# 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
operate on naga IR directly to improve handling of shader modules.
- give codespan reporting into imported modules
- allow glsl to be used from wgsl and vice-versa
the ultimate objective is to make it possible to
- provide user hooks for core shader functions (to modify light
behaviour within the standard pbr pipeline, for example)
- make automatic binding slot allocation possible
but ... since this is already big, adds some value and (i think) is at
feature parity with the existing code, i wanted to push this now.
## Solution
i made a crate called naga_oil (https://github.com/robtfm/naga_oil -
unpublished for now, could be part of bevy) which manages modules by
- building each module independantly to naga IR
- creating "header" files for each supported language, which are used to
build dependent modules/shaders
- make final shaders by combining the shader IR with the IR for imported
modules
then integrated this into bevy, replacing some of the existing shader
processing stuff. also reworked examples to reflect this.
## Migration Guide
shaders that don't use `#import` directives should work without changes.
the most notable user-facing difference is that imported
functions/variables/etc need to be qualified at point of use, and
there's no "leakage" of visible stuff into your shader scope from the
imports of your imports, so if you used things imported by your imports,
you now need to import them directly and qualify them.
the current strategy of including/'spreading' `mesh_vertex_output`
directly into a struct doesn't work any more, so these need to be
modified as per the examples (e.g. color_material.wgsl, or many others).
mesh data is assumed to be in bindgroup 2 by default, if mesh data is
bound into bindgroup 1 instead then the shader def `MESH_BINDGROUP_1`
needs to be added to the pipeline shader_defs.
# Objective
- Better consistency with `add_systems`.
- Deprecating `add_plugin` in favor of a more powerful `add_plugins`.
- Allow passing `Plugin` to `add_plugins`.
- Allow passing tuples to `add_plugins`.
## Solution
- `App::add_plugins` now takes an `impl Plugins` parameter.
- `App::add_plugin` is deprecated.
- `Plugins` is a new sealed trait that is only implemented for `Plugin`,
`PluginGroup` and tuples over `Plugins`.
- All examples, benchmarks and tests are changed to use `add_plugins`,
using tuples where appropriate.
---
## Changelog
### Changed
- `App::add_plugins` now accepts all types that implement `Plugins`,
which is implemented for:
- Types that implement `Plugin`.
- Types that implement `PluginGroup`.
- Tuples (up to 16 elements) over types that implement `Plugins`.
- Deprecated `App::add_plugin` in favor of `App::add_plugins`.
## Migration Guide
- Replace `app.add_plugin(plugin)` calls with `app.add_plugins(plugin)`.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Use `AppTypeRegistry` on API defined in `bevy_ecs`
(https://github.com/bevyengine/bevy/pull/8895#discussion_r1234748418)
A lot of the API on `Reflect` depends on a registry. When it comes to
the ECS. We should use `AppTypeRegistry` in the general case.
This is however impossible in `bevy_ecs`, since `AppTypeRegistry` is
defined in `bevy_app`.
## Solution
- Move `AppTypeRegistry` resource definition from `bevy_app` to
`bevy_ecs`
- Still add the resource in the `App` plugin, since bevy_ecs itself
doesn't know of plugins
Note that `bevy_ecs` is a dependency of `bevy_app`, so nothing
revolutionary happens.
## Alternative
- Define the API as a trait in `bevy_app` over `bevy_ecs`. (though this
prevents us from using bevy_ecs internals)
- Do not rely on `AppTypeRegistry` for the API in question, requring
users to extract themselves the resource and pass it to the API methods.
---
## Changelog
- Moved `AppTypeRegistry` resource definition from `bevy_app` to
`bevy_ecs`
## Migration Guide
- If you were **not** using a `prelude::*` to import `AppTypeRegistry`,
you should update your imports:
```diff
- use bevy::app::AppTypeRegistry;
+ use bevy::ecs::reflect::AppTypeRegistry
```
# Objective
- Document android code that is currently causing clippy warnings due to
not being documented
## Solution
- Document the two previously undocumented items
# Objective
Discovered that PointLight did not implement FromReflect. Adding
FromReflect where Reflect is used. I overreached and applied this rule
everywhere there was a Reflect without a FromReflect, except from where
the compiler wouldn't allow me.
