# Objective
Fixes#7632.
As discussed in #7634, it can be quite challenging for users to intuit the mental model of how states now work.
## Solution
Rather than change the behavior of the `OnUpdate` system set, instead work on making sure it's easy to understand what's going on.
Two things have been done:
1. Remove the `.on_update` method from our bevy of system building traits. This was special-cased and made states feel much more magical than they need to.
2. Improve the docs for the `OnUpdate` system set.
# Objective
Fixes#7565
`ecs_guide` example is currently panicking. This seems to just be a problem with the example only caused by the base sets PR.
## Solution
First, changed a few `in_set` to `in_base_set` to fix a few of
```
thread 'main' panicked at 'Systems cannot be added to 'base' system sets using 'in_set'. Use 'in_base_set' instead.', examples/ecs/ecs_guide.rs:301:45
```
And then added an `in_base_set` to fix the resulting (confusing) cycle error
```
2023-02-06T13:54:29.213843Z ERROR bevy_ecs::schedule_v3::schedule: schedule contains at least 1 cycle(s) -- cycle(s) found within:
---- 0: ["ecs_guide::game_over_system", "ecs_guide::score_check_system"]
```
I also changed this `add_system` call so the comment above and below make sense:
```diff
// add_system(system) adds systems to the Update system set by default
// However we can manually specify the set if we want to. The following is equivalent to
// add_system(score_system)
- .add_system(score_system)
+ .add_system(score_system.in_base_set(CoreSet::Update))
// There are other `CoreSets`, such as `Last` which runs at the very end of each run.
```
## Notes
- Does `MySet` even need to be a base set? Seems like yes.
- Is that cycle error when there is no explicit `in_base_set` actually expected?
# Objective
Implementing `States` manually is repetitive, so let's not.
One thing I'm unsure of is whether the macro import statement is in the right place.
# 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
Removal events are unwieldy and require some knowledge of when to put systems that need to catch events for them, it is very easy to end up missing one and end up with memory leak-ish issues where you don't clean up after yourself.
## Solution
Consolidate removals with the benefits of `Events<...>` (such as double buffering and per system ticks for reading the events) and reduce the special casing of it, ideally I was hoping to move the removals to a `Resource` in the world, but that seems a bit more rough to implement/maintain because of double mutable borrowing issues.
This doesn't go the full length of change detection esque removal detection a la https://github.com/bevyengine/rfcs/pull/44.
Just tries to make the current workflow a bit more user friendly so detecting removals isn't such a scheduling nightmare.
---
## Changelog
- RemovedComponents<T> is now backed by an `Events<Entity>` for the benefits of double buffering.
## Migration Guide
- Add a `mut` for `removed: RemovedComponents<T>` since we are now modifying an event reader internally.
- Iterating over removed components now requires `&mut removed_components` or `removed_components.iter()` instead of `&removed_components`.
# Objective
- Bevy should not have any "internal" execution order ambiguities. These clutter the output of user-facing error reporting, and can result in nasty, nondetermistic, very difficult to solve bugs.
- Verifying this currently involves repeated non-trivial manual work.
## Solution
- [x] add an example to quickly check this
- ~~[ ] ensure that this example panics if there are any unresolved ambiguities~~
- ~~[ ] run the example in CI 😈~~
There's one tricky ambiguity left, between UI and animation. I don't have the tools to fix this without system set configuration, so the remaining work is going to be left to #7267 or another PR after that.
```
2023-01-27T18:38:42.989405Z INFO bevy_ecs::schedule::ambiguity_detection: Execution order ambiguities detected, you might want to add an explicit dependency relation between some of these systems:
* Parallel systems:
-- "bevy_animation::animation_player" and "bevy_ui::flex::flex_node_system"
conflicts: ["bevy_transform::components::transform::Transform"]
```
## Changelog
Resolved internal execution order ambiguities for:
1. Transform propagation (ignored, we need smarter filter checking).
2. Gamepad processing (fixed).
3. bevy_winit's window handling (fixed).
4. Cascaded shadow maps and perspectives (fixed).
Also fixed a desynchronized state bug that could occur when the `Window` component is removed and then added to the same entity in a single frame.
# Objective
I found several words in code and docs are incorrect. This should be fixed.
## Solution
- Fix several minor typos
Co-authored-by: Chris Ohk <utilforever@gmail.com>
# Objective
Fixes#3184. Fixes#6640. Fixes#4798. Using `Query::par_for_each(_mut)` currently requires a `batch_size` parameter, which affects how it chunks up large archetypes and tables into smaller chunks to run in parallel. Tuning this value is difficult, as the performance characteristics entirely depends on the state of the `World` it's being run on. Typically, users will just use a flat constant and just tune it by hand until it performs well in some benchmarks. However, this is both error prone and risks overfitting the tuning on that benchmark.
This PR proposes a naive automatic batch-size computation based on the current state of the `World`.
## Background
`Query::par_for_each(_mut)` schedules a new Task for every archetype or table that it matches. Archetypes/tables larger than the batch size are chunked into smaller tasks. Assuming every entity matched by the query has an identical workload, this makes the worst case scenario involve using a batch size equal to the size of the largest matched archetype or table. Conversely, a batch size of `max {archetype, table} size / thread count * COUNT_PER_THREAD` is likely the sweetspot where the overhead of scheduling tasks is minimized, at least not without grouping small archetypes/tables together.
There is also likely a strict minimum batch size below which the overhead of scheduling these tasks is heavier than running the entire thing single-threaded.
## Solution
- [x] Remove the `batch_size` from `Query(State)::par_for_each` and friends.
