Attention: Here be dragons

This is the latest (unstable) version of this documentation, which may document features not available in or compatible with released stable versions of Redot.

Compiling with .NET

Requirements

  • .NET SDK 8.0+

    You can use dotnet --info to check which .NET SDK versions are installed.

Enable the .NET module

Note

C# support for Redot has historically used the Mono runtime instead of the .NET Runtime and internally many things are still named mono instead of dotnet or otherwise referred to as mono.

By default, the .NET module is disabled when building. To enable it, add the option module_mono_enabled=yes to the SCons command line, while otherwise following the instructions for building the desired Redot binaries.

Generate the glue

Parts of the sources of the managed libraries are generated from the ClassDB. These source files must be generated before building the managed libraries. They can be generated by any .NET-enabled Redot editor binary by running it with the parameters --headless --generate-mono-glue followed by the path to an output directory. This path must be modules/mono/glue in the Redot directory:

<godot_binary> --headless --generate-mono-glue modules/mono/glue

This command will tell Redot to generate the C# bindings for the Redot API at modules/mono/glue/GodotSharp/GodotSharp/Generated, and the C# bindings for the editor tools at modules/mono/glue/GodotSharp/GodotSharpEditor/Generated. Once these files are generated, you can build Redot's managed libraries for all the desired targets without having to repeat this process.

<godot_binary> refers to the editor binary you compiled with the .NET module enabled. Its exact name will differ based on your system and configuration, but should be of the form bin/godot.<platform>.editor.<arch>.mono, e.g. bin/godot.linuxbsd.editor.x86_64.mono or bin/godot.windows.editor.x86_32.mono.exe. Be especially aware of the .mono suffix! If you've previously compiled Redot without .NET support, you might have similarly named binaries without this suffix. These binaries can't be used to generate the .NET glue.

Note

The glue sources must be regenerated every time the ClassDB-registered API changes. That is, for example, when a new method is registered to the scripting API or one of the parameters of such a method changes. Redot will print an error at startup if there is an API mismatch between ClassDB and the glue sources.

Building the managed libraries

Once you have generated the .NET glue, you can build the managed libraries with the build_assemblies.py script:

./modules/mono/build_scripts/build_assemblies.py --godot-output-dir=./bin

If everything went well, the GodotSharp directory, containing the managed libraries, should have been created in the bin directory.

Note

By default, all development builds share a version number, which can cause some issues with caching of the NuGet packages. To solve this issue either use GODOT_VERSION_STATUS to give every build a unique version or delete GodotNuGetFallbackFolder after every build to clear the package cache.

Unlike "classical" Redot builds, when building with the .NET module enabled (and depending on the target platform), a data directory may be created both for the editor and for exported projects. This directory is important for proper functioning and must be distributed together with Redot. More details about this directory in Data directory.

Build Platform

Provide the --godot-platform=<platform> argument to control for which platform specific the libraries are built. Omit this argument to build for the current system.

This currently only controls the inclusion of the support for Visual Studio as an external editor, the libraries are otherwise identical.

NuGet packages

The API assemblies, source generators, and custom MSBuild project SDK are distributed as NuGet packages. This is all transparent to the user, but it can make things complicated during development.

In order to use Redot with a development version of those packages, a local NuGet source must be created where MSBuild can find them.

First, pick a location for the local NuGet source. If you don't have a preference, create an empty directory at one of these recommended locations:

  • On Windows, C:\Users\<username>\MyLocalNugetSource

  • On Linux, *BSD, etc., ~/MyLocalNugetSource

This path is referred to later as <my_local_source>.

After picking a directory, run this .NET CLI command to configure NuGet to use your local source:

dotnet nuget add source <my_local_source> --name MyLocalNugetSource

When you run the build_assemblies.py script, pass <my_local_source> to the --push-nupkgs-local option:

./modules/mono/build_scripts/build_assemblies.py --godot-output-dir ./bin --push-nupkgs-local <my_local_source>

This option ensures the packages will be added to the specified local NuGet source and that conflicting versions of the package are removed from the NuGet cache. It's recommended to always use this option when building the C# solutions during development to avoid mistakes.

Building without depending on deprecated features (NO_DEPRECATED)

When building Redot without deprecated classes and functions, i.e. the deprecated=no argument for scons, the managed libraries must also be built without dependencies to deprecated code. This is done by passing the --no-deprecated argument:

::

./modules/mono/build_scripts/build_assemblies.py --godot-output-dir ./bin --push-nupkgs-local <my_local_source> --no-deprecated

Double Precision Support (REAL_T_IS_DOUBLE)

When building Redot with double precision support, i.e. the precision=double argument for scons, the managed libraries must be adjusted to match by passing the --precision=double argument:

./modules/mono/build_scripts/build_assemblies.py --godot-output-dir ./bin --push-nupkgs-local <my_local_source> --precision=double

Examples

Example (Windows)

# Build editor binary
scons platform=windows target=editor module_mono_enabled=yes
# Build export templates
scons platform=windows target=template_debug module_mono_enabled=yes
scons platform=windows target=template_release module_mono_enabled=yes

# Generate glue sources
bin/godot.windows.editor.x86_64.mono --headless --generate-mono-glue modules/mono/glue
# Build .NET assemblies
./modules/mono/build_scripts/build_assemblies.py --godot-output-dir=./bin --godot-platform=windows

Example (Linux, *BSD)

# Build editor binary
scons platform=linuxbsd target=editor module_mono_enabled=yes
# Build export templates
scons platform=linuxbsd target=template_debug module_mono_enabled=yes
scons platform=linuxbsd target=template_release module_mono_enabled=yes

# Generate glue sources
bin/godot.linuxbsd.editor.x86_64.mono --headless --generate-mono-glue modules/mono/glue
# Generate binaries
./modules/mono/build_scripts/build_assemblies.py --godot-output-dir=./bin --godot-platform=linuxbsd

Data directory

The data directory is a dependency for Redot binaries built with the .NET module enabled. It contains important files for the correct functioning of Redot. It must be distributed together with the Redot executable.

Editor

The name of the data directory for the Redot editor will always be GodotSharp. This directory contains an Api subdirectory with the Redot API assemblies and a Tools subdirectory with the tools required by the editor, like the GodotTools assemblies and its dependencies.

On macOS, if the Redot editor is distributed as a bundle, the GodotSharp directory may be placed in the <bundle_name>.app/Contents/Resources/ directory inside the bundle.

Export templates

The data directory for exported projects is generated by the editor during the export. It is named data_<APPNAME>_<ARCH>, where <APPNAME> is the application name as specified in the project setting application/config/name and <ARCH> is the current architecture of the export.

In the case of multi-architecture exports multiple such data directories will be generated.

Command-line options

The following is the list of command-line options available when building with the .NET module:

  • module_mono_enabled=yes | no

    • Build Redot with the .NET module enabled.