764be9199c
8 Commits
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38c3423693
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Event Split: Event , EntityEvent , and BufferedEvent (#19647)
# Objective Closes #19564. The current `Event` trait looks like this: ```rust pub trait Event: Send + Sync + 'static { type Traversal: Traversal<Self>; const AUTO_PROPAGATE: bool = false; fn register_component_id(world: &mut World) -> ComponentId { ... } fn component_id(world: &World) -> Option<ComponentId> { ... } } ``` The `Event` trait is used by both buffered events (`EventReader`/`EventWriter`) and observer events. If they are observer events, they can optionally be targeted at specific `Entity`s or `ComponentId`s, and can even be propagated to other entities. However, there has long been a desire to split the trait semantically for a variety of reasons, see #14843, #14272, and #16031 for discussion. Some reasons include: - It's very uncommon to use a single event type as both a buffered event and targeted observer event. They are used differently and tend to have distinct semantics. - A common footgun is using buffered events with observers or event readers with observer events, as there is no type-level error that prevents this kind of misuse. - #19440 made `Trigger::target` return an `Option<Entity>`. This *seriously* hurts ergonomics for the general case of entity observers, as you need to `.unwrap()` each time. If we could statically determine whether the event is expected to have an entity target, this would be unnecessary. There's really two main ways that we can categorize events: push vs. pull (i.e. "observer event" vs. "buffered event") and global vs. targeted: | | Push | Pull | | ------------ | --------------- | --------------------------- | | **Global** | Global observer | `EventReader`/`EventWriter` | | **Targeted** | Entity observer | - | There are many ways to approach this, each with their tradeoffs. Ultimately, we kind of want to split events both ways: - A type-level distinction between observer events and buffered events, to prevent people from using the wrong kind of event in APIs - A statically designated entity target for observer events to avoid accidentally using untargeted events for targeted APIs This PR achieves these goals by splitting event traits into `Event`, `EntityEvent`, and `BufferedEvent`, with `Event` being the shared trait implemented by all events. ## `Event`, `EntityEvent`, and `BufferedEvent` `Event` is now a very simple trait shared by all events. ```rust pub trait Event: Send + Sync + 'static { // Required for observer APIs fn register_component_id(world: &mut World) -> ComponentId { ... } fn component_id(world: &World) -> Option<ComponentId> { ... } } ``` You can call `trigger` for *any* event, and use a global observer for listening to the event. ```rust #[derive(Event)] struct Speak { message: String, } // ... app.add_observer(|trigger: On<Speak>| { println!("{}", trigger.message); }); // ... commands.trigger(Speak { message: "Y'all like these reworked events?".to_string(), }); ``` To allow an event to be targeted at entities and even propagated further, you can additionally implement the `EntityEvent` trait: ```rust pub trait EntityEvent: Event { type Traversal: Traversal<Self>; const AUTO_PROPAGATE: bool = false; } ``` This lets you call `trigger_targets`, and to use targeted observer APIs like `EntityCommands::observe`: ```rust #[derive(Event, EntityEvent)] #[entity_event(traversal = &'static ChildOf, auto_propagate)] struct Damage { amount: f32, } // ... let enemy = commands.spawn((Enemy, Health(100.0))).id(); // Spawn some armor as a child of the enemy entity. // When the armor takes damage, it will bubble the event up to the enemy. let armor_piece = commands .spawn((ArmorPiece, Health(25.0), ChildOf(enemy))) .observe(|trigger: On<Damage>, mut query: Query<&mut Health>| { // Note: `On::target` only exists because this is an `EntityEvent`. let mut health = query.get(trigger.target()).unwrap(); health.0 -= trigger.amount(); }); commands.trigger_targets(Damage { amount: 10.0 }, armor_piece); ``` > [!NOTE] > You *can* still also trigger an `EntityEvent` without targets using `trigger`. We probably *could* make this an either-or thing, but I'm not sure that's actually desirable. To allow an event to be used with the buffered API, you can implement `BufferedEvent`: ```rust pub trait BufferedEvent: Event {} ``` The event can then be used with `EventReader`/`EventWriter`: ```rust #[derive(Event, BufferedEvent)] struct Message(String); fn write_hello(mut writer: EventWriter<Message>) { writer.write(Message("I hope these examples are alright".to_string())); } fn read_messages(mut reader: EventReader<Message>) { // Process all buffered events of type `Message`. for Message(message) in reader.read() { println!