959 lines
34 KiB
Rust
959 lines
34 KiB
Rust
use crate::{
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component::{ComponentId, ComponentInfo, ComponentTicks, Components, Tick, TickCells},
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entity::Entity,
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query::DebugCheckedUnwrap,
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storage::{blob_vec::BlobVec, ImmutableSparseSet, SparseSet},
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};
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use bevy_ptr::{OwningPtr, Ptr, PtrMut, UnsafeCellDeref};
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use bevy_utils::HashMap;
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use std::alloc::Layout;
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use std::{
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cell::UnsafeCell,
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ops::{Index, IndexMut},
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};
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/// An opaque unique ID for a [`Table`] within a [`World`].
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///
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/// Can be used with [`Tables::get`] to fetch the corresponding
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/// table.
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///
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/// Each [`Archetype`] always points to a table via [`Archetype::table_id`].
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/// Multiple archetypes can point to the same table so long as the components
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/// stored in the table are identical, but do not share the same sparse set
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/// components.
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///
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/// [`World`]: crate::world::World
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/// [`Archetype`]: crate::archetype::Archetype
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/// [`Archetype::table_id`]: crate::archetype::Archetype::table_id
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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// SAFETY: Must be repr(transparent) due to the safety requirements on EntityLocation
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#[repr(transparent)]
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pub struct TableId(u32);
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impl TableId {
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pub(crate) const INVALID: TableId = TableId(u32::MAX);
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/// Creates a new [`TableId`].
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///
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/// `index` *must* be retrieved from calling [`TableId::as_u32`] on a `TableId` you got
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/// from a table of a given [`World`] or the created ID may be invalid.
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///
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/// [`World`]: crate::world::World
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#[inline]
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pub const fn from_u32(index: u32) -> Self {
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Self(index)
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}
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/// Creates a new [`TableId`].
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///
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/// `index` *must* be retrieved from calling [`TableId::as_usize`] on a `TableId` you got
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/// from a table of a given [`World`] or the created ID may be invalid.
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///
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/// [`World`]: crate::world::World
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///
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/// # Panics
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///
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/// Will panic if the provided value does not fit within a [`u32`].
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#[inline]
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pub const fn from_usize(index: usize) -> Self {
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debug_assert!(index as u32 as usize == index);
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Self(index as u32)
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}
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/// Gets the underlying table index from the ID.
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#[inline]
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pub const fn as_u32(self) -> u32 {
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self.0
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}
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/// Gets the underlying table index from the ID.
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#[inline]
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pub const fn as_usize(self) -> usize {
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// usize is at least u32 in Bevy
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self.0 as usize
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}
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/// The [`TableId`] of the [`Table`] without any components.
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#[inline]
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pub const fn empty() -> Self {
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Self(0)
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}
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}
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/// A opaque newtype for rows in [`Table`]s. Specifies a single row in a specific table.
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///
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/// Values of this type are retrievable from [`Archetype::entity_table_row`] and can be
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/// used alongside [`Archetype::table_id`] to fetch the exact table and row where an
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/// [`Entity`]'s
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///
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/// Values of this type are only valid so long as entities have not moved around.
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/// Adding and removing components from an entity, or despawning it will invalidate
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/// potentially any table row in the table the entity was previously stored in. Users
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/// should *always* fetch the appropriate row from the entity's [`Archetype`] before
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/// fetching the entity's components.
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///
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/// [`Archetype`]: crate::archetype::Archetype
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/// [`Archetype::entity_table_row`]: crate::archetype::Archetype::entity_table_row
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/// [`Archetype::table_id`]: crate::archetype::Archetype::table_id
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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// SAFETY: Must be repr(transparent) due to the safety requirements on EntityLocation
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#[repr(transparent)]
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pub struct TableRow(u32);
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impl TableRow {
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pub(crate) const INVALID: TableRow = TableRow(u32::MAX);
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/// Creates a `TableRow`.
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#[inline]
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pub const fn from_u32(index: u32) -> Self {
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Self(index)
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}
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/// Creates a `TableRow` from a [`usize`] index.
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///
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/// # Panics
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///
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/// Will panic if the provided value does not fit within a [`u32`].
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#[inline]
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pub const fn from_usize(index: usize) -> Self {
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debug_assert!(index as u32 as usize == index);
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Self(index as u32)
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}
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/// Gets the index of the row as a [`usize`].
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#[inline]
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pub const fn as_usize(self) -> usize {
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// usize is at least u32 in Bevy
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self.0 as usize
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}
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/// Gets the index of the row as a [`usize`].
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#[inline]
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pub const fn as_u32(self) -> u32 {
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self.0
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}
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}
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/// A type-erased contiguous container for data of a homogeneous type.
