Cleanup QgsCoordinateReferenceSystem WKT enum

- alias WKT_2018* to new WKT_2019* values, since the spec is actually 2019, not 2018 - add WKT_PREFERRED value which currently aliases to WKT2_2019, but can be changed if/when future bumps to the WKT spec happen - add WKT_PREFERRED_GDAL which should be used whenever a CRS is exported to WKT for use with GDAL API. Aliases to WKT2_2019 currently, but can be changed if/when a new spec is released and GDAL supports it
qgis · Apr 23, 2020 · 5b6589f · 5b6589f
1 parent 5d45b71
commit 5b6589f
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Showing 36 changed files with 95 additions and 81 deletions.
diff --git a/python/core/auto_generated/qgscoordinatereferencesystem.sip.in b/python/core/auto_generated/qgscoordinatereferencesystem.sip.in
@@ -718,6 +718,12 @@ Returns the ellipsoid acronym for the ellipsoid used by the CRS.
       WKT2_2015_SIMPLIFIED,
       WKT2_2018,
       WKT2_2018_SIMPLIFIED,
+      WKT2_2019,
+      WKT2_2019_SIMPLIFIED,
+
+      WKT_PREFERRED,
+      WKT_PREFERRED_SIMPLIFIED,
+      WKT_PREFERRED_GDAL,
     };
 
     QString toWkt( WktVariant variant = WKT1_GDAL, bool multiline = false, int indentationWidth = 4 ) const;

diff --git a/python/plugins/processing/algs/gdal/GdalUtils.py b/python/plugins/processing/algs/gdal/GdalUtils.py
@@ -439,7 +439,7 @@ def gdal_crs_string(crs):
 
         if QgsProjUtils.projVersionMajor() >= 6:
             # use WKT
-            return crs.toWkt(QgsCoordinateReferenceSystem.WKT2_2018)
+            return crs.toWkt(QgsCoordinateReferenceSystem.WKT_PREFERRED_GDAL)
 
         # fallback to proj4 string, stripping out newline characters
         return crs.toProj().replace('\n', ' ').replace('\r', ' ')
diff --git a/src/analysis/processing/qgsalgorithmrasterize.cpp b/src/analysis/processing/qgsalgorithmrasterize.cpp
@@ -173,7 +173,7 @@ QVariantMap QgsRasterizeAlgorithm::processAlgorithm( const QVariantMap &paramete
     throw QgsProcessingException( QObject::tr( "Error creating GDAL output layer" ) );
   }
 
-  GDALSetProjection( hOutputDataset.get(), context.project()->crs().toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ).toLatin1().constData() );
+  GDALSetProjection( hOutputDataset.get(), context.project()->crs().toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ).toLatin1().constData() );
   double geoTransform[6];
   geoTransform[0] = extent.xMinimum();
   geoTransform[1] = mapUnitsPerPixel;

diff --git a/src/analysis/raster/qgsalignraster.cpp b/src/analysis/raster/qgsalignraster.cpp
@@ -397,7 +397,7 @@ int QgsAlignRaster::suggestedReferenceLayer() const
   // would be a better a choice to more accurately compute areas?
   // (Why earth is not flat???)
   QgsCoordinateReferenceSystem destCRS( QStringLiteral( "EPSG:4326" ) );
-  QString destWkt = destCRS.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 );
+  QString destWkt = destCRS.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL );
 
   const auto constMRasters = mRasters;
   for ( const Item &raster : constMRasters )

diff --git a/src/analysis/raster/qgsrastercalculator.cpp b/src/analysis/raster/qgsrastercalculator.cpp
@@ -153,7 +153,7 @@ QgsRasterCalculator::Result QgsRasterCalculator::processCalculation( QgsFeedback
     return CreateOutputError;
   }
 
-  GDALSetProjection( outputDataset.get(), mOutputCrs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ).toLocal8Bit().data() );
+  GDALSetProjection( outputDataset.get(), mOutputCrs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ).toLocal8Bit().data() );
   GDALRasterBandH outputRasterBand = GDALGetRasterBand( outputDataset.get(), 1 );
 
   float outputNodataValue = -FLT_MAX;
@@ -529,7 +529,7 @@ QgsRasterCalculator::Result QgsRasterCalculator::processCalculationGPU( std::uni
       return CreateOutputError;
     }
 
