bevy/crates/bevy_ecs/src/bundle.rs
Alice Cecile ec7b3490f6
Add on_unimplemented Diagnostics to Most Public Traits (#13347) (#13662)
# Objective

- #13414 did not have the intended effect.
- #13404 is still blocked

## Solution

- Re-adds #13347.

Co-authored-by: Zachary Harrold <zac@harrold.com.au>
Co-authored-by: Jamie Ridding <Themayu@users.noreply.github.com>
Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
2024-06-04 00:31:34 +00:00

1238 lines
48 KiB
Rust

//! Types for handling [`Bundle`]s.
//!
//! This module contains the [`Bundle`] trait and some other helper types.
pub use bevy_ecs_macros::Bundle;
use bevy_utils::{HashMap, HashSet, TypeIdMap};
use crate::{
archetype::{
AddBundle, Archetype, ArchetypeId, Archetypes, BundleComponentStatus, ComponentStatus,
SpawnBundleStatus,
},
component::{Component, ComponentId, Components, StorageType, Tick},
entity::{Entities, Entity, EntityLocation},
prelude::World,
query::DebugCheckedUnwrap,
storage::{SparseSetIndex, SparseSets, Storages, Table, TableRow},
world::unsafe_world_cell::UnsafeWorldCell,
};
use bevy_ptr::{ConstNonNull, OwningPtr};
use bevy_utils::all_tuples;
use std::any::TypeId;
use std::ptr::NonNull;
/// The `Bundle` trait enables insertion and removal of [`Component`]s from an entity.
///
/// Implementors of the `Bundle` trait are called 'bundles'.
///
/// Each bundle represents a static set of [`Component`] types.
/// Currently, bundles can only contain one of each [`Component`], and will
/// panic once initialised if this is not met.
///
/// ## Insertion
///
/// The primary use for bundles is to add a useful collection of components to an entity.
///
/// Adding a value of bundle to an entity will add the components from the set it
/// represents to the entity.
/// The values of these components are taken from the bundle.
/// If an entity already had one of these components, the entity's original component value
/// will be overwritten.
///
/// Importantly, bundles are only their constituent set of components.
/// You **should not** use bundles as a unit of behavior.
/// The behavior of your app can only be considered in terms of components, as systems,
/// which drive the behavior of a `bevy` application, operate on combinations of
/// components.
///
/// This rule is also important because multiple bundles may contain the same component type,
/// calculated in different ways &mdash; adding both of these bundles to one entity
/// would create incoherent behavior.
/// This would be unexpected if bundles were treated as an abstraction boundary, as
/// the abstraction would be unmaintainable for these cases.
/// For example, both `Camera3dBundle` and `Camera2dBundle` contain the `CameraRenderGraph`
/// component, but specifying different render graphs to use.
/// If the bundles were both added to the same entity, only one of these two bundles would work.
///
/// For this reason, there is intentionally no [`Query`] to match whether an entity
/// contains the components of a bundle.
/// Queries should instead only select the components they logically operate on.
///
/// ## Removal
///
/// Bundles are also used when removing components from an entity.
///
/// Removing a bundle from an entity will remove any of its components attached
/// to the entity from the entity.
/// That is, if the entity does not have all the components of the bundle, those
/// which are present will be removed.
///
/// # Implementors
///
/// Every type which implements [`Component`] also implements `Bundle`, since
/// [`Component`] types can be added to or removed from an entity.
///
/// Additionally, [Tuples](`tuple`) of bundles are also [`Bundle`] (with up to 15 bundles).
/// These bundles contain the items of the 'inner' bundles.
/// This is a convenient shorthand which is primarily used when spawning entities.
/// For example, spawning an entity using the bundle `(SpriteBundle {...}, PlayerMarker)`
/// will spawn an entity with components required for a 2d sprite, and the `PlayerMarker` component.
///
/// [`unit`], otherwise known as [`()`](`unit`), is a [`Bundle`] containing no components (since it
/// can also be considered as the empty tuple).
/// This can be useful for spawning large numbers of empty entities using
/// [`World::spawn_batch`](crate::world::World::spawn_batch).
///
/// Tuple bundles can be nested, which can be used to create an anonymous bundle with more than
/// 15 items.
/// However, in most cases where this is required, the derive macro [`derive@Bundle`] should be
/// used instead.
/// The derived `Bundle` implementation contains the items of its fields, which all must
/// implement `Bundle`.
/// As explained above, this includes any [`Component`] type, and other derived bundles.
///
/// If you want to add `PhantomData` to your `Bundle` you have to mark it with `#[bundle(ignore)]`.
/// ```
/// # use std::marker::PhantomData;
/// use bevy_ecs::{component::Component, bundle::Bundle};
///
/// #[derive(Component)]
/// struct XPosition(i32);
/// #[derive(Component)]
/// struct YPosition(i32);
///
/// #[derive(Bundle)]
/// struct PositionBundle {
/// // A bundle can contain components
/// x: XPosition,
/// y: YPosition,
/// }
///
/// // You have to implement `Default` for ignored field types in bundle structs.
