Minor refactor of label drawing

nyalldawson · nyalldawson · commit 5495f205894e · 2016-10-24T12:02:00.000+10:00
Remove use of scale factors from PAL layer settings and use
render context factors directly
diff --git a/python/core/qgspallabeling.sip b/python/core/qgspallabeling.sip
@@ -515,10 +515,6 @@ class QgsPalLayerSettings
     //! Z-Index of label, where labels with a higher z-index are rendered on top of labels with a lower z-index
     double zIndex;
 
-    //-- scale factors
-    double vectorScaleFactor; //scale factor painter units->pixels
-    double rasterCompressFactor; //pixel resolution scale factor
-
     // called from register feature hook
     void calculateLabelSize( const QFontMetricsF* fm, QString text, double& labelX, double& labelY, QgsFeature* f = 0, QgsRenderContext* context = 0 );
 
@@ -836,15 +832,15 @@ class QgsPalLabeling : QgsLabelingEngineInterface
 
     static void drawLabelBuffer( QgsRenderContext& context,
                                  const QgsLabelComponent &component,
-                                 const QgsPalLayerSettings& tmpLyr );
+                                 const QgsTextFormat& format );
 
     static void drawLabelBackground( QgsRenderContext& context,
                                      QgsLabelComponent component,
-                                     const QgsPalLayerSettings& tmpLyr );
+                                     const QgsTextFormat& format );
 
     static void drawLabelShadow( QgsRenderContext &context,
                                  const QgsLabelComponent &component,
-                                 const QgsPalLayerSettings& tmpLyr );
+                                 const QgsTextFormat& format );
 
     //! load/save engine settings to project file
     void loadEngineSettings();
diff --git a/src/app/qgslabelpreview.cpp b/src/app/qgslabelpreview.cpp
@@ -75,9 +75,7 @@ void QgsLabelPreview::paintEvent( QPaintEvent *e )
     mContext.setPainter( &p );
     QgsLabelComponent component;
     component.setText( text() );
-    QgsPalLayerSettings tmpLyr;
-    tmpLyr.setFormat( mFormat );
-    QgsPalLabeling::drawLabelBuffer( mContext, component, tmpLyr );
+    QgsPalLabeling::drawLabelBuffer( mContext, component, mFormat );
   }
 
   QPainterPath path;
diff --git a/src/core/qgspallabeling.cpp b/src/core/qgspallabeling.cpp
@@ -175,10 +175,6 @@ QgsPalLayerSettings::QgsPalLayerSettings()
   obstacleType = PolygonInterior;
   zIndex = 0.0;
 
-  // scale factors
-  vectorScaleFactor = 1.0;
-  rasterCompressFactor = 1.0;
-
   // data defined string and old-style index values
   // NOTE: in QPair use -1 for second value (other values are for old-style layer properties migration)
 
@@ -390,9 +386,6 @@ QgsPalLayerSettings& QgsPalLayerSettings::operator=( const QgsPalLayerSettings &
   }
   mDataDefinedNames = s.mDataDefinedNames;
 
-  // scale factors
-  vectorScaleFactor = s.vectorScaleFactor;
-  rasterCompressFactor = s.rasterCompressFactor;
   return *this;
 }
 
@@ -1431,7 +1424,7 @@ void QgsPalLayerSettings::calculateLabelSize( const QFontMetricsF* fm, QString t
   double labelHeight = fm->ascent() + fm->descent(); // ignore +1 for baseline
 
   h += fm->height() + static_cast< double >(( lines - 1 ) * labelHeight * multilineH );
-  h /= rasterCompressFactor;
+  h /= context->rasterScaleFactor();
 
   for ( int i = 0; i < lines; ++i )
   {
@@ -1441,7 +1434,7 @@ void QgsPalLayerSettings::calculateLabelSize( const QFontMetricsF* fm, QString t
       w = width;
     }
   }
-  w /= rasterCompressFactor;
+  w /= context->rasterScaleFactor();
 
 #if 0 // XXX strk
   QgsPoint ptSize = xform->toMapCoordinatesF( w, h );
@@ -2252,7 +2245,7 @@ void QgsPalLayerSettings::registerFeature( QgsFeature& f, QgsRenderContext &cont
   double topMargin = qMax( 0.25 * labelFontMetrics->ascent(), 0.0 );
   double bottomMargin = 1.0 + labelFontMetrics->descent();
   QgsLabelFeature::VisualMargin vm( topMargin, 0.0, bottomMargin, 0.0 );
-  vm *= xform->mapUnitsPerPixel() / rasterCompressFactor;
+  vm *= xform->mapUnitsPerPixel() / context.rasterScaleFactor();
   ( *labelFeature )->setVisualMargin( vm );
 
