# Objective
Fixes#12549. WorldCell's support of everything a World can do is
incomplete, and represents an alternative, potentially confusing, and
less performant way of pulling multiple fetches from a `World`. The
typical approach is to use `SystemState` for a runtime cached and safe
way, or `UnsafeWorldCell` if the use of `unsafe` is tolerable.
## Solution
Remove it!
---
## Changelog
Removed: `WorldCell`
Removed: `World::cell`
## Migration Guide
`WorldCell` has been removed. If you were using it to fetch multiple
distinct values from a `&mut World`, use `SystemState` by calling
`SystemState::get` instead. Alternatively, if `SystemState` cannot be
used, `UnsafeWorldCell` can instead be used in unsafe contexts.
# Objective
Provide component access to `&'w T`, `Ref<'w, T>`, `Mut<'w, T>`,
`Ptr<'w>` and `MutUntyped<'w>` from `EntityMut<'w>`/`EntityWorldMut<'w>`
with the world `'w` lifetime instead of `'_`.
Fixes#12417
## Solution
Add `into_` prefixed methods for `EntityMut<'w>`/`EntityWorldMut<'w>`
that consume `self` and returns component access with the world `'w`
lifetime unlike the `get_` prefixed methods that takes `&'a self` and
returns component access with `'a` lifetime.
Methods implemented:
- EntityMut::into_borrow
- EntityMut::into_ref
- EntityMut::into_mut
- EntityMut::into_borrow_by_id
- EntityMut::into_mut_by_id
- EntityWorldMut::into_borrow
- EntityWorldMut::into_ref
- EntityWorldMut::into_mut
- EntityWorldMut::into_borrow_by_id
- EntityWorldMut::into_mut_by_id
# Objective
`QueryState::archetype_component_access` is only really ever used to
extend `SystemMeta`'s. It can be removed to save some memory for every
`Query` in an app.
## Solution
* Remove it.
* Have `new_archetype` pass in a `&mut Access<ArchetypeComponentId>`
instead and pull it from `SystemMeta` directly.
* Split `QueryState::new` from `QueryState::new_with_access` and a
common `QueryState::new_uninitialized`.
* Split `new_archetype` into an internal and public version. Call the
internal version in `update_archetypes`.
This should make it faster to construct new QueryStates, and by proxy
lenses and joins as well.
`matched_tables` also similarly is only used to deduplicate inserting
into `matched_table_ids`. If we can find another efficient way to do so,
it might also be worth removing.
The [generated
assembly](https://github.com/james7132/bevy_asm_tests/compare/main...remove-query-state-archetype-component-access#diff-496530101f0b16e495b7e9b77c0e906ae3068c8adb69ed36c92d5a1be5a9efbe)
reflects this well, with all of the access related updates in
`QueryState` being removed.
---
## Changelog
Removed: `QueryState::archetype_component_access`.
Changed: `QueryState::new_archetype` now takes a `&mut
Access<ArchetypeComponentId>` argument, which will be updated with the
new accesses.
Changed: `QueryState::update_archetype_component_access` now takes a
`&mut Access<ArchetypeComponentId>` argument, which will be updated with
the new accesses.
## Migration Guide
TODO
# Objective
Improve code quality involving fixedbitset.
## Solution
Update to fixedbitset 0.5. Use the new `grow_and_insert` function
instead of `grow` and `insert` functions separately.
This should also speed up most of the set operations involving
fixedbitset. They should be ~2x faster, but testing this against the
stress tests seems to show little to no difference. The multithreaded
executor doesn't seem to be all that much faster in many_cubes and
many_foxes. These use cases are likely dominated by other operations or
the bitsets aren't big enough to make them the bottleneck.
This introduces a duplicate dependency due to petgraph and wgpu, but the
former may take some time to update.
## Changelog
Removed: `Access::grow`
## Migration Guide
`Access::grow` has been removed. It's no longer needed. Remove all
references to it.
# Objective
Fixes#12139
## Solution
- Derive `Debug` impl for `Entity`
- Add impl `Display` for `Entity`
- Add `entity_display` test to check the output contains all required
info
I decided to go with `0v0|1234` format as opposed to the `0v0[1234]`
which was initially discussed in the issue.
