thefluffyslipper/mac-gimp3-gmic-installer

G'MIC is a popular image processing plug-in for the photo editor GIMP. On macOS, there are no ready-made G'MIC binaries for the newer GIMP 3.x release. This repository provides a single shell script that builds the G'MIC plug-in from source and installs it into your personal GIMP folder, so you can use it without compiling everything yourself by hand. To use it, you need a Mac running macOS 13 or newer, with GIMP 3.x installed. You also need Homebrew, a common package manager for macOS, and the Xcode Command Line Tools. You download the script, make it runnable, and execute it in a terminal. The script can take 10 to 30 minutes to compile. After it finishes, you restart your computer and run the script once more. When you open GIMP and load an image, the G'MIC option should appear under the Filters menu. The script does a fair amount of behind-the-scenes work. GIMP ships with the libraries the plug-in needs but lacks the development files required to build against it. The script reads your GIMP version, downloads the matching source code for the headers, and assembles a temporary development setup. It then compiles the G'MIC Qt interface using CMake, applies a small patch so the interface works correctly on macOS with X11, signs the resulting binary, and places it where GIMP can find it. It also installs XQuartz automatically, which fixes certain interactive functions like the Black and White Colorize tool. There are some limitations. When GIMP releases a minor update, such as moving from 3.2 to 3.4, the plug-in must be rebuilt by running the script again. The plug-in also depends on Qt and fftw from Homebrew, so those should not be removed while the plug-in is in use. The script supports an uninstall option and a help flag for other commands. The build recipe was originally developed by Sébastien Guyader and others, then automated and released here under a public domain license.