# Objective
Using `Reflect::clone_value` can be somewhat confusing to those
unfamiliar with how Bevy's reflection crate works. For example take the
following code:
```rust
let value: usize = 123;
let clone: Box<dyn Reflect> = value.clone_value();
```
What can we expect to be the underlying type of `clone`? If you guessed
`usize`, then you're correct! Let's try another:
```rust
#[derive(Reflect, Clone)]
struct Foo(usize);
let value: Foo = Foo(123);
let clone: Box<dyn Reflect> = value.clone_value();
```
What about this code? What is the underlying type of `clone`? If you
guessed `Foo`, unfortunately you'd be wrong. It's actually
`DynamicStruct`.
It's not obvious that the generated `Reflect` impl actually calls
`Struct::clone_dynamic` under the hood, which always returns
`DynamicStruct`.
There are already some efforts to make this a bit more apparent to the
end-user: #7207 changes the signature of `Reflect::clone_value` to
instead return `Box<dyn PartialReflect>`, signaling that we're
potentially returning a dynamic type.
But why _can't_ we return `Foo`?
`Foo` can obviously be cloned— in fact, we already derived `Clone` on
it. But even without the derive, this seems like something `Reflect`
should be able to handle. Almost all types that implement `Reflect`
either contain no data (trivially clonable), they contain a
`#[reflect_value]` type (which, by definition, must implement `Clone`),
or they contain another `Reflect` type (which recursively fall into one
of these three categories).
This PR aims to enable true reflection-based cloning where you get back
exactly the type that you think you do.
## Solution
Add a `Reflect::reflect_clone` method which returns `Result<Box<dyn
Reflect>, ReflectCloneError>`, where the `Box<dyn Reflect>` is
guaranteed to be the same type as `Self`.
```rust
#[derive(Reflect)]
struct Foo(usize);
let value: Foo = Foo(123);
let clone: Box<dyn Reflect> = value.reflect_clone().unwrap();
assert!(clone.is::<Foo>());
```
Notice that we didn't even need to derive `Clone` for this to work: it's
entirely powered via reflection!
Under the hood, the macro generates something like this:
```rust
fn reflect_clone(&self) -> Result<Box<dyn Reflect>, ReflectCloneError> {
Ok(Box::new(Self {
// The `reflect_clone` impl for `usize` just makes use of its `Clone` impl
0: Reflect::reflect_clone(&self.0)?.take().map_err(/* ... */)?,
}))
}
```
If we did derive `Clone`, we can tell `Reflect` to rely on that instead:
```rust
#[derive(Reflect, Clone)]
#[reflect(Clone)]
struct Foo(usize);
```
<details>
<summary>Generated Code</summary>
```rust
fn reflect_clone(&self) -> Result<Box<dyn Reflect>, ReflectCloneError> {
Ok(Box::new(Clone::clone(self)))
}
```
</details>
Or, we can specify our own cloning function:
```rust
#[derive(Reflect)]
#[reflect(Clone(incremental_clone))]
struct Foo(usize);
fn incremental_clone(value: &usize) -> usize {
*value + 1
}
```
<details>
<summary>Generated Code</summary>
```rust
fn reflect_clone(&self) -> Result<Box<dyn Reflect>, ReflectCloneError> {
Ok(Box::new(incremental_clone(self)))
}
```
</details>
Similarly, we can specify how fields should be cloned. This is important
for fields that are `#[reflect(ignore)]`'d as we otherwise have no way
to know how they should be cloned.
```rust
#[derive(Reflect)]
struct Foo {
#[reflect(ignore, clone)]
bar: usize,
#[reflect(ignore, clone = "incremental_clone")]
baz: usize,
}
fn incremental_clone(value: &usize) -> usize {
*value + 1
}
```
<details>
<summary>Generated Code</summary>
```rust
fn reflect_clone(&self) -> Result<Box<dyn Reflect>, ReflectCloneError> {
Ok(Box::new(Self {
bar: Clone::clone(&self.bar),
baz: incremental_clone(&self.baz),
}))
}
```
</details>
If we don't supply a `clone` attribute for an ignored field, then the
method will automatically return
`Err(ReflectCloneError::FieldNotClonable {/* ... */})`.
`Err` values "bubble up" to the caller. So if `Foo` contains `Bar` and
the `reflect_clone` method for `Bar` returns `Err`, then the
`reflect_clone` method for `Foo` also returns `Err`.
### Attribute Syntax
You might have noticed the differing syntax between the container
attribute and the field attribute.
This was purely done for consistency with the current attributes. There
are PRs aimed at improving this. #7317 aims at making the
"special-cased" attributes more in line with the field attributes
syntactically. And #9323 aims at moving away from the stringified paths
in favor of just raw function paths.
### Compatibility with Unique Reflect
This PR was designed with Unique Reflect (#7207) in mind. This method
actually wouldn't change that much (if at all) under Unique Reflect. It
would still exist on `Reflect` and it would still `Option<Box<dyn
Reflect>>`. In fact, Unique Reflect would only _improve_ the user's
understanding of what this method returns.
We may consider moving what's currently `Reflect::clone_value` to
`PartialReflect` and possibly renaming it to `partial_reflect_clone` or
`clone_dynamic` to better indicate how it differs from `reflect_clone`.
## Testing
You can test locally by running the following command:
```
cargo test --package bevy_reflect
```
---
## Changelog
- Added `Reflect::reflect_clone` method
- Added `ReflectCloneError` error enum
- Added `#[reflect(Clone)]` container attribute
- Added `#[reflect(clone)]` field attribute
This pr uses the `extern crate self as` trick to make proc macros behave
the same way inside and outside bevy.
# Objective
- Removes noise introduced by `crate as` in the whole bevy repo.
