A little more work on Occlusion culling.

src/osg/CollectOccludersVisitor.cpp

@@ -1,9 +1,16 @@
 #include <osg/CollectOccludersVisitor>
+#include <osg/Transform>
+#include <osg/Switch>
+#include <osg/LOD>
+#include <osg/OccluderNode>
+#include <osg/Projection>
 
 using namespace osg;
 
 CollectOccludersVisitor::CollectOccludersVisitor()
 {
+    // overide the default node visitor mode.
+    setTraversalMode(NodeVisitor::TRAVERSE_ACTIVE_CHILDREN);
 }
 
 CollectOccludersVisitor::~CollectOccludersVisitor()
@@ -15,28 +22,96 @@ void CollectOccludersVisitor::reset()
     CullStack::reset();
 }
 
-void CollectOccludersVisitor::apply(osg::Node&)
+void CollectOccludersVisitor::apply(osg::Node& node)
 {
+    if (isCulled(node)) return;
+
+    // push the culling mode.
+    pushCurrentMask();
+    
+    traverse(node);
+    
+    // pop the culling mode.
+    popCurrentMask();
 }
 
 void CollectOccludersVisitor::apply(osg::Transform& node)
 {
+    if (isCulled(node)) return;
+
+    // push the culling mode.
+    pushCurrentMask();
+
+    ref_ptr<osg::Matrix> matrix = createOrReuseMatrix(getModelViewMatrix());
+    node.getLocalToWorldMatrix(*matrix,this);
+    pushModelViewMatrix(matrix.get());
+    
+    traverse(node);
+
+    popModelViewMatrix();
+
+    // pop the culling mode.
+    popCurrentMask();
 }
 
 void CollectOccludersVisitor::apply(osg::Projection& node)
 {
+    if (isCulled(node)) return;
+
+    // push the culling mode.
+    pushCurrentMask();
+
+    ref_ptr<osg::Matrix> matrix = createOrReuseMatrix(node.getMatrix());
+    pushProjectionMatrix(matrix.get());
+    
+    traverse(node);
+
+    popProjectionMatrix();
+
+    // pop the culling mode.
+    popCurrentMask();
 }
 
 void CollectOccludersVisitor::apply(osg::Switch& node)
 {
+    apply((Group&)node);
 }
 
 void CollectOccludersVisitor::apply(osg::LOD& node)
 {
+    if (isCulled(node)) return;
+
+    int eval = node.evaluate(getEyeLocal(),_LODBias);
+    if (eval<0) return;
+
+    // push the culling mode.
+    pushCurrentMask();
+
+    //notify(INFO) << "selecting child "<<eval<< std::endl;
+    node.getChild(eval)->accept(*this);
+
+    // pop the culling mode.
+    popCurrentMask();
 }
 
 void CollectOccludersVisitor::apply(osg::OccluderNode& node)
 {
+    // need to check if occlusion node is in the occluder
+    // list, if so disable the appropriate ShadowOccluderVolume
+    disableOccluder(_nodePath);
+    
+    std::cout<<"CollectOccludersVisitor:: We have found an Occlusion node in frustum"<<&node<<std::endl;
+
+
+    if (isCulled(node)) return;
+
+    // push the culling mode.
+    pushCurrentMask();
+
+    traverse(node);
+
+    // pop the culling mode.
+    popCurrentMask();
 }
 
 

src/osg/CullStack.cpp

@@ -6,6 +6,7 @@ CullStack::CullStack()
 {
 
     _cullingMode = ENABLE_ALL_CULLING;
+    _LODBias = 1.0f;
     _smallFeatureCullingPixelSize = 3.0f;
 
 }

src/osgUtil/CullVisitor.cpp

@@ -82,8 +82,6 @@ CullVisitor::CullVisitor()
     // overide the default node visitor mode.
     setTraversalMode(NodeVisitor::TRAVERSE_ACTIVE_CHILDREN);
 
-    _LODBias = 1.0f;
-
     //_tsm = LOOK_VECTOR_DISTANCE;
     _tsm = OBJECT_EYE_POINT_DISTANCE;
 
@@ -548,7 +546,7 @@ void CullVisitor::apply(osg::OccluderNode& node)
     // list, if so disable the appropriate ShadowOccluderVolume
     disableOccluder(_nodePath);
     
-    std::cout<<"We are in an Occlusion node"<<&node<<std::endl;
+    std::cout<<"CullVisitor:: We are in an Occlusion node"<<&node<<std::endl;
 
 
     if (isCulled(node)) return;