Commit graph

85 commits

Author SHA1 Message Date
Joshua Chapman
9dd8fbc570 Added Ref to allow immutable access with change detection (#7097)
# Objective

- Fixes #7066 

## Solution

- Split the ChangeDetection trait into ChangeDetection and ChangeDetectionMut
- Added Ref as equivalent to &T with change detection

---

## Changelog

- Support for Ref which allow inspecting change detection flags in an immutable way

## Migration Guide

- While bevy prelude includes both ChangeDetection and ChangeDetectionMut any code explicitly referencing ChangeDetection might need to be updated to ChangeDetectionMut or both. Specifically any reading logic requires ChangeDetection while writes requires ChangeDetectionMut.

use bevy_ecs::change_detection::DetectChanges -> use bevy_ecs::change_detection::{DetectChanges, DetectChangesMut}

- Previously Res had methods to access change detection `is_changed` and `is_added` those methods have been moved to the `DetectChanges` trait. If you are including bevy prelude you will have access to these types otherwise you will need to `use bevy_ecs::change_detection::DetectChanges` to continue using them.
2023-01-11 15:41:54 +00:00
James Liu
aaf384ae58 Panic on dropping NonSend in non-origin thread. (#6534)
# Objective

Fixes #3310. Fixes #6282. Fixes #6278. Fixes #3666.

## Solution
Split out `!Send` resources into `NonSendResources`. Add a `origin_thread_id` to all `!Send` Resources, check it on dropping `NonSendResourceData`, if there's a mismatch, panic. Moved all of the checks that `MainThreadValidator` would do into `NonSendResources` instead.

All `!Send` resources now individually track which thread they were inserted from. This is validated against for every access, mutation, and drop that could be done against the value. 

A regression test using an altered version of the example from #3310 has been added.

This is a stopgap solution for the current status quo. A full solution may involve fully removing `!Send` resources/components from `World`, which will likely require a much more thorough design on how to handle the existing in-engine and ecosystem use cases.

This PR also introduces another breaking change:

```rust
    use bevy_ecs::prelude::*;

    #[derive(Resource)]
    struct Resource(u32);

    fn main() {
        let mut world = World::new();
        world.insert_resource(Resource(1));
        world.insert_non_send_resource(Resource(2));
        let res = world.get_resource_mut::<Resource>().unwrap();
        assert_eq!(res.0, 2);
    }
```

This code will run correctly on 0.9.1 but not with this PR, since NonSend resources and normal resources have become actual distinct concepts storage wise.

## Changelog
Changed: Fix soundness bug with `World: Send`. Dropping a `World` that contains a `!Send` resource on the wrong thread will now panic.

## Migration Guide
Normal resources and `NonSend` resources no longer share the same backing storage. If `R: Resource`, then `NonSend<R>` and `Res<R>` will return different instances from each other. If you are using both `Res<T>` and `NonSend<T>` (or their mutable variants), to fetch the same resources, it's strongly advised to use `Res<T>`.
2023-01-09 20:40:34 +00:00
James Liu
a5b1c46d5b Extend EntityLocation with TableId and TableRow (#6681)
# Objective
`Query::get` and other random access methods require looking up `EntityLocation` for every provided entity, then always looking up the `Archetype` to get the table ID and table row. This requires 4 total random fetches from memory: the `Entities` lookup, the `Archetype` lookup, the table row lookup, and the final fetch from table/sparse sets. If `EntityLocation` contains the table ID and table row, only the `Entities` lookup and the final storage fetch are required.

## Solution
Add `TableId` and table row to `EntityLocation`. Ensure it's updated whenever entities are moved around. To ensure `EntityMeta` does not grow bigger, both `TableId` and `ArchetypeId` have been shrunk to u32, and the archetype index and table row are stored as u32s instead of as usizes. This should shrink `EntityMeta` by 4 bytes, from 24 to 20 bytes, as there is no padding anymore due to the change in alignment.

This idea was partially concocted by @BoxyUwU. 

## Performance
This should restore the `Query::get` "gains" lost to #6625 that were introduced in #4800 without being unsound, and also incorporates some of the memory usage reductions seen in #3678.

This also removes the same lookups during add/remove/spawn commands, so there may be a bit of a speedup in commands and `Entity{Ref,Mut}`.

