| 1. | Establishing 3 - d terrain models with vector contour lines and elevation terrain models with the help of the determination of space corresponding relations between contour lines , tile operation and branch operation . explanation of real - time reflection of terrain models , including three algorithms in lod technology , compared with quadtree algorithm , roam algorithm and the algorithm based on the intermediate belt , to show the advantages and disadvantages of the different situations of the terrains , so as to find out the right algorithm , the quadtree algorithm . developing and implementing the fast demonstration on the vc platform with three - dimentional visualization techniques , such as vrml and opengl , providing a persuasive argument for the research
论文首先概括介绍了用等高线快速建立3d地面模型和显示的相关技术,并论述了课题研究的背景和选题依据;其次,论文阐述了如何对等高线数据进行预处理,提出了有效的得到矢量化等高线的方法;再次用矢量化的等高线数据建立三维地面模型,通过等高线间的对应关系的确定、瓦片操作、分支操作建立地面的高程模型;然后论文对地面模型的实时渲染问题进行了深入阐述,主要是从lod技术的三种算法着手进行研究,通过对比四叉树算法、 roam算法和基于过渡带算法对不同种情况的地面数据显示的优缺点,再结合本系统的地形数据的特点选择了适合的算法:四叉树算法;最后,用vrml和基于opengl的三维可视化技术在vc平台上开发并实现了地形的三维快速显示系统,为论文的研究内容提供了有力的论证。 |
