3D Data Visualization Optimization Method Of Tilt Photography Based On WEB GIS For Game Engine

3D network GIS provides users with 3D geographic data acquisition,expression and simple spatial analysis services by integrating virtual reality system,large database,highperformance computer,transmitter and other equipment,which has broad development prospects.With the concept of digital twin gradually entering the stage of technology application,game engine and 3D GIS technology have a trend of integration and cross application.Game engine has better 3D data rendering technology and ecology than traditional GIS Engine,while GIS can provide basic spatial framework support,stronger data modeling ability,spatial information organization and analysis ability,etc.the combination of the two can achieve 3D GIS data visualization effect which is difficult to achieve in the past,and break through the existing 3D GIS Engine in the face of 3D model taking oblique photography as a typical example The limitation of loading time effect exists in the visualization of large-scale continuous triangulation model.Based on this,the optimization method of 3D data visualization of tilt photography for game engine Web GIS is studied:(1)Data integration optimization method for 3D tilt photography data based on game engineBased on the original data of the OSG format inclined photography 3D data,a 3D data structure was designed for the construction of the game engine dynamic grid,and the data transformation model was designed according to the characteristics of the data structure to realize the process of data transformation,simplification and storage.Furthermore,the spatial index of BSP map tiles and BSP 3D surface pieces was further constructed.Realize the lightweight integration of tilt photography 3D data for game engine,and provide data layer support for reducing network transmission time,improving data retrieval efficiency,and finally realizing the optimization of data visualization.(2)Implementation of culling algorithm based on LOD strategy and dynamic PVSCombining the patch culling and clipping algorithm based on visibility judgment,the culling algorithm based on latent visible set and the improved real-time optimization adaptive grid LOD strategy,a culling and clipping algorithm based on LOD strategy and dynamic PVS is constructed.From the perspective of graphics,improve the efficiency of data retrieval calculation,reduce the amount of data transmission and transmission time,and then realize the optimization of data retrieval process in the process of data visualization.(3)Data dynamic scheduling strategyIn order to improve the speed of data retrieval,combined with the characteristics of browser data cache,high performance,mutual isolation,easy migration and deployment of containers,a data cache mechanism is constructed in the client browser.Based on the characteristics of container technology,a number of data dynamic scheduling strategies are designed in the server,such as parallel computing,data copy retrieval,multi thread operation,etc.,to realize data retrieval from the perspective of computer science Then,the optimization of data retrieval process in the process of data visualization is realized.(4)Optimization method performance evaluation and prototype system design and ImplementationAccording to the optimization method,the evaluation index of the optimization effect and the index extraction scheme were designed.The factors to consider the effectiveness of dimensional data visualization mainly include image quality,number of triangle pieces,preloading time,loading time within the scene,memory consumption,frame rate and so on.Through multiple elements to measure data loading efficiency and the scene of fluency in running two indicators,and optimize efficiency according to measure visual optimization effect,design,implement and analyzed in this paper,method and the visualization method of static resource loading game engine performance contrast test,combining evaluation indexes,to verify the effectiveness of the optimization method,at the same time,according to the method,Design and implement the prototype application system.