Three-dimensional R tree spacial index method considering levels of detail

A multi-level of detail and spatial indexing technology, applied in the field of geographic information systems, can solve problems such as serious overlapping of nodes in the same layer, low efficiency of spatial query, irregular node shapes, etc. The effect of subtraction and node shape regularity
CN101692230AInactive Publication Date: 2010-04-07WUHAN UNIV +1
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
WUHAN UNIV
Publication Date
2010-04-07
Estimated Expiration
Not applicable · inactive patent

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Abstract

The invention discloses a three-dimensional R tree spacial index method considering levels of detail, which utilizes a globally optimal node selection method from bottom to top and then from top to bottom, selectively adopts a splitting mode of two into three and takes a newly-proposed three-dimensional Cauchy value as a node shape factor. The comprehensive evaluation index considering the node covering, overlapping and shape factors is enabled in the node selecting and node splitting operations, thereby ensuring the shape of the generated three-dimensional R tree to be reasonable. The management of levels of detail model is considered conveniently by means of a balanced hierarchical structure. The method supports the generation and inquiry of the spacial index of a two-dimensional and three-dimensional space target, has very high efficiencies of generation and inquiry, and can be applied to many professional fields correlative with the three-dimensional space such as various space database systems, three-dimensional roaming software and the like.
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Description

technical field

[0001] The invention belongs to the field of geographic information systems, and in particular relates to a three-dimensional R-tree spatial index method in consideration of multiple levels of detail. Background technique

[0002] With the development of geospatial data acquisition methods such as photogrammetry, laser scanning, geological exploration and other technologies, the acquisition accuracy and modeling speed of 3D model data have been continuously improved. It reduces the complexity of the scene, and makes the amount of data surge and the types of data diverse. At the same time, in order to express the authenticity of the scene, texture data and CAD models are also widely used, and multi-level of detail has become one of the important characteristics of true 3D spatial data. The CityGML 3D city model standard, which was adopted as the OGC standard in August 2008, already has content about the integrated expression of indoor and outdoor, and the des...

Claims

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