程序功能的说明如下所示 图形打印：实现系统的图形打印功能。-function of procedures shown in the graph below Print : achieving system's graphics printing function.

程序运行Bresenham的直线算法，所用坐标系为笛卡尔直角坐标系， 起始状态：用户输入所画线段的起点和终点坐标（要求起点横坐标小于终点横坐标） 结束状态：程序打印出所画线段-Bresenham run a straight line algorithm, used for the Cartesian coordinates Cartesian coordinate system, the initial state: the user to enter the painting o

一个小型CAD绘图系统，具有图元绘制、拾取、保存、修改、编辑、打印功能。-A small-scale CAD drawing system, with pixel rendering, pick, save, modify, edit, print function.