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///
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/// Conceptually, a [`Column`] is very similar to a type-erased `Vec<T>`.
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/// It also stores the change detection ticks for its components, kept in two separate
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/// contiguous buffers internally. An element shares its data across these buffers by using the
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/// same index (i.e. the entity at row 3 has its data at index 3 and its change detection ticks at
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/// index 3). A slice to these contiguous blocks of memory can be fetched
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/// via [`Column::get_data_slice`], [`Column::get_added_ticks_slice`], and
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/// [`Column::get_changed_ticks_slice`].
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///
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/// Like many other low-level storage types, [`Column`] has a limited and highly unsafe
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/// interface. It's highly advised to use higher level types and their safe abstractions
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/// instead of working directly with [`Column`].
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#[derive(Debug)]
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pub struct Column {
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data: BlobVec,
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added_ticks: Vec<UnsafeCell<Tick>>,
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changed_ticks: Vec<UnsafeCell<Tick>>,
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}
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impl Column {
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/// Constructs a new [`Column`], configured with a component's layout and an initial `capacity`.
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#[inline]
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pub(crate) fn with_capacity(component_info: &ComponentInfo, capacity: usize) -> Self {
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Column {
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// SAFETY: component_info.drop() is valid for the types that will be inserted.
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data: unsafe { BlobVec::new(component_info.layout(), component_info.drop(), capacity) },
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added_ticks: Vec::with_capacity(capacity),
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changed_ticks: Vec::with_capacity(capacity),
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}
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}
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/// Fetches the [`Layout`] for the underlying type.
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#[inline]
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pub fn item_layout(&self) -> Layout {
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self.data.layout()
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}
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/// Writes component data to the column at given row.
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/// Assumes the slot is uninitialized, drop is not called.
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/// To overwrite existing initialized value, use `replace` instead.
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///
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/// # Safety
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/// Assumes data has already been allocated for the given row.
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#[inline]
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pub(crate) unsafe fn initialize(&mut self, row: TableRow, data: OwningPtr<'_>, tick: Tick) {
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debug_assert!(row.as_usize() < self.len());
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self.data.initialize_unchecked(row.as_usize(), data);
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*self.added_ticks.get_unchecked_mut(row.as_usize()).get_mut() = tick;
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*self
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.changed_ticks
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.get_unchecked_mut(row.as_usize())
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.get_mut() = tick;
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}
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/// Writes component data to the column at given row.
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/// Assumes the slot is initialized, calls drop.
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///
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/// # Safety
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/// Assumes data has already been allocated for the given row.
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#[inline]
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pub(crate) unsafe fn replace(&mut self, row: TableRow, data: OwningPtr<'_>, change_tick: Tick) {
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debug_assert!(row.as_usize() < self.len());
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self.data.replace_unchecked(row.as_usize(), data);
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*self
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.changed_ticks
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.get_unchecked_mut(row.as_usize())
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.get_mut() = change_tick;
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}
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/// Gets the current number of elements stored in the column.
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#[inline]
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pub fn len(&self) -> usize {
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self.data.len()
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}
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/// Checks if the column is empty. Returns `true` if there are no elements, `false` otherwise.
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#[inline]
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pub fn is_empty(&self) -> bool {
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self.data.is_empty()
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}
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/// Removes an element from the [`Column`].
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///
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/// - The value will be dropped if it implements [`Drop`].
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/// - This does not preserve ordering, but is O(1).
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/// - This does not do any bounds checking.
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/// - The element is replaced with the last element in the [`Column`].
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///
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/// # Safety
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/// `row` must be within the range `[0, self.len())`.
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///
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#[inline]
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pub(crate) unsafe fn swap_remove_unchecked(&mut self, row: TableRow) {
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self.data.swap_remove_and_drop_unchecked(row.as_usize());
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self.added_ticks.swap_remove(row.as_usize());
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self.changed_ticks.swap_remove(row.as_usize());
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}
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/// Removes an element from the [`Column`] and returns it and its change detection ticks.
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/// This does not preserve ordering, but is O(1) and does not do any bounds checking.
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///
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/// The element is replaced with the last element in the [`Column`].
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///
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/// It's the caller's responsibility to ensure that the removed value is dropped or used.
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/// Failure to do so may result in resources not being released (i.e. files handles not being
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/// released, memory leaks, etc.)
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///
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/// # Safety
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/// `row` must be within the range `[0, self.len())`.
