--- a/direction.h	Sat Jul 22 07:36:01 2006 +0000
+++ b/direction.h	Sat Jul 22 08:59:52 2006 +0000
@@ -98,6 +98,12 @@
 } Axis;
 
 
+static inline Axis OtherAxis(Axis a)
+{
+	return (Axis)(a ^ 1);
+}
+
+
 static inline Axis DiagDirToAxis(DiagDirection d)
 {
 	return (Axis)(d & 1);