说明：  计算机图形综合实验四,摄像漫游与环视, 绘制至少一个三维物体及场景；在场景中添加上适当的光源,给物体贴上适当的纹理图, 实现摄像漫游：通过鼠标来上下左右地移动摄像机，也可通过键盘W、S、A和D键（或向上、向下、向左和向右方向键）来前后左右地移动摄像机,实现摄像机环视：通过鼠标或键盘旋转摄像机环顾四周，包括左右巡视、向上仰视和向下俯视
(Experiment IV computer graphics, camera roaming and looking around, drawing at least a three-dimensional objects and scenes in the scene to add the appropriate light source, objects affixed to the appropriate texture map to achieve roaming camera: up and down through the mouse to move the camera around, also available via the keyboard W, S, A and D keys (or up, down, left and right arrow keys) to move the camera around and realize we take a look at the camera: the mouse or keyboard through the rotation around the camera, including those about inspections upward and downward looking down looking up)