This picture demonstrates how viewpoint matters in perceiving impossible 3d objects.
Check out this site for an explanation on how it is done, the history of and the psychological mechanisms responsible.
And here are some more 3-d impossible structures and animated java demonstrations on how the illusions are possible.
Go here for the demos
There is a demo of the original impossible 3D object from the post a couple days ago at this site as well.
More like this
Last week's post on how sound affects perception of visual events was the most popular post ever on Cognitive Daily, with over 15,000 visits.
If Opabiniahad left descendants, what would they have looked like? That was the question on my mind as I fiddled around with the new Spore Creature-Creator last Friday night, tweaking my virtual creation this way and that in a bit of speculative biology.
Never mind that, though — Hybrid Medical Animation has a lovely demo reel of cells and molecules bouncing around.
Sometimes I get asked to do some demos for kids. I like this, it is fun. This week, I was asked to do just such a demo. Kind of as a historical record, I am going to document what I did.
Thank you so much for posting the "solutions". I was really wondering how the hell those figures were made. Though, even after seeing the explanation/rotations, they still look so real to me!
ohh yeah... thank Eamon and Brian for helping on this one :)