Remove support for disabling OTF reprojection

Because
- OTF reprojection is mature and stable
- Should be no cost when not required - transforms are shortcut
when not required
- Reduces code complexity
- Canvas OTF support was being incorrectly used as a flag for
whether measurements should be made in ellipsoidal mode. Instead
the project's ellipsoid setting should be checked for this.
- Should simplify behavior for new users

Author: nyalldawson

doc/api_break.dox

@@ -1257,6 +1257,12 @@ QgsLayerTreeNode        {#qgis_api_break_3_0_QgsLayerTreeNode}
 - readXml() does not resolve layers from the layer IDs anymore. Call resolveReferences() or use readXml() override with QgsProject as the second argument.
 
 
+QgsLayerTreeMapCanvasBridge        {#qgis_api_break_3_0_QgsLayerTreeMapCanvasBridge}
+-----------------
+
+- setAutoEnableCrsTransform() and autoEnableCrsTransform() were removed. CRS transformation is now always enabled.
+
+
 QgsLayerTreeModel        {#qgis_api_break_3_0_QgsLayerTreeMode}
 -----------------
 
@@ -1315,6 +1321,7 @@ QgsMapCanvas        {#qgis_api_break_3_0_QgsMapCanvas}
 - setProgress() signal has been removed. It was not emitted since 2.0.
 - enableOverviewMode() and updateOverview() have been removed. Map canvas does not keep pointer to overview canvas anymore. Use QgsLayerTreeMapCanvasBridge::setOverviewCanvas() to set up updates of overview canvas together with main canvas.
 - the duplicate mapToolSet signal with a single QgsMapTool argument has been removed. Use the signal with arguments for new and old map tool instead.
+- setCrsTransformEnabled(), hasCrsTransformEnabled(), hasCrsTransformEnabledChanged() were removed. CRS transformation is now always enabled.
 
 QgsMapCanvasItem        {#qgis_api_break_3_0_QgsMapCanvasItem}
 ----------------
@@ -1354,6 +1361,7 @@ QgsMapOverviewCanvas        {#qgis_api_break_3_0_QgsMapOverviewCanvas}
 
 - layerSet() and setLayerSet() have been replaced by layers() and setLayers() which work with list of layers instead of layer IDs
 - destinationSrsChanged() was renamed to destinationCrsChanged()
+- hasCrsTransformEnabled() was removed. CRS transformation is now always enabled.
 
 
 QgsMapRenderer        {#qgis_api_break_3_0_QgsMapRenderer}
@@ -1421,6 +1429,7 @@ QgsMapSettings        {#qgis_api_break_3_0_QgsMapSettings}
 be returned instead of a null pointer if no transformation is required.
 - destinationCrs() now returns a copy instead of a reference to the CRS. This has no effect on PyQGIS code, but c++
 plugins calling this method will need to be updated.
+- setCrsTransformEnabled() and hasCrsTransformEnabled() were removed. CRS transformation is now always enabled.
 
 
 QgsMarkerSymbolLayer        {#qgis_api_break_3_0_QgsMarkerSymbolLayer}
@@ -1896,6 +1905,12 @@ QgsTolerance        {#qgis_api_break_3_0_QgsTolerance}
 - The MapUnits UnitType was removed. Use LayerUnits or ProjectUnits instead.
 
 
+QgsTracer        {#qgis_api_break_3_0_QgsTracer}
+---------
+
+- hasCrsTransformEnabled() and setCrsTransformEnabled() were removed. CRS transformation is now always enabled when required.
+
+
 QgsTreeWidgetItem        {#qgis_api_break_3_0_QgsTreeWidgetItem}
 -----------------
 

python/core/qgsmapsettings.sip

@@ -83,11 +83,6 @@ class QgsMapSettings
      */
     void setCustomRenderFlags( const QString& customRenderFlags );
 
