利用DWG格式地形图建立城市DEM

Creating urban DEM by use of topographic map with DWG format

采用VBA语言编程,提取离散高程点及其高程注记,并将高程点与高程注记匹配存储;对等高线进行有效的离散化,提取等高线的高程信息.而后将提取的高程数据在ArcGIS以三维可视化的人机交互的方式剔除粗差,最后生成DEM.实践证明,用此方法生成DEM速度快、精度高,是建立城市DEM的一种理想的方法.

VBA is a VB language embeded into AutoCAD which can be used to develop AutoCAD by ActiveX Automation interface.By using VBA,we can extract discrete elevation points and elevation annotions and store them in pairs;We can also extract elevation information by discretization of equal-high lines,eliminate errors of the extracted elevation data by the 3D method in ArcGIS and create DEM at last.Practice proves this method,being both fast and precise, is an ideal way of creating city DEM.