# 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.
Use `TypeIdMap<T>` instead of `HashMap<TypeId, T>`
- ~~`TypeIdMap` was in `bevy_ecs`. I've kept it there because of
#11478~~
- ~~I haven't swapped `bevy_reflect` over because it doesn't depend on
`bevy_ecs`, but I'd also be happy with moving `TypeIdMap` to
`bevy_utils` and then adding a dependency to that~~
- ~~this is a slight change in the public API of
`DrawFunctionsInternal`, does this need to go in the changelog?~~
## Changelog
- moved `TypeIdMap` to `bevy_utils`
- changed `DrawFunctionsInternal::indices` to `TypeIdMap`
## Migration Guide
- `TypeIdMap` now lives in `bevy_utils`
- `DrawFunctionsInternal::indices` now uses a `TypeIdMap`.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Currently the `missing_docs` lint is allowed-by-default and enabled at
crate level when their documentations is complete (see #3492).
This PR proposes to inverse this logic by making `missing_docs`
warn-by-default and mark crates with imcomplete docs allowed.
## Solution
Makes `missing_docs` warn at workspace level and allowed at crate level
when the docs is imcomplete.
# Objective
My motivation are to resolve some of the issues I describe in this
[PR](https://github.com/bevyengine/bevy/issues/11415):
- not being able to easily mapping entities because the current
EntityMapper requires `&mut World` access
- not being able to create my own `EntityMapper` because some components
(`Parent` or `Children`) do not provide any public way of modifying the
inner entities
This PR makes the `MapEntities` trait accept a generic type that
implements `Mapper` to perform the mapping.
This means we don't need to use `EntityMapper` to perform our mapping,
we can use any type that implements `Mapper`. Basically this change is
very similar to what `serde` does. Instead of specifying directly how to
map entities for a given type, we have 2 distinct steps:
- the user implements `MapEntities` to define how the type will be
traversed and which `Entity`s will be mapped
- the `Mapper` defines how the mapping is actually done
This is similar to the distinction between `Serialize` (`MapEntities`)
and `Serializer` (`Mapper`).
This allows networking library to map entities without having to use the
existing `EntityMapper` (which requires `&mut World` access and the use
of `world_scope()`)
## Migration Guide
- The existing `EntityMapper` (notably used to replicate `Scenes` across
different `World`s) has been renamed to `SceneEntityMapper`
- The `MapEntities` trait now works with a generic `EntityMapper`
instead of the specific struct `EntityMapper`.
Calls to `fn map_entities(&mut self, entity_mapper: &mut EntityMapper)`
need to be updated to
`fn map_entities<M: EntityMapper>(&mut self, entity_mapper: &mut M)`
- The new trait `EntityMapper` has been added to the prelude
---------
Co-authored-by: Charles Bournhonesque <cbournhonesque@snapchat.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: UkoeHB <37489173+UkoeHB@users.noreply.github.com>
# Objective
- `FromType<T>` for `ReflectComponent` and `ReflectBundle` currently
require `T: FromWorld` for two reasons:
- they include a `from_world` method;
- they create dummy `T`s using `FromWorld` and then `apply` a `&dyn
Reflect` to it to simulate `FromReflect`.
- However `FromWorld`/`Default` may be difficult/weird/impractical to
implement, while `FromReflect` is easier and also more natural for the
job.
- See also
https://discord.com/channels/691052431525675048/1146022009554337792
## Solution
- Split `from_world` from `ReflectComponent` and `ReflectBundle` into
its own `ReflectFromWorld` struct.
- Replace the requirement on `FromWorld` in `ReflectComponent` and
`ReflectBundle` with `FromReflect`
---
## Changelog
- `ReflectComponent` and `ReflectBundle` no longer offer a `from_world`
method.
- `ReflectComponent` and `ReflectBundle`'s `FromType<T>` implementation
no longer requires `T: FromWorld`, but now requires `FromReflect`.
- `ReflectComponent::insert`, `ReflectComponent::apply_or_insert` and
`ReflectComponent::copy` now take an extra `&TypeRegistry` parameter.
- There is now a new `ReflectFromWorld` struct.
## Migration Guide
- Existing uses of `ReflectComponent::from_world` and
`ReflectBundle::from_world` will have to be changed to
`ReflectFromWorld::from_world`.
- Users of `#[reflect(Component)]` and `#[reflect(Bundle)]` will need to
also implement/derive `FromReflect`.
- Users of `#[reflect(Component)]` and `#[reflect(Bundle)]` may now want
to also add `FromWorld` to the list of reflected traits in case their
`FromReflect` implementation may fail.
- Users of `ReflectComponent` will now need to pass a `&TypeRegistry` to
its `insert`, `apply_or_insert` and `copy` methods.
# Objective
Expand the existing `Query` API to support more dynamic use cases i.e.
scripting.
## Prior Art
- #6390
- #8308
- #10037
## Solution
- Create a `QueryBuilder` with runtime methods to define the set of
component accesses for a built query.
- Create new `WorldQueryData` implementations `FilteredEntityMut` and
`FilteredEntityRef` as variants of `EntityMut` and `EntityRef` that
provide run time checked access to the components included in a given
query.
- Add new methods to `Query` to create "query lens" with a subset of the
access of the initial query.
### Query Builder
The `QueryBuilder` API allows you to define a query at runtime. At it's
most basic use it will simply create a query with the corresponding type
signature:
```rust
let query = QueryBuilder::<Entity, With<A>>::new(&mut world).build();
// is equivalent to
let query = QueryState::<Entity, With<A>>::new(&mut world);
```
Before calling `.build()` you also have the opportunity to add
additional accesses and filters. Here is a simple example where we add
additional filter terms:
```rust
let entity_a = world.spawn((A(0), B(0))).id();
let entity_b = world.spawn((A(0), C(0))).id();
let mut query_a = QueryBuilder::<Entity>::new(&mut world)
.with::<A>()
.without::<C>()
.build();
assert_eq!(entity_a, query_a.single(&world));
```
This alone is useful in that allows you to decide which archetypes your
query will match at runtime. However it is also very limited, consider a
case like the following:
```rust
let query_a = QueryBuilder::<&A>::new(&mut world)
// Add an additional access
.data::<&B>()
.build();
```
This will grant the query an additional read access to component B
however we have no way of accessing the data while iterating as the type
signature still only includes &A. For an even more concrete example of
this consider dynamic components:
```rust
let query_a = QueryBuilder::<Entity>::new(&mut world)
// Adding a filter is easy since it doesn't need be read later
.with_id(component_id_a)
// How do I access the data of this component?
.ref_id(component_id_b)
.build();
```
With this in mind the `QueryBuilder` API seems somewhat incomplete by
itself, we need some way method of accessing the components dynamically.
So here's one:
### Query Transmutation
If the problem is not having the component in the type signature why not
just add it? This PR also adds transmute methods to `QueryBuilder` and
`QueryState`. Here's a simple example:
```rust
world.spawn(A(0));
world.spawn((A(1), B(0)));
let mut query = QueryBuilder::<()>::new(&mut world)
.with::<B>()
.transmute::<&A>()
.build();
query.iter(&world).for_each(|a| assert_eq!(a.0, 1));
```
The `QueryState` and `QueryBuilder` transmute methods look quite similar
but are different in one respect. Transmuting a builder will always
succeed as it will just add the additional accesses needed for the new
terms if they weren't already included. Transmuting a `QueryState` will
panic in the case that the new type signature would give it access it
didn't already have, for example:
```rust
let query = QueryState::<&A, Option<&B>>::new(&mut world);
/// This is fine, the access for Option<&A> is less restrictive than &A
query.transmute::<Option<&A>>(&world);
/// Oh no, this would allow access to &B on entities that might not have it, so it panics
query.transmute::<&B>(&world);
/// This is right out
query.transmute::<&C>(&world);
```
This is quite an appealing API to also have available on `Query` however
it does pose one additional wrinkle: In order to to change the iterator
we need to create a new `QueryState` to back it. `Query` doesn't own
it's own state though, it just borrows it, so we need a place to borrow
it from. This is why `QueryLens` exists, it is a place to store the new
state so it can be borrowed when you call `.query()` leaving you with an
API like this:
```rust
fn function_that_takes_a_query(query: &Query<&A>) {
// ...
}
fn system(query: Query<(&A, &B)>) {
let lens = query.transmute_lens::<&A>();
let q = lens.query();
function_that_takes_a_query(&q);
}
```
Now you may be thinking: Hey, wait a second, you introduced the problem
with dynamic components and then described a solution that only works
for static components! Ok, you got me, I guess we need a bit more:
### Filtered Entity References
Currently the only way you can access dynamic components on entities
through a query is with either `EntityMut` or `EntityRef`, however these
can access all components and so conflict with all other accesses. This
PR introduces `FilteredEntityMut` and `FilteredEntityRef` as
alternatives that have additional runtime checking to prevent accessing
components that you shouldn't. This way you can build a query with a
`QueryBuilder` and actually access the components you asked for:
```rust
let mut query = QueryBuilder::<FilteredEntityRef>::new(&mut world)
.ref_id(component_id_a)
.with(component_id_b)
.build();
let entity_ref = query.single(&world);
// Returns Some(Ptr) as we have that component and are allowed to read it
let a = entity_ref.get_by_id(component_id_a);
// Will return None even though the entity does have the component, as we are not allowed to read it
let b = entity_ref.get_by_id(component_id_b);
```
For the most part these new structs have the exact same methods as their
non-filtered equivalents.
Putting all of this together we can do some truly dynamic ECS queries,
check out the `dynamic` example to see it in action:
```
Commands:
comp, c Create new components
spawn, s Spawn entities
query, q Query for entities
Enter a command with no parameters for usage.
> c A, B, C, Data 4
Component A created with id: 0
Component B created with id: 1
Component C created with id: 2
Component Data created with id: 3
> s A, B, Data 1
Entity spawned with id: 0v0
> s A, C, Data 0
Entity spawned with id: 1v0
> q &Data
0v0: Data: [1, 0, 0, 0]
1v0: Data: [0, 0, 0, 0]
> q B, &mut Data
0v0: Data: [2, 1, 1, 1]
> q B || C, &Data
0v0: Data: [2, 1, 1, 1]
1v0: Data: [0, 0, 0, 0]
```
## Changelog
- Add new `transmute_lens` methods to `Query`.
- Add new types `QueryBuilder`, `FilteredEntityMut`, `FilteredEntityRef`
and `QueryLens`
- `update_archetype_component_access` has been removed, archetype
component accesses are now determined by the accesses set in
`update_component_access`
- Added method `set_access` to `WorldQuery`, this is called before
`update_component_access` for queries that have a restricted set of
accesses, such as those built by `QueryBuilder` or `QueryLens`. This is
primarily used by the `FilteredEntity*` variants and has an empty trait
implementation.
- Added method `get_state` to `WorldQuery` as a fallible version of
`init_state` when you don't have `&mut World` access.
## Future Work
Improve performance of `FilteredEntityMut` and `FilteredEntityRef`,
currently they have to determine the accesses a query has in a given
archetype during iteration which is far from ideal, especially since we
already did the work when matching the archetype in the first place. To
avoid making more internal API changes I have left it out of this PR.
---------
Co-authored-by: Mike Hsu <mike.hsu@gmail.com>
Based on discussion after #11268 was merged:
Instead of panicking should the impl of `TypeId::hash` change
significantly, have a fallback and detect this in a test.
# Objective
`TypeId` contains a high-quality hash. Whenever a lookup based on a
`TypeId` is performed (e.g. to insert/remove components), the hash is
run through a second hash function. This is unnecessary.
## Solution
Skip re-hashing `TypeId`s.
In my
[testing](https://gist.github.com/SpecificProtagonist/4b49ad74c6b82b0aedd3b4ea35121be8),
this improves lookup performance consistently by 10%-15% (of course, the
lookup is only a small part of e.g. a bundle insertion).
