Ok, a tutorial is on its way, I had to learn how to do a couple of things in gimp (or PS) which I knew existed but I never used them.  It might still take me a few days to 'weave' it in other life things that need doing.But at least I know it all works.
I should have called the thread 'additional ' rather than 'alternative' way, as I'm not saying you cant achieve good things without it, just another tool in the toolbox. Up to now I also used the method of duplicating my terrain making it bigger in the horizontal directions and flatter in the vertical, or adding extra islands/rocks and making them invisible. It works but I found it a bit fiddly.
Bigbraader - I like your foam. The only thing I dont like is the fact that at the intersection with the coast it is a pure white line because the distance to object below is exactly 0, and its a bit tricky to get rid of that even if you combine it with other noises. (only the 'multiply' mode of the combiner can do it, if the ranges of numbers are right).
Sorry, probably will be clearer when I finish the tut.
Oh - its going to be an old fashioned one, words&pictures, not a video.
eonite - oh yes, another 'why didnt I think about it' about using the sine filter... very promising!

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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