"Curves" on a power fractal?

Started by cbalaskas, April 14, 2007, 07:19:11 PM

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cbalaskas

Is it possible to affect a power fractal with a device (or series thereof) in a manner like "curve" in WM? Is it possible with functions (which I'm incredibly ignorant of)?

old_blaggard

Yes, it should technically be possible with functions.  You can also get a little bit of curving by increasing the warp in the distribution shader.  I've actually been working on a project that uses parametric functions to define a repeating spiral shape in order to simulate the coriolis effect.
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cbalaskas

I mean as in a height curve transform, to make canyons and glaciation and so forth. I see what you are saying though.

bigben

You can plug it into a colour adjust shader which will provide you with black/white level and gamma adjustment (a single curve). With some clever combinations you could be able to produce different variations

cbalaskas

bigben, gave your suggestion a try. It only seems to affect the color of the fractal, and not the heightfield itself.

bigben

yes... I was thinking more along the lines of a fractal used as a displacement function of a surface shader  ;)  This works but it's not a method you'd use for a terrain.

cbalaskas

Hey, that kinda worked! I'd really love to figure out how to have defined steps though. Thanks if anyone can figure that out for the math challenged.

Oshyan

There is currently no easy way to do this on the built-in procedural devices. BigBen's suggestion would work to some degree although it would be a little tricky to setup. The Colour Adjust shader does only affect the color, not the displacement, but if you used it on a Power Fractal that then fed into the Displacement input of a Default Shader or the Shader input of a Heightfield Generator, etc. (all this within the Terrain group), then it should work.

- Oshyan