oglbase-discuss,
Brian Paul writes:
> I'm in favor of this. It would help with portability and doesn't appear
> to have any downsides (if you don't like GL_HAS_GLEXT you can ignore its
> existance).
>
> As Steve said, autoconf could detect glext.h. But not everyone uses
autoconf.
Yes, autoconf is only a solution for autoconf users. Users of
Imakefiles and simple Makefiles would be left in the cold.
While the focus of oglbase-discuss is for Linux installations, we
shouldn't lose sight of the fact that other OpenGL development
environments are likely to follow any <GL/glext.h> standard established
by oglbase-discuss. The simple portable GL_HAS_GLEXT mechanism
seems simple enough and does not depend on autoconf.
Stephen Baker writes:
> Indeed - but it's also possible that someone might want to download
> GL/glext.h to use it with an older GL/gl.h that doesn't know about
> your GL_HAS_GLEXT...well actually I'm not sure if that's 100%
> reasonable.
At least there is no compile-time error. And if you compile with
a <GL/gl.h> that doesn't define GL_HAS_GLEXT, the implication is
that you don't expect a <GL/glext.h> to exist. The point is exactly
that portable compile-time error-free OpenGL source code can be
written to handle environments that do not define GL_HAS_GLEXT such as
compiling with an old <GL/gl.h>.
Stephen Baker writes:
> (Since it's an extension, shouldn't that be GL_HAS_GLEXT_EXT :-)
In case you weren't joking, GL_HAS_GLEXT is not part of
any extension. It is simply a convention. There's no need to
make GL_HAS_GLEXT any longer than it is.
- Mark
