Refined the CollectOccluderVisitor so that it checks the subgraph below

a node contains occluders before traversing.

include/osg/CollectOccludersVisitor

@@ -50,6 +50,25 @@ class SG_EXPORT CollectOccludersVisitor : public osg::NodeVisitor, public osg::C
         bool                        _createDrawables;
         ShadowVolumeOccluderList    _collectedOccluderList;
 
+        inline void handle_callbacks_and_traverse(osg::Node& node)
+        {
+            osg::NodeCallback* callback = node.getAppCallback();
+            if (callback) (*callback)(&node,this);
+            else if (node.getNumChildrenRequiringAppTraversal()>0) traverse(node);
+        }
+        inline void handle_cull_callbacks_and_traverse(osg::Node& node)
+        {
+            /*osg::NodeCallback* callback = node.getCullCallback();
+            if (callback) (*callback)(&node,this);
+            else*/ if (node.getNumChildrenWithOccluderNodes()>0) traverse(node);
+        }
+
+        inline void handle_cull_callbacks_and_accept(osg::Node& node,osg::Node* acceptNode)
+        {
+            /*osg::NodeCallback* callback = node.getCullCallback();
+            if (callback) (*callback)(&node,this);
+            else*/ if (node.getNumChildrenWithOccluderNodes()>0) acceptNode->accept(*this);
+        }
 };
 
 }

src/osg/CollectOccludersVisitor.cpp

@@ -32,7 +32,7 @@ void CollectOccludersVisitor::apply(osg::Node& node)
     // push the culling mode.
     pushCurrentMask();
     
-    traverse(node);
+    handle_cull_callbacks_and_traverse(node);
     
     // pop the culling mode.
     popCurrentMask();
@@ -49,7 +49,7 @@ void CollectOccludersVisitor::apply(osg::Transform& node)
     node.getLocalToWorldMatrix(*matrix,this);
     pushModelViewMatrix(matrix.get());
     
-    traverse(node);
+    handle_cull_callbacks_and_traverse(node);
 
     popModelViewMatrix();
 
@@ -67,7 +67,7 @@ void CollectOccludersVisitor::apply(osg::Projection& node)
     ref_ptr<osg::Matrix> matrix = createOrReuseMatrix(node.getMatrix());
     pushProjectionMatrix(matrix.get());
     
-    traverse(node);
+    handle_cull_callbacks_and_traverse(node);
 
     popProjectionMatrix();
 
@@ -91,7 +91,7 @@ void CollectOccludersVisitor::apply(osg::LOD& node)
     pushCurrentMask();
 
     //notify(INFO) << "selecting child "<<eval<< std::endl;
-    node.getChild(eval)->accept(*this);
+    handle_cull_callbacks_and_accept(node,node.getChild(eval));
 
     // pop the culling mode.
     popCurrentMask();
@@ -130,7 +130,7 @@ void CollectOccludersVisitor::apply(osg::OccluderNode& node)
         }
     }
 
-    traverse(node);
+    handle_cull_callbacks_and_traverse(node);
 
     // pop the culling mode.
     popCurrentMask();

src/osg/ShadowVolumeOccluder.cpp

@@ -189,7 +189,6 @@ Drawable* createOccluderDrawable(const PointList& front, const PointList& back)
 }
 
 
-
 bool ShadowVolumeOccluder::computeOccluder(const NodePath& nodePath,const ConvexPlanerOccluder& occluder,CullStack& cullStack,bool createDrawables)
 {
 
@@ -276,6 +275,62 @@ bool ShadowVolumeOccluder::computeOccluder(const NodePath& nodePath,const Convex
         }
         
         
+        for(ConvexPlanerOccluder::HoleList::const_iterator hitr=occluder.getHoleList().begin();
+            hitr!=occluder.getHoleList().end();
+            ++hitr)
+        {
+            PointList points;
+            if (clip(cullingset.getFrustum().getPlaneList(),hitr->getVertexList(),points)>=3)
+            {
+                _holeList.push_back();
+                Polytope& polytope = _holeList.back();
+
+                // compute the points on the far plane.
+                PointList farPoints;
+                farPoints.reserve(points.size());
+                transform(points,farPoints,MVP);
+                pushToFarPlane(farPoints);
+                transform(farPoints,invP);
+
+                // move the occlude points into projection space.
+                transform(points,MV);
+
+                // create the front face of the occluder
+                Plane occludePlane = computeFrontPlane(points);
+
+                // create the sides of the occluder
+                computePlanes(points,farPoints,polytope.getPlaneList());
+
+                polytope.setupMask();
+
+                // if the front face is pointing away from the eye point flip the whole polytope.
+                if (occludePlane[3]>0.0f)
+                {
+                    polytope.flip();
+                }
+
+                if (createDrawables && !nodePath.empty())
+                {
+                    osg::Group* group = dynamic_cast<osg::Group*>(nodePath.back());
+                    if (group)
+                    {
+
+                        osg::Matrix invMV;
+                        invMV.invert(MV);
+
+                        transform(points,invMV);
+                        transform(farPoints,invMV);
+
+                        osg::Geode* geode = osgNew osg::Geode;
+                        group->addChild(geode);
+                        geode->addDrawable(createOccluderDrawable(points,farPoints));
+                    }
+                }
+            }
+            
+        }
+
+
         return true;
     }
     else