Based from question: https://github.com/bevyengine/bevy/discussions/8774
## Solution
- Adding FromReflect where Reflect was already derived
## Notes
First PR I do in this ecosystem, so not sure if this is the usual
approach, that is, to touch many files at once.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Updates the requirements on
[notify](https://github.com/notify-rs/notify) to permit the latest
version.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/notify-rs/notify/blob/main/CHANGELOG.md">notify's
changelog</a>.</em></p>
<blockquote>
<h2>notify 6.0.0 (2023-05-17)</h2>
<ul>
<li>CHANGE: files and directories moved into a watch folder on Linux
will now be reported as <code>rename to</code> events instead of
<code>create</code> events <a
href="https://redirect.github.com/notify-rs/notify/issues/480">#480</a></li>
<li>CHANGE: on Linux <code>rename from</code> events will be emitted
immediately without starting a new thread <a
href="https://redirect.github.com/notify-rs/notify/issues/480">#480</a></li>
<li>CHANGE: raise MSRV to 1.60 <a
href="https://redirect.github.com/notify-rs/notify/issues/480">#480</a></li>
</ul>
<h2>debouncer-mini 0.3.0 (2023-05-17)</h2>
<ul>
<li>CHANGE: upgrade to notify 6.0.0, pushing MSRV to 1.60 <a
href="https://redirect.github.com/notify-rs/notify/issues/480">#480</a></li>
</ul>
<h2>debouncer-full 0.1.0 (2023-05-17)</h2>
<p>Newly introduced alternative debouncer with more features. <a
href="https://redirect.github.com/notify-rs/notify/issues/480">#480</a></p>
<ul>
<li>FEATURE: only emit a single <code>rename</code> event if the rename
<code>From</code> and <code>To</code> events can be matched</li>
<li>FEATURE: merge multiple <code>rename</code> events</li>
<li>FEATURE: keep track of the file system IDs all files and stiches
rename events together (FSevents, Windows)</li>
<li>FEATURE: emit only one <code>remove</code> event when deleting a
directory (inotify)</li>
<li>FEATURE: don't emit duplicate create events</li>
<li>FEATURE: don't emit <code>Modify</code> events after a
<code>Create</code> event</li>
</ul>
<p><a
href="https://redirect.github.com/notify-rs/notify/issues/480">#480</a>:
<a
href="https://redirect.github.com/notify-rs/notify/pull/480">notify-rs/notify#480</a></p>
<h2>notify 5.2.0 (2023-05-17)</h2>
<ul>
<li>CHANGE: implement <code>Copy</code> for <code>EventKind</code> and
<code>ModifyKind</code> <a
href="https://redirect.github.com/notify-rs/notify/issues/481">#481</a></li>
</ul>
<p><a
href="https://redirect.github.com/notify-rs/notify/issues/481">#481</a>:
<a
href="https://redirect.github.com/notify-rs/notify/pull/481">notify-rs/notify#481</a></p>
<h2>notify 5.1.0 (2023-01-15)</h2>
<ul>
<li>CHANGE: switch from winapi to windows-sys <a
href="https://redirect.github.com/notify-rs/notify/issues/457">#457</a></li>
<li>FIX: kqueue-backend: batch file-watching together to improve
performance <a
href="https://redirect.github.com/notify-rs/notify/issues/454">#454</a></li>
<li>DOCS: include license file in crate again <a
href="https://redirect.github.com/notify-rs/notify/issues/461">#461</a></li>
<li>DOCS: typo and examples fixups</li>
</ul>
<p><a
href="https://redirect.github.com/notify-rs/notify/issues/454">#454</a>:
<a
href="https://redirect.github.com/notify-rs/notify/pull/454">notify-rs/notify#454</a>
<a
href="https://redirect.github.com/notify-rs/notify/issues/461">#461</a>:
<a
href="https://redirect.github.com/notify-rs/notify/pull/461">notify-rs/notify#461</a>
<a
href="https://redirect.github.com/notify-rs/notify/issues/457">#457</a>:
<a
href="https://redirect.github.com/notify-rs/notify/pull/457">notify-rs/notify#457</a></p>
<h2>debouncer-mini 0.2.1 (2022-09-05)</h2>
<ul>
<li>DOCS: correctly document the <code>crossbeam</code> feature <a
href="https://redirect.github.com/notify-rs/notify/issues/440">#440</a></li>
</ul>
<p><a
href="https://redirect.github.com/notify-rs/notify/issues/440">#440</a>:
<a
href="https://redirect.github.com/notify-rs/notify/pull/440">notify-rs/notify#440</a></p>
<h2>debouncer-mini 0.2.0 (2022-08-30)</h2>
<p>Upgrade notify dependency to 5.0.0</p>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li>See full diff in <a
href="https://github.com/notify-rs/notify/commits">compare view</a></li>
</ul>
</details>
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# Objective
Be consistent with `Resource`s and `Components` and have `Event` types
be more self-documenting.
Although not susceptible to accidentally using a function instead of a
value due to `Event`s only being initialized by their type, much of the
same reasoning for removing the blanket impl on `Resource` also applies
here.
* Not immediately obvious if a type is intended to be an event
* Prevent invisible conflicts if the same third-party or primitive types
are used as events
* Allows for further extensions (e.g. opt-in warning for missed events)
## Solution
Remove the blanket impl for the `Event` trait. Add a derive macro for
it.
---
## Changelog
- `Event` is no longer implemented for all applicable types. Add the
`#[derive(Event)]` macro for events.
## Migration Guide
* Add the `#[derive(Event)]` macro for events. Third-party types used as
events should be wrapped in a newtype.