---

## Changelog
Added: `EntityLocation::table_id`
Added: `EntityLocation::table_row`.
Changed: `World`s can now only hold a maximum of 2<sup>32</sup>- 1 archetypes.
Changed: `World`s can now only hold a maximum of 2<sup>32</sup> - 1 tables.

## Migration Guide

A `World` can only hold a maximum of 2<sup>32</sup> - 1 archetypes and tables now. If your use case requires more than this, please file an issue explaining your use case.
2023-01-02 21:25:04 +00:00
ira
0761594dd8 Use World helper methods for sending HierarchyEvents (#6921)
A code-quality PR

Also cleans up the helper methods by just importing the `Event` type

Co-authored-by: devil-ira <justthecooldude@gmail.com>
2022-12-20 16:17:07 +00:00
Jerome Humbert
07e7fa5a4d Document World::clear_trackers() (#6520)
# Objective

Document `World::clear_trackers()`.

## Solution

Document the `World::clear_trackers()` method, and briefly how it's related to change detection and `RemovedComponents`.

This is a follow-up from [this discussion](https://discord.com/channels/691052431525675048/749335865876021248/1039628807025479700) on Discord.
2022-12-11 18:10:01 +00:00
James Liu
530be10e72 Newtype ArchetypeRow and TableRow (#4878)
# Objective
Prevent future unsoundness that was seen in #6623.

## Solution
Newtype both indexes in `Archetype` and `Table` as `ArchetypeRow` and `TableRow`. This avoids weird numerical manipulation on the indices, and can be stored and treated opaquely. Also enforces the source and destination of where these indices at a type level.

---

## Changelog
Changed: `Archetype` indices and `Table` rows have been newtyped as `ArchetypeRow` and `TableRow`.
2022-12-06 01:38:21 +00:00
James Liu
a3f203b504 Use T::Storage::STORAGE_TYPE to optimize out unused branches (#6800)
# Objective
`EntityRef::get` and friends all type erase calls to fetch the target components by using passing in the `TypeId` instead of using generics. This is forcing a lookup to `Components` to fetch the storage type. This adds an extra memory lookup and forces a runtime branch instead of allowing the compiler to optimize out the unused branch.

## Solution
Leverage `Component::Storage::STORAGE_TYPE` as a constant instead of fetching the metadata from `Components`.

## Performance
This has a near 2x speedup for all calls to `World::get`. Microbenchmark results from my local machine. `Query::get_component`, which uses `EntityRef::get` internally also show a slight speed up. This has closed the gap between `World::get` and `Query::get` for the same use case.

```
group                                                             entity-ref-generics                     main
-----                                                             -------------------                     ----
query_get_component/50000_entities_sparse                         1.00   890.6±40.42µs        ? ?/sec     1.10   980.6±28.22µs        ? ?/sec
query_get_component/50000_entities_table                          1.00   968.5±73.73µs        ? ?/sec     1.08  1048.8±31.76µs        ? ?/sec
query_get_component_simple/system                                 1.00    703.2±4.37µs        ? ?/sec     1.00    702.1±6.13µs        ? ?/sec
query_get_component_simple/unchecked                              1.02    855.8±8.98µs        ? ?/sec     1.00    843.1±8.19µs        ? ?/sec
world_get/50000_entities_sparse                                   1.00    202.3±3.15µs        ? ?/sec     1.85   374.0±20.96µs        ? ?/sec
world_get/50000_entities_table                                    1.00    193.0±1.78µs        ? ?/sec     2.02   389.2±26.55µs        ? ?/sec
world_query_get/50000_entities_sparse                             1.01    162.4±2.23µs        ? ?/sec     1.00    161.3±0.95µs        ? ?/sec
world_query_get/50000_entities_table                              1.00    199.9±0.63µs        ? ?/sec     1.00    200.2±0.74µs        ? ?/sec
```

This should also, by proxy, speed up the `ReflectComponent` APIs as most of those use `World::get` variants internally.
2022-12-05 23:56:33 +00:00
JoJoJet
83e8224694 Add missing docs to World::change_tick and World::read_change_tick (#6765)
# Objective

The methods `World::change_tick` and `World::read_change_tick` lack documentation and have confusingly similar behavior.

## Solution

Add documentation and clarify the distinction between the two functions.
2022-12-05 23:23:14 +00:00
Martín Maita
eff632dac8 Replace World::read_change_ticks with World::change_ticks within bevy_ecs crate (#6816)
# Objective

- Fixes #6812.

