mirror of
https://github.com/bevyengine/bevy
synced 2024-12-23 03:23:20 +00:00
dc3f801239
# 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) { } } ```
1617 lines
50 KiB
Rust
1617 lines
50 KiB
Rust
pub use crate::change_detection::{NonSendMut, ResMut};
|
|
use crate::{
|
|
archetype::{Archetype, Archetypes},
|
|
bundle::Bundles,
|
|
change_detection::Ticks,
|
|
component::{Component, ComponentId, ComponentTicks, Components},
|
|
entity::{Entities, Entity},
|
|
query::{
|
|
Access, FilteredAccess, FilteredAccessSet, QueryState, ReadOnlyWorldQuery, WorldQuery,
|
|
},
|
|
system::{CommandQueue, Commands, Query, SystemMeta},
|
|
world::{FromWorld, World},
|
|
};
|
|
pub use bevy_ecs_macros::Resource;
|
|
pub use bevy_ecs_macros::SystemParam;
|
|
use bevy_ecs_macros::{all_tuples, impl_param_set};
|
|
use bevy_ptr::UnsafeCellDeref;
|
|
use bevy_utils::synccell::SyncCell;
|
|
use std::{
|
|
borrow::Cow,
|
|
fmt::Debug,
|
|
marker::PhantomData,
|
|
ops::{Deref, DerefMut},
|
|
};
|
|
|
|
/// A parameter that can be used in a [`System`](super::System).
|
|
///
|
|
/// # Derive
|
|
///
|
|
/// This trait can be derived with the [`derive@super::SystemParam`] macro.
|
|
/// This macro only works if each field on the derived struct implements [`SystemParam`].
|
|
/// Note: There are additional requirements on the field types.
|
|
/// See the *Generic `SystemParam`s* section for details and workarounds of the probable
|
|
/// cause if this derive causes an error to be emitted.
|
|
///
|
|
///
|
|
/// The struct for which `SystemParam` is derived must (currently) have exactly
|
|
/// two lifetime parameters.
|
|
/// The first is the lifetime of the world, and the second the lifetime
|
|
/// of the parameter's state.
|
|
///
|
|
/// ## Attributes
|
|
///
|
|
/// `#[system_param(ignore)]`:
|
|
/// Can be added to any field in the struct. Fields decorated with this attribute
|
|
/// will be created with the default value upon realisation.
|
|
/// This is most useful for `PhantomData` fields, to ensure that the required lifetimes are
|
|
/// used, as shown in the example.
|
|
///
|
|
/// # Example
|
|
///
|
|
/// ```
|
|
/// # use bevy_ecs::prelude::*;
|
|
/// # #[derive(Resource)]
|
|
/// # struct SomeResource;
|
|
/// use std::marker::PhantomData;
|
|
/// use bevy_ecs::system::SystemParam;
|
|
///
|
|
/// #[derive(SystemParam)]
|
|
/// struct MyParam<'w, 's> {
|
|
/// foo: Res<'w, SomeResource>,
|
|
/// #[system_param(ignore)]
|
|
/// marker: PhantomData<&'s ()>,
|
|
/// }
|
|
///
|
|
/// fn my_system(param: MyParam) {
|
|
/// // Access the resource through `param.foo`
|
|
/// }
|
|
///
|
|
/// # bevy_ecs::system::assert_is_system(my_system);
|
|
/// ```
|
|
///
|
|
/// # Generic `SystemParam`s
|
|
///
|
|
/// When using the derive macro, you may see an error in the form of:
|
|
///
|
|
/// ```text
|
|
/// expected ... [ParamType]
|
|
/// found associated type `<<[ParamType] as SystemParam>::Fetch as SystemParamFetch<'_, '_>>::Item`
|
|
/// ```
|
|
/// where `[ParamType]` is the type of one of your fields.
|
|
/// To solve this error, you can wrap the field of type `[ParamType]` with [`StaticSystemParam`]
|
|
/// (i.e. `StaticSystemParam<[ParamType]>`).
|
|
///
|
|
/// ## Details
|
|
///
|
|
/// The derive macro requires that the [`SystemParam`] implementation of
|
|
/// each field `F`'s [`Fetch`](`SystemParam::Fetch`)'s [`Item`](`SystemParamFetch::Item`) is itself `F`
|
|
/// (ignoring lifetimes for simplicity).
|
|
/// This assumption is due to type inference reasons, so that the derived [`SystemParam`] can be
|
|
/// used as an argument to a function system.
|
|
/// If the compiler cannot validate this property for `[ParamType]`, it will error in the form shown above.
|
|
///
|
|
/// This will most commonly occur when working with `SystemParam`s generically, as the requirement
|
|
/// has not been proven to the compiler.
|
|
pub trait SystemParam: Sized {
|
|
type Fetch: for<'w, 's> SystemParamFetch<'w, 's>;
|
|
}
|
|
|
|
pub type SystemParamItem<'w, 's, P> = <<P as SystemParam>::Fetch as SystemParamFetch<'w, 's>>::Item;
|
|
|
|
/// The state of a [`SystemParam`].
|
|
///
|
|
/// # Safety
|
|
///
|
|
/// It is the implementor's responsibility to ensure `system_meta` is populated with the _exact_
|
|
/// [`World`] access used by the [`SystemParamState`] (and associated [`SystemParamFetch`]).
|
|
/// Additionally, it is the implementor's responsibility to ensure there is no
|
|
/// conflicting access across all [`SystemParam`]'s.
|
|
pub unsafe trait SystemParamState: Send + Sync + 'static {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self;
|
|
#[inline]
|
|
fn new_archetype(&mut self, _archetype: &Archetype, _system_meta: &mut SystemMeta) {}
|
|
#[inline]
|
|
fn apply(&mut self, _world: &mut World) {}
|
|
}
|
|
|
|
/// A [`SystemParamFetch`] that only reads a given [`World`].
|
|
///
|
|
/// # Safety
|
|
/// This must only be implemented for [`SystemParamFetch`] impls that exclusively read the World passed in to [`SystemParamFetch::get_param`]
|
|
pub unsafe trait ReadOnlySystemParamFetch {}
|
|
|
|
pub trait SystemParamFetch<'world, 'state>: SystemParamState {
|
|
type Item: SystemParam<Fetch = Self>;
|
|
/// # Safety
|
|
///
|
|
/// This call might access any of the input parameters in an unsafe way. Make sure the data
|
|
/// access is safe in the context of the system scheduler.
|
|
unsafe fn get_param(
|
|
state: &'state mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'world World,
|
|
change_tick: u32,
|
|
) -> Self::Item;
|
|
}
|
|
|
|
impl<'w, 's, Q: WorldQuery + 'static, F: ReadOnlyWorldQuery + 'static> SystemParam
|
|
for Query<'w, 's, Q, F>
|
|
{
|
|
type Fetch = QueryState<Q, F>;
|
|
}
|
|
|
|
// SAFETY: QueryState is constrained to read-only fetches, so it only reads World.
