Fig. 6.

Illustration of the standardized angle. C1 is a cancelled target, C2a-c are potential consecutive cancellations. The standardized angle is 1 for vertical (between C1 and C2a) or horizontal (between C1 and C2c) inter-cancellation angles, and approaches 0 for diagonal angles (between C1 and C2b). Paths containing predominantly horizontal and vertical lines are considered to be more efficient, therefore a high standardized angle is an indication of an efficient search pattern