mirror of
https://github.com/bevyengine/bevy
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26 commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Zachary Harrold
|
bf765e61b5
|
Add no_std support to bevy_reflect (#16256)
# 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> |
||
Gino Valente
|
397f20e835
|
bevy_reflect: Generic parameter info (#15475)
# Objective Currently, reflecting a generic type provides no information about the generic parameters. This means that you can't get access to the type of `T` in `Foo<T>` without creating custom type data (we do this for [`ReflectHandle`](https://docs.rs/bevy/0.14.2/bevy/asset/struct.ReflectHandle.html#method.asset_type_id)). ## Solution This PR makes it so that generic type parameters and generic const parameters are tracked in a `Generics` struct stored on the `TypeInfo` for a type. For example, `struct Foo<T, const N: usize>` will store `T` and `N` as a `TypeParamInfo` and `ConstParamInfo`, respectively. The stored information includes: - The name of the generic parameter (i.e. `T`, `N`, etc.) - The type of the generic parameter (remember that we're dealing with monomorphized types, so this will actually be a concrete type) - The default type/value, if any (e.g. `f32` in `T = f32` or `10` in `const N: usize = 10`) ### Caveats The only requirement for this to work is that the user does not opt-out of the automatic `TypePath` derive with `#[reflect(type_path = false)]`. Doing so prevents the macro code from 100% knowing that the generic type implements `TypePath`. This in turn means the generated `Typed` impl can't add generics to the type. There are two solutions for this—both of which I think we should explore in a future PR: 1. We could just not use `TypePath`. This would mean that we can't store the `Type` of the generic, but we can at least store the `TypeId`. 2. We could provide a way to opt out of the automatic `Typed` derive with a `#[reflect(typed = false)]` attribute. This would allow users to manually implement `Typed` to add whatever generic information they need (e.g. skipping a parameter that can't implement `TypePath` while the rest can). I originally thought about making `Generics` an enum with `Generic`, `NonGeneric`, and `Unavailable` variants to signify whether there are generics, no generics, or generics that cannot be added due to opting out of `TypePath`. I ultimately decided against this as I think it adds a bit too much complexity for such an uncommon problem. Additionally, user's don't necessarily _have_ to know the generics of a type, so just skipping them should generally be fine for now. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect ``` --- ## Showcase You can now access generic parameters via `TypeInfo`! ```rust #[derive(Reflect)] struct MyStruct<T, const N: usize>([T; N]); let generics = MyStruct::<f32, 10>::type_info().generics(); // Get by index: let t = generics.get(0).unwrap(); assert_eq!(t.name(), "T"); assert!(t.ty().is::<f32>()); assert!(!t.is_const()); // Or by name: let n = generics.get_named("N").unwrap(); assert_eq!(n.name(), "N"); assert!(n.ty().is::<usize>()); assert!(n.is_const()); ``` You can even access parameter defaults: ```rust #[derive(Reflect)] struct MyStruct<T = String, const N: usize = 10>([T; N]); let generics = MyStruct::<f32, 5>::type_info().generics(); let GenericInfo::Type(info) = generics.get_named("T").unwrap() else { panic!("expected a type parameter"); }; let default = info.default().unwrap(); assert!(default.is::<String>()); let GenericInfo::Const(info) = generics.get_named("N").unwrap() else { panic!("expected a const parameter"); }; let default = info.default().unwrap(); assert_eq!(default.downcast_ref::<usize>().unwrap(), &10); ``` |
||
|
Zachary Harrold
|
d70595b667
|
Add core and alloc over std Lints (#15281)
# Objective - Fixes #6370 - Closes #6581 ## Solution - Added the following lints to the workspace: - `std_instead_of_core` - `std_instead_of_alloc` - `alloc_instead_of_core` - Used `cargo +nightly fmt` with [item level use formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Item%5C%3A) to split all `use` statements into single items. - Used `cargo clippy --workspace --all-targets --all-features --fix --allow-dirty` to _attempt_ to resolve the new linting issues, and intervened where the lint was unable to resolve the issue automatically (usually due to needing an `extern crate alloc;` statement in a crate root). - Manually removed certain uses of `std` where negative feature gating prevented `--all-features` from finding the offending uses. - Used `cargo +nightly fmt` with [crate level use formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Crate%5C%3A) to re-merge all `use` statements matching Bevy's previous styling. - Manually fixed cases where the `fmt` tool could not re-merge `use` statements due to conditional compilation attributes. ## Testing - Ran CI locally ## Migration Guide The MSRV is now 1.81. Please update to this version or higher. ## Notes - This is a _massive_ change to try and push through, which is why I've outlined the semi-automatic steps I used to create this PR, in case this fails and someone else tries again in the future. - Making this change has no impact on user code, but does mean Bevy contributors will be warned to use `core` and `alloc` instead of `std` where possible. - This lint is a critical first step towards investigating `no_std` options for Bevy. --------- Co-authored-by: François Mockers <francois.mockers@vleue.com> |
||