|
|
unsafe impl<Q: ReadOnlyWorldQuery, F: ReadOnlyWorldQuery> ReadOnlySystemParamFetch
|
|
for QueryState<Q, F>
|
|
{
|
|
}
|
|
|
|
// SAFETY: Relevant query ComponentId and ArchetypeComponentId access is applied to SystemMeta. If
|
|
// this QueryState conflicts with any prior access, a panic will occur.
|
|
unsafe impl<Q: WorldQuery + 'static, F: ReadOnlyWorldQuery + 'static> SystemParamState
|
|
for QueryState<Q, F>
|
|
{
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
let state = QueryState::new(world);
|
|
assert_component_access_compatibility(
|
|
&system_meta.name,
|
|
std::any::type_name::<Q>(),
|
|
std::any::type_name::<F>(),
|
|
&system_meta.component_access_set,
|
|
&state.component_access,
|
|
world,
|
|
);
|
|
system_meta
|
|
.component_access_set
|
|
.add(state.component_access.clone());
|
|
system_meta
|
|
.archetype_component_access
|
|
.extend(&state.archetype_component_access);
|
|
state
|
|
}
|
|
|
|
fn new_archetype(&mut self, archetype: &Archetype, system_meta: &mut SystemMeta) {
|
|
self.new_archetype(archetype);
|
|
system_meta
|
|
.archetype_component_access
|
|
.extend(&self.archetype_component_access);
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, Q: WorldQuery + 'static, F: ReadOnlyWorldQuery + 'static> SystemParamFetch<'w, 's>
|
|
for QueryState<Q, F>
|
|
{
|
|
type Item = Query<'w, 's, Q, F>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
Query::new(world, state, system_meta.last_change_tick, change_tick)
|
|
}
|
|
}
|
|
|
|
fn assert_component_access_compatibility(
|
|
system_name: &str,
|
|
query_type: &'static str,
|
|
filter_type: &'static str,
|
|
system_access: &FilteredAccessSet<ComponentId>,
|
|
current: &FilteredAccess<ComponentId>,
|
|
world: &World,
|
|
) {
|
|
let mut conflicts = system_access.get_conflicts_single(current);
|
|
if conflicts.is_empty() {
|
|
return;
|
|
}
|
|
let conflicting_components = conflicts
|
|
.drain(..)
|
|
.map(|component_id| world.components.get_info(component_id).unwrap().name())
|
|
.collect::<Vec<&str>>();
|
|
let accesses = conflicting_components.join(", ");
|
|
panic!("error[B0001]: Query<{}, {}> in system {} accesses component(s) {} in a way that conflicts with a previous system parameter. Consider using `Without<T>` to create disjoint Queries or merging conflicting Queries into a `ParamSet`.",
|
|
query_type, filter_type, system_name, accesses);
|
|
}
|
|
|
|
pub struct ParamSet<'w, 's, T: SystemParam> {
|
|
param_states: &'s mut T::Fetch,
|
|
world: &'w World,
|
|
system_meta: SystemMeta,
|
|
change_tick: u32,
|
|
}
|
|
/// The [`SystemParamState`] of [`ParamSet<T::Item>`].
|
|
pub struct ParamSetState<T: for<'w, 's> SystemParamFetch<'w, 's>>(T);
|
|
|
|
impl_param_set!();
|
|
|
|
/// A type that can be inserted into a [`World`] as a singleton.
|
|
///
|
|
/// You can access resource data in systems using the [`Res`] and [`ResMut`] system parameters
|
|
///
|
|
/// Only one resource of each type can be stored in a [`World`] at any given time.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # let mut world = World::default();
|
|
/// # let mut schedule = Schedule::default();
|
|
/// # schedule.add_stage("update", SystemStage::parallel());
|
|
/// # use bevy_ecs::prelude::*;
|
|
/// #[derive(Resource)]
|
|
/// struct MyResource { value: u32 }
|
|
///
|
|
/// world.insert_resource(MyResource { value: 42 });
|
|
///
|
|
/// fn read_resource_system(resource: Res<MyResource>) {
|
|
/// assert_eq!(resource.value, 42);
|
|
/// }
|
|
///
|
|
/// fn write_resource_system(mut resource: ResMut<MyResource>) {
|
|
/// assert_eq!(resource.value, 42);
|
|
/// resource.value = 0;
|
|
/// assert_eq!(resource.value, 0);
|
|
/// }
|
|
/// # schedule.add_system_to_stage("update", read_resource_system.label("first"));
|
|
/// # schedule.add_system_to_stage("update", write_resource_system.after("first"));
|
|
/// # schedule.run_once(&mut world);
|
|
/// ```
|
|
pub trait Resource: Send + Sync + 'static {}
|
|
|
|
/// Shared borrow of a [`Resource`].
|
|
///
|
|
/// See the [`Resource`] documentation for usage.
|
|
///
|
|
/// If you need a unique mutable borrow, use [`ResMut`] instead.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics when used as a [`SystemParameter`](SystemParam) if the resource does not exist.
|
|
///
|
|
/// Use `Option<Res<T>>` instead if the resource might not always exist.
|
|
pub struct Res<'w, T: Resource> {
|
|
value: &'w T,
|
|
ticks: &'w ComponentTicks,
|
|
last_change_tick: u32,
|
|
change_tick: u32,
|
|
}
|
|
|
|
// SAFETY: Res only reads a single World resource
|
|
unsafe impl<T: Resource> ReadOnlySystemParamFetch for ResState<T> {}
|
|
|
|
impl<'w, T: Resource> Debug for Res<'w, T>
|
|
where
|
|
T: Debug,
|
|
{
|
|
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
|
|
f.debug_tuple("Res").field(&self.value).finish()
|
|
}
|
|
}
|
|
|
|
impl<'w, T: Resource> Res<'w, T> {
|
|
/// Returns `true` if the resource was added after the system last ran.
|
|
pub fn is_added(&self) -> bool {
|
|
self.ticks.is_added(self.last_change_tick, self.change_tick)
|
|
}
|
|
|
|
/// Returns `true` if the resource was added or mutably dereferenced after the system last ran.
|
|
pub fn is_changed(&self) -> bool {
|
|
self.ticks
|
|
.is_changed(self.last_change_tick, self.change_tick)
|
|
}
|
|
|
|
pub fn into_inner(self) -> &'w T {
|
|
self.value
|
|
}
|
|
}
|
|
|
|
impl<'w, T: Resource> Deref for Res<'w, T> {
|
|
type Target = T;
|
|
|
|
fn deref(&self) -> &Self::Target {
|
|
self.value
|
|
}
|
|
}
|
|
|
|
impl<'w, T: Resource> AsRef<T> for Res<'w, T> {
|
|
#[inline]
|
|
fn as_ref(&self) -> &T {
|
|
self.deref()
|
|
}
|
|
}
|
|
|
|
impl<'w, T: Resource> From<ResMut<'w, T>> for Res<'w, T> {
|
|
fn from(res: ResMut<'w, T>) -> Self {
|
|
Self {
|
|
value: res.value,
|
|
ticks: res.ticks.component_ticks,
|
|
change_tick: res.ticks.change_tick,
|
|
last_change_tick: res.ticks.last_change_tick,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`Res<T>`].