- [x] Add a check to compute `batch_size = max {archeytpe/table} size / thread count * COUNT_PER_THREAD`
- [x] ~~Panic if thread count is 0.~~ Defer to `for_each` if the thread count is 1 or less.
- [x] Early return if there is no matched table/archetype.
- [x] Add override option for users have queries that strongly violate the initial assumption that all iterated entities have an equal workload.
---
## Changelog
Changed: `Query::par_for_each(_mut)` has been changed to `Query::par_iter(_mut)` and will now automatically try to produce a batch size for callers based on the current `World` state.
## Migration Guide
The `batch_size` parameter for `Query(State)::par_for_each(_mut)` has been removed. These calls will automatically compute a batch size for you. Remove these parameters from all calls to these functions.
Before:
```rust
fn parallel_system(query: Query<&MyComponent>) {
query.par_for_each(32, |comp| {
...
});
}
```
After:
```rust
fn parallel_system(query: Query<&MyComponent>) {
query.par_iter().for_each(|comp| {
...
});
}
```
Co-authored-by: Arnav Choubey <56453634+x-52@users.noreply.github.com>
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Corey Farwell <coreyf@rwell.org>
Co-authored-by: Aevyrie <aevyrie@gmail.com>
# Objective
Fix https://github.com/bevyengine/bevy/issues/4530
- Make it easier to open/close/modify windows by setting them up as `Entity`s with a `Window` component.
- Make multiple windows very simple to set up. (just add a `Window` component to an entity and it should open)
## Solution
- Move all properties of window descriptor to ~components~ a component.
- Replace `WindowId` with `Entity`.
- ~Use change detection for components to update backend rather than events/commands. (The `CursorMoved`/`WindowResized`/... events are kept for user convenience.~
Check each field individually to see what we need to update, events are still kept for user convenience.
---
## Changelog
- `WindowDescriptor` renamed to `Window`.
- Width/height consolidated into a `WindowResolution` component.
- Requesting maximization/minimization is done on the [`Window::state`] field.
- `WindowId` is now `Entity`.
## Migration Guide
- Replace `WindowDescriptor` with `Window`.
- Change `width` and `height` fields in a `WindowResolution`, either by doing
```rust
WindowResolution::new(width, height) // Explicitly
// or using From<_> for tuples for convenience
(1920., 1080.).into()
```
- Replace any `WindowCommand` code to just modify the `Window`'s fields directly and creating/closing windows is now by spawning/despawning an entity with a `Window` component like so:
```rust
let window = commands.spawn(Window { ... }).id(); // open window
commands.entity(window).despawn(); // close window
```
## Unresolved
- ~How do we tell when a window is minimized by a user?~
~Currently using the `Resize(0, 0)` as an indicator of minimization.~
No longer attempting to tell given how finnicky this was across platforms, now the user can only request that a window be maximized/minimized.
## Future work
- Move `exit_on_close` functionality out from windowing and into app(?)
- https://github.com/bevyengine/bevy/issues/5621
- https://github.com/bevyengine/bevy/issues/7099
- https://github.com/bevyengine/bevy/issues/7098
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Change detection can be spuriously triggered by setting a field to the same value as before. As a result, a common pattern is to write:
```rust
if *foo != value {
*foo = value;
}
```
This is confusing to read, and heavy on boilerplate.
Adopted from #5373, but untangled and rebased to current `bevy/main`.
## Solution
1. Add a method to the `DetectChanges` trait that implements this boilerplate when the appropriate trait bounds are met.
2. Document this minor footgun, and point users to it.
## Changelog
* added the `set_if_neq` method to avoid triggering change detection when the new and previous values are equal. This will work on both components and resources.
## Migration Guide
If you are manually checking if a component or resource's value is equal to its new value before setting it to avoid triggering change detection, migrate to the clearer and more convenient `set_if_neq` method.
## Context
Related to #2363 as it avoids triggering change detection, but not a complete solution (as it still requires triggering it when real changes are made).
Co-authored-by: Zoey <Dessix@Dessix.net>
# Objective
Fixes#6224, add ``dbg``, ``info``, ``warn`` and ``error`` system piping adapter variants to expand #5776, which call the corresponding re-exported [bevy_log macros](https://docs.rs/bevy/latest/bevy/log/macro.info.html) when the result is an error.
## Solution
* Added ``dbg``, ``info``, ``warn`` and ``error`` system piping adapter variants to ``system_piping.rs``.
* Modified and added tests for these under examples in ``system_piping.rs``.
# Objective
Fixes#6498.
## Solution
Adding a parent node with properties AlignItems::Center and JustifyContent::Center to centered child nodes and removing their auto-margin properties.
# 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
- Build on #6336 for more plugin configurations
## Solution
- `LogSettings`, `ImageSettings` and `DefaultTaskPoolOptions` are now plugins settings rather than resources
---
## Changelog
- `LogSettings` plugin settings have been move to `LogPlugin`, `ImageSettings` to `ImagePlugin` and `DefaultTaskPoolOptions` to `CorePlugin`
## Migration Guide
The `LogSettings` settings have been moved from a resource to `LogPlugin` configuration:
```rust
// Old (Bevy 0.8)
app
.insert_resource(LogSettings {
level: Level::DEBUG,
filter: "wgpu=error,bevy_render=info,bevy_ecs=trace".to_string(),
})
.add_plugins(DefaultPlugins)
// New (Bevy 0.9)
app.add_plugins(DefaultPlugins.set(LogPlugin {
level: Level::DEBUG,
filter: "wgpu=error,bevy_render=info,bevy_ecs=trace".to_string(),
}))
```
The `ImageSettings` settings have been moved from a resource to `ImagePlugin` configuration:
```rust
// Old (Bevy 0.8)
app
.insert_resource(ImageSettings::default_nearest())
.add_plugins(DefaultPlugins)
// New (Bevy 0.9)
app.add_plugins(DefaultPlugins.set(ImagePlugin::default_nearest()))
```
The `DefaultTaskPoolOptions` settings have been moved from a resource to `CorePlugin::task_pool_options`:
```rust
// Old (Bevy 0.8)
app
.insert_resource(DefaultTaskPoolOptions::with_num_threads(4))
.add_plugins(DefaultPlugins)
// New (Bevy 0.9)
app.add_plugins(DefaultPlugins.set(CorePlugin {
task_pool_options: TaskPoolOptions::with_num_threads(4),
}))
```
# Objective
- Make `Time` API more consistent.
- Support time accel/decel/pause.
## Solution
This is just the `Time` half of #3002. I was told that part isn't controversial.
- Give the "delta time" and "total elapsed time" methods `f32`, `f64`, and `Duration` variants with consistent naming.
- Implement accelerating / decelerating the passage of time.
- Implement stopping time.
---
## Changelog
- Changed `time_since_startup` to `elapsed` because `time.time_*` is just silly.
- Added `relative_speed` and `set_relative_speed` methods.
- Added `is_paused`, `pause`, `unpause` , and methods. (I'd prefer `resume`, but `unpause` matches `Timer` API.)
- Added `raw_*` variants of the "delta time" and "total elapsed time" methods.
- Added `first_update` method because there's a non-zero duration between startup and the first update.
## Migration Guide
- `time.time_since_startup()` -> `time.elapsed()`
- `time.seconds_since_startup()` -> `time.elapsed_seconds_f64()`
- `time.seconds_since_startup_wrapped_f32()` -> `time.elapsed_seconds_wrapped()`
If you aren't sure which to use, most systems should continue to use "scaled" time (e.g. `time.delta_seconds()`). The realtime "unscaled" time measurements (e.g. `time.raw_delta_seconds()`) are mostly for debugging and profiling.
As mentioned in #2926, it's better to have an explicit type that clearly communicates the intent of the timer mode rather than an opaque boolean, which can be only understood when knowing the signature or having to look up the documentation.
This also opens up a way to merge different timers, such as `Stopwatch`, and possibly future ones, such as `DiscreteStopwatch` and `DiscreteTimer` from #2683, into one struct.
Signed-off-by: Lena Milizé <me@lvmn.org>
# Objective
Fixes#2926.
## Solution
Introduce `TimerMode` which replaces the `bool` argument of `Timer` constructors. A `Default` value for `TimerMode` is `Once`.
---
## Changelog
### Added
- `TimerMode` enum, along with variants `TimerMode::Once` and `TimerMode::Repeating`
### Changed
- Replace `bool` argument of `Timer::new` and `Timer::from_seconds` with `TimerMode`
- Change `repeating: bool` field of `Timer` with `mode: TimerMode`
## Migration Guide
- Replace `Timer::new(duration, false)` with `Timer::new(duration, TimerMode::Once)`.
- Replace `Timer::new(duration, true)` with `Timer::new(duration, TimerMode::Repeating)`.
- Replace `Timer::from_seconds(seconds, false)` with `Timer::from_seconds(seconds, TimerMode::Once)`.
- Replace `Timer::from_seconds(seconds, true)` with `Timer::from_seconds(seconds, TimerMode::Repeating)`.
- Change `timer.repeating()` to `timer.mode() == TimerMode::Repeating`.
# Objective
> System chaining is a confusing name: it implies the ability to construct non-linear graphs, and suggests a sense of system ordering that is only incidentally true. Instead, it actually works by passing data from one system to the next, much like the pipe operator.
> In the accepted [stageless RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/45-stageless.md), this concept is renamed to piping, and "system chaining" is used to construct groups of systems with ordering dependencies between them.
Fixes#6225.
## Changelog
System chaining has been renamed to system piping to improve clarity (and free up the name for new ordering APIs).
## Migration Guide
The `.chain(handler_system)` method on systems is now `.pipe(handler_system)`.
The `IntoChainSystem` trait is now `IntoPipeSystem`, and the `ChainSystem` struct is now `PipeSystem`.
# Objective
The [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) involves allowing exclusive systems to be referenced and ordered relative to parallel systems. We've agreed that unifying systems under `System` is the right move.
This is an alternative to #4166 (see rationale in the comments I left there). Note that this builds on the learnings established there (and borrows some patterns).
## Solution
This unifies parallel and exclusive systems under the shared `System` trait, removing the old `ExclusiveSystem` trait / impls. This is accomplished by adding a new `ExclusiveFunctionSystem` impl similar to `FunctionSystem`. It is backed by `ExclusiveSystemParam`, which is similar to `SystemParam`. There is a new flattened out SystemContainer api (which cuts out a lot of trait and type complexity).
This means you can remove all cases of `exclusive_system()`:
```rust
// before
commands.add_system(some_system.exclusive_system());
// after
commands.add_system(some_system);
```
I've also implemented `ExclusiveSystemParam` for `&mut QueryState` and `&mut SystemState`, which makes this possible in exclusive systems:
```rust
fn some_exclusive_system(
world: &mut World,
transforms: &mut QueryState<&Transform>,
state: &mut SystemState<(Res<Time>, Query<&Player>)>,
) {
for transform in transforms.iter(world) {
println!("{transform:?}");
}
let (time, players) = state.get(world);
for player in players.iter() {
println!("{player:?}");
}
}
```
Note that "exclusive function systems" assume `&mut World` is present (and the first param). I think this is a fair assumption, given that the presence of `&mut World` is what defines the need for an exclusive system.
