# Objective
Fixes#3310. Fixes#6282. Fixes#6278. Fixes#3666.
## Solution
Split out `!Send` resources into `NonSendResources`. Add a `origin_thread_id` to all `!Send` Resources, check it on dropping `NonSendResourceData`, if there's a mismatch, panic. Moved all of the checks that `MainThreadValidator` would do into `NonSendResources` instead.
All `!Send` resources now individually track which thread they were inserted from. This is validated against for every access, mutation, and drop that could be done against the value.
A regression test using an altered version of the example from #3310 has been added.
This is a stopgap solution for the current status quo. A full solution may involve fully removing `!Send` resources/components from `World`, which will likely require a much more thorough design on how to handle the existing in-engine and ecosystem use cases.
This PR also introduces another breaking change:
```rust
use bevy_ecs::prelude::*;
#[derive(Resource)]
struct Resource(u32);
fn main() {
let mut world = World::new();
world.insert_resource(Resource(1));
world.insert_non_send_resource(Resource(2));
let res = world.get_resource_mut::<Resource>().unwrap();
assert_eq!(res.0, 2);
}
```
This code will run correctly on 0.9.1 but not with this PR, since NonSend resources and normal resources have become actual distinct concepts storage wise.
## Changelog
Changed: Fix soundness bug with `World: Send`. Dropping a `World` that contains a `!Send` resource on the wrong thread will now panic.
## Migration Guide
Normal resources and `NonSend` resources no longer share the same backing storage. If `R: Resource`, then `NonSend<R>` and `Res<R>` will return different instances from each other. If you are using both `Res<T>` and `NonSend<T>` (or their mutable variants), to fetch the same resources, it's strongly advised to use `Res<T>`.
# Objective
- Fixes#7061
## Solution
- Add and implement `insert` and `remove` methods for `List`.
---
## Changelog
- Added `insert` and `remove` methods to `List`.
- Changed the `push` and `pop` methods on `List` to have default implementations.
## Migration Guide
- Manual implementors of `List` need to implement the new methods `insert` and `remove` and
consider whether to use the new default implementation of `push` and `pop`.
Co-authored-by: radiish <thesethskigamer@gmail.com>
# Objective
Speed up the render phase for rendering.
## Solution
- Follow up #6988 and make the internals of atomic IDs `NonZeroU32`. This niches the `Option`s of the IDs in draw state, which reduces the size and branching behavior when evaluating for equality.
- Require `&RenderDevice` to get the device's `Limits` when initializing a `TrackedRenderPass` to preallocate the bind groups and vertex buffer state in `DrawState`, this removes the branch on needing to resize those `Vec`s.
## Performance
This produces a similar speed up akin to that of #6885. This shows an approximate 6% speed up in `main_opaque_pass_3d` on `many_foxes` (408.79 us -> 388us). This should be orthogonal to the gains seen there.
---
## Changelog
Added: `RenderContext::begin_tracked_render_pass`.
Changed: `TrackedRenderPass` now requires a `&RenderDevice` on construction.
Removed: `bevy_render::render_phase::DrawState`. It was not usable in any form outside of `bevy_render`.
## Migration Guide
TODO
# Objective
- This pulls out some of the changes to Plugin setup and sub apps from #6503 to make that PR easier to review.
- Separate the extract stage from running the sub app's schedule to allow for them to be run on separate threads in the future
- Fixes#6990
## Solution
- add a run method to `SubApp` that runs the schedule
- change the name of `sub_app_runner` to extract to make it clear that this function is only for extracting data between the main app and the sub app
- remove the extract stage from the sub app schedule so it can be run separately. This is done by adding a `setup` method to the `Plugin` trait that runs after all plugin build methods run. This is required to allow the extract stage to be removed from the schedule after all the plugins have added their systems to the stage. We will also need the setup method for pipelined rendering to setup the render thread. See e3267965e1/crates/bevy_render/src/pipelined_rendering.rs (L57-L98)
## Changelog
- Separate SubApp Extract stage from running the sub app schedule.
## Migration Guide
### SubApp `runner` has conceptually been changed to an `extract` function.
The `runner` no longer is in charge of running the sub app schedule. It's only concern is now moving data between the main world and the sub app. The `sub_app.app.schedule` is now run for you after the provided function is called.