|
|
#[doc(hidden)]
|
|
pub struct ResState<T> {
|
|
component_id: ComponentId,
|
|
marker: PhantomData<T>,
|
|
}
|
|
|
|
impl<'a, T: Resource> SystemParam for Res<'a, T> {
|
|
type Fetch = ResState<T>;
|
|
}
|
|
|
|
// SAFETY: Res ComponentId and ArchetypeComponentId access is applied to SystemMeta. If this Res
|
|
// conflicts with any prior access, a panic will occur.
|
|
unsafe impl<T: Resource> SystemParamState for ResState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
let component_id = world.initialize_resource::<T>();
|
|
let combined_access = system_meta.component_access_set.combined_access_mut();
|
|
assert!(
|
|
!combined_access.has_write(component_id),
|
|
"error[B0002]: Res<{}> in system {} conflicts with a previous ResMut<{0}> access. Consider removing the duplicate access.",
|
|
std::any::type_name::<T>(),
|
|
system_meta.name,
|
|
);
|
|
combined_access.add_read(component_id);
|
|
|
|
let resource_archetype = world.archetypes.resource();
|
|
let archetype_component_id = resource_archetype
|
|
.get_archetype_component_id(component_id)
|
|
.unwrap();
|
|
system_meta
|
|
.archetype_component_access
|
|
.add_read(archetype_component_id);
|
|
Self {
|
|
component_id,
|
|
marker: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: Resource> SystemParamFetch<'w, 's> for ResState<T> {
|
|
type Item = Res<'w, T>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
let column = world
|
|
.get_populated_resource_column(state.component_id)
|
|
.unwrap_or_else(|| {
|
|
panic!(
|
|
"Resource requested by {} does not exist: {}",
|
|
system_meta.name,
|
|
std::any::type_name::<T>()
|
|
)
|
|
});
|
|
Res {
|
|
value: column.get_data_ptr().deref::<T>(),
|
|
ticks: column.get_ticks_unchecked(0).deref(),
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`Option<Res<T>>`].
|
|
/// See: [`Res<T>`]
|
|
#[doc(hidden)]
|
|
pub struct OptionResState<T>(ResState<T>);
|
|
|
|
impl<'a, T: Resource> SystemParam for Option<Res<'a, T>> {
|
|
type Fetch = OptionResState<T>;
|
|
}
|
|
|
|
// SAFETY: Only reads a single World resource
|
|
unsafe impl<T: Resource> ReadOnlySystemParamFetch for OptionResState<T> {}
|
|
|
|
// SAFETY: this impl defers to `ResState`, which initializes
|
|
// and validates the correct world access
|
|
unsafe impl<T: Resource> SystemParamState for OptionResState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
Self(ResState::init(world, system_meta))
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: Resource> SystemParamFetch<'w, 's> for OptionResState<T> {
|
|
type Item = Option<Res<'w, T>>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
world
|
|
.get_populated_resource_column(state.0.component_id)
|
|
.map(|column| Res {
|
|
value: column.get_data_ptr().deref::<T>(),
|
|
ticks: column.get_ticks_unchecked(0).deref(),
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
})
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`ResMut<T>`].
|
|
#[doc(hidden)]
|
|
pub struct ResMutState<T> {
|
|
component_id: ComponentId,
|
|
marker: PhantomData<T>,
|
|
}
|
|
|
|
impl<'a, T: Resource> SystemParam for ResMut<'a, T> {
|
|
type Fetch = ResMutState<T>;
|
|
}
|
|
|
|
// SAFETY: Res ComponentId and ArchetypeComponentId access is applied to SystemMeta. If this Res
|
|
// conflicts with any prior access, a panic will occur.
|
|
unsafe impl<T: Resource> SystemParamState for ResMutState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
let component_id = world.initialize_resource::<T>();
|
|
let combined_access = system_meta.component_access_set.combined_access_mut();
|
|
if combined_access.has_write(component_id) {
|
|
panic!(
|
|
"error[B0002]: ResMut<{}> in system {} conflicts with a previous ResMut<{0}> access. Consider removing the duplicate access.",
|
|
std::any::type_name::<T>(), system_meta.name);
|
|
} else if combined_access.has_read(component_id) {
|
|
panic!(
|
|
"error[B0002]: ResMut<{}> in system {} conflicts with a previous Res<{0}> access. Consider removing the duplicate access.",
|
|
std::any::type_name::<T>(), system_meta.name);
|
|
}
|
|
combined_access.add_write(component_id);
|
|
|
|
let resource_archetype = world.archetypes.resource();
|
|
let archetype_component_id = resource_archetype
|
|
.get_archetype_component_id(component_id)
|
|
.unwrap();
|
|
system_meta
|
|
.archetype_component_access
|
|
.add_write(archetype_component_id);
|
|
Self {
|
|
component_id,
|
|
marker: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: Resource> SystemParamFetch<'w, 's> for ResMutState<T> {
|
|
type Item = ResMut<'w, T>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
let value = world
|
|
.get_resource_unchecked_mut_with_id(state.component_id)
|
|
.unwrap_or_else(|| {
|
|
panic!(
|
|
"Resource requested by {} does not exist: {}",
|
|
system_meta.name,
|
|
std::any::type_name::<T>()
|
|
)
|
|
});
|
|
ResMut {
|
|
value: value.value,
|
|
ticks: Ticks {
|
|
component_ticks: value.ticks.component_ticks,
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
},
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`Option<ResMut<T>>`].
|
|
/// See: [`ResMut<T>`]
|
|
#[doc(hidden)]
|
|
pub struct OptionResMutState<T>(ResMutState<T>);
|
|
|
|
impl<'a, T: Resource> SystemParam for Option<ResMut<'a, T>> {
|
|
type Fetch = OptionResMutState<T>;
|
|
}
|
|
|
|
// SAFETY: this impl defers to `ResMutState`, which initializes
|
|
// and validates the correct world access
|
|
unsafe impl<T: Resource> SystemParamState for OptionResMutState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
Self(ResMutState::init(world, system_meta))
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: Resource> SystemParamFetch<'w, 's> for OptionResMutState<T> {
|
|
type Item = Option<ResMut<'w, T>>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
world
|
|
.get_resource_unchecked_mut_with_id(state.0.component_id)
|
|
.map(|value| ResMut {
|
|
value: value.value,
|
|
ticks: Ticks {
|
|
component_ticks: value.ticks.component_ticks,
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParam for Commands<'w, 's> {
|
|
type Fetch = CommandQueue;
|
|
}
|
|
|
|
// SAFETY: Commands only accesses internal state
|
|
unsafe impl ReadOnlySystemParamFetch for CommandQueue {}
|
|
|
|
// SAFETY: only local state is accessed
|
|
unsafe impl SystemParamState for CommandQueue {
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Default::default()
|
|
}
|
|
|
|
fn apply(&mut self, world: &mut World) {
|
|
self.apply(world);
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for CommandQueue {
|
|
type Item = Commands<'w, 's>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
Commands::new(state, world)
|
|
}
|
|
}
|
|
|
|
/// SAFETY: only reads world
|
|
unsafe impl ReadOnlySystemParamFetch for WorldState {}
|
|
|
|
/// The [`SystemParamState`] of [`&World`](crate::world::World).
