Refactor LightListCallback to allow for integration in custom Drawables.

components/sceneutil/lightmanager.cpp

@@ -381,21 +381,23 @@ namespace SceneUtil
     {
         osgUtil::CullVisitor* cv = static_cast<osgUtil::CullVisitor*>(nv);
 
+        bool pushedState = pushLightState(node, cv);
+        traverse(node, nv);
+        if (pushedState)
+            cv->popStateSet();
+    }
+
+    bool LightListCallback::pushLightState(osg::Node *node, osgUtil::CullVisitor *cv)
+    {
         if (!mLightManager)
         {
-            mLightManager = findLightManager(nv->getNodePath());
+            mLightManager = findLightManager(cv->getNodePath());
             if (!mLightManager)
-            {
-                traverse(node, nv);
-                return;
-            }
+                return false;
         }
 
         if (!(cv->getCurrentCamera()->getCullMask() & mLightManager->getLightingMask()))
-        {
-            traverse(node, nv);
-            return;
-        }
+            return false;
 
         // Possible optimizations:
         // - cull list of lights by the camera frustum
@@ -404,9 +406,9 @@ namespace SceneUtil
 
         // update light list if necessary
         // makes sure we don't update it more than once per frame when rendering with multiple cameras
-        if (mLastFrameNumber != nv->getTraversalNumber())
+        if (mLastFrameNumber != cv->getTraversalNumber())
         {
-            mLastFrameNumber = nv->getTraversalNumber();
+            mLastFrameNumber = cv->getTraversalNumber();
 
             // Don't use Camera::getViewMatrix, that one might be relative to another camera!
             const osg::RefMatrix* viewMatrix = cv->getCurrentRenderStage()->getInitialViewMatrix();
@@ -469,20 +471,16 @@ namespace SceneUtil
                     while (lightList.size() > maxLights)
                         lightList.pop_back();
                 }
-                stateset = mLightManager->getLightListStateSet(lightList, nv->getTraversalNumber());
+                stateset = mLightManager->getLightListStateSet(lightList, cv->getTraversalNumber());
             }
             else
-                stateset = mLightManager->getLightListStateSet(mLightList, nv->getTraversalNumber());
+                stateset = mLightManager->getLightListStateSet(mLightList, cv->getTraversalNumber());
 
 
             cv->pushStateSet(stateset);
-
-            traverse(node, nv);
-
-            cv->popStateSet();
+            return true;
         }
-        else
-            traverse(node, nv);
+        return false;
     }
 
 }

components/sceneutil/lightmanager.hpp

@@ -9,6 +9,11 @@
 #include <osg/NodeVisitor>
 #include <osg/observer_ptr>
 
+namespace osgUtil
+{
+    class CullVisitor;
+}
+
 namespace SceneUtil
 {
 
@@ -148,6 +153,7 @@ namespace SceneUtil
     /// rendering when the size of a light list exceeds the OpenGL limit on the number of concurrent lights (8). A good
     /// starting point is to attach a LightListCallback to each game object's base node.
     /// @note Not thread safe for CullThreadPerCamera threading mode.
+    /// @note Due to lack of OSG support, the callback does not work on Drawables.
     class LightListCallback : public osg::NodeCallback
     {
     public:
@@ -166,6 +172,8 @@ namespace SceneUtil
 
         void operator()(osg::Node* node, osg::NodeVisitor* nv);
 
+        bool pushLightState(osg::Node* node, osgUtil::CullVisitor* nv);
+
         std::set<SceneUtil::LightSource*>& getIgnoredLightSources() { return mIgnoredLightSources; }
 
     private: