METHODS OF PARTITIONING A REGION REPRESENTED BY CONTOURS INTO SMALLER POLYGONAL ZONES AND CALCULATING DATA FOR DIGITAL ELEVATION MODEL AND DATA FOR CONSTRUCTING GEOGRAPHICAL SURFACES OF THE REGION, AND A RECORDING MEDIUM IN WHICH PROGRAMS FOR IMPLEMENTING THE METHODS ARE RECORDED

摘要

A method for calculating DEM(Digital Elevation Model) data and topographical surface configuration data and a recording medium in which a program for executing the method is recorded are provided to generate DEM data to which the actual topographical features of a corresponding area are reflected from a given contour line set. A contour line tree for expressing the correspondence between contour lines is prepared from data about a contour line set(S10,S12). By using the contour line tree, all sub-domains which are areas between adjacent contour lines are calculated(S14). The intermediate axis of each sub-domain is calculated(S18). Each sub-domain is divided by all segments of the intermediate axis. The segments of the intermediate axis belong to a set of all center points of the maximum circles.