Research And Implementation Of Road Cartography Automatic Generalization Technology

With the development of computer related technology and their thorough application in cartography, the new technology and science are gradually born, such as digital cartography, geographic information system, etc. Digital cartography technology not only greatly improved the production efficiency of maps, but also paved the way for the research of digital maps’automatic generalization. Digital cartographic technique’s most obvious influence on cartography is having pushed the algorithm and modeling of cartography integration, the map database provides favorable conditions for the accuracy control of geographical spatial data and the quality control of cartography integration, the application of computer, mathematics, biotechnology and geology weakens the subjectivity of cartographic generalization’s process, promotes the development of map’s automatic generalization, improves the automatic process of cartographic generalization.The automatic generalization of linear features is a hot and key spot in the fields of cartographic generalization. As one of linear features in all features’map, road and other linear geographical features have something in common, but as the product of human production activities, road and linear natural geographical features have differences. This paper regards the road network on land as the research object, on the basis of exploring the principle of cartographic generalization and its status, features’ automatic generalization model and algorithm, designs a set of automatic generalization’s process and algorithm which can be used in road network features, and uses Visual Studio2008as the development platform, combining with SharpMap, ArcGIS Engine and DotNetBar, designs and realizes an automatic generalization system of plug-in road network.This paper includes parts. The first part is the introduction. It describes the research background, the basic contents of cartographic generalization, and the research status of automatic cartographic generalization under the environment of computer; The second part expounds some discipline theory bases, which are used in modern automatic cartographic generalization, including the application of genetic algorithm, graph theory, intelligence and the least square method in automatic cartographic generalization; The third part, regarding cartographic generalization theory as a foundation, focuses on the road features’generalization principles, the mathematical model of road features, the principle of road network’s selection and generalization, and describes the automatic simplified algorithm of road features commonly used; The fourth part aims at developing and achieving a plug-in road network’s automatic generalization system, deeply describes the host interfaces of plug-in road network’s automatic generalization system framework, the communication contract between plug-in and plug-in, between plug-in and host program, system framework’s host program, the dynamic analysis of plug-in and the whole development process of loading, and introduces the realization way of the basic function plug-ins and road features’automatic cartographic generalization functional plug-ins. At the end of this part, the paper gives processing results of the road network’s automatic generalization under the system; The last part summarizes the research, and points out the results of the study, the paper’s innovation and limits, and then makes a detailed analysis and prospect of further study.