{ godot3, mono, scons, python311Packages, }: (godot3.override { scons = scons.override { python3Packages = python311Packages; }; }).overrideAttrs ( self: base: { pname = "godot3-mono-glue"; godotBuildDescription = "mono glue"; godotBuildPlatform = "server"; sconsFlags = base.sconsFlags ++ [ "module_mono_enabled=true" "mono_glue=false" # Indicates not to expect already existing glue. "mono_prefix=${mono}" ]; nativeBuildInputs = base.nativeBuildInputs ++ [ mono ]; patches = base.patches ++ map (rp: ./patches + rp) ([ # When building godot mono, a "glue version" gets baked into it, and into the mono glue code # generated by it. Godot mono export templates are also get a glue version baked in. If you # export a godot mono project using an export template for which the glue version doesn't # match that of the godot mono tool itself, then the resulting game will fail with an error # saying "The assembly 'GodotSharp' is out of sync." Thus, if we want our build of godot mono # to be compatible with the official export templates, we need to ensure it is built with the # same glue version as the official build. # # A python script in the godot source, i.e. modules/mono/build_scripts/gen_cs_glue_version.py, # is used by the build process to generate the glue version number. The official version of it # does so based on the latest modified time of all the C# files in the GodotSharp solution. This # is problematic because it is difficult to reproduce the exact timestamps that the files had # when the official build was created. This is further complicated by the fact that nix clears # the timestamps on the source files when they're unpacked. Thus, we can't simply regenerate the # official glue version by building from the official source. # # To address this, we are patching the python script with a hard-coded glue version number. This # patch file needs to be updated for every new version of godot, so to enforce this, the godot # version is baked in to the file name, causing the build to fail until the patch is updated. # # The correct glue version number for a given godot version is obtained by running the official # build of that version of godot with the --generate-mono-glue flag. This generates the mono # glue files. One of those files, mono_glue.gen.cpp, has a function called get_cs_glue_version() # which contains a hard-coded number. This is the glue version to put in the patch file. # # For convenience, the accompanying update-glue-version.sh script automates this work. Run it by # passing the godot version as an argument, e.g. "3.5.2". "/gen_cs_glue_version.py/hardcodeGlueVersion_${self.version}.patch" ]); outputs = [ "out" ]; installPhase = '' runHook preInstall glue="$out"/modules/mono/glue mkdir -p "$glue" bin/godot_server.x11.opt.tools.*.mono --generate-mono-glue "$glue" runHook postInstall ''; meta = base.meta // { homepage = "https://docs.godotengine.org/en/stable/development/compiling/compiling_with_mono.html#generate-the-glue"; }; } )