|
|
#[doc(hidden)]
|
|
pub struct WorldState;
|
|
|
|
impl<'w> SystemParam for &'w World {
|
|
type Fetch = WorldState;
|
|
}
|
|
|
|
// SAFETY: `read_all` access is set and conflicts result in a panic
|
|
unsafe impl SystemParamState for WorldState {
|
|
fn init(_world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
let mut access = Access::default();
|
|
access.read_all();
|
|
if !system_meta
|
|
.archetype_component_access
|
|
.is_compatible(&access)
|
|
{
|
|
panic!("&World conflicts with a previous mutable system parameter. Allowing this would break Rust's mutability rules");
|
|
}
|
|
system_meta.archetype_component_access.extend(&access);
|
|
|
|
let mut filtered_access = FilteredAccess::default();
|
|
|
|
filtered_access.read_all();
|
|
if !system_meta
|
|
.component_access_set
|
|
.get_conflicts_single(&filtered_access)
|
|
.is_empty()
|
|
{
|
|
panic!("&World conflicts with a previous mutable system parameter. Allowing this would break Rust's mutability rules");
|
|
}
|
|
system_meta.component_access_set.add(filtered_access);
|
|
|
|
WorldState
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for WorldState {
|
|
type Item = &'w World;
|
|
unsafe fn get_param(
|
|
_state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
world
|
|
}
|
|
}
|
|
|
|
/// A system local [`SystemParam`].
|
|
///
|
|
/// A local may only be accessed by the system itself and is therefore not visible to other systems.
|
|
/// If two or more systems specify the same local type each will have their own unique local.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # use bevy_ecs::prelude::*;
|
|
/// # let world = &mut World::default();
|
|
/// fn write_to_local(mut local: Local<usize>) {
|
|
/// *local = 42;
|
|
/// }
|
|
/// fn read_from_local(local: Local<usize>) -> usize {
|
|
/// *local
|
|
/// }
|
|
/// let mut write_system = IntoSystem::into_system(write_to_local);
|
|
/// let mut read_system = IntoSystem::into_system(read_from_local);
|
|
/// write_system.initialize(world);
|
|
/// read_system.initialize(world);
|
|
///
|
|
/// assert_eq!(read_system.run((), world), 0);
|
|
/// write_system.run((), world);
|
|
/// // Note how the read local is still 0 due to the locals not being shared.
|
|
/// assert_eq!(read_system.run((), world), 0);
|
|
/// ```
|
|
///
|
|
/// N.B. A [`Local`]s value cannot be read or written to outside of the containing system.
|
|
/// To add configuration to a system, convert a capturing closure into the system instead:
|
|
///
|
|
/// ```
|
|
/// # use bevy_ecs::prelude::*;
|
|
/// # use bevy_ecs::system::assert_is_system;
|
|
/// struct Config(u32);
|
|
/// #[derive(Resource)]
|
|
/// struct Myu32Wrapper(u32);
|
|
/// fn reset_to_system(value: Config) -> impl FnMut(ResMut<Myu32Wrapper>) {
|
|
/// move |mut val| val.0 = value.0
|
|
/// }
|
|
///
|
|
/// // .add_system(reset_to_system(my_config))
|
|
/// # assert_is_system(reset_to_system(Config(10)));
|
|
/// ```
|
|
pub struct Local<'a, T: FromWorld + Send + 'static>(pub(crate) &'a mut T);
|
|
|
|
// SAFETY: Local only accesses internal state
|
|
unsafe impl<T: Send + 'static> ReadOnlySystemParamFetch for LocalState<T> {}
|
|
|
|
impl<'a, T: FromWorld + Send + Sync + 'static> Debug for Local<'a, T>
|
|
where
|
|
T: Debug,
|
|
{
|
|
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
|
|
f.debug_tuple("Local").field(&self.0).finish()
|
|
}
|
|
}
|
|
|
|
impl<'a, T: FromWorld + Send + Sync + 'static> Deref for Local<'a, T> {
|
|
type Target = T;
|
|
|
|
#[inline]
|
|
fn deref(&self) -> &Self::Target {
|
|
self.0
|
|
}
|
|
}
|
|
|
|
impl<'a, T: FromWorld + Send + Sync + 'static> DerefMut for Local<'a, T> {
|
|
#[inline]
|
|
fn deref_mut(&mut self) -> &mut Self::Target {
|
|
self.0
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`Local<T>`].
|
|
#[doc(hidden)]
|
|
pub struct LocalState<T: Send + 'static>(pub(crate) SyncCell<T>);
|
|
|
|
impl<'a, T: FromWorld + Send + 'static> SystemParam for Local<'a, T> {
|
|
type Fetch = LocalState<T>;
|
|
}
|
|
|
|
// SAFETY: only local state is accessed
|
|
unsafe impl<T: FromWorld + Send + 'static> SystemParamState for LocalState<T> {
|
|
fn init(world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self(SyncCell::new(T::from_world(world)))
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: FromWorld + Send + 'static> SystemParamFetch<'w, 's> for LocalState<T> {
|
|
type Item = Local<'s, T>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
_world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
Local(state.0.get())
|
|
}
|
|
}
|
|
|
|
/// A [`SystemParam`] that grants access to the entities that had their `T` [`Component`] removed.
|
|
///
|
|
/// Note that this does not allow you to see which data existed before removal.
|
|
/// If you need this, you will need to track the component data value on your own,
|
|
/// using a regularly scheduled system that requests `Query<(Entity, &T), Changed<T>>`
|
|
/// and stores the data somewhere safe to later cross-reference.
|
|
///
|
|
/// If you are using `bevy_ecs` as a standalone crate,
|
|
/// note that the `RemovedComponents` list will not be automatically cleared for you,
|
|
/// and will need to be manually flushed using [`World::clear_trackers`]
|
|
///
|
|
/// For users of `bevy` itself, this is automatically done in a system added by `MinimalPlugins`
|
|
/// or `DefaultPlugins` at the end of each pass of the game loop during the `CoreStage::Last`
|
|
/// stage. As such `RemovedComponents` systems should be scheduled after the stage where
|
|
/// removal occurs but before `CoreStage::Last`.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// Basic usage:
|
|
///
|
|
/// ```
|
|
/// # use bevy_ecs::component::Component;
|
|
/// # use bevy_ecs::system::IntoSystem;
|
|
/// # use bevy_ecs::system::RemovedComponents;
|
|
/// #
|
|
/// # #[derive(Component)]
|
|
/// # struct MyComponent;
|
|
///
|
|
/// fn react_on_removal(removed: RemovedComponents<MyComponent>) {
|
|
/// removed.iter().for_each(|removed_entity| println!("{:?}", removed_entity));
|
|
/// }
|
|
///
|
|
/// # bevy_ecs::system::assert_is_system(react_on_removal);
|
|
/// ```
|
|
pub struct RemovedComponents<'a, T: Component> {
|
|
world: &'a World,
|
|
component_id: ComponentId,
|
|
marker: PhantomData<T>,
|
|
}
|
|
|
|
impl<'a, T: Component> RemovedComponents<'a, T> {
|
|
/// Returns an iterator over the entities that had their `T` [`Component`] removed.
