bevy_ecs/query/par_iter.rs
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463
use crate::{
batching::BatchingStrategy,
component::Tick,
entity::{EntityEquivalent, UniqueEntityEquivalentVec},
world::unsafe_world_cell::UnsafeWorldCell,
};
use super::{QueryData, QueryFilter, QueryItem, QueryState, ReadOnlyQueryData};
use alloc::vec::Vec;
/// A parallel iterator over query results of a [`Query`](crate::system::Query).
///
/// This struct is created by the [`Query::par_iter`](crate::system::Query::par_iter) and
/// [`Query::par_iter_mut`](crate::system::Query::par_iter_mut) methods.
pub struct QueryParIter<'w, 's, D: QueryData, F: QueryFilter> {
pub(crate) world: UnsafeWorldCell<'w>,
pub(crate) state: &'s QueryState<D, F>,
pub(crate) last_run: Tick,
pub(crate) this_run: Tick,
pub(crate) batching_strategy: BatchingStrategy,
}
impl<'w, 's, D: QueryData, F: QueryFilter> QueryParIter<'w, 's, D, F> {
/// Changes the batching strategy used when iterating.
///
/// For more information on how this affects the resultant iteration, see
/// [`BatchingStrategy`].
pub fn batching_strategy(mut self, strategy: BatchingStrategy) -> Self {
self.batching_strategy = strategy;
self
}
/// Runs `func` on each query result in parallel.
///
/// # Panics
/// If 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.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn for_each<FN: Fn(QueryItem<'w, D>) + Send + Sync + Clone>(self, func: FN) {
self.for_each_init(|| {}, |_, item| func(item));
}
/// Runs `func` on each query result in parallel on a value returned by `init`.
///
/// `init` may be called multiple times per thread, and the values returned may be discarded between tasks on any given thread.
/// Callers should avoid using this function as if it were a parallel version
/// of [`Iterator::fold`].
///
/// # Example
///
/// ```
/// use bevy_utils::Parallel;
/// use crate::{bevy_ecs::prelude::Component, bevy_ecs::system::Query};
/// #[derive(Component)]
/// struct T;
/// fn system(query: Query<&T>){
/// let mut queue: Parallel<usize> = Parallel::default();
/// // queue.borrow_local_mut() will get or create a thread_local queue for each task/thread;
/// query.par_iter().for_each_init(|| queue.borrow_local_mut(),|local_queue, item| {
/// **local_queue += 1;
/// });
///
/// // collect value from every thread
/// let entity_count: usize = queue.iter_mut().map(|v| *v).sum();
/// }
/// ```
///
/// # Panics
/// If 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.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn for_each_init<FN, INIT, T>(self, init: INIT, func: FN)
where
FN: Fn(&mut T, QueryItem<'w, D>) + Send + Sync + Clone,
INIT: Fn() -> T + Sync + Send + Clone,
{
let func = |mut init, item| {
func(&mut init, item);
init
};
#[cfg(any(target_arch = "wasm32", not(feature = "multi_threaded")))]
{
let init = init();
// SAFETY:
// This method can only be called once per instance of QueryParIter,
// which ensures that mutable queries cannot be executed multiple times at once.
// Mutable instances of QueryParIter can only be created via an exclusive borrow of a
// Query or a World, which ensures that multiple aliasing QueryParIters cannot exist
// at the same time.
unsafe {
self.state
.query_unchecked_manual_with_ticks(self.world, self.last_run, self.this_run)
.into_iter()
.fold(init, func);
}
}
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
{
let thread_count = bevy_tasks::ComputeTaskPool::get().thread_num();
if thread_count <= 1 {
let init = init();
// SAFETY: See the safety comment above.
unsafe {
self.state
.query_unchecked_manual_with_ticks(self.world, self.last_run, self.this_run)
.into_iter()
.fold(init, func);
}
} else {
// Need a batch size of at least 1.
let batch_size = self.get_batch_size(thread_count).max(1);
// SAFETY: See the safety comment above.
unsafe {
self.state.par_fold_init_unchecked_manual(
init,
self.world,
batch_size,
func,
self.last_run,
self.this_run,
);
}
}
}
}
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
fn get_batch_size(&self, thread_count: usize) -> usize {
let max_items = || {
let id_iter = self.state.matched_storage_ids.iter();
if self.state.is_dense {
// SAFETY: We only access table metadata.
let tables = unsafe { &self.world.world_metadata().storages().tables };
id_iter
// SAFETY: The if check ensures that matched_storage_ids stores TableIds
.map(|id| unsafe { tables[id.table_id].entity_count() })
.max()
} else {
let archetypes = &self.world.archetypes();
id_iter
// SAFETY: The if check ensures that matched_storage_ids stores ArchetypeIds
.map(|id| unsafe { archetypes[id.archetype_id].len() })
.max()
}
.unwrap_or(0)
};
self.batching_strategy
.calc_batch_size(max_items, thread_count)
}
}
/// A parallel iterator over the unique query items generated from an [`Entity`] list.
///
/// This struct is created by the [`Query::par_iter_many`] method.
