If you haven't seen or tried Piranesi, it's hard to describe. It is basically a "paint" program--but it's easy to forget that when you're using it. In really tricky ways, it allows you to believe you are actually working in three dimensions--when in fact, as with all paint programs, you are working in two.
So if you are an architect who wants to produce a rendering that looks like a projection of a 3D model, but you are trying for the quality of a really good hand-produced image, Piranesi can help you do the job. You create your 3D model, then export it in one of the many formats Piranesi recognizes.
The program encodes the third dimension into the pixels of the paint program, and modulates the effect of whatever you do using that encoding. The result: Astonishingly realistic images, produced with relative ease.
Version 4, of course, has more, does more, than earlier versions. Well-worth checking out.
