ed7b366b24
235 Commits
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ed7b366b24
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Deprecate insert_or_spawn function family (#18147)
# Objective Based on #18054, this PR builds on #18035 to deprecate: - `Commands::insert_or_spawn_batch` - `Entities::alloc_at_without_replacement` - `Entities::alloc_at` - `World::insert_or_spawn_batch` - `World::insert_or_spawn_batch_with_caller` ## Testing Just deprecation, so no new tests. Note that as of writing #18035 is still under testing and review. ## Open Questions - [x] Should `entity::AllocAtWithoutReplacement` be deprecated? It is internal and only used in `Entities::alloc_at_without_replacement`. **EDIT:** Now deprecated. ## Migration Guide The following functions have been deprecated: - `Commands::insert_or_spawn_batch` - `World::insert_or_spawn_batch` - `World::insert_or_spawn_batch_with_caller` These functions, when used incorrectly, can cause major performance problems and are generally viewed as anti-patterns and foot guns. These are planned to be removed altogether in 0.17. Instead of these functions consider doing one of the following: Option A) Instead of despawing entities and re-spawning them at a particular id, insert the new `Disabled` component without despawning the entity, and use `try_insert_batch` or `insert_batch` and remove `Disabled` instead of re-spawning it. Option B) Instead of giving special meaning to an entity id, simply use `spawn_batch` and ensure entity references are valid when despawning. --------- Co-authored-by: JaySpruce <jsprucebruce@gmail.com> Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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06cb5c5fd9
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Fix Component require() IDE integration (#18165)
# Objective Component `require()` IDE integration is fully broken, as of #16575. ## Solution This reverts us back to the previous "put the docs on Component trait" impl. This _does_ reduce the accessibility of the required components in rust docs, but the complete erasure of "required component IDE experience" is not worth the price of slightly increased prominence of requires in docs. Additionally, Rust Analyzer has recently started including derive attributes in suggestions, so we aren't losing that benefit of the proc_macro attribute impl. |
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5241e09671
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Upgrade to Rust Edition 2024 (#17967)
# Objective - Fixes #17960 ## Solution - Followed the [edition upgrade guide](https://doc.rust-lang.org/edition-guide/editions/transitioning-an-existing-project-to-a-new-edition.html) ## Testing - CI --- ## Summary of Changes ### Documentation Indentation When using lists in documentation, proper indentation is now linted for. This means subsequent lines within the same list item must start at the same indentation level as the item. ```rust /* Valid */ /// - Item 1 /// Run-on sentence. /// - Item 2 struct Foo; /* Invalid */ /// - Item 1 /// Run-on sentence. /// - Item 2 struct Foo; ``` ### Implicit `!` to `()` Conversion `!` (the never return type, returned by `panic!`, etc.) no longer implicitly converts to `()`. This is particularly painful for systems with `todo!` or `panic!` statements, as they will no longer be functions returning `()` (or `Result<()>`), making them invalid systems for functions like `add_systems`. The ideal fix would be to accept functions returning `!` (or rather, _not_ returning), but this is blocked on the [stabilisation of the `!` type itself](https://doc.rust-lang.org/std/primitive.never.html), which is not done. The "simple" fix would be to add an explicit `-> ()` to system signatures (e.g., `|| { todo!() }` becomes `|| -> () { todo!() }`). However, this is _also_ banned, as there is an existing lint which (IMO, incorrectly) marks this as an unnecessary annotation. So, the "fix" (read: workaround) is to put these kinds of `|| -> ! { ... }` closuers into variables and give the variable an explicit type (e.g., `fn()`). ```rust // Valid let system: fn() = || todo!("Not implemented yet!"); app.add_systems(..., system); // Invalid app.add_systems(..., || todo!("Not implemented yet!")); ``` ### Temporary Variable Lifetimes The order in which temporary variables are dropped has changed. The simple fix here is _usually_ to just assign temporaries to a named variable before use. ### `gen` is a keyword We can no longer use the name `gen` as it is reserved for a future generator syntax. This involved replacing uses of the name `gen` with `r#gen` (the raw-identifier syntax). ### Formatting has changed Use statements have had the order of imports changed, causing a substantial +/-3,000 diff when applied. For now, I have opted-out of this change by amending `rustfmt.toml` ```toml style_edition = "2021" ``` This preserves the original formatting for now, reducing the size of this PR. It would be a simple followup to update this to 2024 and run `cargo fmt`. ### New `use<>` Opt-Out Syntax Lifetimes are now implicitly included in RPIT types. There was a handful of instances where it needed to be added to satisfy the borrow checker, but there may be more cases where it _should_ be added to avoid breakages in user code. ### `MyUnitStruct { .. }` is an invalid pattern Previously, you could match against unit structs (and unit enum variants) with a `{ .. }` destructuring. This is no longer valid. ### Pretty much every use of `ref` and `mut` are gone Pattern binding has changed to the point where these terms are largely unused now. They still serve a purpose, but it is far more niche now. ### `iter::repeat(...).take(...)` is bad New lint recommends using the more explicit `iter::repeat_n(..., ...)` instead. ## Migration Guide The lifetimes of functions using return-position impl-trait (RPIT) are likely _more_ conservative than they had been previously. If you encounter lifetime issues with such a function, please create an issue to investigate the addition of `+ use<...>`. ## Notes - Check the individual commits for a clearer breakdown for what _actually_ changed. --------- Co-authored-by: François Mockers <francois.mockers@vleue.com> |
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ea578415e1
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Improved Spawn APIs and Bundle Effects (#17521)
## Objective A major critique of Bevy at the moment is how boilerplatey it is to compose (and read) entity hierarchies: ```rust commands .spawn(Foo) .with_children(|p| { p.spawn(Bar).with_children(|p| { p.spawn(Baz); }); p.spawn(Bar).with_children(|p| { p.spawn(Baz); }); }); ``` There is also currently no good way to statically define and return an entity hierarchy from a function. Instead, people often do this "internally" with a Commands function that returns nothing, making it impossible to spawn the hierarchy in other cases (direct World spawns, ChildSpawner, etc). Additionally, because this style of API results in creating the hierarchy bits _after_ the initial spawn of a bundle, it causes ECS archetype changes (and often expensive table moves). Because children are initialized after the fact, we also can't count them to pre-allocate space. This means each time a child inserts itself, it has a high chance of overflowing the currently allocated capacity in the `RelationshipTarget` collection, causing literal worst-case reallocations. We can do better! ## Solution The Bundle trait has been extended to support an optional `BundleEffect`. This is applied directly to World immediately _after_ the Bundle has fully inserted. Note that this is [intentionally](https://github.com/bevyengine/bevy/discussions/16920) _not done via a deferred Command_, which would require repeatedly copying each remaining subtree of the hierarchy to a new command as we walk down the tree (_not_ good performance). This allows us to implement the new `SpawnRelated` trait for all `RelationshipTarget` impls, which looks like this in practice: ```rust world.spawn(( Foo, Children::spawn(( Spawn(( Bar, Children::spawn(Spawn(Baz)), )), Spawn(( Bar, Children::spawn(Spawn(Baz)), )), )) )) ``` `Children::spawn` returns `SpawnRelatedBundle<Children, L: SpawnableList>`, which is a `Bundle` that inserts `Children` (preallocated to the size of the `SpawnableList::size_hint()`). `Spawn<B: Bundle>(pub B)` implements `SpawnableList` with a size of 1. `SpawnableList` is also implemented for tuples of `SpawnableList` (same general pattern as the Bundle impl). There are currently three built-in `SpawnableList` implementations: ```rust world.spawn(( Foo, Children::spawn(( Spawn(Name::new("Child1")), SpawnIter(["Child2", "Child3"].into_iter().map(Name::new), SpawnWith(|parent: &mut ChildSpawner| { parent.spawn(Name::new("Child4")); parent.spawn(Name::new("Child5")); }) )), )) ``` We get the benefits of "structured init", but we have nice flexibility where it is required! Some readers' first instinct might be to try to remove the need for the `Spawn` wrapper. This is impossible in the Rust type system, as a tuple of "child Bundles to be spawned" and a "tuple of Components to be added via a single Bundle" is ambiguous in the Rust type system. There are two ways to resolve that ambiguity: 1. By adding support for variadics to the Rust type system (removing the need for nested bundles). This is out of scope for this PR :) 2. Using wrapper types to resolve the ambiguity (this is what I did in this PR). For the single-entity spawn cases, `Children::spawn_one` does also exist, which removes the need for the wrapper: ```rust world.spawn(( Foo, Children::spawn_one(Bar), )) ``` ## This works for all Relationships This API isn't just for `Children` / `ChildOf` relationships. It works for any relationship type, and they can be mixed and matched! ```rust world.spawn(( Foo, Observers::spawn(( Spawn(Observer::new(|trigger: Trigger<FuseLit>| {})), Spawn(Observer::new(|trigger: Trigger<Exploded>| {})), )), OwnerOf::spawn(Spawn(Bar)) Children::spawn(Spawn(Baz)) )) ``` ## Macros While `Spawn` is necessary to satisfy the type system, we _can_ remove the need to express it via macros. The example above can be expressed more succinctly using the new `children![X]` macro, which internally produces `Children::spawn(Spawn(X))`: ```rust world.spawn(( Foo, children![ ( Bar, children![Baz], ), ( Bar, children![Baz], ), ] )) ``` There is also a `related!` macro, which is a generic version of the `children!` macro that supports any relationship type: ```rust world.spawn(( Foo, related!(Children[ ( Bar, related!(Children[Baz]), ), ( Bar, related!(Children[Baz]), ), ]) )) ``` ## Returning Hierarchies from Functions Thanks to these changes, the following pattern is now possible: ```rust fn button(text: &str, color: Color) -> impl Bundle { ( Node { width: Val::Px(300.), height: Val::Px(100.), ..default() }, BackgroundColor(color), children![ Text::new(text), ] ) } fn ui() -> impl Bundle { ( Node { width: Val::Percent(100.0), height: Val::Percent(100.0), ..default(), }, children![ button("hello", BLUE), button("world", RED), ] ) } // spawn from a system fn system(mut commands: Commands) { commands.spawn(ui()); } // spawn directly on World world.spawn(ui()); ``` ## Additional Changes and Notes * `Bundle::from_components` has been split out into `BundleFromComponents::from_components`, enabling us to implement `Bundle` for types that cannot be "taken" from the ECS (such as the new `SpawnRelatedBundle`). * The `NoBundleEffect` trait (which implements `BundleEffect`) is implemented for empty tuples (and tuples of empty tuples), which allows us to constrain APIs to only accept bundles that do not have effects. This is critical because the current batch spawn APIs cannot efficiently apply BundleEffects in their current form (as doing so in-place could invalidate the cached raw pointers). We could consider allocating a buffer of the effects to be applied later, but that does have performance implications that could offset the balance and value of the batched APIs (and would likely require some refactors to the underlying code). I've decided to be conservative here. We can consider relaxing that requirement on those APIs later, but that should be done in a followup imo. * I've ported a few examples to illustrate real-world usage. I think in a followup we should port all examples to the `children!