[codeblocks] for Keep only the [CSharp] part.
[param] is changed to <c>.
[b] for bold text.
[i] for italic text.
4.0 now uses variant, so [variant] to <see cref="Godot.Variant"/>.
since Rider does not support [u], only comments have been modified.
* Remove unused `EditorPropertyMember` and related hints, previouly used by
VisualScript. Such logic should be implemented in the VS module itself.
* As the above broke compatibility with the VS module, clean up the other
hacks that were still in core in support of VisualScript.
* `PROPERTY_USAGE_INTERNATIONALIZED` was only used in Object's
`get_translatable_strings()`, which is a legacy function not used anywhere.
So both are removed.
* Reordered some usage flags after the above removal to minimize the diff.
* General clean up.
Fixes#30203.
Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.
It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).
We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).
Also fixed "cf." Frenchism - it's meant as "refer to / see".
- Avoid generic types in `ScriptPathAttributeGenerator`, this
means they won't be added to the `[AssemblyHasScripts]` attribute
and a `[ScriptPath]` attribute won't be added to the class.
Since generic classes can't be used as scripts they shouldn't use
those attributes, this also makes CSharpScript consider those types
invalid since they won't be added to the script/type map.
- Avoid generic types in `ScriptManagerBridge.LookupScriptsInAssembly`.
- Set `outMethodsDest` in `ScriptManagerBridge.UpdateScriptClassInfo`.
- Renamed `ConvertToX` to `ConvertToNativeX`.
- Renamed `ConvertToXObject` to `ConvertToX`.
- Renamed `ConvertToXManaged` to `ConvertToX`.
- Fix `Signal` name in bindings generator and csharp script.
ReadOnly properties are currently not allowed because the generated code
needs to set them, this also apply to `init` properties because they
need to be set after initialization.
This was a regression from 17b2838f39.
`MarshalUtils` was changed in the source generators to use
`ConvertTo<T>` and `CreateFrom<T>`, which don't support `GodotObject[]`
because it would need reflection.
As such, we need to keep the custom cases for `GodotObject[]` in
`MarshalUtils`.
This change aims to reduce the number of places that need to be changed
when adding or editing a Godot type to the bindings.
Since the addition of `Variant.From<T>/As<T>` and
`VariantUtils.CreateFrom<T>/ConvertTo<T>`, we can now replace a lot of
the previous code in the bindings generator and the source generators
that specify these conversions for each type manually.
The only exceptions are the generic Godot collections (`Array<T>` and
`Dictionary<TKey, TValue>`) which still use the old version, as that
one cannot be matched by our new conversion methods (limitation in the
language with generics, forcing us to use delegate pointers).
The cleanup applies to:
- Bindings generator:
- `TypeInterface.cs_variant_to_managed`
- `TypeInterface.cs_managed_to_variant`
- Source generators:
- `MarshalUtils.AppendNativeVariantToManagedExpr`
- `MarshalUtils.AppendManagedToNativeVariantExpr`
- `MarshalUtils.AppendVariantToManagedExpr`
- `MarshalUtils.AppendManagedToVariantExpr`
This commit replaces most usages of `ConvertManagedObjectToVariant` and
`ConvertVariantToManagedObjectOfType`, by using the `Godot.Variant`
struct instead of `System.Object`.
The most notable change is to the `GetGodotPropertyDefaultValues` method
that's generated for scripts. The dictionary it returns now stores
`Godot.Variant` values.
Remaining usages are:
- The `DelegateUtils` class, for the serialization of closure display
classes during assembly reloading by the editor. These display classes
are compiler generated classes to store values captured by a closure.
Since it's generated by the compiler, the only way we have to access
the fields is through reflection. This leads to using `System.Object`.
- Converting parameters when invoking constructors from the engine.
This will be replaced with source generators in the future.
- Legacy support for old `GetGodotPropertyDefaultValues` return values.
