Merge pull request #604 from matthias-kuhn/wmsfix

Fix bad WMS server performance

src/core/qgsmaplayerregistry.cpp

@@ -130,12 +130,16 @@ void QgsMapLayerRegistry::removeMapLayers( QStringList theLayerIds )
   }
 }
 
+void QgsMapLayerRegistry::clearMapLayers()
+{
+  mMapLayers.clear();
+} // QgsMapLayerRegistry::clearMapLayers()
+
 void QgsMapLayerRegistry::removeMapLayer( const QString& theLayerId )
 {
   removeMapLayers( QStringList( theLayerId ) );
 }
 
-
 void QgsMapLayerRegistry::removeAllMapLayers()
 {
   emit removeAll();

src/core/qgsmaplayerregistry.h

@@ -96,6 +96,16 @@ class CORE_EXPORT QgsMapLayerRegistry : public QObject
      */
     QgsMapLayer* addMapLayer( QgsMapLayer * theMapLayer, bool addToLegend = true );
 
+    /**
+     * @brief
+     * Clears the map layer registry silently. No signals are emitted,
+     * no layer is deleted. Whatever this is suitable for... The WMS
+     * server makes use of this.
+     *
+     * Not available in python
+     */
+    void clearMapLayers();
+
     /**
      * @brief
      * Remove a set of layers from the registry

src/mapserver/qgswmsserver.cpp

@@ -373,7 +373,7 @@ QImage* QgsWMSServer::getLegendGraphics()
     currentY += layerSpace;
   }
 
-  QgsMapLayerRegistry::instance()->removeAllMapLayers();
+  QgsMapLayerRegistry::instance()->clearMapLayers();
   delete theImage;
   return paintImage;
 }
@@ -649,7 +649,7 @@ QImage* QgsWMSServer::getMap()
   clearFeatureSelections( selectedLayerIdList );
 
   QgsDebugMsg( "clearing filters" );
-  QgsMapLayerRegistry::instance()->removeAllMapLayers();
+  QgsMapLayerRegistry::instance()->clearMapLayers();
 
 #ifdef QGISDEBUG
   theImage->save( QDir::tempPath() + QDir::separator() + "lastrender.png" );