Lightweight Visualization Research Of Building Information Model Based On Web3D

The Building Information Model(BIM)integrates the data of each professional in the entire life cycle of the building,and achieves data sharing and interoperability through a unified business convergence platform to achieve collaboration among professionals.The use of computer graphics technology to achieve visualization of three-dimensional architectural models,so that it can be obtained,is the most intuitive way to achieve the sharing of architectural project professional information.As a computer graphics technology,Web3 D has the characteristics of cross-platform,easy operation and open and ready use.With the organic integration of Web3 D technology and BIM,it will greatly expand the informationization level of the construction industry,accelerate the depth and breadth of application of construction industry,and better serve the business collaboration and collaboration of all parties participating in the project.The 3D visualization data of Web3 D technology needs to be transmitted from the server to the browser through the network.Due to the limited network bandwidth and server performance,the visualization efficiency is not high.Especially when dealing with massive 3D data models,data loading takes a long time and even causes the system to crash.In order to improve the visualization efficiency of BIM,this paper proposes a lightweight method based on Web3 D for the visual application of building information model.This article first elaborates the related theories of the building information model,and analyzes the data structure of the IFC standard,including STEP(Standard for the Exchange of Product Model Data)which the base of IFC and the EXPRESS language that defines the IFC file format.While implementing the IFC file parsing,a corresponding visual 3D model was extracted.In order to effectively improve the efficiency of graphics rendering,this paper builds a hybrid index based on the division of indoor and outdoor space of buildings and multi-tree forests based on the characteristics of three-dimensional scenes of buildings.Finally,occlusion culling and view culling of building components are implemented,and data scheduling and loading are combined with multithreading and cache manager technology.In order to verify the lightweight effect of visualization of building information model,application instances such as scene bots,three-dimensional exhibition hall navigation and virtual reality experience were developed at the browser end,and the visualization application of BIM was analyzed and verified.Experiments show that the BIM lightweight visualization method proposed in this paper improves the efficiency of progressive loading of 3D visualization data and accelerates the drawing and rendering speed of model surface data.