气象要素场等值线图自动绘制

Isoline Drawing Programming of Meteorological Field Maps

根据业务的特殊性研制的气象要素等值线图绘制软件,通过把离散站点自动连接成符合Delaunay特性的不规则三角形网格,自动生成的等值线符合人们手工绘制等值线规则,可以绘制气象要素和北太平洋海温等值线分布图,绘制海陆边界并填充颜色。通过自定义的坐标系,很好地解决了屏幕坐标与实际坐标之间的转换、地图投影的实现等问题。程序具有丰富的绘图功能,可以根据需要手工绘制各种矢量图形对象和插入图像对象,能修改对象属性,包括随意移动位置、改变大小等,可以设置各种对象的显示顺序,能设置对象为Alpha混合透明显示。图形对象实现矢量级别的无级缩放,实现精细打印功能,满足日益发展的业务需求。

A program is developed to draw the isolines of meteorological element fields automatically by connecting discrete points into irregular triangle grids that conform to Delaunay features. The resulting isolines conform to the principles of isoline drawing by hand. The meteorological fields of Shandong Province and the sea surface temperature field of the North Pacific are drawn by the program, which include coastlines and color-filled areas. Through a user-defined coordinate system, it can switch between screen and actual coordinates and realize map projection, etc. The program has good drawing capability, can draw vector graphics, insert and revise the graphics, and set up the display order and Alpha mixing-transparence display. The graphics achieved the vector zoom without grades.