-# libpng
-PKG_CHECK(libpng, yes, [PNG], [libpng-config], [png.h], png,
- png_create_write_struct, libpng, [http://www.libpng.org/])
-AC_SUBST(PNG_CFLAGS)
-AC_SUBST(PNG_LIBS)
+AS_CASE([$enable_lbxgui],
+ [no], [have_gtk=false],
+ [yes], [DX_CHECK_GTK2([2.16], [have_gtk=true])],
+ [DX_CHECK_GTK2([2.16], [have_gtk=true], [have_gtk=false])])