# Objective
The purpose of this PR is to begin putting together a unified identifier
structure that can be used by entities and later components (as
entities) as well as relationship pairs for relations, to enable all of
these to be able to use the same storages. For the moment, to keep
things small and focused, only `Entity` is being changed to make use of
the new `Identifier` type, keeping `Entity`'s API and
serialization/deserialization the same. Further changes are for
follow-up PRs.
## Solution
`Identifier` is a wrapper around `u64` split into two `u32` segments
with the idea of being generalised to not impose restrictions on
variants. That is for `Entity` to do. Instead, it is a general API for
taking bits to then merge and map into a `u64` integer. It exposes
low/high methods to return the two value portions as `u32` integers,
with then the MSB masked for usage as a type flag, enabling entity kind
discrimination and future activation/deactivation semantics.
The layout in this PR for `Identifier` is described as below, going from
MSB -> LSB.
```
|F| High value | Low value |
|_|_______________________________|________________________________|
|1| 31 | 32 |
F = Bit Flags
```
The high component in this implementation has only 31 bits, but that
still leaves 2^31 or 2,147,483,648 values that can be stored still, more
than enough for any generation/relation kinds/etc usage. The low part is
a full 32-bit index. The flags allow for 1 bit to be used for
entity/pair discrimination, as these have different usages for the
low/high portions of the `Identifier`. More bits can be reserved for
more variants or activation/deactivation purposes, but this currently
has no use in bevy.
More bits could be reserved for future features at the cost of bits for
the high component, so how much to reserve is up for discussion. Also,
naming of the struct and methods are also subject to further
bikeshedding and feedback.
Also, because IDs can have different variants, I wonder if
`Entity::from_bits` needs to return a `Result` instead of potentially
panicking on receiving an invalid ID.
PR is provided as an early WIP to obtain feedback and notes on whether
this approach is viable.
---
## Changelog
### Added
New `Identifier` struct for unifying IDs.
### Changed
`Entity` changed to use new `Identifier`/`IdentifierMask` as the
underlying ID logic.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: vero <email@atlasdostal.com>
# Objective
- Implements change described in
https://github.com/bevyengine/bevy/issues/3022
- Goal is to allow Entity to benefit from niche optimization, especially
in the case of Option<Entity> to reduce memory overhead with structures
with empty slots
## Discussion
- First PR attempt: https://github.com/bevyengine/bevy/pull/3029
- Discord:
https://discord.com/channels/691052431525675048/1154573759752183808/1154573764240093224
## Solution
- Change `Entity::generation` from u32 to NonZeroU32 to allow for niche
optimization.
- The reason for changing generation rather than index is so that the
costs are only encountered on Entity free, instead of on Entity alloc
- There was some concern with generations being used, due to there being
some desire to introduce flags. This was more to do with the original
retirement approach, however, in reality even if generations were
reduced to 24-bits, we would still have 16 million generations available
before wrapping and current ideas indicate that we would be using closer
to 4-bits for flags.
- Additionally, another concern was the representation of relationships
where NonZeroU32 prevents us using the full address space, talking with
Joy it seems unlikely to be an issue. The majority of the time these
entity references will be low-index entries (ie. `ChildOf`, `Owes`),
these will be able to be fast lookups, and the remainder of the range
can use slower lookups to map to the address space.
- It has the additional benefit of being less visible to most users,
since generation is only ever really set through `from_bits` type
methods.
- `EntityMeta` was changed to match
- On free, generation now explicitly wraps:
- Originally, generation would panic in debug mode and wrap in release
mode due to using regular ops.
- The first attempt at this PR changed the behavior to "retire" slots
and remove them from use when generations overflowed. This change was
controversial, and likely needs a proper RFC/discussion.
- Wrapping matches current release behaviour, and should therefore be
less controversial.
- Wrapping also more easily migrates to the retirement approach, as
users likely to exhaust the exorbitant supply of generations will code
defensively against aliasing and that defensive code is less likely to
break than code assuming that generations don't wrap.
- We use some unsafe code here when wrapping generations, to avoid
branch on NonZeroU32 construction. It's guaranteed safe due to how we
perform wrapping and it results in significantly smaller ASM code.
- https://godbolt.org/z/6b6hj8PrM
## Migration
- Previous `bevy_scene` serializations have a high likelihood of being
broken, as they contain 0th generation entities.
## Current Issues
- `Entities::reserve_generations` and `EntityMapper` wrap now, even in
debug - although they technically did in release mode already so this
probably isn't a huge issue. It just depends if we need to change
anything here?
---------
Co-authored-by: Natalie Baker <natalie.baker@advancednavigation.com>
# Objective
- Make it possible to react to arbitrary state changes
- this will be useful regardless of the other changes to states
currently being discussed
## Solution
- added `StateTransitionEvent<S>` struct
- previously, this would have been impossible:
```rs
#[derive(States, Eq, PartialEq, Hash, Copy, Clone, Default)]
enum MyState {
#[default]
Foo,
Bar(MySubState),
}
enum MySubState {
Spam,
Eggs,
}
app.add_system(Update, on_enter_bar);
fn on_enter_bar(trans: EventReader<StateTransition<MyState>>){
for (befoare, after) in trans.read() {
match before, after {
MyState::Foo, MyState::Bar(_) => info!("detected transition foo => bar");
_, _ => ();
}
}
}
```
---
## Changelog
- Added
- `StateTransitionEvent<S>` - Fired on state changes of `S`
## Migration Guide
N/A no breaking changes
---------
Co-authored-by: Federico Rinaldi <gisquerin@gmail.com>
# Objective
After #6547, `Query::for_each` has been capable of automatic
vectorization on certain queries, which is seeing a notable (>50% CPU
time improvements) for iteration. However, `Query::for_each` isn't
idiomatic Rust, and lacks the flexibility of iterator combinators.
Ideally, `Query::iter` and friends should be able to achieve the same
results. However, this does seem to blocked upstream
(rust-lang/rust#104914) by Rust's loop optimizations.
## Solution
This is an intermediate solution and refactor. This moves the
`Query::for_each` implementation onto the `Iterator::fold`
implementation for `QueryIter` instead. This should result in the same
automatic vectorization optimization on all `Iterator` functions that
internally use fold, including `Iterator::for_each`, `Iterator::count`,
etc.
With this, it should close the gap between the two completely.
Internally, this PR changes `Query::for_each` to use
`query.iter().for_each(..)` instead of the duplicated implementation.
Separately, the duplicate implementations of internal iteration (i.e.
`Query::par_for_each`) now use portions of the current `Query::for_each`
implementation factored out into their own functions.
This also massively cleans up our internal fragmentation of internal
iteration options, deduplicating the iteration code used in `for_each`
and `par_iter().for_each()`.
---
## Changelog
Changed: `Query::for_each`, `Query::for_each_mut`, `Query::for_each`,
and `Query::for_each_mut` have been moved to `QueryIter`'s
`Iterator::for_each` implementation, and still retains their performance
improvements over normal iteration. These APIs are deprecated in 0.13
and will be removed in 0.14.
---------
Co-authored-by: JoJoJet <21144246+JoJoJet@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Fixes#7680
- This is an updated for https://github.com/bevyengine/bevy/pull/8899
which had the same objective but fell a long way behind the latest
changes
## Solution
The traits `WorldQueryData : WorldQuery` and `WorldQueryFilter :
WorldQuery` have been added and some of the types and functions from
`WorldQuery` has been moved into them.
`ReadOnlyWorldQuery` has been replaced with `ReadOnlyWorldQueryData`.
`WorldQueryFilter` is safe (as long as `WorldQuery` is implemented
safely).
`WorldQueryData` is unsafe - safely implementing it requires that
`Self::ReadOnly` is a readonly version of `Self` (this used to be a
safety requirement of `WorldQuery`)
The type parameters `Q` and `F` of `Query` must now implement
`WorldQueryData` and `WorldQueryFilter` respectively.
This makes it impossible to accidentally use a filter in the data
position or vice versa which was something that could lead to bugs.
~~Compile failure tests have been added to check this.~~
It was previously sometimes useful to use `Option<With<T>>` in the data
position. Use `Has<T>` instead in these cases.
The `WorldQuery` derive macro has been split into separate derive macros
for `WorldQueryData` and `WorldQueryFilter`.
Previously it was possible to derive both `WorldQuery` for a struct that
had a mixture of data and filter items. This would not work correctly in
some cases but could be a useful pattern in others. *This is no longer
possible.*
---
## Notes
- The changes outside of `bevy_ecs` are all changing type parameters to
the new types, updating the macro use, or replacing `Option<With<T>>`
with `Has<T>`.
- All `WorldQueryData` types always returned `true` for `IS_ARCHETYPAL`
so I moved it to `WorldQueryFilter` and
replaced all calls to it with `true`. That should be the only logic
change outside of the macro generation code.
- `Changed<T>` and `Added<T>` were being generated by a macro that I
have expanded. Happy to revert that if desired.
- The two derive macros share some functions for implementing
`WorldQuery` but the tidiest way I could find to implement them was to
give them a ton of arguments and ask clippy to ignore that.
## Changelog
### Changed
- Split `WorldQuery` into `WorldQueryData` and `WorldQueryFilter` which
now have separate derive macros. It is not possible to derive both for
the same type.
- `Query` now requires that the first type argument implements
`WorldQueryData` and the second implements `WorldQueryFilter`
## Migration Guide
- Update derives
```rust
// old
#[derive(WorldQuery)]
#[world_query(mutable, derive(Debug))]
struct CustomQuery {
entity: Entity,
a: &'static mut ComponentA
}
#[derive(WorldQuery)]
struct QueryFilter {
_c: With<ComponentC>
}
// new
#[derive(WorldQueryData)]
#[world_query_data(mutable, derive(Debug))]
struct CustomQuery {
entity: Entity,
a: &'static mut ComponentA,
}
#[derive(WorldQueryFilter)]
struct QueryFilter {
_c: With<ComponentC>
}
```
- Replace `Option<With<T>>` with `Has<T>`
```rust
/// old
fn my_system(query: Query<(Entity, Option<With<ComponentA>>)>)
{
for (entity, has_a_option) in query.iter(){
let has_a:bool = has_a_option.is_some();
//todo!()
}
}
/// new
fn my_system(query: Query<(Entity, Has<ComponentA>)>)
{
for (entity, has_a) in query.iter(){
//todo!()
}
}
```
- Fix queries which had filters in the data position or vice versa.
```rust
// old
fn my_system(query: Query<(Entity, With<ComponentA>)>)
{
for (entity, _) in query.iter(){
//todo!()
}
}
// new
fn my_system(query: Query<Entity, With<ComponentA>>)
{
for entity in query.iter(){
//todo!()
}
}
// old
fn my_system(query: Query<AnyOf<(&ComponentA, With<ComponentB>)>>)
{
for (entity, _) in query.iter(){
//todo!()
}
}
// new
fn my_system(query: Query<Option<&ComponentA>, Or<(With<ComponentA>, With<ComponentB>)>>)
{
for entity in query.iter(){
//todo!()
}
}
```
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Enables warning on `clippy::undocumented_unsafe_blocks` across the
workspace rather than only in `bevy_ecs`, `bevy_transform` and
`bevy_utils`. This adds a little awkwardness in a few areas of code that
have trivial safety or explain safety for multiple unsafe blocks with
one comment however automatically prevents these comments from being
missed.
## Solution
This adds `undocumented_unsafe_blocks = "warn"` to the workspace
`Cargo.toml` and fixes / adds a few missed safety comments. I also added
`#[allow(clippy::undocumented_unsafe_blocks)]` where the safety is
explained somewhere above.
There are a couple of safety comments I added I'm not 100% sure about in
`bevy_animation` and `bevy_render/src/view` and I'm not sure about the
use of `#[allow(clippy::undocumented_unsafe_blocks)]` compared to adding
comments like `// SAFETY: See above`.
# Objective
- Fix adding `#![allow(clippy::type_complexity)]` everywhere. like #9796
## Solution
- Use the new [lints] table that will land in 1.74
(https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#lints)
- inherit lint to the workspace, crates and examples.
