基于六边形全球离散格网的海陆空图幅整合算法

Integration Algorithm of Land, Sea and Air Maps based onHexagonal Global Discrete Grid

海陆空图幅数据是一种遥感研究常用数据,但现有的海陆空数据都是基于矢量管理,在直观性、便捷性、统一性、高效性等方面存在问题。本研究利用全球离散格网无投影依赖、存储结构简单、全球无缝无叠等特点,提出基于六边形全球离散格网的海陆空图幅整合算法以解决上述问题。首先根据六边形剖分方法,将正二十面体投影到地球表面生成20个基三角形,并剖分组合成30个基六边形,其次确定比例尺与格网层级对应关系,递归剖分出对应比例尺层级格网数据,接着以直线段为最小单位,将海陆空图幅解析为多线段集—多线段—直线段的嵌套结构,利用格网邻接搜索算法将直线段格网化,最后生成以六边形全球离散格网形式表达的海陆空图幅数据。实验采用中国1∶50万和1∶25万海陆空图幅矢量数据和六边形全球离散格网数据,实验结果表明基于六边形全球离散格网的海陆空图幅整合算法可以完美地将图幅矢量数据转化为图幅格网数据。综上,基于六边形全球离散格网的海陆空图幅整合算法可以有效集成海陆空图幅数据,使海陆空图幅管理和显示更加便捷、高效,拓扑关系更加明确,为海陆一体化协同应用及利用全球离散格网进行数据集成与管理提供参考。

The integration of marine,land and air map data is a commonly used remote sensing data in research.However,existing marine,land and air data are based on vector management,which has problems in terms of intuitiveness,convenience,uniformity and efficiency.In this study,a hexagonal global discrete grid-based ma⁃rine,land and air map integration algorithm is proposed to solve these problems.Firstly,according to the hexag⁃onal subdivision method,the icosahedron is projected onto the earth’s surface to generate 20 basic triangles,which are then combined into 30 basic hexagons.Secondly,the corresponding relationship between scale and grid level is determined,and the corresponding scale level grid data is recursively subdivided.Then,the ma⁃rine,land and air map is parsed into a nested structure of multi-line segment sets,multi-line segments and straight line segments,with straight line segments being the minimum unit.The grid adjacency search algorithm is used to grid the straight line segments,and finally the marine,land and air map data is expressed in the form of a hexagonal global discrete grid.The experiment used 1∶50000 and 1∶25000 marine,land and air map vec⁃tor data in China and hexagonal global discrete grid data.The experimental results show that the marine,land and air map integration algorithm based on hexagonal global discrete grid can perfectly convert map vector data into map grid data.In summary,the marine,land and air map integration algorithm based on hexagonal global discrete grid can make marine,land and air map management and display more convenient and efficient,with clearer topological relationships,and provide reference for marine and land integration collaborative applications and data integration and management using global discrete grids.