I added some targeted SystemParam `static` constraints, which removed the need for this:
``` rust
fn some_exclusive_system(state: &mut SystemState<(Res<'static, Time>, Query<&'static Player>)>) {}
```
## Related
- #2923
- #3001
- #3946
## Changelog
- `ExclusiveSystem` trait (and implementations) has been removed in favor of sharing the `System` trait.
- `ExclusiveFunctionSystem` and `ExclusiveSystemParam` were added, enabling flexible exclusive function systems
- `&mut SystemState` and `&mut QueryState` now implement `ExclusiveSystemParam`
- Exclusive and parallel System configuration is now done via a unified `SystemDescriptor`, `IntoSystemDescriptor`, and `SystemContainer` api.
## Migration Guide
Calling `.exclusive_system()` is no longer required (or supported) for converting exclusive system functions to exclusive systems:
```rust
// Old (0.8)
app.add_system(some_exclusive_system.exclusive_system());
// New (0.9)
app.add_system(some_exclusive_system);
```
Converting "normal" parallel systems to exclusive systems is done by calling the exclusive ordering apis:
```rust
// Old (0.8)
app.add_system(some_system.exclusive_system().at_end());
// New (0.9)
app.add_system(some_system.at_end());
```
Query state in exclusive systems can now be cached via ExclusiveSystemParams, which should be preferred for clarity and performance reasons:
```rust
// Old (0.8)
fn some_system(world: &mut World) {
let mut transforms = world.query::<&Transform>();
for transform in transforms.iter(world) {
}
}
// New (0.9)
fn some_system(world: &mut World, transforms: &mut QueryState<&Transform>) {
for transform in transforms.iter(world) {
}
}
```
# Objective
Fixes#6078. The `UiColor` component is unhelpfully named: it is unclear, ambiguous with border color and
## Solution
Rename the `UiColor` component (and associated fields) to `BackgroundColor` / `background_colorl`.
## Migration Guide
`UiColor` has been renamed to `BackgroundColor`. This change affects `NodeBundle`, `ButtonBundle` and `ImageBundle`. In addition, the corresponding field on `ExtractedUiNode` has been renamed to `background_color` for consistency.
# Objective
Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands).
## Solution
All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input:
```rust
// before:
commands
.spawn()
.insert((A, B, C));
world
.spawn()
.insert((A, B, C);
// after
commands.spawn((A, B, C));
world.spawn((A, B, C));
```
All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api.
By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`).
This improves spawn performance by over 10%:
To take this measurement, I added a new `world_spawn` benchmark.
Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main.
**Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).**
---
## Changelog
- All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input
- All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api
- World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior.
## Migration Guide
```rust
// Old (0.8):
commands
.spawn()
.insert_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));
// Old (0.8):
commands.spawn_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));
// Old (0.8):
let entity = commands.spawn().id();
// New (0.9)
let entity = commands.spawn_empty().id();
// Old (0.8)
let entity = world.spawn().id();
// New (0.9)
let entity = world.spawn_empty();
```
# Objective
Take advantage of the "impl Bundle for Component" changes in #2975 / add the follow up changes discussed there.
## Solution
- Change `insert` and `remove` to accept a Bundle instead of a Component (for both Commands and World)
- Deprecate `insert_bundle`, `remove_bundle`, and `remove_bundle_intersection`
- Add `remove_intersection`
---
## Changelog
- Change `insert` and `remove` now accept a Bundle instead of a Component (for both Commands and World)
- `insert_bundle` and `remove_bundle` are deprecated
## Migration Guide
Replace `insert_bundle` with `insert`:
```rust
// Old (0.8)
commands.spawn().insert_bundle(SomeBundle::default());
// New (0.9)
commands.spawn().insert(SomeBundle::default());
```
Replace `remove_bundle` with `remove`:
```rust
// Old (0.8)
commands.entity(some_entity).remove_bundle::<SomeBundle>();
// New (0.9)
commands.entity(some_entity).remove::<SomeBundle>();
```
Replace `remove_bundle_intersection` with `remove_intersection`:
```rust
// Old (0.8)
world.entity_mut(some_entity).remove_bundle_intersection::<SomeBundle>();
// New (0.9)
world.entity_mut(some_entity).remove_intersection::<SomeBundle>();
```
Consider consolidating as many operations as possible to improve ergonomics and cut down on archetype moves:
```rust
// Old (0.8)
commands.spawn()
.insert_bundle(SomeBundle::default())
.insert(SomeComponent);
// New (0.9) - Option 1
commands.spawn().insert((
SomeBundle::default(),
SomeComponent,
))
// New (0.9) - Option 2
commands.spawn_bundle((
SomeBundle::default(),
SomeComponent,
))
```
## Next Steps
Consider changing `spawn` to accept a bundle and deprecate `spawn_bundle`.
@BoxyUwU this is your fault.
Also cart didn't arrive in time to tell us not to do this.
# Objective
- Fix#2974
## Solution
- The first commit just does the actual change
- Follow up commits do steps to prove that this method works to unify as required, but this does not remove `insert_bundle`.
## Changelog
### Changed
Nested bundles now collapse automatically, and every `Component` now implements `Bundle`.
This means that you can combine bundles and components arbitrarily, for example:
```rust
// before:
.insert(A).insert_bundle(MyBBundle{..})
// after:
.insert_bundle((A, MyBBundle {..}))
```
Note that there will be a follow up PR that removes the current `insert` impl and renames `insert_bundle` to `insert`.
