OK -

I discovered what could become another use for this script... making mountain heightfields.

From above (gimp alone):
mtn_final.png

Rendered in 3D:
hf1.png


I started with a selection filled with a shaped spherical fill:
mtn_hf1.png

Then using this pattern I made:
pattern1.png

I ran the thatch script with 7 sides, no bumpmap or softlight, merging all layers down. I set the result to multiply, 30%:
mtn_hf2.png

cont...