```
[lints]
workspace = true
```
## Changelog
- Bump rust version to 1.74
- Enable lints table for the workspace
```toml
[workspace.lints.clippy]
type_complexity = "allow"
```
- Allow type complexity for all crates and examples
```toml
[lints]
workspace = true
```
---------
Co-authored-by: Martín Maita <47983254+mnmaita@users.noreply.github.com>
# Objective
Reduce code duplication and improve APIs of Bevy's [global
taskpools](https://github.com/bevyengine/bevy/blob/main/crates/bevy_tasks/src/usages.rs).
## Solution
- As all three of the global taskpools have identical implementations
and only differ in their identifiers, this PR moves the implementation
into a macro to reduce code duplication.
- The `init` method is renamed to `get_or_init` to more accurately
reflect what it really does.
- Add a new `try_get` method that just returns `None` when the pool is
uninitialized, to complement the other getter methods.
- Minor documentation improvements to accompany the above changes.
---
## Changelog
- Added a new `try_get` method to the global TaskPools
- The global TaskPools' `init` method has been renamed to `get_or_init`
for clarity
- Documentation improvements
## Migration Guide
- Uses of `ComputeTaskPool::init`, `AsyncComputeTaskPool::init` and
`IoTaskPool::init` should be changed to `::get_or_init`.
# Objective
- Fixes#9244.
## Solution
- Changed the `(Into)SystemSetConfigs` traits and structs be more like
the `(Into)SystemConfigs` traits and structs.
- Replaced uses of `IntoSystemSetConfig` with `IntoSystemSetConfigs`
- Added generic `ItemConfig` and `ItemConfigs` types.
- Changed `SystemConfig(s)` and `SystemSetConfig(s)` to be type aliases
to `ItemConfig(s)`.
- Added generic `process_configs` to `ScheduleGraph`.
- Changed `configure_sets_inner` and `add_systems_inner` to reuse
`process_configs`.
---
## Changelog
- Added `run_if` to `IntoSystemSetConfigs`
- Deprecated `Schedule::configure_set` and `App::configure_set`
- Removed `IntoSystemSetConfig`
## Migration Guide
- Use `App::configure_sets` instead of `App::configure_set`
- Use `Schedule::configure_sets` instead of `Schedule::configure_set`
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Fix#4278Fix#5504Fix#9422
Provide safe ways to borrow an entire entity, while allowing disjoint
mutable access. `EntityRef` and `EntityMut` are not suitable for this,
since they provide access to the entire world -- they are just helper
types for working with `&World`/`&mut World`.
This has potential uses for reflection and serialization
## Solution
Remove `EntityRef::world`, which allows it to soundly be used within
queries.
`EntityMut` no longer supports structural world mutations, which allows
multiple instances of it to exist for different entities at once.
Structural world mutations are performed using the new type
`EntityWorldMut`.
```rust
fn disjoint_system(
q2: Query<&mut A>,
q1: Query<EntityMut, Without<A>>,
) { ... }
let [entity1, entity2] = world.many_entities_mut([id1, id2]);
*entity1.get_mut::<T>().unwrap() = *entity2.get().unwrap();
for entity in world.iter_entities_mut() {
...
}
```
---
## Changelog
- Removed `EntityRef::world`, to fix a soundness issue with queries.
+ Removed the ability to structurally mutate the world using
`EntityMut`, which allows it to be used in queries.
+ Added `EntityWorldMut`, which is used to perform structural mutations
that are no longer allowed using `EntityMut`.
## Migration Guide
**Note for maintainers: ensure that the guide for #9604 is updated
accordingly.**
Removed the method `EntityRef::world`, to fix a soundness issue with
queries. If you need access to `&World` while using an `EntityRef`,
consider passing the world as a separate parameter.
`EntityMut` can no longer perform 'structural' world mutations, such as
adding or removing components, or despawning the entity. Additionally,
`EntityMut::world`, `EntityMut::world_mut` , and
`EntityMut::world_scope` have been removed.
Instead, use the newly-added type `EntityWorldMut`, which is a helper
type for working with `&mut World`.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Any time we wish to transform the output of a system, we currently use
system piping to do so:
```rust
my_system.pipe(|In(x)| do_something(x))
```
Unfortunately, system piping is not a zero cost abstraction. Each call
to `.pipe` requires allocating two extra access sets: one for the second
system and one for the combined accesses of both systems. This also adds
extra work to each call to `update_archetype_component_access`, which
stacks as one adds multiple layers of system piping.
## Solution
Add the `AdapterSystem` abstraction: similar to `CombinatorSystem`, this
allows you to implement a trait to generically control how a system is
run and how its inputs and outputs are processed. Unlike
`CombinatorSystem`, this does not have any overhead when computing world
accesses which makes it ideal for simple operations such as inverting or
ignoring the output of a system.
Add the extension method `.map(...)`: this is similar to `.pipe(...)`,
only it accepts a closure as an argument instead of an `In<T>` system.
```rust
my_system.map(do_something)
```
This has the added benefit of making system names less messy: a system
that ignores its output will just be called `my_system`, instead of
`Pipe(my_system, ignore)`
---
## Changelog
TODO
## Migration Guide
The `system_adapter` functions have been deprecated: use `.map` instead,
which is a lightweight alternative to `.pipe`.
```rust
// Before:
my_system.pipe(system_adapter::ignore)
my_system.pipe(system_adapter::unwrap)
my_system.pipe(system_adapter::new(T::from))
// After:
my_system.map(std::mem::drop)
my_system.map(Result::unwrap)
my_system.map(T::from)
// Before:
my_system.pipe(system_adapter::info)
my_system.pipe(system_adapter::dbg)
my_system.pipe(system_adapter::warn)
my_system.pipe(system_adapter::error)
// After:
my_system.map(bevy_utils::info)
my_system.map(bevy_utils::dbg)
my_system.map(bevy_utils::warn)
my_system.map(bevy_utils::error)
```
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Partially address #5504. Fix#4278. Provide "whole entity" access in
queries. This can be useful when you don't know at compile time what
you're accessing (i.e. reflection via `ReflectComponent`).
## Solution
Implement `WorldQuery` for `EntityRef`.
- This provides read-only access to the entire entity, and supports
anything that `EntityRef` can normally do.
- It matches all archetypes and tables and will densely iterate when
possible.
- It marks all of the ArchetypeComponentIds of a matched archetype as
read.
- Adding it to a query will cause it to panic if used in conjunction
with any other mutable access.
- Expanded the docs on Query to advertise this feature.
- Added tests to ensure the panics were working as intended.
- Added `EntityRef` to the ECS prelude.
To make this safe, `EntityRef::world` was removed as it gave potential
`UnsafeCell`-like access to other parts of the `World` including aliased
mutable access to the components it would otherwise read safely.
## Performance
Not great beyond the additional parallelization opportunity over
exclusive systems. The `EntityRef` is fetched from `Entities` like any
other call to `World::entity`, which can be very random access heavy.
This could be simplified if `ArchetypeRow` is available in
`WorldQuery::fetch`'s arguments, but that's likely not something we
should optimize for.
## Future work
An equivalent API where it gives mutable access to all components on a
entity can be done with a scoped version of `EntityMut` where it does
not provide `&mut World` access nor allow for structural changes to the
entity is feasible as well. This could be done as a safe alternative to
exclusive system when structural mutation isn't required or the target
set of entities is scoped.
---
## Changelog
Added: `Access::has_any_write`
Added: `EntityRef` now implements `WorldQuery`. Allows read-only access
to the entire entity, incompatible with any other mutable access, can be
mixed with `With`/`Without` filters for more targeted use.
Added: `EntityRef` to `bevy::ecs::prelude`.
Removed: `EntityRef::world`
## Migration Guide
TODO
---------
Co-authored-by: Carter Weinberg <weinbergcarter@gmail.com>
Co-authored-by: Jakob Hellermann <jakob.hellermann@protonmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Use `AppTypeRegistry` on API defined in `bevy_ecs`
(https://github.com/bevyengine/bevy/pull/8895#discussion_r1234748418)
A lot of the API on `Reflect` depends on a registry. When it comes to
the ECS. We should use `AppTypeRegistry` in the general case.
This is however impossible in `bevy_ecs`, since `AppTypeRegistry` is
defined in `bevy_app`.
## Solution
- Move `AppTypeRegistry` resource definition from `bevy_app` to
`bevy_ecs`
- Still add the resource in the `App` plugin, since bevy_ecs itself
doesn't know of plugins
Note that `bevy_ecs` is a dependency of `bevy_app`, so nothing
revolutionary happens.
## Alternative
- Define the API as a trait in `bevy_app` over `bevy_ecs`. (though this
prevents us from using bevy_ecs internals)
- Do not rely on `AppTypeRegistry` for the API in question, requring
users to extract themselves the resource and pass it to the API methods.
---
## Changelog
- Moved `AppTypeRegistry` resource definition from `bevy_app` to
`bevy_ecs`
## Migration Guide
- If you were **not** using a `prelude::*` to import `AppTypeRegistry`,
you should update your imports:
```diff
- use bevy::app::AppTypeRegistry;
+ use bevy::ecs::reflect::AppTypeRegistry
```
# Objective
Resolves#7558.
Systems that are known to never modify the world implement the trait
`ReadOnlySystem`. This is a perfect place to add a safe API for running
a system with a shared reference to a World.
---
## Changelog
- Added the trait method `ReadOnlySystem::run_readonly`, which allows a
system to be run using `&World`.
# Objective
Title.
---------
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: James Liu <contact@jamessliu.com>
# Objective
- `apply_system_buffers` is an unhelpful name: it introduces a new
internal-only concept
- this is particularly rough for beginners as reasoning about how
commands work is a critical stumbling block
## Solution
- rename `apply_system_buffers` to the more descriptive `apply_deferred`
- rename related fields, arguments and methods in the internals fo
bevy_ecs for consistency
- update the docs
## Changelog
`apply_system_buffers` has been renamed to `apply_deferred`, to more
clearly communicate its intent and relation to `Deferred` system
parameters like `Commands`.
## Migration Guide
- `apply_system_buffers` has been renamed to `apply_deferred`
- the `apply_system_buffers` method on the `System` trait has been
renamed to `apply_deferred`
- the `is_apply_system_buffers` function has been replaced by
`is_apply_deferred`
- `Executor::set_apply_final_buffers` is now
`Executor::set_apply_final_deferred`
- `Schedule::apply_system_buffers` is now `Schedule::apply_deferred`
---------
Co-authored-by: JoJoJet <21144246+JoJoJet@users.noreply.github.com>
Links in the api docs are nice. I noticed that there were several places
where structs / functions and other things were referenced in the docs,
but weren't linked. I added the links where possible / logical.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
# Objective
- Currently, it is not possible to call `.pipe` on a system that takes
any input other than `()`.
- The `IntoPipeSystem` trait is currently very difficult to parse due to
its use of generics.
## Solution
Remove the `IntoPipeSystem` trait, and move the `pipe` method to
`IntoSystem`.
---
## Changelog
- System piping has been made more flexible: it is now possible to call
`.pipe` on a system that takes an input.
## Migration Guide
The `IntoPipeSystem` trait has been removed, and the `pipe` method has
been moved to the `IntoSystem` trait.
```rust
// Before:
use bevy_ecs::system::IntoPipeSystem;
schedule.add_systems(first.pipe(second));
// After:
use bevy_ecs::system::IntoSystem;
schedule.add_systems(first.pipe(second));
```
# Objective
The clippy lint `type_complexity` is known not to play well with bevy.
It frequently triggers when writing complex queries, and taking the
lint's advice of using a type alias almost always just obfuscates the
code with no benefit. Because of this, this lint is currently ignored in
CI, but unfortunately it still shows up when viewing bevy code in an
IDE.
As someone who's made a fair amount of pull requests to this repo, I
will say that this issue has been a consistent thorn in my side. Since
bevy code is filled with spurious, ignorable warnings, it can be very
difficult to spot the *real* warnings that must be fixed -- most of the
time I just ignore all warnings, only to later find out that one of them
was real after I'm done when CI runs.
