Circular cylinder is a basic move along a straight line trajectory can be considered as a collection of the same diameter of the circle, if the horizontal section of film, then it is a straight line.

圆筒是基本的圆沿着直线移动的轨迹，可以考虑为相同直径的圆的集合，如果水平放置节片的话它就是直线。

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Circular cylinder is a basic move along a straight line trajectory can be considered as a collection of the same diameter of the circle, if the horizontal section of film, then it is a straight line.

圆筒是基本的圆沿着直线移动的轨迹，可以考虑为相同直径的圆的集合，如果水平放置节片的话它就是直线。

youdao