-    //! sets whether to use projections for this layer set
-    void setCrsTransformEnabled( bool enabled );
-    //! returns true if projections are enabled for this layer set
-    bool hasCrsTransformEnabled() const;
-
     //! sets destination coordinate reference system
     void setDestinationCrs( const QgsCoordinateReferenceSystem& crs );
     //! returns CRS of destination coordinate reference system

python/core/qgstracer.sip

@@ -20,11 +20,6 @@ class QgsTracer : QObject
     //! Set layers used for tracing
     void setLayers( const QList<QgsVectorLayer*>& layers );
 
-    //! Return true if reprojection to destination CRS is enabled
-    bool hasCrsTransformEnabled() const;
-    //! Set whether to do reprojection to destination CRS
-    void setCrsTransformEnabled( bool enabled );
-
     //! Get CRS used for tracing
     QgsCoordinateReferenceSystem destinationCrs() const;
     //! Set CRS used for tracing

python/gui/layertree/qgslayertreemapcanvasbridge.sip

@@ -45,11 +45,6 @@ class QgsLayerTreeMapCanvasBridge : QObject
     void setAutoSetupOnFirstLayer( bool enabled );
     bool autoSetupOnFirstLayer() const;
 
-    //! if enabled, will automatically turn on on-the-fly reprojection of layers if a layer
-    //! with different source CRS is added
-    void setAutoEnableCrsTransform( bool enabled );
-    bool autoEnableCrsTransform() const;
-
   public slots:
     void setHasCustomLayerOrder( bool state );
     void setCustomLayerOrder( const QStringList& order );

python/gui/qgsmapcanvas.sip

@@ -36,10 +36,6 @@ class QgsMapCanvas : QGraphicsView
     //! @note added in 2.4
     const QgsMapSettings& mapSettings() const /KeepReference/;
 
-    //! sets whether to use projections for this layer set
-    //! @note added in 2.4
-    void setCrsTransformEnabled( bool enabled );
-
     //! sets destination coordinate reference system
     //! @note added in 2.4
     void setDestinationCrs( const QgsCoordinateReferenceSystem& crs );
@@ -360,9 +356,6 @@ class QgsMapCanvas : QGraphicsView
     //! State of render suppression flag
     bool renderFlag();
 
-    //! A simple helper method to find out if on the fly projections are enabled or not
-    bool hasCrsTransformEnabled();
-
     //! stop rendering (if there is any right now)
     //! @note added in 2.4
     void stopRendering();
@@ -454,10 +447,6 @@ class QgsMapCanvas : QGraphicsView
     //! Emitted when zoom next status changed
     void zoomNextStatusChanged( bool );
 
-    //! Emitted when on-the-fly projection has been turned on/off
-    //! @note added in 2.4
-    void hasCrsTransformEnabledChanged( bool flag );
-
     //! Emitted when map CRS has changed
     //! @note added in 2.4
     void destinationCrsChanged();

python/gui/qgsmapoverviewcanvas.sip

@@ -32,9 +32,6 @@ class QgsMapOverviewCanvas : QWidget
     //! used for overview canvas to reflect changed extent in main map canvas
     void drawExtentRect();
 
-    // ### QGIS 3: rename so it does not look like getter, make protected
-    void hasCrsTransformEnabled( bool flag );
-
     // ### QGIS 3: make protected
     //! Should be called when the canvas destination CRS is changed
     void destinationCrsChanged();

python/plugins/processing/algs/qgis/FieldsCalculator.py

@@ -100,8 +100,7 @@ def processAlgorithm(self, feedback):
 
         da = QgsDistanceArea()
         da.setSourceCrs(layer.crs())
-        da.setEllipsoidalMode(
-            iface.mapCanvas().mapSettings().hasCrsTransformEnabled())
+        da.setEllipsoidalMode(True)
         da.setEllipsoid(QgsProject.instance().readEntry(
             'Measure', '/Ellipsoid', GEO_NONE)[0])
         exp.setGeomCalculator(da)