-    GDALSetProjection( outputDataset.get(), mOutputCrs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ).toLocal8Bit().data() );
+    GDALSetProjection( outputDataset.get(), mOutputCrs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ).toLocal8Bit().data() );
 
 
     GDALRasterBandH outputRasterBand = GDALGetRasterBand( outputDataset.get(), 1 );

diff --git a/src/app/dwg/qgsdwgimporter.cpp b/src/app/dwg/qgsdwgimporter.cpp
@@ -77,7 +77,7 @@ QgsDwgImporter::QgsDwgImporter( const QString &database, const QgsCoordinateRefe
 {
   QgsDebugCall;
 
-  QString crswkt( crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ) );
+  QString crswkt( crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ) );
   mCrsH = OSRNewSpatialReference( crswkt.toLocal8Bit().constData() );
   QgsDebugMsg( QStringLiteral( "CRS %1[%2]: %3" ).arg( mCrs ).arg( ( qint64 ) mCrsH, 0, 16 ).arg( crswkt ) );
 }

diff --git a/src/app/qgsalignrasterdialog.cpp b/src/app/qgsalignrasterdialog.cpp
@@ -196,7 +196,7 @@ void QgsAlignRasterDialog::updateParametersFromReferenceLayer()
   {
     QgsCoordinateReferenceSystem refCRS( refInfo.crs() );
     if ( refCRS != mCrsSelector->crs() )
-      customCRSWkt = mCrsSelector->crs( ).toWkt( QgsCoordinateReferenceSystem::WKT2_2018 );
+      customCRSWkt = mCrsSelector->crs( ).toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL );
   }
 
   if ( mChkCustomCellSize->isChecked() )
@@ -313,7 +313,7 @@ void QgsAlignRasterDialog::referenceLayerChanged()
 
 void QgsAlignRasterDialog::destinationCrsChanged()
 {
-  if ( mCrsSelector->crs().toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ) == mAlign->destinationCrs() )
+  if ( mCrsSelector->crs().toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ) == mAlign->destinationCrs() )
     return;
 
   int index = mCboReferenceLayer->currentIndex();

diff --git a/src/app/qgscustomprojectiondialog.cpp b/src/app/qgscustomprojectiondialog.cpp
@@ -132,8 +132,8 @@ void QgsCustomProjectionDialog::populateList()
         crs.createFromProj( parameters );
 
       mExistingCRSnames[id] = name;
-      const QString actualWkt = crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, false );
-      const QString actualWktFormatted = crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, true );
+      const QString actualWkt = crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, false );
+      const QString actualWktFormatted = crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, true );
       const QString actualProj = crs.toProj();
       mExistingCRSwkt[id] = wkt.isEmpty() ? QString() : actualWkt;
       mExistingCRSproj[id] = wkt.isEmpty() ? actualProj : QString();
@@ -273,7 +273,7 @@ bool QgsCustomProjectionDialog::saveCrs( QgsCoordinateReferenceSystem crs, const
           + ",ellipsoid_acronym=" + ( !ellipsoidAcronym.isEmpty() ? QgsSqliteUtils::quotedString( ellipsoidAcronym ) : QStringLiteral( "''" ) )
           + ",parameters=" + ( !crs.toProj().isEmpty() ? QgsSqliteUtils::quotedString( crs.toProj() ) : QStringLiteral( "''" ) )
           + ",is_geo=0" // <--shamelessly hard coded for now
-          + ",wkt=" + ( format == QgsCoordinateReferenceSystem::FormatWkt ? QgsSqliteUtils::quotedString( crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, false ) ) : QStringLiteral( "''" ) )
+          + ",wkt=" + ( format == QgsCoordinateReferenceSystem::FormatWkt ? QgsSqliteUtils::quotedString( crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, false ) ) : QStringLiteral( "''" ) )
           + " where srs_id=" + QgsSqliteUtils::quotedString( id )
           ;
     QgsDebugMsgLevel( sql, 4 );
@@ -298,7 +298,7 @@ bool QgsCustomProjectionDialog::saveCrs( QgsCoordinateReferenceSystem crs, const
     if ( result != SQLITE_OK )
       return false;
   }
-  mExistingCRSwkt[id] = format == QgsCoordinateReferenceSystem::FormatWkt ? crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, false ) : QString();
+  mExistingCRSwkt[id] = format == QgsCoordinateReferenceSystem::FormatWkt ? crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, false ) : QString();
   mExistingCRSproj[id] = format == QgsCoordinateReferenceSystem::FormatProj ? crs.toProj() : QString();
   mExistingCRSnames[id] = name;
 