` form whenever possible (and for cases that require things like SpawnIter, use the raw APIs). * Some may ask "why not use the `Relationship` to spawn (ex: `ChildOf::spawn(Foo)`) instead of the `RelationshipTarget` (ex: `Children::spawn(Spawn(Foo))`)?". That _would_ allow us to remove the `Spawn` wrapper. I've explicitly chosen to disallow this pattern. `Bundle::Effect` has the ability to create _significant_ weirdness. Things in `Bundle` position look like components. For example `world.spawn((Foo, ChildOf::spawn(Bar)))` _looks and reads_ like Foo is a child of Bar. `ChildOf` is in Foo's "component position" but it is not a component on Foo. This is a huge problem. Now that `Bundle::Effect` exists, we should be _very_ principled about keeping the "weird and unintuitive behavior" to a minimum. Things that read like components _should be the components they appear to be". ## Remaining Work * The macros are currently trivially implemented using macro_rules and are currently limited to the max tuple length. They will require a proc_macro implementation to work around the tuple length limit. ## Next Steps * Port the remaining examples to use `children!` where possible and raw `Spawn` / `SpawnIter` / `SpawnWith` where the flexibility of the raw API is required. ## Migration Guide Existing spawn patterns will continue to work as expected. Manual Bundle implementations now require a `BundleEffect` associated type. Exisiting bundles would have no bundle effect, so use `()`. Additionally `Bundle::from_components` has been moved to the new `BundleFromComponents` trait. ```rust // Before unsafe impl Bundle for X { unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self { } /* remaining bundle impl here */ } // After unsafe impl Bundle for X { type Effect = (); /* remaining bundle impl here */ } unsafe impl BundleFromComponents for X { unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self { } } ``` --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com> Co-authored-by: Emerson Coskey <emerson@coskey.dev> |
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1b7db895b7
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Harden proc macro path resolution and add integration tests. (#17330)
This pr uses the `extern crate self as` trick to make proc macros behave the same way inside and outside bevy. # Objective - Removes noise introduced by `crate as` in the whole bevy repo. - Fixes #17004. - Hardens proc macro path resolution. ## TODO - [x] `BevyManifest` needs cleanup. - [x] Cleanup remaining `crate as`. - [x] Add proper integration tests to the ci. ## Notes - `cargo-manifest-proc-macros` is written by me and based/inspired by the old `BevyManifest` implementation and [`bkchr/proc-macro-crate`](https://github.com/bkchr/proc-macro-crate). - What do you think about the new integration test machinery I added to the `ci`? More and better integration tests can be added at a later stage. The goal of these integration tests is to simulate an actual separate crate that uses bevy. Ideally they would lightly touch all bevy crates. ## Testing - Needs RA test - Needs testing from other users - Others need to run at least `cargo run -p ci integration-test` and verify that they work. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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3c8fae2390
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Improved Entity Mapping and Cloning (#17687)
Fixes #17535 Bevy's approach to handling "entity mapping" during spawning and cloning needs some work. The addition of [Relations](https://github.com/bevyengine/bevy/pull/17398) both [introduced a new "duplicate entities" bug when spawning scenes in the scene system](#17535) and made the weaknesses of the current mapping system exceedingly clear: 1. Entity mapping requires _a ton_ of boilerplate (implement or derive VisitEntities and VisitEntitesMut, then register / reflect MapEntities). Knowing the incantation is challenging and if you forget to do it in part or in whole, spawning subtly breaks. 2. Entity mapping a spawned component in scenes incurs unnecessary overhead: look up ReflectMapEntities, create a _brand new temporary instance_ of the component using FromReflect, map the entities in that instance, and then apply that on top of the actual component using reflection. We can do much better. Additionally, while our new [Entity cloning system](https://github.com/bevyengine/bevy/pull/16132) is already pretty great, it has some areas we can make better: * It doesn't expose semantic info about the clone (ex: ignore or "clone empty"), meaning we can't key off of that in places where it would be useful, such as scene spawning. Rather than duplicating this info across contexts, I think it makes more sense to add that info to the clone system, especially given that we'd like to use cloning code in some of our spawning scenarios. * EntityCloner is currently built in a way that prioritizes a single entity clone * EntityCloner's recursive cloning is built to be done "inside out" in a parallel context (queue commands that each have a clone of EntityCloner). By making EntityCloner the orchestrator of the clone we can remove internal arcs, improve the clarity of the code, make EntityCloner mutable again, and simplify the builder code. * EntityCloner does not currently take into account entity mapping. This is necessary to do true "bullet proof" cloning, would allow us to unify the per-component scene spawning and cloning UX, and ultimately would allow us to use EntityCloner in place of raw reflection for scenes like `Scene(World)` (which would give us a nice performance boost: fewer archetype moves, less reflection overhead). ## Solution ### Improved Entity Mapping First, components now have first-class "entity visiting and mapping" behavior: ```rust #[derive(Component, Reflect)] #[reflect(Component)] struct Inventory { size: usize, #[entities] items: Vec<Entity>, } ``` Any field with the `#[entities]` annotation will be viewable and mappable when cloning and spawning scenes. Compare that to what was required before! ```rust #[derive(Component, Reflect, VisitEntities, VisitEntitiesMut)] #[reflect(Component, MapEntities)] struct Inventory { #[visit_entities(ignore)] size: usize, items: Vec<Entity>, } ``` Additionally, for relationships `#[entities]` is implied, meaning this "just works" in scenes and cloning: ```rust #[derive(Component, Reflect)] #[relationship(relationship_target = Children)] #[reflect(Component)] struct ChildOf(pub Entity); ``` Note that Component _does not_ implement `VisitEntities` directly. Instead, it has `Component::visit_entities` and `Component::visit_entities_mut` methods. This is for a few reasons: 1. We cannot implement `VisitEntities for C: Component` because that would conflict with our impl of VisitEntities for anything that implements `IntoIterator<Item=Entity>`. Preserving that impl is more important from a UX perspective. 2. We should not implement `Component: VisitEntities` VisitEntities in the Component derive, as that would increase the burden of manual Component trait implementors. 3. Making VisitEntitiesMut directly callable for components would make it easy to invalidate invariants defined by a component author. By putting it in the `Component` impl, we can make it harder to call naturally / unavailable to autocomplete using `fn visit_entities_mut(this: &mut Self, ...)`. `ReflectComponent::apply_or_insert` is now `ReflectComponent::apply_or_insert_mapped`. By moving mapping inside this impl, we remove the need to go through the reflection system to do entity mapping, meaning we no longer need to create a clone of the target component, map the entities in that component, and patch those values on top. This will make spawning mapped entities _much_ faster (The default `Component::visit_entities_mut` impl is an inlined empty function, so it will incur no overhead for unmapped entities). ### The Bug Fix To solve #17535, spawning code now skips entities with the new `ComponentCloneBehavior::Ignore` and `ComponentCloneBehavior::RelationshipTarget` variants (note RelationshipTarget is a temporary "workaround" variant that allows scenes to skip these components. This is a temporary workaround that can be removed as these cases should _really_ be using EntityCloner logic, which should be done in a followup PR. When that is done, `ComponentCloneBehavior::RelationshipTarget` can be merged into the normal `ComponentCloneBehavior::Custom`). ### Improved Cloning * `Option<ComponentCloneHandler>` has been replaced by `ComponentCloneBehavior`, which encodes additional intent and context (ex: `Default`, `Ignore`, `Custom`, `RelationshipTarget` (this last one is temporary)). * Global per-world entity cloning configuration has been removed. This felt overly complicated, increased our API surface, and felt too generic. Each clone context can have different requirements (ex: what a user wants in a specific system, what a scene spawner wants, etc). I'd prefer to see how far context-specific EntityCloners get us first. * EntityCloner's internals have been reworked to remove Arcs and make it mutable. * EntityCloner is now directly stored on EntityClonerBuilder, simplifying the code somewhat * EntityCloner's "bundle scratch" pattern has been moved into the new BundleScratch type, improving its usability and making it usable in other contexts (such as future cross-world cloning code). Currently this is still private, but with some higher level safe APIs it could be used externally for making dynamic bundles * EntityCloner's recursive cloning behavior has been "externalized". It is now responsible for orchestrating recursive clones, meaning it no longer needs to be sharable/clone-able across threads / read-only. * EntityCloner now does entity mapping during clones, like scenes do. This gives behavior parity and also makes it more generically useful. * `RelatonshipTarget::RECURSIVE_SPAWN` is now `RelationshipTarget::LINKED_SPAWN`, and this field is used when cloning relationship targets to determine if cloning should happen recursively. The new `LINKED_SPAWN` term was picked to make it more generically applicable across spawning and cloning scenarios. ## Next Steps * I think we should adapt EntityCloner to support cross world cloning. I think this PR helps set the stage for that by making the internals slightly more generalized. We could have a CrossWorldEntityCloner that reuses a lot of this infrastructure. * Once we support cross world cloning, we should use EntityCloner to spawn `Scene(World)` scenes. This would yield significant performance benefits (no archetype moves, less reflection overhead). --------- Co-authored-by: eugineerd <70062110+eugineerd@users.noreply.github.com> Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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1b2cf7d6cd
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Isolate component registration (#17671)
# Objective Progresses #17569. The end goal here is to synchronize component registration. See the other PR for details for the motivation behind that. For this PR specifically, the objective is to decouple `Components` from `Storages`. What components are registered etc should have nothing to do with what Storages looks like. Storages should only care about what entity archetypes have been spawned. ## Solution Previously, this was used to create sparse sets for relevant components when those components were registered. Now, we do that when the component is inserted/spawned. This PR proposes doing that in `BundleInfo::new`, but there may be a better place. ## Testing In theory, this shouldn't have changed any functionality, so no new tests were created. I'm not aware of any examples that make heavy use of sparse set components either. ## Migration Guide - Remove storages from functions where it is no longer needed. - Note that SparseSets are no longer present for all registered sparse set components, only those that have been spawned. --------- Co-authored-by: SpecificProtagonist <vincentjunge@posteo.net> Co-authored-by: Chris Russell <8494645+chescock@users.noreply.github.com> |
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62285a47ba