```rust
// before
fn main() {
let sub_app = App::empty();
sub_app.add_stage(MyStage, SystemStage::parallel());
App::new().add_sub_app(MySubApp, sub_app, move |main_world, sub_app| {
extract(app_world, render_app);
render_app.app.schedule.run();
});
}
// after
fn main() {
let sub_app = App::empty();
sub_app.add_stage(MyStage, SystemStage::parallel());
App::new().add_sub_app(MySubApp, sub_app, move |main_world, sub_app| {
extract(app_world, render_app);
// schedule is automatically called for you after extract is run
});
}
```
# Objective
- Remove redundant gamepad events
- Simplify consuming gamepad events.
- Refactor: Separate handling of gamepad events into multiple systems.
## Solution
- Removed `GamepadEventRaw`, and `GamepadEventType`.
- Added bespoke `GamepadConnectionEvent`, `GamepadAxisChangedEvent`, and `GamepadButtonChangedEvent`.
- Refactored `gamepad_event_system`.
- Added `gamepad_button_event_system`, `gamepad_axis_event_system`, and `gamepad_connection_system`, which update the `Input` and `Axis` resources using their corresponding event type.
Gamepad events are now handled in their own systems and have their own types.
This allows for querying for gamepad events without having to match on `GamepadEventType` and makes creating handlers for specific gamepad event types, like a `GamepadConnectionEvent` or `GamepadButtonChangedEvent` possible.
We remove `GamepadEventRaw` by filtering the gamepad events, using `GamepadSettings`, _at the source_, in `bevy_gilrs`. This way we can create `GamepadEvent`s directly and avoid creating `GamepadEventRaw` which do not pass the user defined filters.
We expose ordered `GamepadEvent`s and we can respond to individual gamepad event types.
## Migration Guide
- Replace `GamepadEvent` and `GamepadEventRaw` types with their specific gamepad event type.
# Objective
- Fixes https://github.com/bevyengine/bevy/discussions/6338
This PR allows for smooth transitions between different animations.
## Solution
- This PR uses very simple linear blending of animations.
- When starting a new animation, you can give it a duration, and throughout that duration, the previous and the new animation are being linearly blended, until only the new animation is running.
- I'm aware of https://github.com/bevyengine/rfcs/pull/49 and https://github.com/bevyengine/rfcs/pull/51, which are more complete solutions to this problem, but they seem still far from being implemented. Until they're ready, this PR allows for the most basic use case of blending, i.e. smoothly transitioning between different animations.
## Migration Guide
- no bc breaking changes
# Objective
- Storage buffers are useful and not currently supported by the `AsBindGroup` derive which means you need to expand the macro if you need a storage buffer
## Solution
- Add a new `#[storage]` attribute to the derive `AsBindGroup` macro.
- Support and optional `read_only` parameter that defaults to false when not present.
- Support visibility parameters like the texture and sampler attributes.
---
## Changelog
- Add a new `#[storage(index)]` attribute to the derive `AsBindGroup` macro.
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
# Objective
- Avoid slower than necessary first frame after spawning many entities due to them not having `Aabb`s and so being marked visible
- Avoids unnecessarily large system and VRAM allocations as a consequence
## Solution
- I noticed when debugging the `many_cubes` stress test in Xcode that the `MeshUniform` binding was much larger than it needed to be. I realised that this was because initially, all mesh entities are marked as being visible because they don't have `Aabb`s because `calculate_bounds` is being run in `PostUpdate` and there are no system commands applications before executing the visibility check systems that need the `Aabb`s. The solution then is to run the `calculate_bounds` system just before the previous system commands are applied which is at the end of the `Update` stage.
Spiritual successor to #5205.
Actual successor to #6865.
# Objective
Currently, system params are defined using three traits: `SystemParam`, `ReadOnlySystemParam`, `SystemParamState`. The behavior for each param is specified by the `SystemParamState` trait, while `SystemParam` simply defers to the state.
Splitting the traits in this way makes it easier to implement within macros, but it increases the cognitive load. Worst of all, this approach requires each `MySystemParam` to have a public `MySystemParamState` type associated with it.
## Solution
* Merge the trait `SystemParamState` into `SystemParam`.
* Remove all trivial `SystemParam` state types.
* `OptionNonSendMutState<T>`: you will not be missed.
---
- [x] Fix/resolve the remaining test failure.
## Changelog
* Removed the trait `SystemParamState`, merging its functionality into `SystemParam`.
