John E Combs

US Patent:

49396617, Jul 3, 1990

Filed:

Sep 9, 1988

Appl. No.:

7/243317

Inventors:

Christopher Barker - New York NY
Christian Kunz - New York NY
John A. Combs - Babylon NY
John C. S. Park - New York NY

Assignee:

World Research Institute for Science and Technology - Long Island NY

International Classification:

G06F 1550

US Classification:

364443

Abstract:

Apparatus for a video navigation plotter with electronic charting, specifically such a plotter designed for marine use, and various methods for processing navigational data therein and displaying resulting navigational data thereon are disclosed herein. Specifically, this plotter stores coastline data only for those cells which contain coastline data within a given geographic region of a pre-defined chart. The data for each of these cells is stored in a unique data structure that stores data for a plurality of line segments that, when drawn, collectively depicts the geographic data stored within that cell. Each segment is stored in terms of coordinate locations for a starting point followed by coordinate offset values for each successive point in that cell. Only those cells and their constituent segments are drawn for coastline data that exists within a specific region to be displayed. Once a coastline chart is displayed, the inventive plotter permits navigational data to be overlaid thereon and through this capability provides several useful features as set forth herein.