Disable blend modes when printing or pdf exporting as vector, prevents missing composer items in output

nyalldawson · nyalldawson · commit 2caf0e0cbc6b · 2013-05-10T15:21:57.000+10:00
diff --git a/src/app/composer/qgscomposer.cpp b/src/app/composer/qgscomposer.cpp
@@ -637,6 +637,18 @@ void QgsComposer::on_mActionExportAsPDF_triggered()
     showBlendModePrintingWarning();
   }
 
+  // If we are not printing as raster, temporarily disable advanced effects
+  // as QPrinter does not support composition modes and can result
+  // in items missing from the output
+  if ( mComposition->printAsRaster() )
+  {
+    mComposition->setUseAdvancedEffects( true );
+  }
+  else
+  {
+    mComposition->setUseAdvancedEffects( false );
+  }
+
   bool hasAnAtlas = mComposition->atlasComposition().enabled();
   bool atlasOnASingleFile = hasAnAtlas && mComposition->atlasComposition().singleFile();
   QgsAtlasComposition* atlasMap = &mComposition->atlasComposition();
@@ -795,6 +807,11 @@ void QgsComposer::on_mActionExportAsPDF_triggered()
     mComposition->exportAsPDF( outputFileName );
   }
 
+  if ( ! mComposition->useAdvancedEffects() )
+  {
+    //Switch advanced effects back on
+    mComposition->setUseAdvancedEffects( true );
+  }
   mView->setPaintingEnabled( true );
   QApplication::restoreOverrideCursor();
 }
@@ -816,6 +833,18 @@ void QgsComposer::on_mActionPrint_triggered()
     showBlendModePrintingWarning();
   }
 
+  // If we are not printing as raster, temporarily disable advanced effects
+  // as QPrinter does not support composition modes and can result
+  // in items missing from the output
+  if ( mComposition->printAsRaster() )
+  {
+    mComposition->setUseAdvancedEffects( true );
+  }
+  else
+  {
+    mComposition->setUseAdvancedEffects( false );
+  }
+
   //orientation and page size are already set to QPrinter in the page setup dialog
   QPrintDialog printDialog( &mPrinter, 0 );
   if ( printDialog.exec() != QDialog::Accepted )
@@ -887,6 +916,11 @@ void QgsComposer::on_mActionPrint_triggered()
     painter.end();
   }
 
+  if ( ! mComposition->useAdvancedEffects() )
+  {
+    //Switch advanced effects back on
+    mComposition->setUseAdvancedEffects( true );
+  }
   mView->setPaintingEnabled( true );
   QApplication::restoreOverrideCursor();
 }
diff --git a/src/core/composer/qgscomposeritem.cpp b/src/core/composer/qgscomposeritem.cpp
@@ -56,6 +56,7 @@ QgsComposerItem::QgsComposerItem( QgsComposition* composition, bool manageZValue
     , mLastValidViewScaleFactor( -1 )
     , mRotation( 0 )
     , mBlendMode( QPainter::CompositionMode_SourceOver )
+    , mEffectsEnabled( true )
     , mTransparency( 0 )
     , mLastUsedPositionMode( UpperLeft )
     , mId( "" )
@@ -78,6 +79,7 @@ QgsComposerItem::QgsComposerItem( qreal x, qreal y, qreal width, qreal height, Q
     , mLastValidViewScaleFactor( -1 )
     , mRotation( 0 )
     , mBlendMode( QPainter::CompositionMode_SourceOver )
+    , mEffectsEnabled( true )
     , mTransparency( 0 )
     , mLastUsedPositionMode( UpperLeft )
     , mId( "" )
@@ -107,7 +109,6 @@ void QgsComposerItem::init( bool manageZValue )
   // Setup composer effect
   mEffect = new QgsComposerEffect();
   setGraphicsEffect( mEffect );
-
 }
 
 QgsComposerItem::~QgsComposerItem()
@@ -906,6 +907,13 @@ void QgsComposerItem::setTransparency( int transparency )
   setOpacity( 1. - ( transparency / 100. ) );
 }
 
+void QgsComposerItem::setEffectsEnabled( bool effectsEnabled )
+{
+  //enable or disable the QgsComposerEffect applied to this item
+  mEffectsEnabled = effectsEnabled;
+  mEffect->setEnabled( effectsEnabled );
+}
+
 void QgsComposerItem::hoverMoveEvent( QGraphicsSceneHoverEvent * event )
 {
   if ( isSelected() )
diff --git a/src/core/composer/qgscomposeritem.h b/src/core/composer/qgscomposeritem.h
@@ -221,6 +221,15 @@ class CORE_EXPORT QgsComposerItem: public QObject, public QGraphicsRectItem
     /** Sets the item's transparency */
     void setTransparency( int transparency );
 
