1# -*- mode: autoconf -*-
2#
3# AX_CHECK_GL
4#
5# Check for an OpenGL implementation.  If GL is found, the required compiler
6# and linker flags are included in the output variables "GL_CFLAGS" and
7# "GL_LIBS", respectively.  If no usable GL implementation is found, "no_gl"
8# is set to "yes".
9#
10# If the header "GL/gl.h" is found, "HAVE_GL_GL_H" is defined.  If the header
11# "OpenGL/gl.h" is found, HAVE_OPENGL_GL_H is defined.  These preprocessor
12# definitions may not be mutually exclusive.
13#
14# version: 2.6
15# author: Braden McDaniel <braden@endoframe.com>
16#
17# This program is free software; you can redistribute it and/or modify
18# it under the terms of the GNU General Public License as published by
19# the Free Software Foundation; either version 2, or (at your option)
20# any later version.
21#
22# This program is distributed in the hope that it will be useful,
23# but WITHOUT ANY WARRANTY; without even the implied warranty of
24# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25# GNU General Public License for more details.
26#
27# You should have received a copy of the GNU General Public License
28# along with this program; if not, write to the Free Software
29# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
30# 02110-1301, USA.
31#
32# As a special exception, the you may copy, distribute and modify the
33# configure scripts that are the output of Autoconf when processing
34# the Macro.  You need not follow the terms of the GNU General Public
35# License when using or distributing such scripts.
36#
37AC_DEFUN([AX_CHECK_GL],
38[AC_REQUIRE([AC_CANONICAL_HOST])dnl
39AC_REQUIRE([AC_PATH_X])dnl
40AC_REQUIRE([AC_PROG_SED])dnl
41AC_REQUIRE([AX_PTHREAD])dnl
42
43AC_LANG_PUSH([C])
44AX_LANG_COMPILER_MS
45AS_IF([test X$ax_compiler_ms = Xno],
46      [GL_CFLAGS="${PTHREAD_CFLAGS}"; GL_LIBS="${PTHREAD_LIBS}"])
47
48#
49# Use x_includes and x_libraries if they have been set (presumably by
50# AC_PATH_X).
51#
52AS_IF([test X$no_x != Xyes -a -n "$x_includes"],
53      [GL_CFLAGS="-I$x_includes $GL_CFLAGS"])
54
55AC_CHECK_HEADERS([windows.h])
56
57ax_save_CPPFLAGS=$CPPFLAGS
58CPPFLAGS="$GL_CFLAGS $CPPFLAGS"
59AC_CHECK_HEADERS([GL/gl.h OpenGL/gl.h], , , [
60# if defined(HAVE_WINDOWS_H) && defined(_WIN32)
61#   include <windows.h>
62# endif
63])
64CPPFLAGS=$ax_save_CPPFLAGS
65
66m4_define([AX_CHECK_GL_PROGRAM],
67          [AC_LANG_PROGRAM([[
68# if defined(HAVE_WINDOWS_H) && defined(_WIN32)
69#   include <windows.h>
70# endif
71# ifdef HAVE_GL_GL_H
72#   include <GL/gl.h>
73# elif defined(HAVE_OPENGL_GL_H)
74#   include <OpenGL/gl.h>
75# else
76#   error no gl.h
77# endif]],
78                           [[glBegin(0)]])])
79
80m4_define([AX_CHECK_GL_GLX_PROGRAM],
81          [AC_LANG_PROGRAM([[
82# if defined(HAVE_WINDOWS_H) && defined(_WIN32)
83#   include <windows.h>
84# endif
85# ifdef HAVE_GL_GL_H
86#   include <GL/gl.h>
87# elif defined(HAVE_OPENGL_GL_H)
88#   include <OpenGL/gl.h>