   // store the label's calculated font for later use during painting
@@ -2262,7 +2255,7 @@ void QgsPalLayerSettings::registerFeature( QgsFeature& f, QgsRenderContext &cont
   // TODO: only for placement which needs character info
   // account for any data defined font metrics adjustments
   lf->calculateInfo( placement == QgsPalLayerSettings::Curved || placement == QgsPalLayerSettings::PerimeterCurved,
-                     labelFontMetrics.data(), xform, rasterCompressFactor, maxcharanglein, maxcharangleout );
+                     labelFontMetrics.data(), xform, context.rasterScaleFactor(), maxcharanglein, maxcharangleout );
   // for labelFeature the LabelInfo is passed to feat when it is registered
 
   // TODO: allow layer-wide feature dist in PAL...?
@@ -2297,7 +2290,7 @@ void QgsPalLayerSettings::registerFeature( QgsFeature& f, QgsRenderContext &cont
   }
   else //mm
   {
-    distance *= vectorScaleFactor;
+    distance *= context.scaleFactor();
   }
 
   // when using certain placement modes, we force a tiny minimum distance. This ensures that
@@ -4082,11 +4075,10 @@ void QgsPalLabeling::drawLabelCandidateRect( pal::LabelPosition* lp, QPainter* p
 
 void QgsPalLabeling::drawLabelBuffer( QgsRenderContext& context,
                                       const QgsLabelComponent& component,
-                                      const QgsPalLayerSettings& tmpLyr )
+                                      const QgsTextFormat& format )
 {
   QPainter* p = context.painter();
 
-  QgsTextFormat format = tmpLyr.format();
   QgsTextBufferSettings buffer = format.buffer();
 
   double penSize = QgsTextRenderer::scaleToPixelContext( buffer.size(), context,
@@ -4120,7 +4112,7 @@ void QgsPalLabeling::drawLabelBuffer( QgsRenderContext& context,
     bufferComponent.setOrigin( QgsPoint( 0.0, 0.0 ) );
     bufferComponent.setPicture( &buffPict );
     bufferComponent.setPictureBuffer( penSize / 2.0 );
-    drawLabelShadow( context, bufferComponent, tmpLyr );
+    drawLabelShadow( context, bufferComponent, format );
   }
 
   p->save();
@@ -4141,9 +4133,8 @@ void QgsPalLabeling::drawLabelBuffer( QgsRenderContext& context,
 
 void QgsPalLabeling::drawLabelBackground( QgsRenderContext& context,
     QgsLabelComponent component,
-    const QgsPalLayerSettings& tmpLyr )
+    const QgsTextFormat& format )
 {
-  QgsTextFormat format = tmpLyr.format();
   QgsTextBackgroundSettings background = format.background();
 
   QPainter* p = context.painter();
@@ -4274,7 +4265,7 @@ void QgsPalLabeling::drawLabelBackground( QgsRenderContext& context,
       p->rotate( component.rotationOffset() );
       p->translate( -svgSize / 2, svgSize / 2 );
 
-      drawLabelShadow( context, component, tmpLyr );
+      drawLabelShadow( context, component, format );
       p->restore();
 
       delete svgShdwM;
@@ -4415,7 +4406,7 @@ void QgsPalLabeling::drawLabelBackground( QgsRenderContext& context,
 
       component.setSize( QgsPoint( rect.width(), rect.height() ) );
       component.setOffset( QgsPoint( rect.width() / 2, -rect.height() / 2 ) );
-      drawLabelShadow( context, component, tmpLyr );
+      drawLabelShadow( context, component, format );
     }
 
     p->setOpacity( background.opacity() );
@@ -4434,15 +4425,14 @@ void QgsPalLabeling::drawLabelBackground( QgsRenderContext& context,
 
 void QgsPalLabeling::drawLabelShadow( QgsRenderContext& context,
                                       const QgsLabelComponent& component,
-                                      const QgsPalLayerSettings& tmpLyr )
+                                      const QgsTextFormat& format )
 {
+  QgsTextShadowSettings shadow = format.shadow();
+
   // incoming component sizes should be multiplied by rasterCompressFactor, as
   // this allows shadows to be created at paint device dpi (e.g. high resolution),
   // then scale device painter by 1.0 / rasterCompressFactor for output
 
-  QgsTextFormat format = tmpLyr.format();
-  QgsTextShadowSettings shadow = format.shadow();
-
   QPainter* p = context.painter();
   double componentWidth = component.size().x(), componentHeight = component.size().y();
   double xOffset = component.offset().x(), yOffset = component.offset().y();
@@ -4451,7 +4441,7 @@ void QgsPalLabeling::drawLabelShadow( QgsRenderContext& context,
   // generate pixmap representation of label component drawing
   bool mapUnits = shadow.blurRadiusUnit() == QgsUnitTypes::RenderMapUnits;
   double radius = QgsTextRenderer::scaleToPixelContext( shadow.blurRadius(), context, shadow.blurRadiusUnit(), !mapUnits, shadow.blurRadiusMapUnitScale() );
-  radius /= ( mapUnits ? tmpLyr.vectorScaleFactor / component.dpiRatio() : 1 );
+  radius /= ( mapUnits ? context.scaleFactor() / component.dpiRatio() : 1 );
   radius = static_cast< int >( radius + 0.5 );
 
