基于引导线偏移的建筑网格生成方法  

An Architectural Grid Generation over Free-Form Surfaces Based on Guide Curve Offsetting

作　　者：王奇胜[1] 高博青[1] 吴慧 WANG Qisheng;GAO Boqing;WU Hui(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China;College of Public Administration,Zhejiang University of Finance &Economics,Hangzhou 310018,China)

机构地区：[1]浙江大学建筑工程学院,杭州310058 [2]浙江财经大学公共管理学院,杭州310018

出　　处：《上海交通大学学报》2019年第9期1040-1044,共5页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金资助项目(51678521,51778558)

摘　　要：为了生成规整、流畅的建筑网格,提出了直接在曲面上偏移引导线生成自由曲面网格的方法,即空间引导线法.在给定的曲面上,绘制光滑的曲线作为引导线;在延伸的曲面上偏移引导线上的所有基准点并拟合成曲线,即引导线的偏移线;以刚生成的偏移线为引导线,迭代地推进生成新的偏移线,得到一组按特定间距布置的偏移线;以偏移线为网格线进行分段、连线、裁剪等操作生成网格.进而,通过调整引导线的形态,调控网格走向;通过设置各基准点的偏移距离,控制网格大小;通过合并过近的偏移点,优化网格形态.算例表明:该方法生成的网格形状规整、线条流畅、走向可控,能更好地满足建筑需求.With the advent of architectural CAD applications,architects and designers could model almost any curved surface geometry imaginable,whereas it is not an obvious task for engineers to efficiently create a grid structure on a complex surface that meets the architectural requirements.To generate regular and fluent grids over free-form surfaces,a grid generation method is presented based offsetting the guide curve on the surface directly,called spatial guide curve method.Firstly,one or two curves were defined as guide curves on the surface.Secondly,reference points were decorated on the guide curve with reasonable spacings,and then were offset and fitted into an offset curve on the surface extended properly.Thirdly,taking the newly generated offset curve as the guide curve,new offset curves were generated iteratively,and thus a set of offset curves were arranged.Finally,taking the offset curves as grid lines,the final grid was generated by doing operations on offset curves,like segmenting,connecting,trimming,etc.The grid trend was controlled by the guide curve.The grid size was controlled by offset distances of reference points and the grid shape was optimized by merging offset points which were too close.Cases studies were provided to illustrate the successful execution of these procedures.The results show that the grids generated by this method have advantages of regular shapes,fluent lines and desired trend,thereby satisfying aesthetic requirements.

关 键 词：自由曲面 网格结构 引导线 网格生成 

分 类 号：TU311.41[建筑科学—结构工程]