- Fixes#17004.
- Hardens proc macro path resolution.
## TODO
- [x] `BevyManifest` needs cleanup.
- [x] Cleanup remaining `crate as`.
- [x] Add proper integration tests to the ci.
## Notes
- `cargo-manifest-proc-macros` is written by me and based/inspired by
the old `BevyManifest` implementation and
[`bkchr/proc-macro-crate`](https://github.com/bkchr/proc-macro-crate).
- What do you think about the new integration test machinery I added to
the `ci`?
More and better integration tests can be added at a later stage.
The goal of these integration tests is to simulate an actual separate
crate that uses bevy. Ideally they would lightly touch all bevy crates.
## Testing
- Needs RA test
- Needs testing from other users
- Others need to run at least `cargo run -p ci integration-test` and
verify that they work.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Add reflection support to more `glam` `Vec` types, specifically
* I8Vec2
* I8Vec3
* I8Vec4
* U8Vec2
* U8Vec3
* U8Vec4
* I16Vec2
* I16Vec3
* I16Vec4
* U16Vec2
* U16Vec3
* U16Vec4
I needed to do this because I'm using various of these in my Bevy types,
and due to the orphan rules, I can't make these impls locally.
## Solution
Used `impl_reflect!` like for the existing types.
## Testing
This should not require additional testing, though I have verified that
reflection now works for these types in my own project.
# Objective
We want to deny the following lints:
* `clippy::allow_attributes` - Because there's no reason to
`#[allow(...)]` an attribute if it wouldn't lint against anything; you
should always use `#[expect(...)]`
* `clippy::allow_attributes_without_reason` - Because documenting the
reason for allowing/expecting a lint is always good
## Solution
Set the `clippy::allow_attributes` and
`clippy::allow_attributes_without_reason` lints to `deny`, and bring
`bevy_reflect` in line with the new restrictions.
No code changes have been made - except if a lint that was previously
`allow(...)`'d could be removed via small code changes. For example,
`unused_variables` can be handled by adding a `_` to the beginning of a
field's name.
## Testing
I ran `cargo clippy`, and received no errors.
# Background
In `no_std` compatible crates, there is often an `std` feature which
will allow access to the standard library. Currently, with the `std`
feature _enabled_, the
[`std::prelude`](https://doc.rust-lang.org/std/prelude/index.html) is
implicitly imported in all modules. With the feature _disabled_, instead
the [`core::prelude`](https://doc.rust-lang.org/core/prelude/index.html)
is implicitly imported. This creates a subtle and pervasive issue where
`alloc` items _may_ be implicitly included (if `std` is enabled), or
must be explicitly included (if `std` is not enabled).
# Objective
- Make the implicit imports for `no_std` crates consistent regardless of
what features are/not enabled.
## Solution
- Replace the `cfg_attr` "double negative" `no_std` attribute with
conditional compilation to _include_ `std` as an external crate.
```rust
// Before
#![cfg_attr(not(feature = "std"), no_std)]
// After
#![no_std]
#[cfg(feature = "std")]
extern crate std;
```
- Fix imports that are currently broken but are only now visible with
the above fix.
## Testing
- CI
## Notes
I had previously used the "double negative" version of `no_std` based on
general consensus that it was "cleaner" within the Rust embedded
community. However, this implicit prelude issue likely was considered
when forming this consensus. I believe the reason why is the items most
affected by this issue are provided by the `alloc` crate, which is
rarely used within embedded but extensively used within Bevy.
# Objective
- Resolve several warnings encountered when compiling for `no_std`
around `dead_code`
- Fix compatibility with `wasm32-unknown-unknown` when using `no_std`
(identified by Sachymetsu on
[Discord](https://discord.com/channels/691052431525675048/692572690833473578/1323365426901549097))
## Solution
- Removed some unused imports
- Added `allow(dead_code)` for certain private items when compiling on
`no_std`
- Fixed `bevy_app` and `bevy_tasks` compatibility with WASM when
compiling without `std` by appropriately importing `Box` and feature
gating panic unwinding
## Testing
- CI
# Objective
- Contributes to #15460
## Solution
- Added `std` feature (enabled by default)
## Testing
- CI
- `cargo check -p bevy_reflect --no-default-features --target
"x86_64-unknown-none"`
- UEFI demo application runs with this branch of `bevy_reflect`,
allowing `derive(Reflect)`
## Notes
- The [`spin`](https://crates.io/crates/spin) crate has been included to
provide `RwLock` and `Once` (as an alternative to `OnceLock`) when the
`std` feature is not enabled. Another alternative may be more desirable,
please provide feedback if you have a strong opinion here!
- Certain items (`Box`, `String`, `ToString`) provided by `alloc` have
been added to `__macro_exports` as a way to avoid `alloc` vs `std`
namespacing. I'm personally quite annoyed that we can't rely on `alloc`
as a crate name in `std` environments within macros. I'd love an
alternative to my approach here, but I suspect it's the least-bad
option.
- I would've liked to have an `alloc` feature (for allocation-free
`bevy_reflect`), unfortunately, `erased_serde` unconditionally requires
access to `Box`. Maybe one day we could design around this, but for now
it just means `bevy_reflect` requires `alloc`.
---------
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
#15349 added an `impl_reflect!` for `glam::EulerRot`. This was done by
copying and pasting the enum definition from `glam` into `bevy_reflect`
so that the macro could interpret the variants.
However, as mentioned in the description for that PR, this would need to
be updated for `glam` 0.29, as it had not been updated yet.
#15249 came and updated `glam` to 0.29, but did not change these impls.
This is understandable as failing to do so doesn't cause any compile
errors.