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Add simple Disabled marker (#17514)
# Objective We have default query filters now, but there is no first-party marker for entity disabling yet Fixes #17458 ## Solution Add the marker, cool recursive features and/or potential hook changes should be follow up work ## Testing Added a unit test to check that the new marker is enabled by default |
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361397fcac
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Add a test for direct recursion in required components. (#17626)
I realized there wasn't a test for this yet and figured it would be trivial to add. Why not? Unless there was a test for this, and I just missed it? I appreciate the unique error message it gives and wanted to make sure it doesn't get broken at some point. Or worse, endlessly recurse. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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9bc0ae33c3
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Move hashbrown and foldhash out of bevy_utils (#17460)
# Objective - Contributes to #16877 ## Solution - Moved `hashbrown`, `foldhash`, and related types out of `bevy_utils` and into `bevy_platform_support` - Refactored the above to match the layout of these types in `std`. - Updated crates as required. ## Testing - CI --- ## Migration Guide - The following items were moved out of `bevy_utils` and into `bevy_platform_support::hash`: - `FixedState` - `DefaultHasher` - `RandomState` - `FixedHasher` - `Hashed` - `PassHash` - `PassHasher` - `NoOpHash` - The following items were moved out of `bevy_utils` and into `bevy_platform_support::collections`: - `HashMap` - `HashSet` - `bevy_utils::hashbrown` has been removed. Instead, import from `bevy_platform_support::collections` _or_ take a dependency on `hashbrown` directly. - `bevy_utils::Entry` has been removed. Instead, import from `bevy_platform_support::collections::hash_map` or `bevy_platform_support::collections::hash_set` as appropriate. - All of the above equally apply to `bevy::utils` and `bevy::platform_support`. ## Notes - I left `PreHashMap`, `PreHashMapExt`, and `TypeIdMap` in `bevy_utils` as they might be candidates for micro-crating. They can always be moved into `bevy_platform_support` at a later date if desired. |
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41e79ae826
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Refactored ComponentHook Parameters into HookContext (#17503)
# Objective - Make the function signature for `ComponentHook` less verbose ## Solution - Refactored `Entity`, `ComponentId`, and `Option<&Location>` into a new `HookContext` struct. ## Testing - CI --- ## Migration Guide Update the function signatures for your component hooks to only take 2 arguments, `world` and `context`. Note that because `HookContext` is plain data with all members public, you can use de-structuring to simplify migration. ```rust // Before fn my_hook( mut world: DeferredWorld, entity: Entity, component_id: ComponentId, ) { ... } // After fn my_hook( mut world: DeferredWorld, HookContext { entity, component_id, caller }: HookContext, ) { ... } ``` Likewise, if you were discarding certain parameters, you can use `..` in the de-structuring: ```rust // Before fn my_hook( mut world: DeferredWorld, entity: Entity, _: ComponentId, ) { ... } // After fn my_hook( mut world: DeferredWorld, HookContext { entity, .. }: HookContext, ) { ... } ``` |
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f32a6fb205
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Track callsite for observers & hooks (#15607)
# Objective Fixes #14708 Also fixes some commands not updating tracked location. ## Solution `ObserverTrigger` has a new `caller` field with the `track_change_detection` feature; hooks take an additional caller parameter (which is `Some(…)` or `None` depending on the feature). ## Testing See the new tests in `src/observer/mod.rs` --- ## Showcase Observers now know from where they were triggered (if `track_change_detection` is enabled): ```rust world.observe(move |trigger: Trigger<OnAdd, Foo>| { println!("Added Foo from {}", trigger.caller()); }); ``` ## Migration - hooks now take an additional `Option<&'static Location>` argument --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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fe24652cc0
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Change World::try_despawn and World::try_insert_batch to return Result (#17376)
## Objective Most `try` methods on `World` return a `Result`, but `try_despawn` and `try_insert_batch` don't. Since Bevy's error handling is advancing, these should be brought in line. ## Solution - Added `TryDespawnError` and `TryInsertBatchError`. - `try_despawn`, `try_insert_batch`, and `try_insert_batch_if_new` now return their respective errors. - Fixed slightly incorrect behavior in `try_insert_batch_with_caller`. - The method was always meant to continue with the rest of the batch if an entity was missing, but that only worked after the first entity; if the first entity was missing, the method would exit early. This has been resolved. ## Migration Guide - `World::try_despawn` now returns a `Result` rather than a `bool`. - `World::try_insert_batch` and `World::try_insert_batch_if_new` now return a `Result` where they previously returned nothing. |
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44ad3bf62b
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Move Resource trait to its own file (#17469)
# Objective `bevy_ecs`'s `system` module is something of a grab bag, and *very* large. This is particularly true for the `system_param` module, which is more than 2k lines long! While it could be defensible to put `Res` and `ResMut` there (lol no they're in change_detection.rs, obviously), it doesn't make any sense to put the `Resource` trait there. This is confusing to navigate (and painful to work on and review). ## Solution - Create a root level `bevy_ecs/resource.rs` module to mirror `bevy_ecs/component.rs` - move the `Resource` trait to that module - move the `Resource` derive macro to that module as well (Rust really likes when you pun on the names of the derive macro and trait and put them in the same path) - fix all of the imports ## Notes to reviewers - We could probably move more stuff into here, but I wanted to keep this PR as small as possible given the absurd level of import changes. - This PR is ground work for my upcoming attempts to store resource data on components (resources-as-entities). Splitting this code out will make the work and review a bit easier, and is the sort of overdue refactor that's good to do as part of more meaningful work. ## Testing cargo build works! ## Migration Guide `bevy_ecs::system::Resource` has been moved to `bevy_ecs::resource::Resource`. |
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ba5e71f53d
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Parent -> ChildOf (#17427)
Fixes #17412 ## Objective `Parent` uses the "has a X" naming convention. There is increasing sentiment that we should use the "is a X" naming convention for relationships (following #17398). This leaves `Children` as-is because there is prevailing sentiment that `Children` is clearer than `ParentOf` in many cases (especially when treating it like a collection). This renames `Parent` to `ChildOf`. This is just the implementation PR. To discuss the path forward, do so in #17412. ## Migration Guide - The `Parent` component has been renamed to `ChildOf`. |
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de5486725d
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Add DefaultQueryFilters (#13120)
# Objective Some usecases in the ecosystems are blocked by the inability to stop bevy internals and third party plugins from touching their entities. However the specifics of a general purpose entity disabling system are controversial and further complicated by hierarchies. We can partially unblock these usecases with an opt-in approach: default query filters. ## Solution - Introduce DefaultQueryFilters, these filters are automatically applied to queries that don't otherwise mention the filtered component. - End users and third party plugins can register default filters and are responsible for handling entities they have hidden this way. - Extra features can be left for after user feedback - The default value could later include official ways to hide entities --- ## Changelog - Add DefaultQueryFilters |
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21f1e3045c
|
Relationships (non-fragmenting, one-to-many) (#17398)
This adds support for one-to-many non-fragmenting relationships (with planned paths for fragmenting and non-fragmenting many-to-many relationships). "Non-fragmenting" means that entities with the same relationship type, but different relationship targets, are not forced into separate tables (which would cause "table fragmentation"). Functionally, this fills a similar niche as the current Parent/Children system. The biggest differences are: 1. Relationships have simpler internals and significantly improved performance and UX. Commands and specialized APIs are no longer necessary to keep everything in sync. Just spawn entities with the relationship components you want and everything "just works". 2. Relationships are generalized. Bevy can provide additional built in relationships, and users can define their own. **REQUEST TO REVIEWERS**: _please don't leave top level comments and instead comment on specific lines of code. That way we can take advantage of threaded discussions. Also dont leave comments simply pointing out CI failures as I can read those just fine._ ## Built on top of what we have Relationships are implemented on top of the Bevy ECS features we already have: components, immutability, and hooks. This makes them immediately compatible with all of our existing (and future) APIs for querying, spawning, removing, scenes, reflection, etc. The fewer specialized APIs we need to build, maintain, and teach, the better. ## Why focus on one-to-many non-fragmenting first? 1. This allows us to improve Parent/Children relationships immediately, in a way that is reasonably uncontroversial. Switching our hierarchy to fragmenting relationships would have significant performance implications. ~~Flecs is heavily considering a switch to non-fragmenting relations after careful considerations of the performance tradeoffs.~~ _(Correction from @SanderMertens: Flecs is implementing non-fragmenting storage specialized for asset hierarchies, where asset hierarchies are many instances of small trees that have a well defined structure)_ 2. Adding generalized one-to-many relationships is currently a priority for the [Next Generation Scene / UI effort](https://github.com/bevyengine/bevy/discussions/14437). Specifically, we're interested in building reactions and observers on top. ## The changes This PR does the following: 1. Adds a generic one-to-many Relationship system 3. Ports the existing Parent/Children system to Relationships, which now lives in `bevy_ecs::hierarchy`. The old `bevy_hierarchy` crate has been removed. 4. Adds on_despawn component hooks 5. Relationships can opt-in to "despawn descendants" behavior, meaning that the entire relationship hierarchy is despawned when `entity.despawn()` is called. The built in Parent/Children hierarchies enable this behavior, and `entity.despawn_recursive()` has been removed. 6. `world.spawn` now applies commands after spawning. This ensures that relationship bookkeeping happens immediately and removes the need to manually flush. This is in line with the equivalent behaviors recently added to the other APIs (ex: insert). 7. Removes the ValidParentCheckPlugin (system-driven / poll based) in favor of a `validate_parent_has_component` hook. ## Using Relationships The `Relationship` trait looks like this: ```rust pub trait Relationship: Component + Sized { type RelationshipSources: RelationshipSources<Relationship = Self>; fn get(&self) -> Entity; fn from(entity: Entity) -> Self; } ``` A relationship is a component that: 1. Is a simple wrapper over a "target" Entity. 