This funny bounding volume is an infinite plane that divides space into two regions: the part behind the normal, which is "inside" the bounding volume, and the part in front of the normal, which is "outside" the bounding volume.
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This funny bounding volume is an infinite plane that divides space into two regions: the part behind the normal, which is "inside" the bounding volume, and the part in front of the normal, which is "outside" the bounding volume.