I've been trying to find a bumpmap for rope for some little whole whale while.

And I have taken so many stabs at it with GIMP that I have had to replace my monitor.

Twice.

But by Jove (if you're reading this), I've found some Eureka. Kinda following these steps.

I made a black-on-white profile layer for Ofnuts (phantasmical) MapProfile filter (which is sometimes mayhaps quixotically referred to as ProfileMap), consisting of a sequence of little black circles lined up touching each other along the bottom of a white rectangle. I made the balls full height, and the rectangle about twice that high, my theory being that the resulting profile would be a range of grays instead of the full-range black-to-white.

I cropped the string of circles on the diameters of the end balls horizontally and then scaled the layer horizontally to be my perfect whatever (I think 300 px). Then I ran MapProfileMap and selected the result "Layers" layer and made a brush out of it, and then made a path along the diagonal of a new square white layer (in retrospect, I think a 60-deg angle, for a three-strand rope would be better--but that's only a suspicion) which I then stroked with the new brush.

That left me a diagonal pattern of hills and valleys, and if original black-circle placement was careful, made it possible to cut out a vertical rectangle in which each corner rested in a valley.

Pasting that as a new image, it was the work of a Genesis-day to draw two paths along the sides of the "near-rope" resting a node in each valley, and adjusting the handles of each node to "round" off the rope as it "bends around" out of sight. The two paths can be used to select the areas outside the desired rope which are then deleted.

One final task was to make a half-circle profile, as wide as the rope, and run MapProfile on it again, leaving a profile as wide as the rope and 1 px high, which can be scaled to be perfectly as long as the rope and moved to overlay it perfectly, and then moved above the rope layer and set to Multiply, perfectly.

A New-from-Visible layer should be a decent bumpmap for a rope. And more realistical ones might be fashioned from the introduction of noise and shimmy-shammy at various steps of the process.

To paraphrase that great philosopher, Yogi Berra, "Thank you, Ofnuts, for making this rope necessary."

Judicious (ha!) cutting and pasting and rotating could make bamboo parkay instead of rope.

("Gramp finally discovers 'herringbone'!")

I like the herringbone Gramps.

There is a animated rope brush here. Thank you Lyle.
viewtopic.php?f=4&t=4327&start=20#p53714

More animated brushes here.
viewtopic.php?f=12&t=7854