what's mcd,icd and turbo gl ??

[blades]

and what does that relate to games?? please explain in human language and how does that improve my games?

[Kruzin]

The things you mention are all related to OpenGL. Only games (like quake1,2,3) that use OpenGL are affected by these.

OpenGL is a graphics API (or language), like Direct3D or Glide.

An ICD (installable client driver) is a "translator" to get an app or game to communicate with your video card in the OpenGL API.

An MCD (mini client driver) is a stripped down version of an ICD, containing only the OpenGL calls needed to run a game (OpenGL is used for much more than games). By striiping it down, and streamlining the driver, an MCD is usually faster than an ICD, but can only be used for games, not full-blown OGL apps.

TurboGL is Matrox's name for their MCD.

[paulcs]

Think of them as drivers that make your 3D games work.

Sometimes we like to call these API's (application programming interface). There are three API's used for games.

Direct3D or D3D: This API was invented by Microsoft as part of their plan for world domination. Most games use Direct3D.

OpenGL: This is an "open graphics library" developed by Silicon Graphics (SGI) to keep the world safe for democracy. It is used primarily for graphics applications, but it is also used in games that use the Quake 2, Quake 3, and other game engines. I hear it is very easy to write code using OpenGL, but a real pain in the butt to write drivers.

The driver required to run OpenGL apps and games is called an ICD (Installable Client Driver).

Here's a list of games that use the OpenGL API:

http://home.pacbell.net/freundj/openglgames/

Glide: This is an API developed and, until very recently, proprietary to 3dfx. Some games, like many flight sims and Unreal Tournement, were written with Glide as the primary API. In these cases, D3D and/or OpenGL capability is added later so non-Voodoo boards can run them.

Games based on the Quake 2 engine, as I mentioned before, use the OpenGL API. Until recently, Voodoo boards didn't support OpenGL. Instead, the used an MCD that translated OpenGL calls into something Glide could understand. This is called a MiniGL.

MCD is kind of like a MiniGL, in that the "M" stands for "mini." However, it actually uses OpenGL. It is usually optimized specifically for games and doesn't run applications. I guess Matrox felt their ICD was a little slow, so while they were working on something faster, they gave us TurboGL, an MCD. Until recently, it was faster than the ICD in lower resolutions.

Paul
paulcs@flashcom.net

[paulcs]

Damn! Kruzin beat me to it again!

Paul
paulcs@flashcom.net

[Maggi]

Boy, I wish somebody had the time to collect all those gems ...

Nice draw, dudes !



------------------

[blades]

thanks for the replies i feel enlightened

so it would be better to use turbogl instead of icd ?


[This message has been edited by blades (edited 13 February 2000).]

[Maggi]

Hi Blades,

that depends on your purposes and system ...

If you have a SS7 MoBo and a K6-x CPU, you should use PD5.30 with the TurboGL.
When you're BX based with an Intel CPU, you should try PD5.50 which seems to be even faster than the TurboGL in some situations.

Athlon based systems ... can't tell, sorry

[PaulS]

You guys are confusing everybody. Forget the initials, in Windows an MCD is taken as the MS version (that vendors modify slightly).

Matrox has an MCD, an ICD and a minidriver (TurboGL). The TurboGL is not the same as the MCD, and no vendor would ever call their windows OpenGL miniport an MCD.

Paul

[absalom]

heh, the things I stir up

[PaulS]

Troublemaker!

Actually, I thought of a better explanation. Both an MCD and an ICD conform to and require WindowsGL (wgl). If you attach a debugger to an ICD or MCD they should be using the MS OpenGL dll's. A miniport will skip this completely, it doesn't matter whether wgl is present or not, they skip the driver bit and allow an application to link directly to a substitute opengl.dll

So the MCD and ICD have access to full wgl library, and implement what they like in hardware. However, the miniport won't have software emulation for unsupported functions because it doesn't use wgl.

Paul