|
|
pub fn iter(&self) -> std::iter::Cloned<std::slice::Iter<'_, Entity>> {
|
|
self.world.removed_with_id(self.component_id)
|
|
}
|
|
}
|
|
|
|
impl<'a, T: Component> IntoIterator for &'a RemovedComponents<'a, T> {
|
|
type Item = Entity;
|
|
type IntoIter = std::iter::Cloned<std::slice::Iter<'a, Entity>>;
|
|
|
|
fn into_iter(self) -> Self::IntoIter {
|
|
self.iter()
|
|
}
|
|
}
|
|
|
|
// SAFETY: Only reads World components
|
|
unsafe impl<T: Component> ReadOnlySystemParamFetch for RemovedComponentsState<T> {}
|
|
|
|
/// The [`SystemParamState`] of [`RemovedComponents<T>`].
|
|
#[doc(hidden)]
|
|
pub struct RemovedComponentsState<T> {
|
|
component_id: ComponentId,
|
|
marker: PhantomData<T>,
|
|
}
|
|
|
|
impl<'a, T: Component> SystemParam for RemovedComponents<'a, T> {
|
|
type Fetch = RemovedComponentsState<T>;
|
|
}
|
|
|
|
// SAFETY: no component access. removed component entity collections can be read in parallel and are
|
|
// never mutably borrowed during system execution
|
|
unsafe impl<T: Component> SystemParamState for RemovedComponentsState<T> {
|
|
fn init(world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self {
|
|
component_id: world.init_component::<T>(),
|
|
marker: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: Component> SystemParamFetch<'w, 's> for RemovedComponentsState<T> {
|
|
type Item = RemovedComponents<'w, T>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
RemovedComponents {
|
|
world,
|
|
component_id: state.component_id,
|
|
marker: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Shared borrow of a non-[`Send`] resource.
|
|
///
|
|
/// Only `Send` resources may be accessed with the [`Res`] [`SystemParam`]. In case that the
|
|
/// resource does not implement `Send`, this `SystemParam` wrapper can be used. This will instruct
|
|
/// the scheduler to instead run the system on the main thread so that it doesn't send the resource
|
|
/// over to another thread.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics when used as a `SystemParameter` if the resource does not exist.
|
|
///
|
|
/// Use `Option<NonSend<T>>` instead if the resource might not always exist.
|
|
pub struct NonSend<'w, T: 'static> {
|
|
pub(crate) value: &'w T,
|
|
ticks: ComponentTicks,
|
|
last_change_tick: u32,
|
|
change_tick: u32,
|
|
}
|
|
|
|
// SAFETY: Only reads a single World non-send resource
|
|
unsafe impl<T> ReadOnlySystemParamFetch for NonSendState<T> {}
|
|
|
|
impl<'w, T> Debug for NonSend<'w, T>
|
|
where
|
|
T: Debug,
|
|
{
|
|
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
|
|
f.debug_tuple("NonSend").field(&self.value).finish()
|
|
}
|
|
}
|
|
|
|
impl<'w, T: 'static> NonSend<'w, T> {
|
|
/// Returns `true` if the resource was added after the system last ran.
|
|
pub fn is_added(&self) -> bool {
|
|
self.ticks.is_added(self.last_change_tick, self.change_tick)
|
|
}
|
|
|
|
/// Returns `true` if the resource was added or mutably dereferenced after the system last ran.
|
|
pub fn is_changed(&self) -> bool {
|
|
self.ticks
|
|
.is_changed(self.last_change_tick, self.change_tick)
|
|
}
|
|
}
|
|
|
|
impl<'w, T> Deref for NonSend<'w, T> {
|
|
type Target = T;
|
|
|
|
fn deref(&self) -> &Self::Target {
|
|
self.value
|
|
}
|
|
}
|
|
impl<'a, T> From<NonSendMut<'a, T>> for NonSend<'a, T> {
|
|
fn from(nsm: NonSendMut<'a, T>) -> Self {
|
|
Self {
|
|
value: nsm.value,
|
|
ticks: nsm.ticks.component_ticks.to_owned(),
|
|
change_tick: nsm.ticks.change_tick,
|
|
last_change_tick: nsm.ticks.last_change_tick,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`NonSend<T>`].
|
|
#[doc(hidden)]
|
|
pub struct NonSendState<T> {
|
|
component_id: ComponentId,
|
|
marker: PhantomData<fn() -> T>,
|
|
}
|
|
|
|
impl<'a, T: 'static> SystemParam for NonSend<'a, T> {
|
|
type Fetch = NonSendState<T>;
|
|
}
|
|
|
|
// SAFETY: NonSendComponentId and ArchetypeComponentId access is applied to SystemMeta. If this
|
|
// NonSend conflicts with any prior access, a panic will occur.
|
|
unsafe impl<T: 'static> SystemParamState for NonSendState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
system_meta.set_non_send();
|
|
|
|
let component_id = world.initialize_non_send_resource::<T>();
|
|
let combined_access = system_meta.component_access_set.combined_access_mut();
|
|
assert!(
|
|
!combined_access.has_write(component_id),
|
|
"error[B0002]: NonSend<{}> in system {} conflicts with a previous mutable resource access ({0}). Consider removing the duplicate access.",
|
|
std::any::type_name::<T>(),
|
|
system_meta.name,
|
|
);
|
|
combined_access.add_read(component_id);
|
|
|
|
let resource_archetype = world.archetypes.resource();
|
|
let archetype_component_id = resource_archetype
|
|
.get_archetype_component_id(component_id)
|
|
.unwrap();
|
|
system_meta
|
|
.archetype_component_access
|
|
.add_read(archetype_component_id);
|
|
Self {
|
|
component_id,
|
|
marker: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: 'static> SystemParamFetch<'w, 's> for NonSendState<T> {
|
|
type Item = NonSend<'w, T>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
world.validate_non_send_access::<T>();
|
|
let column = world
|
|
.get_populated_resource_column(state.component_id)
|
|
.unwrap_or_else(|| {
|
|
panic!(
|
|
"Non-send resource requested by {} does not exist: {}",
|
|
system_meta.name,
|
|
std::any::type_name::<T>()
|
|
)
|
|
});
|
|
|
|
NonSend {
|
|
value: column.get_data_ptr().deref::<T>(),
|
|
ticks: column.get_ticks_unchecked(0).read(),
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`Option<NonSend<T>>`].