### Removed
The `bundle` attribute in `derive(Bundle)`.
## Migration guide
In `derive(Bundle)`, the `bundle` attribute has been removed. Nested bundles are not collapsed automatically. You should remove `#[bundle]` attributes.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Since `identity` is a const fn that takes no arguments it seems logical to make it an associated constant.
This is also more in line with types from glam (eg. `Quat::IDENTITY`).
## Migration Guide
The method `identity()` on `Transform`, `GlobalTransform` and `TransformBundle` has been deprecated.
Use the associated constant `IDENTITY` instead.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Examples inconsistently use either `TAU`, `PI`, `FRAC_PI_2` or `FRAC_PI_4`.
Often in odd ways and without `use`ing the constants, making it difficult to parse.
* Use `PI` to specify angles.
* General code-quality improvements.
* Fix borked `hierarchy` example.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
*This PR description is an edited copy of #5007, written by @alice-i-cecile.*
# Objective
Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds.
While ergonomic, this results in several drawbacks:
* it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource
* it is challenging to discover if a type is intended to be used as a resource
* we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component).
* dependencies can use the same Rust type as a resource in invisibly conflicting ways
* raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values
* we cannot capture a definitive list of possible resources to display to users in an editor
## Notes to reviewers
* Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits.
*ira: My commits are not as well organized :')*
* I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does.
* I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981.
## Changelog
`Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro.
## Migration Guide
Add `#[derive(Resource)]` to all types you are using as a resource.
If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics.
`ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing.
Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead.
Co-authored-by: Alice <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Creating UI elements is very boilerplate-y with lots of indentation.
This PR aims to reduce boilerplate around creating text elements.
## Changelog
* Renamed `Text::with_section` to `from_section`.
It no longer takes a `TextAlignment` as argument, as the vast majority of cases left it `Default::default()`.
* Added `Text::from_sections` which creates a `Text` from a list of `TextSections`.
Reduces line-count and reduces indentation by one level.
* Added `Text::with_alignment`.
A builder style method for setting the `TextAlignment` of a `Text`.
* Added `TextSection::new`.
Does not reduce line count, but reduces character count and made it easier to read. No more `.to_string()` calls!
* Added `TextSection::from_style` which creates an empty `TextSection` with a style.
No more empty strings! Reduces indentation.
* Added `TextAlignment::CENTER` and friends.
* Added methods to `TextBundle`. `from_section`, `from_sections`, `with_text_alignment` and `with_style`.
## Note for reviewers.
Because of the nature of these changes I recommend setting diff view to 'split'.
~~Look for the book icon~~ cog in the top-left of the Files changed tab.
Have fun reviewing ❤️
<sup> >:D </sup>
## Migration Guide
`Text::with_section` was renamed to `from_section` and no longer takes a `TextAlignment` as argument.
Use `with_alignment` to set the alignment instead.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
- Add capability to use `Affine3A`s for some `GlobalTransform`s. This allows affine transformations that are not possible using a single `Transform` such as shear and non-uniform scaling along an arbitrary axis.
- Related to #1755 and #2026
## Solution
- `GlobalTransform` becomes an enum wrapping either a `Transform` or an `Affine3A`.
- The API of `GlobalTransform` is minimized to avoid inefficiency, and to make it clear that operations should be performed using the underlying data types.
- using `GlobalTransform::Affine3A` disables transform propagation, because the main use is for cases that `Transform`s cannot support.
---
## Changelog
- `GlobalTransform`s can optionally support any affine transformation using an `Affine3A`.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
Remove unnecessary calls to `iter()`/`iter_mut()`.
Mainly updates the use of queries in our code, docs, and examples.
```rust
// From
for _ in list.iter() {
for _ in list.iter_mut() {
// To
for _ in &list {
for _ in &mut list {
```
We already enable the pedantic lint [clippy::explicit_iter_loop](https://rust-lang.github.io/rust-clippy/stable/) inside of Bevy. However, this only warns for a few known types from the standard library.
## Note for reviewers
As you can see the additions and deletions are exactly equal.
Maybe give it a quick skim to check I didn't sneak in a crypto miner, but you don't have to torture yourself by reading every line.
I already experienced enough pain making this PR :)
Co-authored-by: devil-ira <justthecooldude@gmail.com>
## Objective
Implement absolute minimum viable product for the changes proposed in bevyengine/rfcs#53.
## Solution
- Remove public mutative access to `Parent` (Children is already publicly read-only). This includes public construction methods like `Copy`, `Clone`, and `Default`.
- Remove `PreviousParent`
- Remove `parent_update_system`
- Update all hierarchy related commands to immediately update both `Parent` and `Children` references.
## Remaining TODOs
- [ ] Update documentation for both `Parent` and `Children`. Discourage using `EntityCommands::remove`
- [x] Add `HierarchyEvent` to notify listeners of hierarchy updates. This is meant to replace listening on `PreviousParent`
## Followup
- These changes should be best moved to the hooks mentioned in #3742.
- Backing storage for both might be best moved to indexes mentioned in the same relations.
# Objective
Users often ask for help with rotations as they struggle with `Quat`s.
`Quat` is rather complex and has a ton of verbose methods.
## Solution
Add rotation helper methods to `Transform`.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
- Small bug in the example game given in examples/ecs/ecs_guide
Currently, if there are 2 players in this example game, the function exclusive_player_system can add a player with the name "Player 2". However, the name should be "Player 3". This PR fixes this. I also add a message to inform that a new player has arrived in the mock game.