+    /** Returns true if effects (eg blend modes) are enabled for the item
+     * @note introduced in 2.0
+    */
+    bool effectsEnabled() const {return mEffectsEnabled;}
+    /** Sets whether effects (eg blend modes) are enabled for the item
+     * @note introduced in 2.0
+    */
+    void setEffectsEnabled( bool effectsEnabled );
+
     /**Composite operations for item groups do nothing per default*/
     virtual void addItem( QgsComposerItem* item ) { Q_UNUSED( item ); }
     virtual void removeItems() {}
@@ -337,7 +346,7 @@ class CORE_EXPORT QgsComposerItem: public QObject, public QGraphicsRectItem
 
     /**Composition blend mode for item*/
     QPainter::CompositionMode mBlendMode;
-
+    bool mEffectsEnabled;
     QgsComposerEffect *mEffect;
 
     /**Item transparency*/
diff --git a/src/core/composer/qgscomposermap.cpp b/src/core/composer/qgscomposermap.cpp
@@ -168,6 +168,9 @@ void QgsComposerMap::draw( QPainter *painter, const QgsRectangle& extent, const
   // force vector output (no caching of marker images etc.)
   theRendererContext->setForceVectorOutput( true );
 
+  // make the renderer respect the composition's useAdvancedEffects flag
+  theRendererContext->setUseAdvancedEffects( mComposition->useAdvancedEffects() );
+
   //force composer map scale for scale dependent visibility
   double bk_scale = theMapRenderer.scale();
   theMapRenderer.setScale( scale() );
diff --git a/src/core/composer/qgscomposition.cpp b/src/core/composer/qgscomposition.cpp
@@ -47,10 +47,25 @@
 #include <QDir>
 
 
-QgsComposition::QgsComposition( QgsMapRenderer* mapRenderer ) :
-    QGraphicsScene( 0 ), mMapRenderer( mapRenderer ), mPlotStyle( QgsComposition::Preview ), mPageWidth( 297 ), mPageHeight( 210 ), mSpaceBetweenPages( 10 ), mPrintAsRaster( false ), mSelectionTolerance( 0.0 ),
-    mSnapToGrid( false ), mSnapGridResolution( 10.0 ), mSnapGridOffsetX( 0.0 ), mSnapGridOffsetY( 0.0 ), mAlignmentSnap( true ), mAlignmentSnapTolerance( 2 ),
-    mActiveItemCommand( 0 ), mActiveMultiFrameCommand( 0 ), mAtlasComposition( this )
+QgsComposition::QgsComposition( QgsMapRenderer* mapRenderer )
+    : QGraphicsScene( 0 ),
+    mMapRenderer( mapRenderer ),
+    mPlotStyle( QgsComposition::Preview ),
+    mPageWidth( 297 ),
+    mPageHeight( 210 ),
+    mSpaceBetweenPages( 10 ),
+    mPrintAsRaster( false ),
+    mUseAdvancedEffects( true ),
+    mSelectionTolerance( 0.0 ),
+    mSnapToGrid( false ),
+    mSnapGridResolution( 10.0 ),
+    mSnapGridOffsetX( 0.0 ),
+    mSnapGridOffsetY( 0.0 ),
+    mAlignmentSnap( true ),
+    mAlignmentSnapTolerance( 2 ),
+    mActiveItemCommand( 0 ),
+    mActiveMultiFrameCommand( 0 ),
+    mAtlasComposition( this )
 {
   setBackgroundBrush( Qt::gray );
   addPaperItem();
@@ -59,10 +74,25 @@ QgsComposition::QgsComposition( QgsMapRenderer* mapRenderer ) :
   loadSettings();
 }
 
-QgsComposition::QgsComposition():
-    QGraphicsScene( 0 ), mMapRenderer( 0 ), mPlotStyle( QgsComposition::Preview ),  mPageWidth( 297 ), mPageHeight( 210 ), mSpaceBetweenPages( 10 ), mPrintAsRaster( false ),
-    mSelectionTolerance( 0.0 ), mSnapToGrid( false ), mSnapGridResolution( 10.0 ), mSnapGridOffsetX( 0.0 ), mSnapGridOffsetY( 0.0 ), mAlignmentSnap( true ),
-    mAlignmentSnapTolerance( 2 ), mActiveItemCommand( 0 ), mActiveMultiFrameCommand( 0 ), mAtlasComposition( this )
+QgsComposition::QgsComposition()
+    : QGraphicsScene( 0 ),
+    mMapRenderer( 0 ),
+    mPlotStyle( QgsComposition::Preview ),
+    mPageWidth( 297 ),
+    mPageHeight( 210 ),
+    mSpaceBetweenPages( 10 ),
+    mPrintAsRaster( false ),
+    mUseAdvancedEffects( true ),
+    mSelectionTolerance( 0.0 ),
+    mSnapToGrid( false ),
+    mSnapGridResolution( 10.0 ),
+    mSnapGridOffsetX( 0.0 ),
+    mSnapGridOffsetY( 0.0 ),
+    mAlignmentSnap( true ),
+    mAlignmentSnapTolerance( 2 ),
+    mActiveItemCommand( 0 ),
+    mActiveMultiFrameCommand( 0 ),
+    mAtlasComposition( this )
 {
   loadSettings();
 
