Perspective (graphical) on the horizon line. All lines parallel with the viewer's line of sight recede to the horizon towards this vanishing point. This is the standard "receding railroad tracks" phenomenon. A two-point drawing would have lines parallel to two different angles. Any number of vanishing points are possible in a drawing, one for each set of parallel lines that are at an angle relative to the plane of the drawing. Perspectives consisting of many parallel lines are observed most often when drawing architecture (architecture frequently uses lines parallel to the x, y, and z axes). Because it is rare to have
Point-to-point transit Point-to-point transit Point-to-point transit refers to a transportation system in which a plane, bus, or train travels directly to a destination, rather than going through a central hub. This differs from the spoke-hub distribution paradigm in which the transportation goes to a central location where passengers change to another train, bus, or plane to reach their destination. The point-to-point model is used widely by low cost carriers, including Allegiant Air and Southwest Airlines in the U.S., and European carriers such as Ryanair, easyJet and Wizzair. Many such airlines sell each flight leg independently and have no concept of round-trip ticketing