2. Has a corresponding `RelationshipSources` component, which is a simple wrapper over a collection of entities. Every "target entity" targeted by a "source entity" with a `Relationship` has a `RelationshipSources` component, which contains every "source entity" that targets it. For example, the `Parent` component (as it currently exists in Bevy) is the `Relationship` component and the entity containing the Parent is the "source entity". The entity _inside_ the `Parent(Entity)` component is the "target entity". And that target entity has a `Children` component (which implements `RelationshipSources`). In practice, the Parent/Children relationship looks like this: ```rust #[derive(Relationship)] #[relationship(relationship_sources = Children)] pub struct Parent(pub Entity); #[derive(RelationshipSources)] #[relationship_sources(relationship = Parent)] pub struct Children(Vec<Entity>); ``` The Relationship and RelationshipSources derives automatically implement Component with the relevant configuration (namely, the hooks necessary to keep everything in sync). The most direct way to add relationships is to spawn entities with relationship components: ```rust let a = world.spawn_empty().id(); let b = world.spawn(Parent(a)).id(); assert_eq!(world.entity(a).get::<Children>().unwrap(), &[b]); ``` There are also convenience APIs for spawning more than one entity with the same relationship: ```rust world.spawn_empty().with_related::<Children>(|s| { s.spawn_empty(); s.spawn_empty(); }) ``` The existing `with_children` API is now a simpler wrapper over `with_related`. This makes this change largely non-breaking for existing spawn patterns. ```rust world.spawn_empty().with_children(|s| { s.spawn_empty(); s.spawn_empty(); }) ``` There are also other relationship APIs, such as `add_related` and `despawn_related`. ## Automatic recursive despawn via the new on_despawn hook `RelationshipSources` can opt-in to "despawn descendants" behavior, which will despawn all related entities in the relationship hierarchy: ```rust #[derive(RelationshipSources)] #[relationship_sources(relationship = Parent, despawn_descendants)] pub struct Children(Vec<Entity>); ``` This means that `entity.despawn_recursive()` is no longer required. Instead, just use `entity.despawn()` and the relevant related entities will also be despawned. To despawn an entity _without_ despawning its parent/child descendants, you should remove the `Children` component first, which will also remove the related `Parent` components: ```rust entity .remove::<Children>() .despawn() ``` This builds on the on_despawn hook introduced in this PR, which is fired when an entity is despawned (before other hooks). ## Relationships are the source of truth `Relationship` is the _single_ source of truth component. `RelationshipSources` is merely a reflection of what all the `Relationship` components say. By embracing this, we are able to significantly improve the performance of the system as a whole. We can rely on component lifecycles to protect us against duplicates, rather than needing to scan at runtime to ensure entities don't already exist (which results in quadratic runtime). A single source of truth gives us constant-time inserts. This does mean that we cannot directly spawn populated `Children` components (or directly add or remove entities from those components). I personally think this is a worthwhile tradeoff, both because it makes the performance much better _and_ because it means theres exactly one way to do things (which is a philosophy we try to employ for Bevy APIs). As an aside: treating both sides of the relationship as "equivalent source of truth relations" does enable building simple and flexible many-to-many relationships. But this introduces an _inherent_ need to scan (or hash) to protect against duplicates. [`evergreen_relations`](https://github.com/EvergreenNest/evergreen_relations) has a very nice implementation of the "symmetrical many-to-many" approach. Unfortunately I think the performance issues inherent to that approach make it a poor choice for Bevy's default relationship system. ## Followup Work * Discuss renaming `Parent` to `ChildOf`. I refrained from doing that in this PR to keep the diff reasonable, but I'm personally biased toward this change (and using that naming pattern generally for relationships). * [Improved spawning ergonomics](https://github.com/bevyengine/bevy/discussions/16920) * Consider adding relationship observers/triggers for "relationship targets" whenever a source is added or removed. This would replace the current "hierarchy events" system, which is unused upstream but may have existing users downstream. I think triggers are the better fit for this than a buffered event queue, and would prefer not to add that back. * Fragmenting relations: My current idea hinges on the introduction of "value components" (aka: components whose type _and_ value determines their ComponentId, via something like Hashing / PartialEq). By labeling a Relationship component such as `ChildOf(Entity)` as a "value component", `ChildOf(e1)` and `ChildOf(e2)` would be considered "different components". This makes the transition between fragmenting and non-fragmenting a single flag, and everything else continues to work as expected. * Many-to-many support * Non-fragmenting: We can expand Relationship to be a list of entities instead of a single entity. I have largely already written the code for this. * Fragmenting: With the "value component" impl mentioned above, we get many-to-many support "for free", as it would allow inserting multiple copies of a Relationship component with different target entities. Fixes #3742 (If this PR is merged, I think we should open more targeted followup issues for the work above, with a fresh tracking issue free of the large amount of less-directed historical context) Fixes #17301 Fixes #12235 Fixes #15299 Fixes #15308 ## Migration Guide * Replace `ChildBuilder` with `ChildSpawnerCommands`. * Replace calls to `.set_parent(parent_id)` with `.insert(Parent(parent_id))`. * Replace calls to `.replace_children()` with `.remove::<Children>()` followed by `.add_children()`. Note that you'll need to manually despawn any children that are not carried over. * Replace calls to `.despawn_recursive()` with `.despawn()`. * Replace calls to `.despawn_descendants()` with `.despawn_related::<Children>()`. * If you have any calls to `.despawn()` which depend on the children being preserved, you'll need to remove the `Children` component first. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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26bb0b40d2
|
Move #![warn(clippy::allow_attributes, clippy::allow_attributes_without_reason)] to the workspace Cargo.toml (#17374)
# Objective Fixes https://github.com/bevyengine/bevy/issues/17111 ## Solution Move `#![warn(clippy::allow_attributes, clippy::allow_attributes_without_reason)]` to the workspace `Cargo.toml` ## Testing Lots of CI testing, and local testing too. --------- Co-authored-by: Benjamin Brienen <benjamin.brienen@outlook.com> |
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17c46f4add
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bevy_ecs: Apply #![warn(clippy::allow_attributes, clippy::allow_attributes_without_reason)] (#17335)
# Objective - https://github.com/bevyengine/bevy/issues/17111 ## Solution Set the `clippy::allow_attributes` and `clippy::allow_attributes_without_reason` lints to `warn`, and bring `bevy_ecs` in line with the new restrictions. ## Testing This PR is a WIP; testing will happen after it's finished. |
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ee4414159b
|
Add Result handling to Commands and EntityCommands (#17043)
## Objective Fixes #2004 Fixes #3845 Fixes #7118 Fixes #10166 ## Solution - The crux of this PR is the new `Command::with_error_handling` method. This wraps the relevant command in another command that, when applied, will apply the original command and handle any resulting errors. - To enable this, `Command::apply` and `EntityCommand::apply` now return `Result`. - `Command::with_error_handling` takes as a parameter an error handler of the form `fn(&mut World, CommandError)`, which it passes the error to. - `CommandError` is an enum that can be either `NoSuchEntity(Entity)` or `CommandFailed(Box<dyn Error>)`. ### Closures - Closure commands can now optionally return `Result`, which will be passed to `with_error_handling`. ### Commands - Fallible commands can be queued with `Commands::queue_fallible` and `Commands::queue_fallible_with`, which call `with_error_handling` before queuing them (using `Commands::queue` will queue them without error handling). - `Commands::queue_fallible_with` takes an `error_handler` parameter, which will be used by `with_error_handling` instead of a command's default. - The `command` submodule provides unqueued forms of built-in fallible commands so that you can use them with `queue_fallible_with`. - There is also an `error_handler` submodule that provides simple error handlers for convenience. ### Entity Commands - `EntityCommand` now automatically checks if the entity exists before executing the command, and returns `NoSuchEntity` if it doesn't. - Since all entity commands might need to return an error, they are always queued with error handling. - `EntityCommands::queue_with` takes an `error_handler` parameter, which will be used by `with_error_handling` instead of a command's default. - The `entity_command` submodule provides unqueued forms of built-in entity commands so that you can use them with `queue_with`. ### Defaults - In the future, commands should all fail according to the global error handling setting. That doesn't exist yet though. - For this PR, commands all fail the way they do on `main`. - Both now and in the future, the defaults can be overridden by `Commands::override_error_handler` (or equivalent methods on `EntityCommands` and `EntityEntryCommands`). - `override_error_handler` takes an error handler (`fn(&mut World, CommandError)`) and passes it to every subsequent command queued with `Commands::queue_fallible` or `EntityCommands::queue`. - The `_with` variants of the queue methods will still provide an error handler directly to the command. - An override can be reset with `reset_error_handler`. ## Future Work - After a universal error handling mode is added, we can change all commands to fail that way by default. - Once we have all commands failing the same way (which would require either the full removal of `try` variants or just making them useless while they're deprecated), `queue_fallible_with_default` could be removed, since its only purpose is to enable commands having different defaults. |
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0403948aa2
|
Remove Implicit std Prelude from no_std Crates (#17086)
# Background In `no_std` compatible crates, there is often an `std` feature which will allow access to the standard library. Currently, with the `std` feature _enabled_, the [`std::prelude`](https://doc.rust-lang.org/std/prelude/index.html) is implicitly imported in all modules. With the feature _disabled_, instead the [`core::prelude`](https://doc.rust-lang.org/core/prelude/index.html) is implicitly imported. This creates a subtle and pervasive issue where `alloc` items _may_ be implicitly included (if `std` is enabled), or must be explicitly included (if `std` is not enabled). # Objective - Make the implicit imports for `no_std` crates consistent regardless of what features are/not enabled. ## Solution - Replace the `cfg_attr` "double negative" `no_std` attribute with conditional compilation to _include_ `std` as an external crate. ```rust // Before #![cfg_attr(not(feature = "std"), no_std)] // After #![no_std] #[cfg(feature = "std")] extern crate std; ``` - Fix imports that are currently broken but are only now visible with the above fix. ## Testing - CI ## Notes I had previously used the "double negative" version of `no_std` based on general consensus that it was "cleaner" within the Rust embedded community. However, this implicit prelude issue likely was considered when forming this consensus. I believe the reason why is the items most affected by this issue are provided by the `alloc` crate, which is rarely used within embedded but extensively used within Bevy. |
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5b899dcc3a