///
/// [`Entity`]: crate::entity::Entity
/// [`Query::par_iter_many`]: crate::system::Query::par_iter_many
pub struct QueryParManyIter<'w, 's, D: QueryData, F: QueryFilter, E: EntityEquivalent> {
pub(crate) world: UnsafeWorldCell<'w>,
pub(crate) state: &'s QueryState<D, F>,
pub(crate) entity_list: Vec<E>,
pub(crate) last_run: Tick,
pub(crate) this_run: Tick,
pub(crate) batching_strategy: BatchingStrategy,
}
impl<'w, 's, D: ReadOnlyQueryData, F: QueryFilter, E: EntityEquivalent + Sync>
QueryParManyIter<'w, 's, D, F, E>
{
/// Changes the batching strategy used when iterating.
///
/// For more information on how this affects the resultant iteration, see
/// [`BatchingStrategy`].
pub fn batching_strategy(mut self, strategy: BatchingStrategy) -> Self {
self.batching_strategy = strategy;
self
}
/// Runs `func` on each query result in parallel.
///
/// # Panics
/// If 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.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn for_each<FN: Fn(QueryItem<'w, D>) + Send + Sync + Clone>(self, func: FN) {
self.for_each_init(|| {}, |_, item| func(item));
}
/// Runs `func` on each query result in parallel on a value returned by `init`.
///
/// `init` may be called multiple times per thread, and the values returned may be discarded between tasks on any given thread.
/// Callers should avoid using this function as if it were a parallel version
/// of [`Iterator::fold`].
///
/// # Example
///
/// ```
/// use bevy_utils::Parallel;
/// use crate::{bevy_ecs::prelude::{Component, Res, Resource, Entity}, bevy_ecs::system::Query};
/// # use core::slice;
/// use bevy_platform::prelude::Vec;
/// # fn some_expensive_operation(_item: &T) -> usize {
/// # 0
/// # }
///
/// #[derive(Component)]
/// struct T;
///
/// #[derive(Resource)]
/// struct V(Vec<Entity>);
///
/// impl<'a> IntoIterator for &'a V {
/// // ...
/// # type Item = &'a Entity;
/// # type IntoIter = slice::Iter<'a, Entity>;
/// #
/// # fn into_iter(self) -> Self::IntoIter {
/// # self.0.iter()
/// # }
/// }
///
/// fn system(query: Query<&T>, entities: Res<V>){
/// let mut queue: Parallel<usize> = Parallel::default();
/// // queue.borrow_local_mut() will get or create a thread_local queue for each task/thread;
/// query.par_iter_many(&entities).for_each_init(|| queue.borrow_local_mut(),|local_queue, item| {
/// **local_queue += some_expensive_operation(item);
/// });
///
/// // collect value from every thread
/// let final_value: usize = queue.iter_mut().map(|v| *v).sum();
/// }
/// ```
///
/// # Panics
/// If 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.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn for_each_init<FN, INIT, T>(self, init: INIT, func: FN)
where
FN: Fn(&mut T, QueryItem<'w, D>) + Send + Sync + Clone,
INIT: Fn() -> T + Sync + Send + Clone,
{
let func = |mut init, item| {
func(&mut init, item);
init
};
#[cfg(any(target_arch = "wasm32", not(feature = "multi_threaded")))]
{
let init = init();
// SAFETY:
// This method can only be called once per instance of QueryParManyIter,
// which ensures that mutable queries cannot be executed multiple times at once.
// Mutable instances of QueryParManyUniqueIter can only be created via an exclusive borrow of a
// Query or a World, which ensures that multiple aliasing QueryParManyIters cannot exist
// at the same time.
unsafe {
self.state
.query_unchecked_manual_with_ticks(self.world, self.last_run, self.this_run)
.iter_many_inner(&self.entity_list)
.fold(init, func);
}
}
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
{
let thread_count = bevy_tasks::ComputeTaskPool::get().thread_num();
if thread_count <= 1 {
let init = init();
// SAFETY: See the safety comment above.
unsafe {
self.state
.query_unchecked_manual_with_ticks(self.world, self.last_run, self.this_run)
.iter_many_inner(&self.entity_list)
.fold(init, func);
}
} else {
// Need a batch size of at least 1.
let batch_size = self.get_batch_size(thread_count).max(1);
// SAFETY: See the safety comment above.
unsafe {
self.state.par_many_fold_init_unchecked_manual(
init,
self.world,
&self.entity_list,
batch_size,
func,
self.last_run,
self.this_run,
);
}
}
}
}
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
fn get_batch_size(&self, thread_count: usize) -> usize {
self.batching_strategy
.calc_batch_size(|| self.entity_list.len(), thread_count)
}
}
/// A parallel iterator over the unique query items generated from an [`EntitySet`].
///
/// This struct is created by the [`Query::par_iter_many_unique`] and [`Query::par_iter_many_unique_mut`] methods.
