Introduction to the buildsystem

SCons

Godot uses SCons to build. We love it, we are not changing it for anything else. We are not even sure other build systems are up to the task of building Godot. We constantly get requests to move the build system to CMake, or Visual Studio, but this is not going to happen. There are many reasons why we have chosen SCons over other alternatives, for example:

  • Godot can be compiled for a dozen different platforms. All PC platforms, all mobile platforms, many consoles, and many web-based platforms (such as HTML5 and Chrome PNACL).
  • Developers often need to compile for several of the platforms at the same time, or even different targets of the same platform. They can’t afford reconfiguring and rebuilding the project each time. SCons can do this with no sweat, without breaking the builds.
  • SCons will never break a build no matter how many changes, configurations, additions, removals etc. You have more chances to die struck by lightning than needing to clean and rebuild in SCons.
  • Godot build process is not simple. Several files are generated by code (binders), others are parsed (shaders), and others need to offer customization (plugins). This requires complex logic which is easier to write in an actual programming language (like Python) rather than using a mostly macro-based language only meant for building.
  • Godot build process makes heavy use of cross compiling tools. Each platform has a specific detection process, and all these must be handled as specific cases with special code written for each.

So, please try to keep an open mind and get at least a little familiar with it if you are planning to build Godot yourself.

Setup

Please refer to the documentation for Compiling for Android, Compiling for iOS, Compiling for OSX, Compiling for Universal Windows Platform, Compiling for the Web, Compiling for Windows and Compiling for X11 (Linux, *BSD).

Note that for Windows/Visual Studio, you need to use x86_x64 Cross Tools Command Prompt for VS 2017 or similar, depending on your install, instead of the standard Windows command prompt to enter the commands below.

Platform selection

Godot’s build system will begin by detecting the platforms it can build for. If not detected, the platform will simply not appear on the list of available platforms. The build requirements for each platform are described in the rest of this tutorial section.

SCons is invoked by just calling scons.

However, this will do nothing except list the available platforms, for example:

user@host:~/godot$ scons
scons: Reading SConscript files ...
No valid target platform selected.
The following were detected:
    android
    server
    javascript
    windows
    x11

Please run scons again with argument: platform=<string>
scons: done reading SConscript files.
scons: Building targets ...
scons: `.' is up to date.
scons: done building targets.

To build for a platform (for example, x11), run with the platform= (or just p= to make it short) argument:

user@host:~/godot$ scons platform=x11

This will start the build process, which will take a while. If you want scons to build faster, use the -j <cores> parameter to specify how many cores will be used for the build. Or just leave it using one core, so you can use your computer for something else :)

Example for using 4 cores:

user@host:~/godot$ scons platform=x11 -j 4

Note that there are currently issues with parallel builds for at least some users, so if you are running into errors, try building without the -j parameter.

Resulting binary

The resulting binaries will be placed in the bin/ subdirectory, generally with this naming convention:

godot.<platform>.[opt].[tools/debug].<architecture>[extension]

For the previous build attempt the result would look like this:

user@host:~/godot$ ls bin
bin/godot.x11.tools.64

This means that the binary is for X11, is not optimized, has tools (the whole editor) compiled in, and is meant for 64 bits.

A Windows binary with the same configuration will look like this.

C:\GODOT> DIR BIN/
godot.windows.tools.64.exe

Just copy that binary to wherever you like, as it contains the project manager, editor and all means to execute the game. However, it lacks the data to export it to the different platforms. For that the export templates are needed (which can be either downloaded from godotengine.org, or you can build them yourself).

Aside from that, there are a few standard options that can be set in all build targets, and which will be explained below.

Tools

Tools are enabled by default in all PC targets (Linux, Windows, macOS), disabled for everything else. Disabling tools produces a binary that can run projects but that does not include the editor or the project manager.

scons platform=<platform> tools=yes/no

Target

Target controls optimization and debug flags. Each mode means:

  • debug: Build with C++ debugging symbols, runtime checks (performs checks and reports error) and none to little optimization.
  • release_debug: Build without C++ debugging symbols and optimization, but keep the runtime checks (performs checks and reports errors). Official binaries use this configuration.
  • release: Build without symbols, with optimization and with little to no runtime checks. This target can’t be used together with tools=yes, as the tools require some debug functionality and run-time checks to run.
scons platform=<platform> target=debug/release_debug/release

This flag appends the “.debug” suffix (for debug), or “.tools” (for debug with tools enabled). When optimization is enabled (release) it appends the “.opt” suffix.

Bits

Bits is meant to control the CPU or OS version intended to run the binaries. It is focused mostly on desktop platforms and ignored everywhere else.

  • 32: Build binaries for 32 bits platform.
  • 64: Build binaries for 64 bits platform.
  • default: Build whatever the build system feels is best. On Linux this depends on the host platform (if not cross compiling), on Mac it defaults to 64 bits and on Windows it defaults to 32 bits.
scons platform=<platform> bits=default/32/64

This flag appends “.32” or “.64” suffixes to resulting binaries when relevant.

Export templates

Official export templates are downloaded from the Godot Engine site: godotengine.org. However, you might want to build them yourself (in case you want newer ones, you are using custom modules, or simply don’t trust your own shadow).

If you download the official export templates package and unzip it, you will notice that most are just optimized binaries or packages for each platform:

android_debug.apk
android_release.apk
javascript_debug.zip
javascript_release.zip
linux_server_32
linux_server_64
linux_x11_32_debug
linux_x11_32_release
linux_x11_64_debug
linux_x11_64_release
osx.zip
version.txt
windows_32_debug.exe
windows_32_release.exe
windows_64_debug.exe
windows_64_release.exe

To create those yourself, just follow the instructions detailed for each platform in this same tutorial section. Each platform explains how to create its own template.

If you are developing for multiple platforms, macOS is definitely the most convenient host platform for cross compilation, since you can cross-compile for almost every target (except for UWP). Linux and Windows come in second place, but Linux has the advantage of being the easier platform to set this up.