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Gino Valente
|
37443e0f3f
|
bevy_reflect: Add DynamicTyped trait (#15108)
# Objective Thanks to #7207, we now have a way to validate at the type-level that a reflected value is actually the type it says it is and not just a dynamic representation of that type. `dyn PartialReflect` values _might_ be a dynamic type, but `dyn Reflect` values are guaranteed to _not_ be a dynamic type. Therefore, we can start to add methods to `Reflect` that weren't really possible before. For example, we should now be able to always get a `&'static TypeInfo`, and not just an `Option<&'static TypeInfo>`. ## Solution Add the `DynamicTyped` trait. This trait is similar to `DynamicTypePath` in that it provides a way to use the non-object-safe `Typed` trait in an object-safe way. And since all types that derive `Reflect` will also derive `Typed`, we can safely add `DynamicTyped` as a supertrait of `Reflect`. This allows us to use it when just given a `dyn Reflect` trait object. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect ``` --- ## Showcase `Reflect` now has a supertrait of `DynamicTyped`, allowing `TypeInfo` to be retrieved from a `dyn Reflect` trait object without having to unwrap anything! ```rust let value: Box<dyn Reflect> = Box::new(String::from("Hello!")); // BEFORE let info: &'static TypeInfo = value.get_represented_type_info().unwrap(); // AFTER let info: &'static TypeInfo = value.reflect_type_info(); ``` ## Migration Guide `Reflect` now has a supertrait of `DynamicTyped`. If you were manually implementing `Reflect` and did not implement `Typed`, you will now need to do so. |
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Zachary Harrold
|
44620dd6ae
|
Split GenericTypeCell::get_or_insert into smaller pieces (#14865)
# Objective Based on the discussion in #14864, I wanted to experiment with the core `GenericTypeCell` type, whose `get_or_insert` method accounted for 2% of the final binary size of the `3d_scene` example. The reason for this large percentage is likely because the type is fundamental to the rest of Bevy while having 3 generic parameters (the type stored `T`, the type to retrieve `G`, and the function used to insert a new value `F`). - Acts on #14864 ## Solution - Split `get_or_insert` into smaller functions with minimised parameterisation. These new functions are private as to preserve the public facing API, but could be exposed if desired. ## Testing - Ran CI locally. - Used `cargo bloat --release --example 3d_scene -n 100000 --message-format json > out.json` and @cart's [bloat analyzer](https://gist.github.com/cart/722756ba3da0e983d207633e0a48a8ab) to measure a 428KiB reduction in binary size when compiling on Windows 10. - ~I have _not_ benchmarked to determine if this improves/hurts performance.~ See [below](https://github.com/bevyengine/bevy/pull/14865#issuecomment-2306083606). ## Notes In my opinion this seems like a good test-case for the concept of debloating generics within the Bevy codebase. I believe the performance impact here is negligible in either direction (at runtime and compile time), but the binary reduction is measurable and quite significant for a relatively minor change in code. --------- Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com> |
||
radiish
|
6ab8767d3b
|
reflect: implement the unique reflect rfc (#7207)
# Objective
- Implements the [Unique Reflect
RFC](https://github.com/nicopap/rfcs/blob/bevy-reflect-api/rfcs/56-better-reflect.md).
## Solution
- Implements the RFC.
- This implementation differs in some ways from the RFC:
- In the RFC, it was suggested `Reflect: Any` but `PartialReflect:
?Any`. During initial implementation I tried this, but we assume the
`PartialReflect: 'static` in a lot of places and the changes required
crept out of the scope of this PR.
- `PartialReflect::try_into_reflect` originally returned `Option<Box<dyn
Reflect>>` but i changed this to `Result<Box<dyn Reflect>, Box<dyn
PartialReflect>>` since the method takes by value and otherwise there
would be no way to recover the type. `as_full` and `as_full_mut` both
still return `Option<&(mut) dyn Reflect>`.
---
## Changelog
- Added `PartialReflect`.
- `Reflect` is now a subtrait of `PartialReflect`.
- Moved most methods on `Reflect` to the new `PartialReflect`.
- Added `PartialReflect::{as_partial_reflect, as_partial_reflect_mut,
into_partial_reflect}`.
- Added `PartialReflect::{try_as_reflect, try_as_reflect_mut,
try_into_reflect}`.
- Added `<dyn PartialReflect>::{try_downcast_ref, try_downcast_mut,
try_downcast, try_take}` supplementing the methods on `dyn Reflect`.
## Migration Guide
- Most instances of `dyn Reflect` should be changed to `dyn
PartialReflect` which is less restrictive, however trait bounds should
generally stay as `T: Reflect`.
- The new `PartialReflect::{as_partial_reflect, as_partial_reflect_mut,
into_partial_reflect, try_as_reflect, try_as_reflect_mut,
try_into_reflect}` methods as well as `Reflect::{as_reflect,
as_reflect_mut, into_reflect}` will need to be implemented for manual
implementors of `Reflect`.
## Future Work
- This PR is designed to be followed up by another "Unique Reflect Phase
2" that addresses the following points:
- Investigate making serialization revolve around `Reflect` instead of
`PartialReflect`.
