Make @cluster_size, @cluster_color usable in displacement renderer too

Author: nyalldawson

src/core/symbology-ng/qgspointclusterrenderer.cpp

@@ -55,40 +55,6 @@ void QgsPointClusterRenderer::drawGroup( QPointF centerPoint, QgsRenderContext&
 {
   if ( group.size() > 1 )
   {
-    //scan through symbols to check color, eg if all clustered symbols are same color
-    QColor groupColor;
-    ClusteredGroup::const_iterator groupIt = group.constBegin();
-    for ( ; groupIt != group.constEnd(); ++groupIt )
-    {
-      if ( !groupIt->symbol )
-        continue;
-
-      if ( !groupColor.isValid() )
-      {
-        groupColor = groupIt->symbol->color();
-      }
-      else
-      {
-        if ( groupColor != groupIt->symbol->color() )
-        {
-          groupColor = QColor();
-          break;
-        }
-      }
-    }
-
-    if ( groupColor.isValid() )
-    {
-      context.expressionContext().lastScope()->setVariable( "cluster_color", QgsSymbolLayerUtils::encodeColor( groupColor ) );
-    }
-    else
-    {
-      //mixed colors
-      context.expressionContext().lastScope()->setVariable( "cluster_color", "" );
-    }
-
-    //multiple clustered symbols, so draw just the cluster symbol
-    context.expressionContext().lastScope()->setVariable( "cluster_size", group.size() );
     mClusterSymbol->renderPoint( centerPoint, &( group.at( 0 ).feature ), context, -1, false );
   }
   else

src/core/symbology-ng/qgspointdisplacementrenderer.cpp

@@ -64,6 +64,7 @@ QgsPointDisplacementRenderer* QgsPointDisplacementRenderer::clone() const
 
 void QgsPointDisplacementRenderer::drawGroup( QPointF centerPoint, QgsRenderContext& context, const ClusteredGroup& group )
 {
+
   //calculate max diagonal size from all symbols in group
   double diagonal = 0;
 
@@ -88,9 +89,9 @@ void QgsPointDisplacementRenderer::drawGroup( QPointF centerPoint, QgsRenderCont
   if ( circleRadius > 0 )
     drawCircle( circleRadius, symbolContext, centerPoint, group.size() );
 
-  //draw mid point
   if ( group.size() > 1 )
   {
+    //draw mid point
     QgsFeature firstFeature = group.at( 0 ).feature;
     if ( mCenterSymbol )
     {

src/core/symbology-ng/qgspointdistancerenderer.cpp

@@ -140,7 +140,9 @@ void QgsPointDistanceRenderer::drawGroup( const ClusteredGroup& group, QgsRender
   QgsGeometry centroid = groupGeom.centroid();
   QPointF pt = _getPoint( context, *static_cast<QgsPointV2*>( centroid.geometry() ) );
 
+  context.expressionContext().appendScope( createGroupScope( group ) );
   drawGroup( pt, context, group );
+  delete context.expressionContext().popScope();
 }
 
 void QgsPointDistanceRenderer::setEmbeddedRenderer( QgsFeatureRenderer* r )
@@ -407,6 +409,48 @@ void QgsPointDistanceRenderer::drawLabels( QPointF centerPoint, QgsSymbolRenderC
   }
 }
 
+QgsExpressionContextScope* QgsPointDistanceRenderer::createGroupScope( const ClusteredGroup& group ) const
+{
+  QgsExpressionContextScope* clusterScope = new QgsExpressionContextScope();
+  if ( group.size() > 1 )
+  {
+    //scan through symbols to check color, eg if all clustered symbols are same color
+    QColor groupColor;
+    ClusteredGroup::const_iterator groupIt = group.constBegin();
+    for ( ; groupIt != group.constEnd(); ++groupIt )
+    {
+      if ( !groupIt->symbol )
+        continue;
+
+      if ( !groupColor.isValid() )
+      {
+        groupColor = groupIt->symbol->color();
+      }
+      else
+      {
+        if ( groupColor != groupIt->symbol->color() )
+        {
+          groupColor = QColor();
+          break;
+        }
+      }
+    }
+
+    if ( groupColor.isValid() )
+    {
+      clusterScope->setVariable( "cluster_color", QgsSymbolLayerUtils::encodeColor( groupColor ) );
+    }
+    else
+    {
+      //mixed colors
+      clusterScope->setVariable( "cluster_color", "" );
+    }
+
+    clusterScope->setVariable( "cluster_size", group.size() );
+  }
+  return clusterScope;
+}
+
 QgsMarkerSymbol* QgsPointDistanceRenderer::firstSymbolForFeature( QgsFeature& feature, QgsRenderContext &context )
 {
   if ( !mRenderer )

src/core/symbology-ng/qgspointdistancerenderer.h

@@ -276,6 +276,12 @@ class CORE_EXPORT QgsPointDistanceRenderer: public QgsFeatureRenderer
     */
     QgsMarkerSymbol* firstSymbolForFeature( QgsFeature& feature, QgsRenderContext& context );
 
