【作者】 危拥军；

【导师】 王家耀；

【作者基本信息】 解放军信息工程大学 ， 地图制图学与地理信息工程， 2006， 博士

【摘要】 作为二维GIS发展到一定阶段的必然产物，三维GIS可形象直观地反映研究区域的地形、地貌和地物等多种相关信息。目前，国内外诸多学者对三维GIS的数据模型、可视化表现以及单一领域的应用提出了许多方法和技术手段。但三维GIS的研究与实现仍处于初步阶段，所实现的部分三维GIS功能也只是出现在一些实验性原型系统中。本文的工作主要包括以下几个方面： (1) 阐述了三维GIS的基本概念，提出三维GIS的本质特征在于三维对象的空间坐标由(X、Y、Z)来表示。论述了三维GIS研究的目的和意义，阐述了三维GIS与虚拟现实、仿真的关系。介绍了国内外主要的三维可视化软件成果，分析了三维GIS的研究现状和基本要求，总结了当前三维GIS研究与实现中存在的问题，提出了对三维GIS发展的思考。 (2) 介绍了三维实体的表示及其数据模型的研究成果。提出了三维实体的组织形式一三维形体的概念。提出基于面的数据组织方式是三维GIS空间实体数据模型选择的主要依据，三维形体的数据组织以表面表示模型为主，形体数据嵌入到GIS矢量结构中。在介绍了空间数据模型特点与分类基础上，总结了三维GIS的数据内容与数据库管理模式，提出并阐述了三维GIS的基本元素——三维空间对象分类。 (3) 提出了基于表面表示的三维空间矢量数据模型——SRSD。这种三维矢量数据模型由面向对象的二维GIS发展而来，符合人们处理GIS基本元素对象的习惯，GIS系统由二维向三维的过渡也较易实现。在3DGIS原型系统实践中，设计并实现了三维矢量数据结构和三维形体数据结构，该数据结构既可以保证地物数据与地形数据相互关联，又可以单独应用，支持在普通PC机上的大范围海量数据漫游。 (4) 介绍了海量数据的组织方式，论述了基于线程的多任务并发处理技术和基于数据分页的动态装载调度技术。提出了基于海量数据显示的数据调度时间指标。研究了三维空间对象数据的组织原则和方式，在三维矢量数据的组织上，提出了分层设置LOD级进行管理的设想。 (5) 在分析三维地理信息符号的国内外现状基础之上，研究了三维地理信息传输模式。分析了三维地理信息符号的特点，阐述了三维符号模型的基本概念，提出了三维符号分类设计原则及构图规律，研究了三维地理信息符号的视觉变量，为三维符号库的建立和应用奠定了理论基础。综合运用边界模型(BR)、参数模型等结构来表示三维符号的空间数据，解决了三维符号形体信息的结构设计问题。 (6) 介绍了三维地理信息系统3DGIS的体系结构设计。介绍并实施了系统开发设更多还原

【Abstract】 As the inevitable result of the 2D GIS that develops to a certain technical stage, the 3D GIS can directly reflect many kinds of relative information of geographical area, such as terrain, relief, ground feature and so on. At present, many scholars bring forward some methods and technical means to the data model, visual representation and applications in a single field of 3D GIS. But the research and implementation of 3D GIS are still in the primary stage. Some parts of 3D GIS functions implemented only in experimental prototype systems. The research in this dissertation mainly includes following several aspects:(1)It describes the basic concept of 3D GIS and brings forward the essence of 3D GIS, namely, the space coordinate of 3D object is represented by (X, Y, Z). It discusses the aim and significance of the research on 3D GIS, and describes the relations among the 3D GIS, VR and simulation. This dissertation also introduces the mainstream 3D visualization software home and abroad, and analyzes the research status quo and basic requirements of 3D GIS. Issues in the present research and implementation are summarized and the thought to the development of 3D GIS is brought forward.(2) The research result on 3D data model of 3D entity representation is introduced, and The concept of the organization form of 3D entity if brought forward, namely 3D Shape Entity (SE). It considers that the basic selection foundation of 3D GIS spatial entity data model is the data organization mode base on surface. The data structure of 3D SE is mainly Surface Representation method and the data of SE is embedded into the GIS vector structure. Base on the characteristics and classification of spatial data model, the data contents and database management mode of 3D GIS is summarized, and the classification of 3D spatial object, which is the basis element of 3D GIS is brought forward and described.(3)It brings forward the 3D spatial vector data model based on Surface Representation (SR3D). This kind of 3D vector data model develops from the object-oriented 2D GIS and accords with the custom of processing the GIS element. So it is easy to implement the transition from 2D to 3D. In the practice of 3D GIS prototype system, the 3D vector data structure and 3D SE data structure are designed and realized. The data structures not only can guarantee the correlation between the ground feature data and terrain data but also can be applied alone to support the mass data roam of large region on PC.(4)It introduces the organization mode of mass data and describes the multi-task subsequent process technique based on thread and the data management technique based on dynamic load of data page. It also presents the time index of data management in the mass data demonstration. The organization principle and way of the 3D spatial object data and is studied, and the management assumption to organize the 3D vector data in the form of different layer with different LoD Grades is brought forward.更多还原