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JonnyW
02-01-2004, 01:17 AM
Hi,

I am having a bit of a problem completely understanding what the deal is being OpenGL and Linux (specifically RH9).

Do I "install" OpenGL? If not, how is OpenGL "already installed"?

Plus, I downloaded and installed Mesa, but, what the heck is Mesa, is it just the software linkup between OpenGL and the video card, or what? Does installing Mesa screw up OpenGL somehow? Considering I couldn't get any openGL programs to compile without installing Mesa, I am left to wonder.

Maybe I'm just entirely missing whats going on here, I don't really know.

Any clarification would be GREATLY appreciated. A big thanks in advance!

my system specs:
Redhat 9.0
Nvidia Geeforce4 Ti4200 128DDR (/w newest drivers installed)

JW

SatanicPezDispenser
02-01-2004, 08:54 AM
Yes, it is a stupid question, but at least you're honest about it. http://www.opengl.org/discussion_boards/ubb/tongue.gif

If you want to use OpenGL, you do need to install it, like you would anything else you wanted to use. BUT, since you have Mesa you don't need OpenGL, because Mesa is a clone of OpenGL, and, as far as I know, the two are compatible.

Usually, you don't have both installed because they use the same names and are installed in the same locations. There is a workaround for this, described at www.mesa3d.org, (http://www.mesa3d.org,) in case you want to compare the two using the same machine.

Now go read the tutorials and the online versions of the Red and Blue Books and work through them. The more of this you do, the clearer it'll all become. http://www.opengl.org/discussion_boards/ubb/smile.gif

-SPD

roffe
02-01-2004, 10:28 AM
Originally posted by JonnyW:
Any clarification would be GREATLY appreciated. A big thanks in advance!

my system specs:
Redhat 9.0
Nvidia Geeforce4 Ti4200 128DDR (/w newest drivers installed)

JW

Every major graphics card vendor usually ships OpenGL support with their drivers, this includes ATI and NVIDIA. What this means is that the necessary library files needed, at least for core OpenGL functionality, gets installed when you install the driver.

Mesa3D is also a graphics library identical to OpenGL. You would install Mesa3D for two reasons:

1) You don't have a graphics card that come with OpenGL support.

2) Your graphics card does support OpenGL to some amount but it might be outdated/buggy etc.

In your case, you have a graphics card that comes with good OpenGL support. You DO NOT need Mesa3D for CORE OpenGL support.

However, many apps out there use GLU, the OpenGL utility library, which if I remember correctly does not ship with ATI/NVIDIA drivers. This utility library ships with Mesa3D though, so you can use that.

You say you've installed the latest drivers. Have you verified that they work correctly?
An easy way to do this is to check if you have Direct Rendering enabled by running glxinfo.

pkaler
02-01-2004, 05:44 PM
Let me spell this out for you in crayon. http://www.opengl.org/discussion_boards/ubb/smile.gif

OpenGL is a specification.

Mesa is a software implementation of this specification.

Hardware vendors (eg. NVIDIA, ATI) implement the OpenGL specification in hardware. Ie. Their video cards.

To expose this implementation, you must install the driver for your particular video card.

Since you have a GeForce4, here is a link to the drivers that you need. http://www.nvidia.com/object/linux.html