# Objective
I was trying to add some `Diagnostics` to have a better break down of
performance but I noticed that the current implementation uses a
`ResMut` which forces the functions to all run sequentially whereas
before they could run in parallel. This created too great a performance
penalty to be usable.
## Solution
This PR reworks how the diagnostics work with a couple of breaking
changes. The idea is to change how `Diagnostics` works by changing it to
a `SystemParam`. This allows us to hold a `Deferred` buffer of
measurements that can be applied later, avoiding the need for multiple
mutable references to the hashmap. This means we can run systems that
write diagnostic measurements in parallel.
Firstly, we rename the old `Diagnostics` to `DiagnosticsStore`. This
clears up the original name for the new interface while allowing us to
preserve more closely the original API.
Then we create a new `Diagnostics` struct which implements `SystemParam`
and contains a deferred `SystemBuffer`. This can be used very similar to
the old `Diagnostics` for writing new measurements.
```rust
fn system(diagnostics: ResMut<Diagnostics>) { diagnostics.new_measurement(ID, || 10.0)}
// changes to
fn system(mut diagnostics: Diagnostics) { diagnostics.new_measurement(ID, || 10.0)}
```
For reading the diagnostics, the user needs to change from `Diagnostics`
to `DiagnosticsStore` but otherwise the function calls are the same.
Finally, we add a new method to the `App` for registering diagnostics.
This replaces the old method of creating a startup system and adding it
manually.
Testing it, this PR does indeed allow Diagnostic systems to be run in
parallel.
## Changelog
- Change `Diagnostics` to implement `SystemParam` which allows
diagnostic systems to run in parallel.
## Migration Guide
- Register `Diagnostic`'s using the new
`app.register_diagnostic(Diagnostic::new(DIAGNOSTIC_ID,
"diagnostic_name", 10));`
- In systems for writing new measurements, change `mut diagnostics:
ResMut<Diagnostics>` to `mut diagnostics: Diagnostics` to allow the
systems to run in parallel.
- In systems for reading measurements, change `diagnostics:
Res<Diagnostics>` to `diagnostics: Res<DiagnosticsStore>`.
# 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
- Fix#5631
## Solution
- Wait 50ms (configurable) after the last modification event before
reloading an asset.
---
## Changelog
- `AssetPlugin::watch_for_changes` is now a `ChangeWatcher` instead of a
`bool`
- Fixed https://github.com/bevyengine/bevy/issues/5631
## Migration Guide
- Replace `AssetPlugin::watch_for_changes: true` with e.g.
`ChangeWatcher::with_delay(Duration::from_millis(200))`
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
- Add Reflect and FromReflect for AssetPath
- Fixes#8458
## Solution
- Straightforward derive of `Reflect` and `FromReflect` for `AssetPath`
- Implement `Reflect` and `FromReflect` for `Cow<'static, Path>` as to
satisfy the 'static lifetime requierments of bevy_reflect.
Implementation is a direct copy of that for `Cow<'static, str>` so maybe
it begs the question that was already asked in #7429 - maybe it would be
benefitial to write a general implementation for `Reflect` for
`Cow<'static, T>`.
# Objective
Ensure future consistency between the two compare functions for all
types with manual `Ord` and `PartialOrd` implementations.
## Solution
Use `Self::cpm` in the implementation of `partial_cpm` for types
`Handle` and `Name`.
# Objective
Currently, there isn't a clean way of getting an untyped handle to an
asset during asset loading. This is useful for when an asset needs to
reference other assets, but may not know the concrete type of each
asset.
We could "hack" this together by just using some random asset:
```rust
// We don't care what `bar.baz` is, so we "pretend" it's an `Image`
let handle: Handle<Image> = load_context.get_handle("foo/bar.baz");
```
This should work since we don't actually care about the underlying type
in this case. However, we can do better.
## Solution
Add the `LoadContext::get_handle_untyped` method to get untyped handles
to assets.
Links in the api docs are nice. I noticed that there were several places
where structs / functions and other things were referenced in the docs,
but weren't linked. I added the links where possible / logical.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
# Objective
The clippy lint `type_complexity` is known not to play well with bevy.
It frequently triggers when writing complex queries, and taking the
lint's advice of using a type alias almost always just obfuscates the
code with no benefit. Because of this, this lint is currently ignored in
CI, but unfortunately it still shows up when viewing bevy code in an
IDE.
As someone who's made a fair amount of pull requests to this repo, I
will say that this issue has been a consistent thorn in my side. Since
bevy code is filled with spurious, ignorable warnings, it can be very
difficult to spot the *real* warnings that must be fixed -- most of the
time I just ignore all warnings, only to later find out that one of them
was real after I'm done when CI runs.
## Solution
Suppress this lint in all bevy crates. This was previously attempted in
#7050, but the review process ended up making it more complicated than
it needs to be and landed on a subpar solution.
The discussion in https://github.com/rust-lang/rust-clippy/pull/10571
explores some better long-term solutions to this problem. Since there is
no timeline on when these solutions may land, we should resolve this
issue in the meantime by locally suppressing these lints.