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#[inline]
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#[must_use = "The returned pointer should be used to dropped the removed component"]
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pub(crate) unsafe fn swap_remove_and_forget_unchecked(
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&mut self,
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row: TableRow,
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) -> (OwningPtr<'_>, ComponentTicks) {
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let data = self.data.swap_remove_and_forget_unchecked(row.as_usize());
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let added = self.added_ticks.swap_remove(row.as_usize()).into_inner();
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let changed = self.changed_ticks.swap_remove(row.as_usize()).into_inner();
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(data, ComponentTicks { added, changed })
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}
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/// Removes the element from `other` at `src_row` and inserts it
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/// into the current column to initialize the values at `dst_row`.
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/// Does not do any bounds checking.
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///
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/// # Safety
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///
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/// - `other` must have the same data layout as `self`
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/// - `src_row` must be in bounds for `other`
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/// - `dst_row` must be in bounds for `self`
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/// - `other[src_row]` must be initialized to a valid value.
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/// - `self[dst_row]` must not be initialized yet.
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#[inline]
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pub(crate) unsafe fn initialize_from_unchecked(
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&mut self,
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other: &mut Column,
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src_row: TableRow,
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dst_row: TableRow,
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) {
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debug_assert!(self.data.layout() == other.data.layout());
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let ptr = self.data.get_unchecked_mut(dst_row.as_usize());
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other.data.swap_remove_unchecked(src_row.as_usize(), ptr);
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*self.added_ticks.get_unchecked_mut(dst_row.as_usize()) =
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other.added_ticks.swap_remove(src_row.as_usize());
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*self.changed_ticks.get_unchecked_mut(dst_row.as_usize()) =
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other.changed_ticks.swap_remove(src_row.as_usize());
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}
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/// Pushes a new value onto the end of the [`Column`].
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///
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/// # Safety
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/// `ptr` must point to valid data of this column's component type
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pub(crate) unsafe fn push(&mut self, ptr: OwningPtr<'_>, ticks: ComponentTicks) {
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self.data.push(ptr);
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self.added_ticks.push(UnsafeCell::new(ticks.added));
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self.changed_ticks.push(UnsafeCell::new(ticks.changed));
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}
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#[inline]
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pub(crate) fn reserve_exact(&mut self, additional: usize) {
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self.data.reserve_exact(additional);
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self.added_ticks.reserve_exact(additional);
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self.changed_ticks.reserve_exact(additional);
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}
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/// Fetches the data pointer to the first element of the [`Column`].
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///
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/// The pointer is type erased, so using this function to fetch anything
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/// other than the first element will require computing the offset using
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/// [`Column::item_layout`].
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#[inline]
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pub fn get_data_ptr(&self) -> Ptr<'_> {
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self.data.get_ptr()
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}
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/// Fetches the slice to the [`Column`]'s data cast to a given type.
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///
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/// Note: The values stored within are [`UnsafeCell`].
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/// Users of this API must ensure that accesses to each individual element
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/// adhere to the safety invariants of [`UnsafeCell`].
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///
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/// # Safety
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/// The type `T` must be the type of the items in this column.
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pub unsafe fn get_data_slice<T>(&self) -> &[UnsafeCell<T>] {
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self.data.get_slice()
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}
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/// Fetches the slice to the [`Column`]'s "added" change detection ticks.
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///
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/// Note: The values stored within are [`UnsafeCell`].
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/// Users of this API must ensure that accesses to each individual element
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/// adhere to the safety invariants of [`UnsafeCell`].
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#[inline]
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pub fn get_added_ticks_slice(&self) -> &[UnsafeCell<Tick>] {
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&self.added_ticks
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}
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/// Fetches the slice to the [`Column`]'s "changed" change detection ticks.
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///
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/// Note: The values stored within are [`UnsafeCell`].
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/// Users of this API must ensure that accesses to each individual element
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/// adhere to the safety invariants of [`UnsafeCell`].
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#[inline]
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pub fn get_changed_ticks_slice(&self) -> &[UnsafeCell<Tick>] {
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&self.changed_ticks
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}
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/// Fetches a reference to the data and change detection ticks at `row`.
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///
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/// Returns `None` if `row` is out of bounds.
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#[inline]
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pub fn get(&self, row: TableRow) -> Option<(Ptr<'_>, TickCells<'_>)> {
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(row.as_usize() < self.data.len())
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// SAFETY: The row is length checked before fetching the pointer. This is being
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// accessed through a read-only reference to the column.
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.then(|| unsafe {
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(
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self.data.get_unchecked(row.as_usize()),
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TickCells {
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added: self.added_ticks.get_unchecked(row.as_usize()),
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changed: self.changed_ticks.get_unchecked(row.as_usize()),
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},
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)
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})
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}
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/// Fetches a read-only reference to the data at `row`.
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///
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/// Returns `None` if `row` is out of bounds.
