In this Gimp plugin GEGL does an awesome neon glow stick effect.
Windows C:\Users<YOUR NAME>\AppData\Local\gegl-0.4\plug-ins
Linux /home/(USERNAME)/.local/share/gegl-0.4/plug-ins
Linux (Flatpak) /home/(USERNAME)/.var/app/org.gimp.GIMP/data/gegl-0.4/plug-ins
To compile and install you will need the GEGL header files (libgegl-dev on
Debian based distributions or gegl on Arch Linux) and meson (meson on
most distributions).
meson setup --buildtype=release build
ninja -C build
If you have an older version of gegl you may need to copy to ~/.local/share/gegl-0.3/plug-ins
instead (on Ubuntu 18.04 for example).
The easiest way to compile this project on Windows is by using msys2. Download and install it from here: https://www.msys2.org/



