【作者】 王涛；

【导师】 李德仁； 眭海刚；

【作者基本信息】 武汉大学 ， 地图学与地理信息系统， 2005， 硕士

【摘要】 三维GIS的发展为我们展现了一个丰富多彩的现实世界。目前三维GIS中对于地形、建筑物、植被等静态目标的可视化表现已经有了较成熟的应用,但对于动态目标的可视化研究并不多见。目前人们利用仿真、科学计算可视化等技术对动态目标的可视化进行了一定的研究,而如何利用现有的可视化技术将现实世界中的动态目标如行驶的汽车、飘动的旗子、飞舞的蝴蝶等融入到三维GIS中还没有作深入的探讨。 本文针对目前三维GIS中的应用需求,提出了对动态目标研究的必要性和可行性,并对三维GIS中动态目标的应用作了初步的探讨。论文首先分析了动态目标的内涵及特性,并根据不同的特性提出了分类的标准,接着引入动态对象,将面向对象的三维空间数据模型加以扩展并给出了动态目标数据结构的设计方法。在简要介绍目前动态目标可视化方法的基础上,对三维GIS中应用较多的刚体目标和粒子系统的运动描述和可视化方法作了探讨。针对海量动态目标的简化和调度,本文引入了层次运动模型的思想,从可见性的判断,模型的简化,运动层次的简化等几个方面对运动刚体的LOD方法作了初步的探讨。针对粒子系统的特性,对其可见性判断的优化和LOD方法进行研究,提出了基于八叉树空间分割的粒子碰撞检测优化算法。最后,作者根据所研究的理论和方法,设计了动态目标可视化模块,融入到数码城市GIS软件CCGIS中,并给出了应用实例。更多还原

【Abstract】 The development of 3D GIS presents us a rich and colorful world. Currently, there are many mature applications in static objects visualization, such as terrain, buildings, vegetation, but there are not many researches into dynamic objects visualization. Presently, people have done some research on dynamic objects visualization using techniques such as simulation and visualization in scientific computing, but there are not many researches on integrating dynamic objects such as running cars, aflutter flags, flying butterflies into 3D GIS.In this paper, aiming at the application requirement of 3D GIS, the necessity and the feasibility of research on 3D dynamic objects is put forward, some work is done in the application of dynamic objects in 3D GIS. Firstly, the paper analyses the conception, the character, and classification of dynamic objects, and then proposes an object-oriented spatial data model and the method of designing the data structure for dynamic objects. Next, the paper summarizes the visualization method of dynamic objects. Furthermore, this paper discusses the movement character and visualization method of rigid body and particle system. Aiming at the simplification and dispatching of a great deal of dynamic objects, the paper introduces the LOD method of rigid body and particle system in a few aspects, such as visibility judging, model simplification, level of motion, collision detection. Finally, the module of dynamic object visualization of CCGIS software is illustrated.更多还原