My rationale for this is that `[1234]` may be confused for index values,
which may be common in logs, and so searching for entities by text would
become harder. I figured `|1234` would help the entity IDs stand out
more.
Additionally, I'm a little concerned that this change is gonna break
existing logging for projects because `Debug` is now going to be a
multi-line output. But maybe this is ok.
We could implement `Debug` to be a single-line output, but then I don't
see why it would be different from `Display` at all.
@alice-i-cecile Let me know if we'd like to make any changes based on
these points.
# Objective
`System<f32>` currently does not implement `Eq` even though it should
## Solution
Manually implement `Eq` like other traits are manually implemented
# Objective
- Add a way to combine 2 queries together in a similar way to
`Query::transmute_lens`
- Fixes#1658
## Solution
- Use a similar method to query transmute, but take the intersection of
matched archetypes between the 2 queries and the union of the accesses
to create the new underlying QueryState.
---
## Changelog
- Add query joins
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Fix#10876. Improve `Query` and `QueryState`'s docs.
## Solution
Explicitly denote that Query is always guaranteed to return results from
all matching entities once and only once for each entity, and that
iteration order is not guaranteed in any way.
# Objective
Remove Bevy internals from backtraces
## Solution
Executors insert `__rust_begin_short_backtrace` into the callstack
before running a system.
<details>
<summary>Example current output</summary>
```
thread 'Compute Task Pool (3)' panicked at src/main.rs:7:33:
Foo
stack backtrace:
0: rust_begin_unwind
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:647:5
1: core::panicking::panic_fmt
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/panicking.rs:72:14
2: foo::main::{{closure}}
at ./src/main.rs:7:33
3: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/ops/function.rs:294:13
4: <Func as bevy_ecs::system::function_system::SystemParamFunction<fn() .> Out>>::run::call_inner
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/system/function_system.rs:661:21
5: <Func as bevy_ecs::system::function_system::SystemParamFunction<fn() .> Out>>::run
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/system/function_system.rs:664:17
6: <bevy_ecs::system::function_system::FunctionSystem<Marker,F> as bevy_ecs::system::system::System>::run_unsafe
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/system/function_system.rs:504:19
7: bevy_ecs::schedule::executor::multi_threaded::ExecutorState::spawn_system_task::{{closure}}::{{closure}}
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/schedule/executor/multi_threaded.rs:621:26
8: core::ops::function::FnOnce::call_once
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/ops/function.rs:250:5
9: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/panic/unwind_safe.rs:272:9
10: std::panicking::try::do_call
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:554:40
11: __rust_try
12: std::panicking::try
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:518:19
13: std::panic::catch_unwind
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panic.rs:142:14
14: bevy_ecs::schedule::executor::multi_threaded::ExecutorState::spawn_system_task::{{closure}}
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/schedule/executor/multi_threaded.rs:614:23
15: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::future::future::Future>::poll
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/panic/unwind_safe.rs:297:9
16: <futures_lite::future::CatchUnwind<F> as core::future::future::Future>::poll::{{closure}}
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/futures-lite-2.2.0/src/future.rs:588:42
17: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/panic/unwind_safe.rs:272:9
18: std::panicking::try::do_call
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:554:40
19: __rust_try
20: std::panicking::try
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:518:19
21: std::panic::catch_unwind
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panic.rs:142:14
22: <futures_lite::future::CatchUnwind<F> as core::future::future::Future>::poll
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/futures-lite-2.2.0/src/future.rs:588:9
23: async_executor::Executor::spawn::{{closure}}
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/async-executor-1.8.0/src/lib.rs:158:20
24: async_task::raw::RawTask<F,T,S,M>::run::{{closure}}
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/async-task-4.7.0/src/raw.rs:550:21
25: core::ops::function::FnOnce::call_once
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/ops/function.rs:250:5
26: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/panic/unwind_safe.rs:272:9
27: std::panicking::try::do_call
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:554:40
28: __rust_try
29: std::panicking::try
