HHRT-GAP-tree在多尺度显示中的应用

HHRT-GAP-tree in Multi-Scale Display Application

为了实现海量地图数据的分级多尺度显示,在地图数据库上构建HH-GAP-tree索引,并引入了拓扑算子。首先,确定显示比例尺级数,再生成多级Hilbert-R-tree索引,确定查询窗口。其次,对其建立GAP-tree索引,查询获取满足用户要求比例尺的初级数据,在此基础上检索GAP-tree并采用拓扑算子进行处理。最后,动态生成新的比例尺数据。实验结果表明,该索引在多尺度显示中是有效的,避免了单纯使用一种索引的缺点。

In order to implement the multi-scale display of massive map data,a new algorithm based on HH-GAP-tree index was proposed,and topo operators were brought in this algorithm.First,the number of the scales was confirmed,multi-level Hilbert-R-tree index was built according to the scale,and inquiring data was located in a query window.Second,the GAP-tree index was built for the data,and the data was processed by topological operators.Last,the new data was dynamically generated.The experiments results show that this algorithm is available in multi-scale display,and the shortcomings of either of index are avoided.