## Solution

- Replaced `World::read_change_ticks` with `World::change_ticks` within `bevy_ecs` crate in places where `World` references were mutable.

---
2022-12-05 22:49:05 +00:00
James Liu
e8c0df9e1e Allow iterating over with EntityRef over the entire World (#6843)
# Objective
Partially addresses #5504. Allow users to get an `Iterator<Item = EntityRef<'a>>` over all entities in the `World`.

## Solution
Change `World::iter_entities` to return an iterator of `EntityRef` instead of `Entity`.

Not sure how to tackle making an `Iterator<Item = EntityMut<'_>>` without being horribly unsound. Might need to wait for `LendingIterator` to stabilize so we can ensure only one of them is valid at a given time.

---

## Changelog
Changed: `World::iter_entities` now returns an iterator of `EntityRef` instead of `Entity`.
2022-12-05 22:35:02 +00:00
James Liu
e954b8573c Lock down access to Entities (#6740)
# Objective
The soundness of the ECS `World` partially relies on the correctness of the state of `Entities` stored within it. We're currently allowing users to (unsafely) mutate it, as well as readily construct it without using a `World`. While this is not strictly unsound so long as users (including `bevy_render`) safely use the APIs, it's a fairly easy path to unsoundness without much of a guard rail.

Addresses #3362 for `bevy_ecs::entity`. Incorporates the changes from #3985.

## Solution
Remove `Entities`'s  `Default` implementation and force access to the type to only be through a properly constructed `World`.

Additional cleanup for other parts of `bevy_ecs::entity`:

 - `Entity::index` and `Entity::generation` are no longer `pub(crate)`, opting to force the rest of bevy_ecs to use the public interface to access these values.
 - `EntityMeta` is no longer `pub` and also not `pub(crate)` to attempt to cut down on updating `generation` without going through an `Entities` API. It's currently inaccessible except via the `pub(crate)` Vec on `Entities`, there was no way for an outside user to use it.
 - Added `Entities::set`, an unsafe `pub(crate)` API for setting the location of an Entity (parallel to `Entities::get`) that replaces the internal case where we need to set the location of an entity when it's been spawned, moved, or despawned.
 - `Entities::alloc_at_without_replacement` is only used in `World::get_or_spawn` within the first party crates, and I cannot find a public use of this API in any ecosystem crate that I've checked (via GitHub search).
 - Attempted to document the few remaining undocumented public APIs in the module.

---

## Changelog
Removed: `Entities`'s `Default` implementation.
Removed: `EntityMeta`
Removed: `Entities::alloc_at_without_replacement` and `AllocAtWithoutReplacement`.

Co-authored-by: james7132 <contact@jamessliu.com>
Co-authored-by: James Liu <contact@jamessliu.com>
2022-11-28 20:39:02 +00:00
James Liu
d79888bdae Document and lock down types in bevy_ecs::archetype (#6742)
# Objective
Document `bevy_ecs::archetype` and and declutter the public documentation for the module by making types non-`pub`.

Addresses #3362 for `bevy_ecs::archetype`.

## Solution
 - Add module level documentation.
 - Add type and API level documentation for all public facing types.
 - Make `ArchetypeId`, `ArchetypeGeneration`, and `ArchetypeComponentId` truly opaque IDs that are not publicly constructable. 
 - Make `AddBundle` non-pub, make `Edges::get_add_bundle` return a `Option<ArchetypeId>` and fork the existing function into `Edges::get_add_bundle_internal`.
 - Remove `pub(crate)` on fields that have a corresponding pub accessor function.
 - Removed the `Archetypes: Default` impl, opting for a `pub(crate) fn new` alternative instead.

---

## Changelog
Added: `ArchetypeGeneration` now implements `Ord` and `PartialOrd`.
Removed: `Archetypes`'s `Default` implementation.
Removed: `Archetype::new` and `Archetype::is_empty`.
Removed: `ArchetypeId::new` and `ArchetypeId::value`.
Removed: `ArchetypeGeneration::value`
Removed: `ArchetypeIdentity`.
Removed: `ArchetypeComponentId::new` and `ArchetypeComponentId::value`.
Removed: `AddBundle`. `Edges::get_add_bundle` now returns `Option<ArchetypeId>`
2022-11-28 13:54:12 +00:00
JoJoJet
1615834536 Fix an incorrect safety comment in World::get_resource (#6764)
# Objective

* Fix #6307

## Solution

* Rewrite the safety comment to reflect the actual invariants being asserted.
2022-11-28 13:40:26 +00:00
James Liu
55ca7fc88e Split Component Ticks (#6547)
# Objective
Fixes #4884. `ComponentTicks` stores both added and changed ticks contiguously in the same 8 bytes. This is convenient when passing around both together, but causes half the bytes fetched from memory for the purposes of change detection to effectively go unused. This is inefficient when most queries (no filter, mutating *something*) only write out to the changed ticks.