/// #[derive(Default)]
/// struct Other(f32);
///
/// #[derive(Bundle)]
/// struct NamedPointBundle<T: Send + Sync + 'static> {
/// // Or other bundles
/// a: PositionBundle,
/// // In addition to more components
/// z: PointName,
///
/// // when you need to use `PhantomData` you have to mark it as ignored
/// #[bundle(ignore)]
/// _phantom_data: PhantomData<T>
/// }
///
/// #[derive(Component)]
/// struct PointName(String);
/// ```
///
/// # Safety
///
/// Manual implementations of this trait are unsupported.
/// That is, there is no safe way to implement this trait, and you must not do so.
/// If you want a type to implement [`Bundle`], you must use [`derive@Bundle`](derive@Bundle).
///
/// [`Query`]: crate::system::Query
// Some safety points:
// - [`Bundle::component_ids`] must return the [`ComponentId`] for each component type in the
// bundle, in the _exact_ order that [`DynamicBundle::get_components`] is called.
// - [`Bundle::from_components`] must call `func` exactly once for each [`ComponentId`] returned by
// [`Bundle::component_ids`].
#[diagnostic::on_unimplemented(
message = "`{Self}` is not a `Bundle`",
label = "invalid `Bundle`",
note = "consider annotating `{Self}` with `#[derive(Component)]` or `#[derive(Bundle)]`"
)]
pub unsafe trait Bundle: DynamicBundle + Send + Sync + 'static {
/// Gets this [`Bundle`]'s component ids, in the order of this bundle's [`Component`]s
#[doc(hidden)]
fn component_ids(
components: &mut Components,
storages: &mut Storages,
ids: &mut impl FnMut(ComponentId),
);
/// Calls `func`, which should return data for each component in the bundle, in the order of
/// this bundle's [`Component`]s
///
/// # Safety
/// Caller must return data for each component in the bundle, in the order of this bundle's
/// [`Component`]s
#[doc(hidden)]
unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self
where
// Ensure that the `OwningPtr` is used correctly
F: for<'a> FnMut(&'a mut T) -> OwningPtr<'a>,
Self: Sized;
}
/// The parts from [`Bundle`] that don't require statically knowing the components of the bundle.
pub trait DynamicBundle {
// SAFETY:
// The `StorageType` argument passed into [`Bundle::get_components`] must be correct for the
// component being fetched.
//
/// Calls `func` on each value, in the order of this bundle's [`Component`]s. This passes
/// ownership of the component values to `func`.
#[doc(hidden)]
fn get_components(self, func: &mut impl FnMut(StorageType, OwningPtr<'_>));
}
// SAFETY:
// - `Bundle::component_ids` calls `ids` for C's component id (and nothing else)
// - `Bundle::get_components` is called exactly once for C and passes the component's storage type based on its associated constant.
// - `Bundle::from_components` calls `func` exactly once for C, which is the exact value returned by `Bundle::component_ids`.
unsafe impl<C: Component> Bundle for C {
fn component_ids(
components: &mut Components,
storages: &mut Storages,
ids: &mut impl FnMut(ComponentId),
) {
ids(components.init_component::<C>(storages));
}
unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self
where
// Ensure that the `OwningPtr` is used correctly
F: for<'a> FnMut(&'a mut T) -> OwningPtr<'a>,
Self: Sized,
{
let ptr = func(ctx);
// Safety: The id given in `component_ids` is for `Self`
unsafe { ptr.read() }
}
}
impl<C: Component> DynamicBundle for C {
#[inline]
fn get_components(self, func: &mut impl FnMut(StorageType, OwningPtr<'_>)) {
OwningPtr::make(self, |ptr| func(C::STORAGE_TYPE, ptr));
}
}
macro_rules! tuple_impl {
($($name: ident),*) => {
// SAFETY:
// - `Bundle::component_ids` calls `ids` for each component type in the
// bundle, in the exact order that `DynamicBundle::get_components` is called.
// - `Bundle::from_components` calls `func` exactly once for each `ComponentId` returned by `Bundle::component_ids`.
// - `Bundle::get_components` is called exactly once for each member. Relies on the above implementation to pass the correct
// `StorageType` into the callback.
unsafe impl<$($name: Bundle),*> Bundle for ($($name,)*) {
#[allow(unused_variables)]
fn component_ids(components: &mut Components, storages: &mut Storages, ids: &mut impl FnMut(ComponentId)){
$(<$name as Bundle>::component_ids(components, storages, ids);)*
}
#[allow(unused_variables, unused_mut)]
#[allow(clippy::unused_unit)]
unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self
where
F: FnMut(&mut T) -> OwningPtr<'_>
{
#[allow(unused_unsafe)]
// SAFETY: Rust guarantees that tuple calls are evaluated 'left to right'.
// https://doc.rust-lang.org/reference/expressions.html#evaluation-order-of-operands
unsafe { ($(<$name as Bundle>::from_components(ctx, func),)*) }
}
}
impl<$($name: Bundle),*> DynamicBundle for ($($name,)*) {
#[allow(unused_variables, unused_mut)]
#[inline(always)]
fn get_components(self, func: &mut impl FnMut(StorageType, OwningPtr<'_>)) {
#[allow(non_snake_case)]
let ($(mut $name,)*) = self;
$(
$name.get_components(&mut *func);
)*
}
}
}
}
all_tuples!(tuple_impl, 0, 15, B);
/// For a specific [`World`], this stores a unique value identifying a type of a registered [`Bundle`].