89# else
90#   error no gl.h
91# endif]],
92                           [[glXQueryVersion(0, 0, 0)]])])
93
94AC_CACHE_CHECK([for OpenGL library], [ax_cv_check_gl_libgl],
95[ax_cv_check_gl_libgl=no
96case $host_cpu in
97  x86_64) ax_check_gl_libdir=lib64 ;;
98  *)      ax_check_gl_libdir=lib ;;
99esac
100ax_save_CPPFLAGS=$CPPFLAGS
101CPPFLAGS="$CPPFLAGS $GL_CFLAGS"
102AS_IF([test X$no_x != Xyes -a -n "$x_libraries"],
103      [LDFLAGS="$LDFLAGS -L$x_libraries"])
104ax_save_LDFLAGS=$LDFLAGS
105ax_save_LIBS=$LIBS
106ax_check_libs="-lopengl32 -lGL"
107for ax_lib in $ax_check_libs; do
108  AS_IF([test X$ax_compiler_ms = Xyes],
109        [ax_try_lib=`echo $ax_lib | $SED -e 's/^-l//' -e 's/$/.lib/'`],
110        [ax_try_lib=$ax_lib])
111  LDFLAGS="$ax_save_LDFLAGS $GL_LIBS"
112  LIBS="$ax_try_lib $ax_save_LIBS"
113AC_LINK_IFELSE([AX_CHECK_GL_PROGRAM],
114               [ax_cv_check_gl_libgl=$ax_try_lib; break],
115               [ax_check_gl_nvidia_flags="-L/usr/$ax_check_gl_libdir/nvidia"
116                LDFLAGS="$ax_save_LDFLAGS $GL_LIBS $ax_check_gl_nvidia_flags"
117                AC_LINK_IFELSE([AX_CHECK_GL_PROGRAM],
118                               [ax_cv_check_gl_libgl="$ax_check_gl_nvidia_flags $ax_try_lib"; break],
119                               [ax_check_gl_dylib_flag='-dylib_file /System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries/libGL.dylib:/System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries/libGL.dylib'
120                                LDFLAGS="$ax_save_LDFLAGS $GL_LIBS $ax_check_gl_dylib_flag"
121                                AC_LINK_IFELSE([AX_CHECK_GL_PROGRAM],
122                                               [ax_cv_check_gl_libgl="$ax_check_gl_dylib_flag $ax_try_lib"; break])])])
123done
124
125#
126# If no_x is "yes", we don't want to wind up using a libGL that is
127# linked with X11.  Test to see if the found libGL includes GLX
128# functions.  If it does and no_x is "yes", we want to reset
129# ax_cv_check_gl_libgl back to "no".
130#
131# Note that LDFLAGS and LIBS should still have whatever values they
132# had when we broke out of the test loop above; use that.
133#
134AS_IF([test "X$ax_cv_check_gl_libgl" != Xno],
135      [AC_LINK_IFELSE([AX_CHECK_GL_GLX_PROGRAM],
136                      [AS_IF([test X$no_x = Xyes],
137                             [ax_cv_check_gl_libgl=no])])])
138
139LIBS=$ax_save_LIBS
140AS_IF([test "X$ax_cv_check_gl_libgl" = Xno -a X$no_x = Xyes],
141      [LDFLAGS="$ax_save_LDFLAGS -framework OpenGL"
142      AC_LINK_IFELSE([AX_CHECK_GL_PROGRAM],
143                     [ax_cv_check_gl_libgl='-framework OpenGL'])])
144
145LDFLAGS=$ax_save_LDFLAGS
146CPPFLAGS=$ax_save_CPPFLAGS])
147
148AS_IF([test "X$ax_cv_check_gl_libgl" = Xno],
149      [no_gl=yes; GL_CFLAGS=""; GL_LIBS=""],
150      [GL_LIBS="$ax_cv_check_gl_libgl $GL_LIBS"])
151AC_LANG_POP([C])
152
153AC_SUBST([GL_CFLAGS])
154AC_SUBST([GL_LIBS])
155])dnl
156