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In the era of information explosion, with the quickening pace of modern life, mobile electronic devices which could provide a variety of information such as mobile phones become more and more indispensable to people in their life and work. At the same time, geospatial information is more widely in all walks of life, the embedded GIS that running on the mobile devices is closely related to people’s lives and is liked by more and more people. As a various of types of mobile devices available and difference between the embedded platforms, one based on embedded platforms, efficient, portable GIS map engine is proposed, also explained the function of each module in the engine, and some key technologies involved in the research as following: organization and management of the data, optimization of the map displaying, efficient spatial index.For the requirement of embedded GIS map data, including wide coverage of map data, complete geographic elements, complete feature attribute information, high accuracy of the map data, the topological relations between the elements must be correct, the occupation of storage space by map data should be as small as possible because of the restriction of embedded hardware equipment, for the effective management and use of the map data, a file system is designed. To speed up the displaying of map in embedded device, a variety of optimization methods, such as the application of LOD, data pre-fetching and so on.In this paper, to facilitate the migration to a variety of platforms especially in the embedded devices, map engine is based on the platform of winXP and winCE, developed by C++; It is away from reliance on the use of the database by using of file system to provide map-data; Using the map engine designed by this paper, the speed of map display is fast so that the user dose not feel a noticeable delay, the performance of map is beautiful and plump. As a result of those, the needs of customer is better met.
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