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:518:19
30: std::panic::catch_unwind
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panic.rs:142:14
31: async_task::raw::RawTask<F,T,S,M>::run
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/async-task-4.7.0/src/raw.rs:549:23
32: async_task::runnable::Runnable<M>::run
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/async-task-4.7.0/src/runnable.rs:781:18
33: async_executor::Executor::run::{{closure}}::{{closure}}
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/async-executor-1.8.0/src/lib.rs:254:21
34: <futures_lite::future::Or<F1,F2> as core::future::future::Future>::poll
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/futures-lite-2.2.0/src/future.rs:449:33
35: async_executor::Executor::run::{{closure}}
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/async-executor-1.8.0/src/lib.rs:261:32
36: futures_lite::future::block_on::{{closure}}
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/futures-lite-2.2.0/src/future.rs:99:19
37: std:🧵:local::LocalKey<T>::try_with
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/thread/local.rs:286:16
38: std:🧵:local::LocalKey<T>::with
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/thread/local.rs:262:9
39: futures_lite::future::block_on
at /home/vj/.cargo/registry/src/index.crates.io-6f17d22bba15001f/futures-lite-2.2.0/src/future.rs:78:5
40: bevy_tasks::task_pool::TaskPool::new_internal::{{closure}}::{{closure}}::{{closure}}::{{closure}}
at /home/vj/workspace/rust/bevy/crates/bevy_tasks/src/task_pool.rs:180:37
41: std::panicking::try::do_call
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:554:40
42: __rust_try
43: std::panicking::try
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:518:19
44: std::panic::catch_unwind
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panic.rs:142:14
45: bevy_tasks::task_pool::TaskPool::new_internal::{{closure}}::{{closure}}::{{closure}}
at /home/vj/workspace/rust/bevy/crates/bevy_tasks/src/task_pool.rs:174:43
46: std:🧵:local::LocalKey<T>::try_with
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/thread/local.rs:286:16
47: std:🧵:local::LocalKey<T>::with
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/thread/local.rs:262:9
48: bevy_tasks::task_pool::TaskPool::new_internal::{{closure}}::{{closure}}
at /home/vj/workspace/rust/bevy/crates/bevy_tasks/src/task_pool.rs:167:25
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
Encountered a panic in system `foo::main::{{closure}}`!
Encountered a panic in system `bevy_app::main_schedule::Main::run_main`!
get on your knees and beg mommy for forgiveness you pervert~ 💖
```
</details>
<details>
<summary>Example output with this PR</summary>
```
Panic at src/main.rs:7:33:
Foo
stack backtrace:
0: rust_begin_unwind
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/std/src/panicking.rs:647:5
1: core::panicking::panic_fmt
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/panicking.rs:72:14
2: foo::main::{{closure}}
at ./src/main.rs:7:59
3: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
at /rustc/8ace7ea1f7cbba7b4f031e66c54ca237a0d65de6/library/core/src/ops/function.rs:294:13
4: <Func as bevy_ecs::system::function_system::SystemParamFunction<fn() .> Out>>::run::call_inner
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/system/function_system.rs:661:21
5: <Func as bevy_ecs::system::function_system::SystemParamFunction<fn() .> Out>>::run
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/system/function_system.rs:664:17
6: <bevy_ecs::system::function_system::FunctionSystem<Marker,F> as bevy_ecs::system::system::System>::run_unsafe
at /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/system/function_system.rs:504:19
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
Encountered a panic in system `foo::main::{{closure}}`!
Encountered a panic in system `bevy_app::main_schedule::Main::run_main`!
```
</details>
Full backtraces (`RUST_BACKTRACE=full`) are unchanged.
## Alternative solutions
Write a custom panic hook. This could potentially let use exclude a few
more callstack frames but requires a dependency on `backtrace` and is
incompatible with user-provided panic hooks.
---
## Changelog
- Backtraces now exclude many Bevy internals (unless
`RUST_BACKTRACE=full` is used)
---------
Co-authored-by: James Liu <contact@jamessliu.com>
# Objective
Fix missing `TextBundle` (and many others) which are present in the main
crate as default features but optional in the sub-crate. See:
- https://docs.rs/bevy/0.13.0/bevy/ui/node_bundles/index.html
- https://docs.rs/bevy_ui/0.13.0/bevy_ui/node_bundles/index.html
~~There are probably other instances in other crates that I could track
down, but maybe "all-features = true" should be used by default in all
sub-crates? Not sure.~~ (There were many.) I only noticed this because
rust-analyzer's "open docs" features takes me to the sub-crate, not the
main one.
## Solution
Add "all-features = true" to docs.rs metadata for crates that use
features.