- [Remove the `try_*` methods on `dyn PartialReflect` since they are
stop
gaps](https://github.com/bevyengine/bevy/pull/7207#discussion_r1083476050).
- Investigate usages like `ReflectComponent`. In the places they
currently use `PartialReflect`, should they be changed to use `Reflect`?
- Merging this opens the door to lots of reflection features we haven't
been able to implement.
- We could re-add [the `Reflectable`
trait](
|
||
|
Gino Valente
|
aa241672e1
|
bevy_reflect: Nested TypeInfo getters (#13321)
# Objective
Right now, `TypeInfo` can be accessed directly from a type using either
`Typed::type_info` or `Reflect::get_represented_type_info`.
However, once that `TypeInfo` is accessed, any nested types must be
accessed via the `TypeRegistry`.
```rust
#[derive(Reflect)]
struct Foo {
bar: usize
}
let registry = TypeRegistry::default();
let TypeInfo::Struct(type_info) = Foo::type_info() else {
panic!("expected struct info");
};
let field = type_info.field("bar").unwrap();
let field_info = registry.get_type_info(field.type_id()).unwrap();
assert!(field_info.is::<usize>());;
```
## Solution
Enable nested types within a `TypeInfo` to be retrieved directly.
```rust
#[derive(Reflect)]
struct Foo {
bar: usize
}
let TypeInfo::Struct(type_info) = Foo::type_info() else {
panic!("expected struct info");
};
let field = type_info.field("bar").unwrap();
let field_info = field.type_info().unwrap();
assert!(field_info.is::<usize>());;
```
The particular implementation was chosen for two reasons.
Firstly, we can't just store `TypeInfo` inside another `TypeInfo`
directly. This is because some types are recursive and would result in a
deadlock when trying to create the `TypeInfo` (i.e. it has to create the
`TypeInfo` before it can use it, but it also needs the `TypeInfo` before
it can create it). Therefore, we must instead store the function so it
can be retrieved lazily.
I had considered also using a `OnceLock` or something to lazily cache
the info, but I figured we can look into optimizations later. The API
should remain the same with or without the `OnceLock`.
Secondly, a new wrapper trait had to be introduced: `MaybeTyped`. Like
`RegisterForReflection`, this trait is `#[doc(hidden)]` and only exists
so that we can properly handle dynamic type fields without requiring
them to implement `Typed`. We don't want dynamic types to implement
`Typed` due to the fact that it would make the return type
`Option<&'static TypeInfo>` for all types even though only the dynamic
types ever need to return `None` (see #6971 for details).
Users should never have to interact with this trait as it has a blanket
impl for all `Typed` types. And `Typed` is automatically implemented
when deriving `Reflect` (as it is required).
The one downside is we do need to return `Option<&'static TypeInfo>`
from all these new methods so that we can handle the dynamic cases. If
we didn't have to, we'd be able to get rid of the `Option` entirely. But
I think that's an okay tradeoff for this one part of the API, and keeps
the other APIs intact.
## Testing
This PR contains tests to verify everything works as expected. You can
test locally by running:
```
cargo test --package bevy_reflect
```
---
## Changelog
### Public Changes
- Added `ArrayInfo::item_info` method
- Added `NamedField::type_info` method
- Added `UnnamedField::type_info` method
- Added `ListInfo::item_info` method
- Added `MapInfo::key_info` method
- Added `MapInfo::value_info` method
- All active fields now have a `Typed` bound (remember that this is
automatically satisfied for all types that derive `Reflect`)
### Internal Changes
- Added `MaybeTyped` trait
## Migration Guide
All active fields for reflected types (including lists, maps, tuples,
etc.), must implement `Typed`. For the majority of users this won't have
any visible impact.
However, users implementing `Reflect` manually may need to update their
types to implement `Typed` if they weren't already.
Additionally, custom dynamic types will need to implement the new hidden
`MaybeTyped` trait.
