Research On Multi-Level Representation And Analysis Technology Of Vector Data For Web Map

With the rapid development of the Internet,traditional geographic information systems(GIS)have evolved into the network phase named Web GIS.The web map has gradually replaced the traditional electronic map.With the browser as the display window,more and more users can get access to it in real-time and concurrently.The widespread use of the fifth edition of the Hypertext Markup Language Standard(html5)on browsers and the maturity of vector tile technology have enabled current mainstream web maps(Google,Baidu)to render vector data directly.Because of the multi-level feature of network maps,it is increasingly necessary to perform multi-level representation and analysis for vector data rendered.This paper is based on web map consists of vector tiles and the main work is as follows:(1)Proposed a multi-level organization model of vector data for web map,and established the complete representation model of vector data and the relationship between vector features and map hierarchy.(2)Based on the multi-level organization model,studied the multi-level representation technique of the curve on the web map,and proposed the sampling method to achieve the representation of the curve.(3)Based on the multi-level organization model,studied the multi-level spatial analysis technology of 3D building vector data,and proposed a multi-level spatial retrieval method based on the proposed model.Realized the online multi-level sunlight analysis of 3D building entities,including multi-level sunlight occlusion analysis and multi-level sunlight intensity calculation.(4)Designed and implemented a multi-level representation and analysis prototype system for the vector data on web map which provides online vector data display,vector data multi-level representation and partial spatial analysis services.