The Research And Realization Of 3D Terrain Visualization Methods Based On ArcGIS

With the continuing development of the application of GIS, the former methods which deal with three-dimensional terrain 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 dynamically interactive three dimensional(3D) visualization. At the same time, with the development of computer graphics technology, 3D simulation gradually improves, 3D figure of terrain has more advantages than plane map. Manifested the 3D terrain tendencyThis paper analyses the building technology of 3D terrain and visualization at home and abroad nowadays. Integrated with the latest development of 3D terrain, such as ComGIS based on real data and component technology, this paper implements the 3D terrain building based on vision sense using component. This paper summarize the fundamental theory and method of DTM and DEM modelling, including Regular Square Grid(RSG) and Triangulated Irregular Network(TIN).Then, the basic principles of drawing 3D graph by computer are discussed, particularly explained the fundamental theory of coordinate transform, projection transform and light model.This paper uses ArcObjects component storehouse which is provided by ESRI Company, union VisualC++6.0 ,ArcGis8.3 development environment, develops a system which has the three-dimensional display DEM terrain surface,superimposes image data and three dimensional scene roam functions. This system may be useful to the management of community, the urban planning and forest fire protection ,the idea used in the system may be useful for the developer who are on the way to secondary develop 3DGIS system by components.