圆弧+

“绘图”菜单和工具栏的附加命令，用于绘制圆弧、圆、多边形和椭圆，输入点、半径、长度、角度、切线、精度（段数）。适用于任何平面、任何线条、模型级别或嵌入组或组件中。
作者：Didier B.
Additionnal commands to the “Draw” menu and toolbar, to draw arcs, circles, polygons and ellipses, entering points, radius, length, angle, tangent, accuracy (number of segments). Works on any plane, witn any line,at model level or embeded in groups or components.