Updated versions of AX_CHECK_GL*

[Braden McDaniel]

Attached are updated versions of my OpenGL macros, AX_CHECK_GL,
AX_CHECK_GLU, and AX_CHECK_GLUT. Operation with the Microsoft C/C++
compiler has been improved. Also included is a macro that checks for
that compiler (which AX_CHECK_GL* now depend on), the form of which was
cribbed from _AC_LANG_COMPILER_GNU in the autoconf implementation.

-- 
Braden McDaniel                           e-mail: <address@hidden>
<http://endoframe.com>                    Jabber: <address@hidden>

dnl @synopsis AX_CHECK_GL
dnl
dnl Check for an OpenGL implementation.  If GL is found, the required compiler
dnl and linker flags are included in the output variables "GL_CFLAGS" and
dnl "GL_LIBS", respectively.  This macro adds the configure option
dnl "--with-apple-opengl-framework", which users can use to indicate that
dnl Apple's OpenGL framework should be used on Mac OS X.  If Apple's OpenGL
dnl framework is used, the symbol "HAVE_APPLE_OPENGL_FRAMEWORK" is defined.  If
dnl no GL implementation is found, "no_gl" is set to "yes".
dnl
dnl @version 1.7
dnl @author Braden McDaniel <address@hidden>
dnl
AC_DEFUN([AX_CHECK_GL],
[AC_REQUIRE([AC_PATH_X])dnl
AC_REQUIRE([ACX_PTHREAD])dnl

#
# There isn't a reliable way to know we should use the Apple OpenGL framework
# without a configure option.  A Mac OS X user may have installed an
# alternative GL implementation (e.g., Mesa), which may or may not depend on X.
#
AC_ARG_WITH([apple-opengl-framework],
            [AC_HELP_STRING([--with-apple-opengl-framework],
                            [use Apple OpenGL framework (Mac OS X only)])])
if test "X$with_apple_opengl_framework" = "Xyes"; then
  AC_DEFINE([HAVE_APPLE_OPENGL_FRAMEWORK], [1],
            [Use the Apple OpenGL framework.])
  GL_LIBS="-framework OpenGL"
else
  AX_LANG_COMPILER_MS
  if test X$ax_compiler_ms = Xyes; then
    GL_CFLAGS="${PTHREAD_CFLAGS}"
    GL_LIBS="${PTHREAD_LIBS} -lm"
  fi

  #
  # Use x_includes and x_libraries if they have been set (presumably by
  # AC_PATH_X).
  #
  if test "X$no_x" != "Xyes"; then
    if test -n "$x_includes"; then
      GL_CFLAGS="-I${x_includes} ${GL_CFLAGS}"
    fi
    if test -n "$x_libraries"; then
      GL_LIBS="-L${x_libraries} -lX11 ${GL_LIBS}"
    fi
  fi

  AC_LANG_PUSH(C)

  AC_CHECK_HEADERS([windows.h])

  AC_CACHE_CHECK([for OpenGL library], [ax_cv_check_gl_libgl],
  [ax_cv_check_gl_libgl="no"
  ax_save_CPPFLAGS="${CPPFLAGS}"
  CPPFLAGS="${GL_CFLAGS} ${CPPFLAGS}"
  ax_save_LIBS="${LIBS}"
  LIBS=""
  ax_check_libs="-lopengl32 -lGL"
  for ax_lib in ${ax_check_libs}; do
    if test X$ax_compiler_ms = Xyes; then
      ax_try_lib=`echo $ax_lib | sed -e 's/^-l//' -e 's/$/.lib/'`
    else
      ax_try_lib="${ax_lib}"
    fi
    LIBS="${ax_try_lib} ${GL_LIBS} ${ax_save_LIBS}"
    AC_LINK_IFELSE(
    [AC_LANG_PROGRAM([[
# if HAVE_WINDOWS_H && defined(_WIN32)
#   include <windows.h>
# endif
# include <GL/gl.h>]],
                     [[glBegin(0)]])],
    [ax_cv_check_gl_libgl="${ax_try_lib}"; break])
  done
  LIBS=${ax_save_LIBS}
  CPPFLAGS=${ax_save_CPPFLAGS}])

  if test "X${ax_cv_check_gl_libgl}" = "Xno"; then
    no_gl="yes"
    GL_CFLAGS=""
    GL_LIBS=""
  else
    GL_LIBS="${ax_cv_check_gl_libgl} ${GL_LIBS}"
  fi
  AC_LANG_POP(C)
fi

