-PKG_CHECK_MODULES(GTK, gtk+-2.0 gtkglext-1.0)
-PKG_CHECK_MODULES(CURL, libcurl)
+PKG_CHECK_MODULES(GLIB, glib-2.0)
+PKG_CHECK_MODULES(GRITS, grits >= 0.6)
+
+# Check for gpsd support
+AC_ARG_ENABLE([gps], AS_HELP_STRING([--enable-gps], [Build with gpsd support]),
+ [PKG_CHECK_MODULES(GPSD, libgps >= 3.0)
+ AC_DEFINE([HAVE_GPSD], [], [Have GPSD support])
+ AC_SUBST(HAVE_GPSD, [TRUE])]
+)
+AM_CONDITIONAL([HAVE_GPSD], test "$HAVE_GPSD" = "TRUE")