|
|
/// See: [`NonSend<T>`]
|
|
#[doc(hidden)]
|
|
pub struct OptionNonSendState<T>(NonSendState<T>);
|
|
|
|
impl<'w, T: 'static> SystemParam for Option<NonSend<'w, T>> {
|
|
type Fetch = OptionNonSendState<T>;
|
|
}
|
|
|
|
// SAFETY: Only reads a single non-send resource
|
|
unsafe impl<T: 'static> ReadOnlySystemParamFetch for OptionNonSendState<T> {}
|
|
|
|
// SAFETY: this impl defers to `NonSendState`, which initializes
|
|
// and validates the correct world access
|
|
unsafe impl<T: 'static> SystemParamState for OptionNonSendState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
Self(NonSendState::init(world, system_meta))
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: 'static> SystemParamFetch<'w, 's> for OptionNonSendState<T> {
|
|
type Item = Option<NonSend<'w, T>>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
world.validate_non_send_access::<T>();
|
|
world
|
|
.get_populated_resource_column(state.0.component_id)
|
|
.map(|column| NonSend {
|
|
value: column.get_data_ptr().deref::<T>(),
|
|
ticks: column.get_ticks_unchecked(0).read(),
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
})
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`NonSendMut<T>`].
|
|
#[doc(hidden)]
|
|
pub struct NonSendMutState<T> {
|
|
component_id: ComponentId,
|
|
marker: PhantomData<fn() -> T>,
|
|
}
|
|
|
|
impl<'a, T: 'static> SystemParam for NonSendMut<'a, T> {
|
|
type Fetch = NonSendMutState<T>;
|
|
}
|
|
|
|
// SAFETY: NonSendMut ComponentId and ArchetypeComponentId access is applied to SystemMeta. If this
|
|
// NonSendMut conflicts with any prior access, a panic will occur.
|
|
unsafe impl<T: 'static> SystemParamState for NonSendMutState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
system_meta.set_non_send();
|
|
|
|
let component_id = world.initialize_non_send_resource::<T>();
|
|
let combined_access = system_meta.component_access_set.combined_access_mut();
|
|
if combined_access.has_write(component_id) {
|
|
panic!(
|
|
"error[B0002]: NonSendMut<{}> in system {} conflicts with a previous mutable resource access ({0}). Consider removing the duplicate access.",
|
|
std::any::type_name::<T>(), system_meta.name);
|
|
} else if combined_access.has_read(component_id) {
|
|
panic!(
|
|
"error[B0002]: NonSendMut<{}> in system {} conflicts with a previous immutable resource access ({0}). Consider removing the duplicate access.",
|
|
std::any::type_name::<T>(), system_meta.name);
|
|
}
|
|
combined_access.add_write(component_id);
|
|
|
|
let resource_archetype = world.archetypes.resource();
|
|
let archetype_component_id = resource_archetype
|
|
.get_archetype_component_id(component_id)
|
|
.unwrap();
|
|
system_meta
|
|
.archetype_component_access
|
|
.add_write(archetype_component_id);
|
|
Self {
|
|
component_id,
|
|
marker: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: 'static> SystemParamFetch<'w, 's> for NonSendMutState<T> {
|
|
type Item = NonSendMut<'w, T>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
world.validate_non_send_access::<T>();
|
|
let column = world
|
|
.get_populated_resource_column(state.component_id)
|
|
.unwrap_or_else(|| {
|
|
panic!(
|
|
"Non-send resource requested by {} does not exist: {}",
|
|
system_meta.name,
|
|
std::any::type_name::<T>()
|
|
)
|
|
});
|
|
NonSendMut {
|
|
value: column.get_data_ptr().assert_unique().deref_mut::<T>(),
|
|
ticks: Ticks {
|
|
component_ticks: column.get_ticks_unchecked(0).deref_mut(),
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
},
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`Option<NonSendMut<T>>`].
|
|
/// See: [`NonSendMut<T>`]
|
|
#[doc(hidden)]
|
|
pub struct OptionNonSendMutState<T>(NonSendMutState<T>);
|
|
|
|
impl<'a, T: 'static> SystemParam for Option<NonSendMut<'a, T>> {
|
|
type Fetch = OptionNonSendMutState<T>;
|
|
}
|
|
|
|
// SAFETY: this impl defers to `NonSendMutState`, which initializes
|
|
// and validates the correct world access
|
|
unsafe impl<T: 'static> SystemParamState for OptionNonSendMutState<T> {
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
Self(NonSendMutState::init(world, system_meta))
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, T: 'static> SystemParamFetch<'w, 's> for OptionNonSendMutState<T> {
|
|
type Item = Option<NonSendMut<'w, T>>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
world.validate_non_send_access::<T>();
|
|
world
|
|
.get_populated_resource_column(state.0.component_id)
|
|
.map(|column| NonSendMut {
|
|
value: column.get_data_ptr().assert_unique().deref_mut::<T>(),
|
|
ticks: Ticks {
|
|
component_ticks: column.get_ticks_unchecked(0).deref_mut(),
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
|
|
impl<'a> SystemParam for &'a Archetypes {
|
|
type Fetch = ArchetypesState;
|
|
}
|
|
|
|
// SAFETY: Only reads World archetypes
|
|
unsafe impl ReadOnlySystemParamFetch for ArchetypesState {}
|
|
|
|
/// The [`SystemParamState`] of [`Archetypes`].
|
|
#[doc(hidden)]
|
|
pub struct ArchetypesState;
|
|
|
|
// SAFETY: no component value access
|
|
unsafe impl SystemParamState for ArchetypesState {
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for ArchetypesState {
|
|
type Item = &'w Archetypes;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
_state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
world.archetypes()
|
|
}
|
|
}
|
|
|
|
impl<'a> SystemParam for &'a Components {
|
|
type Fetch = ComponentsState;
|
|
}
|
|
|
|
// SAFETY: Only reads World components
|
|
unsafe impl ReadOnlySystemParamFetch for ComponentsState {}
|
|
|
|
/// The [`SystemParamState`] of [`Components`].
|
|
#[doc(hidden)]
|
|
pub struct ComponentsState;
|
|
|
|
// SAFETY: no component value access
|
|
unsafe impl SystemParamState for ComponentsState {
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for ComponentsState {
|
|
type Item = &'w Components;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
_state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
world.components()
|
|
}
|
|
}
|
|
|
|
impl<'a> SystemParam for &'a Entities {
|
|
type Fetch = EntitiesState;
|
|
}
|
|
|
|
// SAFETY: Only reads World entities
|
|
unsafe impl ReadOnlySystemParamFetch for EntitiesState {}
|
|
|
|
/// The [`SystemParamState`] of [`Entities`].
|
|
#[doc(hidden)]
|
|
pub struct EntitiesState;
|
|
|
|
// SAFETY: no component value access
|
|
unsafe impl SystemParamState for EntitiesState {
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for EntitiesState {
|
|
type Item = &'w Entities;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
_state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
world.entities()
|
|
}
|
|
}
|
|
|
|
impl<'a> SystemParam for &'a Bundles {
|
|
type Fetch = BundlesState;
|
|
}
|
|
|
|
// SAFETY: Only reads World bundles
|
|
unsafe impl ReadOnlySystemParamFetch for BundlesState {}
|
|
|
|
/// The [`SystemParamState`] of [`Bundles`].
