DECISION METHOD FOR INCLUSIVE RELATION BETWEEN POINT AND CLOSED GRAPHIC

摘要

PURPOSE: To provide a decision method that can be used in a CAD/CAN system, etc., and capable of deciding inclusive relation between a supplied point and plural closed graphics. ;CONSTITUTION: A half line (c) is extended in an arbitrary direction setting the supplied point (b) as a start point on a plane provided with the plural closed graphics (a), and the intersection (d) of the half line (b) and each closed graphic (a) is found. Thence, the order of each intersection (d) by distance from the supplied point (b) is found, and it is decided whether the number of times of intersection of the closed graphic (a) including the intersection (d) and the half line (c) is the odd-number of times or even-number of times. Thence, a positive or negative decision value of same absolute value is supplied based on such decision whether it is the odd-number of times or even-number of times. The number of closed graphics including the supplied point can be found by adding the decision value of each intersection.;COPYRIGHT: (C)1993,JPO&Japio