@@ -426,12 +426,12 @@ void QgsCustomProjectionDialog::pbnCopyCRS_clicked()
     }
 
     whileBlocking( mFormatComboBox )->setCurrentIndex( mFormatComboBox->findData( static_cast< int >( QgsCoordinateReferenceSystem::FormatWkt ) ) );
-    teParameters->setPlainText( srs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, true ) );
-    mDefinitions[leNameList->currentIndex().row()].wkt = srs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, false );
+    teParameters->setPlainText( srs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, true ) );
+    mDefinitions[leNameList->currentIndex().row()].wkt = srs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, false );
     mDefinitions[leNameList->currentIndex().row()].proj.clear();
 
-    leNameList->currentItem()->setText( QgisCrsParametersColumn, srs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, false ) );
-    leNameList->currentItem()->setData( 0, FormattedWktRole, srs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018, true ) );
+    leNameList->currentItem()->setText( QgisCrsParametersColumn, srs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, false ) );
+    leNameList->currentItem()->setData( 0, FormattedWktRole, srs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED, true ) );
   }
 }
 
@@ -491,7 +491,7 @@ void QgsCustomProjectionDialog::buttonBox_accepted()
         {
           ref = QStringLiteral( "ID[\"%1\",%2]" ).arg( authparts.at( 0 ), authparts.at( 1 ) );
         }
-        if ( !ref.isEmpty() && crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ).contains( ref ) )
+        if ( !ref.isEmpty() && crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED ).contains( ref ) )
         {
           QMessageBox::warning( this, tr( "Custom Coordinate Reference System" ),
                                 tr( "Cannot save '%1' — the definition is equivalent to %2.\n\n(Try removing \"%3\" from the WKT definition.)" ).arg( def.name, crs.authid(), ref ) );
@@ -727,7 +727,7 @@ void QgsCustomProjectionDialog::formatChanged()
         {
           const QByteArray multiLineOption = QStringLiteral( "MULTILINE=YES" ).toLocal8Bit();
           const char *const options[] = {multiLineOption.constData(), nullptr};
-          newFormatString = QString( proj_as_wkt( pjContext, crs.get(), PJ_WKT2_2018, options ) );
+          newFormatString = QString( proj_as_wkt( pjContext, crs.get(), PJ_WKT2_2019, options ) );
         }
       }
 #else

diff --git a/src/core/expression/qgsexpressioncontextutils.cpp b/src/core/expression/qgsexpressioncontextutils.cpp
@@ -391,7 +391,7 @@ QgsExpressionContextScope *QgsExpressionContextUtils::mapSettingsScope( const Qg
   scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_acronym" ), mapSettings.destinationCrs().projectionAcronym(), true ) );
   scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_ellipsoid" ), mapSettings.destinationCrs().ellipsoidAcronym(), true ) );
   scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_proj4" ), mapSettings.destinationCrs().toProj(), true ) );
-  scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_wkt" ), mapSettings.destinationCrs().toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ), true ) );
+  scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_wkt" ), mapSettings.destinationCrs().toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED ), true ) );
 
