use crate::{
archetype::{Archetype, ArchetypeGeneration, ArchetypeId},
change_detection::Tick,
component::ComponentId,
entity::{Entity, EntityEquivalent, EntitySet, UniqueEntityArray},
entity_disabling::DefaultQueryFilters,
prelude::FromWorld,
query::{FilteredAccess, QueryCombinationIter, QueryIter, QueryParIter, WorldQuery},
storage::{SparseSetIndex, TableId},
system::Query,
world::{unsafe_world_cell::UnsafeWorldCell, World, WorldId},
};
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
use crate::entity::UniqueEntityEquivalentSlice;
use alloc::vec::Vec;
use bevy_utils::prelude::DebugName;
use core::{fmt, ptr};
use fixedbitset::FixedBitSet;
use log::warn;
#[cfg(feature = "trace")]
use tracing::Span;
use super::{
NopWorldQuery, QueryBuilder, QueryData, QueryEntityError, QueryFilter, QueryManyIter,
QueryManyUniqueIter, QuerySingleError, ROQueryItem, ReadOnlyQueryData,
};
/// An ID for either a table or an archetype. Used for Query iteration.
///
/// Query iteration is exclusively dense (over tables) or archetypal (over archetypes) based on whether
/// the query filters are dense or not. This is represented by the [`QueryState::is_dense`] field.
///
/// Note that `D::IS_DENSE` and `F::IS_DENSE` have no relationship with `QueryState::is_dense` and
/// any combination of their values can happen.
///
/// This is a union instead of an enum as the usage is determined at compile time, as all [`StorageId`]s for
/// a [`QueryState`] will be all [`TableId`]s or all [`ArchetypeId`]s, and not a mixture of both. This
/// removes the need for discriminator to minimize memory usage and branching during iteration, but requires
/// a safety invariant be verified when disambiguating them.
///
/// # Safety
/// Must be initialized and accessed as a [`TableId`], if both generic parameters to the query are dense.
/// Must be initialized and accessed as an [`ArchetypeId`] otherwise.
#[derive(Clone, Copy)]
pub(super) union StorageId {
pub(super) table_id: TableId,
pub(super) archetype_id: ArchetypeId,
}
/// Provides scoped access to a [`World`] state according to a given [`QueryData`] and [`QueryFilter`].
///
/// This data is cached between system runs, and is used to:
/// - store metadata about which [`Table`] or [`Archetype`] are matched by the query. "Matched" means
/// that the query will iterate over the data in the matched table/archetype.
/// - cache the [`State`] needed to compute the [`Fetch`] struct used to retrieve data
/// from a specific [`Table`] or [`Archetype`]
/// - build iterators that can iterate over the query results
///
/// [`State`]: crate::query::world_query::WorldQuery::State
/// [`Fetch`]: crate::query::world_query::WorldQuery::Fetch
/// [`Table`]: crate::storage::Table
#[repr(C)]
// SAFETY NOTE:
// Do not add any new fields that use the `D` or `F` generic parameters as this may
// make `QueryState::as_transmuted_state` unsound if not done with care.
pub struct QueryState<D: QueryData, F: QueryFilter = ()> {
world_id: WorldId,
pub(crate) archetype_generation: ArchetypeGeneration,
/// Metadata about the [`Table`](crate::storage::Table)s matched by this query.
pub(crate) matched_tables: FixedBitSet,
/// Metadata about the [`Archetype`]s matched by this query.
pub(crate) matched_archetypes: FixedBitSet,
/// [`FilteredAccess`] computed by combining the `D` and `F` access. Used to check which other queries
/// this query can run in parallel with.
/// Note that because we do a zero-cost reference conversion in `Query::as_readonly`,
/// the access for a read-only query may include accesses for the original mutable version,
/// but the `Query` does not have exclusive access to those components.
pub(crate) component_access: FilteredAccess,
// NOTE: we maintain both a bitset and a vec because iterating the vec is faster
pub(super) matched_storage_ids: Vec<StorageId>,
// Represents whether this query iteration is dense or not. When this is true
// `matched_storage_ids` stores `TableId`s, otherwise it stores `ArchetypeId`s.
pub(super) is_dense: bool,
pub(crate) fetch_state: D::State,
pub(crate) filter_state: F::State,
#[cfg(feature = "trace")]
par_iter_span: Span,
}
impl<D: QueryData, F: QueryFilter> fmt::Debug for QueryState<D, F> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("QueryState")
.field("world_id", &self.world_id)
.field("matched_table_count", &self.matched_tables.count_ones(..))
.field(
"matched_archetype_count",
&self.matched_archetypes.count_ones(..),
)
.finish_non_exhaustive()
}
}
impl<D: QueryData, F: QueryFilter> FromWorld for QueryState<D, F> {
fn from_world(world: &mut World) -> Self {
world.query_filtered()
}
}
impl<D: QueryData, F: QueryFilter> QueryState<D, F> {
/// Converts this `QueryState` reference to a `QueryState` that does not access anything mutably.
pub fn as_readonly(&self) -> &QueryState<D::ReadOnly, F> {
// SAFETY: invariant on `WorldQuery` trait upholds that `D::ReadOnly` and `F::ReadOnly`
// have a subset of the access, and match the exact same archetypes/tables as `D`/`F` respectively.
unsafe { self.as_transmuted_state::<D::ReadOnly, F>() }
}
/// Converts this `QueryState` reference to a `QueryState` that does not return any data
/// which can be faster.
///
/// This doesn't use `NopWorldQuery` as it loses filter functionality, for example
/// `NopWorldQuery<Changed<T>>` is functionally equivalent to `With<T>`.
pub(crate) fn as_nop(&self) -> &QueryState<NopWorldQuery<D>, F> {
// SAFETY: `NopWorldQuery` doesn't have any accesses and defers to
// `D` for table/archetype matching
unsafe { self.as_transmuted_state::<NopWorldQuery<D>, F>() }
}
/// Converts this `QueryState` reference to any other `QueryState` with
/// the same `WorldQuery::State` associated types.
///
/// Consider using `as_readonly` or `as_nop` instead which are safe functions.
///
/// # Safety
///
/// `NewD` must have a subset of the access that `D` does and match the exact same archetypes/tables
/// `NewF` must have a subset of the access that `F` does and match the exact same archetypes/tables
pub(crate) unsafe fn as_transmuted_state<
NewD: ReadOnlyQueryData<State = D::State>,
NewF: QueryFilter<State = F::State>,
>(
&self,
) -> &QueryState<NewD, NewF> {
&*ptr::from_ref(self).cast::<QueryState<NewD, NewF>>()
}
/// Returns the components accessed by this query.
pub fn component_access(&self) -> &FilteredAccess {
&self.component_access
}
/// Returns the tables matched by this query.
pub fn matched_tables(&self) -> impl Iterator<Item = TableId> + '_ {
self.matched_tables.ones().map(TableId::from_usize)
}
/// Returns the archetypes matched by this query.
pub fn matched_archetypes(&self) -> impl Iterator<Item = ArchetypeId> + '_ {
self.matched_archetypes.ones().map(ArchetypeId::new)
}
/// Creates a new [`QueryState`] from a given [`World`] and inherits the result of `world.id()`.
pub fn new(world: &mut World) -> Self {
let mut state = Self::new_uninitialized(world);
state.update_archetypes(world);
state
}
/// Creates a new [`QueryState`] from an immutable [`World`] reference and inherits the result of `world.id()`.
///
/// This function may fail if, for example,
/// the components that make up this query have not been registered into the world.
pub fn try_new(world: &World) -> Option<Self> {
let mut state = Self::try_new_uninitialized(world)?;
state.update_archetypes(world);
Some(state)
}
/// Creates a new [`QueryState`] but does not populate it with the matched results from the World yet
///
/// `new_archetype` and its variants must be called on all of the World's archetypes before the
/// state can return valid query results.
fn new_uninitialized(world: &mut World) -> Self {
let fetch_state = D::init_state(world);
let filter_state = F::init_state(world);
Self::from_states_uninitialized(world, fetch_state, filter_state)
}
/// Creates a new [`QueryState`] but does not populate it with the matched results from the World yet
///
/// `new_archetype` and its variants must be called on all of the World's archetypes before the
/// state can return valid query results.
fn try_new_uninitialized(world: &World) -> Option<Self> {
let fetch_state = D::get_state(world.components())?;
let filter_state = F::get_state(world.components())?;
Some(Self::from_states_uninitialized(
world,
fetch_state,
filter_state,
))
}
/// Creates a new [`QueryState`] but does not populate it with the matched results from the World yet
///
/// `new_archetype` and its variants must be called on all of the World's archetypes before the
/// state can return valid query results.
fn from_states_uninitialized(
world: &World,
fetch_state: <D as WorldQuery>::State,
filter_state: <F as WorldQuery>::State,
) -> Self {
let mut component_access = FilteredAccess::default();
D::update_component_access(&fetch_state, &mut component_access);
// Use a temporary empty FilteredAccess for filters. This prevents them from conflicting with the
// main Query's `fetch_state` access. Filters are allowed to conflict with the main query fetch
// because they are evaluated *before* a specific reference is constructed.
let mut filter_component_access = FilteredAccess::default();
F::update_component_access(&filter_state, &mut filter_component_access);
// Merge the temporary filter access with the main access. This ensures that filter access is
// properly considered in a global "cross-query" context (both within systems and across systems).
component_access.extend(&filter_component_access);
// For queries without dynamic filters the dense-ness of the query is equal to the dense-ness
// of its static type parameters.
let mut is_dense = D::IS_DENSE && F::IS_DENSE;
if let Some(default_filters) = world.get_resource::<DefaultQueryFilters>() {
default_filters.modify_access(&mut component_access);
is_dense &= default_filters.is_dense(world.components());
}
Self {
world_id: world.id(),
archetype_generation: ArchetypeGeneration::initial(),
matched_storage_ids: Vec::new(),
is_dense,
fetch_state,
filter_state,
component_access,
matched_tables: Default::default(),
matched_archetypes: Default::default(),
#[cfg(feature = "trace")]
par_iter_span: tracing::info_span!(
"par_for_each",
query = core::any::type_name::<D>(),
filter = core::any::type_name::<F>(),
),
}
}
/// Creates a new [`QueryState`] from a given [`QueryBuilder`] and inherits its [`FilteredAccess`].
