Development And Implementation Of3D Automatically Vector Drawing System In The Roads And Bridges Design

In recent years， municipal infrastructure is changing quickly with the rapiddevelopment of China’s cities， then its design’s quality and manifestations have ahigher， more stringent requirements.Now， the usual design of roads and bridges is touse the traditional design methods with computer-aided design (CAD) technology’shelp.For example： the design is Generally to express the three-dimensional position ofthe road，with a flat， vertical， horizontal two-dimensional plane in computersoftware，then the construction company will eventually put it in place in accordancewith that two-dimensional drawings; At the design stage,the design process and resultsare two-dimensional style， design comparison and optimization only rely on designdata and two-dimensional drawing. From an objective point of view， this is notintuitive， it is difficult to comprehensive show a three-dimensional effect of the designfrom a plan view，profile view，cross-sectional view;Then, in order to watch the roadsand bridges design three-dimensional effect in the later stages of design， we generallyrequire the use of three-dimensional modeling software (3DMax， Maya， etc.) tore-create the three-dimensional model in accordance with the results of two-dimensionaldesign drawings. It is the only methond we want to see the actual three-dimensionaleffect， the whole process is very time-consuming， laborious， imprecise (manythree-dimensional model are imprecise)，it can not accurately reflect the morphologicalnature of the target.Then, this issue want to study and solve this case.What this issue studied is the three-dimensional vector automatic drawing system,that use AutoCAD platform’s VisualLISP secondary development environment, the Lispprograms can receiving designers conventional two-dimensional design results(graphical and data),then automatically draw three-dimensional vector roads and bridges3D drawing, after calculation, it will complete to the final goals-one three-dimensionalvector Entity in AutoCAD. Its mechanism is the use of two-dimensional design data ofthe designers in the design process, the results will be translated into AutoCAD’s tableformat, and through the features of AutoCAD, it will automatically and quickly drawthe three-dimensional vector, or even the program will form a more perfect integrated design system. This project is not the usual methond of the roads and bridges design,and that is not to do the task of the professional3D modeling software too, but it mainlywant to help roads and bridges designers,when they design two-dimensionaldrawing,and get the existing data,they can draw the generate three-dimensional targetquickly and comfortably, so as to Show the design results of the three-dimensionalconcept. The results can be reported, display, verification, and provide a basis forprofessional3D design Basis to enhance the design efficiency. At the same time, it ishelp for reduce possible errors between the two-dimensional design andthree-dimensional design, and for reduce unnecessary time’s consumption, so, it isconducive to improve the quality of the design itself.