## Solution
Suppress this lint in all bevy crates. This was previously attempted in
#7050, but the review process ended up making it more complicated than
it needs to be and landed on a subpar solution.
The discussion in https://github.com/rust-lang/rust-clippy/pull/10571
explores some better long-term solutions to this problem. Since there is
no timeline on when these solutions may land, we should resolve this
issue in the meantime by locally suppressing these lints.
### Unresolved issues
Currently, these lints are not suppressed in our examples, since that
would require suppressing the lint in every single source file. They are
still ignored in CI.
# Objective
- A more intuitive distinction between the two. `remove_intersection` is verbose and unclear.
- `EntityMut::remove` and `Commands::remove` should match.
## Solution
- What the title says.
---
## Migration Guide
Before
```rust
fn clear_children(parent: Entity, world: &mut World) {
if let Some(children) = world.entity_mut(parent).remove::<Children>() {
for &child in &children.0 {
world.entity_mut(child).remove_intersection::<Parent>();
}
}
}
```
After
```rust
fn clear_children(parent: Entity, world: &mut World) {
if let Some(children) = world.entity_mut(parent).take::<Children>() {
for &child in &children.0 {
world.entity_mut(child).remove::<Parent>();
}
}
}
```
# Objective
Fix#7584.
## Solution
Add an abstraction for creating custom system combinators with minimal boilerplate. Use this to implement AND/OR combinators. Use this to simplify the implementation of `PipeSystem`.
## Example
Feel free to bikeshed on the syntax.
I chose the names `and_then`/`or_else` to emphasize the fact that these short-circuit, while I chose method syntax to empasize that the arguments are *not* treated equally.
```rust
app.add_systems((
my_system.run_if(resource_exists::<R>().and_then(resource_equals(R(0)))),
our_system.run_if(resource_exists::<R>().or_else(resource_exists::<S>())),
));
```
---
## Todo
- [ ] Decide on a syntax
- [x] Write docs
- [x] Write tests
## Changelog
+ Added the extension methods `.and_then(...)` and `.or_else(...)` to run conditions, which allows combining run conditions with short-circuiting behavior.
+ Added the trait `Combine`, which can be used with the new `CombinatorSystem` to create system combinators with custom behavior.
# Objective
`ChangeTrackers<>` is a `WorldQuery` type that lets you access the change ticks for a component. #7097 has added `Ref<>`, which gives access to a component's value in addition to its change ticks. Since bevy's access model does not separate a component's value from its change ticks, there is no benefit to using `ChangeTrackers<T>` over `Ref<T>`.
## Solution
Deprecate `ChangeTrackers<>`.
---
## Changelog
* `ChangeTrackers<T>` has been deprecated. It will be removed in Bevy 0.11.
## Migration Guide
`ChangeTrackers<T>` has been deprecated, and will be removed in the next release. Any usage should be replaced with `Ref<T>`.
```rust
// Before (0.9)
fn my_system(q: Query<(&MyComponent, ChangeTrackers<MyComponent>)>) {
for (value, trackers) in &q {
if trackers.is_changed() {
// Do something with `value`.
}
}
}
// After (0.10)
fn my_system(q: Query<Ref<MyComponent>>) {
for value in &q {
if value.is_changed() {
// Do something with `value`.
}
}
}
```
# Objective
- Fixes#5432
- Fixes#6680
## Solution
- move code responsible for generating the `impl TypeUuid` from `type_uuid_derive` into a new function, `gen_impl_type_uuid`.
- this allows the new proc macro, `impl_type_uuid`, to call the code for generation.
- added struct `TypeUuidDef` and implemented `syn::Parse` to allow parsing of the input for the new macro.
- finally, used the new macro `impl_type_uuid` to implement `TypeUuid` for the standard library (in `crates/bevy_reflect/src/type_uuid_impl.rs`).
- fixes#6680 by doing a wrapping add of the param's index to its `TYPE_UUID`
Co-authored-by: dis-da-moe <84386186+dis-da-moe@users.noreply.github.com>
…u64, so hash safety is not a concern
# Objective
- While reading the code, just noticed the BundleInfo's HashMap is std::collections::HashMap, which uses a slow but safe hasher.
## Solution
- Use bevy_utils::HashMap instead
benchmark diff (I run several times in a linux box, the perf improvement is consistent, though numbers varies from time to time, I paste my last run result here):
``` bash
cargo bench -- spawn
Compiling bevy_ecs v0.9.0 (/home/lishuo/developer/pr/bevy/crates/bevy_ecs)
Compiling bevy_app v0.9.0 (/home/lishuo/developer/pr/bevy/crates/bevy_app)
Compiling benches v0.1.0 (/home/lishuo/developer/pr/bevy/benches)
Finished bench [optimized] target(s) in 1m 17s
Running benches/bevy_ecs/change_detection.rs (/home/lishuo/developer/pr/bevy/benches/target/release/deps/change_detection-86c5445d0dc34529)
Gnuplot not found, using plotters backend
Running benches/bevy_ecs/benches.rs (/home/lishuo/developer/pr/bevy/benches/target/release/deps/ecs-e49b3abe80bfd8c0)
Gnuplot not found, using plotters backend
spawn_commands/2000_entities
time: [153.94 µs 159.19 µs 164.37 µs]
change: [-14.706% -11.050% -6.9633%] (p = 0.00 < 0.05)
Performance has improved.
spawn_commands/4000_entities
time: [328.77 µs 339.11 µs 349.11 µs]
change: [-7.6331% -3.9932% +0.0487%] (p = 0.06 > 0.05)
No change in performance detected.
spawn_commands/6000_entities
time: [445.01 µs 461.29 µs 477.36 µs]
change: [-16.639% -13.358% -10.006%] (p = 0.00 < 0.05)
Performance has improved.
spawn_commands/8000_entities
time: [657.94 µs 677.71 µs 696.95 µs]
change: [-8.8708% -5.2591% -1.6847%] (p = 0.01 < 0.05)
Performance has improved.
get_or_spawn/individual time: [452.02 µs 466.70 µs 482.07 µs]
change: [-17.218% -14.041% -10.728%] (p = 0.00 < 0.05)
Performance has improved.
get_or_spawn/batched time: [291.12 µs 301.12 µs 311.31 µs]
change: [-12.281% -8.9163% -5.3660%] (p = 0.00 < 0.05)
Performance has improved.
spawn_world/1_entities time: [81.668 ns 84.284 ns 86.860 ns]
change: [-12.251% -6.7872% -1.5402%] (p = 0.02 < 0.05)
Performance has improved.
spawn_world/10_entities time: [789.78 ns 821.96 ns 851.95 ns]
change: [-19.738% -14.186% -8.0733%] (p = 0.00 < 0.05)
Performance has improved.
spawn_world/100_entities
time: [7.9906 µs 8.2449 µs 8.5013 µs]
change: [-12.417% -6.6837% -0.8766%] (p = 0.02 < 0.05)
Change within noise threshold.
spawn_world/1000_entities
time: [81.602 µs 84.161 µs 86.833 µs]
change: [-13.656% -8.6520% -3.0491%] (p = 0.00 < 0.05)
Performance has improved.
Found 1 outliers among 100 measurements (1.00%)
1 (1.00%) high mild
Benchmarking spawn_world/10000_entities: Warming up for 500.00 ms
Warning: Unable to complete 100 samples in 4.0s. You may wish to increase target time to 4.0s, enable flat sampling, or reduce sample count to 70.
spawn_world/10000_entities
time: [813.02 µs 839.76 µs 865.41 µs]
change: [-12.133% -6.1970% -0.2302%] (p = 0.05 < 0.05)
Change within noise threshold.
```
---
## Changelog
> This section is optional. If this was a trivial fix, or has no externally-visible impact, you can delete this section.
- use bevy_utils::HashMap for Bundles::bundle_ids
## Migration Guide
> This section is optional. If there are no breaking changes, you can delete this section.
- Not a breaking change, hashmap is internal impl.
# Objective
One pattern to increase parallelism is deferred mutation: instead of directly mutating the world (and preventing other systems from running at the same time), you queue up operations to be applied to the world at the end of the stage. The most common example of this pattern uses the `Commands` SystemParam.
In order to avoid the overhead associated with commands, some power users may want to add their own deferred mutation behavior. To do this, you must implement the unsafe trait `SystemParam`, which interfaces with engine internals in a way that we'd like users to be able to avoid.
## Solution
Add the `Deferred<T>` primitive `SystemParam`, which encapsulates the deferred mutation pattern.
This can be combined with other types of `SystemParam` to safely and ergonomically create powerful custom types.
Essentially, this is just a variant of `Local<T>` which can run code at the end of the stage.
This type is used in the engine to derive `Commands` and `ParallelCommands`, which removes a bunch of unsafe boilerplate.
### Example
```rust
use bevy_ecs::system::{Deferred, SystemBuffer};
/// Sends events with a delay, but may run in parallel with other event writers.
#[derive(SystemParam)]
pub struct BufferedEventWriter<'s, E: Event> {
queue: Deferred<'s, EventQueue<E>>,
}
struct EventQueue<E>(Vec<E>);
impl<'s, E: Event> BufferedEventWriter<'s, E> {
/// Queues up an event to be sent at the end of this stage.
pub fn send(&mut self, event: E) {
self.queue.0.push(event);
}
}
// The `SystemBuffer` trait controls how [`Deferred`] gets applied at the end of the stage.
impl<E: Event> SystemBuffer for EventQueue<E> {
fn apply(&mut self, world: &mut World) {
let mut events = world.resource_mut::<Events<E>>();
for e in self.0.drain(..) {
events.send(e);
}
}
}
```
---
## Changelog
+ Added the `SystemParam` type `Deferred<T>`, which can be used to defer `World` mutations. Powered by the new trait `SystemBuffer`.
Huge thanks to @maniwani, @devil-ira, @hymm, @cart, @superdump and @jakobhellermann for the help with this PR.
# Objective
- Followup #6587.
- Minimal integration for the Stageless Scheduling RFC: https://github.com/bevyengine/rfcs/pull/45
## Solution
- [x] Remove old scheduling module
- [x] Migrate new methods to no longer use extension methods
- [x] Fix compiler errors
- [x] Fix benchmarks
- [x] Fix examples
- [x] Fix docs
- [x] Fix tests
## Changelog
### Added
- a large number of methods on `App` to work with schedules ergonomically
- the `CoreSchedule` enum
- `App::add_extract_system` via the `RenderingAppExtension` trait extension method
- the private `prepare_view_uniforms` system now has a public system set for scheduling purposes, called `ViewSet::PrepareUniforms`
### Removed
- stages, and all code that mentions stages
- states have been dramatically simplified, and no longer use a stack
- `RunCriteriaLabel`
- `AsSystemLabel` trait
- `on_hierarchy_reports_enabled` run criteria (now just uses an ad hoc resource checking run condition)
- systems in `RenderSet/Stage::Extract` no longer warn when they do not read data from the main world
- `RunCriteriaLabel`
- `transform_propagate_system_set`: this was a nonstandard pattern that didn't actually provide enough control. The systems are already `pub`: the docs have been updated to ensure that the third-party usage is clear.
### Changed
- `System::default_labels` is now `System::default_system_sets`.
- `App::add_default_labels` is now `App::add_default_sets`
- `CoreStage` and `StartupStage` enums are now `CoreSet` and `StartupSet`
- `App::add_system_set` was renamed to `App::add_systems`
- The `StartupSchedule` label is now defined as part of the `CoreSchedules` enum
- `.label(SystemLabel)` is now referred to as `.in_set(SystemSet)`
- `SystemLabel` trait was replaced by `SystemSet`
- `SystemTypeIdLabel<T>` was replaced by `SystemSetType<T>`
- The `ReportHierarchyIssue` resource now has a public constructor (`new`), and implements `PartialEq`
- Fixed time steps now use a schedule (`CoreSchedule::FixedTimeStep`) rather than a run criteria.
- Adding rendering extraction systems now panics rather than silently failing if no subapp with the `RenderApp` label is found.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied.