|
||
Brezak
|
9c4ac7c297
|
Finish the work on try_apply (#12646)
# Objective Finish the `try_apply` implementation started in #6770 by @feyokorenhof. Supersedes and closes #6770. Closes #6182 ## Solution Add `try_apply` to `Reflect` and implement it in all the places that implement `Reflect`. --- ## Changelog Added `try_apply` to `Reflect`. --------- Co-authored-by: Feyo Korenhof <feyokorenhof@gmail.com> Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com> |
||
BD103
|
aa2ebbb43f
|
Fix some nightly Clippy lints (#12927)
# Objective - I daily drive nightly Rust when developing Bevy, so I notice when new warnings are raised by `cargo check` and Clippy. - `cargo +nightly clippy` raises a few of these new warnings. ## Solution - Fix most warnings from `cargo +nightly clippy` - I skipped the docs-related warnings because some were covered by #12692. - Use `Clone::clone_from` in applicable scenarios, which can sometimes avoid an extra allocation. - Implement `Default` for structs that have a `pub const fn new() -> Self` method. - Fix an occurrence where generic constraints were defined in both `<C: Trait>` and `where C: Trait`. - Removed generic constraints that were implied by the `Bundle` trait. --- ## Changelog - `BatchingStrategy`, `NonGenericTypeCell`, and `GenericTypeCell` now implement `Default`. |
||
Patrick Walton
|
5f1dd3918b
|
Rework animation to be done in two phases. (#11707)
# Objective Bevy's animation system currently does tree traversals based on `Name` that aren't necessary. Not only do they require in unsafe code because tree traversals are awkward with parallelism, but they are also somewhat slow, brittle, and complex, which manifested itself as way too many queries in #11670. # Solution Divide animation into two phases: animation *advancement* and animation *evaluation*, which run after one another. *Advancement* operates on the `AnimationPlayer` and sets the current animation time to match the game time. *Evaluation* operates on all animation bones in the scene in parallel and sets the transforms and/or morph weights based on the time and the clip. To do this, we introduce a new component, `AnimationTarget`, which the asset loader places on every bone. It contains the ID of the entity containing the `AnimationPlayer`, as well as a UUID that identifies which bone in the animation the target corresponds to. In the case of glTF, the UUID is derived from the full path name to the bone. The rule that `AnimationTarget`s are descendants of the entity containing `AnimationPlayer` is now just a convention, not a requirement; this allows us to eliminate the unsafe code. # Migration guide * `AnimationClip` now uses UUIDs instead of hierarchical paths based on the `Name` component to refer to bones. This has several consequences: - A new component, `AnimationTarget`, should be placed on each bone that you wish to animate, in order to specify its UUID and the associated `AnimationPlayer`. The glTF loader automatically creates these components as necessary, so most uses of glTF rigs shouldn't need to change. - Moving a bone around the tree, or renaming it, no longer prevents an `AnimationPlayer` from affecting it. - Dynamically changing the `AnimationPlayer` component will likely require manual updating of the `AnimationTarget` components. * Entities with `AnimationPlayer` components may now possess descendants that also have `AnimationPlayer` components. They may not, however, animate the same bones. * As they aren't specific to `TypeId`s, `bevy_reflect::utility::NoOpTypeIdHash` and `bevy_reflect::utility::NoOpTypeIdHasher` have been renamed to `bevy_reflect::utility::NoOpHash` and `bevy_reflect::utility::NoOpHasher` respectively. |
||
SpecificProtagonist
|
8faaef17e5
|
Hash stability guarantees (#11690)
# Objective We currently over/underpromise hash stability: - `HashMap`/`HashSet` use `BuildHasherDefault<AHasher>` instead of `RandomState`. As a result, the hash is stable within the same run. - [aHash isn't stable between devices (and versions)](https://github.com/tkaitchuck/ahash?tab=readme-ov-file#goals-and-non-goals), yet it's used for `StableHashMap`/`StableHashSet` - the specialized hashmaps are stable Interestingly, `StableHashMap`/`StableHashSet` aren't used by Bevy itself (anymore). ## Solution Add/fix documentation ## Alternatives For `StableHashMap`/`StableHashSet`: - remove them - revive #7107 --- ## Changelog - added iteration stability guarantees for different hashmaps |
||
|
Zachary Harrold
|
bb13d065d3
|
Removed once_cell (#10079)
# Objective - Fixes #8303 ## Solution - Replaced 1 instance of `OnceBox<T>` with `OnceLock<T>` in `NonGenericTypeCell` ## Notes All changes are in the private side of Bevy, and appear to have no observable change in performance or compilation time. This is purely to reduce the quantity of direct dependencies in Bevy. |
||
|
radiish
|
262846e702
|
reflect: TypePath part 2 (#8768)
# Objective
- Followup to #7184.
- ~Deprecate `TypeUuid` and remove its internal references.~ No longer
part of this PR.
- Use `TypePath` for the type registry, and (de)serialisation instead of
`std::any::type_name`.
- Allow accessing type path information behind proxies.
## Solution
- Introduce methods on `TypeInfo` and friends for dynamically querying
type path. These methods supersede the old `type_name` methods.
- Remove `Reflect::type_name` in favor of `DynamicTypePath::type_path`
and `TypeInfo::type_path_table`.
- Switch all uses of `std::any::type_name` in reflection, non-debugging
contexts to use `TypePath`.
---
## Changelog
- Added `TypePathTable` for dynamically accessing methods on `TypePath`
through `TypeInfo` and the type registry.
- Removed `type_name` from all `TypeInfo`-like structs.
- Added `type_path` and `type_path_table` methods to all `TypeInfo`-like
structs.
- Removed `Reflect::type_name` in favor of
`DynamicTypePath::reflect_type_path` and `TypeInfo::type_path`.
- Changed the signature of all `DynamicTypePath` methods to return
strings with a static lifetime.
## Migration Guide
- Rely on `TypePath` instead of `std::any::type_name` for all stability
guarantees and for use in all reflection contexts, this is used through
with one of the following APIs:
- `TypePath::type_path` if you have a concrete type and not a value.
- `DynamicTypePath::reflect_type_path` if you have an `dyn Reflect`
value without a concrete type.
- `TypeInfo::type_path` for use through the registry or if you want to
work with the represented type of a `DynamicFoo`.
- Remove `type_name` from manual `Reflect` implementations.
