On Sat, 11 Sep 1999, Bernd Kreimeier wrote:
> Exactly. So intead of one entry point, we have several.
>
> > I'm in favor of separate glGetProcAddressEXT, gluGetProcAddressEXT,
> > glxGetProcAddress, etc functions.
>
> There has to be a good technical reason then why
> glxGetProcAddress isn't sufficient?
Yes, two reasons I think:
1) A program may choose not to link to glu. Hence
glxGetProcAddress cannot tell the address of
a glu function by having code like:
if ( strcmp ( s, "gluEndCurve" ) ) return gluEndCurve ;
...so glu functions have to be interrogated by gluGetFuncAddressEXT
Similarly, it is still desired by some people to use OpenGL
under Linux without X. Those people won't take kindly to
the inability to query gl functions because the query
routine is in glX.
2) We might fondly imagine a day when this extension
is universally adopted - even under Windoze, Apple, OS/2
implementations.
When that happens, portable programs will be able to call
glGetFuncAddress and gluGetFuncAddress without nasty compile
time hacks...In fact, the only time you'd need such hacks
would be if you needed to check for glX/agl/pgl or wgl
extensions...which are by definition not portable anyway.
I think it's worth the tiny amount of extra hassle to
keep things clean.
You can still legally say:
#ifndef WINDOZE
void *wglGetFuncAddress ( char *s )
{
void *f ;
if(!(f= glGetFuncAddress(s))) return f;
if(!(f=gluGetFuncAddress(s))) return f;
#ifdef X_WIN
if(!(f=glXGetFuncAddress(s))) return f;
#endif
#ifdef MAC_OS
if(!(f=aglGetFuncAddress(s))) return f;
#endif
#ifdef OS2
if(!(f=pglGetFuncAddress(s))) return f;
#endif
return NULL ;
}
#endif
...which covers all the bases in the meantime.
Steve Baker (817)619-2657 (Vox/Vox-Mail)
Raytheon Systems Inc. (817)619-2466 (Fax)
Work: [EMAIL PROTECTED] http://www.hti.com
Home: [EMAIL PROTECTED] http://web2.airmail.net/sjbaker1
