实现绘制各种情况直线的Bresenham算法，并将实现的算法应用于任意多边形的绘制，要求多边形的顶点由键盘输入或鼠标拾取，绘制的多边形顶点要准确，图形应该封闭。

要求掌握Bresenham算法的基本原理和算法设计，画出算法实现的程序流程图，使用C或者VC++实现算法，并演示。

-Implementation of the Bresenham line drawing algorithm for various situations, and to achieve an arbitrary polygon rendering algorithm is applied to require the polygon vertices from the keyboard input or mouse pick up and draw the polygon vertices to accurately, graphics should be closed. Bresenham algorithm required to master the basic theory and algorithm design, draw algorithm flow chart of procedures for the use of C or VC++ algorithm, and demonstrate.