球面等积六边形离散网格的生成算法及变形分析

A Generation Algorithm of Spherical Equal-Area Hexagonal Discrete Gird and Analysis of Its Deformation

球面离散网格模型是管理海量数据的有效途径,如何构建球面网格是这类模型的基础问题。利用施奈德等积投影建立平面与球面的对应关系,并在此基础上设计了3种球面等积六边形离散网格的生成算法。结合实验分析这3种网格的最大/最小边长比和单元周长均方差两项指标,结果表明全部网格的指标均收敛,其中C-Ⅰ网格的性质最优。

Abstract： In recent years,a number of data structures for global geo- referenced data sets have been proposed based on regular,multi - resolution partitions of polyhedra and spherical discrete grid is the most promising of such systems. To get spherical equal - area hexagonal grids, this paper discussed five coordinate systems（CS） ： grid CS,medium CS, stand CS, vertex CS, and inverse Icosahedron Snyder Equal Area（ISEA） projection CS. Under these coordinate systems, the algorithms that translate hexagonal grid cells from an unfolded icosahedron to a sphere were put forward. And also the paper analyzed two targets, including ratio of maximum cell edge to minimum edge and the mean squared deviation of cell perimeter of all spherical grids that algorithms generated with experiment. The result indicates that both targets of all grids are all convergence and C- I grid fits for multi - resolution geographic information management among them.