+
+ x = size
+ y = 0
+ angle = 0
+ self.next_pos(x, y, angle)
+ angle = direction*90*pi/180
+ self.next_pos(x, y, angle)
+
+ y = size*direction
+ self.next_pos(x, y, angle)
+ angle = direction*180*pi/180
+ self.next_pos(x, y, direction*-180*pi/180)
+
+ x = 0
+ self.next_pos(x, y, angle)
+ angle = direction*270*pi/180
+ self.next_pos(x, y, angle)
+
+ y = 0
+ self.next_pos(x, y, angle)
+ angle = 0
+ self.next_pos(x, y, angle)
+