3.5 V2D View Options
The button in the 3D Window toolbar and View->V2D View Options... command from 3D Window menu invoke V2D View Options dialogue with display settings dedicated for V2D projects.
It allows controlling the 3D display of the modelled axisymmetrical structure. Its angular slice between Start Angle and Stop Angle will be shown, divided into Sectors Nb., with lines between consecutive sectors invisible if Hide Sector Lines is checked.