OpenGL
After DirectX, OpenGL is the next most popular 3D API. It has existed for far longer than DirectX, and is available for a large number of operating systems. DirectX, on the other hand, is confined to Microsoft platforms.
Like DirectX, OpenGL is constantly being refined, updated and extended in its capabilities. Also like DirectX, it is supported by virtually every current 3D graphics card. Furthermore, the newest 3D features can usually also be implemented in OpenGL, even if these features have not yet been defined in the OpenGL standard; these are called OpenGL extensions . Frequently, graphics chip makers will offer their own extensions in drivers for certain effects that can be employed by applications or games. The two industry heavyweights, ATI and NVIDIA, offer very good OpenGL support, so there's not much to worry about there. Things aren't quite as rosy in the case of XGI and S3, however, which still have some room for improvement in their drivers.
Despite the seeming dominance of DirectX titles, there are still many games that are programmed for OpenGL. The most well known among these are the titles published by the Texan game designer id Software; many other game developers have also licensed 3D game engines from id to use in their own software. The newest and definitely most demanding OpenGL game from id is the first person shooter Doom III. NVIDIA cards perform especially well running this game, closely followed by ATI's offerings. The game will also run on XGI cards, with some effort and at reduced quality settings. For its part, S3 has published a special Doom III driver.
Interested readers can find more information on OpenGL at opengl.org .
Other Operating Systems
Things get more complicated for operating systems other than Microsoft Windows. The various cards' 3D performance under Linux differs drastically from that in Windows. Both ATI and NVIDIA support Linux with special drivers.
More information on Linux and graphics cards:
- ATI Linux Drivers FAQ
- HOWTO: Installation Instructions for the ATI Proprietary Linux Driver
- NVIDIA Linux Advantage PDF
- NVIDIA Linux Driver Forum @ NVNews
Linux drivers can be found on ATI's and NVIDIA's download pages.