### Unresolved issues
Currently, these lints are not suppressed in our examples, since that
would require suppressing the lint in every single source file. They are
still ignored in CI.
# Objective
Fixes#6780
## Solution
- record the asset path of each watched file
- call `AssetIo::watch_for_changes` in `LoadContext::read_asset_bytes`
---
## Changelog
### Fixed
- fixed hot reloading for `LoadContext::read_asset_bytes`
### Changed
- `AssetIo::watch_path_for_changes` allows watched path and path to reload to differ
## Migration Guide
- for custom `AssetIo`s, differentiate paths to watch and asset paths to reload as a consequence
Co-authored-by: Vincent Junge <specificprotagonist@posteo.org>
# Objective
Closes#7573
- Make `StartupSet` a base set
## Solution
- Add `#[system_set(base)]` to the enum declaration
- Replace `.in_set(StartupSet::...)` with `.in_base_set(StartupSet::...)`
**Note**: I don't really know what I'm doing and what exactly the difference between base and non-base sets are. I mostly opened this PR based on discussion in Discord. I also don't really know how to test that I didn't break everything. Your reviews are appreciated!
---
## Changelog
- `StartupSet` is now a base set
## Migration Guide
`StartupSet` is now a base set. This means that you have to use `.in_base_set` instead of `.in_set`:
### Before
```rs
app.add_system(foo.in_set(StartupSet::PreStartup))
```
### After
```rs
app.add_system(foo.in_base_set(StartupSet::PreStartup))
```
# Objective
We have a few old system labels that are now system sets but are still named or documented as labels. Documentation also generally mentioned system labels in some places.
## Solution
- Clean up naming and documentation regarding system sets
## Migration Guide
`PrepareAssetLabel` is now called `PrepareAssetSet`
# Objective
NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267.
"Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365).
## Solution
This adds "base sets" as a variant of `SystemSet`:
A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive:
```rust
#[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)]
#[system_set(base)]
enum MyBaseSet {
A,
B,
}
```
**Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build.
**Base sets cannot belong to other sets**: this is where the word "base" comes from
Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set.
```rust
app.add_system(foo.in_base_set(MyBaseSet::A))
// X must be a normal set ... base sets cannot be added to base sets
.configure_set(X.in_base_set(MyBaseSet::A))
```
Base sets can still be configured like normal sets:
```rust
app.add_system(MyBaseSet::B.after(MyBaseSet::Ap))
```
The primary use case for base sets is enabling a "default base set":
```rust
schedule.set_default_base_set(CoreSet::Update)
// this will belong to CoreSet::Update by default
.add_system(foo)
// this will override the default base set with PostUpdate
.add_system(bar.in_base_set(CoreSet::PostUpdate))
```
This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides.
---
## Changelog
- Added "base sets" and ported CoreSet to use them.
## Migration Guide
TODO
Huge thanks to @maniwani, @devil-ira, @hymm, @cart, @superdump and @jakobhellermann for the help with this PR.
# Objective
- Followup #6587.
- Minimal integration for the Stageless Scheduling RFC: https://github.com/bevyengine/rfcs/pull/45
## Solution
- [x] Remove old scheduling module
- [x] Migrate new methods to no longer use extension methods
- [x] Fix compiler errors
- [x] Fix benchmarks
- [x] Fix examples
- [x] Fix docs
- [x] Fix tests
## Changelog
### Added
- a large number of methods on `App` to work with schedules ergonomically
- the `CoreSchedule` enum
- `App::add_extract_system` via the `RenderingAppExtension` trait extension method
- the private `prepare_view_uniforms` system now has a public system set for scheduling purposes, called `ViewSet::PrepareUniforms`
### Removed
- stages, and all code that mentions stages
- states have been dramatically simplified, and no longer use a stack
- `RunCriteriaLabel`
- `AsSystemLabel` trait
- `on_hierarchy_reports_enabled` run criteria (now just uses an ad hoc resource checking run condition)
- systems in `RenderSet/Stage::Extract` no longer warn when they do not read data from the main world
- `RunCriteriaLabel`
- `transform_propagate_system_set`: this was a nonstandard pattern that didn't actually provide enough control. The systems are already `pub`: the docs have been updated to ensure that the third-party usage is clear.
### Changed
- `System::default_labels` is now `System::default_system_sets`.
- `App::add_default_labels` is now `App::add_default_sets`
- `CoreStage` and `StartupStage` enums are now `CoreSet` and `StartupSet`
- `App::add_system_set` was renamed to `App::add_systems`
- The `StartupSchedule` label is now defined as part of the `CoreSchedules` enum
- `.label(SystemLabel)` is now referred to as `.in_set(SystemSet)`
- `SystemLabel` trait was replaced by `SystemSet`
- `SystemTypeIdLabel<T>` was replaced by `SystemSetType<T>`
- The `ReportHierarchyIssue` resource now has a public constructor (`new`), and implements `PartialEq`
- Fixed time steps now use a schedule (`CoreSchedule::FixedTimeStep`) rather than a run criteria.