///
/// [`World`]: crate::world::World
#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
pub struct BundleId(usize);
impl BundleId {
/// Returns the index of the associated [`Bundle`] type.
///
/// Note that this is unique per-world, and should not be reused across them.
#[inline]
pub fn index(self) -> usize {
self.0
}
}
impl SparseSetIndex for BundleId {
#[inline]
fn sparse_set_index(&self) -> usize {
self.index()
}
#[inline]
fn get_sparse_set_index(value: usize) -> Self {
Self(value)
}
}
/// Stores metadata associated with a specific type of [`Bundle`] for a given [`World`].
///
/// [`World`]: crate::world::World
pub struct BundleInfo {
id: BundleId,
// SAFETY: Every ID in this list must be valid within the World that owns the BundleInfo,
// must have its storage initialized (i.e. columns created in tables, sparse set created),
// and must be in the same order as the source bundle type writes its components in.
component_ids: Vec<ComponentId>,
}
impl BundleInfo {
/// Create a new [`BundleInfo`].
///
/// # Safety
///
/// Every ID in `component_ids` must be valid within the World that owns the `BundleInfo`,
/// must have its storage initialized (i.e. columns created in tables, sparse set created),
/// and must be in the same order as the source bundle type writes its components in.
unsafe fn new(
bundle_type_name: &'static str,
components: &Components,
component_ids: Vec<ComponentId>,
id: BundleId,
) -> BundleInfo {
let mut deduped = component_ids.clone();
deduped.sort();
deduped.dedup();
if deduped.len() != component_ids.len() {
// TODO: Replace with `Vec::partition_dedup` once https://github.com/rust-lang/rust/issues/54279 is stabilized
let mut seen = HashSet::new();
let mut dups = Vec::new();
for id in component_ids {
if !seen.insert(id) {
dups.push(id);
}
}
let names = dups
.into_iter()
.map(|id| {
// SAFETY: the caller ensures component_id is valid.
unsafe { components.get_info_unchecked(id).name() }
})
.collect::<Vec<_>>()
.join(", ");
panic!("Bundle {bundle_type_name} has duplicate components: {names}");
}
// SAFETY: The caller ensures that component_ids:
// - is valid for the associated world
// - has had its storage initialized
// - is in the same order as the source bundle type
BundleInfo { id, component_ids }
}
/// Returns a value identifying the associated [`Bundle`] type.
#[inline]
pub const fn id(&self) -> BundleId {
self.id
}
/// Returns the [ID](ComponentId) of each component stored in this bundle.
#[inline]
pub fn components(&self) -> &[ComponentId] {
&self.component_ids
}
/// Returns an iterator over the [ID](ComponentId) of each component stored in this bundle.
#[inline]
pub fn iter_components(&self) -> impl Iterator<Item = ComponentId> + '_ {
self.component_ids.iter().cloned()
}
/// This writes components from a given [`Bundle`] to the given entity.
///
/// # Safety
///
/// `bundle_component_status` must return the "correct" [`ComponentStatus`] for each component
/// in the [`Bundle`], with respect to the entity's original archetype (prior to the bundle being added)
/// For example, if the original archetype already has `ComponentA` and `T` also has `ComponentA`, the status
/// should be `Mutated`. If the original archetype does not have `ComponentA`, the status should be `Added`.
/// When "inserting" a bundle into an existing entity, [`AddBundle`]
/// should be used, which will report `Added` vs `Mutated` status based on the current archetype's structure.
/// When spawning a bundle, [`SpawnBundleStatus`] can be used instead, which removes the need
/// to look up the [`AddBundle`] in the archetype graph, which requires
/// ownership of the entity's current archetype.
///
/// `table` must be the "new" table for `entity`. `table_row` must have space allocated for the
/// `entity`, `bundle` must match this [`BundleInfo`]'s type
#[inline]
#[allow(clippy::too_many_arguments)]
unsafe fn write_components<T: DynamicBundle, S: BundleComponentStatus>(
&self,
table: &mut Table,
sparse_sets: &mut SparseSets,
bundle_component_status: &S,
entity: Entity,
table_row: TableRow,
change_tick: Tick,
bundle: T,
) {
// NOTE: get_components calls this closure on each component in "bundle order".
// bundle_info.component_ids are also in "bundle order"
let mut bundle_component = 0;
bundle.get_components(&mut |storage_type, component_ptr| {
let component_id = *self.component_ids.get_unchecked(bundle_component);
match storage_type {
StorageType::Table => {
let column =
// SAFETY: If component_id is in self.component_ids, BundleInfo::new requires that
// the target table contains the component.
unsafe { table.get_column_mut(component_id).debug_checked_unwrap() };
// SAFETY: bundle_component is a valid index for this bundle
let status = unsafe { bundle_component_status.get_status(bundle_component) };
match status {
ComponentStatus::Added => {
column.initialize(table_row, component_ptr, change_tick);
}
ComponentStatus::Mutated => {
column.replace(table_row, component_ptr, change_tick);
}
}
}
StorageType::SparseSet => {
let sparse_set =
// SAFETY: If component_id is in self.component_ids, BundleInfo::new requires that
// a sparse set exists for the component.
unsafe { sparse_sets.get_mut(component_id).debug_checked_unwrap() };
sparse_set.insert(entity, component_ptr, change_tick);
}
}
bundle_component += 1;
});
}
/// Adds a bundle to the given archetype and returns the resulting archetype. This could be the
/// same [`ArchetypeId`], in the event that adding the given bundle does not result in an
/// [`Archetype`] change. Results are cached in the [`Archetype`] graph to avoid redundant work.
