现有的3D-GIS空间数据结构在构建地下数据及地上－地表－地下三维空间对象一体化表达方面存在不足。本研究扩展了传统GIS三维空间数据结构,提出了地上－地表－地下三维空间对象一体化表达模型,并在关键技术研究基础上,用C# + OpenGL实现了模型可视化,并实现了地上－地表－地下三维空间对象浏览、查询、剖面分析等功能。此研究成果应用到了三峡库区高切坡监测预警信息系统中,突破了传统三维空间可视化表达和空间数据结构的局限,具有重要的理论和实践意义。

Three-dimensional GIS is more and more extensively used in the modeling and analyzing of geological bodies. It has the advantages of intuition, real and powerful analysis functions. The High-Cutting Slope is a special kind of geological body, which has its own characteristics and is necessary to be modeled in an integrated way. It is appropriate and efficient to develop a visualized and aided analysis system of the high-cutting slopes using the 3D GIS. By studying the 3D visualized modeling algorithms, we noticed that there isn’t an algorithm which can effectively model underground objects, ground objects and ground surface from the same viewport and at the same time, but it is needed in the modeling of the high-cutting slopes because of their characteristics and potential hazards. As a result of this, we proposed a new concept of underground ground surface-ground objects integrated visualization which points out the way to solve the problem of integrated model. Based on this new concept, we extended the data structure and modeling algorithm of 3D GIS, and implemented some relative functions such as: three-dimensional navigation, format converting from common GIS data formats, visualization of the integrated models and so on by using OpenGL and C#. We also implemented some spatial analysis functions such as spatial query and spatial plane slice based on the new data structure, and developed an information system which is currently used in the monitoring and early-warning information system for the high-cutting slopes in the Three Gorges Area.