python/plugins/processing/algs/qgis/FieldsMapper.py

@@ -104,8 +104,7 @@ def processAlgorithm(self, feedback):
 
         da = QgsDistanceArea()
         da.setSourceCrs(layer.crs())
-        da.setEllipsoidalMode(
-            iface.mapCanvas().mapSettings().hasCrsTransformEnabled())
+        da.setEllipsoidalMode(True)
         da.setEllipsoid(QgsProject.instance().readEntry(
             'Measure', '/Ellipsoid', GEO_NONE)[0])
 

python/plugins/processing/algs/qgis/ServiceAreaFromLayer.py

@@ -209,7 +209,7 @@ def processAlgorithm(self, feedback):
 
         director.addStrategy(strategy)
         builder = QgsGraphBuilder(iface.mapCanvas().mapSettings().destinationCrs(),
-                                  iface.mapCanvas().hasCrsTransformEnabled(),
+                                  True,
                                   tolerance)
 
         feedback.pushInfo(self.tr('Loading start points...'))

python/plugins/processing/algs/qgis/ServiceAreaFromPoint.py

@@ -192,7 +192,7 @@ def processAlgorithm(self, feedback):
 
         director.addStrategy(strategy)
         builder = QgsGraphBuilder(iface.mapCanvas().mapSettings().destinationCrs(),
-                                  iface.mapCanvas().hasCrsTransformEnabled(),
+                                  True,
                                   tolerance)
         feedback.pushInfo(self.tr('Building graph...'))
         snappedPoints = director.makeGraph(builder, [startPoint])

python/plugins/processing/algs/qgis/ShortestPathLayerToPoint.py

@@ -203,7 +203,7 @@ def processAlgorithm(self, feedback):
 
         director.addStrategy(strategy)
         builder = QgsGraphBuilder(iface.mapCanvas().mapSettings().destinationCrs(),
-                                  iface.mapCanvas().hasCrsTransformEnabled(),
+                                  True,
                                   tolerance)
 
         feedback.pushInfo(self.tr('Loading start points...'))

python/plugins/processing/algs/qgis/ShortestPathPointToLayer.py

@@ -203,7 +203,7 @@ def processAlgorithm(self, feedback):
 
         director.addStrategy(strategy)
         builder = QgsGraphBuilder(iface.mapCanvas().mapSettings().destinationCrs(),
-                                  iface.mapCanvas().hasCrsTransformEnabled(),
+                                  True,
                                   tolerance)
 
         feedback.pushInfo(self.tr('Loading end points...'))

python/plugins/processing/algs/qgis/ShortestPathPointToPoint.py

@@ -204,7 +204,7 @@ def processAlgorithm(self, feedback):
 
         director.addStrategy(strategy)
         builder = QgsGraphBuilder(iface.mapCanvas().mapSettings().destinationCrs(),
-                                  iface.mapCanvas().hasCrsTransformEnabled(),
+                                  True,
                                   tolerance)
         feedback.pushInfo(self.tr('Building graph...'))
         snappedPoints = director.makeGraph(builder, [startPoint, endPoint])

src/app/openstreetmap/qgsosmdownloaddialog.cpp

@@ -101,17 +101,14 @@ void QgsOSMDownloadDialog::onExtentCanvas()
 {
   QgsRectangle r( QgisApp::instance()->mapCanvas()->extent() );
 
-  if ( QgisApp::instance()->mapCanvas()->hasCrsTransformEnabled() )
-  {
-    QgsCoordinateReferenceSystem dst = QgsCoordinateReferenceSystem::fromSrsId( GEOCRS_ID );
+  QgsCoordinateReferenceSystem dst = QgsCoordinateReferenceSystem::fromSrsId( GEOCRS_ID );
 
