Hi,

I've sent this image URL to the list:

http://hopey.nervo.org/~gwidion/marble_1.png

Here is how it is done. Feel free to try and publish werever you like: I had not written the scirpt for that, but it is an easy one, just calling the described filters and procedures in the order described:

1) Paint horizontal strips of the desired colors on a blank image. I fashioned a specially crafted gradient file for this, but it could be done in a lot of ways: painting by hand, repeated use of filters->render->pattern->grid (zeroing the width for the vertical strips) . Another way: Sinus fiter, getting horizontal "sinusoidal" patterns, followed by map to gradient, followed by filters->colors->map->to gradient, followed by index image using few colors, or desired palette (and them back to RGB image), and a couple of other ways.

2) Create a new layer and fill it with the Sinus filter (filters->render->pattern->sinus. Zero out the "y" range (second slider) for vertical strips.

3) If desired, warp lightly the sinus layer with Iwarp (filters->distorts->iwarp)

4) Filters->map->displace, on main colored layer, using the sinus filled layer as parameter. Turn off X. Increase Y displace to about 160 - 200px.

5) If desired, apply iwarp fitler on resulting layer.

6) For making it tileable and increasing the "noise", use filters->map->make seamless.