("{message}"); } } ``` In summary: - Need a basic event you can trigger and observe? Derive `Event`! - Need the event to be targeted at an entity? Derive `EntityEvent`! - Need the event to be buffered and support the `EventReader`/`EventWriter` API? Derive `BufferedEvent`! ## Alternatives I'll now cover some of the alternative approaches I have considered and briefly explored. I made this section collapsible since it ended up being quite long :P <details> <summary>Expand this to see alternatives</summary> ### 1. Unified `Event` Trait One option is not to have *three* separate traits (`Event`, `EntityEvent`, `BufferedEvent`), and to instead just use associated constants on `Event` to determine whether an event supports targeting and buffering or not: ```rust pub trait Event: Send + Sync + 'static { type Traversal: Traversal<Self>; const AUTO_PROPAGATE: bool = false; const TARGETED: bool = false; const BUFFERED: bool = false; fn register_component_id(world: &mut World) -> ComponentId { ... } fn component_id(world: &World) -> Option<ComponentId> { ... } } ``` Methods can then use bounds like `where E: Event<TARGETED = true>` or `where E: Event<BUFFERED = true>` to limit APIs to specific kinds of events. This would keep everything under one `Event` trait, but I don't think it's necessarily a good idea. It makes APIs harder to read, and docs can't easily refer to specific types of events. You can also create weird invariants: what if you specify `TARGETED = false`, but have `Traversal` and/or `AUTO_PROPAGATE` enabled? ### 2. `Event` and `Trigger` Another option is to only split the traits between buffered events and observer events, since that is the main thing people have been asking for, and they have the largest API difference. If we did this, I think we would need to make the terms *clearly* separate. We can't really use `Event` and `BufferedEvent` as the names, since it would be strange that `BufferedEvent` doesn't implement `Event`. Something like `ObserverEvent` and `BufferedEvent` could work, but it'd be more verbose. For this approach, I would instead keep `Event` for the current `EventReader`/`EventWriter` API, and call the observer event a `Trigger`, since the "trigger" terminology is already used in the observer context within Bevy (both as a noun and a verb). This is also what a long [bikeshed on Discord](https://discord.com/channels/691052431525675048/749335865876021248/1298057661878898791) seemed to land on at the end of last year. ```rust // For `EventReader`/`EventWriter` pub trait Event: Send + Sync + 'static {} // For observers pub trait Trigger: Send + Sync + 'static { type Traversal: Traversal<Self>; const AUTO_PROPAGATE: bool = false; const TARGETED: bool = false; fn register_component_id(world: &mut World) -> ComponentId { ... } fn component_id(world: &World) -> Option<ComponentId> { ... } } ``` The problem is that "event" is just a really good term for something that "happens". Observers are rapidly becoming the more prominent API, so it'd be weird to give them the `Trigger` name and leave the good `Event` name for the less common API. So, even though a split like this seems neat on the surface, I think it ultimately wouldn't really work. We want to keep the `Event` name for observer events, and there is no good alternative for the buffered variant. (`Message` was suggested, but saying stuff like "sends a collision message" is weird.) ### 3. `GlobalEvent` + `TargetedEvent` What if instead of focusing on the buffered vs. observed split, we *only* make a distinction between global and targeted events? ```rust // A shared event trait to allow global observers to work pub trait Event: Send + Sync + 'static { fn register_component_id(world: &mut World) -> ComponentId { ... } fn component_id(world: &World) -> Option<ComponentId> { ... } } // For buffered events and non-targeted observer events pub trait GlobalEvent: Event {} // For targeted observer events pub trait TargetedEvent: Event { type Traversal: Traversal<Self>; const AUTO_PROPAGATE: bool = false; } ``` This is actually the first approach I implemented, and it has the neat characteristic that you can only use non-targeted APIs like `trigger` with a `GlobalEvent` and targeted APIs like `trigger_targets` with a `TargetedEvent`. You have full control over whether the entity should or should not have a target, as they are fully distinct at the type-level. However, there's a few problems: - There is no type-level indication of whether a `GlobalEvent` supports buffered events or just non-targeted observer events - An `Event` on its own does literally nothing, it's just a shared trait required to make global observers accept both non-targeted and targeted events - If an event is both a `GlobalEvent` and `TargetedEvent`, global observers again have ambiguity on whether an event has a target or not, undermining some of the benefits - The names are not ideal ### 4. `Event` and `EntityEvent` We can fix some of the problems of Alternative 3 by accepting that targeted events can also be used in non-targeted contexts, and simply having the `Event` and `EntityEvent` traits: ```rust // For buffered events and non-targeted observer events pub trait Event: Send + Sync + 'static { fn register_component_id(world: &mut World) -> ComponentId { ... } fn component_id(world: &World) -> Option<ComponentId> { ... } } // For targeted observer events pub trait EntityEvent: Event { type Traversal: Traversal<Self>; const AUTO_PROPAGATE: bool = false; } ``` This is essentially identical to this PR, just without a dedicated `BufferedEvent`. The remaining major "problem" is that there is still zero type-level indication of whether an `Event` event *actually* supports the buffered API. This leads us to the solution proposed in this PR, using `Event`, `EntityEvent`, and `BufferedEvent`. </details> ## Conclusion The `Event` + `EntityEvent` + `BufferedEvent` split proposed in this PR aims to solve all the common problems with Bevy's current event model while keeping the "weirdness" factor minimal. It splits in terms of both the push vs. pull *and* global vs. targeted aspects, while maintaining a shared concept for an "event". ### Why I Like This - The term "event" remains as a single concept for all the different kinds of events in Bevy. - Despite all event types being "events", they use fundamentally different APIs. Instead of assuming that you can use an event type with any pattern (when only one is typically supported), you explicitly opt in to each one with dedicated traits. - Using separate traits for each type of event helps with documentation and clearer function signatures. - I can safely make assumptions on expected usage. - If I see that an event is an `EntityEvent`, I can assume that I can use `observe` on it and get targeted events. - If I see that an event is a `BufferedEvent`, I can assume that I can use `EventReader` to read events. - If I see both `EntityEvent` and `BufferedEvent`, I can assume that both APIs are supported. In summary: This allows for a unified concept for events, while limiting the different ways to use them with opt-in traits. No more guess-work involved when using APIs. ### Problems? - Because `BufferedEvent` implements `Event` (for more consistent semantics etc.), you can still use all buffered events for non-targeted observers. I think this is fine/good. The important part is that if you see that an event implements `BufferedEvent`, you know that the `EventReader`/`EventWriter` API should be supported. Whether it *also* supports other APIs is secondary. - I currently only support `trigger_targets` for an `EntityEvent`. However, you can technically target components too, without targeting any entities. I consider that such a niche and advanced use case that it's not a huge problem to only support it for `EntityEvent`s, but we could also split `trigger_targets` into `trigger_entities` and `trigger_components` if we wanted to (or implement components as entities :P). - You can still trigger an `EntityEvent` *without* targets. I consider this correct, since `Event` implements the non-targeted behavior, and it'd be weird if implementing another trait *removed* behavior. However, it does mean that global observers for entity events can technically return `Entity::PLACEHOLDER` again (since I got rid of the `Option<Entity>` added in #19440 for ergonomics). I think that's enough of an edge case that it's not a huge problem, but it is worth keeping in mind. - ~~Deriving both `EntityEvent` and `BufferedEvent` for the same type currently duplicates the `Event` implementation, so you instead need to manually implement one of them.~~ Changed to always requiring `Event` to be derived. ## Related Work There are plans to implement multi-event support for observers, especially for UI contexts. [Cart's example](https://github.com/bevyengine/bevy/issues/14649#issuecomment-2960402508) API looked like this: ```rust // Truncated for brevity trigger: Trigger<( OnAdd<Pressed>, OnRemove<Pressed>, OnAdd<InteractionDisabled>, OnRemove<InteractionDisabled>, OnInsert<Hovered>, )>, ``` I believe this shouldn't be in conflict with this PR. If anything, this PR might *help* achieve the multi-event pattern for entity observers with fewer footguns: by statically enforcing that all of these events are `EntityEvent`s in the context of `EntityCommands::observe`, we can avoid misuse or weird cases where *some* events inside the trigger are targeted while others are not. |
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5f86668bbb
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Renamed EventWriter::send methods to write . (#17977)