   // IMPORTANT: ANY CHANGES HERE ALSO NEED TO BE MADE TO QgsLayoutItemMap::createExpressionContext()
   // (rationale is described in QgsLayoutItemMap::createExpressionContext() )

diff --git a/src/core/layout/qgslayoutexporter.cpp b/src/core/layout/qgslayoutexporter.cpp
@@ -1592,7 +1592,7 @@ bool QgsLayoutExporter::georeferenceOutputPrivate( const QString &file, QgsLayou
     }
 
     if ( t )
-      GDALSetProjection( outputDS.get(), map->crs().toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ).toLocal8Bit().constData() );
+      GDALSetProjection( outputDS.get(), map->crs().toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ).toLocal8Bit().constData() );
   }
   CPLSetConfigOption( "GDAL_PDF_DPI", nullptr );
 

diff --git a/src/core/layout/qgslayoutitemmap.cpp b/src/core/layout/qgslayoutitemmap.cpp
@@ -1535,7 +1535,7 @@ QgsExpressionContext QgsLayoutItemMap::createExpressionContext() const
   scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_acronym" ), mapCrs.projectionAcronym(), true ) );
   scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_ellipsoid" ), mapCrs.ellipsoidAcronym(), true ) );
   scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_proj4" ), mapCrs.toProj(), true ) );
-  scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_wkt" ), mapCrs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ), true ) );
+  scope->addVariable( QgsExpressionContextScope::StaticVariable( QStringLiteral( "map_crs_wkt" ), mapCrs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED ), true ) );
 
   QVariantList layersIds;
   QVariantList layers;

diff --git a/src/core/providers/gdal/qgsgdaldataitems.cpp b/src/core/providers/gdal/qgsgdaldataitems.cpp
@@ -61,7 +61,7 @@ bool QgsGdalLayerItem::setCrs( const QgsCoordinateReferenceSystem &crs )
   if ( !hDS )
     return false;
 
-  QString wkt = crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 );
+  QString wkt = crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL );
   if ( GDALSetProjection( hDS.get(), wkt.toLocal8Bit().data() ) != CE_None )
   {
     QgsDebugMsg( QStringLiteral( "Could not set CRS" ) );

diff --git a/src/core/providers/gdal/qgsgdalprovider.cpp b/src/core/providers/gdal/qgsgdalprovider.cpp
@@ -2951,7 +2951,7 @@ QgsGdalProvider *QgsGdalProviderMetadata::createRasterDataProvider(
   }
 
   GDALSetGeoTransform( dataset.get(), geoTransform );
-  GDALSetProjection( dataset.get(), crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ).toLocal8Bit().data() );
+  GDALSetProjection( dataset.get(), crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ).toLocal8Bit().data() );
 
   QgsDataProvider::ProviderOptions providerOptions;
   return new QgsGdalProvider( uri, providerOptions, true, dataset.release() );

diff --git a/src/core/providers/memory/qgsmemoryprovider.cpp b/src/core/providers/memory/qgsmemoryprovider.cpp
@@ -256,7 +256,7 @@ QString QgsMemoryProvider::dataSourceUri( bool expandAuthConfig ) const
     }
     else
     {
-      crsDef = QStringLiteral( "wkt:%1" ).arg( mCrs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ) );
+      crsDef = QStringLiteral( "wkt:%1" ).arg( mCrs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED ) );
     }
     query.addQueryItem( QStringLiteral( "crs" ), crsDef );
   }

diff --git a/src/core/providers/ogr/qgsogrprovider.cpp b/src/core/providers/ogr/qgsogrprovider.cpp
@@ -3543,7 +3543,7 @@ bool QgsOgrProviderUtils::createEmptyDataSource( const QString &uri,
     mySpatialRefSys.validate();
   }
 