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#[inline]
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pub fn get_data(&self, row: TableRow) -> Option<Ptr<'_>> {
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(row.as_usize() < self.data.len()).then(|| {
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// SAFETY: The row is length checked before fetching the pointer. This is being
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// accessed through a read-only reference to the column.
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unsafe { self.data.get_unchecked(row.as_usize()) }
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})
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}
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/// Fetches a read-only reference to the data at `row`. Unlike [`Column::get`] this does not
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/// do any bounds checking.
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///
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/// # Safety
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/// - `row` must be within the range `[0, self.len())`.
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/// - no other mutable reference to the data of the same row can exist at the same time
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#[inline]
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pub unsafe fn get_data_unchecked(&self, row: TableRow) -> Ptr<'_> {
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debug_assert!(row.as_usize() < self.data.len());
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self.data.get_unchecked(row.as_usize())
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}
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/// Fetches a mutable reference to the data at `row`.
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///
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/// Returns `None` if `row` is out of bounds.
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#[inline]
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pub fn get_data_mut(&mut self, row: TableRow) -> Option<PtrMut<'_>> {
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(row.as_usize() < self.data.len()).then(|| {
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// SAFETY: The row is length checked before fetching the pointer. This is being
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// accessed through an exclusive reference to the column.
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unsafe { self.data.get_unchecked_mut(row.as_usize()) }
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})
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}
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/// Fetches a mutable reference to the data at `row`. Unlike [`Column::get_data_mut`] this does not
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/// do any bounds checking.
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///
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/// # Safety
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/// - index must be in-bounds
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/// - no other reference to the data of the same row can exist at the same time
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#[inline]
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pub(crate) unsafe fn get_data_unchecked_mut(&mut self, row: TableRow) -> PtrMut<'_> {
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debug_assert!(row.as_usize() < self.data.len());
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self.data.get_unchecked_mut(row.as_usize())
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}
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/// Fetches the "added" change detection tick for the value at `row`.
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///
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/// Returns `None` if `row` is out of bounds.
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///
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/// Note: The values stored within are [`UnsafeCell`].
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/// Users of this API must ensure that accesses to each individual element
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/// adhere to the safety invariants of [`UnsafeCell`].
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#[inline]
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pub fn get_added_tick(&self, row: TableRow) -> Option<&UnsafeCell<Tick>> {
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self.added_ticks.get(row.as_usize())
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}
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/// Fetches the "changed" change detection tick for the value at `row`.
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///
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/// Returns `None` if `row` is out of bounds.
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///
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/// Note: The values stored within are [`UnsafeCell`].
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/// Users of this API must ensure that accesses to each individual element
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/// adhere to the safety invariants of [`UnsafeCell`].
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#[inline]
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pub fn get_changed_tick(&self, row: TableRow) -> Option<&UnsafeCell<Tick>> {
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self.changed_ticks.get(row.as_usize())
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}
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/// Fetches the change detection ticks for the value at `row`.
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///
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/// Returns `None` if `row` is out of bounds.
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#[inline]
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pub fn get_ticks(&self, row: TableRow) -> Option<ComponentTicks> {
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if row.as_usize() < self.data.len() {
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// SAFETY: The size of the column has already been checked.
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Some(unsafe { self.get_ticks_unchecked(row) })
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} else {
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None
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}
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}
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/// Fetches the "added" change detection tick for the value at `row`. Unlike [`Column::get_added_tick`]
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/// this function does not do any bounds checking.
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///
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/// # Safety
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/// `row` must be within the range `[0, self.len())`.
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#[inline]
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pub unsafe fn get_added_tick_unchecked(&self, row: TableRow) -> &UnsafeCell<Tick> {
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debug_assert!(row.as_usize() < self.added_ticks.len());
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self.added_ticks.get_unchecked(row.as_usize())
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}
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|
|
/// Fetches the "changed" change detection tick for the value at `row`. Unlike [`Column::get_changed_tick`]
|
|
/// this function does not do any bounds checking.
|
|
///
|
|
/// # Safety
|
|
/// `row` must be within the range `[0, self.len())`.
|
|
#[inline]
|
|
pub unsafe fn get_changed_tick_unchecked(&self, row: TableRow) -> &UnsafeCell<Tick> {
|
|
debug_assert!(row.as_usize() < self.changed_ticks.len());
|
|
self.changed_ticks.get_unchecked(row.as_usize())
|
|
}
|
|
|
|
/// Fetches the change detection ticks for the value at `row`. Unlike [`Column::get_ticks`]
|
|
/// this function does not do any bounds checking.
|
|
///
|
|
/// # Safety
|
|
/// `row` must be within the range `[0, self.len())`.
