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05-31-2000, 10:38 AM
how do I use extensions, do I have to download something else or no?

Bob
05-31-2000, 10:42 AM
Depends on what platform you are coding for, but generaly, no, you don't have to download anything, except a document or two that explains how to use the extension if you want them. Tell me whan platform you are using and maybe i can tell you how.

05-31-2000, 03:05 PM
I am working on all platforms actually, that is except macintosh, but mainly on wnt4

Bob
06-01-2000, 02:42 AM
In Win32 version of gl.h there are some macros defined (almost in the bottom of the file) called PFN*PROC, these macros defines a functionpointer you can use to access extensions. An example:

PFNGLARRAYELEMENTEXTPROC glArrayElementPtr;
glArrayElementPtr=(PFNGLARRAYELEMENTEXTPROC)wglGet ProcAddress("glArrayElementEXT");

Then you have to check if we got a proper poiner, like this:
if(!glArrayElementPtr) exit(1)

If this passed, you can now use your extension like this:
(*glArrayElementPtr)(i);
Maybe even like a standar function too, not sure, glArrayElementPtr(i);

You have to check out your copy of gl.h to see what extensions are predefined. If you are looking for other extensions, just have alook at the extension registry ( http://oss.sgi.com/projects/ogl-sample/registry/ ) and look at the extesion you want. There you can find the exact prototype of all extension aswell as a description of them.

Using extesion under UNIX is nothing I know about, but keep on asking and you will get an answer.