Fix relationship between scale<->extent in the save [canvas] as image/pdf dialog

Author: nirvn

src/app/qgsmapsavedialog.cpp

@@ -82,9 +82,9 @@ QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, co
   }
   mDrawDecorations->setText( tr( "Draw active decorations: %1" ).arg( !activeDecorations.isEmpty() ? activeDecorations : tr( "none" ) ) );
 
-  connect( mResolutionSpinBox, static_cast < void ( QSpinBox::* )( int ) > ( &QSpinBox::valueChanged ), this, &QgsMapSaveDialog::updateDpi );
-  connect( mOutputWidthSpinBox, static_cast < void ( QSpinBox::* )( int ) > ( &QSpinBox::valueChanged ), this, &QgsMapSaveDialog::updateOutputWidth );
-  connect( mOutputHeightSpinBox, static_cast < void ( QSpinBox::* )( int ) > ( &QSpinBox::valueChanged ), this, &QgsMapSaveDialog::updateOutputHeight );
+  connect( mResolutionSpinBox, &QSpinBox::editingFinished, this, [ = ] { updateDpi( mResolutionSpinBox->value() ); } );
+  connect( mOutputWidthSpinBox, &QSpinBox::editingFinished, this, [ = ] { updateOutputWidth( mOutputWidthSpinBox->value() );} );
+  connect( mOutputHeightSpinBox, &QSpinBox::editingFinished, this, [ = ] { updateOutputWidth( mOutputHeightSpinBox->value() );} );
   connect( mExtentGroupBox, &QgsExtentGroupBox::extentChanged, this, &QgsMapSaveDialog::updateExtent );
   connect( mScaleWidget, &QgsScaleWidget::scaleChanged, this, &QgsMapSaveDialog::updateScale );
   connect( mLockAspectRatio, &QgsRatioLockButton::lockChanged, this, &QgsMapSaveDialog::lockChanged );
@@ -230,7 +230,7 @@ void QgsMapSaveDialog::updateScale( double scale )
   calculator.setMapUnits( mExtentGroupBox->currentCrs().mapUnits() );
   calculator.setDpi( mDpi );
 
-  double oldScale = 1 / ( calculator.calculate( mExtent, mSize.width() ) );
+  double oldScale = calculator.calculate( mExtent, mSize.width() );
   double scaleRatio = scale / oldScale;
   mExtent.scale( scaleRatio );
   mExtentGroupBox->setOutputExtentFromUser( mExtent, mExtentGroupBox->currentCrs() );
@@ -299,6 +299,7 @@ void QgsMapSaveDialog::applyMapSettings( QgsMapSettings &mapSettings )
   mapSettings.setOutputDpi( dpi() );
   mapSettings.setBackgroundColor( mMapCanvas->canvasColor() );
   mapSettings.setRotation( mMapCanvas->rotation() );
+  mapSettings.setEllipsoid( QgsProject::instance()->ellipsoid() );
   mapSettings.setLayers( mMapCanvas->layers() );
   mapSettings.setLabelingEngineSettings( mMapCanvas->mapSettings().labelingEngineSettings() );
   mapSettings.setTransformContext( QgsProject::instance()->transformContext() );