|
|
#[inline]
|
|
pub unsafe fn get_ticks_unchecked(&self, row: TableRow) -> ComponentTicks {
|
|
debug_assert!(row.as_usize() < self.added_ticks.len());
|
|
debug_assert!(row.as_usize() < self.changed_ticks.len());
|
|
ComponentTicks {
|
|
added: self.added_ticks.get_unchecked(row.as_usize()).read(),
|
|
changed: self.changed_ticks.get_unchecked(row.as_usize()).read(),
|
|
}
|
|
}
|
|
|
|
/// Clears the column, removing all values.
|
|
///
|
|
/// Note that this function has no effect on the allocated capacity of the [`Column`]>
|
|
pub fn clear(&mut self) {
|
|
self.data.clear();
|
|
self.added_ticks.clear();
|
|
self.changed_ticks.clear();
|
|
}
|
|
|
|
#[inline]
|
|
pub(crate) fn check_change_ticks(&mut self, change_tick: Tick) {
|
|
for component_ticks in &mut self.added_ticks {
|
|
component_ticks.get_mut().check_tick(change_tick);
|
|
}
|
|
for component_ticks in &mut self.changed_ticks {
|
|
component_ticks.get_mut().check_tick(change_tick);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A builder type for constructing [`Table`]s.
|
|
///
|
|
/// - Use [`with_capacity`] to initialize the builder.
|
|
/// - Repeatedly call [`add_column`] to add columns for components.
|
|
/// - Finalize with [`build`] to get the constructed [`Table`].
|
|
///
|
|
/// [`with_capacity`]: Self::with_capacity
|
|
/// [`add_column`]: Self::add_column
|
|
/// [`build`]: Self::build
|
|
pub(crate) struct TableBuilder {
|
|
columns: SparseSet<ComponentId, Column>,
|
|
capacity: usize,
|
|
}
|
|
|
|
impl TableBuilder {
|
|
/// Creates a blank [`Table`], allocating space for `column_capacity` columns
|
|
/// with the capacity to hold `capacity` entities worth of components each.
|
|
pub fn with_capacity(capacity: usize, column_capacity: usize) -> Self {
|
|
Self {
|
|
columns: SparseSet::with_capacity(column_capacity),
|
|
capacity,
|
|
}
|
|
}
|
|
|
|
#[must_use]
|
|
pub fn add_column(mut self, component_info: &ComponentInfo) -> Self {
|
|
self.columns.insert(
|
|
component_info.id(),
|
|
Column::with_capacity(component_info, self.capacity),
|
|
);
|
|
self
|
|
}
|
|
|
|
#[must_use]
|
|
pub fn build(self) -> Table {
|
|
Table {
|
|
columns: self.columns.into_immutable(),
|
|
entities: Vec::with_capacity(self.capacity),
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A column-oriented [structure-of-arrays] based storage for [`Component`]s of entities
|
|
/// in a [`World`].
|
|
///
|
|
/// Conceptually, a `Table` can be thought of as an `HashMap<ComponentId, Column>`, where
|
|
/// each [`Column`] is a type-erased `Vec<T: Component>`. Each row corresponds to a single entity
|
|
/// (i.e. index 3 in Column A and index 3 in Column B point to different components on the same
|
|
/// entity). Fetching components from a table involves fetching the associated column for a
|
|
/// component type (via its [`ComponentId`]), then fetching the entity's row within that column.
|
|
///
|
|
/// [structure-of-arrays]: https://en.wikipedia.org/wiki/AoS_and_SoA#Structure_of_arrays
|
|
/// [`Component`]: crate::component::Component
|
|
/// [`World`]: crate::world::World
|
|
pub struct Table {
|
|
columns: ImmutableSparseSet<ComponentId, Column>,
|
|
entities: Vec<Entity>,
|
|
}
|
|
|
|
impl Table {
|
|
/// Fetches a read-only slice of the entities stored within the [`Table`].
|
|
#[inline]
|
|
pub fn entities(&self) -> &[Entity] {
|
|
&self.entities
|
|
}
|
|
|
|
/// Removes the entity at the given row and returns the entity swapped in to replace it (if an
|
|
/// entity was swapped in)
|
|
///
|
|
/// # Safety
|
|
/// `row` must be in-bounds
|
|
pub(crate) unsafe fn swap_remove_unchecked(&mut self, row: TableRow) -> Option<Entity> {
|
|
for column in self.columns.values_mut() {
|
|
column.swap_remove_unchecked(row);
|
|
}
|
|
let is_last = row.as_usize() == self.entities.len() - 1;
|
|
self.entities.swap_remove(row.as_usize());
|
|
if is_last {
|
|
None
|
|
} else {
|
|
Some(self.entities[row.as_usize()])
|
|
}
|
|
}
|
|
|
|
/// Moves the `row` column values to `new_table`, for the columns shared between both tables.