- Adding rendering extraction systems now panics rather than silently failing if no subapp with the `RenderApp` label is found.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied.
- `SceneSpawnerSystem` now runs under `CoreSet::Update`, rather than `CoreStage::PreUpdate.at_end()`.
- `bevy_pbr::add_clusters` is no longer an exclusive system
- the top level `bevy_ecs::schedule` module was replaced with `bevy_ecs::scheduling`
- `tick_global_task_pools_on_main_thread` is no longer run as an exclusive system. Instead, it has been replaced by `tick_global_task_pools`, which uses a `NonSend` resource to force running on the main thread.
## Migration Guide
- Calls to `.label(MyLabel)` should be replaced with `.in_set(MySet)`
- Stages have been removed. Replace these with system sets, and then add command flushes using the `apply_system_buffers` exclusive system where needed.
- The `CoreStage`, `StartupStage, `RenderStage` and `AssetStage` enums have been replaced with `CoreSet`, `StartupSet, `RenderSet` and `AssetSet`. The same scheduling guarantees have been preserved.
- Systems are no longer added to `CoreSet::Update` by default. Add systems manually if this behavior is needed, although you should consider adding your game logic systems to `CoreSchedule::FixedTimestep` instead for more reliable framerate-independent behavior.
- Similarly, startup systems are no longer part of `StartupSet::Startup` by default. In most cases, this won't matter to you.
- For example, `add_system_to_stage(CoreStage::PostUpdate, my_system)` should be replaced with
- `add_system(my_system.in_set(CoreSet::PostUpdate)`
- When testing systems or otherwise running them in a headless fashion, simply construct and run a schedule using `Schedule::new()` and `World::run_schedule` rather than constructing stages
- Run criteria have been renamed to run conditions. These can now be combined with each other and with states.
- Looping run criteria and state stacks have been removed. Use an exclusive system that runs a schedule if you need this level of control over system control flow.
- For app-level control flow over which schedules get run when (such as for rollback networking), create your own schedule and insert it under the `CoreSchedule::Outer` label.
- Fixed timesteps are now evaluated in a schedule, rather than controlled via run criteria. The `run_fixed_timestep` system runs this schedule between `CoreSet::First` and `CoreSet::PreUpdate` by default.
- Command flush points introduced by `AssetStage` have been removed. If you were relying on these, add them back manually.
- Adding extract systems is now typically done directly on the main app. Make sure the `RenderingAppExtension` trait is in scope, then call `app.add_extract_system(my_system)`.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. You may need to order your movement systems to occur before this system in order to avoid system order ambiguities in culling behavior.
- the `RenderLabel` `AppLabel` was renamed to `RenderApp` for clarity
- `App::add_state` now takes 0 arguments: the starting state is set based on the `Default` impl.
- Instead of creating `SystemSet` containers for systems that run in stages, simply use `.on_enter::<State::Variant>()` or its `on_exit` or `on_update` siblings.
- `SystemLabel` derives should be replaced with `SystemSet`. You will also need to add the `Debug`, `PartialEq`, `Eq`, and `Hash` traits to satisfy the new trait bounds.
- `with_run_criteria` has been renamed to `run_if`. Run criteria have been renamed to run conditions for clarity, and should now simply return a bool.
- States have been dramatically simplified: there is no longer a "state stack". To queue a transition to the next state, call `NextState::set`
## TODO
- [x] remove dead methods on App and World
- [x] add `App::add_system_to_schedule` and `App::add_systems_to_schedule`
- [x] avoid adding the default system set at inappropriate times
- [x] remove any accidental cycles in the default plugins schedule
- [x] migrate benchmarks
- [x] expose explicit labels for the built-in command flush points
- [x] migrate engine code
- [x] remove all mentions of stages from the docs
- [x] verify docs for States
- [x] fix uses of exclusive systems that use .end / .at_start / .before_commands
- [x] migrate RenderStage and AssetStage
- [x] migrate examples
- [x] ensure that transform propagation is exported in a sufficiently public way (the systems are already pub)
- [x] ensure that on_enter schedules are run at least once before the main app
- [x] re-enable opt-in to execution order ambiguities
- [x] revert change to `update_bounds` to ensure it runs in `PostUpdate`
- [x] test all examples
- [x] unbreak directional lights
- [x] unbreak shadows (see 3d_scene, 3d_shape, lighting, transparaency_3d examples)
- [x] game menu example shows loading screen and menu simultaneously
- [x] display settings menu is a blank screen
- [x] `without_winit` example panics
- [x] ensure all tests pass
- [x] SubApp doc test fails
- [x] runs_spawn_local tasks fails
- [x] [Fix panic_when_hierachy_cycle test hanging](https://github.com/alice-i-cecile/bevy/pull/120)
## Points of Difficulty and Controversy
**Reviewers, please give feedback on these and look closely**
1. Default sets, from the RFC, have been removed. These added a tremendous amount of implicit complexity and result in hard to debug scheduling errors. They're going to be tackled in the form of "base sets" by @cart in a followup.