- `SceneSpawnerSystem` now runs under `CoreSet::Update`, rather than `CoreStage::PreUpdate.at_end()`.
- `bevy_pbr::add_clusters` is no longer an exclusive system
- the top level `bevy_ecs::schedule` module was replaced with `bevy_ecs::scheduling`
- `tick_global_task_pools_on_main_thread` is no longer run as an exclusive system. Instead, it has been replaced by `tick_global_task_pools`, which uses a `NonSend` resource to force running on the main thread.
## Migration Guide
- Calls to `.label(MyLabel)` should be replaced with `.in_set(MySet)`
- Stages have been removed. Replace these with system sets, and then add command flushes using the `apply_system_buffers` exclusive system where needed.
- The `CoreStage`, `StartupStage, `RenderStage` and `AssetStage` enums have been replaced with `CoreSet`, `StartupSet, `RenderSet` and `AssetSet`. The same scheduling guarantees have been preserved.
- Systems are no longer added to `CoreSet::Update` by default. Add systems manually if this behavior is needed, although you should consider adding your game logic systems to `CoreSchedule::FixedTimestep` instead for more reliable framerate-independent behavior.
- Similarly, startup systems are no longer part of `StartupSet::Startup` by default. In most cases, this won't matter to you.
- For example, `add_system_to_stage(CoreStage::PostUpdate, my_system)` should be replaced with
- `add_system(my_system.in_set(CoreSet::PostUpdate)`
- When testing systems or otherwise running them in a headless fashion, simply construct and run a schedule using `Schedule::new()` and `World::run_schedule` rather than constructing stages
- Run criteria have been renamed to run conditions. These can now be combined with each other and with states.
- Looping run criteria and state stacks have been removed. Use an exclusive system that runs a schedule if you need this level of control over system control flow.
- For app-level control flow over which schedules get run when (such as for rollback networking), create your own schedule and insert it under the `CoreSchedule::Outer` label.
- Fixed timesteps are now evaluated in a schedule, rather than controlled via run criteria. The `run_fixed_timestep` system runs this schedule between `CoreSet::First` and `CoreSet::PreUpdate` by default.
- Command flush points introduced by `AssetStage` have been removed. If you were relying on these, add them back manually.
- Adding extract systems is now typically done directly on the main app. Make sure the `RenderingAppExtension` trait is in scope, then call `app.add_extract_system(my_system)`.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. You may need to order your movement systems to occur before this system in order to avoid system order ambiguities in culling behavior.
- the `RenderLabel` `AppLabel` was renamed to `RenderApp` for clarity
- `App::add_state` now takes 0 arguments: the starting state is set based on the `Default` impl.
- Instead of creating `SystemSet` containers for systems that run in stages, simply use `.on_enter::<State::Variant>()` or its `on_exit` or `on_update` siblings.
- `SystemLabel` derives should be replaced with `SystemSet`. You will also need to add the `Debug`, `PartialEq`, `Eq`, and `Hash` traits to satisfy the new trait bounds.
- `with_run_criteria` has been renamed to `run_if`. Run criteria have been renamed to run conditions for clarity, and should now simply return a bool.
- States have been dramatically simplified: there is no longer a "state stack". To queue a transition to the next state, call `NextState::set`
## TODO
- [x] remove dead methods on App and World
- [x] add `App::add_system_to_schedule` and `App::add_systems_to_schedule`
- [x] avoid adding the default system set at inappropriate times
- [x] remove any accidental cycles in the default plugins schedule
- [x] migrate benchmarks
- [x] expose explicit labels for the built-in command flush points
- [x] migrate engine code
- [x] remove all mentions of stages from the docs
- [x] verify docs for States
- [x] fix uses of exclusive systems that use .end / .at_start / .before_commands
- [x] migrate RenderStage and AssetStage
- [x] migrate examples
- [x] ensure that transform propagation is exported in a sufficiently public way (the systems are already pub)
- [x] ensure that on_enter schedules are run at least once before the main app
- [x] re-enable opt-in to execution order ambiguities
- [x] revert change to `update_bounds` to ensure it runs in `PostUpdate`
- [x] test all examples
- [x] unbreak directional lights
- [x] unbreak shadows (see 3d_scene, 3d_shape, lighting, transparaency_3d examples)
- [x] game menu example shows loading screen and menu simultaneously
- [x] display settings menu is a blank screen
- [x] `without_winit` example panics
- [x] ensure all tests pass
- [x] SubApp doc test fails
- [x] runs_spawn_local tasks fails
- [x] [Fix panic_when_hierachy_cycle test hanging](https://github.com/alice-i-cecile/bevy/pull/120)
## Points of Difficulty and Controversy
**Reviewers, please give feedback on these and look closely**
1. Default sets, from the RFC, have been removed. These added a tremendous amount of implicit complexity and result in hard to debug scheduling errors. They're going to be tackled in the form of "base sets" by @cart in a followup.
2. The outer schedule controls which schedule is run when `App::update` is called.
3. I implemented `Label for `Box<dyn Label>` for our label types. This enables us to store schedule labels in concrete form, and then later run them. I ran into the same set of problems when working with one-shot systems. We've previously investigated this pattern in depth, and it does not appear to lead to extra indirection with nested boxes.
4. `SubApp::update` simply runs the default schedule once. This sucks, but this whole API is incomplete and this was the minimal changeset.
5. `time_system` and `tick_global_task_pools_on_main_thread` no longer use exclusive systems to attempt to force scheduling order
6. Implemetnation strategy for fixed timesteps
7. `AssetStage` was migrated to `AssetSet` without reintroducing command flush points. These did not appear to be used, and it's nice to remove these bottlenecks.
8. Migration of `bevy_render/lib.rs` and pipelined rendering. The logic here is unusually tricky, as we have complex scheduling requirements.
## Future Work (ideally before 0.10)
- Rename schedule_v3 module to schedule or scheduling
- Add a derive macro to states, and likely a `EnumIter` trait of some form
- Figure out what exactly to do with the "systems added should basically work by default" problem
- Improve ergonomics for working with fixed timesteps and states
- Polish FixedTime API to match Time
- Rebase and merge #7415
- Resolve all internal ambiguities (blocked on better tools, especially #7442)
- Add "base sets" to replace the removed default sets.
# Objective
Removal events are unwieldy and require some knowledge of when to put systems that need to catch events for them, it is very easy to end up missing one and end up with memory leak-ish issues where you don't clean up after yourself.
## Solution
Consolidate removals with the benefits of `Events<...>` (such as double buffering and per system ticks for reading the events) and reduce the special casing of it, ideally I was hoping to move the removals to a `Resource` in the world, but that seems a bit more rough to implement/maintain because of double mutable borrowing issues.
This doesn't go the full length of change detection esque removal detection a la https://github.com/bevyengine/rfcs/pull/44.
Just tries to make the current workflow a bit more user friendly so detecting removals isn't such a scheduling nightmare.
---
## Changelog
- RemovedComponents<T> is now backed by an `Events<Entity>` for the benefits of double buffering.
## Migration Guide
- Add a `mut` for `removed: RemovedComponents<T>` since we are now modifying an event reader internally.
- Iterating over removed components now requires `&mut removed_components` or `removed_components.iter()` instead of `&removed_components`.
# Objective
I found several words in code and docs are incorrect. This should be fixed.
## Solution
- Fix several minor typos
Co-authored-by: Chris Ohk <utilforever@gmail.com>
# Objective
Fixes#3184. Fixes#6640. Fixes#4798. Using `Query::par_for_each(_mut)` currently requires a `batch_size` parameter, which affects how it chunks up large archetypes and tables into smaller chunks to run in parallel. Tuning this value is difficult, as the performance characteristics entirely depends on the state of the `World` it's being run on. Typically, users will just use a flat constant and just tune it by hand until it performs well in some benchmarks. However, this is both error prone and risks overfitting the tuning on that benchmark.
This PR proposes a naive automatic batch-size computation based on the current state of the `World`.
## Background
`Query::par_for_each(_mut)` schedules a new Task for every archetype or table that it matches. Archetypes/tables larger than the batch size are chunked into smaller tasks. Assuming every entity matched by the query has an identical workload, this makes the worst case scenario involve using a batch size equal to the size of the largest matched archetype or table. Conversely, a batch size of `max {archetype, table} size / thread count * COUNT_PER_THREAD` is likely the sweetspot where the overhead of scheduling tasks is minimized, at least not without grouping small archetypes/tables together.
There is also likely a strict minimum batch size below which the overhead of scheduling these tasks is heavier than running the entire thing single-threaded.
## Solution
- [x] Remove the `batch_size` from `Query(State)::par_for_each` and friends.
- [x] Add a check to compute `batch_size = max {archeytpe/table} size / thread count * COUNT_PER_THREAD`
- [x] ~~Panic if thread count is 0.~~ Defer to `for_each` if the thread count is 1 or less.
- [x] Early return if there is no matched table/archetype.
- [x] Add override option for users have queries that strongly violate the initial assumption that all iterated entities have an equal workload.
---
## Changelog
Changed: `Query::par_for_each(_mut)` has been changed to `Query::par_iter(_mut)` and will now automatically try to produce a batch size for callers based on the current `World` state.
## Migration Guide
The `batch_size` parameter for `Query(State)::par_for_each(_mut)` has been removed. These calls will automatically compute a batch size for you. Remove these parameters from all calls to these functions.
Before:
```rust
fn parallel_system(query: Query<&MyComponent>) {
query.par_for_each(32, |comp| {
...
});
}
```
After:
```rust
fn parallel_system(query: Query<&MyComponent>) {
query.par_iter().for_each(|comp| {
...
});
}
```
Co-authored-by: Arnav Choubey <56453634+x-52@users.noreply.github.com>
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Corey Farwell <coreyf@rwell.org>
Co-authored-by: Aevyrie <aevyrie@gmail.com>
# Objective
Complete the first part of the migration detailed in bevyengine/rfcs#45.
## Solution
Add all the new stuff.
### TODO
- [x] Impl tuple methods.
- [x] Impl chaining.
- [x] Port ambiguity detection.
- [x] Write docs.
- [x] ~~Write more tests.~~(will do later)
- [ ] Write changelog and examples here?
- [x] ~~Replace `petgraph`.~~ (will do later)
Co-authored-by: james7132 <contact@jamessliu.com>
Co-authored-by: Michael Hsu <mike.hsu@gmail.com>
Co-authored-by: Mike Hsu <mike.hsu@gmail.com>
# Objective
- Fixes#7066
## Solution
- Split the ChangeDetection trait into ChangeDetection and ChangeDetectionMut
- Added Ref as equivalent to &T with change detection
---
## Changelog
- Support for Ref which allow inspecting change detection flags in an immutable way
## Migration Guide
- While bevy prelude includes both ChangeDetection and ChangeDetectionMut any code explicitly referencing ChangeDetection might need to be updated to ChangeDetectionMut or both. Specifically any reading logic requires ChangeDetection while writes requires ChangeDetectionMut.
use bevy_ecs::change_detection::DetectChanges -> use bevy_ecs::change_detection::{DetectChanges, DetectChangesMut}
- Previously Res had methods to access change detection `is_changed` and `is_added` those methods have been moved to the `DetectChanges` trait. If you are including bevy prelude you will have access to these types otherwise you will need to `use bevy_ecs::change_detection::DetectChanges` to continue using them.
# Objective
Fixes#3310. Fixes#6282. Fixes#6278. Fixes#3666.
## Solution
Split out `!Send` resources into `NonSendResources`. Add a `origin_thread_id` to all `!Send` Resources, check it on dropping `NonSendResourceData`, if there's a mismatch, panic. Moved all of the checks that `MainThreadValidator` would do into `NonSendResources` instead.
All `!Send` resources now individually track which thread they were inserted from. This is validated against for every access, mutation, and drop that could be done against the value.
A regression test using an altered version of the example from #3310 has been added.
This is a stopgap solution for the current status quo. A full solution may involve fully removing `!Send` resources/components from `World`, which will likely require a much more thorough design on how to handle the existing in-engine and ecosystem use cases.
