Building GIMP for macOS

Table of Contents

The main GIMP building instructions are at Building GIMP. This page is for macOS-specific changes.

Supported macOS API

The supported versions of macOS are noted in the devel-docs/os-support.txt file of the GIMP source you cloned or downloaded.

GIMP project is favoring backward compatibility as a general rule and we really don’t like deprecating hardware when it is just a few years old. Nevertheless we may have to bump our macOS requirement when it becomes too hard to maintain. This is especially true as this OS has extremely low contribution rate while core system changes happen at nearly each macOS release. Sometimes, lowering compatibility with old versions is the only way to reduce hardship for the few contributor(s) we have.

Therefore if you find the minimum supported macOS version too high, the best solution would be to contribute.

Building GIMP natively under macOS using MacPorts

The files in the gimp-macos-build repo are used to build GIMP both locally and on Circle CI. Take a look in this folder.

To build locally, you need to clone the repo linked above to a folder called project in your home folder. Checkout gimp-2-10 for the stable branch and master for dev.

Setting up the environment

At a minimum, you will need to install:

Xcode Command Line Tools:

xcode-select --install

Also gtk-mac-bundler:

if [ ! -d ~/Source/gtk-mac-bundler ]; then
  mkdir -p ~/Source
  cd ~/Source
  git clone https://gitlab.gnome.org/lukaso/gtk-mac-bundler
  cd gtk-mac-bundler
  make install
fi

Then, install MacPorts with:

macports0_install.sh --homedirgimpX

To avoid issues with Homebrew versions of libraries being used instead of macports versions, it’s recommend disabling Homebrew somehow or taking care that login shell isn’t a Homebrew shell.

Finally, set this:

export VGIMP=X
export arch=Y

Change X to 2 if building the stable branch and 3 if the dev one.
If you use ARM64 change Y to arm64, and x86_64 if x64.

Building the software

You can’t follow the instruction on the main page. Be careful of the following changes:

Dependencies are builded with the following command:

macports1_install_packages.sh

And GIMP:

macports2_install_gimp.sh

Packaging

GIMP need to be packaged to be properly executed in macOS, so:

macports3_build_app.sh

The GIMP executable will be at ~/macports-gimp${VGIMP}-${arch}/bin/.

Additionally the script will create a staged version of the app in: ~/macports-gimp${VGIMP}-osx-app-${arch}, which can be run with:

~/gimp${VGIMP}-osx-app-${arch}/GIMP.app/Contents/MacOS/gimp

Notarization and Distribution

This script will create a DMG file which is the “installer”, if you wish:

macports4_build_dmg.sh

It can be find in /tmp/artifacts/

macports4_build_dmg.sh can fail if you don’t click Allow/OK in pop up to give permissions to access Finder in order to layout the DMG.

About code signing and security entitlements, these links have useful content. When these weren’t set correctly, the application, and specifically Python plug-ins fail to load and basically hung with no error messages.

Once you’ve used the scripts above, for a local build loop use the following script:

quick_build.sh

Any changes you make in the files under the work directory will be wiped out the next time you ask MacPorts to build GIMP. So, if you want to make changes to GIMP itself, once you have tested, copy them to a repo manually (or temporarily connect this repo to your remote).

Finally, if you need to start over from scratch, run:

macports_uninstall.sh