Once upon a time, I used to be a reasonably active poster on comp.graphics.rendering.raytracing. Sufficiently so that one poor soul approached me for help on the subject of heightfields in PoVRay, which he didn't understand at all. I did my best to help - although I don't know if I did any good! - and as a thank-you the gentleman concerned sent me a couple of fractal images he'd created. This was one of them (Click on the thumbnail for the full-sized image):
Well, if you want to showcase how heightfields work, an image like this is an ideal candidate. In a heightfield, each different colour in the .GIF file corresponds to a different elevation. In this file, the subtle banding in the shades of blue shows clearly where each elevation 'step' is going to be. The lightest shade of blue is the highest elevation; black is the lowest. So I created a demo scene that used his .GIF file as a heightfield object and sent him back a reply with my newly-rendered image and the POV source code I'd used to create it. As an example of how heightfields work, it's hard to think of a more clear-cut case. Anyway, my effort is a pretty trivial scene, technically speaking, but it's also quite restful to look at (I think!), and it's educational, too, so here it is (click on the thumbnail for the full-sized picture):
If you want to see the POV source code that I used, click here. (On most browsers, you can shift-click or control-click if you want to save the source code to look at it later.) If you want to render the scene yourself, you will need to save a copy of the blue fractal .GIF file as well.
The blue/purple colouring of the pool was my own creation. As far as I recall, the fiery sky colours that are reflected in the sea were part of one of the free sample pictures supplied with PoVRay, as was the idea of using a chrome sea. I don't recall which scene it was, but doubtless I'll come across it again before too long and when I do I'll update this information accordingly.
And thanks go to 'Knute' (wherever you are now) for sending me the lovely fractal I used as the basis of the picture. I hope your PoV-efforts bore fruit.
