用opengl来实现弹球按照预定轨迹运动，对opengl的学习有很大帮助。-Use opengl to achieve in accordance with the predetermined trajectory pinball campaign opengl learning helps a lot.

riyuedi 运动模型，日月地环绕，图形精致美观，轨迹合理-riyuedi motion model, sun and the moon is surrounded by exquisite beautiful graphics, a reasonable trajectory

Opengl:使用多边形区域，设计一个简单二维动画。其中的角色能按一定轨迹运动。本例中用小正方形在矩形框中移动，遇到边框则会弹回-Opengl:Design a simple 2 d animation.the role in the polygon could move according to a certain trajectory.the example describes a square moving in a rectangular box,which rebounds when