期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2002
卷号：XXXIV-5/W3
出版社：Copernicus Publications
摘要：As we know, today, GIS can't establish complex 3-dimensional landscape of city, the main reason is that GIS absent skillful modeling tools as these used in AutoCAD and 3Dmax. Although the main purpose of Virtual GIS is to establish beautiful and complex landscape, from the view of GIS, it's essential is Virtual Reality that using GIS data resource, it discard the majority of GIS features. In addition, many research works related to CAD model in 3-dimensional (3D) GIS also have been developed, but in these works, complex objects are still not taken into account seriously. AutoCAD and 3Dmax and et al software could establish beautiful habitation landscape, as we saw in many advertisements, however, GIS researchers usually consider situations much more about real geographical data and much more larger geographical areas. In 3-dimensional GIS, many objects in city environment are disposed in simple way, for example, buildings are considered as box, and many others constructions and plants are even not considered, the difficulty of the problem is that spatial relationships representation and the management of huge data that fetched from CAD models. However, 3D GIS can't avoid represent detailed landscape especially in city environment, on the other hand, many objects in real world is so special and so complex, it's difficult for any data model to represent it automatically, but CAD models which established mainly by alternate methods could be used to represent these objects very well, hence at the present time, construction of complex city landscape must ask for CAD models support, so we put forward one solution: Two types model should be used in 3-dimensional GIS: simple model and complex model, simple model could be automatically established, similar to many data models put forward by many 3D GIS research scholars; complex model is CAD model, its import from modeling tools, such as AutoCAD and 3Dmax et al, it's used as complement to simple model. All spatial calculation and disposal are based on simple model, complex model mainly used to give real landscape, while simple model and complex model could be used in mix way, such as LOD levels to accelerate visualization. In this paper, we mainly discuss construction methods of complex city landscape, including objects data modeling and data structure. At the end of the paper, one simple experiment is introduced.
关键词：3-dimensional GIS; CAD model; Complex city landscape; visualization