pub fn from_builder(builder: &mut QueryBuilder<D, F>) -> Self {
let mut fetch_state = D::init_state(builder.world_mut());
let filter_state = F::init_state(builder.world_mut());
let mut component_access = FilteredAccess::default();
D::update_component_access(&fetch_state, &mut component_access);
D::provide_extra_access(
&mut fetch_state,
component_access.access_mut(),
builder.access().access(),
);
let mut component_access = builder.access().clone();
// For dynamic queries the dense-ness is given by the query builder.
let mut is_dense = builder.is_dense();
if let Some(default_filters) = builder.world().get_resource::<DefaultQueryFilters>() {
default_filters.modify_access(&mut component_access);
is_dense &= default_filters.is_dense(builder.world().components());
}
let mut state = Self {
world_id: builder.world().id(),
archetype_generation: ArchetypeGeneration::initial(),
matched_storage_ids: Vec::new(),
is_dense,
fetch_state,
filter_state,
component_access,
matched_tables: Default::default(),
matched_archetypes: Default::default(),
#[cfg(feature = "trace")]
par_iter_span: tracing::info_span!(
"par_for_each",
data = core::any::type_name::<D>(),
filter = core::any::type_name::<F>(),
),
};
state.update_archetypes(builder.world());
state
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
///
/// This will create read-only queries, see [`Self::query_mut`] for mutable queries.
pub fn query<'w, 's>(&'s mut self, world: &'w World) -> Query<'w, 's, D::ReadOnly, F> {
self.update_archetypes(world);
self.query_manual(world)
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
///
/// This method is slightly more efficient than [`QueryState::query`] in some situations, since
/// it does not update this instance's internal cache. The resulting query may skip an entity that
/// belongs to an archetype that has not been cached.
///
/// To ensure that the cache is up to date, call [`QueryState::update_archetypes`] before this method.
/// The cache is also updated in [`QueryState::new`], [`QueryState::get`], or any method with mutable
/// access to `self`.
///
/// This will create read-only queries, see [`Self::query_mut`] for mutable queries.
pub fn query_manual<'w, 's>(&'s self, world: &'w World) -> Query<'w, 's, D::ReadOnly, F> {
self.validate_world(world.id());
// SAFETY:
// - We have read access to the entire world, and we call `as_readonly()` so the query only performs read access.
// - We called `validate_world`.
unsafe {
self.as_readonly()
.query_unchecked_manual(world.as_unsafe_world_cell_readonly())
}
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
pub fn query_mut<'w, 's>(&'s mut self, world: &'w mut World) -> Query<'w, 's, D, F> {
let last_run = world.last_change_tick();
let this_run = world.change_tick();
// SAFETY: We have exclusive access to the entire world.
unsafe { self.query_unchecked_with_ticks(world.as_unsafe_world_cell(), last_run, this_run) }
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
pub unsafe fn query_unchecked<'w, 's>(
&'s mut self,
world: UnsafeWorldCell<'w>,
) -> Query<'w, 's, D, F> {
self.update_archetypes_unsafe_world_cell(world);
// SAFETY: Caller ensures we have the required access
unsafe { self.query_unchecked_manual(world) }
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
///
/// This method is slightly more efficient than [`QueryState::query_unchecked`] in some situations, since
/// it does not update this instance's internal cache. The resulting query may skip an entity that
/// belongs to an archetype that has not been cached.
///
/// To ensure that the cache is up to date, call [`QueryState::update_archetypes`] before this method.
/// The cache is also updated in [`QueryState::new`], [`QueryState::get`], or any method with mutable
/// access to `self`.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
/// This does not validate that `world.id()` matches `self.world_id`. Calling this on a `world`
/// with a mismatched [`WorldId`] is unsound.
pub unsafe fn query_unchecked_manual<'w, 's>(
&'s self,
world: UnsafeWorldCell<'w>,
) -> Query<'w, 's, D, F> {
let last_run = world.last_change_tick();
let this_run = world.change_tick();
// SAFETY:
// - The caller ensured we have the correct access to the world.
// - The caller ensured that the world matches.
unsafe { self.query_unchecked_manual_with_ticks(world, last_run, this_run) }
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
pub unsafe fn query_unchecked_with_ticks<'w, 's>(
&'s mut self,
world: UnsafeWorldCell<'w>,
last_run: Tick,
this_run: Tick,
) -> Query<'w, 's, D, F> {
self.update_archetypes_unsafe_world_cell(world);
// SAFETY:
// - The caller ensured we have the correct access to the world.
// - We called `update_archetypes_unsafe_world_cell`, which calls `validate_world`.
unsafe { self.query_unchecked_manual_with_ticks(world, last_run, this_run) }
}
/// Creates a [`Query`] from the given [`QueryState`] and [`World`].
///
/// This method is slightly more efficient than [`QueryState::query_unchecked_with_ticks`] in some situations, since
/// it does not update this instance's internal cache. The resulting query may skip an entity that
/// belongs to an archetype that has not been cached.
///
/// To ensure that the cache is up to date, call [`QueryState::update_archetypes`] before this method.
/// The cache is also updated in [`QueryState::new`], [`QueryState::get`], or any method with mutable
/// access to `self`.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
/// This does not validate that `world.id()` matches `self.world_id`. Calling this on a `world`
/// with a mismatched [`WorldId`] is unsound.
pub unsafe fn query_unchecked_manual_with_ticks<'w, 's>(
&'s self,
world: UnsafeWorldCell<'w>,
last_run: Tick,
this_run: Tick,
) -> Query<'w, 's, D, F> {
// SAFETY:
// - The caller ensured we have the correct access to the world.
// - The caller ensured that the world matches.
unsafe { Query::new(world, self, last_run, this_run) }
}
/// Checks if the query is empty for the given [`World`], where the last change and current tick are given.
///
/// This is equivalent to `self.iter().next().is_none()`, and thus the worst case runtime will be `O(n)`
/// where `n` is the number of *potential* matches. This can be notably expensive for queries that rely
/// on non-archetypal filters such as [`Added`], [`Changed`] or [`Spawned`] which must individually check
/// each query result for a match.
///
/// # Panics
///
/// If `world` does not match the one used to call `QueryState::new` for this instance.
///
/// [`Added`]: crate::query::Added
/// [`Changed`]: crate::query::Changed
/// [`Spawned`]: crate::query::Spawned
#[inline]
pub fn is_empty(&self, world: &World, last_run: Tick, this_run: Tick) -> bool {
self.validate_world(world.id());
// SAFETY:
// - We have read access to the entire world, and `is_empty()` only performs read access.
// - We called `validate_world`.
unsafe {
self.query_unchecked_manual_with_ticks(
world.as_unsafe_world_cell_readonly(),
last_run,
this_run,
)
}
.is_empty()
}
/// Returns `true` if the given [`Entity`] matches the query.
///
/// This is always guaranteed to run in `O(1)` time.
#[inline]
pub fn contains(&self, entity: Entity, world: &World, last_run: Tick, this_run: Tick) -> bool {
self.validate_world(world.id());
// SAFETY:
// - We have read access to the entire world, and `is_empty()` only performs read access.
// - We called `validate_world`.
unsafe {
self.query_unchecked_manual_with_ticks(
world.as_unsafe_world_cell_readonly(),
last_run,
this_run,
)
}
.contains(entity)
}
/// Updates the state's internal view of the [`World`]'s archetypes. If this is not called before querying data,
/// the results may not accurately reflect what is in the `world`.
///
/// This is only required if a `manual` method (such as [`Self::get_manual`]) is being called, and it only needs to
/// be called if the `world` has been structurally mutated (i.e. added/removed a component or resource). Users using
/// non-`manual` methods such as [`QueryState::get`] do not need to call this as it will be automatically called for them.
///
/// If you have an [`UnsafeWorldCell`] instead of `&World`, consider using [`QueryState::update_archetypes_unsafe_world_cell`].
///
/// # Panics
///
/// If `world` does not match the one used to call `QueryState::new` for this instance.
#[inline]
pub fn update_archetypes(&mut self, world: &World) {
self.update_archetypes_unsafe_world_cell(world.as_unsafe_world_cell_readonly());
}
/// Updates the state's internal view of the `world`'s archetypes. If this is not called before querying data,
/// the results may not accurately reflect what is in the `world`.
///
/// This is only required if a `manual` method (such as [`Self::get_manual`]) is being called, and it only needs to
/// be called if the `world` has been structurally mutated (i.e. added/removed a component or resource). Users using
/// non-`manual` methods such as [`QueryState::get`] do not need to call this as it will be automatically called for them.
///
/// # Note
///
/// This method only accesses world metadata.
///
/// # Panics
///
/// If `world` does not match the one used to call `QueryState::new` for this instance.
pub fn update_archetypes_unsafe_world_cell(&mut self, world: UnsafeWorldCell) {
self.validate_world(world.id());
if self.component_access.required.is_empty() {
let archetypes = world.archetypes();
let old_generation =
core::mem::replace(&mut self.archetype_generation, archetypes.generation());
for archetype in &archetypes[old_generation..] {
// SAFETY: The validate_world call ensures that the world is the same the QueryState
// was initialized from.
unsafe {
self.new_archetype(archetype);
}
}
} else {
// skip if we are already up to date
if self.archetype_generation == world.archetypes().generation() {
return;
}
// if there are required components, we can optimize by only iterating through archetypes
// that contain at least one of the required components
let potential_archetypes = self
.component_access
.required
.ones()
.filter_map(|idx| {
let component_id = ComponentId::get_sparse_set_index(idx);
world
.archetypes()
.component_index()
.get(&component_id)
.map(|index| index.keys())
})
// select the component with the fewest archetypes
.min_by_key(ExactSizeIterator::len);
if let Some(archetypes) = potential_archetypes {
for archetype_id in archetypes {
// exclude archetypes that have already been processed
if archetype_id < &self.archetype_generation.0 {
continue;
}
// SAFETY: get_potential_archetypes only returns archetype ids that are valid for the world
let archetype = &world.archetypes()[*archetype_id];
// SAFETY: The validate_world call ensures that the world is the same the QueryState
// was initialized from.
unsafe {
self.new_archetype(archetype);
}
}
}
self.archetype_generation = world.archetypes().generation();
}
}
/// # Panics
///
/// If `world_id` does not match the [`World`] used to call `QueryState::new` for this instance.
///
/// Many unsafe query methods require the world to match for soundness. This function is the easiest
/// way of ensuring that it matches.
