I like stuff like this.
yeah block off each square so that you only see a small portion of each square and they are the same.
A few months ago, my algorithm to produce abstract art came up with the following picture:https://photobucket.com/albums/c66/Oso1138/?action=view¤t=chromostereopsis.jpgTo me, the red oval appears sunken into the screen. Several people, however, did not see the illusion at all, but only a flat picture of what could be a sunken oval. I wrote to a Japanese expert who has a site of optical illusions and he replied saying it was an example of chromostereopsis. Some people see it but most do not. Some even see red in front of other colours. I see it myself in the chatroom when people use different colours for their text, but when I asked others present, I was in a minority.