一种基于球面QTM格网的面要素边界跟踪填充算法  

An Edge-Following Algorithm of Surface-Entity Based on the Spherical QTM Grid

作　　者：王谦 赵学胜[1] 李亚路 WANG Qian;ZHAO Xue-sheng;LI Ya-lu(College of Geoscience and Surveying Eng ineering , China University of Mining and Technology (Beijing), Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083

出　　处：《地理与地理信息科学》2019年第3期16-20,共5页Geography and Geo-Information Science

基　　金：国家自然科学基金面上项目(41671394;41671383)

摘　　要：为实现四元三角网(Quaternary Triangular Mesh,QTM)对球面面状要素矢量数据的离散化及可视化,该文将基于栅格单元的"边界代数法"扩展到球面三角格网单元,提出了一种基于QTM格网的边界跟踪填充算法,主要内容包括:通过ETP投影实现球面QTM格网与平面三角格网的相互转换,建立矢量线角度与三角格元邻近搜索的对应关系;"边界跟踪"并记录边界格元进行分类处理;最终给出"边界跟踪"下两种不同的填充模式。实验表明,该算法实现了球面矢量多边形在QTM格网中的填充。In order to realize the discretization and visualization of the vector data of spherical surface-entity on the QTM(quaternary triangular mesh) grid,the "edge-following algorithm" based on raster cell is extended to spherical triangular grid.An edge-following algorithm based on QTM grid is proposed in this paper.The main contents include:the realization of transforming between QTM and triangular grid on plane through ETP(equal-triangles projection),and establishing the mapping between the angle of vector line and the adjacent search of triangular lattice,"edge-following" and recording the boundary lattices,then processing them respectively.Finally,two different filling modes under "edge-following" are given.The experiment shows that this algorithm can fill the polygons in spherical QTM grid.

关 键 词：四元三角网 矢量 多边形填充 边界跟踪 

分 类 号：P208[天文地球—地图制图学与地理信息工程]