Power Fractal Fake Erosion Details

Started by AP, December 09, 2010, 07:22:31 PM

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AP

Has anyone ever tried adding a small stretched fractal noise over an existing power fractal for a type of faked-erosion rather then using the alpine shader. I would have no definite idea onto how to attempt this, however i do know there must be a way of using the noise details to follow and weave down the slope of the existing power fractal.

Henry Blewer

I do this often. It's not ideal. Use a negative displacement on a ridged type power fractal. Stretch the Y noise to 1.8. Use a distribution shader to constrain the slope and/or coverage. The scales, displacement, roughness, fractal noise, and spike values have to be 'eyeballed'.
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AP

Interesting. OK, i will post the results soon here.

AP

All that the noise does is scatter. It does not follow the slope very well. It's more like random pit depressions even at 500 along the y axis. No matter though. Perhaps i will just wait for speed optimizations and additions for the alpine shader.

FrankB

this is why your idea doesn't work.

The alpine can be both (relatively) fast and slow, depending on the changes to make to its settings. But the output still doesn't seem ideal. I think its results have to be enriched with additional fractal detail... which costs more time.

Regards,
Frank

AP

Well, i will wait until what ever comes down the line. Even if it takes years. Thankfully i am still young.    ;D

bobbystahr

Quote from: ChrisC on December 10, 2010, 05:29:53 PM
Well, i will wait until what ever comes down the line. Even if it takes years. Thankfully i am still young.    ;D

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