## Solution
Split the storage for change detection ticks into two separate `Vec`s inside `Column`. Fetch only what is needed during iteration.

This also potentially also removes one blocker from autovectorization of dense queries.

EDIT: This is confirmed to enable autovectorization of dense queries in `for_each` and `par_for_each`  where possible.  Unfortunately `iter` has other blockers that prevent it.

### TODO

 - [x] Microbenchmark
 - [x] Check if this allows query iteration to autovectorize simple loops.
 - [x] Clean up all of the spurious tuples now littered throughout the API

### Open Questions

 - ~~Is `Mut::is_added` absolutely necessary? Can we not just use `Added` or `ChangeTrackers`?~~ It's optimized out if unused.
 - ~~Does the fetch of the added ticks get optimized out if not used?~~ Yes it is.

---

## Changelog
Added: `Tick`, a wrapper around a single change detection tick.
Added: `Column::get_added_ticks`
Added: `Column::get_column_ticks`
Added: `SparseSet::get_added_ticks`
Added: `SparseSet::get_column_ticks`
Changed: `Column` now stores added and changed ticks separately internally.
Changed: Most APIs returning `&UnsafeCell<ComponentTicks>` now returns `TickCells` instead, which contains two separate `&UnsafeCell<Tick>` for either component ticks.
Changed: `Query::for_each(_mut)`, `Query::par_for_each(_mut)` will now leverage autovectorization to speed up query iteration where possible.

## Migration Guide
TODO
2022-11-21 12:59:09 +00:00
ira
944b311c67 Improve logging consistency for entity despawning (#6501)
* Move the despawn debug log from `World::despawn` to `EntityMut::despawn`.
 * Move the despawn non-existent warning log from `Commands::despawn` to `World::despawn`.

This should make logging consistent regardless of which of the three `despawn` methods is used.

Co-authored-by: devil-ira <justthecooldude@gmail.com>
2022-11-07 19:23:34 +00:00
Carter Anderson
2e653e5774 Fix spawning empty bundles (#6425)
# Objective

Alternative to #6424 
Fixes #6226

Fixes spawning empty bundles

## Solution

Add `BundleComponentStatus` trait and implement it for `AddBundle` and a new `SpawnBundleStatus` type (which always returns an Added status). `write_components` is now generic on `BundleComponentStatus` instead of taking `AddBundle` directly. This means BundleSpawner can now avoid needing AddBundle from the Empty archetype, which means BundleSpawner no longer needs a reference to the original archetype.

In theory this cuts down on the work done in `write_components` when spawning, but I'm seeing no change in the spawn benchmarks.
2022-11-03 22:50:41 +00:00
Edvin Kjell
a8a62fcf3d [Fixes #6059] `Entity`'s “ID” should be named “index” instead (#6107)
# Objective

Fixes #6059, changing all incorrect occurrences of ``id`` in the ``entity`` module to ``index``:

* struct level documentation,
* ``id`` struct field,
* ``id`` method and its documentation.

## Solution

Renaming and verifying using CI. 


Co-authored-by: Edvin Kjell <43633999+Edwox@users.noreply.github.com>
2022-11-02 15:19:50 +00:00
Jakob Hellermann
e71c4d2802 fix nightly clippy warnings (#6395)
# Objective

- fix new clippy lints before they get stable and break CI

## Solution

- run `clippy --fix` to auto-fix machine-applicable lints
- silence `clippy::should_implement_trait` for `fn HandleId::default<T: Asset>`

## Changes
- always prefer `format!("{inline}")` over `format!("{}", not_inline)`
- prefer `Box::default` (or `Box::<T>::default` if necessary) over `Box::new(T::default())`
2022-10-28 21:03:01 +00:00
James Liu
fe7ebd4326 Clean up Fetch code (#4800)
# Objective
Clean up code surrounding fetch by pulling out the common parts into the iteration code.