AC_SUBST([GL_CFLAGS])
AC_SUBST([GL_LIBS])
])dnl

dnl @synopsis AX_CHECK_GLU
dnl
dnl Check for GLU.  If GLU is found, the required preprocessor and linker flags
dnl are included in the output variables "GLU_CFLAGS" and "GLU_LIBS",
dnl respectively.  This macro adds the configure option
dnl "--with-apple-opengl-framework", which users can use to indicate that
dnl Apple's OpenGL framework should be used on Mac OS X.  If Apple's OpenGL
dnl framework is used, the symbol "HAVE_APPLE_OPENGL_FRAMEWORK" is defined.  If
dnl no GLU implementation is found, "no_glu" is set to "yes".
dnl
dnl @version 1.2
dnl @author Braden McDaniel <address@hidden>
dnl
AC_DEFUN([AX_CHECK_GLU],
[AC_REQUIRE([AX_CHECK_GL])dnl
AC_REQUIRE([AC_PROG_CXX])dnl
GLU_CFLAGS="${GL_CFLAGS}"
if test "X${with_apple_opengl_framework}" != "Xyes"; then
  AC_CACHE_CHECK([for OpenGL Utility library], [ax_cv_check_glu_libglu],
  [ax_cv_check_glu_libglu="no"
  ax_save_CPPFLAGS="${CPPFLAGS}"
  CPPFLAGS="${GL_CFLAGS} ${CPPFLAGS}"
  ax_save_LIBS="${LIBS}"
  LIBS=""
  ax_check_libs="-lglu32 -lGLU"
  for ax_lib in ${ax_check_libs}; do
    if test X$ax_compiler_ms = Xyes; then
      ax_try_lib=`echo $ax_lib | sed -e 's/^-l//' -e 's/$/.lib/'`
    else
      ax_try_lib="${ax_lib}"
    fi
    LIBS="${ax_try_lib} ${GL_LIBS} ${ax_save_LIBS}"
    #
    # libGLU typically links with libstdc++ on POSIX platforms. However,
    # setting the language to C++ means that test program source is named
    # "conftest.cc"; and Microsoft cl doesn't know what to do with such a
    # file.
    #
    AC_LANG_PUSH([C++])
    if test X$ax_compiler_ms = Xyes; then
      AC_LANG_PUSH([C])
    fi
    AC_LINK_IFELSE(
    [AC_LANG_PROGRAM([[
# if HAVE_WINDOWS_H && defined(_WIN32)
#   include <windows.h>
# endif
# include <GL/glu.h>]],
                     [[gluBeginCurve(0)]])],
    [ax_cv_check_glu_libglu="${ax_try_lib}"; break])
    if test X$ax_compiler_ms = Xyes; then
      AC_LANG_POP([C])
    fi
    AC_LANG_POP([C++])
  done
  LIBS=${ax_save_LIBS}
  CPPFLAGS=${ax_save_CPPFLAGS}])
  if test "X${ax_cv_check_glu_libglu}" = "Xno"; then
    no_glu="yes"
    GLU_CFLAGS=""
    GLU_LIBS=""
  else
    GLU_LIBS="${ax_cv_check_glu_libglu} ${GL_LIBS}"
  fi
fi
AC_SUBST([GLU_CFLAGS])
AC_SUBST([GLU_LIBS])
])