2. The outer schedule controls which schedule is run when `App::update` is called.
3. I implemented `Label for `Box<dyn Label>` for our label types. This enables us to store schedule labels in concrete form, and then later run them. I ran into the same set of problems when working with one-shot systems. We've previously investigated this pattern in depth, and it does not appear to lead to extra indirection with nested boxes.
4. `SubApp::update` simply runs the default schedule once. This sucks, but this whole API is incomplete and this was the minimal changeset.
5. `time_system` and `tick_global_task_pools_on_main_thread` no longer use exclusive systems to attempt to force scheduling order
6. Implemetnation strategy for fixed timesteps
7. `AssetStage` was migrated to `AssetSet` without reintroducing command flush points. These did not appear to be used, and it's nice to remove these bottlenecks.
8. Migration of `bevy_render/lib.rs` and pipelined rendering. The logic here is unusually tricky, as we have complex scheduling requirements.
## Future Work (ideally before 0.10)
- Rename schedule_v3 module to schedule or scheduling
- Add a derive macro to states, and likely a `EnumIter` trait of some form
- Figure out what exactly to do with the "systems added should basically work by default" problem
- Improve ergonomics for working with fixed timesteps and states
- Polish FixedTime API to match Time
- Rebase and merge #7415
- Resolve all internal ambiguities (blocked on better tools, especially #7442)
- Add "base sets" to replace the removed default sets.
# Objective
- Update winit to 0.28
## Solution
- Small API change
- A security advisory has been added for a unmaintained crate used by a dependency of winit build script for wayland
I didn't do anything for Android support in this PR though it should be fixable, it should be done in a separate one, maybe https://github.com/bevyengine/bevy/pull/6830
---
## Changelog
- `window.always_on_top` has been removed, you can now use `window.window_level`
## Migration Guide
before:
```rust
app.new()
.add_plugins(DefaultPlugins.set(WindowPlugin {
primary_window: Some(Window {
always_on_top: true,
..default()
}),
..default()
}));
```
after:
```rust
app.new()
.add_plugins(DefaultPlugins.set(WindowPlugin {
primary_window: Some(Window {
window_level: bevy:🪟:WindowLevel::AlwaysOnTop,
..default()
}),
..default()
}));
```
# Objective
- Resolve a Fixme to remove the `Default` impl for `HandleType`, once Reflection no longer requires it.
- Presumebly this Comment was made before the `FromReflect` Derive used the `#[reflect(Default)]`, to substitute for the requirment that a ignored field has a `Default`.
## Solution
- Just remove the `Default` derive and comment.
alternative to #5922, implements #5956
builds on top of https://github.com/bevyengine/bevy/pull/6402
# Objective
https://github.com/bevyengine/bevy/issues/5956 goes into more detail, but the TLDR is:
- bevy systems ensure disjoint accesses to resources and components, and for that to work there are methods `World::get_resource_unchecked_mut(&self)`, ..., `EntityRef::get_mut_unchecked(&self)` etc.
- we don't have these unchecked methods for `by_id` variants, so third-party crate authors cannot build their own safe disjoint-access abstractions with these
- having `_unchecked_mut` methods is not great, because in their presence safe code can accidentally violate subtle invariants. Having to go through `world.as_unsafe_world_cell().unsafe_method()` forces you to stop and think about what you want to write in your `// SAFETY` comment.
The alternative is to keep exposing `_unchecked_mut` variants for every operation that we want third-party crates to build upon, but we'd prefer to avoid using these methods alltogether: https://github.com/bevyengine/bevy/pull/5922#issuecomment-1241954543
Also, this is something that **cannot be implemented outside of bevy**, so having either this PR or #5922 as an escape hatch with lots of discouraging comments would be great.
## Solution
- add `UnsafeWorldCell` with `unsafe fn get_resource(&self)`, `unsafe fn get_resource_mut(&self)`
- add `fn World::as_unsafe_world_cell(&mut self) -> UnsafeWorldCell<'_>` (and `as_unsafe_world_cell_readonly(&self)`)
- add `UnsafeWorldCellEntityRef` with `unsafe fn get`, `unsafe fn get_mut` and the other utilities on `EntityRef` (no methods for spawning, despawning, insertion)
- use the `UnsafeWorldCell` abstraction in `ReflectComponent`, `ReflectResource` and `ReflectAsset`, so these APIs are easier to reason about
- remove `World::get_resource_mut_unchecked`, `EntityRef::get_mut_unchecked` and use `unsafe { world.as_unsafe_world_cell().get_mut() }` and `unsafe { world.as_unsafe_world_cell().get_entity(entity)?.get_mut() }` instead
This PR does **not** make use of `UnsafeWorldCell` for anywhere else in `bevy_ecs` such as `SystemParam` or `Query`. That is a much larger change, and I am convinced that having `UnsafeWorldCell` is already useful for third-party crates.