|
|
/// Returns the index of the new row in `new_table` and the entity in this table swapped in
|
|
/// to replace it (if an entity was swapped in). missing columns will be "forgotten". It is
|
|
/// the caller's responsibility to drop them. Failure to do so may result in resources not
|
|
/// being released (i.e. files handles not being released, memory leaks, etc.)
|
|
///
|
|
/// # Safety
|
|
/// Row must be in-bounds
|
|
pub(crate) unsafe fn move_to_and_forget_missing_unchecked(
|
|
&mut self,
|
|
row: TableRow,
|
|
new_table: &mut Table,
|
|
) -> TableMoveResult {
|
|
debug_assert!(row.as_usize() < self.entity_count());
|
|
let is_last = row.as_usize() == self.entities.len() - 1;
|
|
let new_row = new_table.allocate(self.entities.swap_remove(row.as_usize()));
|
|
for (component_id, column) in self.columns.iter_mut() {
|
|
if let Some(new_column) = new_table.get_column_mut(*component_id) {
|
|
new_column.initialize_from_unchecked(column, row, new_row);
|
|
} else {
|
|
// It's the caller's responsibility to drop these cases.
|
|
let (_, _) = column.swap_remove_and_forget_unchecked(row);
|
|
}
|
|
}
|
|
TableMoveResult {
|
|
new_row,
|
|
swapped_entity: if is_last {
|
|
None
|
|
} else {
|
|
Some(self.entities[row.as_usize()])
|
|
},
|
|
}
|
|
}
|
|
|
|
/// Moves the `row` column values to `new_table`, for the columns shared between both tables.
|
|
/// Returns the index of the new row in `new_table` and the entity in this table swapped in
|
|
/// to replace it (if an entity was swapped in).
|
|
///
|
|
/// # Safety
|
|
/// row must be in-bounds
|
|
pub(crate) unsafe fn move_to_and_drop_missing_unchecked(
|
|
&mut self,
|
|
row: TableRow,
|
|
new_table: &mut Table,
|
|
) -> TableMoveResult {
|
|
debug_assert!(row.as_usize() < self.entity_count());
|
|
let is_last = row.as_usize() == self.entities.len() - 1;
|
|
let new_row = new_table.allocate(self.entities.swap_remove(row.as_usize()));
|
|
for (component_id, column) in self.columns.iter_mut() {
|
|
if let Some(new_column) = new_table.get_column_mut(*component_id) {
|
|
new_column.initialize_from_unchecked(column, row, new_row);
|
|
} else {
|
|
column.swap_remove_unchecked(row);
|
|
}
|
|
}
|
|
TableMoveResult {
|
|
new_row,
|
|
swapped_entity: if is_last {
|
|
None
|
|
} else {
|
|
Some(self.entities[row.as_usize()])
|
|
},
|
|
}
|
|
}
|
|
|
|
/// Moves the `row` column values to `new_table`, for the columns shared between both tables.
|
|
/// Returns the index of the new row in `new_table` and the entity in this table swapped in
|
|
/// to replace it (if an entity was swapped in).
|
|
///
|
|
/// # Safety
|
|
/// `row` must be in-bounds. `new_table` must contain every component this table has
|
|
pub(crate) unsafe fn move_to_superset_unchecked(
|
|
&mut self,
|
|
row: TableRow,
|
|
new_table: &mut Table,
|
|
) -> TableMoveResult {
|
|
debug_assert!(row.as_usize() < self.entity_count());
|
|
let is_last = row.as_usize() == self.entities.len() - 1;
|
|
let new_row = new_table.allocate(self.entities.swap_remove(row.as_usize()));
|
|
for (component_id, column) in self.columns.iter_mut() {
|
|
new_table
|
|
.get_column_mut(*component_id)
|
|
.debug_checked_unwrap()
|
|
.initialize_from_unchecked(column, row, new_row);
|
|
}
|
|
TableMoveResult {
|
|
new_row,
|
|
swapped_entity: if is_last {
|
|
None
|
|
} else {
|
|
Some(self.entities[row.as_usize()])
|
|
},
|
|
}
|
|
}
|
|
|
|
/// Fetches a read-only reference to the [`Column`] for a given [`Component`] within the
|
|
/// table.
|
|
///
|
|
/// Returns `None` if the corresponding component does not belong to the table.
|
|
///
|
|
/// [`Component`]: crate::component::Component
|
|
#[inline]
|
|
pub fn get_column(&self, component_id: ComponentId) -> Option<&Column> {
|
|
self.columns.get(component_id)
|
|
}
|
|
|
|
/// Fetches a mutable reference to the [`Column`] for a given [`Component`] within the
|
|
/// table.
|
|
///
|
|
/// Returns `None` if the corresponding component does not belong to the table.
