History:
Glide is essentially OpenGL... However it was cutdown and reprogrammed to be smaller and 3dFX specific, and not just 3dFX specific but actually Voodoo Specific.
Glide2x covers Voodoo2|Banshee
Glide3 covers Voodoo3+
Now although Glide Wrappers developed for N64 High Level Emulators will wrap Glide Functions -> OpenGL 1.0
They don't do a complete job, infact are quite buggy, unrelyable and specifically built for specific N64 games and Glide Functions that will be run.
If you wish to have a true Glide -> OpenGL or -> DirectX wrapper DLL. I would suggest looking on the internet for 3dFX's SDK (which is now free and available but where i can't remember) and then reprogramming a Glide.DLL which you install specifically to use OpenGL|DirectX.
However for this to be truely sucessful you will have to compensate for the differences and what the original driver will be looking for from the Glide Drivers rather than what it will be asking the card to do. I know that doesn't make alot of sense right now but once you get into researching this then you'll understand.
I'd personally ask about the C++ development forums, especially the game ones ... as many people getting into OpenGL love a challenge.
Anata aru kowagaru no watashi!