-  QString myWkt = mySpatialRefSys.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 );
+  QString myWkt = mySpatialRefSys.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL );
 
   if ( !myWkt.isNull()  &&  myWkt.length() != 0 )
   {

diff --git a/src/core/qgsabstractgeopdfexporter.cpp b/src/core/qgsabstractgeopdfexporter.cpp
@@ -394,7 +394,7 @@ QString QgsAbstractGeoPdfExporter::createCompositionXml( const QList<ComponentLa
       }
       else
       {
-        srs.appendChild( doc.createTextNode( section.crs.toWkt( QgsCoordinateReferenceSystem::WKT2_2018 ) ) );
+        srs.appendChild( doc.createTextNode( section.crs.toWkt( QgsCoordinateReferenceSystem::WKT_PREFERRED_GDAL ) ) );
       }
       georeferencing.appendChild( srs );
     }

diff --git a/src/core/qgscoordinatereferencesystem.cpp b/src/core/qgscoordinatereferencesystem.cpp
@@ -1296,10 +1296,10 @@ QString QgsCoordinateReferenceSystem::userFriendlyIdentifier( IdentifierType typ
     return description();
   else if ( type == ShortString )
     return QObject::tr( "Unknown CRS" );
-  else if ( !toWkt( WKT2_2018 ).isEmpty() )
+  else if ( !toWkt( WKT_PREFERRED ).isEmpty() )
     return QObject::tr( "Unknown CRS: %1" ).arg(
-             type == MediumString ? ( toWkt( WKT2_2018 ).left( 50 ) + QString( QChar( 0x2026 ) ) )
-             : toWkt( WKT2_2018 ) );
+             type == MediumString ? ( toWkt( WKT_PREFERRED ).left( 50 ) + QString( QChar( 0x2026 ) ) )
+             : toWkt( WKT_PREFERRED ) );
   else if ( !toProj().isEmpty() )
     return QObject::tr( "Unknown CRS: %1" ).arg( type == MediumString ? ( toProj().left( 50 ) + QString( QChar( 0x2026 ) ) )
            : toProj() );
@@ -1889,7 +1889,7 @@ bool QgsCoordinateReferenceSystem::operator==( const QgsCoordinateReferenceSyste
   if ( ( !d->mAuthId.isEmpty() || !srs.d->mAuthId.isEmpty() ) )
     return d->mAuthId == srs.d->mAuthId;
 
-  return toWkt( WKT2_2018 ) == srs.toWkt( WKT2_2018 );
+  return toWkt( WKT_PREFERRED ) == srs.toWkt( WKT_PREFERRED );
 }
 
 bool QgsCoordinateReferenceSystem::operator!=( const QgsCoordinateReferenceSystem &srs ) const
@@ -1917,11 +1917,11 @@ QString QgsCoordinateReferenceSystem::toWkt( WktVariant variant, bool multiline,
       case WKT2_2015_SIMPLIFIED:
         type = PJ_WKT2_2015_SIMPLIFIED;
         break;
-      case WKT2_2018:
-        type = PJ_WKT2_2018;
+      case WKT2_2019:
+        type = PJ_WKT2_2019;
         break;
-      case WKT2_2018_SIMPLIFIED:
-        type = PJ_WKT2_2018_SIMPLIFIED;
+      case WKT2_2019_SIMPLIFIED:
+        type = PJ_WKT2_2019_SIMPLIFIED;
         break;
     }
 
@@ -2049,7 +2049,7 @@ bool QgsCoordinateReferenceSystem::writeXml( QDomNode &node, QDomDocument &doc )
   QDomElement srsElement = doc.createElement( QStringLiteral( "spatialrefsys" ) );
 
   QDomElement wktElement = doc.createElement( QStringLiteral( "wkt" ) );
-  wktElement.appendChild( doc.createTextNode( toWkt( WKT2_2018 ) ) );
+  wktElement.appendChild( doc.createTextNode( toWkt( WKT_PREFERRED ) ) );
   srsElement.appendChild( wktElement );
 
   QDomElement proj4Element = doc.createElement( QStringLiteral( "proj4" ) );
@@ -2189,7 +2189,7 @@ void QgsCoordinateReferenceSystem::debugPrint()
   QgsDebugMsg( "* Valid : " + ( d->mIsValid ? QString( "true" ) : QString( "false" ) ) );
   QgsDebugMsg( "* SrsId : " + QString::number( d->mSrsId ) );
   QgsDebugMsg( "* Proj4 : " + toProj() );
-  QgsDebugMsg( "* WKT   : " + toWkt( WKT2_2018 ) );
+  QgsDebugMsg( "* WKT   : " + toWkt( WKT_PREFERRED ) );
   QgsDebugMsg( "* Desc. : " + d->mDescription );
   if ( mapUnits() == QgsUnitTypes::DistanceMeters )
   {
@@ -2233,7 +2233,7 @@ long QgsCoordinateReferenceSystem::saveAsUserCrs( const QString &name, Format na
   {
     proj4String = toProj();
   }
-  QString wktString = toWkt( WKT2_2018 );
+  QString wktString = toWkt( WKT_PREFERRED );
 