This PR updates the definition and aims to make this silent breakage a
little less silent.
## Solution
Firstly, I updated the definition for `EulerRot` to match the one from
`glam`.
Secondly, I added the `assert_type_match` crate, which I created
specifically to solve this problem. By using this crate, we'll get a
compile time error if `glam` ever decides to change `EulerRot` again.
In the future we can consider using it for other types with this
problem, including in other crates (I'm pretty sure `bevy_window` and/or
`bevy_winit` also copy+paste some types). I made sure to use as few
dependencies as possible so everything should already be in-tree (it's
just `quote`, `proc-macro2`, and `syn` with default features).
## Testing
No tests added. CI should pass.
---
## Migration Guide
The reflection implementation for `EulerRot` has been updated to align
with `glam` 0.29. Please update any reflection-based usages accordingly.
# Objective
Currently, the term "value" in the context of reflection is a bit
overloaded.
For one, it can be used synonymously with "data" or "variable". An
example sentence would be "this function takes a reflected value".
However, it is also used to refer to reflected types which are
`ReflectKind::Value`. These types are usually either primitives, opaque
types, or types that don't fall into any other `ReflectKind` (or perhaps
could, but don't due to some limitation/difficulty). An example sentence
would be "this function takes a reflected value type".
This makes it difficult to write good documentation or other learning
material without causing some amount of confusion to readers. Ideally,
we'd be able to move away from the `ReflectKind::Value` usage and come
up with a better term.
## Solution
This PR replaces the terminology of "value" with "opaque" across
`bevy_reflect`. This includes in documentation, type names, variant
names, and macros.
The term "opaque" was chosen because that's essentially how the type is
treated within the reflection API. In other words, its internal
structure is hidden. All we can do is work with the type itself.
### Primitives
While primitives are not technically opaque types, I think it's still
clearer to refer to them as "opaque" rather than keep the confusing
"value" terminology.
We could consider adding another concept for primitives (e.g.
`ReflectKind::Primitive`), but I'm not sure that provides a lot of
benefit right now. In most circumstances, they'll be treated just like
an opaque type. They would also likely use the same macro (or two copies
of the same macro but with different names).
## Testing
You can test locally by running:
```
cargo test --package bevy_reflect --all-features
```
---
## Migration Guide
The reflection concept of "value type" has been replaced with a clearer
"opaque type". The following renames have been made to account for this:
- `ReflectKind::Value` → `ReflectKind::Opaque`
- `ReflectRef::Value` → `ReflectRef::Opaque`
- `ReflectMut::Value` → `ReflectMut::Opaque`
- `ReflectOwned::Value` → `ReflectOwned::Opaque`
- `TypeInfo::Value` → `TypeInfo::Opaque`
- `ValueInfo` → `OpaqueInfo`
- `impl_reflect_value!` → `impl_reflect_opaque!`
- `impl_from_reflect_value!` → `impl_from_reflect_opaque!`
Additionally, declaring your own opaque types no longer uses
`#[reflect_value]`. This attribute has been replaced by
`#[reflect(opaque)]`:
```rust
// BEFORE
#[derive(Reflect)]
#[reflect_value(Default)]
struct MyOpaqueType(u32);
// AFTER
#[derive(Reflect)]
#[reflect(opaque)]
#[reflect(Default)]
struct MyOpaqueType(u32);
```
Note that the order in which `#[reflect(opaque)]` appears does not
matter.
# Objective
Currently, Bevy implements reflection for `glam::EulerRot` using:
```rs
impl_reflect_value!(::glam::EulerRot(Debug, Default, Deserialize, Serialize));
```
Treating it as an opaque type. However, it's useful to expose the
EulerRot enum variants directly, which I make use of from a drop down
selection box in `bevy_egui`. This PR changes this to use
`impl_reflect!`.
**Importantly**, Bevy currently uses glam 0.28.0, in which `EulerRot`
has just 6 variants. In glam 0.29.0, this is exanded to 24 variants, see
bb2ab05613.
When Bevy updates to 0.29.0, this reflect impl must also be updated to
include the new variants.
## Solution
Replaces the `impl_reflect_value!` with `impl_reflect!` and a
handwritten version of `EulerRot` with the same variants.
## Testing
Added a `tests` module to `glam.rs` to ensure that de/serialization
works. However, my main concern is making sure that the number of enum
variants matches glam's, which I'm not sure how to do using `Enum`.
# Objective
Fix#10284.
## Solution
When `DynamicSceneBuilder` extracts entities, they are cloned via
`PartialReflect::clone_value`, making them into dynamic versions of the
original components. This loses any custom `ReflectSerialize` type data.
Dynamic scenes are deserialized with the original types, not the dynamic
versions, and so any component with a custom serialize may fail. In this
case `Rect` and `Vec2`. The dynamic version includes the field names 'x'
and 'y' but the `Serialize` impl doesn't, hence the "expect float"
error.
The solution here: Instead of using `clone_value` to clone the
components, `FromReflect` clones and retains the original information
needed to serialize with any custom `Serialize` impls. I think using
something like `reflect_clone` from
(https://github.com/bevyengine/bevy/pull/13432) might make this more
efficient.
I also did the same when deserializing dynamic scenes to appease some of
the round-trip tests which use `ReflectPartialEq`, which requires the
types be the same and not a unique/proxy pair. I'm not sure it's
otherwise necessary. Maybe this would also be more efficient when
spawning dynamic scenes with `reflect_clone` instead of `FromReflect`
again?
An alternative solution would be to fall back to the dynamic version
when deserializing `DynamicScene`s if the custom version fails. I think
that's possible. Or maybe simply always deserializing via the dynamic
route for dynamic scenes?
