And the same for graduated symbol renderer in svn head

git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@6507 c8812cc2-4d05-0410-92ff-de0c093fc19c

src/core/renderer/qgsgraduatedsymbolrenderer.cpp

@@ -86,11 +86,68 @@ void QgsGraduatedSymbolRenderer::removeSymbols()
     mSymbols.clear();
 }
 
+bool QgsGraduatedSymbolRenderer::willRenderFeature(QgsFeature *f)
+{
+  return (symbolForFeature(f) != 0);
+}
+
 void QgsGraduatedSymbolRenderer::renderFeature(QPainter * p, QgsFeature & f, QImage* img, 
 	double* scalefactor, bool selected, double widthScale)
+{
+  QgsSymbol* theSymbol = symbolForFeature(&f);
+  if(!theSymbol)
+    {
+      if ( img && mVectorType == QGis::Point )
+	{
+	  img->fill(0);
+	}
+      else if ( mVectorType != QGis::Point )
+	{
+	  p->setPen(Qt::NoPen);
+	  p->setBrush(Qt::NoBrush);
+	}
+      return;
+    }
+
+  //set the qpen and qpainter to the right values
+  // Point 
+  if ( img && mVectorType == QGis::Point ) 
+    {
+      *img = theSymbol->getPointSymbolAsImage(  widthScale, selected, mSelectionColor );
+      if ( scalefactor ) 
+	{
+	  *scalefactor = 1;
+	}
+    } 
+
+  // Line, polygon
+  if ( mVectorType != QGis::Point )
+    {
+      if( !selected ) 
+	{
+	  QPen pen=theSymbol->pen();
+	  pen.setWidthF ( widthScale * pen.width() );
+	  p->setPen(pen);
+	  p->setBrush(theSymbol->brush());
+	}
+      else
+	{
+	  QPen pen=theSymbol->pen();
+	  pen.setColor(mSelectionColor);
+	  pen.setWidthF ( widthScale * pen.width() );
+	  QBrush brush=theSymbol->brush();
+	  brush.setColor(mSelectionColor);
+	  p->setPen(pen);
+	  p->setBrush(brush);
+	}
+    }
+}
+
+
+QgsSymbol* QgsGraduatedSymbolRenderer::symbolForFeature(const QgsFeature* f)
 {
   //first find out the value for the classification attribute
-  const QgsAttributeMap& attrs = f.attributeMap();
+  const QgsAttributeMap& attrs = f->attributeMap();
   double value = attrs[mClassificationField].fieldValue().toDouble();
 
   std::list < QgsSymbol* >::iterator it;
@@ -104,46 +161,10 @@ void QgsGraduatedSymbolRenderer::renderFeature(QPainter * p, QgsFeature & f, QIm
   }
 
   if (it == mSymbols.end())      //only draw features which are covered by a render item
-  {
-    QgsDebugMsg("Warning, value is contained in no class");
-    p->setPen(QPen(Qt::NoPen));
-    p->setBrush(QBrush(Qt::NoBrush));
-    return;
-  } 
-  else
-  {
-    //set the qpen and qpainter to the right values
-    // Point 
-    if ( img && mVectorType == QGis::Point ) 
     {
-      *img = (*it)->getPointSymbolAsImage(  widthScale,
-          selected, mSelectionColor );
-
-      if ( scalefactor ) *scalefactor = 1;
-    } 
-
-    // Line, polygon
-    if ( mVectorType != QGis::Point )
-    {
-      if( !selected ) 
-      {
-        QPen pen=(*it)->pen();
-        pen.setWidthF ( widthScale * pen.width() );
-        p->setPen(pen);
-        p->setBrush((*it)->brush());
-      }
-      else
-      {
-        QPen pen=(*it)->pen();
-        pen.setColor(mSelectionColor);
-        pen.setWidthF ( widthScale * pen.width() );
-        QBrush brush=(*it)->brush();
-        brush.setColor(mSelectionColor);
-        p->setPen(pen);
-        p->setBrush(brush);
-      }
+      return 0;
     }
-  }
+  return (*it);
 }
 
 void QgsGraduatedSymbolRenderer::readXML(const QDomNode& rnode, QgsVectorLayer& vl)

src/core/renderer/qgsgraduatedsymbolrenderer.h

@@ -40,6 +40,9 @@ class CORE_EXPORT QgsGraduatedSymbolRenderer: public QgsRenderer
     int classificationField() const;
     /**Removes all symbols*/
     void removeSymbols();
+    /** Determines if a feature will be rendered or not 
+	@param f a pointer to the feature to determine if rendering will happen*/
+    bool willRenderFeature(QgsFeature *f);
     /**Renders an OGRFeature
      \param p a painter (usually the one from the current map canvas)
      \param f a pointer to a feature to render
@@ -70,6 +73,7 @@ class CORE_EXPORT QgsGraduatedSymbolRenderer: public QgsRenderer
     int mClassificationField;
     /**List holding the symbols for the individual classes*/
     std::list<QgsSymbol*> mSymbols;
+    QgsSymbol* symbolForFeature(const QgsFeature* f);
 
 };