GIS中统一于Q_i算子的多边形基本问题新算法  

New Algorithms for Basic Issues of GIS Polygons Achieved by Q_i Operator

作　　者：丁健[1] 江南[1] 芮挺[2] 

机构地区：[1]中国科学院南京地理与湖泊研究所 [2]解放军理工大学工程兵工程学院,南京市海福巷1号210007

出　　处：《武汉大学学报（信息科学版）》2006年第3期247-251,共5页Geomatics and Information Science of Wuhan University

基　　金：中国科学院知识创新工程领域前沿资助项目(CXNIGLAS-A02-012)

摘　　要：用Qi算子来描述多边形中边和连线两类矢量的方向角,归纳出由Qi算子所表示的矢量方向角在识别走向时的判断规则,从而成功建立了多边形4个基本问题的新算法。实现了4个算法在几何意义上的统一,并相对传统最优算法提高了执行效率,同时还保证了高可靠性和稳定性。In this paper, Qi operator is used to measure the azimuth of edges and connected lines which are vectors and related to the four basic issues. Principles judging to which side the following edge（connected line） turned relative to the current are founded. By deriving the direction relationship between the neighbouring edges（connected lines） based on these principles, the polygon＇s orientation, polygonal convexity-concavity can be identified, so does to point-in-polygon query. New algorithms are presented, the analysis shows that improved performance is achieved, and there is the unification of the geometry idea in solving those four issues.

关 键 词：多边形 方向识别 凹凸性识别 点包含判断 Qi算子 

分 类 号：P208[天文地球—地图制图学与地理信息工程]