Hi Frank, By default OSG only enables culling from the sides of the view frustum, so doesn't doing any scene graph level culling for the far plane. This default is required because by default the OSG also computes the near and far planes on each frame based on what objects are in the view frustum. The two defaults together mean that the if in object is in front of the camera it will be seen regardless of size of the scene. This provides good out of the box experience for majority of users.
If you don't have the compute near/far planes enabled, and define them stricky yourself by setting the camera's projection matrix then you can also enable the far plane culling. The appropriate settings can all be found in osg::CullSettings, osg::Camera inherits from this so you can just set everything via the viewer's Camera. Robert. On Tue, Dec 14, 2010 at 4:03 PM, Frank Sullivan <[email protected]> wrote: > Hello, > > I can tell that my OSG-based app is doing some sort of frustum culling, > because if I take the camera to the edge of the scene, and I turn it such > that it isn't looking at anything, the frame rate jumps to 500fps. However, > when I turn back around to look at my scene, the frame rate drops to about > 60fps. > > One thing I found interesting, though, is that this doesn't seem to work for > the far plane. If I aim my camera towards the scene, and I pull back until > the entire scene disappears beyond the far plane, my frame rate remains at > about 50-60fps. > > Does anyone know why this is happening, and if there is a way to fix it? > > Thanks, > Frank > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=34841#34841 > > > > > > _______________________________________________ > 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