## Testing
This example is similar to the original test case in #10284:
``` rust
#![allow(missing_docs)]
use bevy::{prelude::*, scene::SceneInstanceReady};
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, (save, load).chain())
.observe(check)
.run();
}
static SAVEGAME_SAVE_PATH: &str = "savegame.scn.ron";
fn save(world: &mut World) {
let entity = world.spawn(OrthographicProjection::default()).id();
let scene = DynamicSceneBuilder::from_world(world)
.extract_entity(entity)
.build();
if let Some(registry) = world.get_resource::<AppTypeRegistry>() {
let registry = registry.read();
let serialized_scene = scene.serialize(®istry).unwrap();
// println!("{}", serialized_scene);
std::fs::write(format!("assets/{SAVEGAME_SAVE_PATH}"), serialized_scene).unwrap();
}
world.entity_mut(entity).despawn_recursive();
}
fn load(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(DynamicSceneBundle {
scene: asset_server.load(SAVEGAME_SAVE_PATH),
..default()
});
}
fn check(_trigger: Trigger<SceneInstanceReady>, query: Query<&OrthographicProjection>) {
dbg!(query.single());
}
```
## Migration Guide
The `DynamicScene` format is changed to use custom serialize impls so
old scene files will need updating:
Old:
```ron
(
resources: {},
entities: {
4294967299: (
components: {
"bevy_render:📷:projection::OrthographicProjection": (
near: 0.0,
far: 1000.0,
viewport_origin: (
x: 0.5,
y: 0.5,
),
scaling_mode: WindowSize(1.0),
scale: 1.0,
area: (
min: (
x: -1.0,
y: -1.0,
),
max: (
x: 1.0,
y: 1.0,
),
),
),
},
),
},
)
```
New:
```ron
(
resources: {},
entities: {
4294967299: (
components: {
"bevy_render:📷:projection::OrthographicProjection": (
near: 0.0,
far: 1000.0,
viewport_origin: (0.5, 0.5),
scaling_mode: WindowSize(1.0),
scale: 1.0,
area: (
min: (-1.0, -1.0),
max: (1.0, 1.0),
),
),
},
),
},
)
```
---------
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
# Objective
- `impl_reflect_struct` doesn't cover tuple structs or enums.
- Problem brought up [on
Discord](https://discord.com/channels/691052431525675048/1002362493634629796/1190623345817960463).
## Solution
- Replaces `impl_reflect_struct` with the new `impl_reflect` which works
for tuple structs and enums too.
---
## Changelog
- Internally in `bevy_reflect_derive`, we have a new `ReflectProvenance`
type which is composed of `ReflectTraitToImpl` and `ReflectSource`.
- `impl_reflect_struct` is gone and totally superseded by
`impl_reflect`.
---------
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
Adopted from #8954, co-authored by @pyrotechnick
# Objective
The Bevy ecosystem currently reflects `Quat` via "value" rather than the
more appropriate "struct" strategy. This behaviour is inconsistent to
that of similar types, i.e. `Vec3`. Additionally, employing the "value"
strategy causes instances of `Quat` to be serialised as a sequence `[x,
y, z, w]` rather than structures of shape `{ x, y, z, w }`.
The [comments surrounding the applicable
code](bec299fa6e/crates/bevy_reflect/src/impls/glam.rs (L254))
give context and historical reasons for this discrepancy:
```
// Quat fields are read-only (as of now), and reflection is currently missing
// mechanisms for read-only fields. I doubt those mechanisms would be added,
// so for now quaternions will remain as values. They are represented identically
// to Vec4 and DVec4, so you may use those instead and convert between.
```
This limitation has [since been lifted by the upstream
crate](374625163e),
glam.
## Solution
Migrating the reflect strategy of Quat from "value" to "struct" via
replacing `impl_reflect_value` with `impl_reflect_struct` resolves the
issue.
## Changelog
Migrated `Quat` reflection strategy to "struct" from "value"
Migration Guide
Changed Quat serialization/deserialization from sequences `[x, y, z, w]`
to structures `{ x, y, z, w }`.
---------
Co-authored-by: pyrotechnick <13998+pyrotechnick@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Glam 0.24 added new glam types (```I64Vec``` and ```U64Vec```). However
these are not reflectable unlike the other glam types
## Solution
Implement reflect for these new types
---
## Changelog
Implements reflect with the impl_reflect_struct macro on ```I64Vec2```,
```I64Vec3```, ```I64Vec4```, ```U64Vec2```, ```U64Vec3```, and
```U64Vec4``` types
# Objective
**This implementation is based on
https://github.com/bevyengine/rfcs/pull/59.**
---
Resolves#4597
Full details and motivation can be found in the RFC, but here's a brief
summary.
`FromReflect` is a very powerful and important trait within the
reflection API. It allows Dynamic types (e.g., `DynamicList`, etc.) to
be formed into Real ones (e.g., `Vec<i32>`, etc.).
This mainly comes into play concerning deserialization, where the
reflection deserializers both return a `Box<dyn Reflect>` that almost
always contain one of these Dynamic representations of a Real type. To
convert this to our Real type, we need to use `FromReflect`.
It also sneaks up in other ways. For example, it's a required bound for
`T` in `Vec<T>` so that `Vec<T>` as a whole can be made `FromReflect`.
It's also required by all fields of an enum as it's used as part of the
`Reflect::apply` implementation.
So in other words, much like `GetTypeRegistration` and `Typed`, it is
very much a core reflection trait.
The problem is that it is not currently treated like a core trait and is
not automatically derived alongside `Reflect`. This makes using it a bit
cumbersome and easy to forget.
## Solution
Automatically derive `FromReflect` when deriving `Reflect`.
Users can then choose to opt-out if needed using the
`#[reflect(from_reflect = false)]` attribute.
