Always use topological editing if using avoid intersection (where pos…

…sible also to background layers). Without topological editing, it is possible to have very small gaps between the polygons
qgis · Feb 18, 2013 · dc074b3 · dc074b3
1 parent ee96d38
commit dc074b3
Showing 1 changed file with 20 additions and 1 deletion.
diff --git a/src/app/qgsmaptooladdfeature.cpp b/src/app/qgsmaptooladdfeature.cpp
@@ -273,7 +273,26 @@ void QgsMapToolAddFeature::canvasReleaseEvent( QMouseEvent * e )
       {
         //add points to other features to keep topology up-to-date
         int topologicalEditing = QgsProject::instance()->readNumEntry( "Digitizing", "/TopologicalEditing", 0 );
-        if ( topologicalEditing )
+
+        //use always topological editing for avoidIntersection.
+        //Otherwise, no way to guarantee the geometries don't have a small gap in between.
+        QStringList intersectionLayers = QgsProject::instance()->readListEntry( "Digitizing", "/AvoidIntersectionsList" );
+        bool avoidIntersection = !intersectionLayers.isEmpty();
+        if ( avoidIntersection ) //try to add topological points also to background layers
+        {
+          QStringList::const_iterator lIt = intersectionLayers.constBegin();
+          for ( ; lIt != intersectionLayers.constEnd(); ++lIt )
+          {
+            QgsMapLayer* ml = QgsMapLayerRegistry::instance()->mapLayer( *lIt );
+            QgsVectorLayer* vl = qobject_cast<QgsVectorLayer*>( ml );
+            //can only add topological points if background layer is editable...
+            if ( vl && vl->geometryType() == QGis::Polygon && vl->isEditable() )
+            {
+              vl->addTopologicalPoints( f->geometry() );
+            }
+          }
+        }
+        else if ( topologicalEditing )
         {
           vlayer->addTopologicalPoints( f->geometry() );
         }