How glutGameMode call my gfx card?

I run my previous glut project on WinXP. But my projects are not accelerated by my Vodoo3. This not happend on Win98.
Then I try running several games and they are accelerated. What I mean is the game can detect my gfx card.

What I think is glutGameMode automatically detect my gfx card and use it. And I’ve see somewhere something call LCD (if I’m not mistaken). What is LCD? Is it related to my problem? Are the games that I play not using LCD? Are all opengl program use LCD?

Originally posted by Binqay:
[b]I run my previous glut project on WinXP. But my projects are not accelerated by my Vodoo3. This not happend on Win98.
Then I try running several games and they are accelerated. What I mean is the game can detect my gfx card.

What I think is glutGameMode automatically detect my gfx card and use it. And I’ve see somewhere something call LCD (if I’m not mistaken). What is LCD? Is it related to my problem? Are the games that I play not using LCD? Are all opengl program use LCD?
[/b]

I think you are refering to “ICD” (not LCD), which means Installable Client Driver (I think). Anyway - an ICD is a complete OpenGL implementation taylored for your card (i.e. the OpenGL driver for your card). If, for some reason, your card is not compatible with the video/OpenGL mode you are running, the ICD may not be used - you fall back to the non-accelerated M$ software implementation.

So - my guess is that you are using a 32-bit color mode in your fullscreen app, while Voodoo3 only supports 16-bit color.

You may want to use this program to test your fullscreen capabilities in different modes (of course, it uses GLFW , not GLUT, and the source is included).

It is a console application, so run it from a command prompt (you’ll get usage info). Actual stats (acceleration, resolution, depth) are printed to the console.

[This message has been edited by marcus256 (edited 03-04-2002).]

I got 2 version of Vodoo3 driver. One came with the box while the other one I got from my friend. Using the first one, I can’t find the “ICD” in windows system while the other one yes. So is that mean “ICD” is not a must for running OpenGL application?

Are the other OpenGL application(not using GLUT) call the same “ICD”? Or they never call it(ICD)?

The ICD, if present, is automatically used whenever possible for OpenGL rendering. It is handled automatically by Microsofts OpenGL interface. If it is not present, Microsofts (old and slow) software OpenGL implementation will be used instead. The software (regardless if it uses GLUT or anything else) has no control over this (other than perhaps using video modes that are supported in hardware).

You can:

printf( "Vendor: %s
", glGetString( GL_VENDOR );

to see if you are using an ICD. If not, you will see “Microsoft”… something printed. If you have an ICD for Voodoo3, you will probably see “3Dfx”… something. (you need to have opened your OpenGL window before doing the above).