Algorithm and Visualization of Digital Elevation Modeling Based on Spherical DQG
Yanli Gao · Geography and Geo-Information Science · 2008
To overcome the deficiency in global terrain modeling of both Longitude-Latitude Grid and Quaternary Triangular Mesh(QTM),bilinear-polynomial interpolating method is selected to get the elevation of DQG(Degenerate Quadtree Grid) nodes,the efficiency analyzing and algorithm of digital elevation modeling are given in details.In the end,experiment and analy-sis are implemented with the GTOPO30 data of USGS.The results show that the DEM grids number is about 2/3 of both Lon-gitude-Latitude Grid and QTM at the same level,and the effect of visualization operations(zooming in,zooming out and crui-sing and so on) are good.