3D WebGIS Platform Development Orenting Interactive Modeling And Thematic Analysis And Its Application Study

3D WebGIS is one of the new trends of current scientific development of GIS.Compared with 2D WebGIS,3D WebGIS's expression for the objective world can bring people more realistic experience.A few outstanding 3D WebGIS platforms and application have been developed which are maturing in showing 3D scenes and roaming,but there are still some shortages in such visual 3D analysis as 3D models and statistical data of thematic maps.Therefore,the article presents a method of creating and editing 3D models on the browser server,designs and achieves a 3D WebGIS tool platform of online interactive modeling and thematic analysis which is based on WebGL.The core functions of the platform are also packaged and applied to the 3D system of agriculture distribution planning.The main contents in the thesis are as follow:(1)The article made an in-depth research on many core technologies like interactive building and rendering of 3D models on Web,the storage mechanism optimization of a batch models,correlating thematic statistics and spatial data,and data communication between foreground and background.Meanwhile,it also studied and applied two emerging technologies of 3D slicing and WebVR,designed and achieved the technology road map of fast building large-scale 3D scenes and technology solutions of roaming in 3D scenes by virtual reality technology.(2)The article designed and developed a 3D WebGIS platform of B/S architecture without plug-in.It also analyzed the fields of overall framework of the platform,function design and table structure design of the database.What's more,the thesis combined the technologies of WebGL,Ajax and data storage,used Cesium as the class library of the front end and CCGIS Server as the background map server,programmed for interactive 3D modeling,3D thematic maps,WebVR,spatial measurement by HTML and JavaScript.(3)The system applied and explored online 3D modeling interfaces,implemen ted such functions as agricultural planning constructing of 3D with collaboration,vie w synchronization and scheme review.It also analyzed the thematic sequence of agric ultural production distribution data including time dimension by mapping interfaces o f thematic 3D map.Meanwhile,we developed some auxiliary functions,like route pla nning of field investigation,statistical reporting and user management,which are help ful to planning agricultural production distribution and improving scientific level of a gricultural production management.