@@ -318,6 +348,24 @@ const QgsComposerItem* QgsComposition::getComposerItemByUuid( QString theUuid )
   return 0;
 }
 
+
+void QgsComposition::setUseAdvancedEffects( bool effectsEnabled )
+{
+  mUseAdvancedEffects = effectsEnabled;
+
+  //toggle effects for all composer items
+  QList<QGraphicsItem*> itemList = items();
+  QList<QGraphicsItem*>::const_iterator itemIt = itemList.constBegin();
+  for ( ; itemIt != itemList.constEnd(); ++itemIt )
+  {
+    QgsComposerItem* composerItem = dynamic_cast<QgsComposerItem*>( *itemIt );
+    if ( composerItem )
+    {
+      composerItem->setEffectsEnabled( effectsEnabled );
+    }
+  }
+}
+
 int QgsComposition::pixelFontSize( double pointSize ) const
 {
   //in QgsComposition, one unit = one mm
diff --git a/src/core/composer/qgscomposition.h b/src/core/composer/qgscomposition.h
@@ -182,6 +182,13 @@ class CORE_EXPORT QgsComposition: public QGraphicsScene
     bool printAsRaster() const {return mPrintAsRaster;}
     void setPrintAsRaster( bool enabled ) { mPrintAsRaster = enabled; }
 
+    /**Returns true if a composition should use advanced effects such as blend modes
+      @note added in 1.9*/
+    bool useAdvancedEffects() const {return mUseAdvancedEffects;}
+    /**Used to enable or disable advanced effects such as blend modes in a composition
+      @note: added in version 1.9*/
+    void setUseAdvancedEffects( bool effectsEnabled );
+
     double selectionTolerance() const { return mSelectionTolerance; }
     void setSelectionTolerance( double tol );
 
@@ -375,6 +382,9 @@ class CORE_EXPORT QgsComposition: public QGraphicsScene
     /**Flag if map should be printed as a raster (via QImage). False by default*/
     bool mPrintAsRaster;
 
+    /**Flag if advanced visual effects such as blend modes should be used. True by default*/
+    bool mUseAdvancedEffects;
+
     /**Distance tolerance for item selection (in mm)*/
     double mSelectionTolerance;
 
diff --git a/src/core/qgsmaprenderer.cpp b/src/core/qgsmaprenderer.cpp
@@ -397,9 +397,12 @@ void QgsMapRenderer::render( QPainter* painter, double* forceWidthScale )
                  .arg( ml->blendMode() )
                );
 
-    // Set the QPainter composition mode so that this layer is rendered using
-    // the desired blending mode
-    mypContextPainter->setCompositionMode( ml->blendMode() );
+    if ( mRenderContext.useAdvancedEffects() )
+    {
+      // Set the QPainter composition mode so that this layer is rendered using
+      // the desired blending mode
+      mypContextPainter->setCompositionMode( ml->blendMode() );
+    }
 
     if ( !ml->hasScaleBasedVisibility() || ( ml->minimumScale() <= mScale && mScale < ml->maximumScale() ) || mOverview )
     {
@@ -515,7 +518,7 @@ void QgsMapRenderer::render( QPainter* painter, double* forceWidthScale )
       // before compositing this on the map. This effectively flattens the layer and prevents
       // blending occuring between objects on the layer
       // (this is not required for raster layers or when layer caching is enabled, since that has the same effect)
-      if (( ml->blendMode()  != QPainter::CompositionMode_SourceOver ) &&
+      if (( mRenderContext.useAdvancedEffects() ) && ( ml->blendMode()  != QPainter::CompositionMode_SourceOver ) &&
           ( ml->type() != QgsMapLayer::RasterLayer ) &&
           ( split || !mySettings.value( "/qgis/enable_render_caching", false ).toBool() ) )
       {
@@ -581,7 +584,7 @@ void QgsMapRenderer::render( QPainter* painter, double* forceWidthScale )
       }
 
       // If we flattened this layer for alternate blend modes, composite it now
-      if (( ml->blendMode()  != QPainter::CompositionMode_SourceOver ) &&
+      if (( mRenderContext.useAdvancedEffects() ) && ( ml->blendMode()  != QPainter::CompositionMode_SourceOver ) &&
           ( ml->type() != QgsMapLayer::RasterLayer ) &&
           ( split || !mySettings.value( "/qgis/enable_render_caching", false ).toBool() ) )
       {
diff --git a/src/core/qgspallabeling.cpp b/src/core/qgspallabeling.cpp
@@ -2286,7 +2286,10 @@ void QgsPalLabeling::drawLabel( pal::LabelPosition* label, QgsRenderContext& con
         }
 
