Re: [oglbase-discuss] OK, back to Re: 2nd draft:GL_EXT_get_proc_address spec

[Stephen J Baker]

On Thu, 14 Oct 1999, Paul Miller wrote:

> My application is smart enough to put the typical controls on the
> "typical" card, and the fancy super-high-res deep-pixel image processing
> windows on the "fancy" card. Naturally I'm interested in whatever
> extensions are present in the fancy card such as MultiTexture and the
> future SeparateAlphaBlendMode extension.
> 
> Since I have these different windows, I would expect to be able to get
> different features/extensions from the different contexts. What would
> happen when I query the extensions with context-independent function
> pointers? Assuming I get a pointer, what happens when I call it?
 
Not a problem.

We already specified that the GetProcAddress function is NOT
for querying the existance of a function - only for getting the
address of a function that's already known to exist.

Hence, you should test for the presence of extensions using
the regular glGetString ( GL_EXTENSIONS ) mechanism (which
is still context-specific).  Only IF the extension is known
to exist in one or more of the contexts should you ask for the
address of that function.

Steve Baker                (817)619-2657 (Vox/Vox-Mail)
Raytheon Systems Inc.      (817)619-2466 (Fax)
Work: [EMAIL PROTECTED]      http://www.hti.com
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