/// # Safety
/// `components` must be the same components as passed in [`Self::new`]
pub(crate) unsafe fn add_bundle_to_archetype(
&self,
archetypes: &mut Archetypes,
storages: &mut Storages,
components: &Components,
archetype_id: ArchetypeId,
) -> ArchetypeId {
if let Some(add_bundle_id) = archetypes[archetype_id].edges().get_add_bundle(self.id) {
return add_bundle_id;
}
let mut new_table_components = Vec::new();
let mut new_sparse_set_components = Vec::new();
let mut bundle_status = Vec::with_capacity(self.component_ids.len());
let current_archetype = &mut archetypes[archetype_id];
for component_id in self.component_ids.iter().cloned() {
if current_archetype.contains(component_id) {
bundle_status.push(ComponentStatus::Mutated);
} else {
bundle_status.push(ComponentStatus::Added);
// SAFETY: component_id exists
let component_info = unsafe { components.get_info_unchecked(component_id) };
match component_info.storage_type() {
StorageType::Table => new_table_components.push(component_id),
StorageType::SparseSet => new_sparse_set_components.push(component_id),
}
}
}
if new_table_components.is_empty() && new_sparse_set_components.is_empty() {
let edges = current_archetype.edges_mut();
// the archetype does not change when we add this bundle
edges.insert_add_bundle(self.id, archetype_id, bundle_status);
archetype_id
} else {
let table_id;
let table_components;
let sparse_set_components;
// the archetype changes when we add this bundle. prepare the new archetype and storages
{
let current_archetype = &archetypes[archetype_id];
table_components = if new_table_components.is_empty() {
// if there are no new table components, we can keep using this table
table_id = current_archetype.table_id();
current_archetype.table_components().collect()
} else {
new_table_components.extend(current_archetype.table_components());
// sort to ignore order while hashing
new_table_components.sort();
// SAFETY: all component ids in `new_table_components` exist
table_id = unsafe {
storages
.tables
.get_id_or_insert(&new_table_components, components)
};
new_table_components
};
sparse_set_components = if new_sparse_set_components.is_empty() {
current_archetype.sparse_set_components().collect()
} else {
new_sparse_set_components.extend(current_archetype.sparse_set_components());
// sort to ignore order while hashing
new_sparse_set_components.sort();
new_sparse_set_components
};
};
// SAFETY: ids in self must be valid
let new_archetype_id = archetypes.get_id_or_insert(
components,
table_id,
table_components,
sparse_set_components,
);
// add an edge from the old archetype to the new archetype
archetypes[archetype_id].edges_mut().insert_add_bundle(
self.id,
new_archetype_id,
bundle_status,
);
new_archetype_id
}
}
}
// SAFETY: We have exclusive world access so our pointers can't be invalidated externally
pub(crate) struct BundleInserter<'w> {
world: UnsafeWorldCell<'w>,
bundle_info: ConstNonNull<BundleInfo>,
add_bundle: ConstNonNull<AddBundle>,
table: NonNull<Table>,
archetype: NonNull<Archetype>,
result: InsertBundleResult,
change_tick: Tick,
}
pub(crate) enum InsertBundleResult {
SameArchetype,
NewArchetypeSameTable {
new_archetype: NonNull<Archetype>,
},
NewArchetypeNewTable {
new_archetype: NonNull<Archetype>,
new_table: NonNull<Table>,
},
}
impl<'w> BundleInserter<'w> {
#[inline]
pub(crate) fn new<T: Bundle>(
world: &'w mut World,
archetype_id: ArchetypeId,
change_tick: Tick,
) -> Self {
let bundle_id = world
.bundles
.init_info::<T>(&mut world.components, &mut world.storages);
// SAFETY: We just ensured this bundle exists
unsafe { Self::new_with_id(world, archetype_id, bundle_id, change_tick) }
}
/// Creates a new [`BundleInserter`].
///
/// # Safety
/// - Caller must ensure that `bundle_id` exists in `world.bundles`.