#[inline]
#[track_caller]
pub fn validate_world(&self, world_id: WorldId) {
#[inline(never)]
#[track_caller]
#[cold]
fn panic_mismatched(this: WorldId, other: WorldId) -> ! {
panic!("Encountered a mismatched World. This QueryState was created from {this:?}, but a method was called using {other:?}.");
}
if self.world_id != world_id {
panic_mismatched(self.world_id, world_id);
}
}
/// Update the current [`QueryState`] with information from the provided [`Archetype`]
/// (if applicable, i.e. if the archetype has any intersecting [`ComponentId`] with the current [`QueryState`]).
///
/// # Safety
/// `archetype` must be from the `World` this state was initialized from.
pub unsafe fn new_archetype(&mut self, archetype: &Archetype) {
if D::matches_component_set(&self.fetch_state, &|id| archetype.contains(id))
&& F::matches_component_set(&self.filter_state, &|id| archetype.contains(id))
&& self.matches_component_set(&|id| archetype.contains(id))
{
let archetype_index = archetype.id().index();
if !self.matched_archetypes.contains(archetype_index) {
self.matched_archetypes.grow_and_insert(archetype_index);
if !self.is_dense {
self.matched_storage_ids.push(StorageId {
archetype_id: archetype.id(),
});
}
}
let table_index = archetype.table_id().as_usize();
if !self.matched_tables.contains(table_index) {
self.matched_tables.grow_and_insert(table_index);
if self.is_dense {
self.matched_storage_ids.push(StorageId {
table_id: archetype.table_id(),
});
}
}
}
}
/// Returns `true` if this query matches a set of components. Otherwise, returns `false`.
pub fn matches_component_set(&self, set_contains_id: &impl Fn(ComponentId) -> bool) -> bool {
self.component_access.filter_sets.iter().any(|set| {
set.with
.ones()
.all(|index| set_contains_id(ComponentId::get_sparse_set_index(index)))
&& set
.without
.ones()
.all(|index| !set_contains_id(ComponentId::get_sparse_set_index(index)))
})
}
/// Use this to transform a [`QueryState`] into a more generic [`QueryState`].
/// This can be useful for passing to another function that might take the more general form.
/// See [`Query::transmute_lens`](crate::system::Query::transmute_lens) for more details.
///
/// You should not call [`update_archetypes`](Self::update_archetypes) on the returned [`QueryState`] as the result will be unpredictable.
/// You might end up with a mix of archetypes that only matched the original query + archetypes that only match
/// the new [`QueryState`]. Most of the safe methods on [`QueryState`] call [`QueryState::update_archetypes`] internally, so this
/// best used through a [`Query`]
pub fn transmute<'a, NewD: QueryData>(
&self,
world: impl Into<UnsafeWorldCell<'a>>,
) -> QueryState<NewD> {
self.transmute_filtered::<NewD, ()>(world.into())
}
/// Creates a new [`QueryState`] with the same underlying [`FilteredAccess`], matched tables and archetypes
/// as self but with a new type signature.
///
/// Panics if `NewD` or `NewF` require accesses that this query does not have.
pub fn transmute_filtered<'a, NewD: QueryData, NewF: QueryFilter>(
&self,
world: impl Into<UnsafeWorldCell<'a>>,
) -> QueryState<NewD, NewF> {
let world = world.into();
self.validate_world(world.id());
let mut component_access = FilteredAccess::default();
let mut fetch_state = NewD::get_state(world.components()).expect("Could not create fetch_state, Please initialize all referenced components before transmuting.");
let filter_state = NewF::get_state(world.components()).expect("Could not create filter_state, Please initialize all referenced components before transmuting.");
let mut self_access = self.component_access.clone();
if D::IS_READ_ONLY {
// The current state was transmuted from a mutable
// `QueryData` to a read-only one.
// Ignore any write access in the current state.
self_access.access_mut().clear_writes();
}
NewD::update_component_access(&fetch_state, &mut component_access);
NewD::provide_extra_access(
&mut fetch_state,
component_access.access_mut(),
self_access.access(),
);
let mut filter_component_access = FilteredAccess::default();
NewF::update_component_access(&filter_state, &mut filter_component_access);
component_access.extend(&filter_component_access);
assert!(
component_access.is_subset(&self_access),
"Transmuted state for {} attempts to access terms that are not allowed by original state {}.",
DebugName::type_name::<(NewD, NewF)>(), DebugName::type_name::<(D, F)>()
);
// For transmuted queries, the dense-ness of the query is equal to the dense-ness of the original query.
//
// We ensure soundness using `FilteredAccess::required`.
//
// Any `WorldQuery` implementations that rely on a query being sparse for soundness,
// including `&`, `&mut`, `Ref`, and `Mut`, will add a sparse set component to the `required` set.
// (`Option<&Sparse>` and `Has<Sparse>` will incorrectly report a component as never being present
// when doing dense iteration, but are not unsound. See https://github.com/bevyengine/bevy/issues/16397)
//
// And any query with a sparse set component in the `required` set must have `is_dense = false`.
// For static queries, the `WorldQuery` implementations ensure this.
// For dynamic queries, anything that adds a `required` component also adds a `with` filter.
//
// The `component_access.is_subset()` check ensures that if the new query has a sparse set component in the `required` set,
// then the original query must also have had that component in the `required` set.
// Therefore, if the `WorldQuery` implementations rely on a query being sparse for soundness,
// then there was a sparse set component in the `required` set, and the query has `is_dense = false`.
let is_dense = self.is_dense;
QueryState {
world_id: self.world_id,
archetype_generation: self.archetype_generation,
matched_storage_ids: self.matched_storage_ids.clone(),
is_dense,
fetch_state,
filter_state,
component_access: self_access,
matched_tables: self.matched_tables.clone(),
matched_archetypes: self.matched_archetypes.clone(),
#[cfg(feature = "trace")]
par_iter_span: tracing::info_span!(
"par_for_each",
query = core::any::type_name::<NewD>(),
filter = core::any::type_name::<NewF>(),
),
}
}
/// Use this to combine two queries. The data accessed will be the intersection
/// of archetypes included in both queries. This can be useful for accessing a
/// subset of the entities between two queries.
///
/// You should not call `update_archetypes` on the returned `QueryState` as the result
/// could be unpredictable. You might end up with a mix of archetypes that only matched
/// the original query + archetypes that only match the new `QueryState`. Most of the
/// safe methods on `QueryState` call [`QueryState::update_archetypes`] internally, so
/// this is best used through a `Query`.
///
/// ## Performance
///
/// This will have similar performance as constructing a new `QueryState` since much of internal state
/// needs to be reconstructed. But it will be a little faster as it only needs to compare the intersection
/// of matching archetypes rather than iterating over all archetypes.
///
/// ## Panics
///
/// Will panic if `NewD` contains accesses not in `Q` or `OtherQ`.
pub fn join<'a, OtherD: QueryData, NewD: QueryData>(
&self,
world: impl Into<UnsafeWorldCell<'a>>,
other: &QueryState<OtherD>,
) -> QueryState<NewD, ()> {
self.join_filtered::<_, (), NewD, ()>(world, other)
}
/// Use this to combine two queries. The data accessed will be the intersection
/// of archetypes included in both queries.
///
/// ## Panics
///
/// Will panic if `NewD` or `NewF` requires accesses not in `Q` or `OtherQ`.
pub fn join_filtered<
'a,
OtherD: QueryData,
OtherF: QueryFilter,
NewD: QueryData,
NewF: QueryFilter,
>(
&self,
world: impl Into<UnsafeWorldCell<'a>>,
other: &QueryState<OtherD, OtherF>,
) -> QueryState<NewD, NewF> {
if self.world_id != other.world_id {
panic!("Joining queries initialized on different worlds is not allowed.");
}
let world = world.into();
self.validate_world(world.id());
let mut component_access = FilteredAccess::default();
let mut new_fetch_state = NewD::get_state(world.components())
.expect("Could not create fetch_state, Please initialize all referenced components before transmuting.");
let new_filter_state = NewF::get_state(world.components())
.expect("Could not create filter_state, Please initialize all referenced components before transmuting.");
let mut joined_component_access = self.component_access.clone();
joined_component_access.extend(&other.component_access);
if D::IS_READ_ONLY && self.component_access.access().has_any_write()
|| OtherD::IS_READ_ONLY && other.component_access.access().has_any_write()
{
// One of the input states was transmuted from a mutable
// `QueryData` to a read-only one.
// Ignore any write access in that current state.
// The simplest way to do this is to clear *all* writes
// and then add back in any writes that are valid
joined_component_access.access_mut().clear_writes();
if !D::IS_READ_ONLY {
joined_component_access
.access_mut()
.extend(self.component_access.access());
}
if !OtherD::IS_READ_ONLY {
joined_component_access
.access_mut()
.extend(other.component_access.access());
}
}
NewD::update_component_access(&new_fetch_state, &mut component_access);
NewD::provide_extra_access(
&mut new_fetch_state,
component_access.access_mut(),
joined_component_access.access(),
);
let mut new_filter_component_access = FilteredAccess::default();
NewF::update_component_access(&new_filter_state, &mut new_filter_component_access);
component_access.extend(&new_filter_component_access);
assert!(
component_access.is_subset(&joined_component_access),
"Joined state for {} attempts to access terms that are not allowed by state {} joined with {}.",
DebugName::type_name::<(NewD, NewF)>(), DebugName::type_name::<(D, F)>(), DebugName::type_name::<(OtherD, OtherF)>()
);
if self.archetype_generation != other.archetype_generation {
warn!("You have tried to join queries with different archetype_generations. This could lead to unpredictable results.");
}
// the join is dense of both the queries were dense.
let is_dense = self.is_dense && other.is_dense;
// take the intersection of the matched ids
let mut matched_tables = self.matched_tables.clone();
let mut matched_archetypes = self.matched_archetypes.clone();
matched_tables.intersect_with(&other.matched_tables);
matched_archetypes.intersect_with(&other.matched_archetypes);
let matched_storage_ids = if is_dense {
matched_tables
.ones()
.map(|id| StorageId {
table_id: TableId::from_usize(id),
})
.collect()
} else {
matched_archetypes
.ones()
.map(|id| StorageId {
archetype_id: ArchetypeId::new(id),
})
.collect()
};
QueryState {
world_id: self.world_id,
archetype_generation: self.archetype_generation,
matched_storage_ids,
is_dense,
fetch_state: new_fetch_state,
filter_state: new_filter_state,
component_access: joined_component_access,
matched_tables,
matched_archetypes,
#[cfg(feature = "trace")]
par_iter_span: tracing::info_span!(
"par_for_each",
query = core::any::type_name::<NewD>(),
filter = core::any::type_name::<NewF>(),
),
}
}
/// Gets the query result for the given [`World`] and [`Entity`].
