Index structure for multi-scale representation of multi-dimensional spatial data in WebGIS
WebGIS中多维空间数据多尺度表达索引结构*

To solve the problem that existing data structure cannot support the multiscale representation of multi-dimensional spatial data in WebGIS, this paper put forward a modified data structure: a) getting the main tree from the deformation of the index structure of region quadtree partitioned on the basis of the rule of pyramid structure; b) possessing the sub-tree structure supporting the overlap of multi-dimensional spatial data; c)reflecting the changes in spatial resolution using the depth of the tree; d)all the nodes of the tree are the container of spatial objects. Analyzed the necessity of generating the index which was described. The algorithm for data generation of index structure, discussed the support to the multi-dimensional data and the query process. For the same data source, provided some comparative experiments using this structure and layer. The result shows that this index method can represent and search massive multi-dimensional spatial data effectively in WebGIS. The structure has been used in Shanghai multi-dimensional WebGIS system.