Hi Robert, Thanks for that tip! It turns out that your suspicions were correct. I get the following output when I run my app:
Setting up osg::CameraNode::FRAME_BUFFER_OBJECT RenderStage::runCameraSetUp(), FBO setup failed, FBO status= 0x8cd9 OpenGL extension 'ARB_render_texture' is not supported. Failed to aquire Graphics Context Setting up osg::CameraNode::FRAME_BUFFER What I don't understand is how an nVidia 7800 card does not support the ARB_render_texture extension. :? My guess is that something isn't being configured correctly, or that the extension has been replaced with something else, or perhaps it is a driver bug. Any thoughts? The card isn't exactly a low-end card. I've also checked to see if WGL_ARB_render_texture is supported, and it isn't either. Thanks, Brian On Thu, 25 Jan 2007 08:57:03 +0000, "Robert Osfield" <[EMAIL PROTECTED]> wrote : > Hi Brian, > > How is the RTT being implementated? Are you sure its FBO? Running > use OSG_NOTIFY_LEVEL set to DEBUG will print out what path the OSG > uses for implementing the FBO. > > I have personally worked with FBO sizes way higher than window > resolution, all the way up to 4k x 4k without problem. I must admit I > have only done this with a full screen window, but I'd be very > surprised if its any different. > > From the description of the performance you a getting it I does kinda > sound like there issue with the OpenGL driver. > > Robert. > > On 24 Jan 2007 17:58:53 -0000, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > > > Hi Robert, > > > > Actually, I have discovered what my problem was. On two of the machines > > that I was testing on, their window dimensions were 640x480. My original > > test machine was 512x512. When I changed my test machine to 640x480, I saw > > the same drop in FPS on it as well. > > > > To my knowledge, I am not modifying the size of the 512x512 textures, so I > > am curious as to why increasing my window dimensions from 512x512 to > > 640x480 would cause such a drastic frame rate drop. :? The only thing > > that I can think of would be that since the initial RTT texture is smaller > > than the actual window dimensions, this imposes a performance hit when the > > render to texture actually occurs. Of course, that's just a stab in the > > dark. > > > > Can you think of any suggestions that I could try to get my framerate back > > up? The final window dimensions will ultimately need to be full screen, > > but that kind of frame rate hit (~2-3 FPS) will just kill any usability. > > Even having just one floating point texture at 512x512 drops the frame rate > > to around 20FPS for a full screen app. > > > > BTW, the final texture for the RTT is being rendered at 512x512, not full > > screen. It is a secondary view. > > > > Thanks, > > Brian > > > > > > > > On Wed, 24 Jan 2007 09:13:51 +0000, "Robert Osfield" > > <[EMAIL PROTECTED]> wrote : > > > > > Hi Brian & Jeremy > > > > > > I know this doesn't help you guys, but for the record I used Linux > > > almost everyday for the past 5 years, running with various NVidia > > > hardware + drivers and haven't ever come across changes in performance > > > w..r.t first boot up vs continued use. > > > > > > So its certainly possible to have OpenGL running near flawlessly year > > > after year. > > > > > > But... there are dodgey drivers around and it sounds like you guys > > > have got them installed, the quickest way to establish a pattern is to > > > publish what drivers you are have a problem with and see if others are > > > having the same problem. Try upgrading or stepping back driver > > > versions. > > > > > > NVidia have a set of forums that you could look at. I can't recally > > > the address but google will find it for you. > > > > > > Robert. > > > _______________________________________________ > > > osg-users mailing list > > > [email protected] > > > http://openscenegraph.net/mailman/listinfo/osg-users > > > http://www.openscenegraph.org/ > > > > > > > > > > > _______________________________________________ > > osg-users mailing list > > [email protected] > > http://openscenegraph.net/mailman/listinfo/osg-users > > http://www.openscenegraph.org/ > > > _______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ > > > _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