## Solution
Merge `Fetch::table_fetch` and `Fetch::archetype_fetch` into a single API: `Fetch::fetch(&mut self, entity: &Entity, table_row: &usize)`. This provides everything any fetch requires to internally decide which storage to read from and get the underlying data. All of these functions are marked as `#[inline(always)]` and the arguments are passed as references to attempt to optimize out the argument that isn't being used.

External to `Fetch`, Query iteration has been changed to keep track of the table row and entity outside of fetch, which moves a lot of the expensive bookkeeping `Fetch` structs had previously done internally into the outer loop.

~~TODO: Benchmark, docs~~ Done.

---

## Changelog
Changed: `Fetch::table_fetch` and `Fetch::archetype_fetch` have been merged into a single `Fetch::fetch` function.

## Migration Guide
TODO

Co-authored-by: Brian Merchant <bhmerchang@gmail.com>
Co-authored-by: Saverio Miroddi <saverio.pub2@gmail.com>
2022-10-28 09:25:50 +00:00
Lena Milizé
b2f223b98f document insert_non_send_resource panics (#6328)
Signed-off-by: Lena Milizé <me@lvmn.org>

# Objective

Fixes #6277.

## Solution

Adds `# Panics` section to [`fn insert_non_send_resource`](http://dev-docs.bevyengine.org/bevy/ecs/world/struct.World.html#method.insert_non_send_resource) documentation, which explains that it panics when called from thread other than main thread.
2022-10-24 14:53:16 +00:00
James Liu
2b96530947 Extract Resources into their own dedicated storage (#4809)
# Objective
At least partially addresses #6282.

Resources are currently stored as a dedicated Resource archetype (ID 1). This allows for easy code reusability, but unnecessarily adds 72 bytes (on 64-bit systems) to the struct that is only used for that one archetype. It also requires several fields to be `pub(crate)` which isn't ideal.

This should also remove one sparse-set lookup from fetching, inserting, and removing resources from a `World`.

## Solution

- Add `Resources` parallel to `Tables` and `SparseSets` and extract the functionality used by `Archetype` in it.
- Remove `unique_components` from `Archetype`
- Remove the `pub(crate)` on `Archetype::components`.
- Remove `ArchetypeId::RESOURCE`
- Remove `Archetypes::resource` and `Archetypes::resource_mut`

---

## Changelog
Added: `Resources` type to store resources.
Added: `Storages::resource`
Removed: `ArchetypeId::RESOURCE`
Removed: `Archetypes::resource` and `Archetypes::resources`
Removed: `Archetype::unique_components` and `Archetypes::unique_components_mut`

## Migration Guide
Resources have been moved to `Resources` under `Storages` in `World`. All code dependent on `Archetype::unique_components(_mut)` should access it via `world.storages().resources()` instead.

All APIs accessing the raw data of individual resources (mutable *and* read-only) have been removed as these APIs allowed for unsound unsafe code. All usages of these APIs should be changed to use `World::{get, insert, remove}_resource`.
2022-10-24 13:46:36 +00:00
mike
a0f1468108 Add iter_entities to World #6228 (#6242)
# Objective

- Add a way to iterate over all entities from &World

## Solution

- Added a function `iter_entities` on World which returns an iterator of `Entity` derived from the entities in the `World`'s `archetypes`

---

## Changelog

- Added a function `iter_entities` on World, allowing iterating over all entities in contexts where you only have read-only access to the World.
2022-10-17 13:47:00 +00:00
Dawid Piotrowski
0bf7f3153d Allow access to non-send resource through World::resource_scope (#6113)
# Objective

Relaxes the trait bound for `World::resource_scope` to allow non-send resources. Fixes #6037.

## Solution

No big changes in code had to be made. Added a check so that the non-send resources won't be accessed from a different thread.

---

## Changelog
 - `World::resource_scope` accepts non-send resources now
 - `World::resource_scope` verifies non-send access if the resource is non-send
 - Two new tests are added, one for valid use of `World::resource_scope` with a non-send resource, and one for invalid use (calling it from a different thread, resulting in panic)

Co-authored-by: Dawid Piotrowski <41804418+Pietrek14@users.noreply.github.com>
2022-09-28 17:53:58 +00:00
Carter Anderson
01aedc8431 Spawn now takes a Bundle (#6054)
# Objective

Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands).

