An octree is a tree data structure in which each internal node has exactly eight children. Octrees are most often used to partition a three dimensional space by recursively subdividing it into eight octants. Octrees are the three-dimensional analog of quadtree

Quadtree

A quadtree is a tree data structure in which each internal node has exactly four children. Quadtrees are most often used to partition a two dimensional space by recursively subdividing it into four quadrants or regions. The regions may be square or rectangular, or may have arbitrary shapes. This...

s. The name is formed from oct + tree, and normally written "octree", not "octtree". Octrees are often used in 3D graphics and 3D game engine

Game engine

A game engine is a system designed for the creation and development of video games. There are many game engines that are designed to work on video game consoles and personal computers...

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Each node in an octree subdivides the space it represents into eight octant

Octant

An octant is one of eight divisions.-Octant in the plane :Traditionally wind direction is given as one of the 8 octants because that is more accurate than merely giving one of the 4 quadrants, and the wind vane typically does not have enough accuracy to bother with more precise indication.-Octant...

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