View source for Hacking:Building

This page contains things that you should know in order to build GIMP.
__TOC__

== Prerequisites ==
* You should know roughly how to use a terminal and the command line.
* You should know roughly what are environment variables. 


== GIMP's dependencies ==
Gimp depends on quite a few libraries, including but not limited to:
* [[Wikipedia:GLib|GLib]] – a library used by many gnome applications, containing utilities and common data structures for programs written in C. 
* [[Wikipedia:GObject|GObject]] - a library for implemnting objects (as in Object-Oriented-Programming) in C.
* [[Wikipedia:GTK+|GTK+]] – a graphical toolkit for building cross-platform user interfaces. GIMP 2.99 and later need GTK 3.0.
* [[Wikipedia:Cairo_(graphics)|Cairo]] – a 2D graphics library, used for drawing some of GIMP’s widget and also used by Gtk+.
* Python-Cairo: Python bindings for Cairo
* [[Wikipedia:Pango|Pango]] – a library for laying out and rendering text, used also in Gtk+.
* [[Wikipedia:MyPaint|MyPaint]] - a painting library that allows a lot of flexibility for brushes; it needs both libmypaint (the libmypaint-v1 branch) and mypaint-brushes (the v1.3.x branch).

GIMP's core depends also on two libraries which are mainly (but not only) intended to be used with GIMP:
* [[Wikipedia:GEGL#babl|babl]] – a library for converting between pixel formats, heavily used by GIMP when communicating with GEGL. 
* [[Wikipedia:GEGL|GEGL]] – a graph based image processing library, heavily used in GIMP’s core.
:To build GIMP 2.10, you need the GEGL version from git branch 'gegl-0-4'.
:To build GIMP master (= the development version of GIMP), you need the GEGL version from git branch 'master'.

Some of GIMP's plugins depend on (at least) the following libraries
* [[Wikipedia:librsvg|librsvg]] – a library for rendering [[Wikipedia:Scalable_Vector_Graphics|SVG]] files. 
* [http://www.libpng.org/pub/png/libpng.html libpng] – a library for reading and writing [[Wikipedia:Portable_Network_Graphics|PNG]] image files. Used by Gtk+, GIMP and GEGL.
* [http://libexif.sourceforge.net/ libexif] - a library for manipulating exif data (image metadata).
* [http://wvware.sourceforge.net/libwmf.html libwmf] - a library for working with [[Wikipedia:Windows Metafile|WMF]] files.
* [http://www.libtiff.org/ libtiff] - a library for reading and writing [[Wikipedia:Tagged_Image_File_Format|TIFF]] image files.
* [http://libjpeg.sourceforge.net/ libjpeg] - a library for reading and writing [[Wikipedia:JPEG|JPEG]] image files.
* [http://www.littlecms.com/ liblcms] - the Little Color Management System, a library for working with color profiles.
This list is incomplete.

See also the file [https://gitlab.gnome.org/GNOME/gimp/blob/gimp-2-10/INSTALL.in INSTALL] (or INSTALL.in in GIMP master).

== Build system ==

== Preparing for Building ==

You may need to install some software to build GIMP, including a C compiler, make, GNU autotools, meson, and more, plus many dependencies. See the OS-specific pages for details:
* [[Hacking:Building/Linux]] - Building GIMP on Linux
* [[Hacking: Building/Mac OSX]] - Building GIMP on the Mac platform
* [[Hacking:Building/Windows]] - Building GIMP on Windows

<b>1. Choose a place to install everything, and set a variable to point to it:</b>

If you're building Gimp from master, you may not want to install it in your system prefix, as you may break your system Gimp installation, or get odd behavior, especially if you also have a system version of GIMP installed.

You should then create another prefix directory where Gimp (and some dependencies) may be installed safely. On Linux you could use $HOME/.local. Let's name your custom prefix :

 GIMP_PREFIX=${HOME}/gimp_prefix

<b>3. Set some environment variables:</b>

Some dependencies may be installed in this prefix too, so the build system should be able to find them :

 # Used to find programs/tools during build
 export PATH="${GIMP_PREFIX}/bin:$PATH"
 
 # Used to detect the build dependencies
 export PKG_CONFIG_PATH="${GIMP_PREFIX}/lib/pkgconfig:${GIMP_PREFIX}/share/pkgconfig"
 
 # Used to find the glib-introspection dependencies
 export XDG_DATA_DIRS="${GIMP_PREFIX}/share:/usr/share:$XDG_DATA_DIRS"
 
 # Used to find the libraries at runtime
 export LD_LIBRARY_PATH="${GIMP_PREFIX}/lib:${LD_LIBRARY_PATH}"
 
 # Used by Autotools to find its tools
 export ACLOCAL_FLAGS="-I $INSTALL_PREFIX/share/aclocal $ACLOCAL_FLAGS"

Note: if you don't include the default value of XDG_DATA_DIRS, you may get a compile error trying to read a PNG icon file. You could try using this in that case:
 export XDG_DATA_DIRS="${GIMP_PREFIX}/share:/usr/local/share:/usr/share"

'''For Debian or derivatives (Ubuntu, Mint…) only:'''

Additionally to the previous commands (not in replacement), update some variables this way if you use a Debian derivative:
  arch="$(dpkg-architecture -qDEB_HOST_MULTIARCH 2> /dev/null)"
  export PKG_CONFIG_PATH="${GIMP_PREFIX}/lib/${arch}/pkgconfig:$PKG_CONFIG_PATH"
  export LD_LIBRARY_PATH="${GIMP_PREFIX}/lib/${arch}:$LD_LIBRARY_PATH"

