Hi Robert, our databases are for driving simulation and they are usually city streets. We have been employing batching and occlusion culling with very good results so far.
Extensive use of LOD's is problematic because 1- They actually reduce performance in most of the cases 2- The switching effect (even the slightest) is found very disturbing by the customers. So with LOD's we are somewhat conservative (but we use them nevertheless) Actually, draw always required more time than cull. If you look OSG examples, draw usually takes more time than cull. Now that draw reaches 16 ms border, this started to hurt us. I think I should retract my sentence from previous email. Draw is not slowing down faster than cull; I did not really make such an observation. My actual observation is that, both cull and draw require more CPU time with larger scenes, but since draw is generally more performance hungry, it becomes bottleneck earlier. tugkan > Hi Tugkan, > > On Wed, Aug 18, 2010 at 9:49 AM, Tugkan Calapoglu <tug...@vires.com> wrote: >> We observe that, as our databases grow, the performance requirement for >> draw thread grows faster than cull. In the long run, draw will be a >> serious limiting factor for us. So I wanted to see if we can take >> advantage of hardware to solve the problem. > > Does this not point out that perhaps the scene graph is become less > well balanced over time? > > I'd look closely at what in the draw dispatch is becoming the > bottleneck and how to manage this more efficient. Typically the best > way to reduce draw dispatch is to batch the geometry and state in more > coarsed grained way. One can also use different approaches to achieve > the same/similar results. For instance perhaps you can cull more > effectively, or perhaps introduce LOD more effectively. > > Robert. > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > -- Tugkan Calapoglu ------------------------------------- VIRES Simulationstechnologie GmbH Oberaustrasse 34 83026 Rosenheim Germany phone +49.8031.463641 fax +49.8031.463645 email tug...@vires.com internet www.vires.com ------------------------------------- Sitz der Gesellschaft: Rosenheim Handelsregister Traunstein HRB 10410 Geschaeftsfuehrer: Marius Dupuis Wunibald Karl ------------------------------------- _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
