Hi Mike, The ReadFileCallback is an ideal place to modify the loaded scene graph as it's called from the database thread so won't impact the rendering performance. The only problem is that you are wanting to know where the loaded subgraph will be attached to the scene graph.
The only info available about this in the ReadFileCallback is the Terrain pointer that the DatabasePager passes into the read call via the Options object. This Terrain pointer isn't the exact position the subgraph will be inserted, but for the purpose of osgTerrain it's sufficient for finding neighbouring tiles etc. to help with the tessellation process. Providing the NodePath for the insertion point from the DatabasePager to the Options object to read operation is something I looked at previous, but this wasn't thread safe as the NodePath itself can become invalidated by other threads - sometimes the DatabasePager has to deal with the node it intends to add the new subgraph to have been already deleted, so has to discard to the new subgraph. One option open to you could be to subclass from DatabasePager and override the updateSceneGraph(..) method. Unfortunately this would be an operation done in the main thread so you'd need to be careful about the costs involved. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
