APPARATUS FOR CALCULATING REPRESENTATIVE POINT OF PATTERN ELEMENT OF NATURAL AND ARTIFICIAL OBJECTS FOR DIGITAL SPATIAL DATA

摘要

PROBLEM TO BE SOLVED: To properly find a representative point of a pattern element (line and plane) showing the shapes and attributes of a fundamental natural and artificial objects in digital spatial data such as a map.;SOLUTION: The center point (Xmid, Ymid) of the maximum circumscribed rectangle is found in the pattern element. The point is determined as the representative point when the point is located within the pattern element (Fig. 3A), and an intersection point (Xc, Yc), with the pattern element, of a straight line 21 in the shortest distance from the center point to a line segment of the pattern element, and an intersection point (Xb, Yb) of a prolonged line of the straight line 21 with the pattern element are found and the middle point (Xm, Ym) between the intersection points (Xc, Yc), (Xb, Yb) is determined as the representative point when the center point is located outside the pattern element, as shown in Fig. 3B.;COPYRIGHT: (C)2002,JPO