== Download the source code ==

=== Download with git ===

This is preferred when working on the source code and developing Gimp.

 git clone https://gitlab.gnome.org/GNOME/babl.git
 git clone https://gitlab.gnome.org/GNOME/gegl.git
 git clone https://gitlab.gnome.org/GNOME/gimp.git

You can build specific versions by choosing a ''tag'' (a fixed git revision)…
 # List available tags
 git tag
 # Update the working directory to a specific tag :
 git checkout GIMP_2_10_12

… or a ''branch'' :
 # List available branches
 git branch -a
 # Checkout a branch :
 git checkout 
 git checkout -b wip/animation


If your distro does not provide them, you should get the Mypaint libs too : 

 git clone --branch libmypaint-v1 https://github.com/mypaint/libmypaint.git
 git clone --branch v1.3.x https://github.com/mypaint/mypaint-brushes.git

=== Download release archives ===

Gimp also provides release archives. This is preferred when building stable releases.

 https://download.gimp.org/pub/babl
 https://download.gimp.org/pub/gegl
 https://download.gimp.org/pub/gimp

Releases for mypaint can be found on their github page.

== Build the source code ==

=== Mypaint ===

For both Libmypaint '''''and Mypaint-brushes''''', use Autotools to install :

 cd libmypaint
 
 # Generate the configure script. That may be unnecessary with release archives :
 # If you might want to set special options, you can now run `./configure --help` to see what's available.
 ./autogen.sh
 
 # Configure the build (you can call ./configure --help):
 ./configure --prefix=${GIMP_PREFIX}
 
 # Build the code :
 make -j$(nproc) install
 
 cd ..

=== BABL and GEGL ===

Babl and Gegl use Meson. The build needs to be out-of-source, but the process is simple.

You can read the file meson_options.txt to find a list of options.

You may enable Link-time optimization (meson option <code>b_lto</code>)to have better performance.

 cd babl
 meson _build \
     --prefix=${GIMP_PREFIX} \
     --buildtype=release \
     -Db_lto=true
 
 cd _build
 ninja
 ninja install

Then repeat for gegl.

=== Gimp ===

Finally, you're ready to build Gimp!

You can choose between Autotools and Meson.

Meson is much faster than Autotools, but newer so considered "beta" quality.

==== Autotools build ====

The steps are similar to that for libmypaint, except that ./autogen.sh runs ./configure for you.

cd into the directory where you unpacked gegl.

If you're building source you checked out from git, run:

 ./autogen.sh --prefix=INSTALL_PREFIX

This generates a configure script and then runs it.

If you're building from a tarball, use configure instead of autogen:

 ./configure --prefix=INSTALL_PREFIX

You can run ```./configure --help``` if you want to see special options you can configure.

Check the output to make sure you aren't missing any features you might want.
Then:

 make && make install

==== Meson build ====

Numerous options are available to configure the build.

You should read the file <code>meson_options.txt</code> to know the options specific to this project.
Meson also provides some useful options, such as :

* <code>warning_level=[1, 2, 3]</code> : The level of compiler warnings
* <code>b_lto=true|false</code> : Enable link-time optimizations
* <code>b_coverage=true|false</code> : Enable coverage tools.
* <code>b_pgo=off|generate|use</code> : Enable profile guided optimizations
* <code>b_sanitize=none|address|thread|undefined|memory|address,undefined</code> : Use a code sanitizer


 cd gimp
 meson _build \
     --prefix=${GIMP_PREFIX} \
     --buildtype=release \
     -Djavascript=always \
     -Dlua=always \
     -Dpython=always
 
 cd _build
 ninja
 ninja install

==== Useful build options ====

You can customize the Gimp settings directory. This prevents any interference with other GIMP installations on the same computer.

* Autotools build : <code>--with-gimpdir=GIMP/git-master</code>
* Meson build : <code>-Dgimpdir=GIMP/git-master</code>

== Problems? ==

Most problems will occur during the configure stage, and with any luck it's just a missing package and the error message will make it clear what package you need. But there are more subtle problems that can occur. If you have a difficult error, look in:

[[Hacking:Problems_and_solutions]]

== Running Your New GIMP ==

You need to keep defined the same environment variables as for the build. You may want to define them in a script that you will source with : 

 source ~/gimp_definitions.sh

To keep those variables contained only for the execution of Gimp, you may want to use subshells : 

 (source ~/gimp_definitions.sh ; $GIMP_PREFIX/bin/gimp-2.10)


See the OS-specific pages for more specific advice:

* [[Hacking:Building/Linux]] - Building GIMP on Linux
* [[Hacking: Building/Mac OSX]] - Building GIMP on the Mac platform
* [[Hacking:Building/Windows]] - Building GIMP on Windows


== Build the web Gimp documentation ==
You can also build the documentation website (https://www.gimp.org/docs).

It uses <code>docbook</code> that requires some softwares, such as: 
 gettext
 automake
 docbook2odf
 pngcrush
 pngnq
 docbook-xsl 
 docbook-utils
 dblatex


Now, to build the documentation:

 git clone --depth=0 git@gitlab.gnome.org:GNOME/gimp-help.git
 cd gimp-help
 # Set this variable to your own language. It should correspond to a directory in the "po" source folder.
 export LINGUAS=en
 ./autogen.sh [--without-gimp ALL_LINGUAS="en"]
 make
 make pdf-local