Julian Beever is an English chalk artist who has been creating trompe-l'œil chalk drawings on pavement surfaces since the mid-1990s. He uses a projection technique called anamorphosis to create the illusion of three dimensions when viewed from the correct angle.
It is often possible to position a person within the image as if they were interacting with the scene.
Beever first designs his work on paper. Once finalised a camera is placed at a distance from the art on the pacement which he returns to in order to observe the image through the lens a number of times, as the camera's wide angled lens can create an optical illusion which distorts the actual size of objects, which aides in maintaining perspective.
To buy a book on the pavement art of Julian Beever (Publishers website): http://www.fireflybooks.com/bookdetail&ean=9781554076611
For more information please visit http://en.wikipedia.org/wiki/Julian_Beever