-    QgsCoordinateTransform ct( QgisApp::instance()->mapCanvas()->mapSettings().destinationCrs(), dst );
-    r = ct.transformBoundingBox( r );
-    if ( !r.isFinite() )
-    {
-      QMessageBox::information( this, tr( "OpenStreetMap download" ), tr( "Could not transform canvas extent." ) );
-      return;
-    }
+  QgsCoordinateTransform ct( QgisApp::instance()->mapCanvas()->mapSettings().destinationCrs(), dst );
+  r = ct.transformBoundingBox( r );
+  if ( !r.isFinite() )
+  {
+    QMessageBox::information( this, tr( "OpenStreetMap download" ), tr( "Could not transform canvas extent." ) );
+    return;
   }
 
   setRect( r );

src/app/qgisapp.cpp

@@ -2810,8 +2810,6 @@ void QgisApp::setupConnections()
            this, &QgisApp::mapCanvas_keyPressed );
 
   // connect renderer
-  connect( mMapCanvas, &QgsMapCanvas::hasCrsTransformEnabledChanged,
-           this, &QgisApp::hasCrsTransformEnabled );
   connect( mMapCanvas, &QgsMapCanvas::destinationCrsChanged,
            this, &QgisApp::destinationCrsChanged );
 
@@ -3202,9 +3200,6 @@ void QgisApp::initLayerTreeView()
   connect( QgsProject::instance(), SIGNAL( writeProject( QDomDocument& ) ), mLayerTreeCanvasBridge, SLOT( writeProject( QDomDocument& ) ) );
   connect( QgsProject::instance(), SIGNAL( readProject( QDomDocument ) ), mLayerTreeCanvasBridge, SLOT( readProject( QDomDocument ) ) );
 
-  bool otfTransformAutoEnable = QSettings().value( QStringLiteral( "/Projections/otfTransformAutoEnable" ), true ).toBool();
-  mLayerTreeCanvasBridge->setAutoEnableCrsTransform( otfTransformAutoEnable );
-
   mMapLayerOrder = new QgsCustomLayerOrderWidget( mLayerTreeCanvasBridge, this );
   mMapLayerOrder->setObjectName( QStringLiteral( "theMapLayerOrder" ) );
 
@@ -4607,9 +4602,6 @@ void QgisApp::fileNew( bool promptToSaveFlag, bool forceBlank )
     mMapCanvas->setMapUnits( srs.mapUnits() );
   }
 
-  // enable OTF CRS transformation if necessary
-  mMapCanvas->setCrsTransformEnabled( settings.value( QStringLiteral( "/Projections/otfTransformEnabled" ), 0 ).toBool() );
-
   updateCrsStatusBar();
 
   /** New Empty Project Created
@@ -5357,11 +5349,6 @@ void QgisApp::openProject( QAction *action )
   QString debugme = action->data().toString();
   if ( saveDirty() )
     addProject( debugme );
-
-  //set the projections enabled icon in the status bar
-  int myProjectionEnabledFlag =
-    QgsProject::instance()->readNumEntry( QStringLiteral( "SpatialRefSys" ), QStringLiteral( "/ProjectionsEnabled" ), 0 );
-  mMapCanvas->setCrsTransformEnabled( myProjectionEnabledFlag );
 }
 
 void QgisApp::runScript( const QString &filePath )
@@ -7582,15 +7569,7 @@ void QgisApp::editPaste( QgsMapLayer *destinationLayer )
     return;
 
   pasteVectorLayer->beginEditCommand( tr( "Features pasted" ) );
-  QgsFeatureList features;
-  if ( mMapCanvas->mapSettings().hasCrsTransformEnabled() )
-  {
-    features = clipboard()->transformedCopyOf( pasteVectorLayer->crs(), pasteVectorLayer->fields() );
-  }
-  else
-  {
-    features = clipboard()->copyOf( pasteVectorLayer->fields() );
-  }
+  QgsFeatureList features = clipboard()->transformedCopyOf( pasteVectorLayer->crs(), pasteVectorLayer->fields() );
   int nTotalFeatures = features.count();
 
