用opengl来实现三维场景的漫游。 其中墙壁是用bmp图片纹理。 不具备撞墙返回功能。 用键盘方向键控制视角。-Use opengl to achieve three-dimensional scene roaming. One wall is bmp image texture. Do not have the wall to return to function. Using the keyboard arrow keys to control the angle.