///
/// This can only be called for read-only queries, see [`Self::get_mut`] for write-queries.
///
/// If you need to get multiple items at once but get borrowing errors,
/// consider using [`Self::update_archetypes`] followed by multiple [`Self::get_manual`] calls,
/// or making a single call with [`Self::get_many`] or [`Self::iter_many`].
///
/// This is always guaranteed to run in `O(1)` time.
#[inline]
pub fn get<'w>(
&mut self,
world: &'w World,
entity: Entity,
) -> Result<ROQueryItem<'w, '_, D>, QueryEntityError> {
self.query(world).get_inner(entity)
}
/// Returns the read-only query results for the given array of [`Entity`].
///
/// In case of a nonexisting entity or mismatched component, a [`QueryEntityError`] is
/// returned instead.
///
/// Note that the unlike [`QueryState::get_many_mut`], the entities passed in do not need to be unique.
///
/// # Examples
///
/// ```
/// use bevy_ecs::prelude::*;
/// use bevy_ecs::query::QueryEntityError;
///
/// #[derive(Component, PartialEq, Debug)]
/// struct A(usize);
///
/// let mut world = World::new();
/// let entity_vec: Vec<Entity> = (0..3).map(|i|world.spawn(A(i)).id()).collect();
/// let entities: [Entity; 3] = entity_vec.try_into().unwrap();
///
/// world.spawn(A(73));
///
/// let mut query_state = world.query::<&A>();
///
/// let component_values = query_state.get_many(&world, entities).unwrap();
///
/// assert_eq!(component_values, [&A(0), &A(1), &A(2)]);
///
/// let wrong_entity = Entity::from_raw_u32(365).unwrap();
///
/// assert_eq!(match query_state.get_many(&mut world, [wrong_entity]).unwrap_err() {QueryEntityError::NotSpawned(error) => error.entity(), _ => panic!()}, wrong_entity);
/// ```
#[inline]
pub fn get_many<'w, const N: usize>(
&mut self,
world: &'w World,
entities: [Entity; N],
) -> Result<[ROQueryItem<'w, '_, D>; N], QueryEntityError> {
self.query(world).get_many_inner(entities)
}
/// Returns the read-only query results for the given [`UniqueEntityArray`].
///
/// In case of a nonexisting entity or mismatched component, a [`QueryEntityError`] is
/// returned instead.
///
/// # Examples
///
/// ```
/// use bevy_ecs::{prelude::*, query::QueryEntityError, entity::{EntitySetIterator, UniqueEntityArray, UniqueEntityVec}};
///
/// #[derive(Component, PartialEq, Debug)]
/// struct A(usize);
///
/// let mut world = World::new();
/// let entity_set: UniqueEntityVec = world.spawn_batch((0..3).map(A)).collect_set();
/// let entity_set: UniqueEntityArray<3> = entity_set.try_into().unwrap();
///
/// world.spawn(A(73));
///
/// let mut query_state = world.query::<&A>();
///
/// let component_values = query_state.get_many_unique(&world, entity_set).unwrap();
///
/// assert_eq!(component_values, [&A(0), &A(1), &A(2)]);
///
/// let wrong_entity = Entity::from_raw_u32(365).unwrap();
///
/// assert_eq!(match query_state.get_many_unique(&mut world, UniqueEntityArray::from([wrong_entity])).unwrap_err() {QueryEntityError::NotSpawned(error) => error.entity(), _ => panic!()}, wrong_entity);
/// ```
#[inline]
pub fn get_many_unique<'w, const N: usize>(
&mut self,
world: &'w World,
entities: UniqueEntityArray<N>,
) -> Result<[ROQueryItem<'w, '_, D>; N], QueryEntityError> {
self.query(world).get_many_unique_inner(entities)
}
/// Gets the query result for the given [`World`] and [`Entity`].
///
/// This is always guaranteed to run in `O(1)` time.
#[inline]
pub fn get_mut<'w>(
&mut self,
world: &'w mut World,
entity: Entity,
) -> Result<D::Item<'w, '_>, QueryEntityError> {
self.query_mut(world).get_inner(entity)
}
/// Returns the query results for the given array of [`Entity`].
///
/// In case of a nonexisting entity or mismatched component, a [`QueryEntityError`] is
/// returned instead.
///
/// ```
/// use bevy_ecs::prelude::*;
/// use bevy_ecs::query::QueryEntityError;
///
/// #[derive(Component, PartialEq, Debug)]
/// struct A(usize);
///
/// let mut world = World::new();
///
/// let entities: Vec<Entity> = (0..3).map(|i|world.spawn(A(i)).id()).collect();
/// let entities: [Entity; 3] = entities.try_into().unwrap();
///
/// world.spawn(A(73));
///
/// let mut query_state = world.query::<&mut A>();
///
/// let mut mutable_component_values = query_state.get_many_mut(&mut world, entities).unwrap();
///
/// for mut a in &mut mutable_component_values {
/// a.0 += 5;
/// }
///
/// let component_values = query_state.get_many(&world, entities).unwrap();
///
/// assert_eq!(component_values, [&A(5), &A(6), &A(7)]);
///
/// let wrong_entity = Entity::from_raw_u32(57).unwrap();
/// let invalid_entity = world.spawn_empty().id();
///
/// assert_eq!(match query_state.get_many(&mut world, [wrong_entity]).unwrap_err() {QueryEntityError::NotSpawned(error) => error.entity(), _ => panic!()}, wrong_entity);
/// assert_eq!(match query_state.get_many_mut(&mut world, [invalid_entity]).unwrap_err() {QueryEntityError::QueryDoesNotMatch(entity, _) => entity, _ => panic!()}, invalid_entity);
/// assert_eq!(query_state.get_many_mut(&mut world, [entities[0], entities[0]]).unwrap_err(), QueryEntityError::AliasedMutability(entities[0]));
/// ```
#[inline]
pub fn get_many_mut<'w, const N: usize>(
&mut self,
world: &'w mut World,
entities: [Entity; N],
) -> Result<[D::Item<'w, '_>; N], QueryEntityError> {
self.query_mut(world).get_many_mut_inner(entities)
}
/// Returns the query results for the given [`UniqueEntityArray`].
///
/// In case of a nonexisting entity or mismatched component, a [`QueryEntityError`] is
/// returned instead.
///
/// ```
/// use bevy_ecs::{prelude::*, query::QueryEntityError, entity::{EntitySetIterator, UniqueEntityArray, UniqueEntityVec}};
///
/// #[derive(Component, PartialEq, Debug)]
/// struct A(usize);
///
/// let mut world = World::new();
///
/// let entity_set: UniqueEntityVec = world.spawn_batch((0..3).map(A)).collect_set();
/// let entity_set: UniqueEntityArray<3> = entity_set.try_into().unwrap();
///
/// world.spawn(A(73));
///
/// let mut query_state = world.query::<&mut A>();
///
/// let mut mutable_component_values = query_state.get_many_unique_mut(&mut world, entity_set).unwrap();
///
/// for mut a in &mut mutable_component_values {
/// a.0 += 5;
/// }
///
/// let component_values = query_state.get_many_unique(&world, entity_set).unwrap();
///
/// assert_eq!(component_values, [&A(5), &A(6), &A(7)]);
///
/// let wrong_entity = Entity::from_raw_u32(57).unwrap();
/// let invalid_entity = world.spawn_empty().id();
///
/// assert_eq!(match query_state.get_many_unique(&mut world, UniqueEntityArray::from([wrong_entity])).unwrap_err() {QueryEntityError::NotSpawned(error) => error.entity(), _ => panic!()}, wrong_entity);
/// assert_eq!(match query_state.get_many_unique_mut(&mut world, UniqueEntityArray::from([invalid_entity])).unwrap_err() {QueryEntityError::QueryDoesNotMatch(entity, _) => entity, _ => panic!()}, invalid_entity);
/// ```
#[inline]
pub fn get_many_unique_mut<'w, const N: usize>(
&mut self,
world: &'w mut World,
entities: UniqueEntityArray<N>,
) -> Result<[D::Item<'w, '_>; N], QueryEntityError> {
self.query_mut(world).get_many_unique_inner(entities)
}
/// Gets the query result for the given [`World`] and [`Entity`].
///
/// This method is slightly more efficient than [`QueryState::get`] in some situations, since
/// it does not update this instance's internal cache. This method will return an error if `entity`
/// belongs to an archetype that has not been cached.
///
/// To ensure that the cache is up to date, call [`QueryState::update_archetypes`] before this method.
/// The cache is also updated in [`QueryState::new`], `QueryState::get`, or any method with mutable
/// access to `self`.
///
/// This can only be called for read-only queries, see [`Self::get_mut`] for mutable queries.
///
/// This is always guaranteed to run in `O(1)` time.
#[inline]
pub fn get_manual<'w>(
&self,
world: &'w World,
entity: Entity,
) -> Result<ROQueryItem<'w, '_, D>, QueryEntityError> {
self.query_manual(world).get_inner(entity)
}
/// Gets the query result for the given [`World`] and [`Entity`].
///
/// This is always guaranteed to run in `O(1)` time.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
#[inline]
pub unsafe fn get_unchecked<'w>(
&mut self,
world: UnsafeWorldCell<'w>,
entity: Entity,
) -> Result<D::Item<'w, '_>, QueryEntityError> {
// SAFETY: Upheld by caller
unsafe { self.query_unchecked(world) }.get_inner(entity)
}
/// Returns an [`Iterator`] over the query results for the given [`World`].
///
/// This can only be called for read-only queries, see [`Self::iter_mut`] for write-queries.
///
/// If you need to iterate multiple times at once but get borrowing errors,
/// consider using [`Self::update_archetypes`] followed by multiple [`Self::iter_manual`] calls.
#[inline]
pub fn iter<'w, 's>(&'s mut self, world: &'w World) -> QueryIter<'w, 's, D::ReadOnly, F> {
self.query(world).into_iter()
}
/// Returns an [`Iterator`] over the query results for the given [`World`].