Implemented API:
```rust
struct World { .. }
impl World {
fn as_unsafe_world_cell(&self) -> UnsafeWorldCell<'_>;
}
struct UnsafeWorldCell<'w>(&'w World);
impl<'w> UnsafeWorldCell {
unsafe fn world(&self) -> &World;
fn get_entity(&self) -> UnsafeWorldCellEntityRef<'w>; // returns 'w which is `'self` of the `World::as_unsafe_world_cell(&'w self)`
unsafe fn get_resource<T>(&self) -> Option<&'w T>;
unsafe fn get_resource_by_id(&self, ComponentId) -> Option<&'w T>;
unsafe fn get_resource_mut<T>(&self) -> Option<Mut<'w, T>>;
unsafe fn get_resource_mut_by_id(&self) -> Option<MutUntyped<'w>>;
unsafe fn get_non_send_resource<T>(&self) -> Option<&'w T>;
unsafe fn get_non_send_resource_mut<T>(&self) -> Option<Mut<'w, T>>>;
// not included: remove, remove_resource, despawn, anything that might change archetypes
}
struct UnsafeWorldCellEntityRef<'w> { .. }
impl UnsafeWorldCellEntityRef<'w> {
unsafe fn get<T>(&self, Entity) -> Option<&'w T>;
unsafe fn get_by_id(&self, Entity, ComponentId) -> Option<Ptr<'w>>;
unsafe fn get_mut<T>(&self, Entity) -> Option<Mut<'w, T>>;
unsafe fn get_mut_by_id(&self, Entity, ComponentId) -> Option<MutUntyped<'w>>;
unsafe fn get_change_ticks<T>(&self, Entity) -> Option<Mut<'w, T>>;
// fn id, archetype, contains, contains_id, containts_type_id
}
```
<details>
<summary>UnsafeWorldCell docs</summary>
Variant of the [`World`] where resource and component accesses takes a `&World`, and the responsibility to avoid
aliasing violations are given to the caller instead of being checked at compile-time by rust's unique XOR shared rule.
### Rationale
In rust, having a `&mut World` means that there are absolutely no other references to the safe world alive at the same time,
without exceptions. Not even unsafe code can change this.
But there are situations where careful shared mutable access through a type is possible and safe. For this, rust provides the [`UnsafeCell`](std::cell::UnsafeCell)
escape hatch, which allows you to get a `*mut T` from a `&UnsafeCell<T>` and around which safe abstractions can be built.
Access to resources and components can be done uniquely using [`World::resource_mut`] and [`World::entity_mut`], and shared using [`World::resource`] and [`World::entity`].
These methods use lifetimes to check at compile time that no aliasing rules are being broken.
This alone is not enough to implement bevy systems where multiple systems can access *disjoint* parts of the world concurrently. For this, bevy stores all values of
resources and components (and [`ComponentTicks`](crate::component::ComponentTicks)) in [`UnsafeCell`](std::cell::UnsafeCell)s, and carefully validates disjoint access patterns using
APIs like [`System::component_access`](crate::system::System::component_access).
A system then can be executed using [`System::run_unsafe`](crate::system::System::run_unsafe) with a `&World` and use methods with interior mutability to access resource values.
access resource values.
### Example Usage
[`UnsafeWorldCell`] can be used as a building block for writing APIs that safely allow disjoint access into the world.
In the following example, the world is split into a resource access half and a component access half, where each one can
safely hand out mutable references.
```rust
use bevy_ecs::world::World;
use bevy_ecs::change_detection::Mut;
use bevy_ecs::system::Resource;
use bevy_ecs::world::unsafe_world_cell_world::UnsafeWorldCell;
// INVARIANT: existance of this struct means that users of it are the only ones being able to access resources in the world
struct OnlyResourceAccessWorld<'w>(UnsafeWorldCell<'w>);
// INVARIANT: existance of this struct means that users of it are the only ones being able to access components in the world
struct OnlyComponentAccessWorld<'w>(UnsafeWorldCell<'w>);
impl<'w> OnlyResourceAccessWorld<'w> {
fn get_resource_mut<T: Resource>(&mut self) -> Option<Mut<'w, T>> {
// SAFETY: resource access is allowed through this UnsafeWorldCell
unsafe { self.0.get_resource_mut::<T>() }
}
}
// impl<'w> OnlyComponentAccessWorld<'w> {
// ...
// }
// the two interior mutable worlds borrow from the `&mut World`, so it cannot be accessed while they are live
fn split_world_access(world: &mut World) -> (OnlyResourceAccessWorld<'_>, OnlyComponentAccessWorld<'_>) {
let resource_access = OnlyResourceAccessWorld(unsafe { world.as_unsafe_world_cell() });
let component_access = OnlyComponentAccessWorld(unsafe { world.as_unsafe_world_cell() });
(resource_access, component_access)
}
```
</details>
# Objective
- Enabling the `debug_asset_server` feature doesn't compile when using it with `load_internal_binary_asset!()`. The issue is because it assumes the loader takes an `&'static str` as a parameter, but binary assets loader expect `&'static [u8]`.