   // ellipsoid acroynym column is incorrectly marked as not null in many crs database instances,
   // hack around this by using an empty string instead
@@ -3565,7 +3565,7 @@ void QgsCoordinateReferenceSystem::pushRecentCoordinateReferenceSystem( const Qg
   {
     authids << c.authid();
     proj << c.toProj();
-    wkt << c.toWkt( WKT2_2018 );
+    wkt << c.toWkt( WKT_PREFERRED );
   }
 
   QgsSettings settings;

diff --git a/src/core/qgscoordinatereferencesystem.h b/src/core/qgscoordinatereferencesystem.h
@@ -664,8 +664,14 @@ class CORE_EXPORT QgsCoordinateReferenceSystem
       WKT1_ESRI, //!< WKT1 as traditionally output by ESRI software, deriving from OGC 99-049.
       WKT2_2015, //!< Full WKT2 string, conforming to ISO 19162:2015(E) / OGC 12-063r5 with all possible nodes and new keyword names.
       WKT2_2015_SIMPLIFIED, //!< Same as WKT2_2015 with the following exceptions: UNIT keyword used. ID node only on top element. No ORDER element in AXIS element. PRIMEM node omitted if it is Greenwich.  ELLIPSOID.UNIT node omitted if it is UnitOfMeasure::METRE. PARAMETER.UNIT / PRIMEM.UNIT omitted if same as AXIS. AXIS.UNIT omitted and replaced by a common GEODCRS.UNIT if they are all the same on all axis.
-      WKT2_2018, //!< Full WKT2 string, conforming to ISO 19162:2018 / OGC 18-010, with all possible nodes and new keyword names. Non-normative list of differences: WKT2_2018 uses GEOGCRS / BASEGEOGCRS keywords for GeographicCRS.
-      WKT2_2018_SIMPLIFIED, //!< WKT2_2018 with the simplification rule of WKT2_SIMPLIFIED
+      WKT2_2018, //!< Alias for WKT2_2019
+      WKT2_2018_SIMPLIFIED, //!< Alias for WKT2_2019_SIMPLIFIED
+      WKT2_2019 = WKT2_2018, //!< Full WKT2 string, conforming to ISO 19162:2019 / OGC 18-010, with all possible nodes and new keyword names. Non-normative list of differences: WKT2_2019 uses GEOGCRS / BASEGEOGCRS keywords for GeographicCRS.
+      WKT2_2019_SIMPLIFIED = WKT2_2018_SIMPLIFIED, //!< WKT2_2019 with the simplification rule of WKT2_SIMPLIFIED
+
+      WKT_PREFERRED = WKT2_2019, //!< Preferred format, matching the most recent WKT ISO standard. Currently an alias to WKT2_2019, but may change in future versions.
+      WKT_PREFERRED_SIMPLIFIED = WKT2_2019_SIMPLIFIED, //!< Preferred simplified format, matching the most recent WKT ISO standard. Currently an alias to WKT2_2019_SIMPLIFIED, but may change in future versions.
+      WKT_PREFERRED_GDAL = WKT2_2019, //!< Preferred format for conversion of CRS to WKT for use with the GDAL library.
     };
 
     /**

diff --git a/src/core/qgscoordinatereferencesystem_p.h b/src/core/qgscoordinatereferencesystem_p.h
@@ -178,6 +178,8 @@ class QgsCoordinateReferenceSystemPrivate : public QSharedData
 
     mutable QString mProj4;
 
+    mutable QString mWkt
+
     //! True if presence of an inverted axis needs to be recalculated
     mutable bool mAxisInvertedDirty = false;