whether this CRS is correctly initialized and usable.
Definition: qgscoordinatereferencesystem.cpp:924
qgscoordinatetransform.h
QgsCoordinateTransformContext::addSourceDestinationDatumTransform
Q_DECL_DEPRECATED bool addSourceDestinationDatumTransform(const QgsCoordinateReferenceSystem &sourceCrs, const QgsCoordinateReferenceSystem &destinationCrs, int sourceTransformId, int destinationTransformId)
Adds a new sourceTransform and destinationTransform to use when projecting coordinates from the speci...
Definition: qgscoordinatetransformcontext.cpp:106
QgsSettings::setValue
void setValue(const QString &key, const QVariant &value, QgsSettings::Section section=QgsSettings::NoSection)
Sets the value of setting key to value.
Definition: qgssettings.cpp:289
QgsCoordinateReferenceSystem
This class represents a coordinate reference system (CRS).
Definition: qgscoordinatereferencesystem.h:206
QgsDatumTransform::projStringToDatumTransformId
static Q_DECL_DEPRECATED int projStringToDatumTransformId(const QString &string)
Returns the datum transform ID corresponding to a specified proj string.
Definition: qgsdatumtransform.cpp:214
QgsSettings::beginGroup
void beginGroup(const QString &prefix, QgsSettings::Section section=QgsSettings::NoSection)
Appends prefix to the current group.
Definition: qgssettings.cpp:87
QgsCoordinateTransformContext::writeXml
void writeXml(QDomElement &element, const QgsReadWriteContext &context) const
Writes the context's state to a DOM element.
Definition: qgscoordinatetransformcontext.cpp:371
QgsCoordinateTransformContext::calculateCoordinateOperation
QString calculateCoordinateOperation(const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination) const
Returns the Proj coordinate operation string to use when transforming from the specified source CRS t...
Definition: qgscoordinatetransformcontext.cpp:195
qgsprojutils.h
qgssettings.h
QgsCoordinateTransformContext::calculateDatumTransforms
Q_DECL_DEPRECATED QgsDatumTransform::TransformPair calculateDatumTransforms(const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination) const
Returns the pair of source and destination datum transforms to use for a transform from the specified...
Definition: qgscoordinatetransformcontext.cpp:171
crsToKey
QString crsToKey(const QgsCoordinateReferenceSystem &crs)
Definition: qgscoordinatetransformcontext.cpp:24
QgsCoordinateTransformContext::mustReverseCoordinateOperation
bool mustReverseCoordinateOperation(const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination) const
Returns true if the coordinate operation returned by calculateCoordinateOperation() for the source to...
Definition: qgscoordinatetransformcontext.cpp:239
QgsCoordinateTransformContext::hasTransform
bool hasTransform(const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination) const
Returns true if the context has a valid coordinate operation to use when transforming from the specif...
Definition: qgscoordinatetransformcontext.cpp:157
Q_NOWARN_DEPRECATED_PUSH
#define Q_NOWARN_DEPRECATED_PUSH
Definition: qgis.h:796
QgsDatumTransform::datumTransformToProj
static Q_DECL_DEPRECATED QString datumTransformToProj(int datumTransformId)
Returns a proj string representing the specified datumTransformId datum transform ID.
Definition: qgsdatumtransform.cpp:162
QgsCoordinateTransformContext::writeSettings
void writeSettings()
Write the context's state to application settings.
Definition: qgscoordinatetransformcontext.cpp:500
QgsCoordinateTransformContext::QgsCoordinateTransformContext
QgsCoordinateTransformContext()
Constructor for QgsCoordinateTransformContext.
Definition: qgscoordinatetransformcontext.cpp:38
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