生成八棱柱的3D图形 可以通过鼠标旋转 在八棱柱包围空间内 释放一只fly 做随机运动 如果碰壁 那么被碰撞的墙壁会变成深色 fly会停止运动-Octahedron 3D graphics generated by the mouse to rotate in the space surrounding the release of eight prism random motion if doing a fly crashed into a wall so the walls will turn dark fly will stop moving