基于SuperMap平台的BIM轻量化处理及快速渲染技术研究  

Research on BIM lightweight processing and fast rendering technology based on the SuperMap platform

作　　者：宣洁 马亮 张京坡 韩金廷 XUAN Jie;MA Liang;ZHANG Jingpo;HAN Jinting(Natural Resources Information Center of Hebei,shijiazhuang 050000,China;SuperMap Software Co.,Ltd.,Beijing 100015,China)

机构地区：[1]河北省自然资源信息中心,石家庄050000 [2]北京超图软件股份有限公司,北京100015

出　　处：《时空信息学报》2023年第2期304-312,共9页JOURNAL OF SPATIO-TEMPORAL INFORMATION

基　　金：河北省省级科技计划项目(21567646H)。

摘　　要：针对当前固有的数据存储结构和数据读取展示效率难以支撑,大规模建筑信息模型(building information model,BIM)三维数据快速加载与渲染的问题,本文深入研究了模型轻量化和快速渲染技术。针对使用三角化几何描述的BIM,在最大程度保持模型外观不变的前提下,采用了Draco格网压缩算法,通过三角网模型的压缩达到数据逻辑结构轻量化的效果;在处理纹理结构复杂的BIM时,保持纹理清晰度的同时,采用CRN_DXT5技术,最大限度地压缩纹理数据;对于在外观相似、大量重复但空间位置不同的BIM构件,采用几何模型+姿态/位置矩阵的实例化的策略,实现相同几何模型的实例化压缩,大幅降低纹理的存储大小,实现BIM三维数据快速加载与渲染。同时,借助SuperMapiDesktop平台对优化前后数据源效率进行了验证,结果表明,经过轻量化处理的BIM浏览效率得到了大幅度提升。With the advent of smart city,urban construction is undergoing a transformation towards increased dynamism,efficiency,and refinement.The scope of 3D data models,which encompass building information model(BIM),city information model(CIM)and GIS technology,is expanding rapidly.In particular,within urban models,BIM can intricately showcase detailed information down to individual building components or facilities.However,this enhanced functionality comes with a significant increase in system load.The current inherent storage structure and data reading and display efficiency cannot meet the requirements of large-scale fast loading and rendering applications in 3D scenes.This paper conducts research on model lightweight and rendering technology,focusing on three aspects:model logical structure compression,model texture compression,and instance display.For BIM models represented by triangulated geometries,the optimization revolves around minimizing the number of triangular patches without altering the model’s appearance.The Draco mesh compression algorithm is used to compress the triangular mesh model and achieve lightweight data logical structure technology;In the case of intricate textured BIMs,an approach is adopted to maximize texture compression while maintaining the same texture clarity and minimizing texture size.CRN and DXT5 technologies are employed for texture compression;For BIM components with similar appearance and a large number of repetitions but different spatial positions,the instantiation strategy of geometric modeling along with posture/position matrix is adopted to achieve the instantiation compression of the exact Geometric modeling,speed up the decompression speed,significantly reduce the storage size of textures,and achieve rapid loading and rendering of BIM 3D data.The Arch Link Model sample data was used as the primary data source for testing,and the SuperMap iDesktop platform was used to verify the efficiency of the optimized and pre-optimized data sources.After lightweight processing,the BIM

关 键 词：轻量化技术 BIM 逻辑结构 纹理压缩 实例化 

分 类 号：TU17[建筑科学—建筑理论]