## Changelog
### Changed
- Unified features documented on docs.rs between main crate and
sub-crates
# Objective
Make bevy_utils less of a compilation bottleneck. Tackle #11478.
## Solution
* Move all of the directly reexported dependencies and move them to
where they're actually used.
* Remove the UUID utilities that have gone unused since `TypePath` took
over for `TypeUuid`.
* There was also a extraneous bytemuck dependency on `bevy_core` that
has not been used for a long time (since `encase` became the primary way
to prepare GPU buffers).
* Remove the `all_tuples` macro reexport from bevy_ecs since it's
accessible from `bevy_utils`.
---
## Changelog
Removed: Many of the reexports from bevy_utils (petgraph, uuid, nonmax,
smallvec, and thiserror).
Removed: bevy_core's reexports of bytemuck.
## Migration Guide
bevy_utils' reexports of petgraph, uuid, nonmax, smallvec, and thiserror
have been removed.
bevy_core' reexports of bytemuck's types has been removed.
Add them as dependencies in your own crate instead.
# Objective
Following #10756, we're now using raw pointers in BundleInserter and
BundleSpawner. This is primarily to get around the need to split the
borrow on the World, but it leaves a lot to be desired in terms of
safety guarantees. There's no type level guarantee the code can't
dereference a null pointer, and it's restoring them to borrows fairly
liberally within the associated functions.
## Solution
* Replace the pointers with `NonNull` and a new `bevy_ptr::ConstNonNull`
that only allows conversion back to read-only borrows
* Remove the closure to avoid potentially aliasing through the closure
by restructuring the match expression.
* Move all conversions back into borrows as far up as possible to ensure
that the borrow checker is at least locally followed.
# Objective
`initialize_resource<T>` and it's non-send equivalent is only used in
two locations each. Fix#6285.
## Solution
Remove them, replace their calls with their internals. Cut down on a bit
of generic codegen.
This does mean that `initialize_resource_internal` is now `pub(crate)`,
but that's likely OK given that only one variant will remain once
NonSend resources are removed from the World.
# Objective
When doing a final pass for #3362, it appeared that `ComponentStorage`
as a trait, the two types implementing it, and the associated type on
`Component` aren't really necessary anymore. This likely was due to an
earlier constraint on the use of consts in traits, but that definitely
doesn't seem to be a problem in Rust 1.76.
## Solution
Remove them.
---
## Changelog
Changed: `Component::Storage` has been replaced with
`Component::STORAGE_TYPE` as a const.
Removed: `bevy::ecs::component::ComponentStorage` trait
Removed: `bevy::ecs::component::TableStorage` struct
Removed: `bevy::ecs::component::SparseSetStorage` struct
## Migration Guide
If you were manually implementing `Component` instead of using the
derive macro, replace the associated `Storage` associated type with the
`STORAGE_TYPE` const:
```rust
// in Bevy 0.13
impl Component for MyComponent {
type Storage = TableStorage;
}
// in Bevy 0.14
impl Component for MyComponent {
const STORAGE_TYPE: StorageType = StorageType::Table;
}
```
Component is no longer object safe. If you were relying on `&dyn
Component`, `Box<dyn Component>`, etc. please [file an issue
](https://github.com/bevyengine/bevy/issues) to get [this
change](https://github.com/bevyengine/bevy/pull/12311) reverted.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
- Explain it is flushed in the same schedule run (was not obvious to me)
- Point to `apply_deferred` example
- Remove mentions of `System::apply_deferred` and
`Schedule::apply_deferred` which are probably too low level for the most
users
Co-authored-by: James Liu <contact@jamessliu.com>
# Objective
- The doc example for `World::run_system_with_input` mistakenly
indicates that systems share state
- Some of the doc example code is unnecessary and/or could be cleaned up
## Solution
Replace the incorrect result value for the correct one in the doc
example. I also went with an explicit `assert_eq` check as it presents
the same information but can be validated by CI via doc tests.
Also removed some unnecessary code, such as the `Resource` derives on
`Counter`. In fact, I just replaced `Counter` with a `u8` in the
`Local`. I think it makes the example a little cleaner.
---
## Changelog
- Update docs for `World::run_system` and `World::run_system_with_input`
# Objective
Adoption of #2104 and #11843. The `Option<usize>` wastes 3-7 bytes of
memory per potential entry, and represents a scaling memory overhead as
the ID space grows.