#[inline]
pub(crate) unsafe fn new_with_id(
world: &'w mut World,
archetype_id: ArchetypeId,
bundle_id: BundleId,
change_tick: Tick,
) -> Self {
// SAFETY: We will not make any accesses to the command queue, component or resource data of this world
let bundle_info = world.bundles.get_unchecked(bundle_id);
let bundle_id = bundle_info.id();
let new_archetype_id = bundle_info.add_bundle_to_archetype(
&mut world.archetypes,
&mut world.storages,
&world.components,
archetype_id,
);
if new_archetype_id == archetype_id {
let archetype = &mut world.archetypes[archetype_id];
// SAFETY: The edge is assured to be initialized when we called add_bundle_to_archetype
let add_bundle = unsafe {
archetype
.edges()
.get_add_bundle_internal(bundle_id)
.debug_checked_unwrap()
};
let table_id = archetype.table_id();
let table = &mut world.storages.tables[table_id];
Self {
add_bundle: add_bundle.into(),
archetype: archetype.into(),
bundle_info: bundle_info.into(),
table: table.into(),
result: InsertBundleResult::SameArchetype,
change_tick,
world: world.as_unsafe_world_cell(),
}
} else {
let (archetype, new_archetype) =
world.archetypes.get_2_mut(archetype_id, new_archetype_id);
// SAFETY: The edge is assured to be initialized when we called add_bundle_to_archetype
let add_bundle = unsafe {
archetype
.edges()
.get_add_bundle_internal(bundle_id)
.debug_checked_unwrap()
};
let table_id = archetype.table_id();
let new_table_id = new_archetype.table_id();
if table_id == new_table_id {
let table = &mut world.storages.tables[table_id];
Self {
add_bundle: add_bundle.into(),
archetype: archetype.into(),
bundle_info: bundle_info.into(),
table: table.into(),
result: InsertBundleResult::NewArchetypeSameTable {
new_archetype: new_archetype.into(),
},
change_tick,
world: world.as_unsafe_world_cell(),
}
} else {
let (table, new_table) = world.storages.tables.get_2_mut(table_id, new_table_id);
Self {
add_bundle: add_bundle.into(),
archetype: archetype.into(),
bundle_info: bundle_info.into(),
table: table.into(),
result: InsertBundleResult::NewArchetypeNewTable {
new_archetype: new_archetype.into(),
new_table: new_table.into(),
},
change_tick,
world: world.as_unsafe_world_cell(),
}
}
}
}
/// # Safety
/// `entity` must currently exist in the source archetype for this inserter. `location`
/// must be `entity`'s location in the archetype. `T` must match this [`BundleInfo`]'s type
#[inline]
pub(crate) unsafe fn insert<T: DynamicBundle>(
&mut self,
entity: Entity,
location: EntityLocation,
bundle: T,
) -> EntityLocation {
let bundle_info = self.bundle_info.as_ref();
let add_bundle = self.add_bundle.as_ref();
let table = self.table.as_mut();
let archetype = self.archetype.as_mut();
let (new_archetype, new_location) = match &mut self.result {
InsertBundleResult::SameArchetype => {
// SAFETY: Mutable references do not alias and will be dropped after this block
let sparse_sets = {
let world = self.world.world_mut();
&mut world.storages.sparse_sets
};
bundle_info.write_components(
table,
sparse_sets,
add_bundle,
entity,
location.table_row,
self.change_tick,
bundle,
);
(archetype, location)
}
InsertBundleResult::NewArchetypeSameTable { new_archetype } => {
let new_archetype = new_archetype.as_mut();
// SAFETY: Mutable references do not alias and will be dropped after this block
let (sparse_sets, entities) = {
let world = self.world.world_mut();
(&mut world.storages.sparse_sets, &mut world.entities)
};
let result = archetype.swap_remove(location.archetype_row);
if let Some(swapped_entity) = result.swapped_entity {
let swapped_location =
// SAFETY: If the swap was successful, swapped_entity must be valid.
unsafe { entities.get(swapped_entity).debug_checked_unwrap() };
entities.set(
swapped_entity.index(),
EntityLocation {
archetype_id: swapped_location.archetype_id,
archetype_row: location.archetype_row,
table_id: swapped_location.table_id,
table_row: swapped_location.table_row,
},
);
}
let new_location = new_archetype.allocate(entity, result.table_row);
entities.set(entity.index(), new_location);
bundle_info.write_components(
table,
sparse_sets,
add_bundle,
entity,
result.table_row,
self.change_tick,
bundle,
);
(new_archetype, new_location)
}
InsertBundleResult::NewArchetypeNewTable {
new_archetype,
new_table,
} => {
let new_table = new_table.as_mut();
let new_archetype = new_archetype.as_mut();
// SAFETY: Mutable references do not alias and will be dropped after this block
let (archetypes_ptr, sparse_sets, entities) = {
let world = self.world.world_mut();
let archetype_ptr: *mut Archetype = world.archetypes.archetypes.as_mut_ptr();
(
archetype_ptr,
&mut world.storages.sparse_sets,
&mut world.entities,
)
};
let result = archetype.swap_remove(location.archetype_row);
if let Some(swapped_entity) = result.swapped_entity {
let swapped_location =
// SAFETY: If the swap was successful, swapped_entity must be valid.
unsafe { entities.get(swapped_entity).debug_checked_unwrap() };
entities.set(
swapped_entity.index(),
EntityLocation {
archetype_id: swapped_location.archetype_id,
archetype_row: location.archetype_row,
table_id: swapped_location.table_id,
table_row: swapped_location.table_row,
},
);
}
// PERF: store "non bundle" components in edge, then just move those to avoid
// redundant copies
let move_result = table.move_to_superset_unchecked(result.table_row, new_table);
let new_location = new_archetype.allocate(entity, move_result.new_row);
entities.set(entity.index(), new_location);
// if an entity was moved into this entity's table spot, update its table row
if let Some(swapped_entity) = move_result.swapped_entity {
let swapped_location =
// SAFETY: If the swap was successful, swapped_entity must be valid.
