A new book collects the 3D street art of Kurt Wenner, a former NASA employee, who uses his mathematical skill to create three-dimensional illusions on pavements across the world. When viewed from the correct angle, people standing on top of them look like they are floating in thin air, and solid concrete can look like gaping chasms. Kurt has been perfecting his technique since 1982. Now, using the skills he has perfected over 30 years, he is able to create stereoscopic images, such as the one above enabling people to walk along imaginary webs slung by Spiderman.
For 25 years the artist has been using complex calculations from his old job - creating conceptual drawings of extraterrestrial landscapes at NASA - to bring floors and walls to life. Because of the emergence of computer-generated images, he was one of the very last artists to be trained how to mechanically replicate perspectives using pencil and paper and complex equations. But in 1982 he turned his back on space projects and, after selling all his belongings, moved from the USA to Italy where he applied his knowledge to art.
He says: "The pieces look real because they are calculated to be perfectly and mathematically accurate. It's exactly how they would look if the objects in my paintings were actually there. I use a piece of string to measure fixed points between the viewing location and the painting. This lets me calculate exactly how the perspective should be. It takes me around five to seven days to complete an average sized piece."
This was the first interactive 3D street painting, combining real people with their painted reflections. It was created during a street painting festival for a Swiss-German documentary in 1987 at Grazie Di Curtatone, Italy.
A Door to the Caribbean in New York City, April 2011. The pavement in front of the New York Stock Exchange was transformed into a luxury cruise ship, transporting the public to exotic destinations.
The three magi bring gifts to the children of Queretaro, Mexico, in December 2010
The Woman Driver in Bahrain, March 2008. This illusion of an F1 racecar had a hole cut out for the public to sit in and pose for pictures.
This work was created in Rome in March 2008 to celebrate the 500th anniversary of Leonardo da Vinci's arrival in Milan
Cyclist Bradley Wiggins leaves the Southbank for a ride through the rainforest, on a work called A Forest Path, October 2010
Kurt sits on a work called The Armchair Traveller in Waterloo Station, London, in January 2010
The Moneypit in Waterloo Station, October 2008. This image, showing a bank guard standing over a pit of banknotes, was the first stereoscopic work of pavement art ever created with Colorcode glasses.
A Million Signatures in Brussels, Belgium, in November 2010. The European Commission was presented with a million signatures requesting further study of genetically modified crops.
An early 3D anamorphic work in Lucerne, Switzerland, 1985
This is one of three interactive pavement art pieces commissioned for Buick motor company in 2009 in Herald Square in New York
A model of the Herald Square work. The pavement art was combined with a vertical panel for extra height, to take advantage of the limited space
A Car displayed looks so natural
Aqua Panna at the V Wine Cellars in Napa, California
A drawing for a piece of 3D art of a dragon in 2010 in Taiwan
The artist's wizardry with the world's streets has now been brought together in his new book 'Asphalt Renaissance', by Sterling Innovation publishers, available now through Amazon.
Portrait of Kurt Wenner in London