We need to keep supporting the old version of this generated method
for some time. Otherwise, if loading a project built with the previous
version, it could lead to the loss of exported property values.
Ideally, we should remove this legacy support before a stable release.
- Remove `VariantSpanDisposer`, no need to dispose of the Variant Spans
since we are now borrowing the Variants instead of copying them.
- Remove `VariantSpanExtensions.Cleared` that was only used so the
Span was initialized for `VariantSpanDisposer` to know what to dispose.
- Fix stackalloc Spans to use constant VarArgsSpanThreshold
and avoid bound checks.
These callbacks are used for marshaling by callables and generic Godot
collections.
C# generics don't support specialization the way C++ templates do.
I knew NativeAOT could optimize away many type checks when the types
are known at compile time, but I didn't trust the JIT would do as good
a job, so I initially went with cached function pointers.
Well, it turns out the JIT is also very good at optimizing in this
scenario, so I'm changing the methods to do the conversion directly,
rather than returning a function pointer for the conversion.
The methods were moved to `VariantUtils`, and were renamed from
`GetFromVariantCallback/GetToVariantCallback` to `ConvertTo/CreateFrom`.
The new implementation looks like it goes through many `if` checks
at runtime to find the right branch for the type, but in practice it
works pretty much like template specialization. The JIT only generates
code for the relevant branch. Together with inlining, the result is
very close or the same as doing the conversion manually:
```cs
godot_variant variant;
int foo = variant.Int;
int bar = VariantUtils.ConvertTo<int>(variant);
```
If the type is a generic Godot collection, the conversion still goes
through a function pointer call.
The new code happens to be much shorter as well, with the file going
from 1057 lines to 407.
Side note: `Variant.cs` was mistakenly created in the wrong folder,
so I moved it to the `Core` folder.
We aim to make the C# API reflection-free, mainly for concerns about
performance, and to be able to target NativeAOT in refletion-free mode,
which reduces the binary size.
One of the main usages of reflection still left was the dynamic
invokation of callable delegates, and for some time I wasn't sure
I would find an alternative solution that I'd be happy with.
The new solution uses trampoline functions to invoke the delegates:
```
static void Trampoline(object delegateObj, NativeVariantPtrArgs args, out godot_variant ret)
{
if (args.Count != 1)
throw new ArgumentException($"Callable expected 1 arguments but received {args.Count}.");
string res = ((Func<int, string>)delegateObj)(
VariantConversionCallbacks.GetToManagedCallback<int>()(args[0])
);
ret = VariantConversionCallbacks.GetToVariantCallback<string>()(res);
}
Callable.CreateWithUnsafeTrampoline((int num) => "Foo" + num, &Trampoline);
```
Of course, this is too much boilerplate for user code. To improve this,
the `Callable.From` methods were added. These are overloads that take
`Action` and `Func` delegates, which covers the most common use cases:
lambdas and method groups:
```
// Lambda
Callable.From((int num) => "Foo" + num);
// Method group
string AppendNum(int num) => "Foo" + num;
Callable.From(AppendNum);
```
Unfortunately, due to limitations in the C# language, implicit
conversions from delegates to `Callable` are not supported.
`Callable.From` does not support custom delegates. These should be
uncommon, but the Godot C# API actually uses them for event signals.
As such, the bindings generator was updated to generate trampoline
functions for event signals. It was also optimized to use `Action`
instead of a custom delegate for parameterless signals, which removes
the need for the trampoline functions for those signals.
The change to reflection-free invokation removes one of the last needs
for `ConvertVariantToManagedObjectOfType`. The only remaining usage is
from calling script constructors with parameters from the engine
(`CreateManagedForGodotObjectScriptInstance`). Once that one is made
reflection-free, `ConvertVariantToManagedObjectOfType` can be removed.
- Creates a `Godot.Offline.Config` file to configurate NuGet with
Godot's fallback folder. This is easier because now we can assume we can
override the entire file since user config will likely be in the default
`NuGet.Config` file or an additional `*.config` file.