```rust
#[derive(Reflect)]
struct Foo;
#[derive(Reflect)]
#[reflect(from_reflect = false)]
struct Bar;
fn test<T: FromReflect>(value: T) {}
test(Foo); // <-- OK
test(Bar); // <-- Panic! Bar does not implement trait `FromReflect`
```
#### `ReflectFromReflect`
This PR also automatically adds the `ReflectFromReflect` (introduced in
#6245) registration to the derived `GetTypeRegistration` impl— if the
type hasn't opted out of `FromReflect` of course.
<details>
<summary><h4>Improved Deserialization</h4></summary>
> **Warning**
> This section includes changes that have since been descoped from this
PR. They will likely be implemented again in a followup PR. I am mainly
leaving these details in for archival purposes, as well as for reference
when implementing this logic again.
And since we can do all the above, we might as well improve
deserialization. We can now choose to deserialize into a Dynamic type or
automatically convert it using `FromReflect` under the hood.
`[Un]TypedReflectDeserializer::new` will now perform the conversion and
return the `Box`'d Real type.
`[Un]TypedReflectDeserializer::new_dynamic` will work like what we have
now and simply return the `Box`'d Dynamic type.
```rust
// Returns the Real type
let reflect_deserializer = UntypedReflectDeserializer::new(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
let output: SomeStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?;
// Returns the Dynamic type
let reflect_deserializer = UntypedReflectDeserializer::new_dynamic(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
let output: DynamicStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?;
```
</details>
---
## Changelog
* `FromReflect` is now automatically derived within the `Reflect` derive
macro
* This includes auto-registering `ReflectFromReflect` in the derived
`GetTypeRegistration` impl
* ~~Renamed `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` to
`TypedReflectDeserializer::new_dynamic` and
`UntypedReflectDeserializer::new_dynamic`, respectively~~ **Descoped**
* ~~Changed `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` to automatically convert the
deserialized output using `FromReflect`~~ **Descoped**
## Migration Guide
* `FromReflect` is now automatically derived within the `Reflect` derive
macro. Items with both derives will need to remove the `FromReflect`
one.
```rust
// OLD
#[derive(Reflect, FromReflect)]
struct Foo;
// NEW
#[derive(Reflect)]
struct Foo;
```
If using a manual implementation of `FromReflect` and the `Reflect`
derive, users will need to opt-out of the automatic implementation.
```rust
// OLD
#[derive(Reflect)]
struct Foo;
impl FromReflect for Foo {/* ... */}
// NEW
#[derive(Reflect)]
#[reflect(from_reflect = false)]
struct Foo;
impl FromReflect for Foo {/* ... */}
```
<details>
<summary><h4>Removed Migrations</h4></summary>
> **Warning**
> This section includes changes that have since been descoped from this
PR. They will likely be implemented again in a followup PR. I am mainly
leaving these details in for archival purposes, as well as for reference
when implementing this logic again.
* The reflect deserializers now perform a `FromReflect` conversion
internally. The expected output of `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` is no longer a Dynamic (e.g.,
`DynamicList`), but its Real counterpart (e.g., `Vec<i32>`).
```rust
let reflect_deserializer =
UntypedReflectDeserializer::new_dynamic(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
// OLD
let output: DynamicStruct = reflect_deserializer.deserialize(&mut
deserializer)?.take()?;
// NEW
let output: SomeStruct = reflect_deserializer.deserialize(&mut
deserializer)?.take()?;
```
Alternatively, if this behavior isn't desired, use the
`TypedReflectDeserializer::new_dynamic` and
`UntypedReflectDeserializer::new_dynamic` methods instead:
```rust
// OLD
let reflect_deserializer = UntypedReflectDeserializer::new(®istry);
// NEW
let reflect_deserializer =
UntypedReflectDeserializer::new_dynamic(®istry);
```
</details>
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Introduce a stable alternative to
[`std::any::type_name`](https://doc.rust-lang.org/std/any/fn.type_name.html).
- Rewrite of #5805 with heavy inspiration in design.
- On the path to #5830.
- Part of solving #3327.
## Solution
- Add a `TypePath` trait for static stable type path/name information.
- Add a `TypePath` derive macro.
- Add a `impl_type_path` macro for implementing internal and foreign
types in `bevy_reflect`.
---
## Changelog
- Added `TypePath` trait.
- Added `DynamicTypePath` trait and `get_type_path` method to `Reflect`.
- Added a `TypePath` derive macro.
- Added a `bevy_reflect::impl_type_path` for implementing `TypePath` on
internal and foreign types in `bevy_reflect`.
- Changed `bevy_reflect::utility::(Non)GenericTypeInfoCell` to
`(Non)GenericTypedCell<T>` which allows us to be generic over both
`TypeInfo` and `TypePath`.
- `TypePath` is now a supertrait of `Asset`, `Material` and
`Material2d`.
- `impl_reflect_struct` needs a `#[type_path = "..."]` attribute to be
specified.
- `impl_reflect_value` needs to either specify path starting with a
double colon (`::core::option::Option`) or an `in my_crate::foo`
declaration.
- Added `bevy_reflect_derive::ReflectTypePath`.
- Most uses of `Ident` in `bevy_reflect_derive` changed to use
`ReflectTypePath`.
## Migration Guide
- Implementors of `Asset`, `Material` and `Material2d` now also need to
derive `TypePath`.
- Manual implementors of `Reflect` will need to implement the new
`get_type_path` method.
## Open Questions
- [x] ~This PR currently does not migrate any usages of
`std::any::type_name` to use `bevy_reflect::TypePath` to ease the review
process. Should it?~ Migration will be left to a follow-up PR.
