We're targeting .NET 5 for now to make development easier while
.NET 6 is not yet released.
TEMPORARY REGRESSIONS
---------------------
Assembly unloading is not implemented yet. As such, many Godot
resources are leaked at exit. This will be re-implemented later
together with assembly hot-reloading.
We will be progressively moving most code to C#.
The plan is to only use Mono's embedding APIs to set things at launch.
This will make it much easier to later support CoreCLR too which
doesn't have rich embedding APIs.
Additionally the code in C# is more maintainable and makes it easier
to implement new features, e.g.: runtime codegen which we could use to
avoid using reflection for marshaling everytime a field, property or
method is accessed.
SOME NOTES ON INTEROP
We make the same assumptions as GDNative about the size of the Godot
structures we use. We take it a bit further by also assuming the layout
of fields in some cases, which is riskier but let's us squeeze out some
performance by avoiding unnecessary managed to native calls.
Code that deals with native structs is less safe than before as there's
no RAII and copy constructors in C#. It's like using the GDNative C API
directly. One has to take special care to free values they own.
Perhaps we could use roslyn analyzers to check this, but I don't know
any that uses attributes to determine what's owned or borrowed.
As to why we maily use pointers for native structs instead of ref/out:
- AFAIK (and confirmed with a benchmark) ref/out are pinned
during P/Invoke calls and that has a cost.
- Native struct fields can't be ref/out in the first place.
- A `using` local can't be passed as ref/out, only `in`. Calling a
method or property on an `in` value makes a silent copy, so we want
to avoid `in`.
REGARDING THE BUILD SYSTEM
There's no longer a `mono_glue=yes/no` SCons options. We no longer
need to build with `mono_glue=no`, generate the glue and then build
again with `mono_glue=yes`. We build only once and generate the glue
(which is in C# now).
However, SCons no longer builds the C# projects for us. Instead one
must run `build_assemblies.py`, e.g.:
```sh
%godot_src_root%/modules/mono/build_scripts/build_assemblies.py \
--godot-output-dir=%godot_src_root%/bin \
--godot-target=release_debug`
```
We could turn this into a custom build target, but I don't know how
to do that with SCons (it's possible with Meson).
OTHER NOTES
Most of the moved code doesn't follow the C# naming convention and
still has the word Mono in the names despite no longer dealing with
Mono's embedding APIs. This is just temporary while transitioning,
to make it easier to understand what was moved where.
Makes it let's bothersome to work with builds from our
godotengine/godot-mono-builds scripts, as they write the
BCL into an output directory separate from the runtime
(which is good as two runtimes may share the same BCL).
ptrcall is now also used to optimize calls in GDScript, on top of the existing
use by the GDNative and Mono modules.
It no longer makes sense to make it optional.
Right now, games only work on devices when exported with FullAOT+Interpreter.
There are some issues left that need to addressed for FullAOT alone. Right now,
it's giving issues with the Godot.NativeCalls static constructor.
Configured for a max line length of 120 characters.
psf/black is very opinionated and purposely doesn't leave much room for
configuration. The output is mostly OK so that should be fine for us,
but some things worth noting:
- Manually wrapped strings will be reflowed, so by using a line length
of 120 for the sake of preserving readability for our long command
calls, it also means that some manually wrapped strings are back on
the same line and should be manually merged again.
- Code generators using string concatenation extensively look awful,
since black puts each operand on a single line. We need to refactor
these generators to use more pythonic string formatting, for which
many options are available (`%`, `format` or f-strings).
- CI checks and a pre-commit hook will be added to ensure that future
buildsystem changes are well-formatted.
- Travis: Change x11 to linuxbsd
- SCons: Change x11 plataform to linuxbsd
- Plugins: Remove ; to avoid fallthrough warning
- DisplayServerX11: Implement set_icon
- DisplayServerX11: Fix X11 bug when a window was erased from windows
map, all the changes from that erased windows are sending to the main
window
- DisplayServerX11: Reorder create_window commands
- DisplayServerX11: Change every Size2 to Size2i and Rect2 to Rect2i
where it belongs
+ More X11 fixes which have been integrated directly back into reduz's
original commits while rebasing the branch.
- Bundle editor dependencies:
- 'GodotSharp': Root data directory for the editor
- 'Tools': Editor dependencies. Only GodotSharp.dll for now.
- 'Api': Prebuilt GodotSharp and GodotSharpEditor API assemblies.
- 'Mono': Mono files to bundle with the editor.
- 'bin': (Optional, not used for now) Mono bin directory.
- 'etc': Mono configuration files.
- 'lib': Mono dependency shared libraries.
- 'lib/mono/4.5': Framework assemblies.
- Added build option to copy the required files from the mono installation to 'GodotSharp/Mono'. Enable with 'copy_mono_root=yes'. Disabled by default.
- Export template dependencies:
- 'data_AppName'/'data_Godot':
- 'Mono': Mono files to bundle with the game.
- 'etc': Mono configuration files.
- 'lib': Mono dependency shared libraries.
- The data directory is generated when compiling and must be bundled with the export templates. In the case of OSX, the data directory must be placed inside the 'osx.zip' export template.
- In OSX, alternative location for directories (needed for app bundles) are:
- 'data_AppName/Mono/etc' --> '../Resources/GodotSharp/Mono/etc'
- 'data_AppName/Mono/lib' --> '../Frameworks/GodotSharp/Mono/lib'
- The editor can bundle prebuilt API assemblies.
- Generate them with a tools build by running: `--generate-cs-core-api <GodotSharp_OutputDir> --generate-cs-editor-api <GodotSharpEditor_OutputDir> <GodotSharp_OutputDir>/bin/Release/GodotSharp.dll` (This command will be simplified in the future and both projects will be in the same solution)
- Build the solutions and copy the output files to '#bin/GodotSharp/Api'.
- Fixed API assembly being added twice during the export process.
This enhancement is specially noticeable in OSX, since it includes Mono's install location (both official and homebrew). This makes it possible to build Godot with Mono on OSX without pkg-config (pkg-config is bundled with Mono, but it's not added to PATH, so finding it would require finding the Mono root directory first).
- Add (Csc/Vbc/Fsc)ToolExe environment variables when running Mono's MSBuild.
- Fix directory for the 'mono_assemblies_output_dir' argument being created with the '#' top level directory token as part of its name.
- Allow to build with 'mono_static=yes' on Unix without specifying a mono prefix. The build script will try to find the mono prefix using the output from pkg-config.
- Bundle with mscorlib.dll to avoid compatibilities issues
- Add build option 'mono_assemblies_output_dir' to specify the output directory where the assemblies will be copied to. '#bin' by default.
- Make sure to search the mono installation directory for the right architecture in the windows registry.
- Do not build GodotSharpTools directly to #bin dir. Instead build to the default output path and copy it. This way we avoid MSBuild adding files we don't want to #bin.
- Add hint path for MSBuild in OSX.
- Copy shared library on Unix if not statically linking.
- Use vswhere to search MSBuild and search for 14.0 tools version in the registry instead of 4.0.
- SCons will only fallback xbuild when msbuild is not found if 'xbuild_fallback=yes' is passed to the command.
- Use mono's assembly path as FrameworkPathOverride if using with system's MSBuild (not mono's fork).
- Cleanup.
