This is more fun than custom font (at least I think so).

You can use this script to slap any image on top of a railing definition file (works similarly to custom font file where you can define your own railing definition .xcf file).

I have created a railing definition file as example and here i just ran script to slap image of buddha statue on the railing definition file...and this is what you get.


More details here-> Custom railing script for GIMP

Version 2 of script uses first 3 points of defined paths (point 4 is calculated based on first 3 points) produces better aligned railings.

That looks like a lot of fun. How does a railing definition file work?

it IS a lot of fun...
here's how the railing definition file is created: How to create custom railing definition file
I wrote this for version 1 of script. For version 2, you can define 4 points it just won't use the 4 th point and calculate it from the first 3 points (of each railing) and creates much more aligned result.

Just tested in GIMP 2.10 (Ubuntu flatpak installation).
Success.