## Migration Guide
**Note**: this should replace the migration guide for #6865.
This is relative to Bevy 0.9, not main.
The traits `SystemParamState` and `SystemParamFetch` have been removed, and their functionality has been transferred to `SystemParam`.
```rust
// Before (0.9)
impl SystemParam for MyParam<'_, '_> {
type State = MyParamState;
}
unsafe impl SystemParamState for MyParamState {
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self { ... }
}
unsafe impl<'w, 's> SystemParamFetch<'w, 's> for MyParamState {
type Item = MyParam<'w, 's>;
fn get_param(&mut self, ...) -> Self::Item;
}
unsafe impl ReadOnlySystemParamFetch for MyParamState { }
// After (0.10)
unsafe impl SystemParam for MyParam<'_, '_> {
type State = MyParamState;
type Item<'w, 's> = MyParam<'w, 's>;
fn init_state(world: &mut World, system_meta: &mut SystemMeta) -> Self::State { ... }
fn get_param<'w, 's>(state: &mut Self::State, ...) -> Self::Item<'w, 's>;
}
unsafe impl ReadOnlySystemParam for MyParam<'_, '_> { }
```
The trait `ReadOnlySystemParamFetch` has been replaced with `ReadOnlySystemParam`.
```rust
// Before
unsafe impl ReadOnlySystemParamFetch for MyParamState {}
// After
unsafe impl ReadOnlySystemParam for MyParam<'_, '_> {}
```
# Objective
- The doctest for `Mut::map_unchanged` uses a fake function `set_if_not_equal` to demonstrate usage.
- Now that #6853 has been merged, we can use `Mut::set_if_neq` directly instead of mocking it.
(github made me type out a message for the commit which looked like it was for the pr, sorry)
# Objective
- Add a way to get all of the input devices of an `Axis`, primarily useful for looping through them
## Solution
- Adds `Axis<T>::devices()` which returns a `FixedSizeIterator<Item = &T>`
- Adds a (probably unneeded) `test_axis_devices` test because tests are cool.
---
## Changelog
- Added `Axis<T>::devices()` method
## Migration Guide
Not a breaking change.
# Objective
`SystemParam` `Local`s documentation currently leaves out information that should be documented.
- What happens when multiple `SystemParam`s within the same system have the same `Local` type.
- What lifetime parameter is expected by `Local`.
## Solution
- Added sentences to documentation to communicate this information.
- Renamed `Local` lifetimes in code to `'s` where they previously were not. Users can get complicated incorrect suggested fixes if they pass the wrong lifetime. Some instance of the code had `'w` indicating the expected lifetime might not have been known to those that wrote the code either.
Co-authored-by: iiYese <83026177+iiYese@users.noreply.github.com>
# 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
- When using `Color::hex` for the first time, I was confused by the fact that I can't specify colors using #, which is much more familiar.
- In the code editor (if there is support) there is a preview of the color, which is very convenient.
## Solution
- Allow you to enter colors like `#ff33f2` and use the `.strip_prefix` method to delete the `#` character.
# Objective
- Fix#4200
Currently, `#[derive(SystemParam)]` publicly exposes each field type, which makes it impossible to encapsulate private fields.
## Solution
Previously, the fields were leaked because they were used as an input generic type to the macro-generated `SystemParam::State` struct. That type has been changed to store its state in a field with a specific type, instead of a generic type.
---
## Changelog
- Fixed a bug that caused `#[derive(SystemParam)]` to leak the types of private fields.
# Objective
- Set the cursor grab mode after the window is built, fix#7007, clean some conversion code.
## Solution
- Set the cursor grab mode after the window is built.
# Objective
Fixes#6891
## Solution
Replaces deserializing map keys as `&str` with deserializing them as `String`.
This bug seems to occur when using something like `File` or `BufReader` rather than bytes or a string directly (I only tested `File` and `BufReader` for `rmp-serde` and `serde_json`). This might be an issue with other `Read` impls as well (except `&[u8]` it seems).
We already had passing tests for Message Pack but none that use a `File` or `BufReader`. This PR also adds or modifies tests to check for this in the future.
This change was also based on [feedback](https://github.com/bevyengine/bevy/pull/4561#discussion_r957385136) I received in a previous PR.
---
## Changelog
- Fix bug where scene deserialization using certain readers could fail (e.g. `BufReader`, `File`, etc.)