## Solution

All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input:

```rust
// before:
commands
  .spawn()
  .insert((A, B, C));
world
  .spawn()
  .insert((A, B, C);

// after
commands.spawn((A, B, C));
world.spawn((A, B, C));
```

All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api.  

By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`).

This improves spawn performance by over 10%:
![image](https://user-images.githubusercontent.com/2694663/191627587-4ab2f949-4ccd-4231-80eb-80dd4d9ad6b9.png)

To take this measurement, I added a new `world_spawn` benchmark.

Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main.

**Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).** 

---

## Changelog

- All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input
- All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api
- World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior.  

## Migration Guide

```rust
// Old (0.8):
commands
  .spawn()
  .insert_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));

// Old (0.8):
commands.spawn_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));

// Old (0.8):
let entity = commands.spawn().id();
// New (0.9)
let entity = commands.spawn_empty().id();

// Old (0.8)
let entity = world.spawn().id();
// New (0.9)
let entity = world.spawn_empty();
```
2022-09-23 19:55:54 +00:00
Carter Anderson
cd15f0f5be Accept Bundles for insert and remove. Deprecate insert/remove_bundle (#6039)
# Objective

Take advantage of the "impl Bundle for Component" changes in #2975 / add the follow up changes discussed there.

## Solution

- Change `insert` and `remove` to accept a Bundle instead of a Component (for both Commands and World)
- Deprecate `insert_bundle`, `remove_bundle`, and `remove_bundle_intersection`
- Add `remove_intersection`

---

## Changelog

- Change `insert` and `remove` now accept a Bundle instead of a Component (for both Commands and World)
- `insert_bundle` and `remove_bundle` are deprecated
 

## Migration Guide

Replace `insert_bundle` with `insert`:
```rust
// Old (0.8)
commands.spawn().insert_bundle(SomeBundle::default());
// New (0.9)
commands.spawn().insert(SomeBundle::default());
```

Replace `remove_bundle` with `remove`:
```rust
// Old (0.8)
commands.entity(some_entity).remove_bundle::<SomeBundle>();
// New (0.9)
commands.entity(some_entity).remove::<SomeBundle>();
```

Replace `remove_bundle_intersection` with `remove_intersection`:
```rust
// Old (0.8)
world.entity_mut(some_entity).remove_bundle_intersection::<SomeBundle>();
// New (0.9)
world.entity_mut(some_entity).remove_intersection::<SomeBundle>();
```

Consider consolidating as many operations as possible to improve ergonomics and cut down on archetype moves:
```rust
// Old (0.8)
commands.spawn()
  .insert_bundle(SomeBundle::default())
  .insert(SomeComponent);

// New (0.9) - Option 1
commands.spawn().insert((
  SomeBundle::default(),
  SomeComponent,
))

// New (0.9) - Option 2
commands.spawn_bundle((
  SomeBundle::default(),
  SomeComponent,
))
```

## Next Steps

Consider changing `spawn` to accept a bundle and deprecate `spawn_bundle`.
2022-09-21 21:47:53 +00:00
targrub
d0e294c86b Query filter types must be ReadOnlyWorldQuery (#6008)
# Objective

Fixes Issue #6005.

## Solution

Replaced WorldQuery with ReadOnlyWorldQuery on F generic in Query filters and QueryState to restrict its trait bound.

## Migration Guide

Query filter (`F`) generics are now bound by `ReadOnlyWorldQuery`, rather than `WorldQuery`. If for some reason you were requesting `Query<&A, &mut B>`, please use `Query<&A, With<B>>` instead.
2022-09-18 23:52:01 +00:00
Boxy
df31b7d762 Remove insert_resource_with_id (#5608)
# Objective

remove `insert_resource_with_id` because `insert_resource_by_id` exists and does almost exactly the same thing

blocked on #5587 because otherwise we will leak a resource when it's inserted 

## Solution

remove the function and also add a safety invariant of to `insert_resource_by_id` that the id be valid for the world.

