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rm3
09-22-2002, 08:13 AM
I have a question about something that is bugging me... Games that, I am told, use OpenGL, such as quakegl and Half-Life, run very fast on my system. (I have a Compaq, AMD k6-2 450 mhz, with a Rage LT Pro AGP 2x graphics card, at 800x600 resolution and 32-bit color depth). However, many simple OpenGL-written applications, such as PongMania from the OpenGL Game Programming book's disc, or any of NeHe's examples, run very choppily and slow unless the window size is very small, and fullscreen cannot be set either.

What I'm wondering is if this is just the way it is- that those professional companies add some magic spice to their OGL code that makes, despite all the complex rendering, it run at lightspeed frame rates that all other OGL demos can't come close to, or am I doing something wrong? Is there anything I can do to make it run faster?

I would greatly appreciate any help. Sorry if this turns out to be a stupid question, but I can't learn OpenGL very smoothly if I get what seems like a 5-fps rate on a rotating triangle...

09-22-2002, 10:01 AM
You should definitely be getting hundreds of frames per second on avg on most of NeHe's tutorial examples. i have a comparible system to yours. Celeron 366 overclocked to 412 (75mghz FSB) 32 MB Geforce 256 video card.

Something is wrong with your setup there tho I don't know what. Wish I could help further, but just letting you know it is nothing special those comanies are doing, although they do have optimisations galore at their disposal but so do you. You really don't need much in the way of optimisations for a couple of dancing triangles or most of NeHe's tuts tho. And even if you did use any special optimisations on such simple examples it would only amount to just a few fps, not much of a difference really.

Hopefully someone that has experianced something similar can help you out on what to do to get your OpenGL programs running properly on your rig.

harsman
09-22-2002, 10:28 AM
Those systems are not even remotely comparable. The ATI Rage Pro LT had really crappy OpenGL support last time I checked. When I had one, even the Direct3D drivers where so buggy most Direct3D6 games didn't work. Software rendering was usually the fastest alternative. If you want to get any speed at all out of that card you probably need to run in full screen 640x480 at 16 bit colour with 16 bit textures. It probably can't handle all blending modes in hardware either. The GeForce 256 is an OpenGL performance monster in comparison.

09-22-2002, 11:01 AM
Sorry I was under the mistaken impression that the Rage series cards had Nvidia Riva 128 like chipsets. My mistake. When he said he ran GLQuake and Half Life I thought he was running in OpenGL mode and not software rendering.