# Objective
Speed up animation by leveraging all threads in `ComputeTaskPool`.
## Solution
This PR parallelizes animation sampling across all threads.
To ensure that this is safely done, all animation is predicated with an ancestor query to ensure that there is no conflicting `AnimationPlayer` above each animated hierarchy that may cause this to alias.
Unlike the RFC, this does not add support for reflect based "animate anything", but only extends the existing `AnimationPlayer` to support high numbers of animated characters on screen at once.
## Performance
This cuts `many_foxes`'s frame time on my machine by a full millisecond, from 7.49ms to 6.5ms. (yellow is this PR, red is main).
---
## Changelog
Changed: Animation sampling now runs fully multi-threaded using threads from `ComputeTaskPool`.
Changed: `AnimationPlayer` that are on a child or descendant of another entity with another player will no longer be run.
# Objective
- Fixes#5529
## Solution
- Add assosciated constants named DEFAULT to as many types as possible
- Add const to as many methods in bevy_ui as possible
I have not applied the same treatment to the bundles in bevy_ui as it would require going into other bevy crates to implement const defaults for structs in bevy_text or relies on UiImage which calls HandleUntyped.typed() which isn't const safe.
Alternatively the defaults could relatively easily be turned into a macro to regain some of the readability and conciseness at the cost of explicitness.
Such a macro that partially implements this exists as a crate here: [const-default](https://docs.rs/const-default/latest/const_default/derive.ConstDefault.html) but does not support enums.
Let me know if there's anything I've missed or if I should push further into other crates.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Speed up the render phase of rendering. Simplify the trait structure for render commands.
## Solution
- Merge `EntityPhaseItem` into `PhaseItem` (`EntityPhaseItem::entity` -> `PhaseItem::entity`)
- Merge `EntityRenderCommand` into `RenderCommand`.
- Add two associated types to `RenderCommand`: `RenderCommand::ViewWorldQuery` and `RenderCommand::WorldQuery`.
- Use the new associated types to construct two `QueryStates`s for `RenderCommandState`.
- Hoist any `SQuery<T>` fetches in `EntityRenderCommand`s into the aformentioned two queries. Batch fetch them all at once.
## Performance
`main_opaque_pass_3d` is slightly faster on `many_foxes` (427.52us -> 401.15us)
The shadow pass node is also slightly faster (344.52 -> 338.24us)
## Future Work
- Can we hoist the view level queries out of the core loop?
---
## Changelog
Added: `PhaseItem::entity`
Added: `RenderCommand::ViewWorldQuery` associated type.
Added: `RenderCommand::ItemorldQuery` associated type.
Added: `Draw<T>::prepare` optional trait function.
Removed: `EntityPhaseItem` trait
## Migration Guide
TODO
# Objective
I noticed that running the following command didn't actually do anything:
```
cargo run -p ci -- bench-check
```
## Solution
Made it so that running `cargo run -p ci -- bench-check` actually runs a compile check on the `benches` directory.
# Objective
- The #7064 PR had poor performance on an M1 Max in MacOS due to significant overuse of registers resulting in 'register spilling' where data that would normally be stored in registers on the GPU is instead stored in VRAM. The latency to read from/write to VRAM instead of registers incurs a significant performance penalty.
- Use of registers is a limiting factor in shader performance. Assignment of a struct from memory to a local variable can incur copies. Passing a variable that has struct type as an argument to a function can also incur copies. As such, these two cases can incur increased register usage and decreased performance.
## Solution
- Remove/avoid a number of assignments of light struct type data to local variables.
- Remove/avoid a number of passing light struct type variables/data as value arguments to shader functions.
# Objective
- The recently merged PR #7013 does not allow multiple `RenderPhase`s to share the same `RenderPass`.
- Due to the introduced overhead we want to minimize the number of `RenderPass`es recorded during each frame.
## Solution
- Take a constructed `TrackedRenderPass` instead of a `RenderPassDiscriptor` as a parameter to the `RenderPhase::render` method.
---
## Changelog
To enable multiple `RenderPhases` to share the same `TrackedRenderPass`,
the `RenderPhase::render` signature has changed.
