交互式绘图系统，图形用户界面，有橡皮筋法画直线、画圆、画Bezier曲线、裁剪等功能，用户可自行增加其他功能。-Interactive graphics systems, graphical user interface, a rubber band method drawing a straight line, circle, Bezier curve drawing, cutting and other functions, the user can add other features.