![\"landscape\"](\"https:\/\/theindiestone.com\/binky\/wp-content\/uploads\/landscape.png\")
<\/a><\/p>\nA couple of things to note: Firstly, it tiles in both directions which is handy. Secondly, it’s not very Perlin Noise-y. That’s because I didn’t use any kind of noise function to generate it – well, I sort of did (I’ll get to that), but not in the conventional way.<\/p>\n
Perlin Noise (or more accurately nowadays, Simplex Noise) is probably the world’s handiest algorithm ever for generating textures. We’ve all seen it, we all know what it is, so there’s no reason to go into it beyond this extremely crude example:<\/p>\n
Read more here<\/a><\/p>\n Yeah?\u00a0It’s basically that except not using regular sine-waves, but instead adding together interpolated random noise –\u00a0for every iteration the frequency of the noise goes up and the amount it contributes goes down.\u00a0When using Perlin Noise\u00a0to generate your noise values, the result of cumulative additions (each time doubling the frequency and halving the intensity) is\u00a0that classic\u00a0turbulence<\/em> look which is so synonymous with Perlin Noise that we often call the texture itself<\/em> Perlin Noise:<\/p>\n (Okay, this is Photoshop’s Cloud Filter. But it’s basically the same and, for all I know, might actually be coded using Perlin Noise)<\/p>\n Anyway, I bring this up not because of any of this\u00a0specifically, but because the principle it operates on (add together lots of things to build up interesting structured noise) is the principle my landscape generators work on. This principle can generate you really interesting landscapes irrespective of what it is you’re using to add together to produce your final result. So your source could be an unstructured random mess but the act of adding lots of it together – each time the input contributing less than the previous iteration – can produce ordered structure.<\/p>\n So for my landscape, what was my input? Well, I just repeatedly added\u00a0sine-wave strips (where each strip’s orientation – either horizontal or vertical – and its position, thickness, amplitude, and frequency were random). So the first iteration would look like this, for example:<\/p>\n And iteration two, could look like this:<\/p>\n Keep going, then render it with landscapey colours and you end up with something like my landscape above. It’s\u00a0dead simple and you can use absolutely anything for your iterative additions – sine-wave strips, filled circles, filled squares, various pictures of cows – anything. Because anything<\/em> added together sufficiently, will eventually produce something which looks like structured noise – which makes playing with your inputs kind of fun \ud83d\ude42<\/p>\n So – now knowing that my landscape is just lots and lots of sine-strips, looking at it again it’s really really really<\/em> flupping obvious:<\/p>\n Here’s a landscape\u00a0where I used filled circles (with random positions, radii, and strength – where the strength also diminishes with each iteration), where the circles were filled like a crater such that in cross-section they’d look sorta like this:<\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n