Bounding volume: Difference between revisions

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A box approximation of an object used for collision & hit detection.
==AABB==
==AABB==
Axial-aligned bounding box, or AABB, stands for a 3D volume relative to a given origin.
'''A'''xial-aligned '''B'''ounding '''B'''ox stands for a 3D volume relative to a given origin. Effectively it is a cuboid which is not rotated. All of its edges are parallel to the axes it is alligned to.
 
==OBB==
==OBB==
Oriented bounding box, or OBB, stands for a 3D volume relative to a given origin and angle.
'''O'''riented '''B'''ounding '''B'''ox stands for a 3D volume relative to a given origin and angle.
 
==Difference==
==Difference==
In many applications the bounding box is aligned with the axes of the co-ordinate system, and it is then known as an axis-aligned bounding box (AABB). To distinguish the general case from an AABB, an arbitrary bounding box is sometimes called an oriented bounding box (OBB). AABBs are much simpler to test for intersection than OBBs, but have the disadvantage that when the model is rotated they cannot be simply rotated with it, but need to be recomputed.
In many applications the bounding box is aligned with the axes of the co-ordinate system, and it is then known as an AABB. To distinguish the general case from an AABB, an arbitrary bounding box is sometimes called an OBB. AABBs are much simpler to test for intersection than OBBs, but have the disadvantage that when the model is rotated they cannot be simply rotated with it, but need to be recomputed.
 
==See Also==
==See Also==
* [[Wikipedia:{{PAGENAME}}]]
* [[Wikipedia:{{PAGENAME}}]]
[[Category:Glossary]]
[[Category:Glossary]]

Revision as of 08:21, 2 September 2006

A box approximation of an object used for collision & hit detection.

AABB

Axial-aligned Bounding Box stands for a 3D volume relative to a given origin. Effectively it is a cuboid which is not rotated. All of its edges are parallel to the axes it is alligned to.

OBB

Oriented Bounding Box stands for a 3D volume relative to a given origin and angle.

Difference

In many applications the bounding box is aligned with the axes of the co-ordinate system, and it is then known as an AABB. To distinguish the general case from an AABB, an arbitrary bounding box is sometimes called an OBB. AABBs are much simpler to test for intersection than OBBs, but have the disadvantage that when the model is rotated they cannot be simply rotated with it, but need to be recomputed.

See Also