Design And Implementation Of Real-scene Three-dimensional Police WebGIS System

With the rapid development of computer technology and geographic information system,spatial geographic information is widely used in various industries.In recent years,police geographic information system is a new field of information application of public security in China.In the construction and development of police information system,the application of two-dimensional police GIS is becoming more and more mature,but it is still in the exploratory development stage in the field of three-dimensional application.Traditional two-dimensional geographic information system has some shortcomings in the application of three-dimensional model visualization and complex spatial analysis.In order to truly reflect the three-dimensional scene of the city,and realize the sharing of multi-type information data across platforms and the application of dedicated police functions in the system,this paper introduces WebGIS technology and front-end development technology into police geographic information system,designs a roaming mode of virtual earth,takes Internet network as a bridge,realizes the visual query application of police geographic information and spatial analysis,gives full play to its advantages in police emergency management and command decision-making.The system provides a powerful visualization tool for all police affairs of public security informationization,the network structure of the system is beneficial to the integration and utilization of fragmented information resources and easy sharing.On the premise of improving the dynamic management efficiency of public security organs,it can effectively save the management cost of police work and promote the construction of intelligent police work.The research contents and results are as follows:(1)The system takes the city three-dimensional model as the data source,uses the aerial tilt photogrammetry technology to obtain the basic data such as multi-angle photographic images,studies and realizes the batch modeling of the city three-dimensional scene.Through the conversion of data format,realizes fast loading 3D scene model in Web client.(2)Aiming at the visualization of three-dimensional model data on browser side,the cross-platform display and sharing of information,this paper studies a WebGIS implementation mode based on JavaScript and WebGL technology,and designs a Web client based on B/S architecture,which enables users to browse visually and realize a good interactive experience of three-dimensional visualization in browsers without any plug-ins.(3)In order to meet the needs of police work,the author designs and develops map basic operations,spatial measurement,query and positioning,video surveillance and other functions,which improves the deficiencies of traditional two-dimensional geographic system application.The three-dimensional scene provides simulation environment support for emergency plan drilling,realizes spatial analysis based on measurable reality model,and improves the efficiency of daily work deployment of public security departments.