unsafe { entities.get(swapped_entity).debug_checked_unwrap() };
entities.set(
swapped_entity.index(),
EntityLocation {
archetype_id: swapped_location.archetype_id,
archetype_row: swapped_location.archetype_row,
table_id: swapped_location.table_id,
table_row: result.table_row,
},
);
if archetype.id() == swapped_location.archetype_id {
archetype
.set_entity_table_row(swapped_location.archetype_row, result.table_row);
} else if new_archetype.id() == swapped_location.archetype_id {
new_archetype
.set_entity_table_row(swapped_location.archetype_row, result.table_row);
} else {
// SAFETY: the only two borrowed archetypes are above and we just did collision checks
(*archetypes_ptr.add(swapped_location.archetype_id.index()))
.set_entity_table_row(swapped_location.archetype_row, result.table_row);
}
}
bundle_info.write_components(
new_table,
sparse_sets,
add_bundle,
entity,
move_result.new_row,
self.change_tick,
bundle,
);
(new_archetype, new_location)
}
};
// SAFETY: We have no outstanding mutable references to world as they were dropped
let mut deferred_world = unsafe { self.world.into_deferred() };
if new_archetype.has_on_add() {
// SAFETY: All components in the bundle are guaranteed to exist in the World
// as they must be initialized before creating the BundleInfo.
unsafe {
deferred_world.trigger_on_add(
entity,
bundle_info
.iter_components()
.zip(add_bundle.bundle_status.iter())
.filter(|(_, &status)| status == ComponentStatus::Added)
.map(|(id, _)| id),
);
}
}
if new_archetype.has_on_insert() {
// SAFETY: All components in the bundle are guaranteed to exist in the World
// as they must be initialized before creating the BundleInfo.
unsafe { deferred_world.trigger_on_insert(entity, bundle_info.iter_components()) }
}
new_location
}
#[inline]
pub(crate) fn entities(&mut self) -> &mut Entities {
// SAFETY: No outstanding references to self.world, changes to entities cannot invalidate our internal pointers
unsafe { &mut self.world.world_mut().entities }
}
}
// SAFETY: We have exclusive world access so our pointers can't be invalidated externally
pub(crate) struct BundleSpawner<'w> {
world: UnsafeWorldCell<'w>,
bundle_info: ConstNonNull<BundleInfo>,
table: NonNull<Table>,
archetype: NonNull<Archetype>,
change_tick: Tick,
}
impl<'w> BundleSpawner<'w> {
#[inline]
pub fn new<T: Bundle>(world: &'w mut World, change_tick: Tick) -> Self {
let bundle_id = world
.bundles
.init_info::<T>(&mut world.components, &mut world.storages);
// SAFETY: we initialized this bundle_id in `init_info`
unsafe { Self::new_with_id(world, bundle_id, change_tick) }
}
/// Creates a new [`BundleSpawner`].
///
/// # Safety
/// Caller must ensure that `bundle_id` exists in `world.bundles`
#[inline]
pub(crate) unsafe fn new_with_id(
world: &'w mut World,
bundle_id: BundleId,
change_tick: Tick,
) -> Self {
let bundle_info = world.bundles.get_unchecked(bundle_id);
let new_archetype_id = bundle_info.add_bundle_to_archetype(
&mut world.archetypes,
&mut world.storages,
&world.components,
ArchetypeId::EMPTY,
);
let archetype = &mut world.archetypes[new_archetype_id];
let table = &mut world.storages.tables[archetype.table_id()];
Self {
bundle_info: bundle_info.into(),
table: table.into(),
archetype: archetype.into(),
change_tick,
world: world.as_unsafe_world_cell(),
}
}
#[inline]
pub fn reserve_storage(&mut self, additional: usize) {
// SAFETY: There are no outstanding world references
let (archetype, table) = unsafe { (self.archetype.as_mut(), self.table.as_mut()) };
archetype.reserve(additional);
table.reserve(additional);
}
/// # Safety
/// `entity` must be allocated (but non-existent), `T` must match this [`BundleInfo`]'s type
#[inline]
pub unsafe fn spawn_non_existent<T: DynamicBundle>(
&mut self,
entity: Entity,
bundle: T,
) -> EntityLocation {
let table = self.table.as_mut();
let archetype = self.archetype.as_mut();
let bundle_info = self.bundle_info.as_ref();
// SAFETY: We do not make any structural changes to the archetype graph through self.world so this pointer always remain valid
let location = {
// SAFETY: Mutable references do not alias and will be dropped after this block
let (sparse_sets, entities) = {
let world = self.world.world_mut();
(&mut world.storages.sparse_sets, &mut world.entities)
};
let table_row = table.allocate(entity);
let location = archetype.allocate(entity, table_row);
bundle_info.write_components(
table,
sparse_sets,
&SpawnBundleStatus,
entity,
table_row,
self.change_tick,
bundle,
);
entities.set(entity.index(), location);
location
};
// SAFETY: We have no outstanding mutable references to world as they were dropped
let mut deferred_world = unsafe { self.world.into_deferred() };
if archetype.has_on_add() {
// SAFETY: All components in the bundle are guaranteed to exist in the World
// as they must be initialized before creating the BundleInfo.
