--- a/src/mb_types.h	Mon Aug 04 10:10:47 2008 +0800
+++ b/src/mb_types.h	Mon Aug 04 20:08:37 2008 +0800
@@ -50,6 +50,10 @@
 			     int *n_overlays, geo_t **overlays);
 #define geo_get_shape(g) ((g)->shape)
 #define geo_set_shape(g, sh) do {(g)->shape = sh;} while(0)
+#define _geo_is_in(a, s, w) ((a) >= (s) && (a) < ((s) + (w)))
+#define geo_pos_is_in(g, _x, _y)				\
+    (_geo_is_in(_x, (g)->cur_area.x, (g)->cur_area.w) &&	\
+     _geo_is_in(_y, (g)->cur_area.y, (g)->cur_area.h))
 
 
 /*! \brief A coordination system.