- [ ] This PR adds a lot of `#[derive(TypePath)]` and `T: TypePath` to
satisfy new bounds, mostly when deriving `TypeUuid`. Should we make
`TypePath` a supertrait of `TypeUuid`? [Should we remove `TypeUuid` in
favour of
`TypePath`?](2afbd85532 (r961067892))
# Objective
- Fixes#3004
## Solution
- Replaced all the types with their fully quallified names
- Replaced all trait methods and inherent methods on dyn traits with their fully qualified names
- Made a new file `fq_std.rs` that contains structs corresponding to commonly used Structs and Traits from `std`. These structs are replaced by their respective fully qualified names when used inside `quote!`
# Objective
> Part of #6573
When serializing a `DynamicScene` we end up treating almost all non-value types as though their type data doesn't exist. This is because when creating the `DynamicScene` we call `Reflect::clone_value` on the components, which generates a Dynamic type for all non-value types.
What this means is that the `glam` types are treated as though their `ReflectSerialize` registrations don't exist. However, the deserializer _does_ pick up the registration and attempts to use that instead. This results in the deserializer trying to operate on "malformed" data, causing this error:
```
WARN bevy_asset::asset_server: encountered an error while loading an asset: Expected float
```
## Solution
Ideally, we should better handle the serialization of possibly-Dynamic types. However, this runs into issues where the `ReflectSerialize` expects the concrete type and not a Dynamic representation, resulting in a panic:
0aa4147af6/crates/bevy_reflect/src/type_registry.rs (L402-L413)
Since glam types are so heavily used in Bevy (specifically in `Transform` and `GlobalTransform`), it makes sense to just a quick fix in that enables them to be used properly in scenes while a proper solution is found.
This PR simply removes all `ReflectSerialize` and `ReflectDeserialize` registrations from the glam types that are reflected as structs.
---
## Changelog
- Remove `ReflectSerialize` and `ReflectDeserialize` registrations from most glam types
## Migration Guide
This PR removes `ReflectSerialize` and `ReflectDeserialize` registrations from most glam types. This means any code relying on either of those type data existing for those glam types will need to not do that.
This also means that some serialized glam types will need to be updated. For example, here is `Affine3A`:
```rust
// BEFORE
(
"glam::f32::affine3a::Affine3A": (1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0),
// AFTER
"glam::f32::affine3a::Affine3A": (
matrix3: (
x_axis: (
x: 1.0,
y: 0.0,
z: 0.0,
),
y_axis: (
x: 0.0,
y: 1.0,
z: 0.0,
),
z_axis: (
x: 0.0,
y: 0.0,
z: 1.0,
),
),
translation: (
x: 0.0,
y: 0.0,
z: 0.0,
),
)
)
```
> Note: This is rebased off #4561 and can be viewed as a competitor to that PR. See `Comparison with #4561` section for details.
# Objective
The current serialization format used by `bevy_reflect` is both verbose and error-prone. Taking the following structs[^1] for example:
```rust
// -- src/inventory.rs
#[derive(Reflect)]
struct Inventory {
id: String,
max_storage: usize,
items: Vec<Item>
}
#[derive(Reflect)]
struct Item {
name: String
}
```
Given an inventory of a single item, this would serialize to something like:
```rust
// -- assets/inventory.ron
{
"type": "my_game::inventory::Inventory",
"struct": {
"id": {
"type": "alloc::string::String",
"value": "inv001",
},
"max_storage": {
"type": "usize",
"value": 10
},
"items": {
"type": "alloc::vec::Vec<alloc::string::String>",
"list": [
{
"type": "my_game::inventory::Item",
"struct": {
"name": {
"type": "alloc::string::String",
"value": "Pickaxe"
},
},
},
],
},
},
}
```
Aside from being really long and difficult to read, it also has a few "gotchas" that users need to be aware of if they want to edit the file manually. A major one is the requirement that you use the proper keys for a given type. For structs, you need `"struct"`. For lists, `"list"`. For tuple structs, `"tuple_struct"`. And so on.
It also ***requires*** that the `"type"` entry come before the actual data. Despite being a map— which in programming is almost always orderless by default— the entries need to be in a particular order. Failure to follow the ordering convention results in a failure to deserialize the data.
This makes it very prone to errors and annoyances.
## Solution
Using #4042, we can remove a lot of the boilerplate and metadata needed by this older system. Since we now have static access to type information, we can simplify our serialized data to look like:
```rust
// -- assets/inventory.ron
{
"my_game::inventory::Inventory": (
id: "inv001",
max_storage: 10,
items: [
(
name: "Pickaxe"
),
],
),
}
```
This is much more digestible and a lot less error-prone (no more key requirements and no more extra type names).
Additionally, it is a lot more familiar to users as it follows conventional serde mechanics. For example, the struct is represented with `(...)` when serialized to RON.
#### Custom Serialization
Additionally, this PR adds the opt-in ability to specify a custom serde implementation to be used rather than the one created via reflection. For example[^1]:
```rust
// -- src/inventory.rs
#[derive(Reflect, Serialize)]
#[reflect(Serialize)]
struct Item {
#[serde(alias = "id")]
name: String
}
```
```rust
// -- assets/inventory.ron
{
"my_game::inventory::Inventory": (
id: "inv001",
max_storage: 10,
items: [
(
id: "Pickaxe"
),
],
),
},
```
By allowing users to define their own serialization methods, we do two things:
1. We give more control over how data is serialized/deserialized to the end user
2. We avoid having to re-define serde's attributes and forcing users to apply both (e.g. we don't need a `#[reflect(alias)]` attribute).
