Edge collapse of UDSM based on centroidal Voronoi diagram reconstruction

The adjacent meshes of the urban digital surface model (UDSM) are often subject to curvature upheavals, and these locations are details of the UDSM that should be preserved as much as possible during simplification. In order to solve this problem, the centroidal Voronoi diagram was introduced to repartition the mesh, and the point cloud density of the surface with small curvature could be greatly reduced. The size of the redrawn mesh surface was greatly different from that of the surrounding smooth triangular mesh. On this basis, the quadric error matrix edge collapse was used for levels of details (LOD) construction, and the area of obvious changes in the mesh could be greatly reduced. On the premise that the time performance and mesh error are similar to that of the direct edge simplification, the algorithm can save more simplified mesh details.