///
/// This iterator is always guaranteed to return results from each matching entity once and only once.
/// Iteration order is not guaranteed.
#[inline]
pub fn iter_mut<'w, 's>(&'s mut self, world: &'w mut World) -> QueryIter<'w, 's, D, F> {
self.query_mut(world).into_iter()
}
/// Returns an [`Iterator`] over the query results for the given [`World`] without updating the query's archetypes.
/// Archetypes must be manually updated before by using [`Self::update_archetypes`].
///
/// This iterator is always guaranteed to return results from each matching entity once and only once.
/// Iteration order is not guaranteed.
///
/// This can only be called for read-only queries.
#[inline]
pub fn iter_manual<'w, 's>(&'s self, world: &'w World) -> QueryIter<'w, 's, D::ReadOnly, F> {
self.query_manual(world).into_iter()
}
/// Returns an [`Iterator`] over all possible combinations of `K` query results without repetition.
/// This can only be called for read-only queries.
///
/// A combination is an arrangement of a collection of items where order does not matter.
///
/// `K` is the number of items that make up each subset, and the number of items returned by the iterator.
/// `N` is the number of total entities output by query.
///
/// For example, given the list [1, 2, 3, 4], where `K` is 2, the combinations without repeats are
/// [1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4].
/// And in this case, `N` would be defined as 4 since the size of the input list is 4.
///
/// For combinations of size `K` of query taking `N` inputs, you will get:
/// - if `K == N`: one combination of all query results
/// - if `K < N`: all possible `K`-sized combinations of query results, without repetition
/// - if `K > N`: empty set (no `K`-sized combinations exist)
///
/// The `iter_combinations` method does not guarantee order of iteration.
///
/// This iterator is always guaranteed to return results from each unique pair of matching entities.
/// Iteration order is not guaranteed.
///
/// This can only be called for read-only queries, see [`Self::iter_combinations_mut`] for
/// write-queries.
#[inline]
pub fn iter_combinations<'w, 's, const K: usize>(
&'s mut self,
world: &'w World,
) -> QueryCombinationIter<'w, 's, D::ReadOnly, F, K> {
self.query(world).iter_combinations_inner()
}
/// Returns an [`Iterator`] over all possible combinations of `K` query results without repetition.
///
/// A combination is an arrangement of a collection of items where order does not matter.
///
/// `K` is the number of items that make up each subset, and the number of items returned by the iterator.
/// `N` is the number of total entities output by query.
///
/// For example, given the list [1, 2, 3, 4], where `K` is 2, the combinations without repeats are
/// [1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4].
/// And in this case, `N` would be defined as 4 since the size of the input list is 4.
///
/// For combinations of size `K` of query taking `N` inputs, you will get:
/// - if `K == N`: one combination of all query results
/// - if `K < N`: all possible `K`-sized combinations of query results, without repetition
/// - if `K > N`: empty set (no `K`-sized combinations exist)
///
/// The `iter_combinations_mut` method does not guarantee order of iteration.
#[inline]
pub fn iter_combinations_mut<'w, 's, const K: usize>(
&'s mut self,
world: &'w mut World,
) -> QueryCombinationIter<'w, 's, D, F, K> {
self.query_mut(world).iter_combinations_inner()
}
/// Returns an [`Iterator`] over the read-only query items generated from an [`Entity`] list.
///
/// Items are returned in the order of the list of entities.
/// Entities that don't match the query are skipped.
///
/// If you need to iterate multiple times at once but get borrowing errors,
/// consider using [`Self::update_archetypes`] followed by multiple [`Self::iter_many_manual`] calls.
///
/// # See also
///
/// - [`iter_many_mut`](Self::iter_many_mut) to get mutable query items.
#[inline]
pub fn iter_many<'w, 's, EntityList: IntoIterator<Item: EntityEquivalent>>(
&'s mut self,
world: &'w World,
entities: EntityList,
) -> QueryManyIter<'w, 's, D::ReadOnly, F, EntityList::IntoIter> {
self.query(world).iter_many_inner(entities)
}
/// Returns an [`Iterator`] over the read-only query items generated from an [`Entity`] list.
///
/// Items are returned in the order of the list of entities.
/// Entities that don't match the query are skipped.
///
/// If `world` archetypes changed since [`Self::update_archetypes`] was last called,
/// this will skip entities contained in new archetypes.
///
/// This can only be called for read-only queries.
///
/// # See also
///
/// - [`iter_many`](Self::iter_many) to update archetypes.
/// - [`iter_manual`](Self::iter_manual) to iterate over all query items.
#[inline]
pub fn iter_many_manual<'w, 's, EntityList: IntoIterator<Item: EntityEquivalent>>(
&'s self,
world: &'w World,
entities: EntityList,
) -> QueryManyIter<'w, 's, D::ReadOnly, F, EntityList::IntoIter> {
self.query_manual(world).iter_many_inner(entities)
}
/// Returns an iterator over the query items generated from an [`Entity`] list.
///
/// Items are returned in the order of the list of entities.
/// Entities that don't match the query are skipped.
#[inline]
pub fn iter_many_mut<'w, 's, EntityList: IntoIterator<Item: EntityEquivalent>>(
&'s mut self,
world: &'w mut World,
entities: EntityList,
) -> QueryManyIter<'w, 's, D, F, EntityList::IntoIter> {
self.query_mut(world).iter_many_inner(entities)
}
/// Returns an [`Iterator`] over the unique read-only query items generated from an [`EntitySet`].
///
/// Items are returned in the order of the list of entities.
/// Entities that don't match the query are skipped.
///
/// # See also
///
/// - [`iter_many_unique_mut`](Self::iter_many_unique_mut) to get mutable query items.
#[inline]
pub fn iter_many_unique<'w, 's, EntityList: EntitySet>(
&'s mut self,
world: &'w World,
entities: EntityList,
) -> QueryManyUniqueIter<'w, 's, D::ReadOnly, F, EntityList::IntoIter> {
self.query(world).iter_many_unique_inner(entities)
}
/// Returns an [`Iterator`] over the unique read-only query items generated from an [`EntitySet`].
///
/// Items are returned in the order of the list of entities.
/// Entities that don't match the query are skipped.
///
/// If `world` archetypes changed since [`Self::update_archetypes`] was last called,
/// this will skip entities contained in new archetypes.
///
/// This can only be called for read-only queries.
///
/// # See also
///
/// - [`iter_many_unique`](Self::iter_many) to update archetypes.
/// - [`iter_many`](Self::iter_many) to iterate over a non-unique entity list.
/// - [`iter_manual`](Self::iter_manual) to iterate over all query items.
#[inline]
pub fn iter_many_unique_manual<'w, 's, EntityList: EntitySet>(
&'s self,
world: &'w World,
entities: EntityList,
) -> QueryManyUniqueIter<'w, 's, D::ReadOnly, F, EntityList::IntoIter> {
self.query_manual(world).iter_many_unique_inner(entities)
}
/// Returns an iterator over the unique query items generated from an [`EntitySet`].
///
/// Items are returned in the order of the list of entities.
/// Entities that don't match the query are skipped.
#[inline]
pub fn iter_many_unique_mut<'w, 's, EntityList: EntitySet>(
&'s mut self,
world: &'w mut World,
entities: EntityList,
) -> QueryManyUniqueIter<'w, 's, D, F, EntityList::IntoIter> {
self.query_mut(world).iter_many_unique_inner(entities)
}
/// Returns an [`Iterator`] over the query results for the given [`World`].
///
/// This iterator is always guaranteed to return results from each matching entity once and only once.
/// Iteration order is not guaranteed.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
#[inline]
pub unsafe fn iter_unchecked<'w, 's>(
&'s mut self,
world: UnsafeWorldCell<'w>,
) -> QueryIter<'w, 's, D, F> {
// SAFETY: Upheld by caller
unsafe { self.query_unchecked(world) }.into_iter()
}
/// Returns an [`Iterator`] over all possible combinations of `K` query results for the
/// given [`World`] without repetition.
/// This can only be called for read-only queries.
///
/// This iterator is always guaranteed to return results from each unique pair of matching entities.
/// Iteration order is not guaranteed.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
#[inline]
pub unsafe fn iter_combinations_unchecked<'w, 's, const K: usize>(
&'s mut self,
world: UnsafeWorldCell<'w>,
) -> QueryCombinationIter<'w, 's, D, F, K> {
// SAFETY: Upheld by caller
unsafe { self.query_unchecked(world) }.iter_combinations_inner()
}
/// Returns a parallel iterator over the query results for the given [`World`].
///
/// This can only be called for read-only queries, see [`par_iter_mut`] for write-queries.
///
/// Note that you must use the `for_each` method to iterate over the
/// results, see [`par_iter_mut`] for an example.
///
/// [`par_iter_mut`]: Self::par_iter_mut
#[inline]
pub fn par_iter<'w, 's>(
&'s mut self,
world: &'w World,
) -> QueryParIter<'w, 's, D::ReadOnly, F> {
self.query(world).par_iter_inner()
}
/// Returns a parallel iterator over the query results for the given [`World`].
///
/// This can only be called for mutable queries, see [`par_iter`] for read-only-queries.
///
/// # Examples
///
/// ```
/// use bevy_ecs::prelude::*;
/// use bevy_ecs::query::QueryEntityError;
///
/// #[derive(Component, PartialEq, Debug)]
/// struct A(usize);
///
/// # bevy_tasks::ComputeTaskPool::get_or_init(|| bevy_tasks::TaskPool::new());
///
/// let mut world = World::new();
///
/// # let entities: Vec<Entity> = (0..3).map(|i| world.spawn(A(i)).id()).collect();
/// # let entities: [Entity; 3] = entities.try_into().unwrap();
///
/// let mut query_state = world.query::<&mut A>();
///
/// query_state.par_iter_mut(&mut world).for_each(|mut a| {
/// a.0 += 5;
/// });
///
/// # let component_values = query_state.get_many(&world, entities).unwrap();
///
/// # assert_eq!(component_values, [&A(5), &A(6), &A(7)]);
///
/// # let wrong_entity = Entity::from_raw_u32(57).unwrap();
/// # let invalid_entity = world.spawn_empty().id();
///
/// # assert_eq!(match query_state.get_many(&mut world, [wrong_entity]).unwrap_err() {QueryEntityError::NotSpawned(error) => error.entity(), _ => panic!()}, wrong_entity);
/// assert_eq!(match query_state.get_many_mut(&mut world, [invalid_entity]).unwrap_err() {QueryEntityError::QueryDoesNotMatch(entity, _) => entity, _ => panic!()}, invalid_entity);
/// # assert_eq!(query_state.get_many_mut(&mut world, [entities[0], entities[0]]).unwrap_err(), QueryEntityError::AliasedMutability(entities[0]));
/// ```
///
/// # Panics
/// The [`ComputeTaskPool`] is not initialized. If using this from a query that is being
/// initialized and run from the ECS scheduler, this should never panic.