Co-authored-by: Dilyan Kostov <dilyanks@amazon.com>
This adds "high level camera driven rendering" to Bevy. The goal is to give users more control over what gets rendered (and where) without needing to deal with render logic. This will make scenarios like "render to texture", "multiple windows", "split screen", "2d on 3d", "3d on 2d", "pass layering", and more significantly easier.
Here is an [example of a 2d render sandwiched between two 3d renders (each from a different perspective)](https://gist.github.com/cart/4fe56874b2e53bc5594a182fc76f4915):
Users can now spawn a camera, point it at a RenderTarget (a texture or a window), and it will "just work".
Rendering to a second window is as simple as spawning a second camera and assigning it to a specific window id:
```rust
// main camera (main window)
commands.spawn_bundle(Camera2dBundle::default());
// second camera (other window)
commands.spawn_bundle(Camera2dBundle {
camera: Camera {
target: RenderTarget::Window(window_id),
..default()
},
..default()
});
```
Rendering to a texture is as simple as pointing the camera at a texture:
```rust
commands.spawn_bundle(Camera2dBundle {
camera: Camera {
target: RenderTarget::Texture(image_handle),
..default()
},
..default()
});
```
Cameras now have a "render priority", which controls the order they are drawn in. If you want to use a camera's output texture as a texture in the main pass, just set the priority to a number lower than the main pass camera (which defaults to `0`).
```rust
// main pass camera with a default priority of 0
commands.spawn_bundle(Camera2dBundle::default());
commands.spawn_bundle(Camera2dBundle {
camera: Camera {
target: RenderTarget::Texture(image_handle.clone()),
priority: -1,
..default()
},
..default()
});
commands.spawn_bundle(SpriteBundle {
texture: image_handle,
..default()
})
```
Priority can also be used to layer to cameras on top of each other for the same RenderTarget. This is what "2d on top of 3d" looks like in the new system:
```rust
commands.spawn_bundle(Camera3dBundle::default());
commands.spawn_bundle(Camera2dBundle {
camera: Camera {
// this will render 2d entities "on top" of the default 3d camera's render
priority: 1,
..default()
},
..default()
});
```
There is no longer the concept of a global "active camera". Resources like `ActiveCamera<Camera2d>` and `ActiveCamera<Camera3d>` have been replaced with the camera-specific `Camera::is_active` field. This does put the onus on users to manage which cameras should be active.
Cameras are now assigned a single render graph as an "entry point", which is configured on each camera entity using the new `CameraRenderGraph` component. The old `PerspectiveCameraBundle` and `OrthographicCameraBundle` (generic on camera marker components like Camera2d and Camera3d) have been replaced by `Camera3dBundle` and `Camera2dBundle`, which set 3d and 2d default values for the `CameraRenderGraph` and projections.
```rust
// old 3d perspective camera
commands.spawn_bundle(PerspectiveCameraBundle::default())
// new 3d perspective camera
commands.spawn_bundle(Camera3dBundle::default())
```
```rust
// old 2d orthographic camera
commands.spawn_bundle(OrthographicCameraBundle::new_2d())
// new 2d orthographic camera
commands.spawn_bundle(Camera2dBundle::default())
```
```rust
// old 3d orthographic camera
commands.spawn_bundle(OrthographicCameraBundle::new_3d())
// new 3d orthographic camera
commands.spawn_bundle(Camera3dBundle {
projection: OrthographicProjection {
scale: 3.0,
scaling_mode: ScalingMode::FixedVertical,
..default()
}.into(),
..default()
})
```
Note that `Camera3dBundle` now uses a new `Projection` enum instead of hard coding the projection into the type. There are a number of motivators for this change: the render graph is now a part of the bundle, the way "generic bundles" work in the rust type system prevents nice `..default()` syntax, and changing projections at runtime is much easier with an enum (ex for editor scenarios). I'm open to discussing this choice, but I'm relatively certain we will all come to the same conclusion here. Camera2dBundle and Camera3dBundle are much clearer than being generic on marker components / using non-default constructors.
If you want to run a custom render graph on a camera, just set the `CameraRenderGraph` component:
```rust
commands.spawn_bundle(Camera3dBundle {
camera_render_graph: CameraRenderGraph::new(some_render_graph_name),
..default()
})
```
Just note that if the graph requires data from specific components to work (such as `Camera3d` config, which is provided in the `Camera3dBundle`), make sure the relevant components have been added.
Speaking of using components to configure graphs / passes, there are a number of new configuration options:
```rust
commands.spawn_bundle(Camera3dBundle {
camera_3d: Camera3d {
// overrides the default global clear color
clear_color: ClearColorConfig::Custom(Color::RED),
..default()
},
..default()
})
commands.spawn_bundle(Camera3dBundle {
camera_3d: Camera3d {
// disables clearing
clear_color: ClearColorConfig::None,
..default()
},
..default()
})
```
Expect to see more of the "graph configuration Components on Cameras" pattern in the future.
By popular demand, UI no longer requires a dedicated camera. `UiCameraBundle` has been removed. `Camera2dBundle` and `Camera3dBundle` now both default to rendering UI as part of their own render graphs. To disable UI rendering for a camera, disable it using the CameraUi component:
```rust
commands
.spawn_bundle(Camera3dBundle::default())
.insert(CameraUi {
is_enabled: false,
..default()
})
```
## Other Changes
* The separate clear pass has been removed. We should revisit this for things like sky rendering, but I think this PR should "keep it simple" until we're ready to properly support that (for code complexity and performance reasons). We can come up with the right design for a modular clear pass in a followup pr.
* I reorganized bevy_core_pipeline into Core2dPlugin and Core3dPlugin (and core_2d / core_3d modules). Everything is pretty much the same as before, just logically separate. I've moved relevant types (like Camera2d, Camera3d, Camera3dBundle, Camera2dBundle) into their relevant modules, which is what motivated this reorganization.
