Graphical projection Perspective projection is a linear projection where three dimensional objects are projected on a "picture plane". This has the effect that distant objects appear smaller than nearer objects. It also means that lines which are parallel in nature (that is, meet at the point at infinity) appear to intersect in the projected image, for example if railways are pictured with perspective projection, they appear to converge towards a single point, called vanishing point. Photographic lenses and the human eye work in the same way, therefore perspective projection looks most realistic. Perspective projection is usually categorized into "one-point", "two-point" and "three-point
Point-to-point transit focus cities. In Europe, for example, most traditional full-service airlines operate seasonal point-to-point service outside their hubs to serve Mediterranean and Alpine holiday resorts. 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.,