Arcobjects-based Landscape Visualization

For the existing GIS's limitation, which only used to describe the two dimensions information in our lives. In fact, there is many information in our lives which used to us is missing in the two dimensions GIS. As the result, the theme about three dimensions geographic information system has been popular since 1980s. As a system which to studies the three dimensions space, the 3DGIS must has functions to deal with many information about space, such as modeling, describing, management, operation, analysis, making decision and so on. What we should do in the experience of research are not only to extend the function of 2DGIS, but also to study such as the models of analysis, the methods of managing the data, the technic of visualization of the 3D data and so on.In this paper the author discussed the topic of visualization and query of 3DGIS by three steps. At the first step, the author summarized the progress of research on the 3DGIS and the methods of developing a new GIS based on the old GIS software. At the second step, taking the limitation of some technic of visualization of the 3Dscene into account, the author selected the ArcObjects the components are provided by ESRI to extend the old 3DGIS software. At this step, the methods, technic and processes were described in the paper. The author developed the system in the Visual Basic 6.0 or VBA environment, and made the visualization of 3Dscence, the flying in the scene and some query realized. The 3Dscene about an area was realized by the technic and processes which were described at the second step. At the third step, the simply queries about terrain and objects were realized. The queries about terrain were based on DEM, but the queries objects were realized by ADO. In this process all the data in the 3Dscence was stored in Geodatabase by a special way.This GIS system may be useful to the management of community and the urban planning, the idea used in the system may be useful for the developer who are on the way to develop a new 3Dscene by components.