* I adapted the `scene_viewer` example (which relied on the ActiveCameras behavior) to the new system. I also refactored bits and pieces to be a bit simpler.
* All of the examples have been ported to the new camera approach. `render_to_texture` and `multiple_windows` are now _much_ simpler. I removed `two_passes` because it is less relevant with the new approach. If someone wants to add a new "layered custom pass with CameraRenderGraph" example, that might fill a similar niche. But I don't feel much pressure to add that in this pr.
* Cameras now have `target_logical_size` and `target_physical_size` fields, which makes finding the size of a camera's render target _much_ simpler. As a result, the `Assets<Image>` and `Windows` parameters were removed from `Camera::world_to_screen`, making that operation much more ergonomic.
* Render order ambiguities between cameras with the same target and the same priority now produce a warning. This accomplishes two goals:
1. Now that there is no "global" active camera, by default spawning two cameras will result in two renders (one covering the other). This would be a silent performance killer that would be hard to detect after the fact. By detecting ambiguities, we can provide a helpful warning when this occurs.
2. Render order ambiguities could result in unexpected / unpredictable render results. Resolving them makes sense.
## Follow Up Work
* Per-Camera viewports, which will make it possible to render to a smaller area inside of a RenderTarget (great for something like splitscreen)
* Camera-specific MSAA config (should use the same "overriding" pattern used for ClearColor)
* Graph Based Camera Ordering: priorities are simple, but they make complicated ordering constraints harder to express. We should consider adopting a "graph based" camera ordering model with "before" and "after" relationships to other cameras (or build it "on top" of the priority system).
* Consider allowing graphs to run subgraphs from any nest level (aka a global namespace for graphs). Right now the 2d and 3d graphs each need their own UI subgraph, which feels "fine" in the short term. But being able to share subgraphs between other subgraphs seems valuable.
* Consider splitting `bevy_core_pipeline` into `bevy_core_2d` and `bevy_core_3d` packages. Theres a shared "clear color" dependency here, which would need a new home.
# Objective
Fixes#3183. Requiring a `&TaskPool` parameter is sort of meaningless if the only correct one is to use the one provided by `Res<ComputeTaskPool>` all the time.
## Solution
Have `QueryState` save a clone of the `ComputeTaskPool` which is used for all `par_for_each` functions.
~~Adds a small overhead of the internal `Arc` clone as a part of the startup, but the ergonomics win should be well worth this hardly-noticable overhead.~~
Updated the docs to note that it will panic the task pool is not present as a resource.
# Future Work
If https://github.com/bevyengine/rfcs/pull/54 is approved, we can replace these resource lookups with a static function call instead to get the `ComputeTaskPool`.
---
## Changelog
Removed: The `task_pool` parameter of `Query(State)::par_for_each(_mut)`. These calls will use the `World`'s `ComputeTaskPool` resource instead.
## Migration Guide
The `task_pool` parameter for `Query(State)::par_for_each(_mut)` has been removed. Remove these parameters from all calls to these functions.
Before:
```rust
fn parallel_system(
task_pool: Res<ComputeTaskPool>,
query: Query<&MyComponent>,
) {
query.par_for_each(&task_pool, 32, |comp| {
...
});
}
```
After:
```rust
fn parallel_system(query: Query<&MyComponent>) {
query.par_for_each(32, |comp| {
...
});
}
```
If using `Query(State)` outside of a system run by the scheduler, you may need to manually configure and initialize a `ComputeTaskPool` as a resource in the `World`.
# Objective
- Coming from 7a596f1910 (r876310734)
- Simplify the examples regarding addition of `Msaa` Resource with default value.
## Solution
- Remove addition of `Msaa` Resource with default value from examples,
# Objective
Reduce the catch-all grab-bag of functionality in bevy_core by minimally splitting off time functionality into bevy_time. Functionality like that provided by #3002 would increase the complexity of bevy_time, so this is a good candidate for pulling into its own unit.
A step in addressing #2931 and splitting bevy_core into more specific locations.
## Solution
Pull the time module of bevy_core into a new crate, bevy_time.
# Migration guide
- Time related types (e.g. `Time`, `Timer`, `Stopwatch`, `FixedTimestep`, etc.) should be imported from `bevy::time::*` rather than `bevy::core::*`.
- If you were adding `CorePlugin` manually, you'll also want to add `TimePlugin` from `bevy::time`.
- The `bevy::core::CorePlugin::Time` system label is replaced with `bevy::time::TimeSystem`.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Provide a starting point for #3951, or a partial solution.
Providing a few comment blocks to discuss, and hopefully find better one in the process.
## Solution
Since I am pretty new to pretty much anything in this context, I figured I'd just start with a draft for some file level doc blocks. For some of them I found more relevant details (or at least things I considered interessting), for some others there is less.
## Changelog
- Moved some existing comments from main() functions in the 2d examples to the file header level
- Wrote some more comment blocks for most other 2d examples
TODO:
- [x] 2d/sprite_sheet, wasnt able to come up with something good yet
- [x] all other example groups...
Also: Please let me know if the commit style is okay, or to verbose. I could certainly squash these things, or add more details if needed.
I also hope its okay to raise this PR this early, with just a few files changed. Took me long enough and I dont wanted to let it go to waste because I lost motivation to do the whole thing. Additionally I am somewhat uncertain over the style and contents of the commets. So let me know what you thing please.
# Objective
`bevy_ecs` has large amounts of unsafe code which is hard to get right and makes it difficult to audit for soundness.
