Overlay of Polygon Objects and Its Parallel Computational Strategies Using Simple Data Model
Shuqing Zhang · Geography and Geo-Information Science · 2013
Overlay of polygon objects is a spatial overlay analysis using divergent data layers and their corresponding attributes within specific region of interest.It can quantitatively investigate the scope and feature of interaction and function among different types of spatial objects.However,traditional single processor,single thread overlay computing model is hard to fulfill the demand of real time analysis and emergency decision upon massive and dynamic spatial data.Towards simple data model,this paper presents taxonomic description of polygon object features,which are composed of single polygon,multi-polygon and multiline polygon with numerous node data.Data filtering and parallel computational strategies using multi-level bounding boxes are further established.Meanwhile,besides the two traditional fundamental operations,i.e.point inclusionandline traversing(line intersection),a new category of fundamental operation calledcollinearis proposed.Thereby,we can quickly calculate the relative position of the intersection points and the nodes on a collinear edge when overlaying two polygons,and precisely judge whether the collinear edge is the boundary of theirintersection region.As the initial outcome,the efficacy of methodology proposed here has been proved under the circumstance of serial computation.