3D trick refers to converting 2D paintings and sculptures into 3D art in order to create an optical illusion for the eye. The museum used this method to fool the brain into believing what is obviously impossible. This is done by exploiting differences in perspective and the manner in which the artworks and paintings are created.
For the 3D trick to happen, visitors have to stand at a suggested point in front of the painting to create the illusion. It makes for some truly mind-bending and impossible looking photos and videos.