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    Perlin noise is great. processing has a decent implementation:

    https://processing.org/reference/noise_.html

    https://processing.org/reference/noiseDetail_.html

    My one pet peeve is that it doesn’t allow you to control individual octaves. And, although the value is always between 0 and 1, for many settings the outputs are more constrained than that.

    If I ever get a chance to take a real sabbatical, working on a library for precisely shaped noise would be high on my list.