地理信息系统三维建模及可视化技术研究

【作者】 戴红毅；

【导师】 张修如；

【作者基本信息】 中南大学 ， 计算机应用技术， 2004， 硕士

【摘要】 长期以来，地理信息系统(GIS)都是局限于二维表达，二维GIS存在着自身难以克服的缺陷，它只能处理平面X、Y轴上的信息，不能处理Z轴方向上的信息。二维GIS本质上是基于抽象符号的系统，不能给人以自然界的真实感受。随着应用的深入，迫切要求三维GIS。与二维GIS相比，三维GIS对客观世界的表达能给人以更真实的感受，它以立体造型技术给用户展现地理空间现象。因此，对地理信息三维可视化系统的研究具有很高的研究价值。 论文就地理信息三维可视化系统的三维建模、空间分析和可视化等相关内容进行了研究。三维建模就是通过大量的离散数据点构造三维立体表面，并采用一定的数据结构保存数据点信息和点与点之间的关系。论文研究了离散点构造不规则三角网的过程，并对经典的构造Delaunay三角网算法进行了改进，改进后的算法具有较好的运行效果。为了实现三维场景的实时显示，论文重点分析了复杂地形模型的简化和多分辨率表示，并提出了一种视相关动态多分辨率地形模型及其相关算法。空间分析是地理信息系统的的主要特征，也是评价一个地理信息系统功能的主要指标之一，就此论文进行了基本地形因子分析、可视性分析、等高线分析和洪水淹没分析。论文最后讨论了空间数据可视化的过程，研究了消隐、光照、纹理映射和动画等技术，从而生成三维真实感图形。三维空间数据可视化能为管理和决策提供更加直接和真实的目标和研究对象。论文所做的研究工作对地理信息三维可视化系统的实现有一定的价值。更多还原

【Abstract】 Geographic Information System (GIS) has constrained to the two-dimension for a long time. The two-dimension GIS has its own fault which is hard to overcome. That is, it can only manager the information over the plane constructed by X-Y axes but the Z axes. It is in essence a system based on the abstract symbol, so it can’t show the actual feeling of nature.With the development of GIS application, the people demand the three-dimension GIS urgently. Compared to the two-dimension GIS, the three-dimension GIS can give people the more true feeling of the external world. It displays the geographic space phenomenon by solid sculpt technology. So the research on three-dimension visualization system of geographic information has highly value.This paper studies the three-dimension modeling, spatial analysis, visualization of the three-dimension visualization system of geographic information and related technologies. The three-dimension modeling is to construct the three-dimension solid surface by plentiful discrete data point, and to save the data point information and the relation between points. In this thesis, the author discusses the process of constructing triangulated irregular network with discrete point and improves the algorithm of constructing Delaunay network. In order to realize the real-time display of the three-dimension scene, the author analyses the complicated terrain model simplification and multiresolution representation, and brings forward a view-dependent dynamic multiresolution model and its related algorithm. Spatial analysis is an important characteristic and one of the primary targets of GIS, so the author researches the analysis of the basic topographic factor, visibility, contour, flood submerging. In the end, the author discusses the process of visualization, and researches the technology of hidden-line, illumination, texture mapping and animation. The three-dimension spatial data visualization can provide more direct and actual object for the management and decision-making. The research on this subject has considerable value for implementing the three-dimension visualization system of geographic information.更多还原