### Improved Formats
One of the improvements this PR provides is the ability to represent data in ways that are more conventional and/or familiar to users. Many users are familiar with RON so here are some of the ways we can now represent data in RON:
###### Structs
```js
{
"my_crate::Foo": (
bar: 123
)
}
// OR
{
"my_crate::Foo": Foo(
bar: 123
)
}
```
<details>
<summary>Old Format</summary>
```js
{
"type": "my_crate::Foo",
"struct": {
"bar": {
"type": "usize",
"value": 123
}
}
}
```
</details>
###### Tuples
```js
{
"(f32, f32)": (1.0, 2.0)
}
```
<details>
<summary>Old Format</summary>
```js
{
"type": "(f32, f32)",
"tuple": [
{
"type": "f32",
"value": 1.0
},
{
"type": "f32",
"value": 2.0
}
]
}
```
</details>
###### Tuple Structs
```js
{
"my_crate::Bar": ("Hello World!")
}
// OR
{
"my_crate::Bar": Bar("Hello World!")
}
```
<details>
<summary>Old Format</summary>
```js
{
"type": "my_crate::Bar",
"tuple_struct": [
{
"type": "alloc::string::String",
"value": "Hello World!"
}
]
}
```
</details>
###### Arrays
It may be a bit surprising to some, but arrays now also use the tuple format. This is because they essentially _are_ tuples (a sequence of values with a fixed size), but only allow for homogenous types. Additionally, this is how RON handles them and is probably a result of the 32-capacity limit imposed on them (both by [serde](https://docs.rs/serde/latest/serde/trait.Serialize.html#impl-Serialize-for-%5BT%3B%2032%5D) and by [bevy_reflect](https://docs.rs/bevy/latest/bevy/reflect/trait.GetTypeRegistration.html#impl-GetTypeRegistration-for-%5BT%3B%2032%5D)).
```js
{
"[i32; 3]": (1, 2, 3)
}
```
<details>
<summary>Old Format</summary>
```js
{
"type": "[i32; 3]",
"array": [
{
"type": "i32",
"value": 1
},
{
"type": "i32",
"value": 2
},
{
"type": "i32",
"value": 3
}
]
}
```
</details>
###### Enums
To make things simple, I'll just put a struct variant here, but the style applies to all variant types:
```js
{
"my_crate::ItemType": Consumable(
name: "Healing potion"
)
}
```
<details>
<summary>Old Format</summary>
```js
{
"type": "my_crate::ItemType",
"enum": {
"variant": "Consumable",
"struct": {
"name": {
"type": "alloc::string::String",
"value": "Healing potion"
}
}
}
}
```
</details>
### Comparison with #4561
This PR is a rebased version of #4561. The reason for the split between the two is because this PR creates a _very_ different scene format. You may notice that the PR descriptions for either PR are pretty similar. This was done to better convey the changes depending on which (if any) gets merged first. If #4561 makes it in first, I will update this PR description accordingly.
---
## Changelog
* Re-worked serialization/deserialization for reflected types
* Added `TypedReflectDeserializer` for deserializing data with known `TypeInfo`
* Renamed `ReflectDeserializer` to `UntypedReflectDeserializer`
* ~~Replaced usages of `deserialize_any` with `deserialize_map` for non-self-describing formats~~ Reverted this change since there are still some issues that need to be sorted out (in a separate PR). By reverting this, crates like `bincode` can throw an error when attempting to deserialize non-self-describing formats (`bincode` results in `DeserializeAnyNotSupported`)
* Structs, tuples, tuple structs, arrays, and enums are now all de/serialized using conventional serde methods
## Migration Guide
* This PR reduces the verbosity of the scene format. Scenes will need to be updated accordingly:
```js
// Old format
{
"type": "my_game::item::Item",
"struct": {
"id": {
"type": "alloc::string::String",
"value": "bevycraft:stone",
},
"tags": {
"type": "alloc::vec::Vec<alloc::string::String>",
"list": [
{
"type": "alloc::string::String",
"value": "material"
},
],
},
}
// New format
{
"my_game::item::Item": (
id: "bevycraft:stone",
tags: ["material"]
)
}
```
[^1]: Some derives omitted for brevity.
# Objective
- To implement `Reflect` for more glam types.
## Solution
insert `impl_reflect_struct` invocations for more glam types. I am not sure about the boolean vectors, since none of them implement `Serde::Serialize/Deserialize`, and the SIMD versions don't have public fields.
I do still think implementing reflection is useful for BVec's since then they can be incorporated into `Reflect`'ed components and set dynamically even if as a whole + it's more consistent.
## Changelog
Implemented `Reflect` for the following types
- BVec2
- BVec3
- **BVec3A** (on simd supported platforms only)
- BVec4
- **BVec4A** (on simd supported platforms only)
- Mat2
- Mat3A
- DMat2
- Affine2
- Affine3A
- DAffine2
- DAffine3
- EulerRot
builds on top of #4780
# Objective
`Reflect` and `Serialize` are currently very tied together because `Reflect` has a `fn serialize(&self) -> Option<Serializable<'_>>` method. Because of that, we can either implement `Reflect` for types like `Option<T>` with `T: Serialize` and have `fn serialize` be implemented, or without the bound but having `fn serialize` return `None`.
By separating `ReflectSerialize` into a separate type (like how it already is for `ReflectDeserialize`, `ReflectDefault`), we could separately `.register::<Option<T>>()` and `.register_data::<Option<T>, ReflectSerialize>()` only if the type `T: Serialize`.
This PR does not change the registration but allows it to be changed in a future PR.
## Solution
- add the type
```rust
struct ReflectSerialize { .. }
impl<T: Reflect + Serialize> FromType<T> for ReflectSerialize { .. }
```
- remove `#[reflect(Serialize)]` special casing.
