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opcode
10-31-2004, 08:06 AM
Could someone help sort me out on this?

I'm looking at the gl.h file that came with visual c++ 6.0. I'm seeing a BUILD version of 0004. Now, obvously, this will change as time goes by. Where can I download the latest source code?

Wouldn't be in SGI's best interest to to maintain the source code for win32 and linux. I've been using the mesa libraries for a while now. What version are we at now? I just don't understand how we can all be on the same page if were all using different versions of the source files which make the all important calls to the GPU.

What am I missing here?

ZbuffeR
10-31-2004, 09:11 AM
Read the FAQ :
http://opengl.org/resources/faq/getting_started.html

Basically the OpenGl headers are split in two, gl.h for opengl up to version 1.1 and glext.h for everything else.

About the actual calls to the GPU, they are not done by the headers nor the lib files, but by the actual video driver when the app is running.
That is why you have to check at runtime if a particular GL extension is available (either do it by hand or use an extension library).

opcode
10-31-2004, 11:04 AM
Thanks alot ZbuffeR, I've been using OpenGL for a while now, but I've never gotten a grasp of the big picture, thanks for the start.

About the openGL calls. The library calls we make in our source code, makes calls to the driver, which in turn makes the call to the GPU? Is this correct?

How about shader, when we tell the GPU to compile the code, and even run the code, are those calls made through the driver as well?

Also, am I to assume that my win32 gl.h is the same as everyone elses. I actually have to include glut.h after gl.h to get my program to compile, even though I don't use any calls from glut.h. I think it's a problem in the version of gl.h I have so I was hoping to download another one.

ZbuffeR
10-31-2004, 01:47 PM
The library calls we make in our source code, makes calls to the driver, which in turn makes the call to the GPU? Is this correct?Correct. The video driver has a GL API implementation.


How about shader, when we tell the GPU to compile the code, and even run the code, are those calls made through the driver as well?To be more precise, you ask OpenGL to compile the code, so the driver will do this compilation (on cpu) and will send to the card hardware-specific opcodes and such.


Also, am I to assume that my win32 gl.h is the same as everyone elses. I actually have to include glut.h after gl.h to get my program to compile, even though I don't use any calls from glut.h. I think it's a problem in the version of gl.h I have so I was hoping to download another one.What sorts of compile errors ? Well, maybe you need to include windows.h before gl.h, or whatever. There are some details about that on the technical FAQs, around the link I gave.
You may want to use the gl.h from nvidia sdk, you will find it in their website. Or even from MESA.

opcode
10-31-2004, 03:11 PM
ZbufferR, once again I thank you. I was able to get the newest gl headers from nvidia. I was looking for the header files on SGI's site. For whatever reason I thought they would be the keepers of the flame so to speak.

My engine built right away after I got the new headers.