Added setThreadSafeRefUnref to LightSource

include/osg/LightSource

@@ -73,6 +73,9 @@ class OSG_EXPORT LightSource : public Group
         /** Set up the local StateSet. */
         void setLocalStateSetModes(StateAttribute::GLModeValue value = StateAttribute::ON);
 
+        /** Set whether to use a mutex to ensure ref() and unref() are thread safe.*/
+        virtual void setThreadSafeRefUnref(bool threadSafe);
+
         virtual BoundingSphere computeBound() const;
 
     protected:

src/osg/LightSource.cpp

@@ -73,3 +73,10 @@ BoundingSphere LightSource::computeBound() const
 
     return bsphere;
 }
+
+void LightSource::setThreadSafeRefUnref(bool threadSafe)
+{
+    Group::setThreadSafeRefUnref(threadSafe);
+
+    if (_light.valid()) _light->setThreadSafeRefUnref(threadSafe);
+}