///
/// [`par_iter`]: Self::par_iter
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn par_iter_mut<'w, 's>(&'s mut self, world: &'w mut World) -> QueryParIter<'w, 's, D, F> {
self.query_mut(world).par_iter_inner()
}
/// Runs `func` on each query result in parallel for the given [`World`], where the last change and
/// the current change tick are given. This is faster than the equivalent
/// `iter()` method, but cannot be chained like a normal [`Iterator`].
///
/// # Panics
/// The [`ComputeTaskPool`] is not initialized. If using this from a query that is being
/// initialized and run from the ECS scheduler, this should never panic.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
/// This does not validate that `world.id()` matches `self.world_id`. Calling this on a `world`
/// with a mismatched [`WorldId`] is unsound.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
pub(crate) unsafe fn par_fold_init_unchecked_manual<'w, 's, T, FN, INIT>(
&'s self,
init_accum: INIT,
world: UnsafeWorldCell<'w>,
batch_size: u32,
func: FN,
last_run: Tick,
this_run: Tick,
) where
FN: Fn(T, D::Item<'w, 's>) -> T + Send + Sync + Clone,
INIT: Fn() -> T + Sync + Send + Clone,
{
// NOTE: If you are changing query iteration code, remember to update the following places, where relevant:
// QueryIter, QueryIterationCursor, QueryManyIter, QueryCombinationIter,QueryState::par_fold_init_unchecked_manual,
// QueryState::par_many_fold_init_unchecked_manual, QueryState::par_many_unique_fold_init_unchecked_manual
use arrayvec::ArrayVec;
bevy_tasks::ComputeTaskPool::get().scope(|scope| {
// SAFETY: We only access table data that has been registered in `self.component_access`.
let tables = unsafe { &world.storages().tables };
let archetypes = world.archetypes();
let mut batch_queue = ArrayVec::new();
let mut queue_entity_count = 0;
// submit a list of storages which smaller than batch_size as single task
let submit_batch_queue = |queue: &mut ArrayVec<StorageId, 128>| {
if queue.is_empty() {
return;
}
let queue = core::mem::take(queue);
let mut func = func.clone();
let init_accum = init_accum.clone();
scope.spawn(async move {
#[cfg(feature = "trace")]
let _span = self.par_iter_span.enter();
let mut iter = self
.query_unchecked_manual_with_ticks(world, last_run, this_run)
.into_iter();
let mut accum = init_accum();
for storage_id in queue {
accum = iter.fold_over_storage_range(accum, &mut func, storage_id, None);
}
});
};
// submit single storage larger than batch_size
let submit_single = |count, storage_id: StorageId| {
for offset in (0..count).step_by(batch_size as usize) {
let mut func = func.clone();
let init_accum = init_accum.clone();
let len = batch_size.min(count - offset);
let batch = offset..offset + len;
scope.spawn(async move {
#[cfg(feature = "trace")]
let _span = self.par_iter_span.enter();
let accum = init_accum();
self.query_unchecked_manual_with_ticks(world, last_run, this_run)
.into_iter()
.fold_over_storage_range(accum, &mut func, storage_id, Some(batch));
});
}
};
let storage_entity_count = |storage_id: StorageId| -> u32 {
if self.is_dense {
tables[storage_id.table_id].entity_count()
} else {
archetypes[storage_id.archetype_id].len()
}
};
for storage_id in &self.matched_storage_ids {
let count = storage_entity_count(*storage_id);
// skip empty storage
if count == 0 {
continue;
}
// immediately submit large storage
if count >= batch_size {
submit_single(count, *storage_id);
continue;
}
// merge small storage
batch_queue.push(*storage_id);
queue_entity_count += count;
// submit batch_queue
if queue_entity_count >= batch_size || batch_queue.is_full() {
submit_batch_queue(&mut batch_queue);
queue_entity_count = 0;
}
}
submit_batch_queue(&mut batch_queue);
});
}
/// Runs `func` on each query result in parallel for the given [`EntitySet`],
/// where the last change and the current change tick are given. This is faster than the
/// equivalent `iter_many_unique()` method, but cannot be chained like a normal [`Iterator`].
///
/// # Panics
/// The [`ComputeTaskPool`] is not initialized. If using this from a query that is being
/// initialized and run from the ECS scheduler, this should never panic.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
/// This does not validate that `world.id()` matches `self.world_id`. Calling this on a `world`
/// with a mismatched [`WorldId`] is unsound.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
pub(crate) unsafe fn par_many_unique_fold_init_unchecked_manual<'w, 's, T, FN, INIT, E>(
&'s self,
init_accum: INIT,
world: UnsafeWorldCell<'w>,
entity_list: &UniqueEntityEquivalentSlice<E>,
batch_size: u32,
mut func: FN,
last_run: Tick,
this_run: Tick,
) where
FN: Fn(T, D::Item<'w, 's>) -> T + Send + Sync + Clone,
INIT: Fn() -> T + Sync + Send + Clone,
E: EntityEquivalent + Sync,
{
// NOTE: If you are changing query iteration code, remember to update the following places, where relevant:
// QueryIter, QueryIterationCursor, QueryManyIter, QueryCombinationIter,QueryState::par_fold_init_unchecked_manual
// QueryState::par_many_fold_init_unchecked_manual, QueryState::par_many_unique_fold_init_unchecked_manual
bevy_tasks::ComputeTaskPool::get().scope(|scope| {
let chunks = entity_list.chunks_exact(batch_size as usize);
let remainder = chunks.remainder();
for batch in chunks {
let mut func = func.clone();
let init_accum = init_accum.clone();
scope.spawn(async move {
#[cfg(feature = "trace")]
let _span = self.par_iter_span.enter();
let accum = init_accum();
self.query_unchecked_manual_with_ticks(world, last_run, this_run)
.iter_many_unique_inner(batch)
.fold(accum, &mut func);
});
}
#[cfg(feature = "trace")]
let _span = self.par_iter_span.enter();
let accum = init_accum();
self.query_unchecked_manual_with_ticks(world, last_run, this_run)
.iter_many_unique_inner(remainder)
.fold(accum, &mut func);
});
}
}
impl<D: ReadOnlyQueryData, F: QueryFilter> QueryState<D, F> {
/// Runs `func` on each read-only query result in parallel for the given [`Entity`] list,
/// where the last change and the current change tick are given. This is faster than the equivalent
/// `iter_many()` method, but cannot be chained like a normal [`Iterator`].
///
/// # Panics
/// The [`ComputeTaskPool`] is not initialized. If using this from a query that is being
/// initialized and run from the ECS scheduler, this should never panic.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
/// This does not validate that `world.id()` matches `self.world_id`. Calling this on a `world`
/// with a mismatched [`WorldId`] is unsound.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
pub(crate) unsafe fn par_many_fold_init_unchecked_manual<'w, 's, T, FN, INIT, E>(
&'s self,
init_accum: INIT,
world: UnsafeWorldCell<'w>,
entity_list: &[E],
batch_size: u32,
mut func: FN,
last_run: Tick,
this_run: Tick,
) where
FN: Fn(T, D::Item<'w, 's>) -> T + Send + Sync + Clone,
INIT: Fn() -> T + Sync + Send + Clone,
E: EntityEquivalent + Sync,
{
// NOTE: If you are changing query iteration code, remember to update the following places, where relevant:
// QueryIter, QueryIterationCursor, QueryManyIter, QueryCombinationIter, QueryState::par_fold_init_unchecked_manual
// QueryState::par_many_fold_init_unchecked_manual, QueryState::par_many_unique_fold_init_unchecked_manual
bevy_tasks::ComputeTaskPool::get().scope(|scope| {
let chunks = entity_list.chunks_exact(batch_size as usize);
let remainder = chunks.remainder();
for batch in chunks {
let mut func = func.clone();
let init_accum = init_accum.clone();
scope.spawn(async move {
#[cfg(feature = "trace")]
let _span = self.par_iter_span.enter();
let accum = init_accum();
self.query_unchecked_manual_with_ticks(world, last_run, this_run)
.iter_many_inner(batch)
.fold(accum, &mut func);
});
}
#[cfg(feature = "trace")]
let _span = self.par_iter_span.enter();
let accum = init_accum();
self.query_unchecked_manual_with_ticks(world, last_run, this_run)
.iter_many_inner(remainder)
.fold(accum, &mut func);
});
}
}
impl<D: QueryData, F: QueryFilter> QueryState<D, F> {
/// Returns a single immutable query result when there is exactly one entity matching
/// the query.
///
/// This can only be called for read-only queries,
/// see [`single_mut`](Self::single_mut) for write-queries.
///
/// If the number of query results is not exactly one, a [`QuerySingleError`] is returned
/// instead.
///
/// # Example
///
/// Sometimes, you might want to handle the error in a specific way,
/// generally by spawning the missing entity.
///
/// ```rust
/// use bevy_ecs::prelude::*;
/// use bevy_ecs::query::QuerySingleError;
///
/// #[derive(Component)]
/// struct A(usize);
///
/// fn my_system(query: Query<&A>, mut commands: Commands) {
/// match query.single() {
/// Ok(a) => (), // Do something with `a`
/// Err(err) => match err {
/// QuerySingleError::NoEntities(_) => {
/// commands.spawn(A(0));
/// }
/// QuerySingleError::MultipleEntities(_) => panic!("Multiple entities found!"),
/// },
/// }
/// }
/// ```
///
/// However in most cases, this error can simply be handled with a graceful early return.
/// If this is an expected failure mode, you can do this using the `let else` pattern like so:
/// ```rust
/// use bevy_ecs::prelude::*;
///
/// #[derive(Component)]
/// struct A(usize);
///
/// fn my_system(query: Query<&A>) {
/// let Ok(a) = query.single() else {
/// return;
/// };
///
/// // Do something with `a`
/// }
/// ```
///
/// If this is unexpected though, you should probably use the `?` operator
/// in combination with Bevy's error handling apparatus.
