地理坐标与球面三角网格快速转换、剖分模型的等面积和等形状性质对于全球网格(global grid)应用于空间信息管理具有同等重要性。在等弧长比投影族球面正二十面体投影基础上设计了球面三角四叉树剖分模型(EARPIH)。该剖分模型支持2种构建方式,包括投影平面均匀三角网格法以及直接球面剖分法。坐标转换简化为投影点与投影平面均匀三角网格之间的空间关系。通过弦长分布、紧凑度、面积等指数,将该模型与SQT,QTM,ISEA等已知球面剖分模型进行了面积和形状特性方面的比较分析。
Fast transferring between geodetic coordinates and sphere triangle facets is of the same importance as properties of equal area and shape for global grid using for spatial information. Based on the spherical icosahedron case of Equal Angle Ratio Projections (EARP), a new Spherical Triangle regional Quadtree (EARPIH) is constructed. There are two ways to build up the partition model: one is to evenly discompose the triangle projection plane and the other is to discompose the sphere directly. The coordinate transformation can deduce to locate a point into the evenly triangle network. The partition model is compared with several famous models such as SQT, QTM and ISEA by the indices, including distribution of chords, compaction, and area.