CAD图平面坐标转换算法与VBA实现

Coordinate Transformation in CAD Drawing and Its Realization Using VBA

当今,AutoCAD在设计施工与地形测绘中的应用已经相当的广泛,CAD图已经成为图形数据编辑和各种成果提交的主要形式。例如在施工放样桩位时,若工程桩施工图就是在其设计坐标系统下,则可以直接在图中"拾取"桩位坐标用于指导放样。但工程桩的图上坐标系统与其设计坐标系统往往并不一致,给设计和施工人员双方之间信息的共享带来了不便。本文以此为题,介绍了一种基于最小二乘的平面坐标转换算法,并针对该算法,给出CAD图坐标转换的VBA实现,最后结合一个施工放样工程桩的实际工程,验证了算法的可行性和软件在实际应用中的良好效果。

AutoCAD has widely used in construction design and terrain mapping,it also has become the main way of graphic data editing and products delivery. Take an example of staking piles,if the coordinate of piles in CAD drawing identify with the design coordinate,we can directly pick the point out from the drawing and obtain its coordinate to stake. Nevertheless,in most occasions they do not coincide,it brings a great many of difficulties to the sharing of information on design and construction side. This paper presents a study of this issue,a coordinate transformation model based on the least squares is established. A software using VBA is then established for the model. In the end through the analysis of a practical case,the model is proved to be feasible and the software also presents the good result.