First, the algorithm constitutes layered bounding box tree according to some rules, when making collision detection, the detection results of last time, will produce speedup effect.

该算法首先按照一定的规则建立起树形分层包围盒，在碰撞检测的时候，可利用上次的检测结果，起到了加速的作用。

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He crashed into the tree because he was trying not to hit a box that had fallen off the truck ahead of him.

他撞到树上，因为他试图不撞到前面卡车上掉下来的箱子。

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Once upon a time, there was a tree which wanted to become a treasure box.

从前，有一棵树想成为一个宝盒。

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Sorry, no freebies in the box like your Xmas tree lights -- we tried.

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Ron Arons set out to piece together his family's past after discovering a box of documents and a family tree following his parents' deaths.

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