很好的学习视口的程序，能让你理解在屏幕傻瓜如何切分不同的视口-Good learning process, as the mouth, make you understand how to split the screen fool different viewports

用c++语言为基础，使用OpenGL的绘制方式，绘制简笔画的人和自行车，并实现分屏的功能(On the basis of c++ language, we use OpenGL drawing method to draw simple strokes of people and bicycles, and realize the function of split screen.)