The picture we see doesn't look right! It seems like we can see the front faces of two cubes but then the shared central face would be impossible. * Click or <Space> key to see different patterns * One way of viewing this illusion is that you can see the front 3 faces of a cube on the left, and the back and bottom faces of another cube next to it on the right. I loaded 3D coordinates for the vertices of the two cubes, rotated them with 3D rotation code, and then projected these rotated coordinates onto the screen. Note: Another way of viewing this illusion (your mind will flip between the views) is that you can see the front 3 faces of a cube on the right, and the top and left faces of another cube next to it on the left. I find this view harder to see.
* The first pattern for the faces of the cubes does not have rotational symmetry. I ordered the vertices for each square face so that the right angle lines would be drawn around the square corner that I wanted. * The other patterns have rotational symmetry so can be drawn starting at any vertex.
