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charliejay
02-24-2005, 01:02 AM
Hi all,

I'm using a Radeon 9200 Mobility, OpenGL 1.3 (and Mac OS X 10.3.6, if it matters).

The question I have is this:

The hardware accelerated renderer advertises ARB_shader_objects, ARB_fragment_shader, and ARB_vertex_shader, all of which say that they "require OpenGL 1.0" but are "written against the OpenGL 1.4 specification".

So, given that I have OpenGL 1.3, does this mean I can use gslang shaders, or that I can't?

Thanks, Charlie

Relic
02-24-2005, 04:30 AM
"Written against an OpenGL version" just means you take the spec text of that OpenGL version and update the chapters changed in the extension spec to get the full documentation in context.
This has nothing to do with the version number your OpenGL implementation returns. If the extension strings you need are reported, you should be able to load all function entry points of those extensions and you can start to use it.

charliejay
02-24-2005, 04:51 AM
Thanks for clarifying that for me, Relic.

One further thing, what isn't advertised, is GL_ARB_shading_language_100.

How does that affect things?

Thanks again, Charlie

Relic
02-24-2005, 11:17 PM
GL_ARB_shading_language_100 is probably the short lived "extension" ever. It does nothing else than to tell that the GLSL version implemented supports the spec version 1.00.
OpenGL 2.0 has a decent GLSL version info mechanism now.
If you have the other three extensions, you have the necessary interface to start with GLSL.
(Check out the shading language forum on this site if you run into trouble.)

charliejay
02-25-2005, 12:30 AM
That's excellent news...

Cheers, Charlie