Added stats handler to track performance effects of new GLBeginEndAdapter usage

examples/osgparticle/osgparticle.cpp

@@ -17,6 +17,7 @@
 */
 
 #include <osgViewer/Viewer>
+#include <osgViewer/ViewerEventHandlers>
 
 #include <osg/Group>
 #include <osg/Geode>
@@ -368,6 +369,9 @@ int main(int, char **)
     osg::Group *root = new osg::Group;
     build_world(root);
    
+    // add the stats handler
+    viewer.addEventHandler(new osgViewer::StatsHandler);
+
     // add a viewport to the viewer and attach the scene graph.
     viewer.setSceneData(root);