## Solution
- Add a generic type for the loader and use a different type in `load_internal_asset` and `load_internal_binary_asset`
# Objective
- Fixes#7081.
## Solution
- Moved functionality from kitchen sink plugin `CorePlugin` to separate plugins, `TaskPoolPlugin`, `TypeRegistrationPlugin`, `FrameCountPlugin`. `TaskPoolOptions` resource should now be used with `TaskPoolPlugin`.
## Changelog
Minimal changes made (code kept in `bevy_core/lib.rs`).
## Migration Guide
- `CorePlugin` broken into separate plugins. If not using `DefaultPlugins` or `MinimalPlugins` `PluginGroup`s, the replacement for `CorePlugin` is now to add `TaskPoolPlugin`, `TypeRegistrationPlugin`, and `FrameCountPlugin` to the app.
## Notes
- Consistent with Bevy goal "modularity over deep integration" but the functionality of `TypeRegistrationPlugin` and `FrameCountPlugin` is weak (the code has to go somewhere, though!).
- No additional tests written.
# Objective
It is currently possible to break reference counting for assets by creating a strong `HandleUntyped` and then modifying the `id` field before dropping the handle. This should not be allowed.
## Solution
Change the `id` field visibility to private and add a getter instead. The same change was previously done for `Handle<T>` in #6176, but `HandleUntyped` was forgotten.
---
## Migration Guide
- Instead of directly accessing the ID of a `HandleUntyped` as `handle.id`, use the new getter `handle.id()`.
# Objective
- Derive Clone and Debug for `AssetPlugin`
- Make it possible to log asset server settings
- And get an owned instance if wrapping `AssetPlugin` in another plugin. See: 129224ef72/src/web_asset_plugin.rs (L45)
# Objective
The `load_internal_asset` macro is helpful when creating rendering plugins, but it doesn't support load binary assets (like those compiled as spir-v).
## Solution
Add a `load_internal_binary_asset` macro that use `include_bytes!`.
This reverts commit 53d387f340.
# Objective
Reverts #6448. This didn't have the intended effect: we're now getting bevy::prelude shown in the docs again.
Co-authored-by: Alejandro Pascual <alejandro.pascual.pozo@gmail.com>
# Objective
- Right now re-exports are completely hidden in prelude docs.
- Fixes#6433
## Solution
- We could show the re-exports without inlining their documentation.
# Objective
Following discussion on #3536 and #3522, `Handle::as_weak()` takes a type `U`, reinterpreting the handle as of another asset type while keeping the same ID. This is mainly used today in font atlas code. This PR does two things:
- Rename the method to `cast_weak()` to make its intent more clear
- Actually change the type uuid in the handle if it's not an asset path variant.
## Migration Guide
- Rename `Handle::as_weak` uses to `Handle::cast_weak`
The method now properly sets the associated type uuid if the handle is a direct reference (e.g. not a reference to an `AssetPath`), so adjust you code accordingly if you relied on the previous behavior.
# 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())`
# Objective
^ enable this
Concretely, I need to
- list all handle ids for an asset type
- fetch the asset as `dyn Reflect`, given a `HandleUntyped`
- when encountering a `Handle<T>`, find out what asset type that handle refers to (`T`'s type id) and turn the handle into a `HandleUntyped`
## Solution
- add `ReflectAsset` type containing function pointers for working with assets
```rust
pub struct ReflectAsset {
type_uuid: Uuid,
assets_resource_type_id: TypeId, // TypeId of the `Assets<T>` resource
get: fn(&World, HandleUntyped) -> Option<&dyn Reflect>,
get_mut: fn(&mut World, HandleUntyped) -> Option<&mut dyn Reflect>,
get_unchecked_mut: unsafe fn(&World, HandleUntyped) -> Option<&mut dyn Reflect>,
add: fn(&mut World, &dyn Reflect) -> HandleUntyped,
set: fn(&mut World, HandleUntyped, &dyn Reflect) -> HandleUntyped,
len: fn(&World) -> usize,
ids: for<'w> fn(&'w World) -> Box<dyn Iterator<Item = HandleId> + 'w>,
remove: fn(&mut World, HandleUntyped) -> Option<Box<dyn Reflect>>,
}
```
- add `ReflectHandle` type relating the handle back to the asset type and providing a way to create a `HandleUntyped`
```rust
pub struct ReflectHandle {
type_uuid: Uuid,
asset_type_id: TypeId,
downcast_handle_untyped: fn(&dyn Any) -> Option<HandleUntyped>,
}
```
- add the corresponding `FromType` impls
- add a function `app.register_asset_reflect` which is supposed to be called after `.add_asset` and registers `ReflectAsset` and `ReflectHandle` in the type registry
---
## Changelog
- add `ReflectAsset` and `ReflectHandle` types, which allow code to use reflection to manipulate arbitrary assets without knowing their types at compile time