|
|
#[doc(hidden)]
|
|
pub struct BundlesState;
|
|
|
|
// SAFETY: no component value access
|
|
unsafe impl SystemParamState for BundlesState {
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for BundlesState {
|
|
type Item = &'w Bundles;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
_state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
world.bundles()
|
|
}
|
|
}
|
|
|
|
/// A [`SystemParam`] that reads the previous and current change ticks of the system.
|
|
///
|
|
/// A system's change ticks are updated each time it runs:
|
|
/// - `last_change_tick` copies the previous value of `change_tick`
|
|
/// - `change_tick` copies the current value of [`World::read_change_tick`]
|
|
///
|
|
/// Component change ticks that are more recent than `last_change_tick` will be detected by the system.
|
|
/// Those can be read by calling [`last_changed`](crate::change_detection::DetectChanges::last_changed)
|
|
/// on a [`Mut<T>`](crate::change_detection::Mut) or [`ResMut<T>`](crate::change_detection::ResMut).
|
|
#[derive(Debug)]
|
|
pub struct SystemChangeTick {
|
|
last_change_tick: u32,
|
|
change_tick: u32,
|
|
}
|
|
|
|
impl SystemChangeTick {
|
|
/// Returns the current [`World`] change tick seen by the system.
|
|
#[inline]
|
|
pub fn change_tick(&self) -> u32 {
|
|
self.change_tick
|
|
}
|
|
|
|
/// Returns the [`World`] change tick seen by the system the previous time it ran.
|
|
#[inline]
|
|
pub fn last_change_tick(&self) -> u32 {
|
|
self.last_change_tick
|
|
}
|
|
}
|
|
|
|
// SAFETY: Only reads internal system state
|
|
unsafe impl ReadOnlySystemParamFetch for SystemChangeTickState {}
|
|
|
|
impl SystemParam for SystemChangeTick {
|
|
type Fetch = SystemChangeTickState;
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`SystemChangeTick`].
|
|
#[doc(hidden)]
|
|
pub struct SystemChangeTickState {}
|
|
|
|
// SAFETY: `SystemParamTickState` doesn't require any world access
|
|
unsafe impl SystemParamState for SystemChangeTickState {
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
Self {}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for SystemChangeTickState {
|
|
type Item = SystemChangeTick;
|
|
|
|
unsafe fn get_param(
|
|
_state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
_world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
SystemChangeTick {
|
|
last_change_tick: system_meta.last_change_tick,
|
|
change_tick,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Name of the system that corresponds to this [`crate::system::SystemState`].
|
|
///
|
|
/// This is not a reliable identifier, it is more so useful for debugging
|
|
/// purposes of finding where a system parameter is being used incorrectly.
|
|
pub struct SystemName<'s> {
|
|
name: &'s str,
|
|
}
|
|
|
|
impl<'s> SystemName<'s> {
|
|
pub fn name(&self) -> &str {
|
|
self.name
|
|
}
|
|
}
|
|
|
|
impl<'s> Deref for SystemName<'s> {
|
|
type Target = str;
|
|
fn deref(&self) -> &Self::Target {
|
|
self.name()
|
|
}
|
|
}
|
|
|
|
impl<'s> AsRef<str> for SystemName<'s> {
|
|
fn as_ref(&self) -> &str {
|
|
self.name()
|
|
}
|
|
}
|
|
|
|
impl<'s> From<SystemName<'s>> for &'s str {
|
|
fn from(name: SystemName<'s>) -> &'s str {
|
|
name.name
|
|
}
|
|
}
|
|
|
|
impl<'s> std::fmt::Debug for SystemName<'s> {
|
|
#[inline(always)]
|
|
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
|
|
f.debug_tuple("SystemName").field(&self.name()).finish()
|
|
}
|
|
}
|
|
|
|
impl<'s> std::fmt::Display for SystemName<'s> {
|
|
#[inline(always)]
|
|
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
|
|
std::fmt::Display::fmt(&self.name(), f)
|
|
}
|
|
}
|
|
|
|
impl<'s> SystemParam for SystemName<'s> {
|
|
type Fetch = SystemNameState;
|
|
}
|
|
|
|
// SAFETY: Only reads internal system state
|
|
unsafe impl ReadOnlySystemParamFetch for SystemNameState {}
|
|
|
|
/// The [`SystemParamState`] of [`SystemName`].
|
|
#[doc(hidden)]
|
|
pub struct SystemNameState {
|
|
name: Cow<'static, str>,
|
|
}
|
|
|
|
// SAFETY: no component value access
|
|
unsafe impl SystemParamState for SystemNameState {
|
|
fn init(_world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
Self {
|
|
name: system_meta.name.clone(),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'w, 's> SystemParamFetch<'w, 's> for SystemNameState {
|
|
type Item = SystemName<'s>;
|
|
|
|
#[inline]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
_system_meta: &SystemMeta,
|
|
_world: &'w World,
|
|
_change_tick: u32,
|
|
) -> Self::Item {
|
|
SystemName {
|
|
name: state.name.as_ref(),
|
|
}
|
|
}
|
|
}
|
|
|
|
macro_rules! impl_system_param_tuple {
|
|
($($param: ident),*) => {
|
|
impl<$($param: SystemParam),*> SystemParam for ($($param,)*) {
|
|
type Fetch = ($($param::Fetch,)*);
|
|
}
|
|
|
|
// SAFETY: tuple consists only of ReadOnlySystemParamFetches
|
|
unsafe impl<$($param: ReadOnlySystemParamFetch),*> ReadOnlySystemParamFetch for ($($param,)*) {}
|
|
|
|
#[allow(unused_variables)]
|
|
#[allow(non_snake_case)]
|
|
impl<'w, 's, $($param: SystemParamFetch<'w, 's>),*> SystemParamFetch<'w, 's> for ($($param,)*) {
|
|
type Item = ($($param::Item,)*);
|
|
|
|
#[inline]
|
|
#[allow(clippy::unused_unit)]
|
|
unsafe fn get_param(
|
|
state: &'s mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'w World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
|
|
let ($($param,)*) = state;
|
|
($($param::get_param($param, system_meta, world, change_tick),)*)
|
|
}
|
|
}
|
|
|
|
// SAFETY: implementors of each `SystemParamState` in the tuple have validated their impls
|
|
#[allow(clippy::undocumented_unsafe_blocks)] // false positive by clippy
|
|
#[allow(non_snake_case)]
|
|
unsafe impl<$($param: SystemParamState),*> SystemParamState for ($($param,)*) {
|
|
#[inline]
|
|
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self {
|
|
(($($param::init(_world, _system_meta),)*))
|
|
}
|
|
|
|
#[inline]
|
|
fn new_archetype(&mut self, _archetype: &Archetype, _system_meta: &mut SystemMeta) {
|
|
let ($($param,)*) = self;
|
|
$($param.new_archetype(_archetype, _system_meta);)*
|
|
}
|
|
|
|
#[inline]
|
|
fn apply(&mut self, _world: &mut World) {
|
|
let ($($param,)*) = self;
|
|
$($param.apply(_world);)*
|
|
}
|
|
}
|
|
};
|
|
}
|
|
|
|
all_tuples!(impl_system_param_tuple, 0, 16, P);
|
|
|
|
pub mod lifetimeless {
|
|
pub type SQuery<Q, F = ()> = super::Query<'static, 'static, Q, F>;
|
|
pub type Read<T> = &'static T;
|
|
pub type Write<T> = &'static mut T;
|
|
pub type SRes<T> = super::Res<'static, T>;
|
|
pub type SResMut<T> = super::ResMut<'static, T>;
|
|
pub type SCommands = crate::system::Commands<'static, 'static>;
|
|
}
|
|
|
|
/// A helper for using system parameters in generic contexts
|
|
///
|
|
/// This type is a [`SystemParam`] adapter which always has
|
|
/// `Self::Fetch::Item == Self` (ignoring lifetimes for brevity),
|
|
/// no matter the argument [`SystemParam`] (`P`) (other than
|
|
/// that `P` must be `'static`)
|
|
///
|
|
/// This makes it useful for having arbitrary [`SystemParam`] type arguments
|
|
/// to function systems, or for generic types using the [`derive@SystemParam`]
|
|
/// derive:
|
|
///
|
|
/// ```
|
|
/// # use bevy_ecs::prelude::*;
|
|
/// use bevy_ecs::system::{SystemParam, StaticSystemParam};
|
|
/// #[derive(SystemParam)]
|
|
/// struct GenericParam<'w,'s, T: SystemParam + 'static> {
|
|
/// field: StaticSystemParam<'w, 's, T>,
|
|
/// }
|
|
/// fn do_thing_generically<T: SystemParam + 'static>(t: StaticSystemParam<T>) {}
|
|
///
|
|
/// fn check_always_is_system<T: SystemParam + 'static>(){
|
|
/// bevy_ecs::system::assert_is_system(do_thing_generically::<T>);
|
|
/// }
|
|
/// ```
|
|
/// Note that in a real case you'd generally want
|
|
/// additional bounds on `P`, for your use of the parameter
|
|
/// to have a reason to be generic.