- Ensure the NuGet fallback folder is created at the same time it is
added to the NuGet configuration so future builds don't fail.
- Add `GodotSharp` and `GodotSharpEditor` packages to the fallback folder.
- Add `.nupkg.metadata` file to packages in fallback folder.
- Refer to `Godot.SourceGenerators` using the specific non-floating version
since floating versions don't seem to work with fallbackPackageFolders.
We want to replace libnethost as it gives us issues with some compilers.
Our implementation tries to mimic libnethost's hostfxr_resolver search
logic. We try to use the same function names for easier comparing in
case we need to update this in the future.
When the C# bindings generator finds a type without meta assume the type
refers to the 64-bit version of the type:
- `float` is converted to `double`
- `int` is converted to `long`
- Fix platform detection after Linux OS name was renamed from `LinuxBSD`
to `Linux`
- Fix arch detection after renaming `64` to `x86_64`
- Fix typo in `find_hostfxr`
- Replace `IndexOutOfRangeException` with `ArgumentOutOfRangeException`
- Replace `Exception` with a more specific exception
- Add the parameter name to argument exception
- Update documentation for methods that throw exceptions
- Use `StringBuilder` to build exception messages
- Ensure exception messages end with a period
- Remove event as a valid target of `SignalAttribute`
- Stop adding the `[Signal]` attribute to events in bindings_generator
- Make bindings_generator use the `EventHandler` suffix to be consistent with the C# source generator
- Remove obsolete comment about the signal's delegate name
- MustBeVariant attribute can be used to enforce that generic types must
be a marshable from/to Variant.
- Also renames all diagnostic ids to be valid unicode identifiers.
- In cases where both `Xform`/`XformInv` and the `*` operator were
implemented the `Xform`/`XformInv` methods were removed in favor of the
`*` operator.
- In cases where the `Xform`/`XformInv` existed but not the `*` operator,
the `Xform`/`XformInv` methods were replaced with the `*` operator.
- In cases where no method existed, a new `*` operator has been
implemented to support the same operations that are supported in GDScript.
- Fixes the `Transform.Xform` and `Transform.XformInv` with `Rect2`
implementation to use a zero `Rect2` size to start expanding from
(which is how it's implemented in C++).
- Moves interop functions to UnmanagedCallbacks struct that
contains the function pointers and is passed to C#.
- Implements UnmanagedCallbacksGenerator, a C# source generator that
generates the UnmanagedCallbacks struct in C# and the body for the
NativeFuncs methods (their implementation just calls the function
pointer in the UnmanagedCallbacks). The generated methods are needed
because .NET pins byref parameters of native calls, even if they are
'ref struct's, which don't need pinning. The generated methods use
`Unsafe.AsPointer` so that we can benefit from byref parameters
without suffering overhead of pinning.
Co-authored-by: Raul Santos <raulsntos@gmail.com>
The setting is initially assigned the name of the Godot project,
but it's kept freezed to prevent issues when renaming the Godot
project.
The user can always rename the C# project and solution manually and
change the setting to the new name.
This new version does not support the following type arguments:
- Generic types
- Array of Godot Object (Godot.Object[]) or derived types
The new implementation uses delegate pointers to call the Variant
conversion methods. We do type checking only once in the static
constructor to get the conversion delegates.
Now, we no longer need to do type checking every time, and we no
longer have to box value types.
This is the best implementation I could come up with, as C# generics
don't support anything similar to C++ template specializations.
- Array and Dictionary now store `Variant` instead of `System.Object`.
- Removed generic Array and Dictionary.
They cause too much issues, heavily relying on reflection and
very limited by the lack of a generic specialization.
- Removed support for non-Godot collections.
Support for them also relied heavily on reflection for marshaling.
Support for them will likely be re-introduced in the future, but
it will have to rely on source generators instead of reflection.
- Reduced our use of reflection.
The remaining usages will be moved to source generators soon.
