Research on globe distance survey based on globe subdivision

With the development of digital earth, Mathematical measure methods based on spherical surface have been extensively studied. The development of global subdivision theories have broken through the traditional measure methods of geodetic scientists. This article summarizes two typical global discrete grid system´s research achievements. Scholar Yuan builds a 12-connectivity distance survey method for triangular grid system. Inspired by his work, we proposed a method based on GeoSOT model by counting grids to fulfill the distance survey. In order to choose the right grids between two vertices to count edges, we employ the path finding algorithm A* in graph theories to find the shortest path. Experiments show that our algorithm is a good way to solve the affixed distance overlying the DEM.