Hi Ufuk? Gun? (Could you please sign with your first name so we can adddress you correctly)
On Wed, Feb 4, 2009 at 2:54 PM, ufuk gun <[email protected]> wrote: > Hi, > I have to do a simulation project which needs 8 screens. This system likes a > dome. > > so i want to ask few questions about this: > > 1) i want to use multiple gpu's. So is there a limit on number of gpu's on a > pc? i saw 4 gpu's on a pc and every gpu has 2 outputs. can i render 8 screen > with viewer? Yes, osgViewer support novel camera/display combinations, including support for multi-threading. There is a video on youtube of FlightGear running on an 8 screen powerwall all driven from a single PC. I'm afriad I don't have the refernece off hand. I've personally driven four outputs from a single PC using two cards. Scaling up much higher will hit PC hardware/driver bottlenecks. If you are doing a dome, then could also do the distortion correction using the OSG - see the osgViewer::setUpViewFor3DSphericalDisplay(), this uses 6 RTT cameras rendering to a cube map, and a single Camera/subgraph that does the distortion correction. This setup only generates a single output for a fish eye lens, so not an exact match for your requirements but it might give up an idea of how to set up the various slave cameras to do combinations of distortion correction. > 2) how can i set which gpu render which screen. is there an auto management > system in viewer? if i have screens which have resolutions like 8x1280x1024 > or 4x2560x1024 or any other combination of this, should i do an extra thing > for this? You just assign the screen number to the GraphicsContext::Traits when setting up the various GraphicsContexts. See the osgcamera example for an example of use Traits to describe your window setup. FYI, Windows is less well suited for this type of multi-screen output, as the drivers try to a bit bit too clever for their own good, duplicating OpenGL calls across contexts. Unices (including Linux) that use X11 work great on complex multi-screen setups as you get exactly what you ask for in terms of screen to GPU mapping. > 3) do you think i will have a critical frame rate problem if i render 8 > screens. That all depends upon your scene, and your hardware, and your frame-rate needs. It's doable but.. to get the performance you might need to use a cluster rather than a single machine. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
