Variable Spatial Resolution: Quadtrees
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چکیده
The concept of variable spatial resolution implies varying sized units at a given resolution level. The choise of the shape is a special matter. The square is particular handy if the process of creating the blocks of varying size is one of the decomposing space from a general level to more detail. For example, a polygon can be successively approximated by sets of blocks at different levels: If the process involves systematic splitting of space in 2-dimensional space by a rule of four, then the structure is known as a quadtree, a type of hierarchical data model. A 3-dimensional equivalent is known as an octtree because it involves an eightfold splitting:
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