Fixes #17856. ## Migration Guide - `EventWriter::send` has been renamed to `EventWriter::write`. - `EventWriter::send_batch` has been renamed to `EventWriter::write_batch`. - `EventWriter::send_default` has been renamed to `EventWriter::write_default`. --------- Co-authored-by: François Mockers <mockersf@gmail.com> |
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ed151e756c
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Migrate audio to required components (#15573)
# Objective What's that? Another PR for the grand migration to required components? This time, audio! ## Solution Deprecate `AudioSourceBundle`, `AudioBundle`, and `PitchBundle`, as per the [chosen proposal](https://hackmd.io/@bevy/required_components/%2Fzxgp-zMMRUCdT7LY1ZDQwQ). However, we cannot call the component `AudioSource`, because that's what the stored asset is called. I deliberated on a few names, like `AudioHandle`, or even just `Audio`, but landed on `AudioPlayer`, since it's probably the most accurate and "nice" name for this. Open to alternatives though. --- ## Migration Guide Replace all insertions of `AudioSoucreBundle`, `AudioBundle`, and `PitchBundle` with the `AudioPlayer` component. The other components required by it will now be inserted automatically. In cases where the generics cannot be inferred, you may need to specify them explicitly. For example: ```rust commands.spawn(AudioPlayer::<AudioSource>(asset_server.load("sounds/sick_beats.ogg"))); ``` |
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29508f065f
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Fix floating point math (#15239)
# Objective - Fixes #15236 ## Solution - Use bevy_math::ops instead of std floating point operations. ## Testing - Did you test these changes? If so, how? Unit tests and `cargo run -p ci -- test` - How can other people (reviewers) test your changes? Is there anything specific they need to know? Execute `cargo run -p ci -- test` on Windows. - If relevant, what platforms did you test these changes on, and are there any important ones you can't test? Windows ## Migration Guide - Not a breaking change - Projects should use bevy math where applicable --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: IQuick 143 <IQuick143cz@gmail.com> Co-authored-by: Joona Aalto <jondolf.dev@gmail.com> |
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ced216f59a
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Update winit dependency to 0.29 (#10702)
# Objective - Update winit dependency to 0.29 ## Changelog ### KeyCode changes - Removed `ScanCode`, as it was [replaced by KeyCode](https://github.com/rust-windowing/winit/blob/master/CHANGELOG.md#0292). - `ReceivedCharacter.char` is now a `SmolStr`, [relevant doc](https://docs.rs/winit/latest/winit/event/struct.KeyEvent.html#structfield.text). - Changed most `KeyCode` values, and added more. KeyCode has changed meaning. With this PR, it refers to physical position on keyboard rather than the printed letter on keyboard keys. In practice this means: - On QWERTY keyboard layouts, nothing changes - On any other keyboard layout, `KeyCode` no longer reflects the label on key. - This is "good". In bevy 0.12, when you used WASD for movement, users with non-QWERTY keyboards couldn't play your game! This was especially bad for non-latin keyboards. Now, WASD represents the physical keys. A French player will press the ZQSD keys, which are near each other, Kyrgyz players will use "Цфыв". - This is "bad" as well. You can't know in advance what the label of the key for input is. Your UI says "press WASD to move", even if in reality, they should be pressing "ZQSD" or "Цфыв". You also no longer can use `KeyCode` for text inputs. In any case, it was a pretty bad API for text input. You should use `ReceivedCharacter` now instead. ### Other changes - Use `web-time` rather than `instant` crate. (https://github.com/rust-windowing/winit/pull/2836) - winit did split `run_return` in `run_onDemand` and `pump_events`, I did the same change in bevy_winit and used `pump_events`. - Removed `return_from_run` from `WinitSettings` as `winit::run` now returns on supported platforms. - I left the example "return_after_run" as I think it's still useful. - This winit change is done partly to allow to create a new window after quitting all windows: https://github.com/emilk/egui/issues/1918 ; this PR doesn't address. - added `width` and `height` properties in the `canvas` from wasm example (https://github.com/bevyengine/bevy/pull/10702#discussion_r1420567168) ## Known regressions (important follow ups?) - Provide an API for reacting when a specific key from current layout was released. - possible solutions: use winit::Key from winit::KeyEvent ; mapping between KeyCode and Key ; or . - We don't receive characters through alt+numpad (e.g. alt + 151 = "ù") anymore ; reproduced on winit example "ime". maybe related to https://github.com/rust-windowing/winit/issues/2945 - (windows) Window content doesn't refresh at all when resizing. By reading