```rust
pub fn render<'w>(
&self,
render_pass: &mut TrackedRenderPass<'w>,
world: &'w World,
view: Entity)
```
Co-authored-by: Kurt Kühnert <51823519+kurtkuehnert@users.noreply.github.com>
# Objective
`Query::get` and other random access methods require looking up `EntityLocation` for every provided entity, then always looking up the `Archetype` to get the table ID and table row. This requires 4 total random fetches from memory: the `Entities` lookup, the `Archetype` lookup, the table row lookup, and the final fetch from table/sparse sets. If `EntityLocation` contains the table ID and table row, only the `Entities` lookup and the final storage fetch are required.
## Solution
Add `TableId` and table row to `EntityLocation`. Ensure it's updated whenever entities are moved around. To ensure `EntityMeta` does not grow bigger, both `TableId` and `ArchetypeId` have been shrunk to u32, and the archetype index and table row are stored as u32s instead of as usizes. This should shrink `EntityMeta` by 4 bytes, from 24 to 20 bytes, as there is no padding anymore due to the change in alignment.
This idea was partially concocted by @BoxyUwU.
## Performance
This should restore the `Query::get` "gains" lost to #6625 that were introduced in #4800 without being unsound, and also incorporates some of the memory usage reductions seen in #3678.
This also removes the same lookups during add/remove/spawn commands, so there may be a bit of a speedup in commands and `Entity{Ref,Mut}`.
---
## Changelog
Added: `EntityLocation::table_id`
Added: `EntityLocation::table_row`.
Changed: `World`s can now only hold a maximum of 2<sup>32</sup>- 1 archetypes.
Changed: `World`s can now only hold a maximum of 2<sup>32</sup> - 1 tables.
## Migration Guide
A `World` can only hold a maximum of 2<sup>32</sup> - 1 archetypes and tables now. If your use case requires more than this, please file an issue explaining your use case.
# Objective
There isn't really a way to test that code using bevy_reflect compiles or doesn't compile for certain scenarios. This would be especially useful for macro-centric PRs like #6511 and #6042.
## Solution
Using `bevy_ecs_compile_fail_tests` as reference, added the `bevy_reflect_compile_fail_tests` crate.
Currently, this crate contains a very simple test case. This is so that we can get the basic foundation of this crate agreed upon and merged so that more tests can be added by other PRs.
### Open Questions
- [x] Should this be added to CI? (Answer: Yes)
---
## Changelog
- Added the `bevy_reflect_compile_fail_tests` crate for testing compilation errors
# Objective
Solve #5464
## Solution
Adds a `SystemInformationDiagnosticsPlugin` to add diagnostics.
Adds `Cargo.toml` flags to fix building on different platforms.
---
## Changelog
Adds `sysinfo` crate to `bevy-diagnostics`.
Changes in import order are due to clippy.
Co-authored-by: l1npengtul <35755164+l1npengtul@users.noreply.github.com>
Co-authored-by: IceSentry <c.giguere42@gmail.com>
# Objective
`xlibsWrapper` is being deprecated: https://github.com/NixOS/nixpkgs/issues/194054, this pr removes the deprecated xlibsWrapper and makes a couple more improvements
## Solution
- rename NixOS to Nix since this is not specific to NixOS
- remove usage of `xlibsWrapper`
- add instructions for nix flakes with `nix develop`
- add example of a packaged bevy program in nixpkgs
- minor cosmetic/grammatical changes
# Objective
I am new to Bevy. And during my development, I noticed that the `iOS` example doesn't work.
Example panics with next message: ```panicked at 'Resource requested by bevy_ui::widget::text::text_system does not exist: bevy_asset::assets::Assets```.
I have asked for help in a `discord` iOS chat and there I receive a recommendation that it is possible that some bevy features missing.
## Solution
So, I used ```bevy``` with default features.
# Objective
`TEXTURE_ADAPTER_SPECIFIC_FORMAT_FEATURES` was already included in `adapter.features()` on non-wasm target, and since it is the default value for `WgpuSettings.features`, the subsequent code will also combine into this feature:
b6066c30b6/crates/bevy_render/src/renderer/mod.rs (L155-L156)
# Objective
Bevy uses custom `Ptr` types so the rust borrow checker can help ensure lifetimes are correct, even when types aren't known. However, these types don't benefit from the automatic lifetime coercion regular rust references enjoy
## Solution
Add a couple methods to Ptr, PtrMut, and MutUntyped to allow for easy usage of these types in more complex scenarios.
## Changelog
- Added `as_mut` and `as_ref` methods to `MutUntyped`.
- Added `shrink` and `as_ref` methods to `PtrMut`.