   QHash<int, int> remap;
@@ -8822,23 +8801,17 @@ void QgisApp::legendLayerZoomNative()
     QgsDebugMsg( "Raster units per pixel  : " + QString::number( layer->rasterUnitsPerPixelX() ) );
     QgsDebugMsg( "MapUnitsPerPixel before : " + QString::number( mMapCanvas->mapUnitsPerPixel() ) );
 
-    if ( mMapCanvas->hasCrsTransformEnabled() )
-    {
-      // get length of central canvas pixel width in source raster crs
-      QgsRectangle e = mMapCanvas->extent();
-      QSize s = mMapCanvas->mapSettings().outputSize();
-      QgsPoint p1( e.center().x(), e.center().y() );
-      QgsPoint p2( e.center().x() + e.width() / s.width(), e.center().y() + e.height() / s.height() );
-      QgsCoordinateTransform ct( mMapCanvas->mapSettings().destinationCrs(), layer->crs() );
-      p1 = ct.transform( p1 );
-      p2 = ct.transform( p2 );
-      double width = sqrt( p1.sqrDist( p2 ) ); // width (actually the diagonal) of reprojected pixel
-      mMapCanvas->zoomByFactor( sqrt( layer->rasterUnitsPerPixelX() * layer->rasterUnitsPerPixelX() + layer->rasterUnitsPerPixelY() * layer->rasterUnitsPerPixelY() ) / width );
-    }
-    else
-    {
-      mMapCanvas->zoomByFactor( qAbs( layer->rasterUnitsPerPixelX() / mMapCanvas->mapUnitsPerPixel() ) );
-    }
+    // get length of central canvas pixel width in source raster crs
+    QgsRectangle e = mMapCanvas->extent();
+    QSize s = mMapCanvas->mapSettings().outputSize();
+    QgsPoint p1( e.center().x(), e.center().y() );
+    QgsPoint p2( e.center().x() + e.width() / s.width(), e.center().y() + e.height() / s.height() );
+    QgsCoordinateTransform ct( mMapCanvas->mapSettings().destinationCrs(), layer->crs() );
+    p1 = ct.transform( p1 );
+    p2 = ct.transform( p2 );
+    double width = sqrt( p1.sqrDist( p2 ) ); // width (actually the diagonal) of reprojected pixel
+    mMapCanvas->zoomByFactor( sqrt( layer->rasterUnitsPerPixelX() * layer->rasterUnitsPerPixelX() + layer->rasterUnitsPerPixelY() * layer->rasterUnitsPerPixelY() ) / width );
+
     mMapCanvas->refresh();
     QgsDebugMsg( "MapUnitsPerPixel after  : " + QString::number( mMapCanvas->mapUnitsPerPixel() ) );
   }
@@ -9189,9 +9162,6 @@ void QgisApp::showOptionsDialog( QWidget *parent, const QString& currentPage )
     qobject_cast<QgsMeasureTool*>( mMapTools.mMeasureArea )->updateSettings();
     qobject_cast<QgsMapToolMeasureAngle*>( mMapTools.mMeasureAngle )->updateSettings();
 
-    bool otfTransformAutoEnable = mySettings.value( QStringLiteral( "/Projections/otfTransformAutoEnable" ), true ).toBool();
-    mLayerTreeCanvasBridge->setAutoEnableCrsTransform( otfTransformAutoEnable );
-
     mMapCanvas->setSegmentationTolerance( mySettings.value( QStringLiteral( "/qgis/segmentationTolerance" ), "0.01745" ).toDouble() );
     mMapCanvas->setSegmentationToleranceType( QgsAbstractGeometry::SegmentationToleranceType( mySettings.value( QStringLiteral( "/qgis/segmentationToleranceType" ), "0" ).toInt() ) );
 