|
impl EntityBorrow for more types (#16917)
# Objective Some types like `RenderEntity` and `MainEntity` are just wrappers around `Entity`, so they should be able to implement `EntityBorrow`/`TrustedEntityBorrow`. This allows using them with `EntitySet` functionality. The `EntityRef` family are more than direct wrappers around `Entity`, but can still benefit from being unique in a collection. ## Solution Implement `EntityBorrow` and `TrustedEntityBorrow` for simple `Entity` newtypes and `EntityRef` types. These impls are an explicit decision to have the `EntityRef` types compare like just `Entity`. `EntityWorldMut` is omitted from this impl, because it explicitly contains a `&mut World` as well, and we do not ever use more than one at a time. Add `EntityBorrow` to the `bevy_ecs` prelude. ## Migration Guide `NormalizedWindowRef::entity` has been replaced with an `EntityBorrow::entity` impl. |
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d4b07a5114
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Move Name out of bevy_core (#16894)
# Objective - Contributes to #16892 ## Solution - Moved `Name` and `NameOrEntity` into `bevy_ecs::name`, and added them to the prelude. ## Testing - CI ## Migration Guide If you were importing `Name` or `NameOrEntity` from `bevy_core`, instead import from `bevy_ecs::name`. --------- Co-authored-by: Christian Hughes <9044780+ItsDoot@users.noreply.github.com> |
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1f2d0e6308
|
Add no_std support to bevy_ecs (#16758)
# Objective - Contributes to #15460 ## Solution - Added the following features: - `std` (default) - `async_executor` (default) - `edge_executor` - `critical-section` - `portable-atomic` - Gated `tracing` in `bevy_utils` to allow compilation on certain platforms - Switched from `tracing` to `log` for simple message logging within `bevy_ecs`. Note that `tracing` supports capturing from `log` so this should be an uncontroversial change. - Fixed imports and added feature gates as required - Made `bevy_tasks` optional within `bevy_ecs`. Turns out it's only needed for parallel operations which are already gated behind `multi_threaded` anyway. ## Testing - Added to `compile-check-no-std` CI command - `cargo check -p bevy_ecs --no-default-features --features edge_executor,critical-section,portable-atomic --target thumbv6m-none-eabi` - `cargo check -p bevy_ecs --no-default-features --features edge_executor,critical-section` - `cargo check -p bevy_ecs --no-default-features` ## Draft Release Notes Bevy's core ECS now supports `no_std` platforms. In prior versions of Bevy, it was not possible to work with embedded or niche platforms due to our reliance on the standard library, `std`. This has blocked a number of novel use-cases for Bevy, such as an embedded database for IoT devices, or for creating games on retro consoles. With this release, `bevy_ecs` no longer requires `std`. To use Bevy on a `no_std` platform, you must disable default features and enable the new `edge_executor` and `critical-section` features. You may also need to enable `portable-atomic` and `critical-section` if your platform does not natively support all atomic types and operations used by Bevy. ```toml [dependencies] bevy_ecs = { version = "0.16", default-features = false, features = [ # Required for platforms with incomplete atomics (e.g., Raspberry Pi Pico) "portable-atomic", "critical-section", # Optional "bevy_reflect", "serialize", "bevy_debug_stepping", "edge_executor" ] } ``` Currently, this has been tested on bare-metal x86 and the Raspberry Pi Pico. If you have trouble using `bevy_ecs` on a particular platform, please reach out either through a GitHub issue or in the `no_std` working group on the Bevy Discord server. Keep an eye out for future `no_std` updates as we continue to improve the parity between `std` and `no_std`. We look forward to seeing what kinds of applications are now possible with Bevy! ## Notes - Creating PR in draft to ensure CI is passing before requesting reviews. - This implementation has no support for multithreading in `no_std`, especially due to `NonSend` being unsound if allowed in multithreading. The reason is we cannot check the `ThreadId` in `no_std`, so we have no mechanism to at-runtime determine if access is sound. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Vic <59878206+Victoronz@users.noreply.github.com> |
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cc0f6a8db4
|
Remove deprecated ECS items (#16853)
# Objective - Cleanup deprecated code ## Solution - Removed `#[deprecated]` items which were marked as such in 0.15 or prior versions. ## Migration Guide - The following deprecated items were removed: `Events::get_reader`, `Events::get_reader_current`, `ManualEventReader`, `Condition::and_then`, `Condition::or_else`, `World::,many_entities`, `World::many_entities_mut`, `World::get_many_entities`, `World::get_many_entities_dynamic`, `World::get_many_entities_mut`, `World::get_many_entities_dynamic_mut`, `World::get_many_entities_from_set_mut` |
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f2719f5470
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Rust 1.83, allow -> expect (missing_docs) (#16561)
# Objective We were waiting for 1.83 to address most of these, due to a bug with `missing_docs` and `expect`. Relates to, but does not entirely complete, #15059. ## Solution - Upgrade to 1.83 - Switch `allow(missing_docs)` to `expect(missing_docs)` - Remove a few now-unused `allow`s along the way, or convert to `expect` |
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5f1e114209
|
Descriptive error message for circular required components recursion (#16648)
# Objective Fixes #16645 ## Solution Keep track of components in callstack when registering required components. ## Testing Added a test checking that the error fires. --- ## Showcase ```rust #[derive(Component, Default)] #[require(B)] struct A; #[derive(Component, Default)] #[require(A)] struct B; World::new().spawn(A); ``` ``` thread 'main' panicked at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/component.rs:415:13: Recursive required components detected: A → B → A ``` --------- Co-authored-by: Chris Russell <8494645+chescock@users.noreply.github.com> |
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711246aa34
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Update hashbrown to 0.15 (#15801)
Updating dependencies; adopted version of #15696. (Supercedes #15696.) Long answer: hashbrown is no longer using ahash by default, meaning that we can't use the default-hasher methods with ahasher. So, we have to use the longer-winded versions instead. This takes the opportunity to also switch our default hasher as well, but without actually enabling the default-hasher feature for hashbrown, meaning that we'll be able to change our hasher more easily at the cost of all of these method calls being obnoxious forever. One large change from 0.15 is that `insert_unique_unchecked` is now `unsafe`, and for cases where unsafe code was denied at the crate level, I replaced it with `insert`. ## Migration Guide `bevy_utils` has updated its version of `hashbrown` to 0.15 and now defaults to `foldhash` instead of `ahash`. This means that if you've hard-coded your hasher to `bevy_utils::AHasher` or separately used the `ahash` crate in your code, you may need to switch to `foldhash` to ensure that everything works like it does in Bevy. |
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4aed2ca74c
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Add World::try_resource_scope (#16707)
# Objective Fixes #16706 ## Solution - Added new method: `try_resource_scope` which returns `None` if the requested resource doesn't exist. - Changed the `resource_scope` test to use `try_resource_scope` as well to test for the `None` case. --- ## Showcase ```rust world.try_resource_scope::<MyResource, _>(|world, mut my_resource| { // do something with the resource if it exists }); ``` |
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a6adced9ed
|
Deny derive_more error feature and replace it with thiserror (#16684)
# Objective - Remove `derive_more`'s error derivation and replace it with `thiserror` ## Solution - Added `derive_more`'s `error` feature to `deny.toml` to prevent it sneaking back in. - Reverted to `thiserror` error derivation ## Notes Merge conflicts were too numerous to revert the individual changes, so this reversion was done manually. Please scrutinise carefully during review. |
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0070514f54
|
Fallible systems (#16589)
# Objective Error handling in bevy is hard. See for reference https://github.com/bevyengine/bevy/issues/11562, https://github.com/bevyengine/bevy/issues/10874 and https://github.com/bevyengine/bevy/issues/12660. The goal of this PR is to make it better, by allowing users to optionally return `Result` from systems as outlined by Cart in <https://github.com/bevyengine/bevy/issues/14275#issuecomment-2223708314>. ## Solution This PR introduces a new `ScheuleSystem` type to represent systems that can be added to schedules. Instances of this type contain either an infallible `BoxedSystem<(), ()>` or a fallible `BoxedSystem<(), Result>`. `ScheuleSystem` implements `System<In = (), Out = Result>` and replaces all uses of `BoxedSystem` in schedules. The async executor now receives a result after executing a system, which for infallible systems is always `Ok(())`. Currently it ignores this result, but more useful error handling could also be implemented. Aliases for `Error` and `Result` have been added to the `bevy_ecs` prelude, as well as const `OK` which new users may find more friendly than `Ok(())`. ## Testing - Currently there are not actual semantics changes that really require new tests, but I added a basic one just to make sure we don't break stuff in the future. - The behavior of existing systems is totally unchanged, including logging. - All of the existing systems tests pass, and I have not noticed anything strange while playing with the examples ## Showcase The following minimal example prints "hello world" once, then completes. ```rust use bevy::prelude::*; fn main() { App::new().add_systems(Update, hello_world_system).run(); } fn hello_world_system() -> Result { println!("hello world"); Err("string")?; println!("goodbye world"); OK } ``` ## Migration Guide This change should be pretty much non-breaking, except for users who have implemented their own custom executors. Those users should use `ScheduleSystem` in place of `BoxedSystem<(), ()>` and import the `System` trait where needed. They can choose to do whatever they wish with the result. ## Current Work + [x] Fix tests & doc comments + [x] Write more tests + [x] Add examples + [X] Draft release notes ## Draft Release Notes As of this release, systems can now return results. First a bit of background: Bevy has hisotrically expected systems to return the empty type `()`. While this makes sense in the context of the ecs, it's at odds with how error handling is typically done in rust: returning `Result::Error` to indicate failure, and using the short-circuiting `?