Development And Application Of 3D GIS System Based On ArcGIS Engine

The 3D GIS is one of the newest trends of the development of GIS science. Different from 2D GIS, 3D GIS provides human being more realistic feeling about the representation of natural world. It demonstrates various phenomena of geographic space with three-dimensional formation technology. Not only the horizontal relationships of spatial objects are represented, but also the vertical relationships of them are described and represented. Moreover, it is a unique function of 3D GIS to analyze and operate on spatial objects under a three-dimensional environment.This thesis summarized the disadvantages of lacking vivid representation of geographic models at current 3D GIS platforms, as well as lacking spatial analyzing ability in current scientific visualization software. A new theory was advocated to combine GIS platform and visualization software, in other word, using the model generating function of 3D modeling software and the GIS analysis function of GIS software to develop 3D GIS application system. As a result, a 3D GIS system of the campus of ECNU is established based on the combination of Multigen Creator and ArcGIS Engine Platform.This thesis consists of 6 chapters. Chapter one is the introduction to the definition, features and functions of 3D GIS. It also summarized the current research progress and future trends of both national and international wide 3D GIS research field. Meanwhile the research target and main research content were brought forward based on the above background. Chapter two gives the theory of 3D data models and the methods of their transformations. A further exploration explains the structure and features of OpenFlight format in 3D data model Multipatch and Multigen within ArcGIS. Moreover, based on ArcObjects, it successfully input OpenFilght model into the Multipatch FeatureClass of Shapefile. Chapter three illustrated the modelling methods, which are the geo-reference, texture mapping and multiple objects, to build the campus model of ECNU using Creator software. Chapter four listed the procedures of the system development design, including the system general design, system data layer design, as well as the development of system functional modules. The attribute data and spatial data are stored in a distributed way. The encapsulation of data entities isolates the operation layer and data layer, which makes the data layer absolutely transparent to developers. The development of functional modules consists of eight sub modules, which are data access module, 3D browser, feature selection, attributes query, interactive measurement, interesting point positioning, 3D modelinput and animation generation. Chapter five provides an example of system application. Chapter six summarizes the revolutions and shortages of this paper and gives the possible perspectives of future researches.There are two innovative aspects of the research: First, the new way ofcombining GIS platform and visualization software to develop a 3D GIS system resolves that 3D models just can be displayed but be queried in the former 3D GIS system; Second, the attribute data and spatial data are stored in a distributed way. As a result, different developments can share the attribute data not using GIS software.