Study On A Electronic Chart Service System Based On Mapserver

Web electronic chart can whenever and wherever possible characteristics of the Web browser based on very much in line with the characteristics of strong liquidity navigation management personnel, has management application in the shipping field in the rapidly growing popularity. Raster Web electronic chart service, can be in Web pages quickly in the form of pictures display chart, very good to meet the needs of the chart as background visually to ships and demand for other dynamic and static objects dynamic positioning and management of online ship monitoring applications, is the main form of Web electronic chart.Despite the high cost, but because of its powerful user-friendly editing, configuration and management interface and the navigation solution mapping function, the commercial software ArcGIS occupies a dominant position in the research and application of Web electronic chart area. This paper is based on the open source MapServer platform, its cross-platform, open characteristics and support for the S-57electronic chart data added function using, in-depth study of the key issues in the chart data access, cartography, chart service aims to develop a low cost, high performance, increase the diversity of Web electronic chart theory and technology on the one hand, on the other hand, hope to be able to provide application solutions of cheap, increase the optional user, so as to better promote the Web electronic chart application.To sum up, the main contents are as follows:(1) Electronic chart system architectureBased on the analysis of the characteristics of MapServer and its main components and function, design of the electronic chart system frame, software structure of MapServer and the main function module based on.(2) The expression of chart data organization and drawing based on MapFileResearch on MapServer access vector electronic chart data and efficiency through the MapFile configuration, to study how to refer to S-52and CJ-52standard, the various elements of the display using MapFile chart drawing, finally the main problems of the expression of MapFile chart data in organizing and existence, and the development of an automatically generated MapFile files.(3) To achieve Web chart and its optimization based on the tile cacheBased on the principle of interactive design, OpenLayers design and implementation using Web electronic chart service client architecture and electronic chart display, the basic operations (such as roaming, zooming, etc.) function. And the use of Ka-map and the realization of chart tile cache technology based on Pyramid model, in order to reduce the burden of server system, and improve the response speed of the client.