` operator to propagate that error up the call stack to where it can be properly handled. Users of functional languages will tell you this is called "monadic error handling". Not being able to return `Results` from systems left bevy users with a quandry. They could add custom error handling logic to every system, or manually pipe every system into an error handler, or perhaps sidestep the issue with some combination of fallible assignents, logging, macros, and early returns. Often, users would just litter their systems with unwraps and possible panics. While any one of these approaches might be fine for a particular user, each of them has their own drawbacks, and none makes good use of the language. Serious issues could also arrise when two different crates used by the same project made different choices about error handling. Now, by returning results, systems can defer error handling to the application itself. It looks like this: ```rust // Previous, handling internally app.add_systems(my_system) fn my_system(window: Query<&Window>) { let Ok(window) = query.get_single() else { return; }; // ... do something to the window here } // Previous, handling externally app.add_systems(my_system.pipe(my_error_handler)) fn my_system(window: Query<&Window>) -> Result<(), impl Error> { let window = query.get_single()?; // ... do something to the window here Ok(()) } // Previous, panicking app.add_systems(my_system) fn my_system(window: Query<&Window>) { let window = query.single(); // ... do something to the window here } // Now app.add_systems(my_system) fn my_system(window: Query<&Window>) -> Result { let window = query.get_single()?; // ... do something to the window here Ok(()) } ``` There are currently some limitations. Systems must either return `()` or `Result<(), Box<dyn Error + Send + Sync + 'static>>`, with no in-between. Results are also ignored by default, and though implementing a custom handler is possible, it involves writing your own custom ecs executor (which is *not* recomended). Systems should return errors when they cannot perform their normal behavior. In turn, errors returned to the executor while running the schedule will (eventually) be treated as unexpected. Users and library authors should prefer to return errors for anything that disrupts the normal expected behavior of a system, and should only handle expected cases internally. We have big plans for improving error handling further: + Allowing users to change the error handling logic of the default executors. + Adding source tracking and optional backtraces to errors. + Possibly adding tracing-levels (Error/Warn/Info/Debug/Trace) to errors. + Generally making the default error logging more helpful and inteligent. + Adding monadic system combininators for fallible systems. + Possibly removing all panicking variants from our api. --------- Co-authored-by: Zachary Harrold <zac@harrold.com.au> |
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f87b9fe20c
|
Turn apply_deferred into a ZST System (#16642)
# Objective - Required by #16622 due to differing implementations of `System` by `FunctionSystem` and `ExclusiveFunctionSystem`. - Optimize the memory usage of instances of `apply_deferred` in system schedules. ## Solution By changing `apply_deferred` from being an ordinary system that ends up as an `ExclusiveFunctionSystem`, and instead into a ZST struct that implements `System` manually, we save ~320 bytes per instance of `apply_deferred` in any schedule. ## Testing - All current tests pass. --- ## Migration Guide - If you were previously calling the special `apply_deferred` system via `apply_deferred(world)`, don't. |
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d92fc1e456
|
Move required components doc to type doc (#16575)
# Objective Make documentation of a component's required components more visible by moving it to the type's docs ## Solution Change `#[require]` from a derive macro helper to an attribute macro. Disadvantages: - this silences any unused code warnings on the component, as it is used by the macro! - need to import `require` if not using the ecs prelude (I have not included this in the migration guilde as Rust tooling already suggests the fix) --- ## Showcase  --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com> |
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2e267bba5a
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Entity cloning (#16132)
## Objective Fixes #1515 This PR implements a flexible entity cloning system. The primary use case for it is to clone dynamically-generated entities. Example: ```rs #[derive(Component, Clone)] pub struct Projectile; #[derive(Component, Clone)] pub struct Damage { value: f32, } fn player_input( mut commands: Commands, projectiles: Query<Entity, With<Projectile>>, input: Res<ButtonInput<KeyCode>>, ) { // Fire a projectile if input.just_pressed(KeyCode::KeyF) { commands.spawn((Projectile, Damage { value: 10.0 })); } // Triplicate all active projectiles if input.just_pressed(KeyCode::KeyT) { for projectile in projectiles.iter() { // To triplicate a projectile we need to create 2 more clones for _ in 0..2{ commands.clone_entity(projectile) } } } } ``` ## Solution ### Commands Add a `clone_entity` command to create a clone of an entity with all components that can be cloned. Components that can't be cloned will be ignored. ```rs commands.clone_entity(entity) ``` If there is a need to configure the cloning process (like set to clone recursively), there is a second command: ```rs commands.clone_entity_with(entity, |builder| { builder.recursive(true) }); ``` Both of these commands return `EntityCommands` of the cloned entity, so the copy can be modified afterwards. ### Builder All these commands use `EntityCloneBuilder` internally. If there is a need to clone an entity using `World` instead, it is also possible: ```rs let entity = world.spawn(Component).id(); let entity_clone = world.spawn_empty().id(); EntityCloneBuilder::new(&mut world).clone_entity(entity, entity_clone); ``` Builder has methods to `allow` or `deny` certain components during cloning if required and can be extended by implementing traits on it. This PR includes two `EntityCloneBuilder` extensions: `CloneEntityWithObserversExt` to configure adding cloned entity to observers of the original entity, and `CloneEntityRecursiveExt` to configure cloning an entity recursively. ### Clone implementations By default, all components that implement either `Clone` or `Reflect` will be cloned (with `Clone`-based implementation preferred in case component implements both). This can be overriden on a per-component basis: ```rs impl Component for SomeComponent { const STORAGE_TYPE: StorageType = StorageType::Table; fn get_component_clone_handler() -> ComponentCloneHandler { // Don't clone this component ComponentCloneHandler::Ignore } } ``` ### `ComponentCloneHandlers` Clone implementation specified in `get_component_clone_handler` will get registered in `ComponentCloneHandlers` (stored in `bevy_ecs::component::Components`) at component registration time. The clone handler implementation provided by a component can be overriden after registration like so: ```rs let component_id = world.components().component_id::<Component>().unwrap() world.get_component_clone_handlers_mut() .set_component_handler(component_id, ComponentCloneHandler::Custom(component_clone_custom)) ``` The default clone handler for all components that do not explicitly define one (or don't derive `Component`) is `component_clone_via_reflect` if `bevy_reflect` feature is enabled, and `component_clone_ignore` (noop) otherwise. Default handler can be overriden using `ComponentCloneHandlers::set_default_handler` ### Handlers Component clone handlers can be used to modify component cloning behavior. The general signature for a handler that can be used in `ComponentCloneHandler::Custom` is as follows: ```rs pub fn component_clone_custom( world: &mut DeferredWorld, entity_cloner: &EntityCloner, ) { // implementation } ``` The `EntityCloner` implementation (used internally by `EntityCloneBuilder`) assumes that after calling this custom handler, the `target` entity has the desired version of the component from the `source` entity. ### Builder handler overrides Besides component-defined and world-overriden handlers, `EntityCloneBuilder` also has a way to override handlers locally. It is mainly used to allow configuration methods like `recursive` and `add_observers`. ```rs // From observer clone handler implementation impl CloneEntityWithObserversExt for EntityCloneBuilder<'_> { fn add_observers(&mut self, add_observers: bool) -> &mut Self { if add_observers { self.override_component_clone_handler::<ObservedBy>(ComponentCloneHandler::Custom( component_clone_observed_by, )) } else { self.remove_component_clone_handler_override::<ObservedBy>() } } } ``` ## Testing Includes some basic functionality tests and doctests. Performance-wise this feature is the same as calling `clone` followed by `insert` for every entity component. There is also some inherent overhead due to every component clone handler having to access component data through `World`, but this can be reduced without breaking current public API in a later PR. |
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6741e01dfa
|
Fix adding a subtree of required components to an existing tree replacing shallower required component constructors (#16441)
# Objective - Fixes #16406 even more. The previous implementation did not take into account the depth of the requiree when setting the depth relative to the required_by component. ## Solution - Add the depth of the requiree! ## Testing - Added a test. --------- Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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4a6b686832
|
Fix runtime required components not registering correctly (#16436)
# Objective - Fixes #16406 - Fixes an issue where registering a "deeper" required component, then a "shallower" required component, would result in the wrong required constructor being used for the root component. ## Solution - Make `register_required_components` add any "parent" of a component as `required_by` to the new "child". - Assign the depth of the `requiree` plus 1 as the depth of a new runtime required component. ## Testing - Added two new tests. |
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ded5ce27ae
|
Fix bubbling of runtime requirements for #[require(...)] attribute (#16410)
# Objective Fixes #16406. Currently, the `#[require(...)]` attribute internally registers component requirements using `register_required_components_manual`. This is done recursively in a way where every requirement in the "inheritance tree" is added into a flat `RequiredComponents` hash map with component constructors and inheritance depths stored. However, this does not consider runtime requirements: if a plugins has already registered `C` as required by `B`, and a component `A` requires `B` through the macro attribute, spawning an entity with `A` won't add `C`. The `required_by` hash set for `C` doesn't have `A`, and the `RequiredComponents` of `A` don't have `C`. Intuitively, I would've thought that the macro attribute's requirements were always added *before* runtime requirements, and in that case I believe this shouldn't have been an issue. But the macro requirements are based on `Component::register_required_components`, which in a lot of cases (I think) is only called *after* the first time a bundle with the component is inserted. So if a runtime requirement is defined *before* this (as is often the case, during `Plugin::build`), the macro may not take it into account. ## Solution Register requirements inherited from the `required` component in `register_required_components_manual_unchecked`. ## Testing I added a test, essentially the same as in #16406, and it now passes. I also ran some of the tests in #16409, and they seem to work as expected. All the existing tests for required components pass. |
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3d6b24880e
|
Add insert_batch and variations (#15702)
# Objective `insert_or_spawn_batch` exists, but a version for just inserting doesn't - Closes #2693 - Closes #8384 - Adopts/supersedes #8600 ## Solution Add `insert_batch`, along with the most common `insert` variations: - `World::insert_batch` - `World::insert_batch_if_new` - `World::try_insert_batch` - `World::try_insert_batch_if_new` - `Commands::insert_batch` - `Commands::insert_batch_if_new` - `Commands::try_insert_batch` - `Commands::try_insert_batch_if_new` ## Testing Added tests, and added a benchmark for `insert_batch`. Performance is slightly better than `insert_or_spawn_batch` when only inserting:  <details> <summary>old benchmark</summary> This was before reworking it to remove the `UnsafeWorldCell`:  </details> --- ## Showcase Usage is the same as `insert_or_spawn_batch`: ``` use bevy_ecs::{entity::Entity, world::World, component::Component}; #[derive(Component)] struct A(&'static str); #[derive(Component, PartialEq, Debug)] struct B(f32); let mut world = World::new(); let entity_a = world.spawn_empty().id(); let entity_b = world.spawn_empty().id(); world.insert_batch([ (entity_a, (A("a"), B(0.0))), (entity_b, (A("b"), B(1.0))), ]); assert_eq!(world.get::<B>(entity_a), Some(&B(0.0))); ``` |
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d1bd46d45e
|