- Use `type_path` and `type_path_table` in place of `type_name` on
`TypeInfo`-like structs.
- Use `get_with_type_path(_mut)` over `get_with_type_name(_mut)`.
## Note to reviewers
I think if anything we were a little overzealous in merging #7184 and we
should take that extra care here.
In my mind, this is the "point of no return" for `TypePath` and while I
think we all agree on the design, we should carefully consider if the
finer details and current implementations are actually how we want them
moving forward.
For example [this incorrect `TypePath` implementation for
`String`](
|
||
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Zachary Harrold
|
450328d15e
|
Replaced parking_lot with std::sync (#9545)
# Objective - Fixes #4610 ## Solution - Replaced all instances of `parking_lot` locks with equivalents from `std::sync`. Acquiring locks within `std::sync` can fail, so `.expect("Lock Poisoned")` statements were added where required. ## Comments In [this comment](https://github.com/bevyengine/bevy/issues/4610#issuecomment-1592407881), the lack of deadlock detection was mentioned as a potential reason to not make this change. From what I can gather, Bevy doesn't appear to be using this functionality within the engine. Unless it was expected that a Bevy consumer was expected to enable and use this functionality, it appears to be a feature lost without consequence. Unfortunately, `cpal` and `wgpu` both still rely on `parking_lot`, leaving it in the dependency graph even after this change. From my basic experimentation, this change doesn't appear to have any performance impacts, positive or negative. I tested this using `bevymark` with 50,000 entities and observed 20ms of frame-time before and after the change. More extensive testing with larger/real projects should probably be done. |
||
ClayenKitten
|
ffc572728f
|
Fix typos throughout the project (#9090)
# Objective
Fix typos throughout the project.
## Solution
[`typos`](https://github.com/crate-ci/typos) project was used for
scanning, but no automatic corrections were applied. I checked
everything by hand before fixing.
Most of the changes are documentation/comments corrections. Also, there
are few trivial changes to code (variable name, pub(crate) function name
and a few error/panic messages).
## Unsolved
`bevy_reflect_derive` has
[typo](
|
||
radiish
|
e17fc53aa1
|
reflect: avoid deadlock in GenericTypeCell (#8957)
# Objective - There was a deadlock discovered in the implementation of `bevy_reflect::utility::GenericTypeCell`, when called on a recursive type, e.g. `Vec<Vec<VariableCurve>>` ## Solution - Drop the lock before calling the initialisation function, and then pick it up again afterwards. ## Additional Context - [Discussed on Discord](https://discord.com/channels/691052431525675048/1002362493634629796/1122706835284185108) |
||
Carter Anderson
|
8b9d88f4d0
|
Reflect now requires DynamicTypePath. Remove Reflect::get_type_path() (#8764)
Followup to #7184 This makes `Reflect: DynamicTypePath` which allows us to remove `Reflect::get_type_path`, reducing unnecessary codegen and simplifying `Reflect` implementations. |
||
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radiish
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1efc762924
|
reflect: stable type path v2 (#7184)
# 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`?](
|
||
|
Gino Valente
|
75130bd5ec
|
bevy_reflect: Better proxies (#6971)
# Objective > This PR is based on discussion from #6601 The Dynamic types (e.g. `DynamicStruct`, `DynamicList`, etc.) act as both: 1. Dynamic containers which may hold any arbitrary data 2. Proxy types which may represent any other type Currently, the only way we can represent the proxy-ness of a Dynamic is by giving it a name. ```rust // This is just a dynamic container let mut data = DynamicStruct::default(); // This is a "proxy" data.set_name(std::any::type_name::<Foo>()); ``` This type name is the only way we check that the given Dynamic is a proxy of some other type. When we need to "assert the type" of a `dyn Reflect`, we call `Reflect::type_name` on it. However, because we're only using a string to denote the type, we run into a few gotchas and limitations. For example, hashing a Dynamic proxy may work differently than the type it proxies: ```rust #[derive(Reflect, Hash)] #[reflect(Hash)] struct Foo(i32); let concrete = Foo(123); let dynamic = concrete.clone_dynamic(); let concrete_hash = concrete.reflect_hash(); let dynamic_hash = dynamic.reflect_hash(); // The hashes are not equal because `concrete` uses its own `Hash` impl // while `dynamic` uses a reflection-based hashing algorithm assert_ne!(concrete_hash, dynamic_hash); ``` Because the Dynamic proxy only knows about the name of the type, it's unaware of any other information about it. This means it also differs on `Reflect::reflect_partial_eq`, and may include ignored or skipped fields in places the concrete type wouldn't. ## Solution Rather than having Dynamics pass along just the type name of proxied types, we can instead have them pass around the `TypeInfo`. Now all Dynamic types contain an `Option<&'static TypeInfo>` rather than a `String`: ```diff pub struct DynamicTupleStruct { - type_name: String, + represented_type: Option<&'static TypeInfo>, fields: Vec<Box<dyn Reflect>>, } ``` By changing `Reflect::get_type_info` to `Reflect::represented_type_info`, hopefully we make this behavior a little clearer. And to account for `None` values on these dynamic types, `Reflect::represented_type_info` now returns `Option<&'static TypeInfo>`. ```rust let mut data = DynamicTupleStruct::default(); // Not proxying any specific type assert!