Please explain difference between Direct 3D and Open GL

Thanks. My system specs are fairly high end and the video card certainly is. So how will I know just which setting to use for which game? MOHAA for instance or Morrowwind, Ghost Recon, Return to Castle Wolfenstein? Where do I go to look whether to set 3D or Open GL settings? Is there ever a case where they should both be turned up in both tabs?

In the most basic terms, OpenGL and Direct3d are differing API's (Application Program Interface) for rendering 3d graphics. Some games like Quake 3, use OpenGL, other games like Unreal Tournament, use Direct3d. Setting your AA and AF in Direct3d will only effect games that are Direct3d, same for OpenGL. You should be aware that jacking up AA and AF will lower frame rates. If you have a high performance system with a top notch video card you can still get playable frame rates with higher AA and Af settings, depending on your display resolution. A slower system will choke on high AA and AF settings.  

Message Edited by jakeleg on 02-27-2003 12:24 PM

You don't have to make any setting to tell your game to use OpenGL or Direct3d. A Direct3d game will automatically use whatever setting you have in the Direct3d tab in your control panel, it will ignore any OpenGL settings. Same goes for OpenGL games (There are a few games that you can play in either OpenGL or Direct3d, but that would be an in-game option setting) MOHAA and RTCW are OpenGL and I believe that Ghost Recon is Direct3d. To find out what game is which, you should find game specs on the box or the booklet. You can also find game profiles here:

http://www.gamespy.com/games/

 

 

Thanks! And how would I go about measuring frame rates during game play?

Some games like Q3 and UT2003 have integral benchmarking capabilities. There are  programs available  that will record framerates in your games, but I'd don't use them so can't give you any recommendations. Try posting the question in the Video or the new Gaming forums.