Terrain lines

Started by kevnar, February 28, 2010, 02:35:23 PM

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I'm trying to figure out how to get rid of the terrain lines (seen below). What causes those unnatural looking lines? How do you get rid of them? I see them on the fake stones too.

Just looking for some comments and advice. Thanks in advance.


It's inherent to certain types of perlin noise. In particular billowy, ridged and probably some of the mixed types too.
I don't think there is a way to get completely rid of them, except maybe using spike limit or other noise types/combinations of noise types.

(or building a low pass filter using functions, but this will increase render time)


I added a couple of extra fractal terrains with smaller scales. 10%, 1%, and 0.1% scale the first one. That seemed to "draw over" the lines good enough.


They are artifacts from the larger octaves of the noise. Adding smaller octaves will break them up appropriately. If you use few octaves of noise in a given shader this can happen. You can either use more overall octaves (or perhaps more roughness if you've already got >10 octaves), or you can use additional Power Fractals or other noise functions.

- Oshyan


Yep. That's how I got rid of the fractal lines in "Rocky Hills" (search it on this forum). Look closely in the left half of my image (assuming you have it up) and you'll see one big, fat, ugly fractal line. It was eliminated withmore PFs.
They just issued a tornado warning and said to stay away from windows. Does that mean I can't use my computer?