Generation method of 3D tunnel based on vector model

On the basis of vector model,this paper presented a method,which could generate 3D tunnel and smooth joints at the same time while making sure the shape of generated tunnel was correct.It planted a series of vertical sections on center lines firstly.After calculating starting points of parallel lines according to the tunnel shape,it got some points by using the parallel lines intersected with sections,and finally connected the corresponding points on adjacent sections to realize modeling.Concerning the tunnel spicing problem,the method inserted rotated sections on joints,generating tunnel and smoothing the joints at the same time.It ensures the seamlessness of tunnel joints and simplifies the method as well.