///
/// ```rust
/// use bevy_ecs::prelude::*;
///
/// #[derive(Component)]
/// struct A(usize);
///
/// fn my_system(query: Query<&A>) -> Result {
/// let a = query.single()?;
///
/// // Do something with `a`
/// Ok(())
/// }
/// ```
///
/// This allows you to globally control how errors are handled in your application,
/// by setting up a custom error handler.
/// See the [`bevy_ecs::error`] module docs for more information!
/// Commonly, you might want to panic on an error during development, but log the error and continue
/// execution in production.
///
/// Simply unwrapping the [`Result`] also works, but should generally be reserved for tests.
#[inline]
pub fn single<'w>(
&mut self,
world: &'w World,
) -> Result<ROQueryItem<'w, '_, D>, QuerySingleError> {
self.query(world).single_inner()
}
/// Returns a single mutable query result when there is exactly one entity matching
/// the query.
///
/// If the number of query results is not exactly one, a [`QuerySingleError`] is returned
/// instead.
///
/// # Examples
///
/// Please see [`Query::single`] for advice on handling the error.
#[inline]
pub fn single_mut<'w>(
&mut self,
world: &'w mut World,
) -> Result<D::Item<'w, '_>, QuerySingleError> {
self.query_mut(world).single_inner()
}
/// Returns a query result when there is exactly one entity matching the query.
///
/// If the number of query results is not exactly one, a [`QuerySingleError`] is returned
/// instead.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
#[inline]
pub unsafe fn single_unchecked<'w>(
&mut self,
world: UnsafeWorldCell<'w>,
) -> Result<D::Item<'w, '_>, QuerySingleError> {
// SAFETY: Upheld by caller
unsafe { self.query_unchecked(world) }.single_inner()
}
/// Returns a query result when there is exactly one entity matching the query,
/// where the last change and the current change tick are given.
///
/// If the number of query results is not exactly one, a [`QuerySingleError`] is returned
/// instead.
///
/// # Safety
///
/// This does not check for mutable query correctness. To be safe, make sure mutable queries
/// have unique access to the components they query.
/// This does not validate that `world.id()` matches `self.world_id`. Calling this on a `world`
/// with a mismatched [`WorldId`] is unsound.
#[inline]
pub unsafe fn single_unchecked_manual<'w>(
&self,
world: UnsafeWorldCell<'w>,
last_run: Tick,
this_run: Tick,
) -> Result<D::Item<'w, '_>, QuerySingleError> {
// SAFETY:
// - The caller ensured we have the correct access to the world.
// - The caller ensured that the world matches.
unsafe { self.query_unchecked_manual_with_ticks(world, last_run, this_run) }.single_inner()
}
}
impl<D: QueryData, F: QueryFilter> From<QueryBuilder<'_, D, F>> for QueryState<D, F> {
fn from(mut value: QueryBuilder<D, F>) -> Self {
QueryState::from_builder(&mut value)
}
}
#[cfg(test)]
mod tests {
use crate::{
component::Component,
entity_disabling::DefaultQueryFilters,
prelude::*,
system::{QueryLens, RunSystemOnce},
world::{EntityRef, FilteredEntityMut, FilteredEntityRef},
};
#[test]
#[should_panic]
fn right_world_get() {
let mut world_1 = World::new();
let world_2 = World::new();
let mut query_state = world_1.query::<Entity>();
let _panics = query_state.get(&world_2, Entity::from_raw_u32(0).unwrap());
}
#[test]
#[should_panic]
fn right_world_get_many() {
let mut world_1 = World::new();
let world_2 = World::new();
let mut query_state = world_1.query::<Entity>();
let _panics = query_state.get_many(&world_2, []);
}
#[test]
#[should_panic]
fn right_world_get_many_mut() {
let mut world_1 = World::new();
let mut world_2 = World::new();
let mut query_state = world_1.query::<Entity>();
let _panics = query_state.get_many_mut(&mut world_2, []);
}
#[derive(Component, PartialEq, Debug)]
struct A(usize);
#[derive(Component, PartialEq, Debug)]
struct B(usize);
#[derive(Component, PartialEq, Debug)]
struct C(usize);
#[derive(Component)]
struct D;
#[test]
fn can_transmute_to_more_general() {
let mut world = World::new();
world.spawn((A(1), B(0)));
let query_state = world.query::<(&A, &B)>();
let mut new_query_state = query_state.transmute::<&A>(&world);
assert_eq!(new_query_state.iter(&world).len(), 1);
let a = new_query_state.single(&world).unwrap();
assert_eq!(a.0, 1);
}
#[test]
fn cannot_get_data_not_in_original_query() {
let mut world = World::new();
world.spawn((A(0), B(0)));
world.spawn((A(1), B(0), C(0)));
let query_state = world.query_filtered::<(&A, &B), Without<C>>();
let mut new_query_state = query_state.transmute::<&A>(&world);
// even though we change the query to not have Without<C>, we do not get the component with C.
let a = new_query_state.single(&world).unwrap();
assert_eq!(a.0, 0);
}
#[test]
fn can_transmute_empty_tuple() {
let mut world = World::new();
world.register_component::<A>();
let entity = world.spawn(A(10)).id();
let q = world.query_filtered::<(), With<A>>();
let mut q = q.transmute::<Entity>(&world);
assert_eq!(q.single(&world).unwrap(), entity);
}
#[test]
fn can_transmute_immut_fetch() {
let mut world = World::new();
world.spawn(A(10));
let q = world.query::<&A>();
let mut new_q = q.transmute::<Ref<A>>(&world);
assert!(new_q.single(&world).unwrap().is_added());
let q = world.query::<Ref<A>>();
let _ = q.transmute::<&A>(&world);
}
#[test]
fn can_transmute_mut_fetch() {
let mut world = World::new();
world.spawn(A(0));
let q = world.query::<&mut A>();
let _ = q.transmute::<Ref<A>>(&world);
let _ = q.transmute::<&A>(&world);
}
#[test]
fn can_transmute_entity_mut() {
let mut world = World::new();
world.spawn(A(0));
let q: QueryState<EntityMut<'_>> = world.query::<EntityMut>();
let _ = q.transmute::<EntityRef>(&world);
}
#[test]
fn can_generalize_with_option() {
let mut world = World::new();
world.spawn((A(0), B(0)));
let query_state = world.query::<(Option<&A>, &B)>();
let _ = query_state.transmute::<Option<&A>>(&world);
let _ = query_state.transmute::<&B>(&world);
}
#[test]
#[should_panic]
fn cannot_transmute_to_include_data_not_in_original_query() {
let mut world = World::new();
world.register_component::<A>();
world.register_component::<B>();
world.spawn(A(0));
let query_state = world.query::<&A>();
let mut _new_query_state = query_state.transmute::<(&A, &B)>(&world);
}
#[test]
#[should_panic]
fn cannot_transmute_immut_to_mut() {
let mut world = World::new();
world.spawn(A(0));
let query_state = world.query::<&A>();
let mut _new_query_state = query_state.transmute::<&mut A>(&world);
}
#[test]
#[should_panic]
fn cannot_transmute_option_to_immut() {
let mut world = World::new();
world.spawn(C(0));
let query_state = world.query::<Option<&A>>();
let mut new_query_state = query_state.transmute::<&A>(&world);
let x = new_query_state.single(&world).unwrap();
assert_eq!(x.0, 1234);
}
#[test]
#[should_panic]
fn cannot_transmute_entity_ref() {
let mut world = World::new();
world.register_component::<A>();
let q = world.query::<EntityRef>();
let _ = q.transmute::<&A>(&world);
}
#[test]
fn can_transmute_filtered_entity() {
let mut world = World::new();
let entity = world.spawn((A(0), B(1))).id();
let query = QueryState::<(Entity, &A, &B)>::new(&mut world)
.transmute::<(Entity, FilteredEntityRef)>(&world);
let mut query = query;
// Our result is completely untyped
let (_entity, entity_ref) = query.single(&world).unwrap();
assert_eq!(entity, entity_ref.id());
assert_eq!(0, entity_ref.get::<A>().unwrap().0);
assert_eq!(1, entity_ref.get::<B>().unwrap().0);
}
#[test]
fn can_transmute_added() {
let mut world = World::new();
let entity_a = world.spawn(A(0)).id();
let mut query = QueryState::<(Entity, &A, Has<B>)>::new(&mut world)
.transmute_filtered::<(Entity, Has<B>), Added<A>>(&world);
assert_eq!((entity_a, false), query.single(&world).unwrap());
world.clear_trackers();
let entity_b = world.spawn((A(0), B(0))).id();
assert_eq!((entity_b, true), query.single(&world).unwrap());
world.clear_trackers();
assert!(query.single(&world).is_err());
}
#[test]
fn can_transmute_changed() {
let mut world = World::new();
let entity_a = world.spawn(A(0)).id();
let mut detection_query = QueryState::<(Entity, &A)>::new(&mut world)
.transmute_filtered::<Entity, Changed<A>>(&world);
let mut change_query = QueryState::<&mut A>::new(&mut world);
assert_eq!(entity_a, detection_query.single(&world).unwrap());
world.clear_trackers();
assert!(detection_query.single(&world).is_err());
change_query.single_mut(&mut world).unwrap().0 = 1;
assert_eq!(entity_a, detection_query.single(&world).unwrap());
}
#[test]
#[should_panic]
fn cannot_transmute_changed_without_access() {
let mut world = World::new();
world.register_component::<A>();
world.register_component::<B>();
let query = QueryState::<&A>::new(&mut world);
let _new_query = query.transmute_filtered::<Entity, Changed<B>>(&world);
}
#[test]
#[should_panic]
fn cannot_transmute_mutable_after_readonly() {
let mut world = World::new();
// Calling this method would mean we had aliasing queries.
