Research On BIM Visualization Methods Based On WebGL

Building information model is a new technology in recent years.It has become a new trend in the construction industry,which is of great practical value during the entire construction cycle from design,construction to operation and maintenance.At present,most of the mainstream BIM servers are C/S Structs,but the desktop applications based on C/S Structs do have certain requirements for both software,hardware and software users.With the development of the Internet and the popularity of mobile terminals,the Visualization of BIM in the Web terminal has become a potential demand for BIM practitioners.Therefore,it is necessary to study the visualization method of BIM based on WebGL.In this paper,we treat the BIM constructed by the Revit as the experimental data,from which we extract Visualization information for BIM in the Web terminal with Revit secondary development technology.Then the visualization platform of BIM has been set up after the study of the WebGL visualization technology.Eventually the 3D display and interaction has been realized with good user experience.The principal tasks are as follows:The BIM data has been analyzed,and the Revit secondary development technology has been used.We have programmed the data extraction plug-in with C# language by using Revit2016 software and the Microsoft Visual Studio2012.And also have analyzed the extracted BIM data in the JSON format.The BIM data in the JSON format is loaded by using WebGL technology to realize its lightweight reconstruction in web environment.Moreover,the relevantknowledge of computer graphics has been used to achieve the BIM interaction like drag,zoom,rotation,scene roaming by using the methods of ray intersection,matrix operation,track ball lens control.The LOD optimization algorithm is introduced into the WebGL technology to achieve the relative balance of GPU rendering and rendering speed.Based on the above contents,the visualization platform of BIM is developed.The experimental results show that the BIM model visualization method based on WebGL is effective,and finally the Web end visualization platform of BIM model is realized,and the interactive effect is good.