Artists from around the world have dedicated themselves to 3D Art, also known as 3D Street Art or 3D Chalk Street Art. In fact, three-dimensional optical illusion is achieved, depending on the viewpoint of the beholder of a painting. The illusions are created using craters, objects, people, all done just painting the floor and applying the right perspective.
Some images are going for a more realistic way, while others are pure fantasy. The use of light and shadow, painting on the floor, and even with the aid of wall portions, walkways and stairs, helps create the 3D effect. They are also made in adhesives, floor, PVC, and used in marketing campaigns (floorstickers).
See some 18 such fantastic work of this kind that fits into the graphite family and seek inspiration to maybe create your own optical illusions.