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OpenGL动画编程。用窗口初始化函数，窗口处理和事件处理函数，定义场景绘制循环函数，三维物体绘制函数，空闲事件处理函数等来进行书写程序-OpenGL animation programming. Initialization function with the window, window treatment and event handlers, custom scene rendering loop function, three-dimensional object drawing fu