Observing two objects from a viewpoint in 3d space, one may occlude another. This phenomena is called occlusion relation.

从某个视点观察两个三维空间中的对象时，一个对象遮住另一个对象的现象被称为空间遮蔽关系。

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Observing two objects from a viewpoint in 3d space, one may occlude another. This phenomena is called occlusion relation.

从某个视点观察两个三维空间中的对象时，一个对象遮住另一个对象的现象被称为空间遮蔽关系。

youdao