Open GL. Direct X. How do they compare?

[Jayce]

I've googled a lot but I'm finding a lot of web sites go so in depth and have so many detailed involved that I can't seem to find a straight answer.

Basically what I've gathered is this...

Direct X = Microsoft Product.
OpenGL = Open Source Product.

Therefore, by nature it's expected that Ubuntu works with OpenGL. Okay, great.

I'm confused, though. How do they compare in terms of performance? Also, are graphics cards natively supported by both? Or if you want to play native Linux games with OpenGL, do you have to get a card specifically supported by OpenGL?

 

[CalcProgrammer1]

Windows uses OpenGL AND DirectX. DirectX and OpenGL are both 3d graphics and video libraries that enable hardware-accelerated graphics and video. DirectX is made by Microsoft and OpenGL is open source. Graphics cards support both OpenGL and DirectX, but newer DirectX releases (DX10) require extra hardware features that aren't yet supported by OpenGL (I've heard that there are some unofficial versions that support DX10 hardware functions, but normal installations don't). All major cards (ATi, nVidia, Intel, etc) support OpenGL and will play games in Linux just fine (as long as they are OpenGL games, WINE + DirectX games will have to be emulated to OpenGL, you can't run DirectX natively in Linux as the drivers don't support it).

 

[Jayce]

So say you had a computer, XP/Ubuntu, and a game that is supported in both Linux and Windows, such as Quake or something like that... oh, and your graphics card was say... Nvidia... that supported OpenGL and Direct X.

In terms of the same hardware given, same game, etc etc... would there be a significant difference in performance between OpenGL and Direct X? I'm just trying to get an idea of how they stack against one another.

Also - I assume that if you buy a game for Linux, it'll have to be an OpenGL game... so if I were to walk in a store full of Linux games, as long as it was Linux, then it'd safe to presume it's OpenGL supported.

Eh?