This PR also introduces another breaking change:
```rust
use bevy_ecs::prelude::*;
#[derive(Resource)]
struct Resource(u32);
fn main() {
let mut world = World::new();
world.insert_resource(Resource(1));
world.insert_non_send_resource(Resource(2));
let res = world.get_resource_mut::<Resource>().unwrap();
assert_eq!(res.0, 2);
}
```
This code will run correctly on 0.9.1 but not with this PR, since NonSend resources and normal resources have become actual distinct concepts storage wise.
## Changelog
Changed: Fix soundness bug with `World: Send`. Dropping a `World` that contains a `!Send` resource on the wrong thread will now panic.
## Migration Guide
Normal resources and `NonSend` resources no longer share the same backing storage. If `R: Resource`, then `NonSend<R>` and `Res<R>` will return different instances from each other. If you are using both `Res<T>` and `NonSend<T>` (or their mutable variants), to fetch the same resources, it's strongly advised to use `Res<T>`.
# Objective
[Rust 1.66](https://blog.rust-lang.org/inside-rust/2022/12/12/1.66.0-prerelease.html) is coming in a few days, and bevy doesn't build with it.
Fix that.
## Solution
Replace output from a trybuild test, and fix a few new instances of `needless_borrow` and `unnecessary_cast` that are now caught.
## Note
Due to the trybuild test, this can't be merged until 1.66 is released.
# Objective
Fixes#6224, add ``dbg``, ``info``, ``warn`` and ``error`` system piping adapter variants to expand #5776, which call the corresponding re-exported [bevy_log macros](https://docs.rs/bevy/latest/bevy/log/macro.info.html) when the result is an error.
## Solution
* Added ``dbg``, ``info``, ``warn`` and ``error`` system piping adapter variants to ``system_piping.rs``.
* Modified and added tests for these under examples in ``system_piping.rs``.
# Objective
#6547 accidentally broke change detection for SparseSet components by using `Ticks::from_tick_cells` with the wrong argument order.
## Solution
Use the right argument order. Add a regression test.
# Objective
The soundness of the ECS `World` partially relies on the correctness of the state of `Entities` stored within it. We're currently allowing users to (unsafely) mutate it, as well as readily construct it without using a `World`. While this is not strictly unsound so long as users (including `bevy_render`) safely use the APIs, it's a fairly easy path to unsoundness without much of a guard rail.
Addresses #3362 for `bevy_ecs::entity`. Incorporates the changes from #3985.
## Solution
Remove `Entities`'s `Default` implementation and force access to the type to only be through a properly constructed `World`.
Additional cleanup for other parts of `bevy_ecs::entity`:
- `Entity::index` and `Entity::generation` are no longer `pub(crate)`, opting to force the rest of bevy_ecs to use the public interface to access these values.
- `EntityMeta` is no longer `pub` and also not `pub(crate)` to attempt to cut down on updating `generation` without going through an `Entities` API. It's currently inaccessible except via the `pub(crate)` Vec on `Entities`, there was no way for an outside user to use it.
- Added `Entities::set`, an unsafe `pub(crate)` API for setting the location of an Entity (parallel to `Entities::get`) that replaces the internal case where we need to set the location of an entity when it's been spawned, moved, or despawned.
- `Entities::alloc_at_without_replacement` is only used in `World::get_or_spawn` within the first party crates, and I cannot find a public use of this API in any ecosystem crate that I've checked (via GitHub search).
- Attempted to document the few remaining undocumented public APIs in the module.
---
## Changelog
Removed: `Entities`'s `Default` implementation.
Removed: `EntityMeta`
Removed: `Entities::alloc_at_without_replacement` and `AllocAtWithoutReplacement`.
Co-authored-by: james7132 <contact@jamessliu.com>
Co-authored-by: James Liu <contact@jamessliu.com>
This reverts commit 53d387f340.
# Objective
Reverts #6448. This didn't have the intended effect: we're now getting bevy::prelude shown in the docs again.
Co-authored-by: Alejandro Pascual <alejandro.pascual.pozo@gmail.com>
# Objective
- Right now re-exports are completely hidden in prelude docs.
- Fixes#6433
## Solution
- We could show the re-exports without inlining their documentation.
# Objective
Fixes#6059, changing all incorrect occurrences of ``id`` in the ``entity`` module to ``index``:
* struct level documentation,
* ``id`` struct field,
* ``id`` method and its documentation.
## Solution
Renaming and verifying using CI.
Co-authored-by: Edvin Kjell <43633999+Edwox@users.noreply.github.com>
# Objective
Clean up code surrounding fetch by pulling out the common parts into the iteration code.
## Solution
Merge `Fetch::table_fetch` and `Fetch::archetype_fetch` into a single API: `Fetch::fetch(&mut self, entity: &Entity, table_row: &usize)`. This provides everything any fetch requires to internally decide which storage to read from and get the underlying data. All of these functions are marked as `#[inline(always)]` and the arguments are passed as references to attempt to optimize out the argument that isn't being used.
External to `Fetch`, Query iteration has been changed to keep track of the table row and entity outside of fetch, which moves a lot of the expensive bookkeeping `Fetch` structs had previously done internally into the outer loop.
~~TODO: Benchmark, docs~~ Done.
---
## Changelog
Changed: `Fetch::table_fetch` and `Fetch::archetype_fetch` have been merged into a single `Fetch::fetch` function.
## Migration Guide
TODO
Co-authored-by: Brian Merchant <bhmerchang@gmail.com>
Co-authored-by: Saverio Miroddi <saverio.pub2@gmail.com>
# Objective
Fixes#5559
Replaces #5628
## Solution
Because the generated method from_components() creates an instance of Self my implementation requires any field type that is marked to be ignored to implement Default.
---
## Changelog
Added the possibility to ignore fields in a bundle with `#[bundle(ignore)]`. Typically used when `PhantomData` needs to be added to a `Bundle`.
# Objective
At least partially addresses #6282.
Resources are currently stored as a dedicated Resource archetype (ID 1). This allows for easy code reusability, but unnecessarily adds 72 bytes (on 64-bit systems) to the struct that is only used for that one archetype. It also requires several fields to be `pub(crate)` which isn't ideal.
This should also remove one sparse-set lookup from fetching, inserting, and removing resources from a `World`.
## Solution
- Add `Resources` parallel to `Tables` and `SparseSets` and extract the functionality used by `Archetype` in it.
- Remove `unique_components` from `Archetype`
- Remove the `pub(crate)` on `Archetype::components`.
- Remove `ArchetypeId::RESOURCE`
- Remove `Archetypes::resource` and `Archetypes::resource_mut`
---
## Changelog
Added: `Resources` type to store resources.
Added: `Storages::resource`
Removed: `ArchetypeId::RESOURCE`
Removed: `Archetypes::resource` and `Archetypes::resources`
Removed: `Archetype::unique_components` and `Archetypes::unique_components_mut`
## Migration Guide
Resources have been moved to `Resources` under `Storages` in `World`. All code dependent on `Archetype::unique_components(_mut)` should access it via `world.storages().resources()` instead.
All APIs accessing the raw data of individual resources (mutable *and* read-only) have been removed as these APIs allowed for unsound unsafe code. All usages of these APIs should be changed to use `World::{get, insert, remove}_resource`.
# Objective
> System chaining is a confusing name: it implies the ability to construct non-linear graphs, and suggests a sense of system ordering that is only incidentally true. Instead, it actually works by passing data from one system to the next, much like the pipe operator.
> In the accepted [stageless RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/45-stageless.md), this concept is renamed to piping, and "system chaining" is used to construct groups of systems with ordering dependencies between them.
Fixes#6225.
## Changelog
System chaining has been renamed to system piping to improve clarity (and free up the name for new ordering APIs).
## Migration Guide
The `.chain(handler_system)` method on systems is now `.pipe(handler_system)`.
The `IntoChainSystem` trait is now `IntoPipeSystem`, and the `ChainSystem` struct is now `PipeSystem`.
# Objective
Relaxes the trait bound for `World::resource_scope` to allow non-send resources. Fixes#6037.
## Solution
No big changes in code had to be made. Added a check so that the non-send resources won't be accessed from a different thread.
---
## Changelog
- `World::resource_scope` accepts non-send resources now
- `World::resource_scope` verifies non-send access if the resource is non-send
- Two new tests are added, one for valid use of `World::resource_scope` with a non-send resource, and one for invalid use (calling it from a different thread, resulting in panic)
Co-authored-by: Dawid Piotrowski <41804418+Pietrek14@users.noreply.github.com>
# Objective
The [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) involves allowing exclusive systems to be referenced and ordered relative to parallel systems. We've agreed that unifying systems under `System` is the right move.
This is an alternative to #4166 (see rationale in the comments I left there). Note that this builds on the learnings established there (and borrows some patterns).
## Solution
This unifies parallel and exclusive systems under the shared `System` trait, removing the old `ExclusiveSystem` trait / impls. This is accomplished by adding a new `ExclusiveFunctionSystem` impl similar to `FunctionSystem`. It is backed by `ExclusiveSystemParam`, which is similar to `SystemParam`. There is a new flattened out SystemContainer api (which cuts out a lot of trait and type complexity).
This means you can remove all cases of `exclusive_system()`:
```rust
// before
commands.add_system(some_system.exclusive_system());
// after
commands.add_system(some_system);
```
I've also implemented `ExclusiveSystemParam` for `&mut QueryState` and `&mut SystemState`, which makes this possible in exclusive systems:
```rust
fn some_exclusive_system(
world: &mut World,
transforms: &mut QueryState<&Transform>,
state: &mut SystemState<(Res<Time>, Query<&Player>)>,
) {
for transform in transforms.iter(world) {
println!("{transform:?}");
}
let (time, players) = state.get(world);
for player in players.iter() {
println!("{player:?}");
}
}
```
Note that "exclusive function systems" assume `&mut World` is present (and the first param). I think this is a fair assumption, given that the presence of `&mut World` is what defines the need for an exclusive system.
I added some targeted SystemParam `static` constraints, which removed the need for this:
``` rust
fn some_exclusive_system(state: &mut SystemState<(Res<'static, Time>, Query<&'static Player>)>) {}
```
## Related
- #2923
- #3001
- #3946
## Changelog
- `ExclusiveSystem` trait (and implementations) has been removed in favor of sharing the `System` trait.
- `ExclusiveFunctionSystem` and `ExclusiveSystemParam` were added, enabling flexible exclusive function systems
- `&mut SystemState` and `&mut QueryState` now implement `ExclusiveSystemParam`
- Exclusive and parallel System configuration is now done via a unified `SystemDescriptor`, `IntoSystemDescriptor`, and `SystemContainer` api.
## Migration Guide
Calling `.exclusive_system()` is no longer required (or supported) for converting exclusive system functions to exclusive systems:
```rust
// Old (0.8)
app.add_system(some_exclusive_system.exclusive_system());
// New (0.9)
app.add_system(some_exclusive_system);
```
Converting "normal" parallel systems to exclusive systems is done by calling the exclusive ordering apis:
```rust
// Old (0.8)
app.add_system(some_system.exclusive_system().at_end());
// New (0.9)
app.add_system(some_system.at_end());
```
Query state in exclusive systems can now be cached via ExclusiveSystemParams, which should be preferred for clarity and performance reasons:
```rust
// Old (0.8)
fn some_system(world: &mut World) {
let mut transforms = world.query::<&Transform>();
for transform in transforms.iter(world) {
}
}
// New (0.9)
fn some_system(world: &mut World, transforms: &mut QueryState<&Transform>) {
for transform in transforms.iter(world) {
}
}
```
# Objective
Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands).
## Solution
All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input:
```rust
// before:
commands
.spawn()
.insert((A, B, C));
world
.spawn()
.insert((A, B, C);
// after
commands.spawn((A, B, C));
world.spawn((A, B, C));
```
All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api.
By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`).
This improves spawn performance by over 10%:
To take this measurement, I added a new `world_spawn` benchmark.
Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main.
**Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).**
---
## Changelog
- All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input
- All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api
- World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior.
