this english dude
julian beever does trompe-l'œil chalk drawings on pavement surfaces aka awesome 3D shit. wikipedia says he's been doing it since the mid-1990s
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his works are done using a thing called
anamorphosis which creates the illusion of 3D when viewed from the right angle . . . for example, here is a chick in a swimming pool:
but this is how it actually looks from another angle:
I love this one! and how he poses in the pics like he is actually doing stuff in the environment he created
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Here is his offical website: http://users.skynet.be/J.Beever/ with more amazing pics. he does other art too, but I am mostly into the anamorphic shit