- when serializing reflect value types, look for `ReflectSerialize` in the `TypeRegistry` instead of calling `value.serialize()`
# Objective
Debugging reflected types can be somewhat frustrating since all `dyn Reflect` trait objects return something like `Reflect(core::option::Option<alloc::string::String>)`.
It would be much nicer to be able to see the actual value— or even use a custom `Debug` implementation.
## Solution
Added `Reflect::debug` which allows users to customize the debug output. It sets defaults for all `ReflectRef` subtraits and falls back to `Reflect(type_name)` if no `Debug` implementation was registered.
To register a custom `Debug` impl, users can add `#[reflect(Debug)]` like they can with other traits.
### Example
Using the following structs:
```rust
#[derive(Reflect)]
pub struct Foo {
a: usize,
nested: Bar,
#[reflect(ignore)]
_ignored: NonReflectedValue,
}
#[derive(Reflect)]
pub struct Bar {
value: Vec2,
tuple_value: (i32, String),
list_value: Vec<usize>,
// We can't determine debug formatting for Option<T> yet
unknown_value: Option<String>,
custom_debug: CustomDebug
}
#[derive(Reflect)]
#[reflect(Debug)]
struct CustomDebug;
impl Debug for CustomDebug {
fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
write!(f, "This is a custom debug!")
}
}
pub struct NonReflectedValue {
_a: usize,
}
```
We can do:
```rust
let value = Foo {
a: 1,
_ignored: NonReflectedValue { _a: 10 },
nested: Bar {
value: Vec2::new(1.23, 3.21),
tuple_value: (123, String::from("Hello")),
list_value: vec![1, 2, 3],
unknown_value: Some(String::from("World")),
custom_debug: CustomDebug
},
};
let reflected_value: &dyn Reflect = &value;
println!("{:#?}", reflected_value)
```
Which results in:
```rust
Foo {
a: 2,
nested: Bar {
value: Vec2(
1.23,
3.21,
),
tuple_value: (
123,
"Hello",
),
list_value: [
1,
2,
3,
],
unknown_value: Reflect(core::option::Option<alloc::string::String>),
custom_debug: This is a custom debug!,
},
}
```
Notice that neither `Foo` nor `Bar` implement `Debug`, yet we can still deduce it. This might be a concern if we're worried about leaking internal values. If it is, we might want to consider a way to exclude fields (possibly with a `#[reflect(hide)]` macro) or make it purely opt in (as opposed to the default implementation automatically handled by ReflectRef subtraits).
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
# Objective
Relevant issue: #4474
Currently glam types implement Reflect as a value, which is problematic for reflection, making scripting/editor work much more difficult. This PR re-implements them as structs.
## Solution
Added a new proc macro, `impl_reflect_struct`, which replaces `impl_reflect_value` and `impl_from_reflect_value` for glam types. This macro could also be used for other types, but I don't know of any that would require it. It's specifically useful for foreign types that cannot derive Reflect normally.
---
## Changelog
### Added
- `impl_reflect_struct` proc macro
### Changed
- Glam reflect impls have been replaced with `impl_reflect_struct`
- from_reflect's `impl_struct` altered to take an optional custom constructor, allowing non-default non-constructible foreign types to use it
- Calls to `impl_struct` altered to conform to new signature
- Altered glam types (All vec/mat combinations) have a different serialization structure, as they are reflected differently now.
## Migration Guide
This will break altered glam types serialized to RON scenes, as they will expect to be serialized/deserialized as structs rather than values now. A future PR to add custom serialization for non-value types is likely on the way to restore previous behavior. Additionally, calls to `impl_struct` must add a `None` parameter to the end of the call to restore previous behavior.
Co-authored-by: PROMETHIA-27 <42193387+PROMETHIA-27@users.noreply.github.com>
## Objective
A step towards `f64` `Transform`s (#1680). For now, I am rolling my own `Transform`. But in order to derive Reflect, I specifically need `DQuat` to be reflectable.
```rust
#[derive(Component, Reflect, Copy, Clone, PartialEq, Debug)]
#[reflect(Component, PartialEq)]
pub struct Transform {
pub translation: DVec3,
pub rotation: DQuat, // error: the trait `bevy::prelude::Reflect` is not implemented for `DQuat`
pub scale: DVec3,
}
```
## Solution
I have added a `DQuat` impl for `Reflect` alongside the other glam impls. I've also added impls for `DMat3` and `DMat4` to match.
# Objective
`Vec3A` is does not implement `Reflect`. This is generally useful for `Reflect` derives using `Vec3A` fields, and may speed up some animation blending use cases.
## Solution
Extend the existing macro uses to include `Vec3A`.
Dynamic types (`DynamicStruct`, `DynamicTupleStruct`, `DynamicTuple`, `DynamicList` and `DynamicMap`) are used when deserializing scenes, but currently they can only be applied to existing concrete types. This leads to issues when trying to spawn non trivial deserialized scene.
For components, the issue is avoided by requiring that reflected components implement ~~`FromResources`~~ `FromWorld` (or `Default`). When spawning, a new concrete type is created that way, and the dynamic type is applied to it. Unfortunately, some components don't have any valid implementation of these traits.
In addition, any `Vec` or `HashMap` inside a component will panic when a dynamic type is pushed into it (for instance, `Text` panics when adding a text section).
To solve this issue, this PR adds the `FromReflect` trait that creates a concrete type from a dynamic type that represent it, derives the trait alongside the `Reflect` trait, drops the ~~`FromResources`~~ `FromWorld` requirement on reflected components, ~~and enables reflection for UI and Text bundles~~. It also adds the requirement that fields ignored with `#[reflect(ignore)]` implement `Default`, since we need to initialize them somehow.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
