Research On Lightweight Visualization Conversion Engine Based On Revit

With the development of the Building Information Modeling(BIM)building information model for nearly a decade,it has now been accepted by more and more workers in the construction industry.But at the same time,there are new problems.Divided into multiple stages in the actual project,but in different stages,the BIM model's operational authority is different.It is impractical for different roles under different stages to work on the same BIM model.Therefore,it is necessary to refine or summarize the BIM model,and according to the actual use of the model,the BIM model needs to be lightweight in order to be able to view the key information of the model at different stages.The more popular solution today is the lightweighting of the WebGL-based BIM model.This method refers to using a browser to browse and display complex 3D BIM models or 2D drawings on the web page without downloading or configuring any plug-ins.However,there are still many performance issues in many of today's solutions.The problem that this article studies is one of them,namely how to establish the citation relation to reduce the cache file size,improve the loading efficiency of the browser.This paper first analyzes the status quo of lightweight solutions for BIM models at home and abroad,describes the core technologies of lightweight solutions based on WebGL,and uses the APIs provided by BIM software to extract the geometric information and attribute information from the model and organize them effectively.New intermediate file.The user downloads the intermediate file to the local cache through the browser,and finally renders it through WebGL to reduce the weight of the model.Second,this article is an in-depth study of Autodesk Revit.Because it is considered that the software is a popular modeling tool in the construction industry,and provides a rich API to facilitate secondary development;introduced the data structure of objects in Revit,and elaborated the basic principles and basic ideas based on the secondary development of Revit.Then it analyzes an existing Revit-based BIM model transformation engine and studies its transformation process through its source code.It was found that the structure of the final intermediate document has problems and reasonable assumptions have been made.Finally,the proposed hypothesis is verified and gradually optimized.Design the data structure of new intermediate files and organize them with code;analyze and evaluate the results of the optimized intermediate file size and web page loading speed.The test results show that this optimization is effective.