The goal of this PR is to reduce memory usage without significantly
impacting common use cases.
Co-Authored By: @NathanSWard
Co-Authored By: @tygyh
## Solution
Replace `usize` in `SparseSet`'s sparse array with
`nonmax::NonMaxUsize`. NonMaxUsize wraps a NonZeroUsize, and applies a
bitwise NOT to the value when accessing it. This allows the compiler to
niche the value and eliminate the extra padding used for the `Option`
inside the sparse array, while moving the niche value from 0 to
usize::MAX instead.
Checking the [diff in x86 generated
assembly](6e4da653cc),
this change actually results in fewer instructions generated. One
potential downside is that it seems to have moved a load before a
branch, which means we may be incurring a cache miss even if the element
is not there.
Note: unlike #2104 and #11843, this PR only targets the metadata stores
for the ECS and not the component storage itself. Due to #9907 targeting
`Entity::generation` instead of `Entity::index`, `ComponentSparseSet`
storing only up to `u32::MAX` elements would become a correctness issue.
This will come with a cost when inserting items into the SparseSet, as
now there is a potential for a panic. These cost are really only
incurred when constructing a new Table, Archetype, or Resource that has
never been seen before by the World. All operations that are fairly cold
and not on any particular hotpath, even for command application.
---
## Changelog
Changed: `SparseSet` now can only store up to `usize::MAX - 1` elements
instead of `usize::MAX`.
Changed: `SparseSet` now uses 33-50% less memory overhead per stored
item.
# Objective
Fixes https://github.com/bevyengine/bevy/issues/11628
## Migration Guide
`Command` and `CommandQueue` have migrated from `bevy_ecs::system` to
`bevy_ecs::world`, so `use bevy_ecs::world::{Command, CommandQueue};`
when necessary.
# Objective
bevy_ecs has been developed with a de facto assumption that `Entity` is
to be treated as an opaque identifier by external users, and that its
internal representation is readable but in no way guaranteed to be
stable between versions of bevy_ecs.
This hasn't been clear to users, and the functions on the type that
expose its guts speak a different story.
## Solution
Explicitly document the lack of stability here and define internal
representation changes as a non-breaking change under SemVer. Give it
the same treatment that the standard lib gives `TypeId`.
# Objective
- Fix mismatch between the `Component` trait method and the `World`
method.
## Solution
- Replace init_component_info with register_component_hooks.
# Objective
- Provide a reliable and performant mechanism to allows users to keep
components synchronized with external sources: closing/opening sockets,
updating indexes, debugging etc.
- Implement a generic mechanism to provide mutable access to the world
without allowing structural changes; this will not only be used here but
is a foundational piece for observers, which are key for a performant
implementation of relations.
## Solution
- Implement a new type `DeferredWorld` (naming is not important,
`StaticWorld` is also suitable) that wraps a world pointer and prevents
user code from making any structural changes to the ECS; spawning
entities, creating components, initializing resources etc.
- Add component lifecycle hooks `on_add`, `on_insert` and `on_remove`
that can be assigned callbacks in user code.
---
## Changelog
- Add new `DeferredWorld` type.
- Add new world methods: `register_component::<T>` and
`register_component_with_descriptor`. These differ from `init_component`
in that they provide mutable access to the created `ComponentInfo` but
will panic if the component is already in any archetypes. These
restrictions serve two purposes:
1. Prevent users from defining hooks for components that may already
have associated hooks provided in another plugin. (a use case better
served by observers)
2. Ensure that when an `Archetype` is created it gets the appropriate
flags to early-out when triggering hooks.
- Add methods to `ComponentInfo`: `on_add`, `on_insert` and `on_remove`
to be used to register hooks of the form `fn(DeferredWorld, Entity,
ComponentId)`
- Modify `BundleInserter`, `BundleSpawner` and `EntityWorldMut` to
trigger component hooks when appropriate.
- Add bit flags to `Archetype` indicating whether or not any contained
components have each type of hook, this can be expanded for other flags
as needed.
- Add `component_hooks` example to illustrate usage. Try it out! It's
fun to mash keys.
