显然,每个平面图都有一个无界面。
A plane graph together with the set of faces it determines is called a plane map.一个平面图与它所确定的面的集的总体称为一个平面地图。
In this paper, we gave the optimization method when drawing the plane graph on the computer screen.本文给出了在计算机屏幕上绘制平面图形时,提高其绘制效果的优化方法。