|
|
///
|
|
/// [`Component`]: crate::component::Component
|
|
#[inline]
|
|
pub(crate) fn get_column_mut(&mut self, component_id: ComponentId) -> Option<&mut Column> {
|
|
self.columns.get_mut(component_id)
|
|
}
|
|
|
|
/// Checks if the table contains a [`Column`] for a given [`Component`].
|
|
///
|
|
/// Returns `true` if the column is present, `false` otherwise.
|
|
///
|
|
/// [`Component`]: crate::component::Component
|
|
#[inline]
|
|
pub fn has_column(&self, component_id: ComponentId) -> bool {
|
|
self.columns.contains(component_id)
|
|
}
|
|
|
|
/// Reserves `additional` elements worth of capacity within the table.
|
|
pub(crate) fn reserve(&mut self, additional: usize) {
|
|
if self.entities.capacity() - self.entities.len() < additional {
|
|
self.entities.reserve(additional);
|
|
|
|
// use entities vector capacity as driving capacity for all related allocations
|
|
let new_capacity = self.entities.capacity();
|
|
|
|
for column in self.columns.values_mut() {
|
|
column.reserve_exact(new_capacity - column.len());
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Allocates space for a new entity
|
|
///
|
|
/// # Safety
|
|
/// the allocated row must be written to immediately with valid values in each column
|
|
pub(crate) unsafe fn allocate(&mut self, entity: Entity) -> TableRow {
|
|
self.reserve(1);
|
|
let index = self.entities.len();
|
|
self.entities.push(entity);
|
|
for column in self.columns.values_mut() {
|
|
column.data.set_len(self.entities.len());
|
|
column.added_ticks.push(UnsafeCell::new(Tick::new(0)));
|
|
column.changed_ticks.push(UnsafeCell::new(Tick::new(0)));
|
|
}
|
|
TableRow::from_usize(index)
|
|
}
|
|
|
|
/// Gets the number of entities currently being stored in the table.
|
|
#[inline]
|
|
pub fn entity_count(&self) -> usize {
|
|
self.entities.len()
|
|
}
|
|
|
|
/// Gets the number of components being stored in the table.
|
|
#[inline]
|
|
pub fn component_count(&self) -> usize {
|
|
self.columns.len()
|
|
}
|
|
|
|
/// Gets the maximum number of entities the table can currently store
|
|
/// without reallocating the underlying memory.
|
|
#[inline]
|
|
pub fn entity_capacity(&self) -> usize {
|
|
self.entities.capacity()
|
|
}
|
|
|
|
/// Checks if the [`Table`] is empty or not.
|
|
///
|
|
/// Returns `true` if the table contains no entities, `false` otherwise.
|
|
#[inline]
|
|
pub fn is_empty(&self) -> bool {
|
|
self.entities.is_empty()
|
|
}
|
|
|
|
pub(crate) fn check_change_ticks(&mut self, change_tick: Tick) {
|
|
for column in self.columns.values_mut() {
|
|
column.check_change_ticks(change_tick);
|
|
}
|
|
}
|
|
|
|
/// Iterates over the [`Column`]s of the [`Table`].
|
|
pub fn iter(&self) -> impl Iterator<Item = &Column> {
|
|
self.columns.values()
|
|
}
|
|
|
|
/// Clears all of the stored components in the [`Table`].
|
|
pub(crate) fn clear(&mut self) {
|
|
self.entities.clear();
|
|
for column in self.columns.values_mut() {
|
|
column.clear();
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A collection of [`Table`] storages, indexed by [`TableId`]
|
|
///
|
|
/// Can be accessed via [`Storages`](crate::storage::Storages)
|
|
pub struct Tables {
|
|
tables: Vec<Table>,
|
|
table_ids: HashMap<Box<[ComponentId]>, TableId>,
|
|
}
|
|
|
|
impl Default for Tables {
|
|
fn default() -> Self {
|
|
let empty_table = TableBuilder::with_capacity(0, 0).build();
|
|
Tables {
|
|
tables: vec![empty_table],
|
|
table_ids: HashMap::default(),
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(crate) struct TableMoveResult {
|
|
pub swapped_entity: Option<Entity>,
|
|
pub new_row: TableRow,
|
|
}
|
|
|
|
impl Tables {
|
|
/// Returns the number of [`Table`]s this collection contains
|
|
#[inline]
|
|
pub fn len(&self) -> usize {
|
|
self.tables.len()
|
|
}
|
|
|
|
/// Returns true if this collection contains no [`Table`]s
|
|
#[inline]
|
|
pub fn is_empty(&self) -> bool {
|
|
self.tables.is_empty()
|
|
}
|
|
|
|
/// Fetches a [`Table`] by its [`TableId`].
