Building OFP on Linux

Building OFP on Linux

This page builds OFP's engine and QtFRED from source on Linux. It follows the setup OFP's automated Linux builds use, but nobody has walked through it on a desktop machine yet. If something here doesn't match what you see, please let us know. For Windows see Building OFP on Windows, and for Mac see Building OFP on Mac.

If you only want to play or make a mod with OFP, you don't need any of this: see Using OFP with Knossos.NET.

What you need

You need a C++17 compiler (GCC 9 or newer, or Clang 16 or newer), CMake 3.21 or newer, Ninja, pkg-config and Git. The libraries the engine uses either build from OFP's source tree or are downloaded ready-made by CMake, so you don't need to install them yourself.

Ubuntu / Debian:

sudo apt install build-essential git cmake ninja-build pkg-config

Fedora:

sudo dnf install gcc gcc-c++ git cmake ninja-build pkgconf-pkg-config

Arch:

sudo pacman -S base-devel git cmake ninja

Ubuntu 22.04 and older ship a CMake older than 3.21. Get a newer one from cmake.org or with pip install cmake.

1. Get the source

git clone --recursive https://github.com/ofp-fs2open/fs2open.github.com.git OFP
cd OFP

If you already cloned without --recursive, run git submodule update --init --recursive inside the clone. Without the submodules, CMake stops with External submodules could not be found.

2. Configure

Make a build folder and run CMake from it. Replace ~/FreeSpace2 with the folder that holds your FreeSpace 2 data:

mkdir build
cd build
cmake -G Ninja .. \
  -DCMAKE_BUILD_TYPE=FastDebug \
  -DCMAKE_INSTALL_PREFIX="$HOME/FreeSpace2" \
  -DFSO_BUILD_INCLUDED_LIBS=ON \
  -DFFMPEG_USE_PRECOMPILED=ON \
  -DQT_USE_PRECOMPILED=ON

What the options do:

• CMAKE_BUILD_TYPE: FastDebug is optimized but keeps the debug checks for mod data, which is what modders usually want: it reports table and mission errors that Release skips. Release is for playing, Debug for running under a debugger.
• CMAKE_INSTALL_PREFIX: where ninja install copies the executables.
• FSO_BUILD_INCLUDED_LIBS=ON: builds Lua, jansson, libpng, libjpeg and zlib from OFP's source tree instead of using your system's copies.
• FFMPEG_USE_PRECOMPILED=ON: downloads ready-made LGPL FFmpeg libraries. Your distribution's FFmpeg is often a GPL build, and binaries built against it can't be shared with others.
• QT_USE_PRECOMPILED=ON: downloads a ready-made Qt 6 for QtFRED. To use your distribution's Qt 6 instead, leave this out and install its Qt 6 development packages (base, OpenGL and the help tools).

SDL3, OpenAL and FreeType use your system's copies when it has them, and are downloaded ready-made when it doesn't.

When it works, the last line is -- Build files have been written to: ....

Other useful options, added as -D<name>=<value>:

Option	Default	What it does
FSO_BUILD_QTFRED	ON	Build QtFRED.
FSO_BUILD_WITH_VULKAN	ON	Build the Vulkan renderer.
FSO_BUILD_WITH_OPENGL	ON	Build the OpenGL renderer.
FSO_BUILD_TESTS	OFF	Build the unit tests.
FSO_BUILD_TOOLS	OFF	Build some FSO tools.

3. Build

ninja install

This builds everything and copies the executables into CMAKE_INSTALL_PREFIX. The first build takes a while; later builds only rebuild what changed.

4. Run

Run the executables from your FreeSpace 2 folder, for example ./fs2_open_<version>-FASTDBG -mod MyMod. The exact names depend on the version and configuration. Settings, logs and pilots go in ~/.local/share/HardLightProductions/FreeSpaceOpen/.

If QtFRED won't start and complains about the xcb platform plugin, install your distribution's libxcb-cursor0 (Ubuntu/Debian) or xcb-util-cursor (Fedora, Arch) package.

Keeping up with OFP

git pull
git submodule update --init --recursive
cd build
ninja install

Ninja reruns CMake by itself when CMake files change. To start over with different options, delete the build folder and configure again.