(dyn_tuple_struct.represented_type_info().is_none()); let type_info = <Foo as Typed>::type_info(); dyn_tuple_struct.set_represented_type(Some(type_info)); // Alternatively: // let dyn_tuple_struct = foo.clone_dynamic(); // Now we're proxying `Foo` assert!(dyn_tuple_struct.represented_type_info().is_some()); ``` This means that we can have full access to all the static type information for the proxied type. Future work would include transitioning more static type information (trait impls, attributes, etc.) over to the `TypeInfo` so it can actually be utilized by Dynamic proxies. ### Alternatives & Rationale > **Note** > These alternatives were written when this PR was first made using a `Proxy` trait. This trait has since been removed. <details> <summary>View</summary> #### Alternative: The `Proxy<T>` Approach I had considered adding something like a `Proxy<T>` type where `T` would be the Dynamic and would contain the proxied type information. This was nice in that it allows us to explicitly determine whether something is a proxy or not at a type level. `Proxy<DynamicStruct>` proxies a struct. Makes sense. The reason I didn't go with this approach is because (1) tuples, (2) complexity, and (3) `PartialReflect`. The `DynamicTuple` struct allows us to represent tuples at runtime. It also allows us to do something you normally can't with tuples: add new fields. Because of this, adding a field immediately invalidates the proxy (e.g. our info for `(i32, i32)` doesn't apply to `(i32, i32, NewField)`). By going with this PR's approach, we can just remove the type info on `DynamicTuple` when that happens. However, with the `Proxy<T>` approach, it becomes difficult to represent this behavior— we'd have to completely control how we access data for `T` for each `T`. Secondly, it introduces some added complexities (aside from the manual impls for each `T`). Does `Proxy<T>` impl `Reflect`? Likely yes, if we want to represent it as `dyn Reflect`. What `TypeInfo` do we give it? How would we forward reflection methods to the inner type (remember, we don't have specialization)? How do we separate this from Dynamic types? And finally, how do all this in a way that's both logical and intuitive for users? Lastly, introducing a `Proxy` trait rather than a `Proxy<T>` struct is actually more inline with the [Unique Reflect RFC](https://github.com/bevyengine/rfcs/pull/56). In a way, the `Proxy` trait is really one part of the `PartialReflect` trait introduced in that RFC (it's technically not in that RFC but it fits well with it), where the `PartialReflect` serves as a way for proxies to work _like_ concrete types without having full access to everything a concrete `Reflect` type can do. This would help bridge the gap between the current state of the crate and the implementation of that RFC. All that said, this is still a viable solution. If the community believes this is the better path forward, then we can do that instead. These were just my reasons for not initially going with it in this PR. #### Alternative: The Type Registry Approach The `Proxy` trait is great and all, but how does it solve the original problem? Well, it doesn't— yet! The goal would be to start moving information from the derive macro and its attributes to the generated `TypeInfo` since these are known statically and shouldn't change. For example, adding `ignored: bool` to `[Un]NamedField` or a list of impls. However, there is another way of storing this information. This is, of course, one of the uses of the `TypeRegistry`. If we're worried about Dynamic proxies not aligning with their concrete counterparts, we could move more type information to the registry and require its usage. For example, we could replace `Reflect::reflect_hash(&self)` with `Reflect::reflect_hash(&self, registry: &TypeRegistry)`. That's not the _worst_ thing in the world, but it is an ergonomics loss. Additionally, other attributes may have their own requirements, further restricting what's possible without the registry. The `Reflect::apply` method will require the registry as well now. Why? Well because the `map_apply` function used for the `Reflect::apply` impls on `Map` types depends on `Map::insert_boxed`, which (at least for `DynamicMap`) requires `Reflect::reflect_hash`. The same would apply when adding support for reflection-based diffing, which will require `Reflect::reflect_partial_eq`. Again, this is a totally viable alternative. I just chose not to go with it for the reasons above. If we want to go with it, then we can close this PR and we can pursue this alternative instead. #### Downsides Just to highlight a quick potential downside (likely needs more investigation): retrieving the `TypeInfo` requires acquiring a lock on the `GenericTypeInfoCell` used by the `Typed` impls for generic types (non-generic types use a `OnceBox which should be faster). I am not sure how much of a performance hit that is and will need to run some benchmarks to compare against. </details> ### Open Questions 1. Should we use `Cow<'static, TypeInfo>` instead? I think that might be easier for modding? Perhaps, in that case, we need to update `Typed::type_info` and friends as well? 2. Are the alternatives better than the approach this PR takes? Are there other alternatives? --- ## Changelog ### Changed - `Reflect::get_type_info` has been renamed to `Reflect::represented_type_info` - This method now returns `Option<&'static TypeInfo>` rather than just `&'static TypeInfo` ### Added - Added `Reflect::is_dynamic` method to indicate when a type is dynamic - Added a `set_represented_type` method on all dynamic types ### Removed - Removed `TypeInfo::Dynamic` (use `Reflect::is_dynamic` instead) - Removed `Typed` impls for all dynamic types ## Migration Guide - The Dynamic types no longer take a string type name. Instead, they require a static reference to `TypeInfo`: ```rust #[derive(Reflect)] struct MyTupleStruct(f32, f32); let mut dyn_tuple_struct = DynamicTupleStruct::default(); dyn_tuple_struct.insert(1.23_f32); dyn_tuple_struct.insert(3.21_f32); // BEFORE: let type_name = std::any::type_name::<MyTupleStruct>(); dyn_tuple_struct.set_name(type_name); // AFTER: let type_info = <MyTupleStruct as Typed>::type_info(); dyn_tuple_struct.set_represented_type(Some(type_info)); ``` - `Reflect::get_type_info` has been renamed to `Reflect::represented_type_info` and now also returns an `Option<&'static TypeInfo>` (instead of just `&'static TypeInfo`): ```rust // BEFORE: let info: &'static TypeInfo = value.get_type_info(); // AFTER: let info: &'static TypeInfo = value.represented_type_info().unwrap(); ``` - `TypeInfo::Dynamic` and `DynamicInfo` has been removed. Use `Reflect::is_dynamic` instead: ```rust // BEFORE: if matches!(value.get_type_info(), TypeInfo::Dynamic) { // ... } // AFTER: if value.is_dynamic() { // ... } ``` --------- Co-authored-by: radiish <cb.setho@gmail.com> |
||
Johan Klokkhammer Helsing
|
18cfb226db |
Use a fixed state hasher in bevy_reflect for deterministic Reflect::reflect_hash() across processes (#7583)
# Objective - bevy_ggrs uses `reflect_hash` in order to produce checksums for its world snapshots. These checksums are sent between clients in order to detect desyncronization. - However, since we currently use `async::AHasher` with the `std` feature, this means that hashes will always be different for different peers, even if the state is identical. - This means bevy_ggrs needs a way to get a deterministic (fixed) hash. ## Solution - ~~Add a feature to use `bevy_utils::FixedState` for the hasher used by bevy_reflect.~~ - Always use `bevy_utils::FixedState` for initializing the bevy_reflect hasher. --- ## Changelog - bevy_reflect now uses a fixed state for its hasher, which means the output of `Reflect::reflect_hash` is now deterministic across processes. |
||
Gino Valente
|
02fbf16c80 |
bevy_reflect: Add Reflect::into_reflect (#6502)
# Objective
Using `Reflect` we can easily switch between a specific reflection trait object, such as a `dyn Struct`, to a `dyn Reflect` object via `Reflect::as_reflect` or `Reflect::as_reflect_mut`.
```rust
fn do_something(value: &dyn Reflect) {/* ... */}
let foo: Box<dyn Struct> = Box::new(Foo::default());
do_something(foo.as_reflect());
```
However, there is no way to convert a _boxed_ reflection trait object to a `Box<dyn Reflect>`.
## Solution
Add a `Reflect::into_reflect` method which allows converting a boxed reflection trait object back into a boxed `Reflect` trait object.
```rust
fn do_something(value: Box<dyn Reflect>) {/* ... */}
let foo: Box<dyn Struct> = Box::new(Foo::default());
do_something(foo.into_reflect());
```
---
## Changelog
- Added `Reflect::into_reflect`
|
||
Hennadii Chernyshchyk
|
feebbc5ea9 |
Add reflect_owned (#6494)
# Objective There is no way to gen an owned value of `Reflect`. ## Solution Add it! This was originally a part of #6421, but @MrGVSV asked me to create a separate for it to implement reflect diffing. --- ## Changelog ### Added - `Reflect::reflect_owned` to get an owned version of `Reflect`. |
||
Jakob Hellermann
|
e71c4d2802 |
fix nightly clippy warnings (#6395)
# Objective
- fix new clippy lints before they get stable and break CI
## Solution
- run `clippy --fix` to auto-fix machine-applicable lints
- silence `clippy::should_implement_trait` for `fn HandleId::default<T: Asset>`
## Changes
- always prefer `format!("{inline}")` over `format!("{}", not_inline)`
- prefer `Box::default` (or `Box::<T>::default` if necessary) over `Box::new(T::default())`
|
||
|
Gino Valente
|
d30d3e752a |
bevy_reflect: Improve serialization format even more (#5723)
> 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. |
||
PROMETHIA-27
|
c27a3cff6d |
Make Reflect safe to implement (#5010)
