Most video cards use an ICD(Installable Client Driver) for OpenGL. This plugs into the openGL library. The screensaver or whatever calls the openGL library and this routes the commands to the hardware accelerated code. That way your program doesn't care what video card is used.

Unfortunately, Voodoo1 and 2 can't run off of an ICD due to their architecture, so even though they run OpenGL they don't do it in the standard way. Alot of games have workarounds that call the Voodoo OpenGL routines (I even think I saw an article on how to do it on GameDev), but if the program assumes you're using OpenGL ICD's there's nothing you can do about it.

Well if you _really_ want to see it using your 3dfx card, get the current MiniGL .dll from 3dfx.com, rename it OpenGL32.dll, and put it in the same directory as your screensaver. If this is the Windows/System directory you shouldn't do this as you'll have to overwrite Windows OpenGL32.dll and strange results might occur. This method might not work as the screensaver may make OpenGL calls that are not supported in the MiniGL (that's why it's a MiniGL).

Consider yourself warned.

Just out of curiosity, do the MiniGL drivers work if you use wgl functions to initialize the OpenGL?

I hope someone can help me! I downloaded the OpenGL skyrocket screensaver but I can't seem to get an acceptable frame rate (it's appalling). I have a Voodoo2 Creative Labs 3d blaster card with 12MB but I'm sure it keeps trying to use my S3 Trio 64V+ display adapter to do all the OpenGL!! How do I tell Windows to use my Voodoo2? I have all the correct drivers installed. There's no card selection on the skyrocket savers setup!

Steve

get the new gl drivers from 3dfx.com. they were just released
11/3/99 and they are almost a full ICD implementation.