+    /** Creates an expression context scope for a clustered group, with variables reflecting the group's properties.
+     * @param group clustered group
+     * @returns new expression context scope
+     */
+    QgsExpressionContextScope* createGroupScope( const ClusteredGroup& group ) const;
+
 };
 
 #endif // QGSPOINTDISTANCERENDERER_H

tests/src/python/test_qgspointclusterrenderer.py

@@ -40,7 +40,8 @@
                        QgsMarkerSymbol,
                        QgsSingleSymbolRenderer,
                        QgsPointDisplacementRenderer,
-                       QgsMapSettings
+                       QgsMapSettings,
+                       QgsDataDefined
                        )
 from qgis.testing import start_app, unittest
 from utilities import (unitTestDataPath)
@@ -162,6 +163,24 @@ def testRenderWithin(self):
         renderchecker.setControlName('expected_cluster_cluster')
         self.assertTrue(renderchecker.runTest('expected_cluster_cluster'))
 
+    def testRenderVariables(self):
+        """ test rendering with expression variables in marker """
+        self.layer.renderer().setTolerance(10)
+
+        old_marker = self.layer.renderer().clusterSymbol().clone()
+
+        new_marker = QgsMarkerSymbol.createSimple({'color': '#ffff00', 'size': '3', 'outline_style': 'no'})
+        new_marker.symbolLayer(0).setDataDefinedProperty('color', QgsDataDefined('@cluster_color'))
+        new_marker.symbolLayer(0).setDataDefinedProperty('size', QgsDataDefined('@cluster_size*2'))
+        self.layer.renderer().setClusterSymbol(new_marker)
+        renderchecker = QgsMultiRenderChecker()
+        renderchecker.setMapSettings(self.mapsettings)
+        renderchecker.setControlPathPrefix('cluster_renderer')
+        renderchecker.setControlName('expected_cluster_variables')
+        result = renderchecker.runTest('expected_cluster_variables')
+        self.layer.renderer().setClusterSymbol(old_marker)
+        self.assertTrue(result)
+
 
 if __name__ == '__main__':
     unittest.main()

tests/src/python/test_qgspointdisplacementrenderer.py

@@ -42,7 +42,8 @@
                        QgsMarkerSymbol,
                        QgsSingleSymbolRenderer,
                        QgsPointClusterRenderer,
-                       QgsMapSettings
+                       QgsMapSettings,
+                       QgsDataDefined
                        )
 from qgis.testing import start_app, unittest
 from utilities import (unitTestDataPath)
@@ -185,6 +186,23 @@ def testRenderWithin(self):
         renderchecker.setControlName('expected_displacement_cluster')
         self.assertTrue(renderchecker.runTest('expected_displacement_cluster'))
 
+    def testRenderVariables(self):
+        """ test rendering with expression variables in marker """
+        self.layer.renderer().setTolerance(10)
+
+        old_marker = self.layer.renderer().centerSymbol().clone()
+
+        new_marker = QgsMarkerSymbol.createSimple({'color': '#ffff00', 'size': '3', 'outline_style': 'no'})
+        new_marker.symbolLayer(0).setDataDefinedProperty('color', QgsDataDefined('@cluster_color'))
+        new_marker.symbolLayer(0).setDataDefinedProperty('size', QgsDataDefined('@cluster_size*2'))
+        self.layer.renderer().setCenterSymbol(new_marker)
+        renderchecker = QgsMultiRenderChecker()
+        renderchecker.setMapSettings(self.mapsettings)
+        renderchecker.setControlPathPrefix('displacement_renderer')
+        renderchecker.setControlName('expected_displacement_variables')
+        result = renderchecker.runTest('expected_displacement_variables')
+        self.layer.renderer().setCenterSymbol(old_marker)
+        self.assertTrue(result)
 
 if __name__ == '__main__':
     unittest.main()