From Morten Hauknes, "I have been using the getLastVisiblePixelCount on pre 3.0 osg. I believe maybe this was a private function that we made public in our side. I use(d) this method to make a simple algorithm to tell how much visible an object was in percent.

So with the 3.0 api change we propose the following change:
- put OSG_EXPORT on the QueryGeometry class so that we get access to the getNumPixels method.
- Create a function called getQueryGeometry that returns a casted _queryGeode->getDrawable(). Or a function called getQueryGeode that returns _queryGeode."

include/osg/OcclusionQueryNode

@@ -60,7 +60,7 @@ public:
 
 // QueryGeometry -- A Drawable that performs an occlusion query,
 //   using its geometric data as the query geometry.
-class QueryGeometry : public osg::Geometry
+class OSG_EXPORT QueryGeometry : public osg::Geometry
 {
 public:
     QueryGeometry( const std::string& oqnName=std::string("") );
@@ -141,6 +141,10 @@ public:
     osg::StateSet* getQueryStateSet();
     const osg::StateSet* getQueryStateSet() const;
 
+    // Get the QueryGeometry object used for occlusion query. Returns 0 if no QueryGeometry is created.
+    osg::QueryGeometry* getQueryGeometry();
+    const osg::QueryGeometry* getQueryGeometry() const;
+
     // Set and get the StateSet used by the OcclusionQueryNode
     //   when rendering the debug query geometry (see setDebugDisplay).
     void setDebugStateSet( osg::StateSet* ss );

src/osg/OcclusionQueryNode.cpp

@@ -754,5 +754,25 @@ void OcclusionQueryNode::discardDeletedQueryObjects( unsigned int contextID )
     QueryGeometry::discardDeletedQueryObjects( contextID );
 }
 
+osg::QueryGeometry* OcclusionQueryNode::getQueryGeometry()
+{
+    if (_queryGeode && _queryGeode->getDrawable( 0 ))
+    {
+        QueryGeometry* qg = static_cast< QueryGeometry* >( _queryGeode->getDrawable( 0 ) );
+        return qg;
+    }
+    return 0;
+}
+
+const osg::QueryGeometry* OcclusionQueryNode::getQueryGeometry() const
+{
+    if (_queryGeode && _queryGeode->getDrawable( 0 ))
+    {
+        QueryGeometry* qg = static_cast< QueryGeometry* >( _queryGeode->getDrawable( 0 ) );
+        return qg;
+    }
+    return 0;
+}
+
 
 }