I have been working at getting nicer looking coastlines in GIMP.

Here is my latest experiment:
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This consisted of a lower layer started with high detail rendered clouds, then high level detailed random difference clouds applied about 4 times.

Next layer up is rendered cloud, large scale, high detail. I kept changing the seed until I found a preview that had the shape I wanted. Set this mode to screen.

Top layer (my three-layer-sandwich standard technique for non-destructive coastline generation) is 50% grey set to lighten mode.

I went back and adjusted the middle layer levels to control the coast position and number of islands..

Select by colour (merged levels) and save selection to a channel.

I find the coast to be deliciously detailed, and there was absolutely no touch-up, I would think this is nice looking large continent scale....opinions?

(I might have to script this technique...since I like the results)

-Rob A>