https://github.com/rust-windowing/winit/issues/2900 ; I suspect we should just fire a `window.request_redraw();` from `AboutToWait`, and handle actual redrawing within `RedrawRequested`. I'm not sure how to move all that code so I'd appreciate it to be a follow up. - (windows) unreleased winit fix for using set_control_flow in AboutToWait https://github.com/rust-windowing/winit/issues/3215 ; ⚠️ I'm not sure what the implications are, but that feels bad 🤔 ## Follow up I'd like to avoid bloating this PR, here are a few follow up tasks worthy of a separate PR, or new issue to track them once this PR is closed, as they would either complicate reviews, or at risk of being controversial: - remove CanvasParentResizePlugin (https://github.com/bevyengine/bevy/pull/10702#discussion_r1417068856) - avoid mentionning explicitly winit in docs from bevy_window ? - NamedKey integration on bevy_input: https://github.com/rust-windowing/winit/pull/3143 introduced a new NamedKey variant. I implemented it only on the converters but we'd benefit making the same changes to bevy_input. - Add more info in KeyboardInput https://github.com/bevyengine/bevy/pull/10702#pullrequestreview-1748336313 - https://github.com/bevyengine/bevy/pull/9905 added a workaround on a bug allegedly fixed by winit 0.29. We should check if it's still necessary. - update to raw_window_handle 0.6 - blocked by wgpu - Rename `KeyCode` to `PhysicalKeyCode` https://github.com/bevyengine/bevy/pull/10702#discussion_r1404595015 - remove `instant` dependency, [replaced by](https://github.com/rust-windowing/winit/pull/2836) `web_time`), we'd need to update to : - fastrand >= 2.0 - [`async-executor`](https://github.com/smol-rs/async-executor) >= 1.7 - [`futures-lite`](https://github.com/smol-rs/futures-lite) >= 2.0 - Verify license, see [discussion](https://github.com/bevyengine/bevy/pull/8745#discussion_r1402439800) - we might be missing a short notice or description of changes made - Consider using https://github.com/rust-windowing/cursor-icon directly rather than vendoring it in bevy. - investigate [this unwrap](https://github.com/bevyengine/bevy/pull/8745#discussion_r1387044986) (`winit_window.canvas().unwrap();`) - Use more good things about winit's update - https://github.com/bevyengine/bevy/pull/10689#issuecomment-1823560428 ## Migration Guide This PR should have one. |
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1f97717a3d
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Rename Input to ButtonInput (#10859)
# Objective - Resolves #10853 ## Solution - ~~Changed the name of `Input` struct to `PressableInput`.~~ - Changed the name of `Input` struct to `ButtonInput`. ## Migration Guide - Breaking Change: Users need to rename `Input` to `ButtonInput` in their projects. |
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42e6dc8987
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Refactor EventReader::iter to read (#9631)
# Objective - The current `EventReader::iter` has been determined to cause confusion among new Bevy users. It was suggested by @JoJoJet to rename the method to better clarify its usage. - Solves #9624 ## Solution - Rename `EventReader::iter` to `EventReader::read`. - Rename `EventReader::iter_with_id` to `EventReader::read_with_id`. - Rename `ManualEventReader::iter` to `ManualEventReader::read`. - Rename `ManualEventReader::iter_with_id` to `ManualEventReader::read_with_id`. --- ## Changelog - `EventReader::iter` has been renamed to `EventReader::read`. - `EventReader::iter_with_id` has been renamed to `EventReader::read_with_id`. - `ManualEventReader::iter` has been renamed to `ManualEventReader::read`. - `ManualEventReader::iter_with_id` has been renamed to `ManualEventReader::read_with_id`. - Deprecated `EventReader::iter` - Deprecated `EventReader::iter_with_id` - Deprecated `ManualEventReader::iter` - Deprecated `ManualEventReader::iter_with_id` ## Migration Guide - Existing usages of `EventReader::iter` and `EventReader::iter_with_id` will have to be changed to `EventReader::read` and `EventReader::read_with_id` respectively. - Existing usages of `ManualEventReader::iter` and `ManualEventReader::iter_with_id` will have to be changed to `ManualEventReader::read` and `ManualEventReader::read_with_id` respectively. |
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fb9c5a6cbb
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Added Pitch as an alternative sound source (#9225)
# Objective My attempt at implementing #7515 ## Solution Added struct `Pitch` and implemented on it `Source` trait. ## Changelog ### Added - File pitch.rs to bevy_audio crate - Struct `Pitch` and type aliases for `AudioSourceBundle<Pitch>` and `SpatialAudioSourceBundle<Pitch>` - New example showing how to use `PitchBundle` ### Changed - `AudioPlugin` now adds system for `Pitch` audio --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |