heyas; this is fun! :) here's a square function rotated 45 degrees for a rusty chain-link fence. and here's um.... actually, not sure quite what those are, some spot functions making a little future encampment... or a walled fort! okay, some stuff i learned: if you want just a function (ie: not to apply a function to a mountain or dunes, etc), reset the terrain to clear it. functions with lots of white will work on an empty terrain. if your function is very dark (ie: leopard spots), invert the terain first, it'll work better. the scale number works much like it usually does, the lower the scale, the more time the function repeats itself, in smaller iterations. i think 12 is actually the scale to use if you want one iteration of the function. um... well, it's some multiple of 3. :) the amplitude affects how high/low the function scale value makes the terrain. it goes from 0 to 100. around 30-40 is good. if the amplitude is too high and the scale is too small, you may end up with the function spiking itself out of existence. (experiment with the leopard spots, they're easy to see what's going on.) some functions dont seem to want to scale onto the terrain. the checkerboard functions, for example, only seem to make one square on the whole terrain. :/ the wood grain function and the vertical stripe one have their radial center in the lower left corner, and there's no talking them into putting that in the center of the terrain. (maybe if you reset the origin in the function editor.) i'm not sure what axis of the functions the terrain is actually following. to get the squares into diamonds for the chain link fence, i rotated the z to whatever (last slider) in the function edit: rotation deal. changed it to 45 degrees and got diamonds. besides making a new terrain out of functions, you can apply them on top of existing terrain features. (hmm, i'll have to try that for my fortress/city, try to make one on a hill.) you can also stack them on top of each other, but you might need to turn down the amplitude on functions that have strong blacks or whites.