## Safety
The changes to component insertion, removal and deletion involve a large
amount of unsafe code and it's fair for that to raise some concern. I
have attempted to document it as clearly as possible and have confirmed
that all the hooks examples are accepted by `cargo miri` as not causing
any undefined behavior. The largest issue is in ensuring there are no
outstanding references when passing a `DeferredWorld` to the hooks which
requires some use of raw pointers (as was already happening to some
degree in those places) and I have taken some time to ensure that is the
case but feel free to let me know if I've missed anything.
## Performance
These changes come with a small but measurable performance cost of
between 1-5% on `add_remove` benchmarks and between 1-3% on `insert`
benchmarks. One consideration to be made is the existence of the current
`RemovedComponents` which is on average more costly than the addition of
`on_remove` hooks due to the early-out, however hooks doesn't completely
remove the need for `RemovedComponents` as there is a chance you want to
respond to the removal of a component that already has an `on_remove`
hook defined in another plugin, so I have not removed it here. I do
intend to deprecate it with the introduction of observers in a follow up
PR.
## Discussion Questions
- Currently `DeferredWorld` implements `Deref` to `&World` which makes
sense conceptually, however it does cause some issues with rust-analyzer
providing autocomplete for `&mut World` references which is annoying.
There are alternative implementations that may address this but involve
more code churn so I have attempted them here. The other alternative is
to not implement `Deref` at all but that leads to a large amount of API
duplication.
- `DeferredWorld`, `StaticWorld`, something else?
- In adding support for hooks to `EntityWorldMut` I encountered some
unfortunate difficulties with my desired API. If commands are flushed
after each call i.e. `world.spawn() // flush commands .insert(A) //
flush commands` the entity may be despawned while `EntityWorldMut` still
exists which is invalid. An alternative was then to add
`self.world.flush_commands()` to the drop implementation for
`EntityWorldMut` but that runs into other problems for implementing
functions like `into_unsafe_entity_cell`. For now I have implemented a
`.flush()` which will flush the commands and consume `EntityWorldMut` or
users can manually run `world.flush_commands()` after using
`EntityWorldMut`.
- In order to allowing querying on a deferred world we need
implementations of `WorldQuery` to not break our guarantees of no
structural changes through their `UnsafeWorldCell`. All our
implementations do this, but there isn't currently any safety
documentation specifying what is or isn't allowed for an implementation,
just for the caller, (they also shouldn't be aliasing components they
didn't specify access for etc.) is that something we should start doing?
(see 10752)
Please check out the example `component_hooks` or the tests in
`bundle.rs` for usage examples. I will continue to expand this
description as I go.
See #10839 for a more ergonomic API built on top of this one that isn't
subject to the same restrictions and supports `SystemParam` dependency
injection.
# Objective
- In #9623 I forgot to change the `FromWorld` requirement for
`ReflectResource`, fix that;
- Fix#12129
## Solution
- Use the same approach as in #9623 to try using `FromReflect` and
falling back to the `ReflectFromWorld` contained in the `TypeRegistry`
provided
- Just reflect `Resource` on `State<S>` since now that's possible
without introducing new bounds.
---
## Changelog
- `ReflectResource`'s `FromType<T>` implementation no longer requires
`T: FromWorld`, but instead now requires `FromReflect`.
- `ReflectResource::insert`, `ReflectResource::apply_or_insert` and
`ReflectResource::copy` now take an extra `&TypeRegistry` parameter.
## Migration Guide
- Users of `#[reflect(Resource)]` will need to also implement/derive
`FromReflect` (should already be the default).
- Users of `#[reflect(Resource)]` may now want to also add `FromWorld`
to the list of reflected traits in case their `FromReflect`
implementation may fail.
- Users of `ReflectResource` will now need to pass a `&TypeRegistry` to
its `insert`, `apply_or_insert` and `copy` methods.
# Objective
`downcast-rs` is not used within bevy_ecs. This is probably a remnant
from before Schedule v3 landed, since stages needed the downcasting.
## Solution
Remove it.
# Objective
Memory usage optimisation
## Solution
`HashMap` and `HashSet`'s keys are immutable. So using mutable types
like `String`, `Vec<T>`, or `PathBuf` as a key is a waste of memory:
they have an extra `usize` for their capacity and may have spare
capacity.
This PR replaces these types by their immutable equivalents `Box<str>`,
`Box<[T]>`, and `Box<Path>`.