Deprecate get_or_spawn (#15652)
# Objective After merging retained rendering world #15320, we now have a good way of creating a link between worlds (*HIYAA intensifies*). This means that `get_or_spawn` is no longer necessary for that function. Entity should be opaque as the warning above `get_or_spawn` says. This is also part of #15459. I'm deprecating `get_or_spawn_batch` in a different PR in order to keep the PR small in size. ## Solution Deprecate `get_or_spawn` and replace it with `get_entity` in most contexts. If it's possible to query `&RenderEntity`, then the entity is synced and `render_entity.id()` is initialized in the render world. ## Migration Guide If you are given an `Entity` and you want to do something with it, use `Commands.entity(...)` or `World.entity(...)`. If instead you want to spawn something use `Commands.spawn(...)` or `World.spawn(...)`. If you are not sure if an entity exists, you can always use `get_entity` and match on the `Option<...>` that is returned. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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584d14808a
|
Allow World::entity family of functions to take multiple entities and get multiple references back (#15614)
# Objective Following the pattern established in #15593, we can reduce the API surface of `World` by providing a single function to grab both a singular entity reference, or multiple entity references. ## Solution The following functions can now also take multiple entity IDs and will return multiple entity references back: - `World::entity` - `World::get_entity` - `World::entity_mut` - `World::get_entity_mut` - `DeferredWorld::entity_mut` - `DeferredWorld::get_entity_mut` If you pass in X, you receive Y: - give a single `Entity`, receive a single `EntityRef`/`EntityWorldMut` (matches current behavior) - give a `[Entity; N]`/`&[Entity; N]` (array), receive an equally-sized `[EntityRef; N]`/`[EntityMut; N]` - give a `&[Entity]` (slice), receive a `Vec<EntityRef>`/`Vec<EntityMut>` - give a `&EntityHashSet`, receive a `EntityHashMap<EntityRef>`/`EntityHashMap<EntityMut>` Note that `EntityWorldMut` is only returned in the single-entity case, because having multiple at the same time would lead to UB. Also, `DeferredWorld` receives an `EntityMut` in the single-entity case because it does not allow structural access. ## Testing - Added doc-tests on `World::entity`, `World::entity_mut`, and `DeferredWorld::entity_mut` - Added tests for aliased mutability and entity existence --- ## Showcase <details> <summary>Click to view showcase</summary> The APIs for fetching `EntityRef`s and `EntityMut`s from the `World` have been unified. ```rust // This code will be referred to by subsequent code blocks. let world = World::new(); let e1 = world.spawn_empty().id(); let e2 = world.spawn_empty().id(); let e3 = world.spawn_empty().id(); ``` Querying for a single entity remains mostly the same: ```rust // 0.14 let eref: EntityRef = world.entity(e1); let emut: EntityWorldMut = world.entity_mut(e1); let eref: Option<EntityRef> = world.get_entity(e1); let emut: Option<EntityWorldMut> = world.get_entity_mut(e1); // 0.15 let eref: EntityRef = world.entity(e1); let emut: EntityWorldMut = world.entity_mut(e1); let eref: Result<EntityRef, Entity> = world.get_entity(e1); let emut: Result<EntityWorldMut, Entity> = world.get_entity_mut(e1); ``` Querying for multiple entities with an array has changed: ```rust // 0.14 let erefs: [EntityRef; 2] = world.many_entities([e1, e2]); let emuts: [EntityMut; 2] = world.many_entities_mut([e1, e2]); let erefs: Result<[EntityRef; 2], Entity> = world.get_many_entities([e1, e2]); let emuts: Result<[EntityMut; 2], QueryEntityError> = world.get_many_entities_mut([e1, e2]); // 0.15 let erefs: [EntityRef; 2] = world.entity([e1, e2]); let emuts: [EntityMut; 2] = world.entity_mut([e1, e2]); let erefs: Result<[EntityRef; 2], Entity> = world.get_entity([e1, e2]); let emuts: Result<[EntityMut; 2], EntityFetchError> = world.get_entity_mut([e1, e2]); ``` Querying for multiple entities with a slice has changed: ```rust let ids = vec![e1, e2, e3]); // 0.14 let erefs: Result<Vec<EntityRef>, Entity> = world.get_many_entities_dynamic(&ids[..]); let emuts: Result<Vec<EntityMut>, QueryEntityError> = world.get_many_entities_dynamic_mut(&ids[..]); // 0.15 let erefs: Result<Vec<EntityRef>, Entity> = world.get_entity(&ids[..]); let emuts: Result<Vec<EntityMut>, EntityFetchError> = world.get_entity_mut(&ids[..]); let erefs: Vec<EntityRef> = world.entity(&ids[..]); // Newly possible! let emuts: Vec<EntityMut> = world.entity_mut(&ids[..]); // Newly possible! ``` Querying for multiple entities with an `EntityHashSet` has changed: ```rust let set = EntityHashSet::from_iter([e1, e2, e3]); // 0.14 let emuts: Result<Vec<EntityMut>, QueryEntityError> = world.get_many_entities_from_set_mut(&set); // 0.15 let emuts: Result<EntityHashMap<EntityMut>, EntityFetchError> = world.get_entity_mut(&set); let erefs: Result<EntityHashMap<EntityRef>, EntityFetchError> = world.get_entity(&set); // Newly possible! let emuts: EntityHashMap<EntityMut> = world.entity_mut(&set); // Newly possible! let erefs: EntityHashMap<EntityRef> = world.entity(&set); // Newly possible! ``` </details> ## Migration Guide - `World::get_entity` now returns `Result<_, Entity>` instead of `Option<_>`. - Use `world.get_entity(..).ok()` to return to the previous behavior. - `World::get_entity_mut` and `DeferredWorld::get_entity_mut` now return `Result<_, EntityFetchError>` instead of `Option<_>`. - Use `world.get_entity_mut(..).ok()` to return to the previous behavior. - Type inference for `World::entity`, `World::entity_mut`, `World::get_entity`, `World::get_entity_mut`, `DeferredWorld::entity_mut`, and `DeferredWorld::get_entity_mut` has changed, and might now require the input argument's type to be explicitly written when inside closures. - The following functions have been deprecated, and should be replaced as such: - `World::many_entities` -> `World::entity::<[Entity; N]>` - `World::many_entities_mut` -> `World::entity_mut::<[Entity; N]>` - `World::get_many_entities` -> `World::get_entity::<[Entity; N]>` - `World::get_many_entities_dynamic` -> `World::get_entity::<&[Entity]>` - `World::get_many_entities_mut` -> `World::get_entity_mut::<[Entity; N]>` - The equivalent return type has changed from `Result<_, QueryEntityError>` to `Result<_, EntityFetchError>` - `World::get_many_entities_dynamic_mut` -> `World::get_entity_mut::<&[Entity]>1 - The equivalent return type has changed from `Result<_, QueryEntityError>` to `Result<_, EntityFetchError>` - `World::get_many_entities_from_set_mut` -> `World::get_entity_mut::<&EntityHashSet>` - The equivalent return type has changed from `Result<Vec<EntityMut>, QueryEntityError>` to `Result<EntityHashMap<EntityMut>, EntityFetchError>`. If necessary, you can still convert the `EntityHashMap` into a `Vec`. |
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8bf5d99d86
|
Add method to remove component and all required components for removed component (#15026)
## Objective The new Required Components feature (#14791) in Bevy allows spawning a fixed set of components with a single method with cool require macro. However, there's currently no corresponding method to remove all those components together. This makes it challenging to keep insertion and removal code in sync, especially for simple using cases. ```rust #[derive(Component)] #[require(Y)] struct X; #[derive(Component, Default)] struct Y; world.entity_mut(e).insert(X); // Spawns both X and Y world.entity_mut(e).remove::<X>(); world.entity_mut(e).remove::<Y>(); // We need to manually remove dependencies without any sync with the `require` macro ``` ## Solution Simplifies component management by providing operations for removal required components. This PR introduces simple 'footgun' methods to removes all components of this bundle and its required components. Two new methods are introduced: For Commands: ```rust commands.entity(e).remove_with_requires::<B>(); ``` For World: ```rust world.entity_mut(e).remove_with_requires::<B>(); ``` For performance I created new field in Bundels struct. This new field "contributed_bundle_ids" contains cached ids for dynamic bundles constructed from bundle_info.cintributed_components() ## Testing The PR includes three test cases: 1. Removing a single component with requirements using World. 2. Removing a bundle with requirements using World. 3. Removing a single component with requirements using Commands. 4. Removing a single component with **runtime** requirements using Commands These tests ensure the feature works as expected across different scenarios. ## Showcase Example: ```rust use bevy_ecs::prelude::*; #[derive(Component)] #[require(Y)] struct X; #[derive(Component, Default)] #[require(Z)] struct Y; #[derive(Component, Default)] struct Z; #[derive(Component)] struct W; let mut world = World::new(); // Spawn an entity with X, Y, Z, and W components let entity = world.spawn((X, W)).id(); assert!(world.entity(entity).contains::<X>()); assert!(world.entity(entity).contains::<Y>()); assert!(world.entity(entity).contains::<Z>()); assert!(world.entity(entity).contains::<W>()); // Remove X and required components Y, Z world.entity_mut(entity).remove_with_requires::<X>(); assert!(!world.entity(entity).contains::<X>()); assert!(!world.entity(entity).contains::<Y>()); assert!(!world.entity(entity).contains::<Z>()); assert!(world.entity(entity).contains::<W>()); ``` ## Motivation for PR #15580 ## Performance I made simple benchmark ```rust let mut world = World::default(); let entity = world.spawn_empty().id(); let steps = 100_000_000; let start = std::time::Instant::now(); for _ in 0..steps { world.entity_mut(entity).insert(X); world.entity_mut(entity).remove::<(X, Y, Z, W)>(); } let end = std::time::Instant::now(); println!("normal remove: {:?} ", (end - start).as_secs_f32()); println!("one remove: {:?} micros", (end - start).as_secs_f64() / steps as f64 * 1_000_000.0); let start = std::time::Instant::now(); for _ in 0..steps { world.entity_mut(entity).insert(X); world.entity_mut(entity).remove_with_requires::<X>(); } let end = std::time::Instant::now(); println!("remove_with_requires: {:?} ", (end - start).as_secs_f32()); println!("one remove_with_requires: {:?} micros", (end - start).as_secs_f64() / steps as f64 * 1_000_000.0); ``` Output: CPU: Amd Ryzen 7 2700x ```bash normal remove: 17.36135 one remove: 0.17361348299999999 micros remove_with_requires: 17.534006 one remove_with_requires: 0.17534005400000002 micros ``` NOTE: I didn't find any tests or mechanism in the repository to update BundleInfo after creating new runtime requirements with an existing BundleInfo. So this PR also does not contain such logic. ## Future work (outside this PR) Create cache system for fast removing components in "safe" mode, where "safe" mode is remove only required components that will be no longer required after removing root component. --------- Co-authored-by: a.yamaev <a.yamaev@smartengines.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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46180a75f8
|
System param for dynamic resources (#15189)
# Objective Support accessing dynamic resources in a dynamic system, including accessing them by component id. This is similar to how dynamic components can be queried using `Query<FilteredEntityMut>`. ## Solution Create `FilteredResources` and `FilteredResourcesMut` types that act similar to `FilteredEntityRef` and `FilteredEntityMut` and that can be used as system parameters. ## Example ```rust // Use `FilteredResourcesParamBuilder` to declare access to resources. let system = (FilteredResourcesParamBuilder::new(|builder| { builder.add_read::<B>().add_read::<C>(); }),) .build_state(&mut world) .build_system(resource_system); world.init_resource::<A>(); world.init_resource::<C>(); fn resource_system(res: FilteredResources) { // The resource exists, but we have no access, so we can't read it. assert!(res.get::<A>().is_none()); // The resource doesn't exist, so we can't read it. assert!(res.get::<B>().is_none()); // The resource exists and we have access, so we can read it. let c = res.get::<C>().unwrap(); // The type parameter can be left out if it can be determined from use. let c: Res<C> = res.get().unwrap(); } ``` ## Future Work As a follow-up PR, `ReflectResource` can be modified to take `impl Into<FilteredResources>`, similar to how `ReflectComponent` takes `impl Into<FilteredEntityRef>`. That will allow dynamic resources to be accessed using reflection. |
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acea4e7e6f
