Godot.NET.Sdk
-------------
Godot uses its own custom MSBuild Sdk for game
projects. This new Sdk adds its own functionality
on top of 'Microsoft.NET.Sdk'.
The new Sdk is resolved from the NuGet package.
All the default boilerplate was moved from game
projects to the Sdk. The default csproj for
game project can now be as simple as:
```
<Project Sdk="Godot.NET.Sdk/4.0.0-dev2">
<PropertyGroup>
<TargetFramework>netstandard2.1</TargetFramework>
</PropertyGroup>
</Project>
```
Source files are included by automatically so
Godot no longer needs to keep the csproj in sync
when creating new source files.
Define constants
----------------
Godot defines a list of constants for conditional
compilation. When exporting games, this list also
included engine 'features' and platform 'bits'.
There were a few problems with that:
- The 'features' constants were only defined when
exporting games. Not when building the game for
running in the editor player.
- If the project was built externally by an IDE,
the constants wouldn't be defined at all.
The new Sdk assigns default values to these
constants when not built from the Godot editor,
i.e.: when built from an IDE or from the command
line. The default define constants are determined
from the system MSBuild is running on.
However, it's not possible for MSBuild to
determine the set of supported engine features.
It's also not possible to determine if a project
is being built to run on a 32-bit or 64-bit
Godot executable.
As such the 'features' and 'bits' constants had
to be removed.
The benefit of checking those at compile time
was questionable, and they can still be checked
at runtime.
The new list of define constants includes:
- GODOT
- GODOT_<PLATFORM>
Defaults to the platform MSBuild is running on.
- GODOT_<PC/MOBILE/WEB>
- TOOLS
When building with the 'Debug' configuration
(editor and editor player).
- GODOT_REAL_T_IS_DOUBLE
Not defined by default unless $(GodotRealTIsDouble)
is overriden to be 'true'.
.NET Standard
-------------
The target framework of game projects was changed
to 'netstandard2.1'.
By adding a reference to the 'Microsoft.NETFramework.ReferenceAssemblies' nuget
package, we can build projects targeting .NET Framework with the dotnet CLI.
By referencing this package we also don't need to install Mono on Linux/macOS
or .NET Framework on Windows, as the assemblies are taken from the package.
Previously we had a placeholder solution called 'Managed' to benefit from
tooling while editing the a part of the C# API.
Later the bindings generator would create the final 'GodotSharp' solution
including these C# files as well as the auto-generated C# API.
Now we replaced the 'Managed' solution with the final 'GodotSharp' solution
which is no longer auto-generated, and the bindings generator only takes
care of the auto-generated C# API.
This has the following benefits:
- It's less confusing as there will no longer be two versions of the same file
(the original and a generated copy of it). Now there's only one.
- We no longer need placeholder for auto-generated API classes, like Node or
Resource. We used them for benefiting from tooling. Now we can just use the
auto-generated API itself.
- Simplifies the build system and bindings generator. Removed lot of code
that is not needed anymore.
Also added a post-build target to the GodotTools project to copy the output to
the data dir. This makes it easy to iterate when doing changes to GodotTools,
as SCons doesn't have to be executed anymore just to copy these new files.
