| By the digital form , GIS(Geographical Information System) describe current state and varieties of the earth people live in. The mode is expressed by spatial data and attribute data that exhibit spatial attribute. The system include lots of function: inputing/outputing ,storage, displaying of spatial data and query, compositive analysing , assistant decision-making of geographical information.With appearance of the concept "digital earth",it is feasible and obligatory to construct huge , visual, digital information system,which is based on data visualization.With the continuting development of the application of GIS, the former methods which deal with three-dimensional data in 2D manner, couldn't meet the needs of practical applications any longer. Users want to process, analyze and display the geographic information in manner of dynamicially interactive three-dimensional visualization. At the same time, with the maturing of 2D data model and data structure techniques, the development of graphics theory and databases techniques, etc. it is possible for prosperous development of three-dimensional GIS.The paper attempts to find a method to achieve of Visualization of the Terrain and surface features, give up the "object- texture" model,the memory model and configuration of kinds of data,and achieve the interactive query technique of spatial data and attribute data and spatial analyzing technique.Based on lots of advanced results of computer graphics, modern mathematics, computer science and topography, etc. this thesis discussed the technique and theory of clipping three-dimensional. The content mostly include: terrain modeling techniques for digital elevation model, surface features modeling technique, the displaying method of the connect of terrain and surface features, OpenGL graphics interface technique and graphics protract technique, the three-dimensional choice technique , the interactive query technique of spatial data and attribute data and spatial analyzing technique.
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