///
/// [`EntitySet`]: crate::entity::EntitySet
/// [`Query::par_iter_many_unique`]: crate::system::Query::par_iter_many_unique
/// [`Query::par_iter_many_unique_mut`]: crate::system::Query::par_iter_many_unique_mut
pub struct QueryParManyUniqueIter<'w, 's, D: QueryData, F: QueryFilter, E: EntityEquivalent + Sync>
{
pub(crate) world: UnsafeWorldCell<'w>,
pub(crate) state: &'s QueryState<D, F>,
pub(crate) entity_list: UniqueEntityEquivalentVec<E>,
pub(crate) last_run: Tick,
pub(crate) this_run: Tick,
pub(crate) batching_strategy: BatchingStrategy,
}
impl<'w, 's, D: QueryData, F: QueryFilter, E: EntityEquivalent + Sync>
QueryParManyUniqueIter<'w, 's, D, F, E>
{
/// Changes the batching strategy used when iterating.
///
/// For more information on how this affects the resultant iteration, see
/// [`BatchingStrategy`].
pub fn batching_strategy(mut self, strategy: BatchingStrategy) -> Self {
self.batching_strategy = strategy;
self
}
/// Runs `func` on each query result in parallel.
///
/// # Panics
/// If 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.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn for_each<FN: Fn(QueryItem<'w, D>) + Send + Sync + Clone>(self, func: FN) {
self.for_each_init(|| {}, |_, item| func(item));
}
/// Runs `func` on each query result in parallel on a value returned by `init`.
///
/// `init` may be called multiple times per thread, and the values returned may be discarded between tasks on any given thread.
/// Callers should avoid using this function as if it were a parallel version
/// of [`Iterator::fold`].
///
/// # Example
///
/// ```
/// use bevy_utils::Parallel;
/// use crate::{bevy_ecs::{prelude::{Component, Res, Resource, Entity}, entity::UniqueEntityVec, system::Query}};
/// # use core::slice;
/// # use crate::bevy_ecs::entity::UniqueEntityIter;
/// # fn some_expensive_operation(_item: &T) -> usize {
/// # 0
/// # }
///
/// #[derive(Component)]
/// struct T;
///
/// #[derive(Resource)]
/// struct V(UniqueEntityVec);
///
/// impl<'a> IntoIterator for &'a V {
/// // ...
/// # type Item = &'a Entity;
/// # type IntoIter = UniqueEntityIter<slice::Iter<'a, Entity>>;
/// #
/// # fn into_iter(self) -> Self::IntoIter {
/// # self.0.iter()
/// # }
/// }
///
/// fn system(query: Query<&T>, entities: Res<V>){
/// let mut queue: Parallel<usize> = Parallel::default();
/// // queue.borrow_local_mut() will get or create a thread_local queue for each task/thread;
/// query.par_iter_many_unique(&entities).for_each_init(|| queue.borrow_local_mut(),|local_queue, item| {
/// **local_queue += some_expensive_operation(item);
/// });
///
/// // collect value from every thread
/// let final_value: usize = queue.iter_mut().map(|v| *v).sum();
/// }
/// ```
///
/// # Panics
/// If 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.
///
/// [`ComputeTaskPool`]: bevy_tasks::ComputeTaskPool
#[inline]
pub fn for_each_init<FN, INIT, T>(self, init: INIT, func: FN)
where
FN: Fn(&mut T, QueryItem<'w, D>) + Send + Sync + Clone,
INIT: Fn() -> T + Sync + Send + Clone,
{
let func = |mut init, item| {
func(&mut init, item);
init
};
#[cfg(any(target_arch = "wasm32", not(feature = "multi_threaded")))]
{
let init = init();
// SAFETY:
// This method can only be called once per instance of QueryParManyUniqueIter,
// which ensures that mutable queries cannot be executed multiple times at once.
// Mutable instances of QueryParManyUniqueIter can only be created via an exclusive borrow of a
// Query or a World, which ensures that multiple aliasing QueryParManyUniqueIters cannot exist
// at the same time.
unsafe {
self.state
.query_unchecked_manual_with_ticks(self.world, self.last_run, self.this_run)
.iter_many_unique_inner(self.entity_list)
.fold(init, func);
}
}
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
{
let thread_count = bevy_tasks::ComputeTaskPool::get().thread_num();
if thread_count <= 1 {
let init = init();
// SAFETY: See the safety comment above.
unsafe {
self.state
.query_unchecked_manual_with_ticks(self.world, self.last_run, self.this_run)
.iter_many_unique_inner(self.entity_list)
.fold(init, func);
}
} else {
// Need a batch size of at least 1.
let batch_size = self.get_batch_size(thread_count).max(1);
// SAFETY: See the safety comment above.
unsafe {
self.state.par_many_unique_fold_init_unchecked_manual(
init,
self.world,
&self.entity_list,
batch_size,
func,
self.last_run,
self.this_run,
);
}
}
}
}
#[cfg(all(not(target_arch = "wasm32"), feature = "multi_threaded"))]
fn get_batch_size(&self, thread_count: usize) -> usize {
self.batching_strategy
.calc_batch_size(|| self.entity_list.len(), thread_count)
}
}