         // paint the text
-        painter->setCompositionMode( tmpLyr.blendMode );
+        if ( context.useAdvancedEffects() )
+        {
+          painter->setCompositionMode( tmpLyr.blendMode );
+        }
 //        painter->setPen( Qt::NoPen );
 //        painter->setBrush( tmpLyr.textColor );
 //        painter->drawPath( path );
@@ -2350,7 +2353,10 @@ void QgsPalLabeling::drawLabelBuffer( QgsRenderContext& context,
   }
 
   p->save();
-  p->setCompositionMode( tmpLyr.bufferBlendMode );
+  if ( context.useAdvancedEffects() )
+  {
+    p->setCompositionMode( tmpLyr.bufferBlendMode );
+  }
 //  p->setPen( pen );
 //  p->setBrush( tmpColor );
 //  p->drawPath( path );
@@ -2512,7 +2518,10 @@ void QgsPalLabeling::drawLabelBackground( QgsRenderContext& context,
                                          ( 100.0 - ( double )( tmpLyr.shapeTransparency ) ) / 100.0 );
 
     p->save();
-    p->setCompositionMode( tmpLyr.shapeBlendMode );
+    if ( context.useAdvancedEffects() )
+    {
+      p->setCompositionMode( tmpLyr.shapeBlendMode );
+    }
     p->translate( component.center().x(), component.center().y() );
     p->rotate( component.rotation() );
     double xoff = tmpLyr.scaleToPixelContext( tmpLyr.shapeOffset.x(), context, tmpLyr.shapeOffsetUnits );
@@ -2642,7 +2651,10 @@ void QgsPalLabeling::drawLabelBackground( QgsRenderContext& context,
     }
 
     p->setOpacity(( 100.0 - ( double )( tmpLyr.shapeTransparency ) ) / 100.0 );
-    p->setCompositionMode( tmpLyr.shapeBlendMode );
+    if ( context.useAdvancedEffects() )
+    {
+      p->setCompositionMode( tmpLyr.shapeBlendMode );
+    }
 
     // scale for any print output or image saving @ specific dpi
     p->scale( component.dpiRatio(), component.dpiRatio() );
@@ -2744,7 +2756,10 @@ void QgsPalLabeling::drawLabelShadow( QgsRenderContext& context,
 
   p->save();
   p->setRenderHints( QPainter::Antialiasing | QPainter::SmoothPixmapTransform );
-  p->setCompositionMode( tmpLyr.shadowBlendMode );
+  if ( context.useAdvancedEffects() )
+  {
+    p->setCompositionMode( tmpLyr.shadowBlendMode );
+  }
   p->setOpacity(( 100.0 - ( double )( tmpLyr.shadowTransparency ) ) / 100.0 );
 
   double scale = ( double )tmpLyr.shadowScale / 100.0;
diff --git a/src/core/qgsrendercontext.cpp b/src/core/qgsrendercontext.cpp
@@ -23,6 +23,7 @@ QgsRenderContext::QgsRenderContext()
     mCoordTransform( 0 ),
     mDrawEditingInformation( true ),
     mForceVectorOutput( false ),
+    mUseAdvancedEffects( true ),
     mRenderingStopped( false ),
     mScaleFactor( 1.0 ),
     mRasterScaleFactor( 1.0 ),
diff --git a/src/core/qgsrendercontext.h b/src/core/qgsrendercontext.h
@@ -59,6 +59,13 @@ class CORE_EXPORT QgsRenderContext
 
     bool forceVectorOutput() const {return mForceVectorOutput;}
 
+    /**Returns true if advanced effects such as blend modes such be used
+      @note added in 1.9*/
+    bool useAdvancedEffects() const {return mUseAdvancedEffects;}
+    /**Used to enable or disable advanced effects such as blend modes
+      @note: added in version 1.9*/
+    void setUseAdvancedEffects( bool enabled ) { mUseAdvancedEffects = enabled; }
+
     bool drawEditingInformation() const {return mDrawEditingInformation;}
 
     double rendererScale() const {return mRendererScale;}
@@ -104,6 +111,9 @@ class CORE_EXPORT QgsRenderContext
     /**If true then no rendered vector elements should be cached as image*/
     bool mForceVectorOutput;
 
+    /**Flag if advanced visual effects such as blend modes should be used. True by default*/
+    bool mUseAdvancedEffects;
+
     QgsMapToPixel mMapToPixel;
 
     /**True if the rendering has been canceled*/
