Design And Realization Of Prototype System AutoGIS Based On Spatial Analysis Theory And Technology

A geographic information system (GIS) is a computer system for capturing, storing, managing, querying and analyzing data and associated attributes combined with computer graphics and database technology. Developing GIS with Visual C++ can solve the black box problem that professional GIS software faces. At the same time it is flexible, easy-expending and has its own copyright. Therefore, it has a satisfactory foreground for developing GIS aimed at information management, decision service and design.Most of traditional GIS systems developed with Visual C++ focus on drawing and compiling of maps and searching and managing of spatial data. But the core of GIS is spatial analysis which is the distinctiveness for GIS to ordinary information, CAD and electron map system. So the research in this paper provides some reference worthiness for spatial analysis development technology.This paper first studies three different types of spatial data model, and adopts a vector-based spatial analysis method by comparing their advantages and disadvantages. Then the paper studies spatial analysis theory especially on topological relation computing and spatial analysis methods, and presents a topological relation computing method of point, line and polygon by solving algebra equation. This method is easier to be realized than traditional topological relation algorithms such as point-set topological or Voronoi-based topological relation algorithm. Basing on the topological relation, this paper develops the corresponding algorithm for spatial query, overlay analysis and buffer analysis and further resolve the problems such as boundary superposition and hollow part in overlay analysis and so on.Based on the method mentioned above, a prototype GIS AutoGIS system has been realized with OOP technology under the Visual C++ platform. A figure drawing and compiling module is designed to draw points, lines and polygons by mouse or keyboard; A layer management module including establishment, sequencing, displaying and hiding of layer; Two-way search between figure object and its attribute is carried out. The spatial analysis, including topological analysis, overlay analysis, buffer analysis and so on, is achieved. The major GIS functions have been accomplished.