## Solution
Introduce lifetimed, type-erased pointers: `Ptr<'a>` `PtrMut<'a>` `OwningPtr<'a>'` and `ThinSlicePtr<'a, T>` which are newtypes around a raw pointer with a lifetime and conceptually representing strong invariants about the pointee and validity of the pointer.
The process of converting bevy_ecs to use these has already caught multiple cases of unsound behavior.
## Changelog
TL;DR for release notes: `bevy_ecs` now uses lifetimed, type-erased pointers internally, significantly improving safety and legibility without sacrificing performance. This should have approximately no end user impact, unless you were meddling with the (unfortunately public) internals of `bevy_ecs`.
- `Fetch`, `FilterFetch` and `ReadOnlyFetch` trait no longer have a `'state` lifetime
- this was unneeded
- `ReadOnly/Fetch` associated types on `WorldQuery` are now on a new `WorldQueryGats<'world>` trait
- was required to work around lack of Generic Associated Types (we wish to express `type Fetch<'a>: Fetch<'a>`)
- `derive(WorldQuery)` no longer requires `'w` lifetime on struct
- this was unneeded, and improves the end user experience
- `EntityMut::get_unchecked_mut` returns `&'_ mut T` not `&'w mut T`
- allows easier use of unsafe API with less footguns, and can be worked around via lifetime transmutery as a user
- `Bundle::from_components` now takes a `ctx` parameter to pass to the `FnMut` closure
- required because closure return types can't borrow from captures
- `Fetch::init` takes `&'world World`, `Fetch::set_archetype` takes `&'world Archetype` and `&'world Tables`, `Fetch::set_table` takes `&'world Table`
- allows types implementing `Fetch` to store borrows into world
- `WorldQuery` trait now has a `shrink` fn to shorten the lifetime in `Fetch::<'a>::Item`
- this works around lack of subtyping of assoc types, rust doesnt allow you to turn `<T as Fetch<'static>>::Item'` into `<T as Fetch<'a>>::Item'`
- `QueryCombinationsIter` requires this
- Most types implementing `Fetch` now have a lifetime `'w`
- allows the fetches to store borrows of world data instead of using raw pointers
## Migration guide
- `EntityMut::get_unchecked_mut` returns a more restricted lifetime, there is no general way to migrate this as it depends on your code
- `Bundle::from_components` implementations must pass the `ctx` arg to `func`
- `Bundle::from_components` callers have to use a fn arg instead of closure captures for borrowing from world
- Remove lifetime args on `derive(WorldQuery)` structs as it is nonsensical
- `<Q as WorldQuery>::ReadOnly/Fetch` should be changed to either `RO/QueryFetch<'world>` or `<Q as WorldQueryGats<'world>>::ReadOnly/Fetch`
- `<F as Fetch<'w, 's>>` should be changed to `<F as Fetch<'w>>`
- Change the fn sigs of `Fetch::init/set_archetype/set_table` to match respective trait fn sigs
- Implement the required `fn shrink` on any `WorldQuery` implementations
- Move assoc types `Fetch` and `ReadOnlyFetch` on `WorldQuery` impls to `WorldQueryGats` impls
- Pass an appropriate `'world` lifetime to whatever fetch struct you are for some reason using
### Type inference regression
in some cases rustc may give spurrious errors when attempting to infer the `F` parameter on a query/querystate this can be fixed by manually specifying the type, i.e. `QueryState:🆕:<_, ()>(world)`. The error is rather confusing:
```rust=
error[E0271]: type mismatch resolving `<() as Fetch<'_>>::Item == bool`
--> crates/bevy_pbr/src/render/light.rs:1413:30
|
1413 | main_view_query: QueryState::new(world),
| ^^^^^^^^^^^^^^^ expected `bool`, found `()`
|
= note: required because of the requirements on the impl of `for<'x> FilterFetch<'x>` for `<() as WorldQueryGats<'x>>::Fetch`
note: required by a bound in `bevy_ecs::query::QueryState::<Q, F>::new`
--> crates/bevy_ecs/src/query/state.rs:49:32
|
49 | for<'x> QueryFetch<'x, F>: FilterFetch<'x>,
| ^^^^^^^^^^^^^^^ required by this bound in `bevy_ecs::query::QueryState::<Q, F>::new`
```
---
Made with help from @BoxyUwU and @alice-i-cecile
Co-authored-by: Boxy <supbscripter@gmail.com>
# Objective
- Closes#335.
- Related #4285.
- Part of the splitting process of #3503.
## Solution
- Move `Rect` to `bevy_ui` and rename it to `UiRect`.
## Reasons
- `Rect` is only used in `bevy_ui` and therefore calling it `UiRect` makes the intent clearer.
- We have two types that are called `Rect` currently and it's missleading (see `bevy_sprite::Rect` and #335).
- Discussion in #3503.
## Changelog
### Changed
- The `Rect` type got moved from `bevy_math` to `bevy_ui` and renamed to `UiRect`.
## Migration Guide
- The `Rect` type got renamed to `UiRect`. To migrate you just have to change every occurrence of `Rect` to `UiRect`.
Co-authored-by: KDecay <KDecayMusic@protonmail.com>
Remove the 'chaining' api, as it's peculiar
~~Implement the label traits for `Box<dyn ThatTrait>` (n.b. I'm not confident about this change, but it was the quickest path to not regressing)~~
Remove the need for '`.system`' when using run criteria piping
# Objective
- `Local`s can no longer be accessed outside of their creating system, but these docs say they can be.
- There's also little reason to have a pure wrapper type for `Local`s; they can just use the real type. The parameter name should be sufficiently documenting.