## Migration Guide
- `MutUntyped::into_inner` now marks things as changed.
# Objective
All `RenderPhases` follow the same render procedure.
The same code is duplicated multiple times across the codebase.
## Solution
I simply extracted this code into a method on the `RenderPhase`.
This avoids code duplication and makes setting up new `RenderPhases` easier.
---
## Changelog
### Changed
You can now set up the rendering code of a `RenderPhase` directly using the `RenderPhase::render` method, instead of implementing it manually in your render graph node.
# Objective
Scene viewer mouse sensitivity/cursor usage isn't the best it could be atm, so just adding some quick, maybe opinionated, tweaks to make it feel more at home in usage.
## Solution
- Mouse delta shouldn't be affected by delta time, it should be more expected that if I move my mouse 1 inch to the right that it should move the in game camera/whatever is controlled the same regardless of FPS.
- Uses a magic number of 180.0 for a nice default sensitivity, modeled after Valorant's default sensitivity.
- Cursor now gets locked/hidden when rotating the camera to give it more of the effect that you are grabbing the camera.
# Objective
- Loading a gltf files prints many errors
```
ERROR bevy_ecs::world: Unable to send event `bevy_hierarchy::events::HierarchyEvent`
Event must be added to the app with `add_event()`
https://docs.rs/bevy/*/bevy/app/struct.App.html#method.add_event
```
- Loading a gltf file create a world for a scene where events are not registered. Executing hierarchy commands on that world should not print error
## Solution
- Revert part of #6921
- don't use `world.send_event` / `world.send_event_batch` from commands
# Objective
- We already log the adapter info on startup when bevy_render is present. It would be nice to have more info about the system to be able to ask users to submit it in bug reports
## Solution
- Use the `sysinfo` crate to get all the information
- I made sure it _only_ gets the required informations to avoid unnecessary system request
- Add a system that logs this on startup
- This system is currently in `bevy_diagnostics` because I didn't really know where to put it.
Here's an example log from my system:
```log
INFO bevy_diagnostic: SystemInformation { os: "Windows 10 Pro", kernel: "19044", cpu: "AMD Ryzen 7 5800X 8-Core Processor", core_count: "8", memory: "34282242 KB" }
```
---
## Changelog
- Added a new default log when starting a bevy app that logs the system information
# Objective
It is often necessary to update an entity's parent while keeping its GlobalTransform static. Currently it is cumbersome and error-prone (two questions in the discord `#help` channel in the past week)
- Part 1 of #5475
- Part 2: #7024.
## Solution
- Add a `reparented_to` method to `GlobalTransform`
---
## Changelog
- Add a `reparented_to` method to `GlobalTransform`
# Objective
Resolve#6156.
The most common type of command is one that runs for a single entity. Built-in commands like this can be ergonomically added to the command queue using the `EntityCommands` struct. However, adding custom entity commands to the queue is quite cumbersome. You must first spawn an entity, store its ID in a local, then construct a command using that ID and add it to the queue. This prevents method chaining, which is the main benefit of using `EntityCommands`.
### Example (before)
```rust
struct MyCustomCommand(Entity);
impl Command for MyCustomCommand { ... }
let id = commands.spawn((...)).id();
commmands.add(MyCustomCommand(id));
```
## Solution
Add the `EntityCommand` trait, which allows directly adding per-entity commands to the `EntityCommands` struct.
### Example (after)
```rust
struct MyCustomCommand;
impl EntityCommand for MyCustomCommand { ... }
commands.spawn((...)).add(MyCustomCommand);
```
---
## Changelog
- Added the trait `EntityCommand`. This is a counterpart of `Command` for types that execute code for a single entity.
## Future Work
If we feel its necessary, we can simplify built-in commands (such as `Despawn`) to use this trait.
# Objective
Any closure with the signature `FnOnce(&mut World)` implicitly implements the trait `Command` due to a blanket implementation. However, this implementation unnecessarily has the `Sync` bound, which limits the types that can be used.
## Solution
Remove the bound.
---
## Changelog
- `Command` closures no longer need to implement the marker trait `std::marker::Sync`.
# Objective
The documentation for camera priority is very confusing at the moment, it requires a bit of "double negative" kind of thinking.
# Solution
Flipping the wording on the documentation to reflect more common usecases like having an overlay camera and also renaming it to "order", since priority implies that it will override the other camera rather than have both run.