|
|
///
|
|
/// For example, using this would allow a type to be generic over
|
|
/// whether a resource is accessed mutably or not, with
|
|
/// impls being bounded on [`P: Deref<Target=MyType>`](Deref), and
|
|
/// [`P: DerefMut<Target=MyType>`](DerefMut) depending on whether the
|
|
/// method requires mutable access or not.
|
|
///
|
|
/// The method which doesn't use this type will not compile:
|
|
/// ```compile_fail
|
|
/// # use bevy_ecs::prelude::*;
|
|
/// # use bevy_ecs::system::{SystemParam, StaticSystemParam};
|
|
///
|
|
/// fn do_thing_generically<T: SystemParam + 'static>(t: T) {}
|
|
///
|
|
/// #[derive(SystemParam)]
|
|
/// struct GenericParam<'w,'s, T: SystemParam> {
|
|
/// field: T,
|
|
/// #[system_param(ignore)]
|
|
/// // Use the lifetimes, as the `SystemParam` derive requires them
|
|
/// phantom: core::marker::PhantomData<&'w &'s ()>
|
|
/// }
|
|
/// # fn check_always_is_system<T: SystemParam + 'static>(){
|
|
/// # bevy_ecs::system::assert_is_system(do_thing_generically::<T>);
|
|
/// # }
|
|
/// ```
|
|
///
|
|
pub struct StaticSystemParam<'w, 's, P: SystemParam>(SystemParamItem<'w, 's, P>);
|
|
|
|
impl<'w, 's, P: SystemParam> Deref for StaticSystemParam<'w, 's, P> {
|
|
type Target = SystemParamItem<'w, 's, P>;
|
|
|
|
fn deref(&self) -> &Self::Target {
|
|
&self.0
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, P: SystemParam> DerefMut for StaticSystemParam<'w, 's, P> {
|
|
fn deref_mut(&mut self) -> &mut Self::Target {
|
|
&mut self.0
|
|
}
|
|
}
|
|
|
|
impl<'w, 's, P: SystemParam> StaticSystemParam<'w, 's, P> {
|
|
/// Get the value of the parameter
|
|
pub fn into_inner(self) -> SystemParamItem<'w, 's, P> {
|
|
self.0
|
|
}
|
|
}
|
|
|
|
/// The [`SystemParamState`] of [`StaticSystemParam`].
|
|
#[doc(hidden)]
|
|
pub struct StaticSystemParamState<S, P>(S, PhantomData<fn() -> P>);
|
|
|
|
// SAFETY: This doesn't add any more reads, and the delegated fetch confirms it
|
|
unsafe impl<S: ReadOnlySystemParamFetch, P> ReadOnlySystemParamFetch
|
|
for StaticSystemParamState<S, P>
|
|
{
|
|
}
|
|
|
|
impl<'world, 'state, P: SystemParam + 'static> SystemParam
|
|
for StaticSystemParam<'world, 'state, P>
|
|
{
|
|
type Fetch = StaticSystemParamState<P::Fetch, P>;
|
|
}
|
|
|
|
impl<'world, 'state, S: SystemParamFetch<'world, 'state>, P: SystemParam + 'static>
|
|
SystemParamFetch<'world, 'state> for StaticSystemParamState<S, P>
|
|
where
|
|
P: SystemParam<Fetch = S>,
|
|
{
|
|
type Item = StaticSystemParam<'world, 'state, P>;
|
|
|
|
unsafe fn get_param(
|
|
state: &'state mut Self,
|
|
system_meta: &SystemMeta,
|
|
world: &'world World,
|
|
change_tick: u32,
|
|
) -> Self::Item {
|
|
// SAFETY: We properly delegate SystemParamState
|
|
StaticSystemParam(S::get_param(&mut state.0, system_meta, world, change_tick))
|
|
}
|
|
}
|
|
|
|
// SAFETY: all methods are just delegated to `S`'s `SystemParamState` implementation
|
|
unsafe impl<S: SystemParamState, P: SystemParam + 'static> SystemParamState
|
|
for StaticSystemParamState<S, P>
|
|
{
|
|
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self {
|
|
Self(S::init(world, system_meta), PhantomData)
|
|
}
|
|
|
|
fn new_archetype(&mut self, archetype: &Archetype, system_meta: &mut SystemMeta) {
|
|
self.0.new_archetype(archetype, system_meta);
|
|
}
|
|
|
|
fn apply(&mut self, world: &mut World) {
|
|
self.0.apply(world);
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::SystemParam;
|
|
use crate::{
|
|
self as bevy_ecs, // Necessary for the `SystemParam` Derive when used inside `bevy_ecs`.
|
|
query::{ReadOnlyWorldQuery, WorldQuery},
|
|
system::Query,
|
|
};
|
|
|
|
// Compile test for #2838
|
|
#[derive(SystemParam)]
|
|
pub struct SpecialQuery<
|
|
'w,
|
|
's,
|
|
Q: WorldQuery + Send + Sync + 'static,
|
|
F: ReadOnlyWorldQuery + Send + Sync + 'static = (),
|
|
> {
|
|
_query: Query<'w, 's, Q, F>,
|
|
}
|
|
}
|