nate robins 写的能改变函数参数观察效果的程序代码，希望对刚接触openGL的同志有用-nate robins written observation of the effect of function parameters can change the program code, in the hope that the comrades刚接触openGL useful

调研openGL的简单函数，画了一个机器人模型，可以控制机器人的动作-Research openGL simple function, drawing a robot model, can control the robot s movements