|
Better warnings about invalid parameters (#15500)
# Objective System param validation warnings should be configurable and default to "warn once" (per system). Fixes: #15391 ## Solution `SystemMeta` is given a new `ParamWarnPolicy` field. The policy decides whether warnings will be emitted by each system param when it fails validation. The policy is updated by the system after param validation fails. Example warning: ``` 2024-09-30T18:10:04.740749Z WARN bevy_ecs::system::function_system: System fallible_params::do_nothing_fail_validation will not run because it requested inaccessible system parameter Single<(), (With<Player>, With<Enemy>)> ``` Currently, only the first invalid parameter is displayed. Warnings can be disabled on function systems using `.param_never_warn()`. (there is also `.with_param_warn_policy(policy)`) ## Testing Ran `fallible_params` example. --------- Co-authored-by: SpecificProtagonist <vincentjunge@posteo.net> |
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f3e8ae03cd
|
Runtime required components (#15458)
# Objective Fixes #15367. Currently, required components can only be defined through the `require` macro attribute. While this should be used in most cases, there are also several instances where you may want to define requirements at runtime, commonly in plugins. Example use cases: - Require components only if the relevant optional plugins are enabled. For example, a `SleepTimer` component (for physics) is only relevant if the `SleepPlugin` is enabled. - Third party crates can define their own requirements for first party types. For example, "each `Handle<Mesh>` should require my custom rendering data components". This also gets around the orphan rule. - Generic plugins that add marker components based on the existence of other components, like a generic `ColliderPlugin<C: AnyCollider>` that wants to add a `ColliderMarker` component for all types of colliders. - This is currently relevant for the retained render world in #15320. The `ExtractComponentPlugin<C>` should add `SyncToRenderWorld` to all components that should be extracted. This is currently done with observers, which is more expensive than required components, and causes archetype moves. - Replace some built-in components with custom versions. For example, if `GlobalTransform` required `Transform` through `TransformPlugin`, but we wanted to use a `CustomTransform` type, we could replace `TransformPlugin` with our own plugin. (This specific example isn't good, but there are likely better use cases where this may be useful) See #15367 for more in-depth reasoning. ## Solution Add `register_required_components::<T, R>` and `register_required_components_with::<T, R>` methods for `Default` and custom constructors respectively. These methods exist on `App` and `World`. ```rust struct BirdPlugin; impl Plugin for BirdPlugin { fn plugin(app: &mut App) { // Make `Bird` require `Wings` with a `Default` constructor. app.register_required_components::<Bird, Wings>(); // Make `Wings` require `FlapSpeed` with a custom constructor. // Fun fact: Some hummingbirds can flutter their wings 80 times per second! app.register_required_components_with::<Wings, FlapSpeed>(|| FlapSpeed::from_duration(1.0 / 80.0)); } } ``` The custom constructor is a function pointer to match the `require` API, though it could take a raw value too. Requirement inheritance works similarly as with the `require` attribute. If `Bird` required `FlapSpeed` directly, it would take precedence over indirectly requiring it through `Wings`. The same logic applies to all levels of the inheritance tree. Note that registering the same component requirement more than once will panic, similarly to trying to add multiple component hooks of the same type to the same component. This avoids constructor conflicts and confusing ordering issues. ### Implementation Runtime requirements have two additional challenges in comparison to the `require` attribute. 1. The `require` attribute uses recursion and macros with clever ordering to populate hash maps of required components for each component type. The expected semantics are that "more specific" requirements override ones deeper in the inheritance tree. However, at runtime, there is no representation of how "specific" each requirement is. 2. If you first register the requirement `X -> Y`, and later register `Y -> Z`, then `X` should also indirectly require `Z`. However, `Y` itself doesn't know that it is required by `X`, so it's not aware that it should update the list of required components for `X`. My solutions to these problems are: 1. Store the depth in the inheritance tree for each entry of a given component's `RequiredComponents`. This is used to determine how "specific" each requirement is. For `require`-based registration, these depths are computed as part of the recursion. 2. Store and maintain a `required_by` list in each component's `ComponentInfo`, next to `required_components`. For `require`-based registration, these are also added after each registration, as part of the recursion. When calling `register_required_components`, it works as follows: 1. Get the required components of `Foo`, and check that `Bar` isn't already a *direct* requirement. 3. Register `Bar` as a required component for `Foo`, and add `Foo` to the `required_by` list for `Bar`. 4. Find and register all indirect requirements inherited from `Bar`, adding `Foo` to the `required_by` list for each component. 5. Iterate through components that require `Foo`, registering the new inherited requires for them as indirect requirements. The runtime registration is likely slightly more expensive than the `require` version, but it is a one-time cost, and quite negligible in practice, unless projects have hundreds or thousands of runtime requirements. I have not benchmarked this however. This does also add a small amount of extra cost to the `require` attribute for updating `required_by` lists, but I expect it to be very minor. ## Testing I added some tests that are copies of the `require` versions, as well as some tests that are more specific to the runtime implementation. I might add a few more tests though. ## Discussion - Is `register_required_components` a good name? Originally I went for `register_component_requirement` to be consistent with `register_component_hooks`, but the general feature is often referred to as "required components", which is why I changed it to `register_required_components`. - Should we *not* panic for duplicate requirements? If so, should they just be ignored, or should the latest registration overwrite earlier ones? - If we do want to panic for duplicate, conflicting registrations, should we at least not panic if the registrations are *exactly* the same, i.e. same component and same constructor? The current implementation panics for all duplicate direct registrations regardless of the constructor. ## Next Steps - Allow `register_required_components` to take a `Bundle` instead of a single required component. - I could also try to do it in this PR if that would be preferable. - Not directly related, but archetype invariants? |
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fc93e13c36
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Populated (query) system param (#15488)
# Objective Add a `Populated` system parameter that acts like `Query`, but prevents system from running if there are no matching entities. Fixes: #15302 ## Solution Implement the system param which newtypes the `Query`. The only change is new validation, which fails if query is empty. The new system param is used in `fallible_params` example. ## Testing Ran `fallible_params` example. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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f97eba2082
|
Add VisitEntities for generic and reflectable Entity iteration (#15425)
# Objective - Provide a generic and _reflectable_ way to iterate over contained entities ## Solution Adds two new traits: * `VisitEntities`: Reflectable iteration, accepts a closure rather than producing an iterator. Implemented by default for `IntoIterator` implementing types. A proc macro is also provided. * A `Mut` variant of the above. Its derive macro uses the same field attribute to avoid repetition. ## Testing Added a test for `VisitEntities` that also transitively tests its derive macro as well as the default `MapEntities` impl. |
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8316d89699
|
rename QuerySingle to Single (#15507)
# Objective - Fixes #15504 |
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c1486654d7
|
QuerySingle family of system params (#15476)
# Objective Add the following system params: - `QuerySingle<D, F>` - Valid if only one matching entity exists, - `Option<QuerySingle<D, F>>` - Valid if zero or one matching entity exists. As @chescock pointed out, we don't need `Mut` variants. Fixes: #15264 ## Solution Implement the type and both variants of system params. Also implement `ReadOnlySystemParam` for readonly queries. Added a new ECS example `fallible_params` which showcases `SingleQuery` usage. In the future we might want to add `NonEmptyQuery`, `NonEmptyEventReader` and `Res` to it (or maybe just stop at mentioning it). ## Testing Tested with the example. There is a lot of warning spam so we might want to implement #15391. |
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d70595b667
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Add core and alloc over std Lints (#15281)
# Objective - Fixes #6370 - Closes #6581 ## Solution - Added the following lints to the workspace: - `std_instead_of_core` - `std_instead_of_alloc` - `alloc_instead_of_core` - Used `cargo +nightly fmt` with [item level use formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Item%5C%3A) to split all `use` statements into single items. - Used `cargo clippy --workspace --all-targets --all-features --fix --allow-dirty` to _attempt_ to resolve the new linting issues, and intervened where the lint was unable to resolve the issue automatically (usually due to needing an `extern crate alloc;` statement in a crate root). - Manually removed certain uses of `std` where negative feature gating prevented `--all-features` from finding the offending uses. - Used `cargo +nightly fmt` with [crate level use formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Crate%5C%3A) to re-merge all `use` statements matching Bevy's previous styling. - Manually fixed cases where the `fmt` tool could not re-merge `use` statements due to conditional compilation attributes. ## Testing - Ran CI locally ## Migration Guide The MSRV is now 1.81. Please update to this version or higher. ## Notes - This is a _massive_ change to try and push through, which is why I've outlined the semi-automatic steps I used to create this PR, in case this fails and someone else tries again in the future. - Making this change has no impact on user code, but does mean Bevy contributors will be warned to use `core` and `alloc` instead of `std` where possible. - This lint is a critical first step towards investigating `no_std` options for Bevy. --------- Co-authored-by: François Mockers <francois.mockers@vleue.com> |
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35d10866b8
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Rename init_component & friends (#15454)
# Objective - Fixes #15451 ## Migration Guide - `World::init_component` has been renamed to `register_component`. - `World::init_component_with_descriptor` has been renamed to `register_component_with_descriptor`. - `World::init_bundle` has been renamed to `register_bundle`. - `Components::init_component` has been renamed to `register_component`. - `Components::init_component_with_descriptor` has been renamed to `register_component_with_descriptor`. - `Components::init_resource` has been renamed to `register_resource`. - `Components::init_non_send` had been renamed to `register_non_send`. |