The only usage that I'm not sure yet how to replace is dynamic
invocation of delegates.
Changed the signal declaration signal to:
```
// The following generates a MySignal event
[Signal] public delegate void MySignalEventHandler(int param);
```
In the past, the Godot editor distributed the API assemblies and
copied them to project directories for projects to reference them.
This changed with the move to .NET 5/6. Godot no longer copies the
assemblies to project directories. However, the project Sdk still
tried to reference them from the same location.
From now on, the GodotSharp API is distributed as a NuGet package,
which the Sdk can reference.
Added an option to `build_assemblies.py` to copy all Godot NuGet
packages to an existing local NuGet source. This will be needed
during development, while packages are not published to a remote
NuGet repository.
This option also makes sure to remove packages of the same version
installed (~/.nuget/packages). Very useful during development, when
packages change, to make sure the package being used by a project is
the same we just built and not one from a previous build.
A local NuGet source can be created like this:
```
mkdir ~/MyLocalNuGetSource && \
dotnet nuget add source ~/MyLocalNuGetSource/ -n MyLocalNuGetSource
```
Previously, we added source generators for invoking/accessing methods,
properties and fields in scripts. This freed us from the overhead of
reflection. However, the generated code still used our dynamic
marshaling functions, which do runtime type checking and box value
types.
This commit changes the bindings and source generators to include
'static' marshaling. Based on the types known at compile time, now
we generate the appropriate marshaling call for each type.
The editor no longer needs to create temporary instances to get the
default values. The initializer values of the exported properties are
still evaluated at runtime. For example, in the following example,
`GetInitialValue()` will be called when first looks for default values:
```
[Export] int MyValue = GetInitialValue();
```
Exporting fields with a non-supported type now results in a compiler
error rather than a runtime error when the script is used.
This base implementation is still very barebones but it defines the path
for how exporting will work (at least when embedding the .NET runtime).
Many manual steps are still needed, which should be automatized in the
future. For example, in addition to the API assemblies, now you also
need to copy the GodotPlugins assembly to each game project.
Finalizers are longer guaranteed to be called on exit now that
we switched to .NET Core. This results in native instances leaking.
The only solution I can think of so far is to keep a list of all
instances alive to dispose when the AssemblyLoadContext.Unloading
event is raised.
This replaces the way we invoke methods and set/get properties.
This first iteration rids us of runtime type checking in those
cases, as it's now done at compile time.
Later it will also stop needing the use of reflection. After that,
we will only depend on reflection for generic Godot Array and
Dictionary. We're stuck with reflection in generic collections
for now as C# doesn't support generic/template specialization.
This is only the initial implementation. Further iterations are
coming, specially once we switch to the native extension system
which completely changes the way members are accessed/invoked.
For example, with the native extension system we will likely need
to create `UnmanagedCallersOnly` invoke wrapper methods and return
function pointers to the engine.
Other kind of members, like event signals will be receiving the
same treatment in the future.
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.
The main focus here was to remove the majority of code that relied on
Mono's embedding APIs, specially the reflection APIs. The embedding
APIs we still use are the bare minimum we need for things to work.
A lot of code was moved to C#. We no longer deal with any managed
objects (`MonoObject*`, and such) in native code, and all marshaling
is done in C#.
The reason for restructuring the code and move away from embedding APIs
is that once we move to .NET Core, we will be limited by the much more
minimal .NET hosting.
PERFORMANCE REGRESSIONS
-----------------------
Some parts of the code were written with little to no concern about
performance. This includes code that calls into script methods and
accesses script fields, properties and events.
The reason for this is that all of that will be moved to source
generators, so any work prior to that would be a waste of time.
DISABLED FEATURES
-----------------
Some code was removed as it no longer makes sense (or won't make sense
in the future).
Other parts were commented out with `#if 0`s and TODO warnings because
it doesn't make much sense to work on them yet as those parts will
change heavily when we switch to .NET Core but also when we start
introducing source generators.
As such, the following features were disabled temporarily:
- Assembly-reloading (will be done with ALCs in .NET Core).
- Properties/fields exports and script method listing (will be
handled by source generators in the future).
- Exception logging in the editor and stack info for errors.
- Exporting games.
- Building of C# projects. We no longer copy the Godot API assemblies
to the project directory, so MSBuild won't be able to find them. The
idea is to turn them into NuGet packages in the future, which could
also be obtained from local NuGet sources during development.
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.
`shader_uniform` is now consistenly used across both per-shader
and per-instance shader uniform methods. This makes methods easier
to find in the class reference when looking for them.
Implement built-in classes Vector4, Vector4i and Projection.
* Two versions of Vector4 (float and integer).
* A Projection class, which is a 4x4 matrix specialized in projection types.
These types have been requested for a long time, but given they were very corner case they were not added before.
Because in Godot 4, reimplementing parts of the rendering engine is now possible, access to these types (heavily used by the rendering code) becomes a necessity.
**Q**: Why Projection and not Matrix4?
**A**: Godot does not use Matrix2, Matrix3, Matrix4x3, etc. naming convention because, within the engine, these types always have a *purpose*. As such, Godot names them: Transform2D, Transform3D or Basis. In this case, this 4x4 matrix is _always_ used as a _Projection_, hence the naming.
Adds support for generating C# bindings that use the generic `Array<T>`
type instead of the non-generic `Array` type when the registered ClassDB
method specifies the array element type.
* Map is unnecessary and inefficient in almost every case.
* Replaced by the new HashMap.
* Renamed Map to RBMap and Set to RBSet for cases that still make sense
(order matters) but use is discouraged.
There were very few cases where replacing by HashMap was undesired because
keeping the key order was intended.
I tried to keep those (as RBMap) as much as possible, but might have missed
some. Review appreciated!
Adds a new, cleaned up, HashMap implementation.
* Uses Robin Hood Hashing (https://en.wikipedia.org/wiki/Hash_table#Robin_Hood_hashing).
* Keeps elements in a double linked list for simpler, ordered, iteration.
* Allows keeping iterators for later use in removal (Unlike Map<>, it does not do much
for performance vs keeping the key, but helps replace old code).
* Uses a more modern C++ iterator API, deprecates the old one.
* Supports custom allocator (in case there is a wish to use a paged one).
This class aims to unify all the associative template usage and replace it by this one:
* Map<> (whereas key order does not matter, which is 99% of cases)
* HashMap<>
* OrderedHashMap<>
* OAHashMap<>
PhysicsServer3DExtension inherits from PhysicsServer3D which is a
singleton class, since singleton classes are generated as static in C#
it would generate invalid C# so for now we'll be
ignoring PhysicsServer3DExtension.
The specific `_append_xml_*` methods implement the logic that generates
the proper XML documentation for the given BBCode tag and target and
appends it to the output.
- Outputs errors for missing members or methods when generating the C#
documentation.
- Hardcodes a special case for the `_init` method, in C# we'll reference
the constructor.
- Ignores properties with slashes (since they are not declared in C# and
can't be referenced in the documentation).
All iOS devices since the iPhone 5S support ARMv8 (64-bit).
The last iOS version supported on ARMv7 devices is 10.x, which is
too old to run Godot 4.0 projects since the minimum supported
iOS version is 11.0.
This fixes a conflict with the `pressed` signal.
The new name is temporary and only intended to solve the conflict for upcoming
alpha builds. Discussions are still ongoing regarding the BaseButton API and
how to rename and refactor more of its properties, signals and methods to have
a clearer API in 4.0.
Bump `Godot.NET.Sdk` to version 4.0.0-dev6.
Bump `Godot.SourceGenerators` to version 4.0.0-dev3.
Use floating version 4.0.*-* for package references in Sdk.
We prefer to prevent using chained assignment (`T a = b = c = T();`) as this
can lead to confusing code and subtle bugs.
According to https://en.wikipedia.org/wiki/Assignment_operator_(C%2B%2B), C++
allows any arbitrary return type, so this is standard compliant.
This could be re-assessed if/when we have an actual need for a behavior more
akin to that of the C++ STL, for now this PR simply changes a handful of
cases which were inconsistent with the rest of the codebase (`void` return
type was already the most common case prior to this commit).
Sets `AlignOperands` to `DontAlign`.
`clang-format` developers seem to mostly care about space-based indentation and
every other version of clang-format breaks the bad mismatch of tabs and spaces
that it seems to use for operand alignment. So it's better without, so that it
respects our two-tabs `ContinuationIndentWidth`.
Apply suggestions from code review
Merging @akien-mga's suggestion with the matching change to the CS project
Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>
Use `System.Array.Empty<T>` to get an empty array instead of allocating
a new one every time. Since arrays are immutable there is no need to
allocate them every time.
* Added a new macro SNAME() that constructs and caches a local stringname.
* Subsequent usages use the cached version.
* Since these use a global static variable, a second refcounter of static usages need to be kept for cleanup time.
* Replaced all theme usages by this new macro.
* Replace all signal emission usages by this new macro.
* Replace all call_deferred usages by this new macro.
This is part of ongoing work to optimize GUI and the editor.
While there are still various bugs to solve and features to implement, the C#
support as of Godot 3.4 is fairly mature and already used by a number of users
in production. Now that we default to dotnet CLI as build tool, it also seems
to be more reliable than MSBuild.
The documentation can (and does for the most part) point out some caveats that
users should be aware of, but this info dialog has outlived its intended
purpose.
- Fix C++ compile errors about pending variable renames after the `Reference` to `RefCount` change.
- Fix C# compile errors due to the recent rename of `EnablePlugin()` and `Build()`, which are now underscore-prefixed in bindings.
- Additional rename: `godot_icall_Reference_Dtor` to `godot_icall_RefCounted_Dtor`.
The order of numbers is not changed except for Transform2D. All logic is done inside of their structures (and not in Variant).
For the number of decimals printed, they now use String::num_real which works best with real_t, except for Color which is fixed at 4 decimals (this is a reliable number of float digits when converting from 16-bpc so it seems like a good choice)
The following two bugs were fixed:
- For classes without namespace we were still generating `namespace {`
without a namespace identifier, causing a syntax error.
- For classes with nested namespaces we were generating only the innermost
part of the namespace was being generated, e.g.: for `Foo.Bar` we were
generating `namespace Bar {` instead of `namespace Foo.Bar {`.
This wasn't causing any build error, but because of the wrong namespace
Godot wasn't able to find the class associated with the script.
This source generator adds a newly introduced attribute,
`ScriptPath` to all classes that:
- Are top-level classes (not inner/nested).
- Have the `partial` modifier.
- Inherit `Godot.Object`.
- The class name matches the file name.
A build error is thrown if the generator finds a class that meets these
conditions but is not declared `partial`, unless the class is annotated
with the `DisableGodotGenerators` attribute.
We also generate an `AssemblyHasScripts` assembly attribute which Godot
uses to get all the script classes in the assembly, eliminating the need
for Godot to search them. We can also avoid searching in assemblies that
don't have this attribute. This will be good for performance in the
future once we support multiple assemblies with Godot script classes.
This is an example of what the generated code looks like:
```
using Godot;
namespace Foo {
[ScriptPathAttribute("res://Player.cs")]
// Multiple partial declarations are allowed
[ScriptPathAttribute("res://Foo/Player.cs")]
partial class Player {}
}
[assembly:AssemblyHasScripts(new System.Type[] { typeof(Foo.Player) })]
```
The new attributes replace script metadata which we were generating by
determining the namespace of script classes with a very simple parser.
This fixes several issues with the old approach related to parser
errors and conditional compilation.
It also makes the task part of the MSBuild project build, rather than
a separate step executed by the Godot editor.
