The Design Of Scenery MOdeling Software Of Traffic Engineering Structure Based On OpenGL

With the rapid development of commutation,the application of computer in commutation is attached more and more extensive importance. In recent years,AutoCAD software has been generally used in drawing two-dimensional graphs in the design of traffic engineering structures such as ship and bridge. However,two-dimensional graphs can not reflect the three-dimensional effect of the traffic engineering structures,which makes the design of traffic engineering structures have some drawbacks both in aesthetics and in practice. Meantime the three-dimensional animated demonstrations have become the best method during the design of project selecting,project-bid inviting and design reporting. In a virtual view scene,only through traditional methods we can't attain a full-orientation investigation to transportation engineer structures to be built in a dynamic and interactive manner. Thus it is ne essary to develop a scenery modeling system of traffic engineering structure.This thesis describes a scenery modeling system of traffic engineer structures in microcomputer,which is based on the idea of Object-oriented. Taking ship as a main object and Visual C++6.0 and OpenGL as a programming tool,we develop a scenery modeling system of ship. This system builds up three-dimensional models of all kinds of ships using an interactive method and observes dynamically them in a virtual view scene. It can also draw the ship line drawings,which are used in the interactive computer aid design of the ship.For the specification of the curve surface of ship,this system applies three methods,i.e. triangle,B-spline and NURBS,to express the ship curved surface. It can transform offsets data into control-points data and subsequently build the scenery model of ship with these control points data. The three methods all have their advantages and disadvantages. We select one of them according to the hardware of computer and the precision required.With the idea of Object-oriented,this system develops a complete classstructure,which not only improves the efficiency of programming but also brings convenience to the further expansion of this system. Because Doubly Linked List can dynamically distribute store place,it is used in storing the offsets data of ship. Through adding and deleting the node,we can easily add the offsets data and modify the model.With the methods of parametric inputting,interactive inputting and graphic inputting,this system can build the three-dimensional models of ship and modify the model from time to time. Moreover,this system can transform the models into ship line drawings that include waterline drawings,transverse section drawings and vertical section drawings.After building up the model of ship,we can build up the virtual view scene of ocean and bank,interactively endow the ship with light and material,select an inspect or route,then observe dynamically the virtual ship and return to optimize the model of ship.In later chapter,this thesis discusses the basic frame of bridge scenery modeling system and gives a simple example of this system.