I didn't see any discussion in #4447 about this safety invariant being left off in favor of a panic so I'm curious if there was one or if it just seemed nicer to have less safety invariants for callers to uphold 😅 

---

## Changelog

- safety invariant added to `insert_resource_by_id` requiring the id to be valid for world

## Migration Guide

- audit any calls to `insert_resource_by_id` making sure that the id is valid for the world

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-08-30 20:32:15 +00:00
Nathan Ward
00323b3048 Better error message for World::resource_scope (#5727)
# Objective

- Fixes #5365 
- The `assert!()` when the resource from `World::resource_scope` is inserted into the world is not descriptive.

## Solution

- Add more context to the assert inside of `World::resource_scope` when the `FnOnce` param inserts the resource.
2022-08-18 18:53:08 +00:00
Jakob Hellermann
5595733035 drop old value in insert_resource_by_id if exists (#5587)
# Objective

While trying out the lint `unsafe_op_in_unsafe_fn` I noticed that `insert_resource_by_id` didn't drop the old value if it already existed, and reimplemented `Column::replace` manually for no apparent reason.

## Solution

- use `Column::replace` and add a test expecting the correct drop count

---

## Changelog

- `World::insert_resource_by_id` will now correctly drop the old resource value, if one already existed
2022-08-09 18:05:43 +00:00
ira
992681b59b Make Resource trait opt-in, requiring #[derive(Resource)] V2 (#5577)
*This PR description is an edited copy of #5007, written by @alice-i-cecile.*
# Objective
Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds.

While ergonomic, this results in several drawbacks:

* it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource
* it is challenging to discover if a type is intended to be used as a resource
* we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component).
* dependencies can use the same Rust type as a resource in invisibly conflicting ways
* raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values
* we cannot capture a definitive list of possible resources to display to users in an editor
## Notes to reviewers
 * Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits.
   *ira: My commits are not as well organized :')*
 * I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does.
 * I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981.

## Changelog
`Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro.

## Migration Guide
Add `#[derive(Resource)]` to all types you are using as a resource.

If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics.

`ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing.
Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead.


Co-authored-by: Alice <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-08-08 21:36:35 +00:00
Rob Parrett
cfee0e882e Fix various typos (#5417)
## Objective

- Fix some typos

## Solution

- Fix em. 
- My favorite was `maxizimed`
2022-07-21 20:46:54 +00:00
François
0fa499a7d0 rename send_default_event to send_event_default on world (#5383)
after #5355, three methods were added on world:
* `send_event`
* `send_event_batch`
* `send_default_event`

rename `send_default_event` to `send_event_default` for better discoverability
2022-07-19 22:28:05 +00:00
Aevyrie
282f8ed0b9 Add helpers to send Events from World (#5355)
# Objective

- With access to `World`, it's not obvious how to send an event.
- This is especially useful if you are writing a `Command` that needs to send an `Event`.
- `Events` are a first-class construct in bevy, even though they are just `Resources` under the hood. Their methods should be discoverable.

## Solution

- Provide a simple helpers to send events through `Res<Events<T>>`.
---

## Changelog

> `send_event`, `send_default_event`, and `send_event_batch` methods added to `World`.
2022-07-19 20:54:03 +00:00
Obdzen
cf200f09dd Fix typo in Word::get_by_id docs (#5246)
I believe this should read `immutable` not `mutable`



Co-authored-by: Obdzen <108854527+Obdzen@users.noreply.github.com>
2022-07-07 15:25:17 +00:00
Jakob Hellermann
d38a8dfdd7 add more SAFETY comments and lint for missing ones in bevy_ecs (#4835)
# Objective

`SAFETY` comments are meant to be placed before `unsafe` blocks and should contain the reasoning of why in this case the usage of unsafe is okay. This is useful when reading the code because it makes it clear which assumptions are required for safety, and makes it easier to spot possible unsoundness holes. It also forces the code writer to think of something to write and maybe look at the safety contracts of any called unsafe methods again to double-check their correct usage.

There's a clippy lint called `undocumented_unsafe_blocks` which warns when using a block without such a comment. 

## Solution

- since clippy expects `SAFETY` instead of `SAFE`, rename those
- add `SAFETY` comments in more places
- for the last remaining 3 places, add an `#[allow()]` and `// TODO` since I wasn't comfortable enough with the code to justify their safety
- add ` #![warn(clippy::undocumented_unsafe_blocks)]` to `bevy_ecs`


### Note for reviewers

The first commit only renames `SAFETY` to `SAFE` so it doesn't need a thorough review.
cb042a416e..55cef2d6fa is the diff for all other changes.

