Going off of http://adrianb.io/2014/08/09/perlinnoise.html

I created a Perlin noise generator from scratch. Then I assigned the value range to some colors + lattices to simulate an archipelago!

Reload to get a new one. Download + press Z to save a particularly cute set of vectors that generate that island (will save under proc_map_vectors.json.p8l)

Pretty proud of how this turned out. I didn't port the code, per se, rather I wrote it from 0 with just the algorithm logic. Hope it's educational!

UPDATE: Use X to generate a new set of islands without having to reload the page