unsafe { deferred_world.trigger_on_add(entity, bundle_info.iter_components()) };
}
if archetype.has_on_insert() {
// SAFETY: All components in the bundle are guaranteed to exist in the World
// as they must be initialized before creating the BundleInfo.
unsafe { deferred_world.trigger_on_insert(entity, bundle_info.iter_components()) };
}
location
}
/// # Safety
/// `T` must match this [`BundleInfo`]'s type
#[inline]
pub unsafe fn spawn<T: Bundle>(&mut self, bundle: T) -> Entity {
let entity = self.entities().alloc();
// SAFETY: entity is allocated (but non-existent), `T` matches this BundleInfo's type
unsafe {
self.spawn_non_existent(entity, bundle);
}
entity
}
#[inline]
pub(crate) fn entities(&mut self) -> &mut Entities {
// SAFETY: No outstanding references to self.world, changes to entities cannot invalidate our internal pointers
unsafe { &mut self.world.world_mut().entities }
}
/// # Safety:
/// - `Self` must be dropped after running this function as it may invalidate internal pointers.
#[inline]
pub(crate) unsafe fn flush_commands(&mut self) {
// SAFETY: pointers on self can be invalidated,
self.world.world_mut().flush_commands();
}
}
/// Metadata for bundles. Stores a [`BundleInfo`] for each type of [`Bundle`] in a given world.
#[derive(Default)]
pub struct Bundles {
bundle_infos: Vec<BundleInfo>,
/// Cache static [`BundleId`]
bundle_ids: TypeIdMap<BundleId>,
/// Cache dynamic [`BundleId`] with multiple components
dynamic_bundle_ids: HashMap<Box<[ComponentId]>, BundleId>,
dynamic_bundle_storages: HashMap<BundleId, Vec<StorageType>>,
/// Cache optimized dynamic [`BundleId`] with single component
dynamic_component_bundle_ids: HashMap<ComponentId, BundleId>,
dynamic_component_storages: HashMap<BundleId, StorageType>,
}
impl Bundles {
/// Gets the metadata associated with a specific type of bundle.
/// Returns `None` if the bundle is not registered with the world.
#[inline]
pub fn get(&self, bundle_id: BundleId) -> Option<&BundleInfo> {
self.bundle_infos.get(bundle_id.index())
}
/// Gets the value identifying a specific type of bundle.
/// Returns `None` if the bundle does not exist in the world,
/// or if `type_id` does not correspond to a type of bundle.
#[inline]
pub fn get_id(&self, type_id: TypeId) -> Option<BundleId> {
self.bundle_ids.get(&type_id).cloned()
}
/// Initializes a new [`BundleInfo`] for a statically known type.
///
/// Also initializes all the components in the bundle.
pub(crate) fn init_info<T: Bundle>(
&mut self,
components: &mut Components,
storages: &mut Storages,
) -> BundleId {
let bundle_infos = &mut self.bundle_infos;
let id = *self.bundle_ids.entry(TypeId::of::<T>()).or_insert_with(|| {
let mut component_ids = Vec::new();
T::component_ids(components, storages, &mut |id| component_ids.push(id));
let id = BundleId(bundle_infos.len());
let bundle_info =
// SAFETY: T::component_id ensures:
// - its info was created
// - appropriate storage for it has been initialized.
// - it was created in the same order as the components in T
unsafe { BundleInfo::new(std::any::type_name::<T>(), components, component_ids, id) };
bundle_infos.push(bundle_info);
id
});
id
}
/// # Safety
/// A `BundleInfo` with the given `BundleId` must have been initialized for this instance of `Bundles`.
pub(crate) unsafe fn get_unchecked(&self, id: BundleId) -> &BundleInfo {
self.bundle_infos.get_unchecked(id.0)
}
pub(crate) unsafe fn get_storage_unchecked(&self, id: BundleId) -> StorageType {
*self
.dynamic_component_storages
.get(&id)
.debug_checked_unwrap()
}
pub(crate) unsafe fn get_storages_unchecked(&mut self, id: BundleId) -> &mut Vec<StorageType> {
self.dynamic_bundle_storages
.get_mut(&id)
.debug_checked_unwrap()
}
/// Initializes a new [`BundleInfo`] for a dynamic [`Bundle`].
///
/// # Panics
///
/// Panics if any of the provided [`ComponentId`]s do not exist in the
/// provided [`Components`].
pub(crate) fn init_dynamic_info(
&mut self,
components: &Components,
component_ids: &[ComponentId],
) -> BundleId {
let bundle_infos = &mut self.bundle_infos;
// Use `raw_entry_mut` to avoid cloning `component_ids` to access `Entry`
let (_, bundle_id) = self
.dynamic_bundle_ids
.raw_entry_mut()
.from_key(component_ids)
.or_insert_with(|| {
let (id, storages) =
initialize_dynamic_bundle(bundle_infos, components, Vec::from(component_ids));
self.dynamic_bundle_storages
.insert_unique_unchecked(id, storages);
(component_ids.into(), id)
});
*bundle_id
}
/// Initializes a new [`BundleInfo`] for a dynamic [`Bundle`] with single component.
