From Pjotr Svetachov, "small bug which I have found in the
FlattenStaticTransformsDuplicatingSharedSubgraphsVisitor: the visitor
will replace part of the tree when visiting the nodes but it does not
update the current node path to reflect this. If you then have
multiple nested transform nodes it will usually crash and sometimes it
won't crash but the resulting mesh will miss some nodes."
From Pjotr Svetachov, "when you restart threading
with startThreading/stopThreading the _drawQueue and _availableQueue
are not reset properly. This can lead to a deadlock when threading is
started again. So before threading is started again the queues must be
reset. This deadlock is also reported earlier by someone else in here:
http://forum.openscenegraph.org/viewtopic.php?p=43415#43415"