Diamond Discrete Grid Subdivision Method for Spherical Surface with Icosahedron

Diamond discrete grids of spherical surface can meet the requirements of multi-scale spatial data modeling and analysis due to the advantages of simple structure and uniform directionality.This paper presents a new diamond discrete grid subdivision method for spherical surface with icosahedron.Firstly,the location of the icosahedron's vertexes on the spherical surface are determined according to the earth's major geographical features.Secondly,to solve the problem of grid convergence in poles,transformation relation between the latitude and longitude coordinates and 3DCartesian coordinates are created.Then,a recursive subdivision approach of spherical diamond discrete grids is provided,and the geometric deformation of subdivision result is analyzed in terms of cell area and cell axial ratio.Finally,the feasibility of the method proposed is verified.The experiment results show that our subdivision method can construct spherical diamond discrete grids with icosahedron effectively,of which the general geometric characteristics are much better than that of the diamond discrete grids with octahedron.