## Migration Guide
```rust
// Old (0.8):
commands
.spawn()
.insert_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));
// Old (0.8):
commands.spawn_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));
// Old (0.8):
let entity = commands.spawn().id();
// New (0.9)
let entity = commands.spawn_empty().id();
// Old (0.8)
let entity = world.spawn().id();
// New (0.9)
let entity = world.spawn_empty();
```
# Objective
Take advantage of the "impl Bundle for Component" changes in #2975 / add the follow up changes discussed there.
## Solution
- Change `insert` and `remove` to accept a Bundle instead of a Component (for both Commands and World)
- Deprecate `insert_bundle`, `remove_bundle`, and `remove_bundle_intersection`
- Add `remove_intersection`
---
## Changelog
- Change `insert` and `remove` now accept a Bundle instead of a Component (for both Commands and World)
- `insert_bundle` and `remove_bundle` are deprecated
## Migration Guide
Replace `insert_bundle` with `insert`:
```rust
// Old (0.8)
commands.spawn().insert_bundle(SomeBundle::default());
// New (0.9)
commands.spawn().insert(SomeBundle::default());
```
Replace `remove_bundle` with `remove`:
```rust
// Old (0.8)
commands.entity(some_entity).remove_bundle::<SomeBundle>();
// New (0.9)
commands.entity(some_entity).remove::<SomeBundle>();
```
Replace `remove_bundle_intersection` with `remove_intersection`:
```rust
// Old (0.8)
world.entity_mut(some_entity).remove_bundle_intersection::<SomeBundle>();
// New (0.9)
world.entity_mut(some_entity).remove_intersection::<SomeBundle>();
```
Consider consolidating as many operations as possible to improve ergonomics and cut down on archetype moves:
```rust
// Old (0.8)
commands.spawn()
.insert_bundle(SomeBundle::default())
.insert(SomeComponent);
// New (0.9) - Option 1
commands.spawn().insert((
SomeBundle::default(),
SomeComponent,
))
// New (0.9) - Option 2
commands.spawn_bundle((
SomeBundle::default(),
SomeComponent,
))
```
## Next Steps
Consider changing `spawn` to accept a bundle and deprecate `spawn_bundle`.
@BoxyUwU this is your fault.
Also cart didn't arrive in time to tell us not to do this.
# Objective
- Fix#2974
## Solution
- The first commit just does the actual change
- Follow up commits do steps to prove that this method works to unify as required, but this does not remove `insert_bundle`.
## Changelog
### Changed
Nested bundles now collapse automatically, and every `Component` now implements `Bundle`.
This means that you can combine bundles and components arbitrarily, for example:
```rust
// before:
.insert(A).insert_bundle(MyBBundle{..})
// after:
.insert_bundle((A, MyBBundle {..}))
```
Note that there will be a follow up PR that removes the current `insert` impl and renames `insert_bundle` to `insert`.
### Removed
The `bundle` attribute in `derive(Bundle)`.
## Migration guide
In `derive(Bundle)`, the `bundle` attribute has been removed. Nested bundles are not collapsed automatically. You should remove `#[bundle]` attributes.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Fixes Issue #6005.
## Solution
Replaced WorldQuery with ReadOnlyWorldQuery on F generic in Query filters and QueryState to restrict its trait bound.
## Migration Guide
Query filter (`F`) generics are now bound by `ReadOnlyWorldQuery`, rather than `WorldQuery`. If for some reason you were requesting `Query<&A, &mut B>`, please use `Query<&A, With<B>>` instead.
# Objective
Ambiguity sets are used to ignore system order ambiguities between groups of systems. However, they are not very useful: they are clunky, poorly integrated, and generally hampered by the difficulty using (or discovering) the ambiguity detector.
As a first step to the work in #4299, we're removing them.
## Migration Guide
Ambiguity sets have been removed.
# Objective
Right now, users have to implement basic system adapters such as `Option` <-> `Result` conversions by themselves. This is slightly annoying and discourages the use of system chaining.
## Solution
Add the module `system_adapter` to the prelude, which contains a collection of common adapters. This is very ergonomic in practice.
## Examples
Convenient early returning.
```rust
use bevy::prelude::*;
App::new()
// If the system fails, just try again next frame.
.add_system(pet_dog.chain(system_adapter::ignore))
.run();
#[derive(Component)]
struct Dog;
fn pet_dog(dogs: Query<(&Name, Option<&Parent>), With<Dog>>) -> Option<()> {
let (dog, dad) = dogs.iter().next()?;
println!("You pet {dog}. He/she/they are a good boy/girl/pupper.");
let (dad, _) = dogs.get(dad?.get()).ok()?;
println!("Their dad's name is {dad}");
Some(())
}
```
Converting the output of a system
```rust
use bevy::prelude::*;
App::new()
.add_system(
find_name
.chain(system_adapter::new(String::from))
.chain(spawn_with_name),
)
.run();
fn find_name() -> &'static str { /* ... */ }
fn spawn_with_name(In(name): In<String>, mut commands: Commands) {
commands.spawn().insert(Name::new(name));
}
```
---
## Changelog
* Added the module `bevy_ecs::prelude::system_adapter`, which contains a collection of common system chaining adapters.
* `new` - Converts a regular fn to a system adapter.
* `unwrap` - Similar to `Result::unwrap`
* `ignore` - Discards the output of the previous system.
*This PR description is an edited copy of #5007, written by @alice-i-cecile.*
# Objective
Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds.
While ergonomic, this results in several drawbacks:
* it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource
* it is challenging to discover if a type is intended to be used as a resource
* we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component).
* dependencies can use the same Rust type as a resource in invisibly conflicting ways
* raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values
* we cannot capture a definitive list of possible resources to display to users in an editor
## Notes to reviewers
* Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits.
*ira: My commits are not as well organized :')*
* I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does.
* I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981.
## Changelog
`Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro.
## Migration Guide
Add `#[derive(Resource)]` to all types you are using as a resource.
If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics.
`ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing.
Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead.
Co-authored-by: Alice <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
`SAFETY` comments are meant to be placed before `unsafe` blocks and should contain the reasoning of why in this case the usage of unsafe is okay. This is useful when reading the code because it makes it clear which assumptions are required for safety, and makes it easier to spot possible unsoundness holes. It also forces the code writer to think of something to write and maybe look at the safety contracts of any called unsafe methods again to double-check their correct usage.
There's a clippy lint called `undocumented_unsafe_blocks` which warns when using a block without such a comment.
## Solution
- since clippy expects `SAFETY` instead of `SAFE`, rename those
- add `SAFETY` comments in more places
- for the last remaining 3 places, add an `#[allow()]` and `// TODO` since I wasn't comfortable enough with the code to justify their safety
- add ` #![warn(clippy::undocumented_unsafe_blocks)]` to `bevy_ecs`
### Note for reviewers
The first commit only renames `SAFETY` to `SAFE` so it doesn't need a thorough review.
cb042a416e..55cef2d6fa is the diff for all other changes.
### Safety comments where I'm not too familiar with the code
774012ece5/crates/bevy_ecs/src/entity/mod.rs (L540-L546)774012ece5/crates/bevy_ecs/src/world/entity_ref.rs (L249-L252)
### Locations left undocumented with a `TODO` comment
5dde944a30/crates/bevy_ecs/src/schedule/executor_parallel.rs (L196-L199)5dde944a30/crates/bevy_ecs/src/world/entity_ref.rs (L287-L289)5dde944a30/crates/bevy_ecs/src/world/entity_ref.rs (L413-L415)
Co-authored-by: Jakob Hellermann <hellermann@sipgate.de>
# Objective
We don't have reflection for resources.
## Solution
Introduce reflection for resources.
Continues #3580 (by @Davier), related to #3576.
---
## Changelog
### Added
* Reflection on a resource type (by adding `ReflectResource`):
```rust
#[derive(Reflect)]
#[reflect(Resource)]
struct MyResourse;
```
### Changed
* Rename `ReflectComponent::add_component` into `ReflectComponent::insert_component` for consistency.
## Migration Guide
* Rename `ReflectComponent::add_component` into `ReflectComponent::insert_component`.
# Objective
This is a common and useful type. I frequently use this when working with `Events` resource directly, typically when caching the data or manipulating the `World` directly.
This is also useful when manually configuring the cleanup strategy for events.
Right now, a direct reference to the target TaskPool is required to launch tasks on the pools, despite the three newtyped pools (AsyncComputeTaskPool, ComputeTaskPool, and IoTaskPool) effectively acting as global instances. The need to pass a TaskPool reference adds notable friction to spawning subtasks within existing tasks. Possible use cases for this may include chaining tasks within the same pool like spawning separate send/receive I/O tasks after waiting on a network connection to be established, or allowing cross-pool dependent tasks like starting dependent multi-frame computations following a long I/O load.
Other task execution runtimes provide static access to spawning tasks (i.e. `tokio::spawn`), which is notably easier to use than the reference passing required by `bevy_tasks` right now.
This PR makes does the following:
* Adds `*TaskPool::init` which initializes a `OnceCell`'ed with a provided TaskPool. Failing if the pool has already been initialized.
* Adds `*TaskPool::get` which fetches the initialized global pool of the respective type or panics. This generally should not be an issue in normal Bevy use, as the pools are initialized before they are accessed.
* Updated default task pool initialization to either pull the global handles and save them as resources, or if they are already initialized, pull the a cloned global handle as the resource.
This should make it notably easier to build more complex task hierarchies for dependent tasks. It should also make writing bevy-adjacent, but not strictly bevy-only plugin crates easier, as the global pools ensure it's all running on the same threads.
One alternative considered is keeping a thread-local reference to the pool for all threads in each pool to enable the same `tokio::spawn` interface. This would spawn tasks on the same pool that a task is currently running in. However this potentially leads to potential footgun situations where long running blocking tasks run on `ComputeTaskPool`.
(follow-up to #4423)
# Objective
Currently, it isn't possible to easily fire commands from within par_for_each blocks. This PR allows for issuing commands from within parallel scopes.
# Objective
Fixes#3183. Requiring a `&TaskPool` parameter is sort of meaningless if the only correct one is to use the one provided by `Res<ComputeTaskPool>` all the time.
## Solution
Have `QueryState` save a clone of the `ComputeTaskPool` which is used for all `par_for_each` functions.
~~Adds a small overhead of the internal `Arc` clone as a part of the startup, but the ergonomics win should be well worth this hardly-noticable overhead.~~
Updated the docs to note that it will panic the task pool is not present as a resource.
# Future Work
If https://github.com/bevyengine/rfcs/pull/54 is approved, we can replace these resource lookups with a static function call instead to get the `ComputeTaskPool`.
---
## Changelog
Removed: The `task_pool` parameter of `Query(State)::par_for_each(_mut)`. These calls will use the `World`'s `ComputeTaskPool` resource instead.
## Migration Guide
The `task_pool` parameter for `Query(State)::par_for_each(_mut)` has been removed. Remove these parameters from all calls to these functions.
Before:
```rust
fn parallel_system(
task_pool: Res<ComputeTaskPool>,
query: Query<&MyComponent>,
) {
query.par_for_each(&task_pool, 32, |comp| {
...
});
}
```
After:
```rust
fn parallel_system(query: Query<&MyComponent>) {
query.par_for_each(32, |comp| {
...
});
}
```
If using `Query(State)` outside of a system run by the scheduler, you may need to manually configure and initialize a `ComputeTaskPool` as a resource in the `World`.
# Objective
`bevy_ecs` assumes that `u32 as usize` is a lossless operation and in a few cases relies on this for soundness and correctness. The only platforms that Rust compiles to where this invariant is broken are 16-bit systems.
A very clear example of this behavior is in the SparseSetIndex impl for Entity, where it converts a u32 into a usize to act as an index. If usize is 16-bit, the conversion will overflow and provide the caller with the wrong index. This can easily result in previously unforseen aliased mutable borrows (i.e. Query::get_many_mut).
## Solution
Explicitly fail compilation on 16-bit platforms instead of introducing UB.
Properly supporting 16-bit systems will likely need a workable use case first.
