fixed/improved finding and linking libgtk

CMakeLists.txt

@@ -497,11 +497,11 @@ ENDIF(MACOSX)
 IF(UNIX)
 IF(NOT BEOS)
 IF(NOT MACOSX)
-#FIND_PACKAGE(PkgConfig)
-#PKGCONFIG(libgtk-2.0 LIBGTK_INCLUDE_DIR LIBGTK_LINK_DIR LIBGTK_LINK_FLAGS LIBGTK_CFLAGS)
-# !!! FIXME
-SET(LIBGTK_LINK_FLAGS "-lgtk-x11-2.0")
-SET(LIBGTK_CFLAGS "-DPNG_NO_MMX_CODE -I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/include/atk-1.0 -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/cairo -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/freetype2 -I/usr/include/libpng12")
+FIND_PACKAGE(PkgConfig)
+pkg_check_modules (LIBGTK gtk+-2.0 )
+SET(LIBGTK_LINK_FLAGS "${LIBGTK_LDFLAGS}")
+SET(LIBGTK_CFLAGS "-DPNG_NO_MMX_CODE ${LIBGTK_CFLAGS}")
+
 IF(NOT LIBGTK_LINK_FLAGS)
     MESSAGE(STATUS "Can't find GTK+v2 headers/libraries. Can't build GTK+ GUI.")
 ELSE(NOT LIBGTK_LINK_FLAGS)