|
|
///
|
|
/// Returns `None` if `id` is invalid.
|
|
#[inline]
|
|
pub fn get(&self, id: TableId) -> Option<&Table> {
|
|
self.tables.get(id.as_usize())
|
|
}
|
|
|
|
/// Fetches mutable references to two different [`Table`]s.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if `a` and `b` are equal.
|
|
#[inline]
|
|
pub(crate) fn get_2_mut(&mut self, a: TableId, b: TableId) -> (&mut Table, &mut Table) {
|
|
if a.as_usize() > b.as_usize() {
|
|
let (b_slice, a_slice) = self.tables.split_at_mut(a.as_usize());
|
|
(&mut a_slice[0], &mut b_slice[b.as_usize()])
|
|
} else {
|
|
let (a_slice, b_slice) = self.tables.split_at_mut(b.as_usize());
|
|
(&mut a_slice[a.as_usize()], &mut b_slice[0])
|
|
}
|
|
}
|
|
|
|
/// Attempts to fetch a table based on the provided components,
|
|
/// creating and returning a new [`Table`] if one did not already exist.
|
|
///
|
|
/// # Safety
|
|
/// `component_ids` must contain components that exist in `components`
|
|
pub(crate) unsafe fn get_id_or_insert(
|
|
&mut self,
|
|
component_ids: &[ComponentId],
|
|
components: &Components,
|
|
) -> TableId {
|
|
let tables = &mut self.tables;
|
|
let (_key, value) = self
|
|
.table_ids
|
|
.raw_entry_mut()
|
|
.from_key(component_ids)
|
|
.or_insert_with(|| {
|
|
let mut table = TableBuilder::with_capacity(0, component_ids.len());
|
|
for component_id in component_ids {
|
|
table = table.add_column(components.get_info_unchecked(*component_id));
|
|
}
|
|
tables.push(table.build());
|
|
(component_ids.into(), TableId::from_usize(tables.len() - 1))
|
|
});
|
|
|
|
*value
|
|
}
|
|
|
|
/// Iterates through all of the tables stored within in [`TableId`] order.
|
|
pub fn iter(&self) -> std::slice::Iter<'_, Table> {
|
|
self.tables.iter()
|
|
}
|
|
|
|
/// Clears all data from all [`Table`]s stored within.
|
|
pub(crate) fn clear(&mut self) {
|
|
for table in &mut self.tables {
|
|
table.clear();
|
|
}
|
|
}
|
|
|
|
pub(crate) fn check_change_ticks(&mut self, change_tick: Tick) {
|
|
for table in &mut self.tables {
|
|
table.check_change_ticks(change_tick);
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Index<TableId> for Tables {
|
|
type Output = Table;
|
|
|
|
#[inline]
|
|
fn index(&self, index: TableId) -> &Self::Output {
|
|
&self.tables[index.as_usize()]
|
|
}
|
|
}
|
|
|
|
impl IndexMut<TableId> for Tables {
|
|
#[inline]
|
|
fn index_mut(&mut self, index: TableId) -> &mut Self::Output {
|
|
&mut self.tables[index.as_usize()]
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use crate as bevy_ecs;
|
|
use crate::component::Component;
|
|
use crate::ptr::OwningPtr;
|
|
use crate::storage::Storages;
|
|
use crate::{
|
|
component::{Components, Tick},
|
|
entity::Entity,
|
|
storage::{TableBuilder, TableRow},
|
|
};
|
|
#[derive(Component)]
|
|
struct W<T>(T);
|
|
|
|
#[test]
|
|
fn table() {
|
|
let mut components = Components::default();
|
|
let mut storages = Storages::default();
|
|
let component_id = components.init_component::<W<TableRow>>(&mut storages);
|
|
let columns = &[component_id];
|
|
let mut table = TableBuilder::with_capacity(0, columns.len())
|
|
.add_column(components.get_info(component_id).unwrap())
|
|
.build();
|
|
let entities = (0..200).map(Entity::from_raw).collect::<Vec<_>>();
|
|
for entity in &entities {
|
|
// SAFETY: we allocate and immediately set data afterwards
|
|
unsafe {
|
|
let row = table.allocate(*entity);
|
|
let value: W<TableRow> = W(row);
|
|
OwningPtr::make(value, |value_ptr| {
|
|
table.get_column_mut(component_id).unwrap().initialize(
|
|
row,
|
|
value_ptr,
|
|
Tick::new(0),
|
|
);
|
|
});
|
|
};
|
|
}
|
|
|
|
assert_eq!(table.entity_capacity(), 256);
|
|
assert_eq!(table.entity_count(), 200);
|
|
}
|
|
}
|