# Objective Currently, `Reflect` is unsafe to implement because of a contract in which `any` and `any_mut` must return `self`, or `downcast` will cause UB. This PR makes `Reflect` safe, makes `downcast` not use unsafe, and eliminates this contract. ## Solution This PR adds a method to `Reflect`, `any`. It also renames the old `any` to `as_any`. `any` now takes a `Box<Self>` and returns a `Box<dyn Any>`. --- ## Changelog ### Added: - `any()` method - `represents()` method ### Changed: - `Reflect` is now a safe trait - `downcast()` is now safe - The old `any` is now called `as_any`, and `any_mut` is now `as_mut_any` ## Migration Guide - Reflect derives should not have to change anything - Manual reflect impls will need to remove the `unsafe` keyword, add `any()` implementations, and rename the old `any` and `any_mut` to `as_any` and `as_mut_any`. - Calls to `any`/`any_mut` must be changed to `as_any`/`as_mut_any` ## Points of discussion: - Should renaming `any` be avoided and instead name the new method `any_box`? - ~~Could there be a performance regression from avoiding the unsafe? I doubt it, but this change does seem to introduce redundant checks.~~ - ~~Could/should `is` and `type_id()` be implemented differently? For example, moving `is` onto `Reflect` as an `fn(&self, TypeId) -> bool`~~ Co-authored-by: PROMETHIA-27 <42193387+PROMETHIA-27@users.noreply.github.com> |
||
|
Gino Valente
|
e6f34ba47f |
bevy_reflect: Add statically available type info for reflected types (#4042)
# Objective > Resolves #4504 It can be helpful to have access to type information without requiring an instance of that type. Especially for `Reflect`, a lot of the gathered type information is known at compile-time and should not necessarily require an instance. ## Solution Created a dedicated `TypeInfo` enum to store static type information. All types that derive `Reflect` now also implement the newly created `Typed` trait: ```rust pub trait Typed: Reflect { fn type_info() -> &'static TypeInfo; } ``` > Note: This trait was made separate from `Reflect` due to `Sized` restrictions. If you only have access to a `dyn Reflect`, just call `.get_type_info()` on it. This new trait method on `Reflect` should return the same value as if you had called it statically. If all you have is a `TypeId` or type name, you can get the `TypeInfo` directly from the registry using the `TypeRegistry::get_type_info` method (assuming it was registered). ### Usage Below is an example of working with `TypeInfo`. As you can see, we don't have to generate an instance of `MyTupleStruct` in order to get this information. ```rust #[derive(Reflect)] struct MyTupleStruct(usize, i32, MyStruct); let info = MyTupleStruct::type_info(); if let TypeInfo::TupleStruct(info) = info { assert!(info.is::<MyTupleStruct>()); assert_eq!(std::any::type_name::<MyTupleStruct>(), info.type_name()); assert!(info.field_at(1).unwrap().is::<i32>()); } else { panic!("Expected `TypeInfo::TupleStruct`"); } ``` ### Manual Implementations It's not recommended to manually implement `Typed` yourself, but if you must, you can use the `TypeInfoCell` to automatically create and manage the static `TypeInfo`s for you (which is very helpful for blanket/generic impls): ```rust use bevy_reflect::{Reflect, TupleStructInfo, TypeInfo, UnnamedField}; use bevy_reflect::utility::TypeInfoCell; struct Foo<T: Reflect>(T); impl<T: Reflect> Typed for Foo<T> { fn type_info() -> &'static TypeInfo { static CELL: TypeInfoCell = TypeInfoCell::generic(); CELL.get_or_insert::<Self, _>(|| { let fields = [UnnamedField:🆕:<T>()]; let info = TupleStructInfo:🆕:<Self>(&fields); TypeInfo::TupleStruct(info) }) } } ``` ## Benefits One major benefit is that this opens the door to other serialization methods. Since we can get all the type info at compile time, we can know how to properly deserialize something like: ```rust #[derive(Reflect)] struct MyType { foo: usize, bar: Vec<String> } // RON to be deserialized: ( type: "my_crate::MyType", // <- We now know how to deserialize the rest of this object value: { // "foo" is a value type matching "usize" "foo": 123, // "bar" is a list type matching "Vec<String>" with item type "String" "bar": ["a", "b", "c"] } ) ``` Not only is this more compact, but it has better compatibility (we can change the type of `"foo"` to `i32` without having to update our serialized data). Of course, serialization/deserialization strategies like this may need to be discussed and fully considered before possibly making a change. However, we will be better equipped to do that now that we can access type information right from the registry. ## Discussion Some items to discuss: 1. Duplication. There's a bit of overlap with the existing traits/structs since they require an instance of the type while the type info structs do not (for example, `Struct::field_at(&self, index: usize)` and `StructInfo::field_at(&self, index: usize)`, though only `StructInfo` is accessible without an instance object). Is this okay, or do we want to handle it in another way? 2. Should `TypeInfo::Dynamic` be removed? Since the dynamic types don't have type information available at runtime, we could consider them `TypeInfo::Value`s (or just even just `TypeInfo::Struct`). The intention with `TypeInfo::Dynamic` was to keep the distinction from these dynamic types and actual structs/values since users might incorrectly believe the methods of the dynamic type's info struct would map to some contained data (which isn't possible statically). 4. General usefulness of this change, including missing/unnecessary parts. 5. Possible changes to the scene format? (One possible issue with changing it like in the example above might be that we'd have to be careful when handling generic or trait object types.) ## Compile Tests I ran a few tests to compare compile times (as suggested [here](https://github.com/bevyengine/bevy/pull/4042#discussion_r876408143)). I toggled `Reflect` and `FromReflect` derive macros using `cfg_attr` for both this PR ( |