AC_DEFUN(AC_FIND_PNG,
[
AC_REQUIRE([AC_FIND_ZLIB])
AC_REQUIRE([KDE_CHECK_EXTRA_LIBS])
AC_MSG_CHECKING([for libpng])
AC_CACHE_VAL(ac_cv_lib_png,
[
kde_save_LIBS="$LIBS"
LIBS="$LIBS $all_libraries -lpng $LIBZ -lm -lX11 $LIBSOCKET"
kde_save_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS $all_includes"
AC_LANG_C
AC_TRY_LINK(dnl
    [
    #include<png.h>
    ],
    [
    png_structp png_ptr = png_create_read_struct(  /* image ptr */
		PNG_LIBPNG_VER_STRING, 0, 0, 0 );
    return( png_ptr != 0 );
    ],
    eval "ac_cv_lib_png='-lpng $LIBZ -lm'",
    eval "ac_cv_lib_png=no"
)
LIBS="$kde_save_LIBS"
CFLAGS="$kde_save_CFLAGS"
])dnl
if eval "test ! \"`echo $ac_cv_lib_png`\" = no"; then
  AC_DEFINE_UNQUOTED(HAVE_LIBPNG, 1, [Define if you have libpng])
  LIBPNG="$ac_cv_lib_png"
  AC_SUBST(LIBPNG)
  AC_MSG_RESULT($ac_cv_lib_png)
else
  AC_MSG_RESULT(no)
  LIBPNG=""
  AC_SUBST(LIBPNG)
fi
])