Thanks for the culling mode tip Robert. My terrain was generated using VirtualPlanet builder, but I didn't do it, so I'll get back to you when I get more details on that. I'm running my application on 2 machines getting similar results: a 64-bit-Linux-86 with a double headed Nvidia Quadro 3450. The other is an intel MacBook Pro with a GForce 8600. The available RAM for both is way over 1GB. I am trying OSG 2.6.0. It usually runs smoothly at 60fps, but on this particular terrain, when zoomed in, and at angles on which I look far into the distance, the framerate drops to below 20, which is unacceptable for my application. I believe I end up drawing way too many triangles for the computer to handle efficiently. I am trying to find ways to run at a solid 60fps no matter what.
-Jose On Wed, September 10, 2008 12:56 am, Robert Osfield wrote: > Hi Joseanibal, > > By default the OSG does not cull on the near/far planes, and near/far > clipping is done down on the GPU only affect the fill rate performance > of your application. You can enable culling on the near/far planes, > but you have to be careful about setting your near/far planes so that > encompass your scene - as the OSG by default computes the near/far > planes it'll hide the inappropriately set near/far planes so by > toggling these features on you might suddenly find parts of foreground > or distance disappearing. > > To switch off the compute of near far use the Camera methods > (inherited from osg::CullSettings) : > > > viewer.getCamera()->setComputeNearFarMode(osg::CullSettings::DO_NOT_COMPUTE_NEAR_FAR) > > To enable the culling against the far plane use methods inherited from > osg::CullSettings again: > > int cullingMode = viewer.getCamera()->getCullingMode() | > osg::CullSettings::FAR_PLANE_CULLING; > viewer.getCamera()->setCullingMode(cullingMode); > > All of this doesn't really address the performance issue too much. > You don't mention the nature of your database at all i.e. how you > built it, what scene graph components it uses, or what hardware, or > OS, or OSG version you are using, all this info is essential for > others to know enough to really guide you in the right direction. > > Robert. > > > On Wed, Sep 10, 2008 at 1:08 AM, Joseanibal Colon Ramos > <[EMAIL PROTECTED]> wrote: >> Hi all, >> >> I was hoping someone has an idea about why I am encountering the >> following >> problem: I have a big terrain and on certain viewing angles it contains >> a >> huge amount of triangles to draw and puts a big strain on OSG's >> performance. I tried playing around with near/far clipping planes to >> improve performance, by cutting out a lot of the rendering, to the point >> only a very small fraction (and even none at all) of the terrain is seen >> through my camera. OSG's framerate, however, behaves just as if I was >> looking at the whole thing and drawing all the triangles. >> >> At certain angles, the framerate increases (where small number of >> triangles would normally be - even thought I don't see anything), >> >> and at other angles, it decreases (the same angles at which the viewer >> normally tries to draw a large number of triangles - even though I can't >> see anything). What is going on here?!? help! >> >> -J >> >> _______________________________________________ >> osg-users mailing list >> osg-users@lists.openscenegraph.org >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
