Excellent - that was all the explanation I needed. Everything is humming along just fine now.
Thanks, Paul! AC On 9/14/07, Paul Martz <[EMAIL PROTECTED]> wrote: > I'm not sure why you have a thread hung in drawImplementation() after > Viewer's destructor has been called. But I can explain some of the other > stuff you have questions on, and hopefully that'll help. > > > My question is, how do you guys > > normally deal with data (scene graph, geometry, text, > > whatever) being modified on the main thread while Viewer is > > apparently busy rendering the same data? > > Mark the Node or Drawable as DYNAMIC DataVariance, and only modify it during > the update traversal (or outside the rendering traversals). > > > Having looked at a lot of the other drawables included in > > OSG, I don't see how the "double buffering" scheme works -- > > how is that any of the scene graph or other geometry data get > > updated without creating a race condition like this? > > OSG operates on a gentleman's agreement under which you can do whatever you > want to DYNAMIC nodes during the update traversal, and OSG's possibly > multiple threads can perform read-only operations during the cull/draw > traversals. > > With osgViewer-based apps, marking nodes that you intend to modify as > DYNAMIC is critical, otherwise OSG might let the update traversal start (or > return from frame()) before it has finished processing the node that you're > going to modify. > > > What's the trick here? What > > can/can't one do from with the drawImplementation() method in > > order to remain thread safe? > > drawImplementation() should be const, so as long as you don't modify it or > anything else in the scene graph, you should be OK. > > Hope that helps. > > Paul Martz > Skew Matrix Software LLC > http://www.skew-matrix.com > 303 859 9466 > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
