But would it then still be "perlin noise", and not just "addition of two sub-sampled and interpolated 2D digital signals"?
And what to use as input then... hmm.. maybe a picture of marco
No, I'll get off your back, just don't want you to make the common mistake to think that "random" in computer science is the same as "true random" in nature. "truly random" is impossible to implement in a computer. You have to make due with a special type of hash function with the same size input as output, and run it over and over again.
Its fully deterministic, and not strictly random, just random enough for all practical purposes...
What you do to make it "unpredictable" is to seed it with some real-life values, like user activity and time of day...
And, from a game design point of view, thats useful to know, because it means you can make "randomly generated" levels, that still is possible to re-create exactly each time... just save the seed used to create it... 4 bytes of data for a really complex level! (well, maybe a few more parameters
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(and also, it complicates all discussions of "gambling"...
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