For more context, I recommend watching the [Use Arc Instead of
Vec](https://www.youtube.com/watch?v=A4cKi7PTJSs) video.
---------
Co-authored-by: James Liu <contact@jamessliu.com>
# Objective
- Avoid misspellings throughout the codebase by using
[`typos`](https://github.com/crate-ci/typos) in CI
Inspired by https://github.com/gfx-rs/wgpu/pull/5191
Typos is a minimal code speller written in rust that finds and corrects
spelling mistakes among source code.
- Fast enough to run on monorepos
- Low false positives so you can run on PRs
## Solution
- Use
[typos-action](https://github.com/marketplace/actions/typos-action) in
CI
- Add how to use typos in the Contribution Guide
---------
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Joona Aalto <jondolf.dev@gmail.com>
# Objective
Right now when using egui, systems are inserted without any identifier
and to the root. I'd like to name those systems and insert them as
children to a root entity. This helps to keep the editor organized.
## Solution
- Although the `SystemId` is documented as an opaque type, examples
depicted above benefit from tear down of the abstraction.
---
## Changelog
### Added
- Implemented `From<SystemId>` for `Entity`
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Add Archetype::component_count utility method
# Objective
I wanted a method to count components on an archetype without iterating
over them.
## Solution
Added `Archetype::component_count`
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
The multi-threaded executor currently runs in a dedicated task on a
single thread. When a system finishes running, it needs to notify that
task and wait for the thread to be available and running before the
executor can process the completion.
See #8304
## Solution
Run the multi-threaded executor at the end of each system task. This
allows it to run immediately instead of needing to wait for the main
thread to wake up. Move the mutable executor state into a separate
struct and wrap it in a mutex so it can be shared among the worker
threads.
While this should be faster in theory, I don't actually know how to
measure the performance impact myself.
---------
Co-authored-by: James Liu <contact@jamessliu.com>
Co-authored-by: Mike <mike.hsu@gmail.com>
# Objective
- A tiny nit I noticed; I think the type of these function is
`EntityCommand`, not `Command`
Co-authored-by: Charles Bournhonesque <cbournhonesque@snapchat.com>
# Objective
- Add the new `-Zcheck-cfg` checks to catch more warnings
- Fixes#12091
## Solution
- Create a new `cfg-check` to the CI that runs `cargo check -Zcheck-cfg
--workspace` using cargo nightly (and fails if there are warnings)
- Fix all warnings generated by the new check
---
## Changelog
- Remove all redundant imports
- Fix cfg wasm32 targets
- Add 3 dead code exceptions (should StandardColor be unused?)
- Convert ios_simulator to a feature (I'm not sure if this is the right
way to do it, but the check complained before)
## Migration Guide
No breaking changes
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Fixes#11821.
## Solution
* Run `System::apply_deferred` in `System::run` after executing the
system.
* Switch to using `System::run_unsafe` in `SingleThreadedExecutor` to
preserve the current behavior.
* Remove the `System::apply_deferred` in `SimpleExecutor` as it's now
redundant.
* Remove the `System::apply_deferred` when running one-shot systems, as
it's now redundant.
---
## Changelog
Changed: `System::run` will now immediately apply deferred system params
after running the system.
## Migration Guide
`System::run` will now always run `System::apply_deferred` immediately
after running the system now. If you were running systems and then
applying their deferred buffers at a later point in time, you can
eliminate the latter.
```rust
// in 0.13
system.run(world);
// .. sometime later ...
system.apply_deferred(world);
// in 0.14
system.run(world);
```
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Since #9822, `SimpleExecutor` panics when an automatic sync point is
inserted:
```rust
let mut sched = Schedule::default();
sched.set_executor_kind(ExecutorKind::Simple);
sched.add_systems((|_: Commands| (), || ()).chain());
sched.run(&mut World::new());
```
```
System's param_state was not found. Did you forget to initialize this system before running it?
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Encountered a panic in system `bevy_ecs::schedule::executor::apply_deferred`!
```
## Solution
Don't try to run the `apply_deferred` system.
# Objective
- Part of #11590
- Fix `unsafe_op_in_unsafe_fn` for trivial cases in bevy_ecs
## Solution
Fix `unsafe_op_in_unsafe_fn` in bevy_ecs for trivial cases, i.e., add an
`unsafe` block when the safety comment already exists or add a comment
like "The invariants are uphold by the caller".
