@node ax_check_glu
@unnumberedsec ax_check_glu

@majorheading Synopsis

@smallexample
AX_CHECK_GLU([ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
@end smallexample

@majorheading Description

Checks for GLUT. If a valid GLU implementation is found, the configure
script would export the C preprocessor symbol "HAVE_GLU=1".

If either a valid GLU header or library was not found, by default the
configure script would exit on error. This behavior can be overwritten
by providing a custom "ACTION-IF-NOT-FOUND" hook.

If the header, library was found, and been tested for compiling and
linking the configuration would export the required compiler flags to
"GLU_CFLAGS" and "GLU_LIBS" environment variables. These two variables
can also be overwritten by defining the environment variables before
executing the configure program. If it was predefined, configure would
not try to overwrite it, but it would still perform the compile and link
test. Only when the tests succeeded does the configure script to export
"HAVE_GLU=1" and to run "ACTION-IF-FOUND" hook.

If user didn't specify the "ACTION-IF-FOUND" hook, the configuration
would prepend "GLU_CFLAGS" and "GLU_LIBS" to "CFLAGS" and "LIBS", like
many other autoconf macros do.

If the header "GL/glu.h" is found, "HAVE_GL_GLU_H" is defined. If the
header "OpenGL/glu.h" is found, HAVE_OPENGL_GLU_H is defined.

You should use something like this in your headers:

@smallexample
  # if defined(HAVE_WINDOWS_H) && defined(_WIN32)
  #  include <windows.h>
  # endif
  # if defined(HAVE_GL_GLU_H)
  #  include <GL/glu.h>
  # elif defined(HAVE_OPENGL_GLU_H)
  #  include <OpenGL/glu.h>
  # else
  #  error no glu.h
  # endif
@end smallexample

On the OSX platform, you can use the option --with-xquartz-gl to use
X11/Xquartz GLU implementation instead of the system built in GLU
framework.

Some implementations (in particular, some versions of Mac OS X) are
known to treat the GLU tesselator callback function type as "GLvoid
(*)(...)" rather than the standard "GLvoid (*)()". If the former
condition is detected, this macro defines "HAVE_VARARGS_GLU_TESSCB".

@majorheading Source Code

Download the
@uref{http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_check_glu.m4,latest
version of @file{ax_check_glu.m4}} or browse
@uref{http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=history;f=m4/ax_check_glu.m4,the
macro's revision history}.

@majorheading License

@w{Copyright @copyright{} 2009 Braden McDaniel @email{braden@@endoframe.com}} @* @w{Copyright @copyright{} 2013 Bastien Roucaries @email{roucaries.bastien+autoconf@@gmail.com}} @* @w{Copyright @copyright{} 2016 Felix Chern @email{idryman@@gmail.com}}

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2 of the License, or (at your
option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
Public License for more details.

You should have received a copy of the GNU General Public License along
with this program. If not, see <https://www.gnu.org/licenses/>.

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