@@ -10311,33 +10281,16 @@ void QgisApp::updateCrsStatusBar()
 {
   mOnTheFlyProjectionStatusButton->setText( mMapCanvas->mapSettings().destinationCrs().authid() );
 
-  if ( mMapCanvas->mapSettings().hasCrsTransformEnabled() )
-  {
-    mOnTheFlyProjectionStatusButton->setToolTip(
-      tr( "Current CRS: %1 (OTF enabled)" ).arg( mMapCanvas->mapSettings().destinationCrs().description() ) );
-    mOnTheFlyProjectionStatusButton->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "mIconProjectionEnabled.svg" ) ) );
-  }
-  else
-  {
-    mOnTheFlyProjectionStatusButton->setText( tr( "%1 (OTF off)" ).arg( mOnTheFlyProjectionStatusButton->text() ) );
-    mOnTheFlyProjectionStatusButton->setToolTip(
-      tr( "Current CRS: %1 (OTF disabled)" ).arg( mMapCanvas->mapSettings().destinationCrs().description() ) );
-    mOnTheFlyProjectionStatusButton->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "mIconProjectionDisabled.svg" ) ) );
-  }
+  mOnTheFlyProjectionStatusButton->setToolTip(
+    tr( "Current CRS: %1" ).arg( mMapCanvas->mapSettings().destinationCrs().description() ) );
+  mOnTheFlyProjectionStatusButton->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "mIconProjectionEnabled.svg" ) ) );
 }
 
 void QgisApp::destinationCrsChanged()
 {
   updateCrsStatusBar();
 }
 
-void QgisApp::hasCrsTransformEnabled( bool flag )
-{
-  // save this information to project
-  QgsProject::instance()->writeEntry( QStringLiteral( "SpatialRefSys" ), QStringLiteral( "/ProjectionsEnabled" ), ( flag ? 1 : 0 ) );
-  updateCrsStatusBar();
-}
-
 // slot to update the progress bar in the status bar
 void QgisApp::showProgress( int progress, int totalSteps )
 {
@@ -11605,16 +11558,11 @@ void QgisApp::readProject( const QDomDocument &doc )
   projectChanged( doc );
 
   // force update of canvas, without automatic changes to extent and OTF projections
-  bool autoEnableCrsTransform = mLayerTreeCanvasBridge->autoEnableCrsTransform();
   bool autoSetupOnFirstLayer = mLayerTreeCanvasBridge->autoSetupOnFirstLayer();
-  mLayerTreeCanvasBridge->setAutoEnableCrsTransform( false );
   mLayerTreeCanvasBridge->setAutoSetupOnFirstLayer( false );
 
   mLayerTreeCanvasBridge->setCanvasLayers();
 
-  if ( autoEnableCrsTransform )
-    mLayerTreeCanvasBridge->setAutoEnableCrsTransform( true );
-
   if ( autoSetupOnFirstLayer )
     mLayerTreeCanvasBridge->setAutoSetupOnFirstLayer( true );
 }

src/app/qgisapp.h

@@ -1194,7 +1194,6 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     void displayMessage( const QString& title, const QString& message, QgsMessageBar::MessageLevel level );
     void removeMapToolMessage();
     void updateMouseCoordinatePrecision();
-    void hasCrsTransformEnabled( bool flag );
     void destinationCrsChanged();
     //    void debugHook();
     //! Add a Layer Definition file

src/app/qgsmaptoollabel.cpp

@@ -105,10 +105,7 @@ void QgsMapToolLabel::createRubberBands()
       if ( mCanvas )
       {
         const QgsMapSettings& s = mCanvas->mapSettings();
-        if ( s.hasCrsTransformEnabled() )
-        {
-          fixPoint = s.mapToLayerCoordinates( vlayer, fixPoint );
-        }
+        fixPoint = s.mapToLayerCoordinates( vlayer, fixPoint );
       }
 
       QgsGeometry pointGeom = QgsGeometry::fromPoint( fixPoint );