fn bad(_: Query<&mut A>, _: Query<&A>) {}
world
.run_system_once(|query: Query<&mut A>| {
let mut readonly = query.as_readonly();
let mut lens: QueryLens<&mut A> = readonly.transmute_lens();
bad(lens.query(), query.as_readonly());
})
.unwrap();
}
// Regression test for #14629
#[test]
#[should_panic]
fn transmute_with_different_world() {
let mut world = World::new();
world.spawn((A(1), B(2)));
let mut world2 = World::new();
world2.register_component::<B>();
world.query::<(&A, &B)>().transmute::<&B>(&world2);
}
/// Regression test for issue #14528
#[test]
fn transmute_from_sparse_to_dense() {
#[derive(Component)]
struct Dense;
#[derive(Component)]
#[component(storage = "SparseSet")]
struct Sparse;
let mut world = World::new();
world.spawn(Dense);
world.spawn((Dense, Sparse));
let mut query = world
.query_filtered::<&Dense, With<Sparse>>()
.transmute::<&Dense>(&world);
let matched = query.iter(&world).count();
assert_eq!(matched, 1);
}
#[test]
fn transmute_from_dense_to_sparse() {
#[derive(Component)]
struct Dense;
#[derive(Component)]
#[component(storage = "SparseSet")]
struct Sparse;
let mut world = World::new();
world.spawn(Dense);
world.spawn((Dense, Sparse));
let mut query = world
.query::<&Dense>()
.transmute_filtered::<&Dense, With<Sparse>>(&world);
// Note: `transmute_filtered` is supposed to keep the same matched tables/archetypes,
// so it doesn't actually filter out those entities without `Sparse` and the iteration
// remains dense.
let matched = query.iter(&world).count();
assert_eq!(matched, 2);
}
#[test]
fn transmute_to_or_filter() {
let mut world = World::new();
world.spawn(());
world.spawn(A(0));
let mut query = world
.query::<Option<&A>>()
.transmute_filtered::<Entity, Or<(With<A>,)>>(&world);
let iter = query.iter(&world);
let len = iter.len();
let count = iter.count();
// `transmute_filtered` keeps the same matched tables, so it should match both entities
// More importantly, `count()` and `len()` should return the same result!
assert_eq!(len, 2);
assert_eq!(count, len);
let mut query = world
.query::<Option<&A>>()
.transmute_filtered::<Entity, Or<(Changed<A>,)>>(&world);
let iter = query.iter(&world);
let count = iter.count();
// The behavior of a non-archetypal filter like `Changed` should be the same as an archetypal one like `With`.
assert_eq!(count, 2);
}
#[test]
fn dense_query_over_option_is_buggy() {
#[derive(Component)]
#[component(storage = "SparseSet")]
struct Sparse;
let mut world = World::new();
world.spawn(Sparse);
let mut query =
QueryState::<EntityRef>::new(&mut world).transmute::<Option<&Sparse>>(&world);
// EntityRef always performs dense iteration
// But `Option<&Sparse>` will incorrectly report a component as never being present when doing dense iteration
// See https://github.com/bevyengine/bevy/issues/16397
assert!(query.is_dense);
let matched = query.iter(&world).filter(Option::is_some).count();
assert_eq!(matched, 0);
let mut query = QueryState::<EntityRef>::new(&mut world).transmute::<Has<Sparse>>(&world);
// EntityRef always performs dense iteration
// But `Has<Sparse>` will incorrectly report a component as never being present when doing dense iteration
// See https://github.com/bevyengine/bevy/issues/16397
assert!(query.is_dense);
let matched = query.iter(&world).filter(|&has| has).count();
assert_eq!(matched, 0);
}
#[test]
fn join() {
let mut world = World::new();
world.spawn(A(0));
world.spawn(B(1));
let entity_ab = world.spawn((A(2), B(3))).id();
world.spawn((A(4), B(5), C(6)));
let query_1 = QueryState::<&A, Without<C>>::new(&mut world);
let query_2 = QueryState::<&B, Without<C>>::new(&mut world);
let mut new_query: QueryState<Entity, ()> = query_1.join_filtered(&world, &query_2);
assert_eq!(new_query.single(&world).unwrap(), entity_ab);
}
#[test]
fn join_with_get() {
let mut world = World::new();
world.spawn(A(0));
world.spawn(B(1));
let entity_ab = world.spawn((A(2), B(3))).id();
let entity_abc = world.spawn((A(4), B(5), C(6))).id();
let query_1 = QueryState::<&A>::new(&mut world);
let query_2 = QueryState::<&B, Without<C>>::new(&mut world);
let mut new_query: QueryState<Entity, ()> = query_1.join_filtered(&world, &query_2);
assert!(new_query.get(&world, entity_ab).is_ok());
// should not be able to get entity with c.
assert!(new_query.get(&world, entity_abc).is_err());
}
#[test]
#[should_panic]
fn cannot_join_wrong_fetch() {
let mut world = World::new();
world.register_component::<C>();
let query_1 = QueryState::<&A>::new(&mut world);
let query_2 = QueryState::<&B>::new(&mut world);
let _query: QueryState<&C> = query_1.join(&world, &query_2);
}
#[test]
#[should_panic]
fn cannot_join_wrong_filter() {
let mut world = World::new();
let query_1 = QueryState::<&A, Without<C>>::new(&mut world);
let query_2 = QueryState::<&B, Without<C>>::new(&mut world);
let _: QueryState<Entity, Changed<C>> = query_1.join_filtered(&world, &query_2);
}
#[test]
#[should_panic]
fn cannot_join_mutable_after_readonly() {
let mut world = World::new();
// Calling this method would mean we had aliasing queries.
fn bad(_: Query<(&mut A, &mut B)>, _: Query<&A>) {}
world
.run_system_once(|query_a: Query<&mut A>, mut query_b: Query<&mut B>| {
let mut readonly = query_a.as_readonly();
let mut lens: QueryLens<(&mut A, &mut B)> = readonly.join(&mut query_b);
bad(lens.query(), query_a.as_readonly());
})
.unwrap();
}
#[test]
fn join_to_filtered_entity_mut() {
let mut world = World::new();
world.spawn((A(2), B(3)));
let query_1 = QueryState::<&mut A>::new(&mut world);
let query_2 = QueryState::<&mut B>::new(&mut world);
let mut new_query: QueryState<(Entity, FilteredEntityMut)> = query_1.join(&world, &query_2);
let (_entity, mut entity_mut) = new_query.single_mut(&mut world).unwrap();
assert!(entity_mut.get_mut::<A>().is_some());
assert!(entity_mut.get_mut::<B>().is_some());
}
#[test]
fn query_respects_default_filters() {
let mut world = World::new();
world.spawn((A(0), B(0), D));
world.spawn((B(0), C(0), D));
world.spawn((C(0), D));
world.register_disabling_component::<C>();
// Without<C> only matches the first entity
let mut query = QueryState::<&D>::new(&mut world);
assert_eq!(1, query.iter(&world).count());
// With<C> matches the last two entities
let mut query = QueryState::<&D, With<C>>::new(&mut world);
assert_eq!(2, query.iter(&world).count());
// Has should bypass the filter entirely
let mut query = QueryState::<(&D, Has<C>)>::new(&mut world);
assert_eq!(3, query.iter(&world).count());
// Allow should bypass the filter entirely
let mut query = QueryState::<&D, Allow<C>>::new(&mut world);
assert_eq!(3, query.iter(&world).count());
// Other filters should still be respected
let mut query = QueryState::<(&D, Has<C>), Without<B>>::new(&mut world);
assert_eq!(1, query.iter(&world).count());
}
#[derive(Component)]
struct Table;
#[derive(Component)]
#[component(storage = "SparseSet")]
struct Sparse;
#[derive(Component)]
struct Dummy;
#[test]
fn query_default_filters_updates_is_dense() {
let mut world = World::new();
world.spawn((Dummy, Table, Sparse));
world.spawn((Dummy, Table));
world.spawn((Dummy, Sparse));
let mut query = QueryState::<&Dummy>::new(&mut world);
// There are no sparse components involved thus the query is dense
assert!(query.is_dense);
assert_eq!(3, query.query(&world).count());
world.register_disabling_component::<Sparse>();
let mut query = QueryState::<&Dummy>::new(&mut world);
// The query doesn't ask for sparse components, but the default filters adds
// a sparse component thus it is NOT dense
assert!(!query.is_dense);
assert_eq!(1, query.query(&world).count());
let mut df = DefaultQueryFilters::from_world(&mut world);
df.register_disabling_component(world.register_component::<Table>());
world.insert_resource(df);
let mut query = QueryState::<&Dummy>::new(&mut world);
// If the filter is instead a table components, the query can still be dense
assert!(query.is_dense);
assert_eq!(1, query.query(&world).count());
let mut query = QueryState::<&Sparse>::new(&mut world);
// But only if the original query was dense
assert!(!query.is_dense);
assert_eq!(1, query.query(&world).count());
}
}
use crate::;
use crateUniqueEntityEquivalentSlice;
use Vec;
use DebugName;
use ;
use FixedBitSet;
use warn;
use Span;
use ;
/// An ID for either a table or an archetype. Used for Query iteration.
///
/// Query iteration is exclusively dense (over tables) or archetypal (over archetypes) based on whether
/// the query filters are dense or not. This is represented by the [`QueryState::is_dense`] field.
///
/// Note that `D::IS_DENSE` and `F::IS_DENSE` have no relationship with `QueryState::is_dense` and
/// any combination of their values can happen.
///
/// This is a union instead of an enum as the usage is determined at compile time, as all [`StorageId`]s for
/// a [`QueryState`] will be all [`TableId`]s or all [`ArchetypeId`]s, and not a mixture of both. This
/// removes the need for discriminator to minimize memory usage and branching during iteration, but requires
/// a safety invariant be verified when disambiguating them.
///
/// # Safety
/// Must be initialized and accessed as a [`TableId`], if both generic parameters to the query are dense.
/// Must be initialized and accessed as an [`ArchetypeId`] otherwise.
pub union StorageId
/// Provides scoped access to a [`World`] state according to a given [`QueryData`] and [`QueryFilter`].
///
/// This data is cached between system runs, and is used to:
/// - store metadata about which [`Table`] or [`Archetype`] are matched by the query. "Matched" means
/// that the query will iterate over the data in the matched table/archetype.
/// - cache the [`State`] needed to compute the [`Fetch`] struct used to retrieve data
/// from a specific [`Table`] or [`Archetype`]
/// - build iterators that can iterate over the query results
///
/// [`State`]: crate::query::world_query::WorldQuery::State
/// [`Fetch`]: crate::query::world_query::WorldQuery::Fetch
/// [`Table`]: crate::storage::Table
// SAFETY NOTE:
// Do not add any new fields that use the `D` or `F` generic parameters as this may
// make `QueryState::as_transmuted_state` unsound if not done with care.