Speed up ControllerVisitor by skipping sub graphs that have no ChildrenRequiringUpdateTraversal()

apps/openmw/mwrender/npcanimation.cpp

@@ -770,12 +770,14 @@ bool NpcAnimation::addOrReplaceIndividualPart(ESM::PartReferenceType type, int g
         }
     }
 
+    osg::Node* node = mObjectParts[type]->getNode();
+    if (node->getNumChildrenRequiringUpdateTraversal() > 0)
+    {
         boost::shared_ptr<SceneUtil::ControllerSource> src;
         if (type == ESM::PRT_Head)
         {
             src = mHeadAnimationTime;
 
-        osg::Node* node = mObjectParts[type]->getNode();
             if (node->getUserDataContainer())
             {
                 for (unsigned int i=0; i<node->getUserDataContainer()->getNumUserObjects(); ++i)
@@ -806,7 +808,8 @@ bool NpcAnimation::addOrReplaceIndividualPart(ESM::PartReferenceType type, int g
             src.reset(new NullAnimationTime);
 
         SceneUtil::AssignControllerSourcesVisitor assignVisitor(src);
-    mObjectParts[type]->getNode()->accept(assignVisitor);
+        node->accept(assignVisitor);
+    }
 
     return true;
 }

components/sceneutil/controller.cpp

@@ -81,6 +81,7 @@ namespace SceneUtil
             callback = callback->getNestedCallback();
         }
 
+        if (node.getNumChildrenRequiringUpdateTraversal() > 0)
             traverse(node);
     }