Osg has the option to cache nodes by using osgDB:Registry. Retrieving a node from the cache and attaching them to your subgraph is not threadsafe, because Node::addParent, Node::removeParent and Node::getParents is not threadsafe.
Consider this scenario: A node gets 'disposed' in the main thread, because the 'user' deatches the node from the graph. At the same time the node may be loaded from the cache by the databasepager. While the refcounting will work perfectly, the calls to Node::addParent and Node::removeParent is not threadsafe, causing the node to get an invalid parent setup. The same holds for StateSet and StateAttribute (because they have parentlinks as well). Example: The openflight loader stores static ref pointers to various StateAttributes. The StateAttribute::addParent and StateAttribute::removeParent may be called from multiple threads, i.e the main thread releases a model, while another thread (the databasepager) loads the model. Possible solution: Make the parent links threadsafe. For Statesets and StateAttributes I would remove them and implementing an "immutable" pattern instead. Richard Richard Schmidt System Designer EADS Deutschland GmbH Organisationseinheit (SDGE1) EADS Deutschland GmbH Registered Office: Ottobrunn District Court of Munich HRB107648 Chairman of the Supervisory Board: Dr. Thomas Enders Managing Directors: Dr. Stefan Zoller (chairman), Michael Hecht This E-mail And any attachment(s) to it are for the addressee's use only. It is strictly confidential and may contain legally privileged information. No confidentiality Or privilege is waived or lost by any mistransmission. If you are not the intended addressee, then please delete it from your system and notify the sender immediately. You are hereby notified that any use, disclosure, copying or any action taken in reliance on it is strictly prohibited and may be unlawful. - Thank you.
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