dnl @synopsis AX_CHECK_GLUT
dnl
dnl Check for GLUT.  If GLUT is found, the required compiler and linker flags
dnl are included in the output variables "GLUT_CFLAGS" and "GLUT_LIBS",
dnl respectively. This macro adds the configure option
dnl "--with-apple-opengl-framework", which users can use to indicate that
dnl Apple's OpenGL framework should be used on Mac OS X. If Apple's OpenGL
dnl framework is used, the symbol "HAVE_APPLE_OPENGL_FRAMEWORK" is defined.  If
dnl GLUT is not found, "no_glut" is set to "yes".
dnl
dnl @version 1.8
dnl @author Braden McDaniel <address@hidden>
dnl
AC_DEFUN([AX_CHECK_GLUT],
[AC_REQUIRE([AX_CHECK_GLU])dnl
AC_REQUIRE([AC_PATH_XTRA])dnl

if test "X$with_apple_opengl_framework" = "Xyes"; then
  GLUT_CFLAGS="${GLU_CFLAGS}"
  GLUT_LIBS="-framework GLUT -lobjc ${GL_LIBS}"
else
  GLUT_CFLAGS=${GLU_CFLAGS}
  GLUT_LIBS=${GLU_LIBS}

  #
  # If X is present, assume GLUT depends on it.
  #
  if test "X${no_x}" != "Xyes"; then
    GLUT_LIBS="${X_PRE_LIBS} -lXmu -lXi ${X_EXTRA_LIBS} ${GLUT_LIBS}"
  fi

  AC_LANG_PUSH(C)

  ax_save_CPPFLAGS="${CPPFLAGS}"
  CPPFLAGS="${GLUT_CFLAGS} ${CPPFLAGS}"

  AC_CACHE_CHECK([for GLUT library], [ax_cv_check_glut_libglut],
  [ax_cv_check_glut_libglut="no"
  ax_save_LIBS="${LIBS}"
  LIBS=""
  ax_check_libs="-lglut32 -lglut"
  for ax_lib in ${ax_check_libs}; do
    if test X$ax_compiler_ms = Xyes; then
      ax_try_lib=`echo $ax_lib | sed -e 's/^-l//' -e 's/$/.lib/'`
    else
      ax_try_lib="${ax_lib}"
    fi
    LIBS="${ax_try_lib} ${GLUT_LIBS} ${ax_save_LIBS}"
    AC_LINK_IFELSE(
    [AC_LANG_PROGRAM([[
# if HAVE_WINDOWS_H && defined(_WIN32)
#   include <windows.h>
# endif
# include <GL/glut.h>]],
                     [[glutMainLoop()]])],
    [ax_cv_check_glut_libglut="${ax_try_lib}"; break])

  done
  LIBS=${ax_save_LIBS}
  ])
  CPPFLAGS="${ax_save_CPPFLAGS}"
  AC_LANG_POP(C)

  if test "X${ax_cv_check_glut_libglut}" = "Xno"; then
    no_glut="yes"
    GLUT_CFLAGS=""
    GLUT_LIBS=""
  else
    GLUT_LIBS="${ax_cv_check_glut_libglut} ${GLUT_LIBS}"
  fi
fi

AC_SUBST([GLUT_CFLAGS])
AC_SUBST([GLUT_LIBS])
])dnl

dnl @synopsis AX_LANG_COMPILER_MS
dnl
dnl Check whether the compiler for the current language is Microsoft.
dnl
dnl This macro is modeled after _AC_LANG_COMPILER_GNU in the GNU Autoconf
dnl implementation.
dnl
dnl @version 1.0
dnl @author Braden McDaniel <address@hidden>
dnl
AC_DEFUN([AX_LANG_COMPILER_MS],
[AC_CACHE_CHECK([whether we are using the Microsoft _AC_LANG compiler],
                [ax_cv_[]_AC_LANG_ABBREV[]_compiler_ms],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[#ifndef _MSC_VER
       choke me
#endif
]])],
                   [ax_compiler_ms=yes],
                   [ax_compiler_ms=no])
ax_cv_[]_AC_LANG_ABBREV[]_compiler_ms=$ax_compiler_ms
])])