自动构建多边形是地理数据拓扑关系建立的重点和难点之一,其算法的自动化、速度和复杂性一直制约着GIS中有关模块的设计开发和地理数据库的建立.针对该问题,通过研究,提出了一种基于方位角计算的多边形快速构建算法,很好地解决了多边形的构建及“岛屿”与“飞地”的处理问题.整个算法结构清晰,简单易懂,且程序设计易于实现.

Polygon construction is one of the most important and difficult parts in the establishments of topological relationships of geographic data, and its automation, speed and complexity hedge the development of related modules of GISs and the establishments of geographic data bases. A speedy polygon auto-construction algorithm based on azimuth calculation is put forward in this paper, which constructs polygons and deals with the problems of“islands”and“enclaves”successfully. The algorithm's structure is concise, easily understandable and conveniently programmable.