【作者】 邢红生；

【导师】 马永强；

【作者基本信息】 西南交通大学 ， 计算机应用技术， 2004， 硕士

【摘要】 三维城市模型的构建与应用是目前国际GIS及相关科学研究的热点。特别是随着“数字地球”、“数字城市”等概念的提出，三维模型的构建方法显得越来越重要。传统的GIS是二维的，它将三维空间中的实体及其现象用二维空间的点、线、面来表示，这与人们的习惯思维方式不一致。因此符合人们习惯思维方式的、基于虚拟现实技术的三维GIS的研究已引起人们的普遍重视。 本文首先简要介绍了数字城市的基本概念、基本内容及关键技术。讨论了国内外3DGIS理论的研究状况，对已有的三维城市模型进行了分析比较，探讨了建筑物模型的数据获取、数据组织与管理以及模型构造方法，在此基础上，提出采用分层格网组合方法来实现规则建筑物的快速建模，并设计了一种基于关系数据库的、面向对象的数据管理模式来存储其数据的数据结构。在对建筑物封顶时，针对OpenGL不能直接填充凹多边形运用了一种直线剖分的方法来实现OpenGL对凹多边形的填充。 在建立了三维城市模型的基础上，本文对其进行可视化的方法进行了讨论。笔者采用Visual C++结合三维图形开发工具OpenGL，结合提出的模型，开发了一个初步的实验系统—虚拟城市建设系统，对采用该模型构建相对规则建筑物的可行性进行了论证。除此之外，在可视化的基础上实现了一些3DGIS的交互操作和空间分析，如：建筑物属性查询、建筑物按户查询、三维动态漫游等。 文章最后对全文内容进行了总结，并提出了值得进一步研究的问题。更多还原

【Abstract】 The constructions and applications of 3D City Model(3DCM) are presently the concemful subjects on the researches of GIS and its related fields.and they are becoming more and more significant for the bulid of "digital earth" and "Cyber city",the constructional method of 3DCM is becoming more and more important. Traditional GIS is a 2D system, It describes 3D objects and theirs phenomenon with points, lines and surfaces in 2D space, which are not accord with people’s traditional ideas. Therefore, much more attention were paid on 3DGIS which based on virtual reality technology.Firstly, the paper introduces the basic conception of the digital city, the basic contents and the key technology of the digital city.Secondly, the research status in domestic and overseas is analysed in this paper.The building model’s data acquisition,data organization,data management and the model construction method are also discussed in this paper. During the analysis and comparing of existing 3DCM, a divided-box 3D data model which can model a large proportion of simple buildings in urban is brought forward.Data stucture of the model is also put forward. On account of OpenGL can’t paint concave polygon, a new method named partition of beenline is brought forward.Based on the model,the author discussed how to realize the visualization of 3DCM. A testing application system named Vritual Reality City Simulation System is developed by the author using Visual C++ and 3D graphic tool OpenGL,which demonstrates the correctness of using this 3DCM to construct regular building.Meanwhile ,in 3D-scene,some functions of spatial analysis and interactive operations have been realized, such as spatial coordinate query, attribute query ,roaming,etc.Finally, the author make a conclusion of the whole thesis and some problems worthy of deeper study are put forward.更多还原