说明：  刚编二个CAD程序，有利于横断面相关制图和统计计算。 CAD点取多区域，标注多区域的总面积。 CAD选择一个填充图案，标注该填充图案的面积
(Just compiled two CAD programs, which are conducive to cross-section related drawing and statistical calculation. The CAD points take multiple areas and mark the total area of multiple areas. CAD selects a fill pattern, marking the area of the fill pattern)