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Jason

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[Mar. 2nd, 2011|08:38 pm]
Jason
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More fun with Perlin-ish noise.

I'm a bit unclear on what the exact difference is between Perlin's actual algorithm, which prescribes randomly-gradiented locally linear patches at the vertices, (and then smoothly interpolating) and what I just did here, which is just assigning random scalar values to the vertices (and then smoothly interpolating).

One consequence of the simple random value version that becomes apparent to me now is that, in the time dimension, the animation definitely slides from state to state and appears to pause, very-un-lava-lamp-like, at each one.
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Comments:
[User Picture]From: gustavolacerda
2011-03-03 06:22 am (UTC)
Are you not convinced that they are different? It's clear to me that a random walk is very different from i.i.d. noise. I suspect that the random walk should exhibit fractal structure, namely the zigzagging at multiple scales.

By "smoothly interpolating" do you perhaps mean "smoothing", or are you preserving the points?
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From: dwindlehop
2011-03-04 11:33 pm (UTC)
Just gonna quote Perlin:

"Noise is band-limited - almost all of its energy (when looked at as a signal) is concentrated in a small part of the frequency spectrum. High frequencies (visually small details) and low frequencies (large shapes) contribute very little energy. Its appearance is similar to what you'd get if you took a big block of random values and blurred it (ie: convolved with a gaussian kernel). Although that would be quite expensive to compute."
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