The Research Of Fast Constructing Topological Relationships Of Regional Spatial Data

Using spatial data with topological relationships can reduce the amount of data and can solve the problems of adjacency and network relationships. Constructing the topological relationships of spatial data is an important and difficult problem of GIS. The rapid evolution of GIS requires much to the basic technology system. Constructing the topological relationships regional spatial dada is a very important problem and it's necessary. Some related international forms had listed it as a research emphasis, Though the problem is important, traditional algorithms are inefficient and unavailable to large scale spatial data.The major contributions of the thesis is the algorithms system to construct the topological relationships of regional spatial data based on Triangulated Irregular Network (TIN).The following are detail contents of the thesis. Firstly, a fast algorithm of constructing TIN after pretreated points' data of line and label points is presented, and the maintenance methods of TIN is presented.Getting the points of line's intersection is a complicated problem in GIS. A fast algorithm by constraining lines to TIN is presented to solve this problem.Our methods of organizing arcs and constructing the topological relationships between arcs and between arcs and nodes, and methods of organizing polygons and constructing the topological relationships between polygons and between polygons and arcs, are also based on TIN, and they are all efficient.After studying the problems of attribution of islands and attribution of label points, a fast algorithms of attributing outer-polygons and a fast algorithms of attributing label points are presented. These two algorithms perfect our algorithms system.Fuzzy tolerance and methods of managing large scale spatial data are adopted to improve the stability and adaptability of our algorithms.This algorithms system fully uses the adjacency and adaptability of TIN. A lot of practices showed that this algorithms system is efficient stable and practical.