一种大型带状数字地形模型建模方法

Modeling Method for Large Strip Digital Terrain Model

根据铁路选线系统海量地形数据的特点,以快速、自动为目标,通过在构网建模过程中对空白区域和分块边界的处理,综合利用图形子区边界提取、异侧找点、最短距离等原则,提出了一种基于约束Delaunay三角网建立大型带状三角网的快速建模方法.通过对建立的大型三角网模型进行四叉树分割和分块存储,有效提高了建模成果的利用效率.该方法已成功地用于“虚拟环境选线系统”的开发,通过几段实际线路的应用,证明了用此方法建立连续带状数字地形模型的有效性和可靠性.

From the characteristics of mass terrain data in a railway location system, a practical fast algorithm for strip digital terrain model （S-DTM） generation was proposed based on the constraint Delaunay TIN （ triangulated irregular network）. This method takes many of the characteristics of large strip terrain areas into consideration, such as obtaining the boundary of sub-areas, finding out points at different sides, shortest distance, characteristic lines, and special areas, etc. The decomposition and structure of quad-tree are used to large triangulated net models constructed to increase the efficiency the generation and application of S-DTMs. This method has been used in a virtual environmental railway location system. The result of application in several practical railway lines shows the validity and reliability of the proposed method to establishing continuous strip digital terrain models.