   // TODO: add labeling gui option to adjust blurBufferClippingScale to minimize pixels, or
diff --git a/src/core/qgspallabeling.h b/src/core/qgspallabeling.h
@@ -535,10 +535,6 @@ class CORE_EXPORT QgsPalLayerSettings
     //! Z-Index of label, where labels with a higher z-index are rendered on top of labels with a lower z-index
     double zIndex;
 
-    //-- scale factors
-    double vectorScaleFactor; //scale factor painter units->pixels
-    double rasterCompressFactor; //pixel resolution scale factor
-
     // called from register feature hook
     void calculateLabelSize( const QFontMetricsF* fm, QString text, double& labelX, double& labelY, QgsFeature* f = nullptr, QgsRenderContext* context = nullptr );
 
@@ -961,15 +957,15 @@ class CORE_EXPORT QgsPalLabeling : public QgsLabelingEngineInterface
 
     static void drawLabelBuffer( QgsRenderContext& context,
                                  const QgsLabelComponent &component,
-                                 const QgsPalLayerSettings& tmpLyr );
+                                 const QgsTextFormat& format );
 
     static void drawLabelBackground( QgsRenderContext& context,
                                      QgsLabelComponent component,
-                                     const QgsPalLayerSettings& tmpLyr );
+                                     const QgsTextFormat& format );
 
     static void drawLabelShadow( QgsRenderContext &context,
                                  const QgsLabelComponent &component,
-                                 const QgsPalLayerSettings& tmpLyr );
+                                 const QgsTextFormat& format );
 
     //! load/save engine settings to project file
     void loadEngineSettings();
diff --git a/src/core/qgsvectorlayerlabelprovider.cpp b/src/core/qgsvectorlayerlabelprovider.cpp
@@ -213,10 +213,6 @@ bool QgsVectorLayerLabelProvider::prepare( const QgsRenderContext& context, QSet
   // TODO: ideally these (non-configuration) members should get out of QgsPalLayerSettings to here
   // (together with registerFeature() & related methods) and QgsPalLayerSettings just stores config
 
-  //raster and vector scale factors
-  lyr.vectorScaleFactor = context.scaleFactor();
-  lyr.rasterCompressFactor = context.rasterScaleFactor();
-
   // save the pal layer to our layer context (with some additional info)
   lyr.fieldIndex = mFields.lookupField( lyr.fieldName );
 
@@ -575,7 +571,7 @@ void QgsVectorLayerLabelProvider::drawLabelPrivate( pal::LabelPosition* label, Q
     component.setCenter( centerPt );
     component.setSize( QgsPoint( label->getWidth(), label->getHeight() ) );
 
-    QgsPalLabeling::drawLabelBackground( context, component, tmpLyr );
+    QgsPalLabeling::drawLabelBackground( context, component, tmpLyr.format() );
   }
 
   else if ( drawType == QgsPalLabeling::LabelBuffer
@@ -689,7 +685,7 @@ void QgsVectorLayerLabelProvider::drawLabelPrivate( pal::LabelPosition* label, Q
 
       // scale down painter: the font size has been multiplied by raster scale factor
       // to workaround a Qt font scaling bug with small font sizes
-      painter->scale( 1.0 / tmpLyr.rasterCompressFactor, 1.0 / tmpLyr.rasterCompressFactor );
+      painter->scale( 1.0 / context.rasterScaleFactor(), 1.0 / context.rasterScaleFactor() );
 
       // figure x offset for horizontal alignment of multiple lines
       double xMultiLineOffset = 0.0;
@@ -717,7 +713,7 @@ void QgsVectorLayerLabelProvider::drawLabelPrivate( pal::LabelPosition* label, Q
       if ( drawType == QgsPalLabeling::LabelBuffer )
       {
         // draw label's buffer
-        QgsPalLabeling::drawLabelBuffer( context, component, tmpLyr );
+        QgsPalLabeling::drawLabelBuffer( context, component, tmpLyr.format() );
       }
       else
       {
@@ -746,7 +742,7 @@ void QgsVectorLayerLabelProvider::drawLabelPrivate( pal::LabelPosition* label, Q
           component.setPictureBuffer( 0.0 ); // no pen width to deal with
           component.setOrigin( QgsPoint( 0.0, 0.0 ) );
 
-          QgsPalLabeling::drawLabelShadow( context, component, tmpLyr );
+          QgsPalLabeling::drawLabelShadow( context, component, tmpLyr.format() );
         }
 
         // paint the text