---
## Changelog
Removed: Ability to compile `bevy_ecs` on 16-bit platforms.
## Migration Guide
`bevy_ecs` will now explicitly fail to compile on 16-bit platforms. If this is required, there is currently no alternative. Please file an issue (https://github.com/bevyengine/bevy/issues) to help detail your use case.
# Objective
The pointer types introduced in #3001 are useful not just in `bevy_ecs`, but also in crates like `bevy_reflect` (#4475) or even outside of bevy.
## Solution
Extract `Ptr<'a>`, `PtrMut<'a>`, `OwnedPtr<'a>`, `ThinSlicePtr<'a, T>` and `UnsafeCellDeref` from `bevy_ecs::ptr` into `bevy_ptr`.
**Note:** `bevy_ecs` still reexports the `bevy_ptr` as `bevy_ecs::ptr` so that crates like `bevy_transform` can use the `Bundle` derive without needing to depend on `bevy_ptr` themselves.
# Objective
`bevy_ecs` has large amounts of unsafe code which is hard to get right and makes it difficult to audit for soundness.
## Solution
Introduce lifetimed, type-erased pointers: `Ptr<'a>` `PtrMut<'a>` `OwningPtr<'a>'` and `ThinSlicePtr<'a, T>` which are newtypes around a raw pointer with a lifetime and conceptually representing strong invariants about the pointee and validity of the pointer.
The process of converting bevy_ecs to use these has already caught multiple cases of unsound behavior.
## Changelog
TL;DR for release notes: `bevy_ecs` now uses lifetimed, type-erased pointers internally, significantly improving safety and legibility without sacrificing performance. This should have approximately no end user impact, unless you were meddling with the (unfortunately public) internals of `bevy_ecs`.
- `Fetch`, `FilterFetch` and `ReadOnlyFetch` trait no longer have a `'state` lifetime
- this was unneeded
- `ReadOnly/Fetch` associated types on `WorldQuery` are now on a new `WorldQueryGats<'world>` trait
- was required to work around lack of Generic Associated Types (we wish to express `type Fetch<'a>: Fetch<'a>`)
- `derive(WorldQuery)` no longer requires `'w` lifetime on struct
- this was unneeded, and improves the end user experience
- `EntityMut::get_unchecked_mut` returns `&'_ mut T` not `&'w mut T`
- allows easier use of unsafe API with less footguns, and can be worked around via lifetime transmutery as a user
- `Bundle::from_components` now takes a `ctx` parameter to pass to the `FnMut` closure
- required because closure return types can't borrow from captures
- `Fetch::init` takes `&'world World`, `Fetch::set_archetype` takes `&'world Archetype` and `&'world Tables`, `Fetch::set_table` takes `&'world Table`
- allows types implementing `Fetch` to store borrows into world
- `WorldQuery` trait now has a `shrink` fn to shorten the lifetime in `Fetch::<'a>::Item`
- this works around lack of subtyping of assoc types, rust doesnt allow you to turn `<T as Fetch<'static>>::Item'` into `<T as Fetch<'a>>::Item'`
- `QueryCombinationsIter` requires this
- Most types implementing `Fetch` now have a lifetime `'w`
- allows the fetches to store borrows of world data instead of using raw pointers
## Migration guide
- `EntityMut::get_unchecked_mut` returns a more restricted lifetime, there is no general way to migrate this as it depends on your code
- `Bundle::from_components` implementations must pass the `ctx` arg to `func`
- `Bundle::from_components` callers have to use a fn arg instead of closure captures for borrowing from world
- Remove lifetime args on `derive(WorldQuery)` structs as it is nonsensical
- `<Q as WorldQuery>::ReadOnly/Fetch` should be changed to either `RO/QueryFetch<'world>` or `<Q as WorldQueryGats<'world>>::ReadOnly/Fetch`
- `<F as Fetch<'w, 's>>` should be changed to `<F as Fetch<'w>>`
- Change the fn sigs of `Fetch::init/set_archetype/set_table` to match respective trait fn sigs
- Implement the required `fn shrink` on any `WorldQuery` implementations
- Move assoc types `Fetch` and `ReadOnlyFetch` on `WorldQuery` impls to `WorldQueryGats` impls
- Pass an appropriate `'world` lifetime to whatever fetch struct you are for some reason using
### Type inference regression
in some cases rustc may give spurrious errors when attempting to infer the `F` parameter on a query/querystate this can be fixed by manually specifying the type, i.e. `QueryState:🆕:<_, ()>(world)`. The error is rather confusing:
```rust=
error[E0271]: type mismatch resolving `<() as Fetch<'_>>::Item == bool`
--> crates/bevy_pbr/src/render/light.rs:1413:30
|
1413 | main_view_query: QueryState::new(world),
| ^^^^^^^^^^^^^^^ expected `bool`, found `()`
|
= note: required because of the requirements on the impl of `for<'x> FilterFetch<'x>` for `<() as WorldQueryGats<'x>>::Fetch`
note: required by a bound in `bevy_ecs::query::QueryState::<Q, F>::new`
--> crates/bevy_ecs/src/query/state.rs:49:32
|
49 | for<'x> QueryFetch<'x, F>: FilterFetch<'x>,
| ^^^^^^^^^^^^^^^ required by this bound in `bevy_ecs::query::QueryState::<Q, F>::new`
```
---
Made with help from @BoxyUwU and @alice-i-cecile
Co-authored-by: Boxy <supbscripter@gmail.com>
## Objective
This fixes#1686.
`size_hint` can be useful even if a little niche. For example,
`collect::<Vec<_>>()` uses the `size_hint` of Iterator it collects from
to pre-allocate a memory slice large enough to not require re-allocating
when pushing all the elements of the iterator.
## Solution
To this effect I made the following changes:
* Add a `IS_ARCHETYPAL` associated constant to the `Fetch` trait,
this constant tells us when it is safe to assume that the `Fetch`
relies exclusively on archetypes to filter queried entities
* Add `IS_ARCHETYPAL` to all the implementations of `Fetch`
* Use that constant in `QueryIter::size_hint` to provide a more useful
## Migration guide
The new associated constant is an API breaking change. For the user,
if they implemented a custom `Fetch`, it means they have to add this
associated constant to their implementation. Either `true` if it doesn't limit
the number of entities returned in a query beyond that of archetypes, or
`false` for when it does.
Remove the 'chaining' api, as it's peculiar
~~Implement the label traits for `Box<dyn ThatTrait>` (n.b. I'm not confident about this change, but it was the quickest path to not regressing)~~
Remove the need for '`.system`' when using run criteria piping
# Objective
Add a system parameter `ParamSet` to be used as container for conflicting parameters.
## Solution
Added two methods to the SystemParamState trait, which gives the access used by the parameter. Did the implementation. Added some convenience methods to FilteredAccessSet. Changed `get_conflicts` to return every conflicting component instead of breaking on the first conflicting `FilteredAccess`.
Co-authored-by: bilsen <40690317+bilsen@users.noreply.github.com>
# Objective
Fixes#1529
Run bevy_ecs in miri
## Solution
- Don't set thread names when running in miri rust-lang/miri/issues/1717
- Update `event-listener` to `2.5.2` as previous versions have UB that is detected by miri: [event-listener commit](1fa31c553e)
- Ignore memory leaks when running in miri as they are impossible to track down rust-lang/miri/issues/1481
- Make `table_add_remove_many` test less "many" because miri is really quite slow :)
- Make CI run `RUSTFLAGS="-Zrandomize-layout" MIRIFLAGS="-Zmiri-ignore-leaks -Zmiri-tag-raw-pointers -Zmiri-disable-isolation" cargo +nightly miri test -p bevy_ecs`
This adds the concept of "default labels" for systems (currently scoped to "parallel systems", but this could just as easily be implemented for "exclusive systems"). Function systems now include their function's `SystemTypeIdLabel` by default.
This enables the following patterns:
```rust
// ordering two systems without manually defining labels
app
.add_system(update_velocity)
.add_system(movement.after(update_velocity))
// ordering sets of systems without manually defining labels
app
.add_system(foo)
.add_system_set(
SystemSet::new()
.after(foo)
.with_system(bar)
.with_system(baz)
)
```
Fixes: #4219
Related to: #4220
Credit to @aevyrie @alice-i-cecile @DJMcNab (and probably others) for proposing (and supporting) this idea about a year ago. I was a big dummy that both shut down this (very good) idea and then forgot I did that. Sorry. You all were right!
# Objective
- In the large majority of cases, users were calling `.unwrap()` immediately after `.get_resource`.
- Attempting to add more helpful error messages here resulted in endless manual boilerplate (see #3899 and the linked PRs).
## Solution
- Add an infallible variant named `.resource` and so on.
- Use these infallible variants over `.get_resource().unwrap()` across the code base.
## Notes
I did not provide equivalent methods on `WorldCell`, in favor of removing it entirely in #3939.
## Migration Guide
Infallible variants of `.get_resource` have been added that implicitly panic, rather than needing to be unwrapped.
Replace `world.get_resource::<Foo>().unwrap()` with `world.resource::<Foo>()`.
## Impact
- `.unwrap` search results before: 1084
- `.unwrap` search results after: 942
- internal `unwrap_or_else` calls added: 4
- trivial unwrap calls removed from tests and code: 146
- uses of the new `try_get_resource` API: 11
- percentage of the time the unwrapping API was used internally: 93%
# Objective
- Fix the ugliness of the `config` api.
- Supercedes #2440, #2463, #2491
## Solution
- Since #2398, capturing closure systems have worked.
- Use those instead where we needed config before
- Remove the rest of the config api.
- Related: #2777
What is says on the tin.
This has got more to do with making `clippy` slightly more *quiet* than it does with changing anything that might greatly impact readability or performance.
that said, deriving `Default` for a couple of structs is a nice easy win
# Objective
- Fixes#3078
- Fixes#1397
## Solution
- Implement Commands::init_resource.
- Also implement for World, for consistency and to simplify internal structure.
- While we're here, clean up some of the docs for Command and World resource modification.
Implements a new Queryable called AnyOf, which will return an item as long as at least one of it's requested Queryables returns something. For example, a `Query<AnyOf<(&A, &B, &C)>>` will return items with type `(Option<&A>, Option<&B>, Option<&C>)`, and will guarantee that for every element at least one of the option s is Some. This is a shorthand for queries like `Query<(Option<&A>, Option<&B>, Option<&C>), Or<(With<A>, With<B>, With&C>)>>`.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Calling .id() has no purpose unless you use the Entity returned
- This is an easy source of confusion for beginners.
- This is easily missed during refactors.
## Solution
- Mark the appropriate methods as #[must_use]
Fixes#2566Fixes#3005
There are only READMEs in the 4 crates here (with the exception of bevy itself).
Those 4 crates are ecs, reflect, tasks, and transform.
These should each now include their respective README files.
Co-authored-by: Hoidigan <57080125+Hoidigan@users.noreply.github.com>
Co-authored-by: Daniel Nelsen <57080125+Hoidigan@users.noreply.github.com>
This implements the most minimal variant of #1843 - a derive for marker trait. This is a prerequisite to more complicated features like statically defined storage type or opt-out component reflection.
In order to make component struct's purpose explicit and avoid misuse, it must be annotated with `#[derive(Component)]` (manual impl is discouraged for compatibility). Right now this is just a marker trait, but in the future it might be expanded. Making this change early allows us to make further changes later without breaking backward compatibility for derive macro users.
This already prevents a lot of issues, like using bundles in `insert` calls. Primitive types are no longer valid components as well. This can be easily worked around by adding newtype wrappers and deriving `Component` for them.
One funny example of prevented bad code (from our own tests) is when an newtype struct or enum variant is used. Previously, it was possible to write `insert(Newtype)` instead of `insert(Newtype(value))`. That code compiled, because function pointers (in this case newtype struct constructor) implement `Send + Sync + 'static`, so we allowed them to be used as components. This is no longer the case and such invalid code will trigger a compile error.
Co-authored-by: = <=>
Co-authored-by: TheRawMeatball <therawmeatball@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
