dnl check if the Windows WGL graphics library links
wgl_link_works=no
LIBWGL=""
if test "xbc_with_wgl" != "xno" ; then
    AC_CHECK_LIB(openglw32, glEnable, wgl_link_works=yes ; LIBWGL="-lopenglw32")
fi

dnl check if the SGI graphics library links
sgigl_link_works=no
LIBSGIGL=""
AC_CHECK_LIB(sgigl, getvideo, sgigl_link_works=yes ; LIBSGIGL="-lsgigl")