摘要
为有效解决经纬度格网与四元三角网(Quaternary Triangular Mesh,QTM)在全球地形建模方面存在的不足,根据球面DQG(Degenerate Quadtree Grid)的几何结构特点,选择双线性多项式内插方法进行格网点高程内插,给出基于球面DQG的DEM建模算法与效率分析,并应用美国地质调查局提供的GTOPO30全球地形数据进行相关实验。结果表明:全球DEM建模时,DQG所需的格网数是经纬度格网或QTM的2/3左右,且可视化操作(图形放大、缩小及漫游等)时画面平滑、流畅,没有抖动。
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 analysis 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 cruising and so on） are good.
出处
《地理与地理信息科学》
CSCD
北大核心
2008年第5期33-35,39,共4页
Geography and Geo-Information Science
基金
国家自然科学基金资助项目"顾及多尺度地形的全球离散格网自适应建模研究"(40771169)
关键词
退化四叉树格网
地址码
高程内插
坐标转换
数字高程模型
degenerate quadtree grid
address code
elevation interpolating
coordinates translating
digital elevation modeling