///
/// # Panics
///
/// Panics if the provided [`ComponentId`] does not exist in the provided [`Components`].
pub(crate) fn init_component_info(
&mut self,
components: &Components,
component_id: ComponentId,
) -> BundleId {
let bundle_infos = &mut self.bundle_infos;
let bundle_id = self
.dynamic_component_bundle_ids
.entry(component_id)
.or_insert_with(|| {
let (id, storage_type) =
initialize_dynamic_bundle(bundle_infos, components, vec![component_id]);
self.dynamic_component_storages.insert(id, storage_type[0]);
id
});
*bundle_id
}
}
/// Asserts that all components are part of [`Components`]
/// and initializes a [`BundleInfo`].
fn initialize_dynamic_bundle(
bundle_infos: &mut Vec<BundleInfo>,
components: &Components,
component_ids: Vec<ComponentId>,
) -> (BundleId, Vec<StorageType>) {
// Assert component existence
let storage_types = component_ids.iter().map(|&id| {
components.get_info(id).unwrap_or_else(|| {
panic!(
"init_dynamic_info called with component id {id:?} which doesn't exist in this world"
)
}).storage_type()
}).collect();
let id = BundleId(bundle_infos.len());
let bundle_info =
// SAFETY: `component_ids` are valid as they were just checked
unsafe { BundleInfo::new("<dynamic bundle>", components, component_ids, id) };
bundle_infos.push(bundle_info);
(id, storage_types)
}
#[cfg(test)]
mod tests {
use crate as bevy_ecs;
use crate::prelude::*;
#[derive(Component)]
struct A;
#[derive(Component)]
struct B;
#[derive(Component)]
struct C;
#[derive(Component)]
struct D;
#[derive(Resource, Default)]
struct R(usize);
impl R {
#[track_caller]
fn assert_order(&mut self, count: usize) {
assert_eq!(count, self.0);
self.0 += 1;
}
}
#[test]
fn component_hook_order_spawn_despawn() {
let mut world = World::new();
world.init_resource::<R>();
world
.register_component_hooks::<A>()
.on_add(|mut world, _, _| {
world.resource_mut::<R>().assert_order(0);
})
.on_insert(|mut world, _, _| world.resource_mut::<R>().assert_order(1))
.on_remove(|mut world, _, _| world.resource_mut::<R>().assert_order(2));
let entity = world.spawn(A).id();
world.despawn(entity);
assert_eq!(3, world.resource::<R>().0);
}
#[test]
fn component_hook_order_insert_remove() {
let mut world = World::new();
world.init_resource::<R>();
world
.register_component_hooks::<A>()
.on_add(|mut world, _, _| {
world.resource_mut::<R>().assert_order(0);
})
.on_insert(|mut world, _, _| {
world.resource_mut::<R>().assert_order(1);
})
.on_remove(|mut world, _, _| {
world.resource_mut::<R>().assert_order(2);
});
let mut entity = world.spawn_empty();
entity.insert(A);
entity.remove::<A>();
entity.flush();
assert_eq!(3, world.resource::<R>().0);
}
#[test]
fn component_hook_order_recursive() {
let mut world = World::new();
world.init_resource::<R>();
world
.register_component_hooks::<A>()
.on_add(|mut world, entity, _| {
world.resource_mut::<R>().assert_order(0);
world.commands().entity(entity).insert(B);
})
.on_remove(|mut world, entity, _| {
world.resource_mut::<R>().assert_order(2);
world.commands().entity(entity).remove::<B>();
});
world
.register_component_hooks::<B>()
.on_add(|mut world, entity, _| {
world.resource_mut::<R>().assert_order(1);
world.commands().entity(entity).remove::<A>();
})
.on_remove(|mut world, _, _| {
world.resource_mut::<R>().assert_order(3);
});
let entity = world.spawn(A).flush();
let entity = world.get_entity(entity).unwrap();
assert!(!entity.contains::<A>());
assert!(!entity.contains::<B>());
assert_eq!(4, world.resource::<R>().0);
}
#[test]
fn component_hook_order_recursive_multiple() {
let mut world = World::new();
world.init_resource::<R>();
world
.register_component_hooks::<A>()
.on_add(|mut world, entity, _| {
world.resource_mut::<R>().assert_order(0);
world.commands().entity(entity).insert(B).insert(C);
});
world
.register_component_hooks::<B>()
.on_add(|mut world, entity, _| {
world.resource_mut::<R>().assert_order(1);
world.commands().entity(entity).insert(D);
});
world
.register_component_hooks::<C>()
.on_add(|mut world, _, _| {
world.resource_mut::<R>().assert_order(2);
});
world
.register_component_hooks::<D>()
.on_add(|mut world, _, _| {
world.resource_mut::<R>().assert_order(3);
});
world.spawn(A).flush();
assert_eq!(4, world.resource::<R>().0);
}
}