diff --git a/src/Demos/osgoccluder/osgoccluder.cpp b/src/Demos/osgoccluder/osgoccluder.cpp
index 9840daad7..d80686fa7 100644
--- a/src/Demos/osgoccluder/osgoccluder.cpp
+++ b/src/Demos/osgoccluder/osgoccluder.cpp
@@ -107,6 +107,8 @@ osg::Node* createOccluder(const osg::Vec3& v1,const osg::Vec3& v2,const osg::Vec
     
     geoset->setPrimType(osg::GeoSet::QUADS);
     geoset->setNumPrims(1);
+//     geoset->setPrimType(osg::GeoSet::POINTS);
+//     geoset->setNumPrims(4);
     
     osg::Geode* geode = osgNew osg::Geode;
     geode->addDrawable(geoset);
diff --git a/src/osg/BoundingSphere.cpp b/src/osg/BoundingSphere.cpp
index 8aab06e79..df140908f 100644
--- a/src/osg/BoundingSphere.cpp
+++ b/src/osg/BoundingSphere.cpp
@@ -1,10 +1,11 @@
 #include <osg/BoundingSphere>
+#include <osg/BoundingBox>
 
 using namespace osg;
 
 void BoundingSphere::expandBy(const Vec3& v)
 {
-    if (isValid())
+    if (valid())
     {
         Vec3 dv = v-_center;
         float r = dv.length();
@@ -13,7 +14,7 @@ void BoundingSphere::expandBy(const Vec3& v)
             float dr = (r-_radius)*0.5f;
             _center += dv*(dr/r);
             _radius += dr;
-        }                        // else do nothing as vertex is within sphere.
+        } // else do nothing as vertex is within sphere.
     }
     else
     {
@@ -25,7 +26,7 @@ void BoundingSphere::expandBy(const Vec3& v)
 
 void BoundingSphere::expandRadiusBy(const Vec3& v)
 {
-    if (isValid())
+    if (valid())
     {
         float r = (v-_center).length();
         if (r>_radius) _radius = r;
@@ -41,15 +42,14 @@ void BoundingSphere::expandRadiusBy(const Vec3& v)
 
 void BoundingSphere::expandBy(const BoundingSphere& sh)
 {
-    if (sh.isValid())
+    if (sh.valid())
     {
-        if (isValid())
+        if (valid())
         {
             Vec3 dv = sh._center-_center;
             float dv_len = dv.length();
             if (dv_len+sh._radius>_radius)
             {
-
                 Vec3 e1 = _center-(dv*(_radius/dv_len));
                 Vec3 e2 = sh._center+(dv*(sh._radius/dv_len));
                 _center = (e1+e2)*0.5f;
@@ -68,9 +68,9 @@ void BoundingSphere::expandBy(const BoundingSphere& sh)
 
 void BoundingSphere::expandRadiusBy(const BoundingSphere& sh)
 {
-    if (sh.isValid())
+    if (sh.valid())
     {
-        if (isValid())
+        if (valid())
         {
             float r = (sh._center-_center).length()+sh._radius;
             if (r>_radius) _radius = r;
@@ -83,3 +83,51 @@ void BoundingSphere::expandRadiusBy(const BoundingSphere& sh)
         }
     }
 }
+
+void BoundingSphere::expandBy(const BoundingBox& bb)
+{
+    if (bb.valid())
+    {
+        if (valid())
+        {
+            BoundingBox newbb(bb);
+
+            for(unsigned int c=0;c<8;++c)
+            {
+                Vec3 v = bb.corner(c)-_center; // get the direction vector from corner
+                v.normalize(); // normalise it.
+                v *= -_radius; // move the vector in the opposite direction distance radius.
+                v += _center; // move to absolute position.
+                newbb.expandBy(v); // add it into the new bounding box.
+            }
+            
+            _center = newbb.center();
+            _radius = newbb.radius();
+            
+        }
+        else
+        {
+            _center = bb.center();
+            _radius = bb.radius();
+        }
+    }
+}
+
+void BoundingSphere::expandRadiusBy(const BoundingBox& bb)
+{
+    if (bb.valid())
+    {
+        if (valid())
+        {
+            for(unsigned int c=0;c<8;++c)
+            {
+                expandRadiusBy(bb.corner(c));
+            }
+        }
+        else
+        {
+            _center = bb.center();
+            _radius = bb.radius();
+        }
+    }
+}
diff --git a/src/osg/Geode.cpp b/src/osg/Geode.cpp
index 9b892f771..74492bb21 100644
--- a/src/osg/Geode.cpp
+++ b/src/osg/Geode.cpp
@@ -111,25 +111,9 @@ const bool Geode::computeBound() const
         bb.expandBy((*itr)->getBound());
     }
 
-    if (bb.isValid())
+    if (bb.valid())
     {
-
-        _bsphere._center = bb.center();
-        _bsphere._radius = 0.0f;
-
-        for(itr=_drawables.begin();
-            itr!=_drawables.end();
-            ++itr)
-        {
-            const BoundingBox& bbox = (*itr)->getBound();
-            for(unsigned int c=0;c<8;++c)
-            {
-                _bsphere.expandRadiusBy(bbox.corner(c));
-            }
-        }
-
-//         if (_occluder.valid()) _occluder->computeBound(_bsphere);
-
+        _bsphere.expandBy(bb);
         _bsphere_computed=true;
         return true;
     }
diff --git a/src/osg/OccluderNode.cpp b/src/osg/OccluderNode.cpp
index e3935bf5b..c8d8a17ec 100644
--- a/src/osg/OccluderNode.cpp
+++ b/src/osg/OccluderNode.cpp
@@ -11,3 +11,27 @@ OccluderNode::OccluderNode(const OccluderNode& node,const CopyOp& copyop):
     _occluder(dynamic_cast<ConvexPlanerOccluder*>(copyop(node._occluder.get())))
 {
 }
+
+const bool OccluderNode::computeBound() const
+{
+    bool result = Group::computeBound();
+    
+    if (getOccluder())
+    {
+        BoundingBox bb;
+        const ConvexPlanerPolygon::VertexList& vertexList = getOccluder()->getOccluder().getVertexList();
+        for(ConvexPlanerPolygon::VertexList::const_iterator itr=vertexList.begin();
+            itr!=vertexList.end();
+            ++itr)
+        {
+            bb.expandBy(*itr);
+        }
+        if (bb.valid())
+        {
+            _bsphere.expandBy(bb);
+            _bsphere_computed=true;            
+            result = true;
+        }
+    }
+    return result;
+}