Remove some more QgsComposition::mapSettings use

Author: nyalldawson

python/core/composer/qgscomposerutils.sip

@@ -249,5 +249,5 @@ class QgsComposerUtils
      * QgsComposition::referenceMap().
      * @note added in QGIS 3.0
      */
-    static QgsRenderContext createRenderContext( QgsComposition* composition, QPainter& painter );
+    static QgsRenderContext createRenderContext( QgsComposition* composition, QPainter* painter );
 };

src/core/composer/qgscomposerarrow.cpp

@@ -182,7 +182,7 @@ void QgsComposerArrow::drawLine( QPainter *painter )
   painter->scale( 1 / dotsPerMM, 1 / dotsPerMM ); //scale painter from mm to dots
 
   //setup render context
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *painter );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, painter );
   context.setForceVectorOutput( true );
 
   QgsExpressionContext expressionContext = createExpressionContext();

src/core/composer/qgscomposerlegend.cpp

@@ -111,10 +111,10 @@ void QgsComposerLegend::paint( QPainter* painter, const QStyleOptionGraphicsItem
     mSettings.setMmPerMapUnit( mComposerMap->mapUnitsToMM() );
 
     // use a temporary QgsMapSettings to find out real map scale
-    QgsMapSettings ms = mComposerMap->composition()->mapSettings();
-    ms.setOutputSize( QSizeF( mComposerMap->rect().width() * dotsPerMM, mComposerMap->rect().height() * dotsPerMM ).toSize() );
-    ms.setExtent( *mComposerMap->currentMapExtent() );
-    ms.setOutputDpi( dpi );
+    QSizeF mapSizePixels = QSizeF( mComposerMap->rect().width() * dotsPerMM, mComposerMap->rect().height() * dotsPerMM );
+    QgsRectangle mapExtent = *mComposerMap->currentMapExtent();
+
+    QgsMapSettings ms = mComposerMap->mapSettings( mapExtent, mapSizePixels, dpi );
     mSettings.setMapScale( ms.scale() );
   }
   mInitialMapScaleCalculated = true;

src/core/composer/qgscomposermapgrid.cpp

@@ -636,7 +636,7 @@ void QgsComposerMapGrid::draw( QPainter* p )
   p->scale( 1 / dotsPerMM, 1 / dotsPerMM ); //scale painter from mm to dots
 
   //setup render context
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *p );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, p );
   context.setForceVectorOutput( true );
   QgsExpressionContext expressionContext = createExpressionContext();
   context.setExpressionContext( expressionContext );
@@ -2056,8 +2056,7 @@ void QgsComposerMapGrid::calculateMaxExtension( double& top, double& right, doub
   }
 
   //setup render context
-  QgsMapSettings ms = mComposerMap->composition()->mapSettings();
-  QgsRenderContext context = QgsRenderContext::fromMapSettings( ms );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, nullptr );
   QgsExpressionContext expressionContext = createExpressionContext();
   context.setExpressionContext( expressionContext );
 

src/core/composer/qgscomposermapoverview.cpp

@@ -92,7 +92,7 @@ void QgsComposerMapOverview::draw( QPainter *painter )
   double dotsPerMM = painter->device()->logicalDpiX() / 25.4;
 
   //setup render context
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *painter );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, painter );
   context.setForceVectorOutput( true );
   QgsExpressionContext expressionContext = createExpressionContext();
   context.setExpressionContext( expressionContext );

src/core/composer/qgscomposernodesitem.cpp

@@ -137,7 +137,7 @@ void QgsComposerNodesItem::drawNodes( QPainter *painter ) const
   symbol.data()->setSize( rectSize );
   symbol.data()->setAngle( 45 );
 
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *painter );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, painter );
   context.setForceVectorOutput( true );
 
   QgsExpressionContext expressionContext = createExpressionContext();
@@ -168,7 +168,7 @@ void QgsComposerNodesItem::drawSelectedNode( QPainter *painter ) const
   symbol.reset( QgsMarkerSymbol::createSimple( properties ) );
   symbol.data()->setSize( rectSize );
 
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *painter );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, painter );
   context.setForceVectorOutput( true );
 
   QgsExpressionContext expressionContext = createExpressionContext();

src/core/composer/qgscomposerpolygon.cpp

@@ -73,7 +73,7 @@ void QgsComposerPolygon::_draw( QPainter *painter )
   //setup painter scaling to dots so that raster symbology is drawn to scale
   const double dotsPerMM = painter->device()->logicalDpiX() / 25.4;
 
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *painter );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, painter );
   context.setForceVectorOutput( true );
   context.setExpressionContext( createExpressionContext() );
 

src/core/composer/qgscomposerpolyline.cpp

@@ -100,7 +100,7 @@ void QgsComposerPolyline::_draw( QPainter *painter )
 {
   double dotsPerMM = painter->device()->logicalDpiX() / 25.4;
 
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *painter );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, painter );
   context.setForceVectorOutput( true );
 
   QgsExpressionContext expressionContext = createExpressionContext();

src/core/composer/qgscomposershape.cpp

@@ -179,7 +179,7 @@ void QgsComposerShape::drawShapeUsingSymbol( QPainter* p )
   double dotsPerMM = p->device()->logicalDpiX() / 25.4;
 
   //setup render context
-  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, *p );
+  QgsRenderContext context = QgsComposerUtils::createRenderContext( mComposition, p );
   context.setForceVectorOutput( true );
   QgsExpressionContext expressionContext = createExpressionContext();
   context.setExpressionContext( expressionContext );

src/core/composer/qgscomposerutils.cpp

@@ -548,15 +548,16 @@ void QgsComposerUtils::drawText( QPainter *painter, const QRectF &rect, const QS
   painter->restore();
 }
 
-QgsRenderContext QgsComposerUtils::createRenderContext( QgsComposition* composition, QPainter &painter )
+QgsRenderContext QgsComposerUtils::createRenderContext( QgsComposition* composition, QPainter* painter )
 {
   QgsComposerMap* referenceMap = composition ? composition->referenceMap() : nullptr;
   if ( !referenceMap )
   {
-    return QgsRenderContext::fromQPainter( &painter );
+    return QgsRenderContext::fromQPainter( painter );
   }
 
-  int dpi = painter.device()->logicalDpiX();
+  // default to 88 dpi if no painter specified
+  int dpi = ( painter && painter->device() ) ? painter->device()->logicalDpiX() : 88;
   double dotsPerMM = dpi / 25.4;
 
   // get map settings from reference map
@@ -565,6 +566,7 @@ QgsRenderContext QgsComposerUtils::createRenderContext( QgsComposition* composit
   QgsMapSettings ms = referenceMap->mapSettings( extent, mapSizeMM * dotsPerMM, dpi );
 
   QgsRenderContext context = QgsRenderContext::fromMapSettings( ms );
-  context.setPainter( &painter );
+  if ( painter )
+    context.setPainter( painter );
   return context;
 }