---------
Co-authored-by: James Liu <contact@jamessliu.com>
## Objective
Always have `some_system.into_system().type_id() ==
some_system.into_system_set().system_type().unwrap()`.
System sets have a `fn system_type() -> Option<TypeId>` that is
implemented by `SystemTypeSet` to returning the TypeId of the system's
function type. This was implemented in
https://github.com/bevyengine/bevy/pull/7715 and is used in
`bevy_mod_debugdump` to handle `.after(function)` constraints.
Back then, `System::type_id` always also returned the type id of the
function item, not of `FunctionSystem<M, F>`.
https://github.com/bevyengine/bevy/pull/11728 changes the behaviour of
`System::type_id` so that it returns the id of the
`FunctionSystem`/`ExclusiveFunctionSystem` wrapper, but it did not
change `SystemTypeSet::system_type`, so doing the lookup breaks in
`bevy_mod_debugdump`.
## Solution
Change `IntoSystemSet` for functions to return a
`SystemTypeSet<FunctionSystem>` /
`SystemTypeSet<ExclusiveFunctionSystem>` instead of `SystemTypeSet<F>`.
Fixes#12016.
Bump version after release
This PR has been auto-generated
Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François <mockersf@gmail.com>
# Objective
We deprecated quite a few APIs in 0.13. 0.13 has shipped already. It
should be OK to remove them in 0.14's release. Fixes#4059. Fixes#9011.
## Solution
Remove them.
# Objective
* Fixes#11932 (performance impact when stepping is disabled)
## Solution
The `Option<FixedBitSet>` argument added to `ScheduleExecutor::run()` in
#8453 caused a measurable performance impact even when stepping is
disabled. This can be seen by the benchmark of running `Schedule:run()`
on an empty schedule in a tight loop
(https://github.com/bevyengine/bevy/issues/11932#issuecomment-1950970236).
I was able to get the same performance results as on 0.12.1 by changing
the argument
`ScheduleExecutor::run()` from `Option<FixedBitSet>` to
`Option<&FixedBitSet>`. The down-side of this change is that
`Schedule::run()` now takes about 6% longer (3.7319 ms vs 3.9855ns) when
stepping is enabled
---
## Changelog
* Change `ScheduleExecutor::run()` `_skipped_systems` from
`Option<FixedBitSet>` to `Option<&FixedBitSet>`
* Added a few benchmarks to measure `Schedule::run()` performance with
various executors
# Objective
There's a repeating pattern of `ThreadLocal<Cell<Vec<T>>>` which is very
useful for low overhead, low contention multithreaded queues that have
cropped up in a few places in the engine. This pattern is surprisingly
useful when building deferred mutation across multiple threads, as noted
by it's use in `ParallelCommands`.
However, `ThreadLocal<Cell<Vec<T>>>` is not only a mouthful, it's also
hard to ensure the thread-local queue is replaced after it's been
temporarily removed from the `Cell`.
## Solution
Wrap the pattern into `bevy_utils::Parallel<T>` which codifies the
entire pattern and ensures the user follows the contract. Instead of
fetching indivdual cells, removing the value, mutating it, and replacing
it, `Parallel::get` returns a `ParRef<'a, T>` which contains the
temporarily removed value and a reference back to the cell, and will
write the mutated value back to the cell upon being dropped.
I would like to use this to simplify the remaining part of #4899 that
has not been adopted/merged.
---
## Changelog
TODO
---------
Co-authored-by: Joseph <21144246+JoJoJet@users.noreply.github.com>
# Objective
`update_archetype_component_access` was removed from queries in #9774,
but some documentation still refers to it.
## Solution
Update the documentation. Since a bunch of these were in SAFETY comments
it would be nice if someone who knows the details better could check
that the rest of those comments are still valid.
# Objective
- There are multiple instances of `let Some(x) = ... else { None };`
throughout the project.
- Because `Option<T>` implements
[`Try`](https://doc.rust-lang.org/stable/std/ops/trait.Try.html), it can
use the question mark `?` operator.
## Solution
- Use question mark operator instead of `let Some(x) = ... else { None
}`.
---
There was another PR that did a similar thing a few weeks ago, but I
couldn't find it.
