Inverted renderer: make sure it works when no painter is here (feature count)

Author: Hugo Mercier

src/core/symbology-ng/qgsinvertedpolygonrenderer.cpp

@@ -73,6 +73,11 @@ void QgsInvertedPolygonRenderer::startRender( QgsRenderContext& context, const Q
   // It must be computed in the destination CRS if reprojection is enabled.
   const QgsMapToPixel& mtp( context.mapToPixel() );
 
+  if ( !context.painter() )
+  {
+    return;
+  }
+
   // convert viewport to dest CRS
   QRect e( context.painter()->viewport() );
   // add some space to hide borders and tend to infinity
@@ -102,7 +107,10 @@ void QgsInvertedPolygonRenderer::startRender( QgsRenderContext& context, const Q
 
 bool QgsInvertedPolygonRenderer::renderFeature( QgsFeature& feature, QgsRenderContext& context, int layer, bool selected, bool drawVertexMarker )
 {
-  Q_UNUSED( context );
+  if ( !context.painter() )
+  {
+    return false;
+  }
 
   // store this feature as a feature to render with decoration if needed
   if ( selected || drawVertexMarker )
@@ -223,6 +231,10 @@ void QgsInvertedPolygonRenderer::stopRender( QgsRenderContext& context )
   if ( !mSubRenderer ) {
     return;
   }
+  if ( !context.painter() )
+  {
+    return;
+  }
 
   for ( FeatureCategoryMap::iterator cit = mFeaturesCategoryMap.begin(); cit != mFeaturesCategoryMap.end(); ++cit)
   {