城市轨道交通线路的CPU/GPU协同快速建模方法  

A Fast CPU/GPU Cooperative Modeling Method of Urban Rail Transport Lines

作　　者：李鸣 魏庆朝[1] 吕希奎 LI Ming;WEI Qing-chao;LV Xi-kui(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;School of Traffic and Transportation Engineering,Shijiazhuang Tiedao University,Shijiazhuang Hebei 050043,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]石家庄铁道大学交通运输学院,河北石家庄050043

出　　处：《图学学报》2019年第4期644-650,共7页Journal of Graphics

基　　金：国家自然科学基金项目(51278316);北京市自然科学基金项目(8172040)

摘　　要：城市轨道交通线路三维可视化设计能有效地改进设计质量。针对传统基于CPU的线路三维建模方法存在着建模速度慢、等待设计成果时间长、渲染效率低、场景优化困难等问题,提出一种基于CPU离散-GPU建模的城市轨道交通线路三维模型快速建模方法。首先,将线路分为线状模型和点状模型,然后根据线形设计成果利用CPU分解线状模型得到离散化的边界条件,解析点状模型得到空间信息参数,分别形成独立的、数据量极小的离散数据包;然后利用GPU的并行计算能力通过离散数据包实现线路三维模型的快速建立;联合CPU的场景拣选能力和GPU的顶点扩展能力,建立了一种用于长线状模型显示的场景优化方法。研究结果显示:①该方法建模耗时仅为传统方法的0.55%~1.30%;②浏览体验相比基于传统CPU建模和场景管理的方法显著提升,最小帧数在70帧以上;③可有效降低内存及CPU占用率等性能指标,释放设计平台计算压力;④为线路三维可视化设计实用化提供了一种可借鉴的方法和思路。Three-dimensional (3D) visualization can greatly improve the quality and efficiency of urban rail lines design.However,the traditional CPU-based method of 3D modeling have some problems in modeling speed,render efficiency,optimization scene,which require to be improved urgently.A fast 3D modeling method of urban rail transport lines based on CPU discrete-GPU modeling is proposed.Firstly,the line is divided into linear models and point models,and then,according to the results of line design,CPU is used to decompose linear models to obtain dataset of discrete boundary conditions.Subsequently,the point models are analysed to obtain dataset of spatial information parameters which can form,independent discrete data packets with a small amount of data respectively.Finally,with these discrete data packets,the fast modeling of 3D line model is achieved owing to the parallel computing ability of GPU.Combining the scene picking ability of CPU with the vertex expansion ability of GPU,a kind of scene optimization method that applies to long linear model display is established.The results show that ① The time-consumed by this method is only 0.55%–1.30% of the time using traditional CPU-based method.② The proposed method is better than traditional CPU modeling method and scene management in browsing experience,minimum frames per second is higher than 70.③ The performance indicators such as occupancy of memory and CPU are greatly improved,which help to lessen the pressure of design platform.④ It provides significant implications for the 3D design of practical urban rail transport lines.

关 键 词：城市轨道交通 线路设计 三维线路建模 快速建模 

分 类 号：U212[交通运输工程—道路与铁道工程]