First step of refactoring the osg::Program management in osgTerrain::GeometryPool for better performance by placing default osg::Program and shader defines on a single StateSet below the osgTerrain::Terrain

git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/trunk@14704 16af8721-9629-0410-8352-f15c8da7e697

src/osgTerrain/Terrain.cpp

@@ -123,6 +123,19 @@ void Terrain::traverse(osg::NodeVisitor& nv)
         }
     }
 
+    if (nv.getVisitorType()==osg::NodeVisitor::CULL_VISITOR)
+    {
+        osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(&nv);
+        osg::StateSet* ss = _geometryPool.valid() ? _geometryPool->getRootStateSetForTerrain(this) : 0;
+        if (cv && ss)
+        {
+            cv->pushStateSet(ss);
+            Group::traverse(nv);
+            cv->popStateSet();
+            return;
+        }
+    }
+
     Group::traverse(nv);
 }