### Safety comments where I'm not too familiar with the code

774012ece5/crates/bevy_ecs/src/entity/mod.rs (L540-L546)

774012ece5/crates/bevy_ecs/src/world/entity_ref.rs (L249-L252)

### Locations left undocumented with a `TODO` comment

5dde944a30/crates/bevy_ecs/src/schedule/executor_parallel.rs (L196-L199)

5dde944a30/crates/bevy_ecs/src/world/entity_ref.rs (L287-L289)

5dde944a30/crates/bevy_ecs/src/world/entity_ref.rs (L413-L415)

Co-authored-by: Jakob Hellermann <hellermann@sipgate.de>
2022-07-04 14:44:24 +00:00
Boxy
a1a07945d6 fix some memory leaks detected by miri (#4959)
The first leak:
```rust
    #[test]
    fn blob_vec_drop_empty_capacity() {
        let item_layout = Layout:🆕:<Foo>();
        let drop = drop_ptr::<Foo>;
        let _ = unsafe { BlobVec::new(item_layout, Some(drop), 0) };
    }
```
this is because we allocate the swap scratch in blobvec regardless of what the capacity is, but we only deallocate if capacity is > 0

The second leak:
```rust
    #[test]
    fn panic_while_overwriting_component() {
        let helper = DropTestHelper::new();

        let res = panic::catch_unwind(|| {
            let mut world = World::new();
            world
                .spawn()
                .insert(helper.make_component(true, 0))
                .insert(helper.make_component(false, 1));

            println!("Done inserting! Dropping world...");
        });

        let drop_log = helper.finish(res);

        assert_eq!(
            &*drop_log,
            [
                DropLogItem::Create(0),
                DropLogItem::Create(1),
                DropLogItem::Drop(0),
            ]
        );
    }
```
this is caused by us not running the drop impl on the to-be-inserted component if the drop impl of the overwritten component panics

---

managed to figure out where the leaks were by using this 10/10 command
```
cargo --quiet test --lib -- --list | sed 's/: test$//' | MIRIFLAGS="-Zmiri-disable-isolation" xargs -n1 cargo miri test --lib -- --exact
```
which runs every test one by one rather than all at once which let miri actually tell me which test had the leak 🙃
2022-07-01 21:54:28 +00:00
harudagondi
b3fa4790b7 Add ability to inspect entity's components (#5136)
# Objective

- Provide a way to see the components of an entity.
- Fixes #1467

## Solution

- Add `World::inspect_entity`. It accepts an `Entity` and returns a vector of `&ComponentInfo` that the entity has.
- Add `EntityCommands::log_components`. It logs the component names of the entity. (info level)

---

## Changelog

### Added
- Ability to inspect components of an entity through `World::inspect_entity` or `EntityCommands::log_components`
2022-06-30 15:23:09 +00:00
Mike
510ce5e832 fix resource not found error message (#5128)
There are some outdated error messages for when a resource is not found. It references `add_resource` and `add_non_send_resource` which were renamed to `insert_resource` and `insert_non_send_resource`.
2022-06-29 02:29:51 +00:00
Garett Cooper
fa56a5cd51 Add component_id function to World and Components (#5066)
# Objective

- Simplify the process of obtaining a `ComponentId` instance corresponding to a `Component`.
- Resolves #5060.

## Solution

- Add a `component_id::<T: Component>(&self)` function to both `World` and `Components` to retrieve the `ComponentId` associated with `T` from a immutable reference.

---

## Changelog

- Added `World::component_id::<C>()` and `Components::component_id::<C>()` to retrieve a `Component`'s corresponding `ComponentId` if it exists.
2022-06-25 20:41:54 +00:00
James Liu
c988264180 Mark mutable APIs under ECS storage as pub(crate) (#5065)
# Objective
Closes #1557. Partially addresses #3362.

Cleanup the public facing API for storage types. Most of these APIs are difficult to use safely when directly interfacing with these types, and is also currently impossible to interact with in normal ECS use as there is no `World::storages_mut`. The majority of these types should be easy enough to read, and perhaps mutate the contents, but never structurally altered without the same checks in the rest of bevy_ecs code. This both cleans up the public facing types and helps use unused code detection to remove a few of the APIs we're not using internally. 

## Solution

 - Mark all APIs that take `&mut T` under `bevy_ecs::storage` as `pub(crate)` or `pub(super)`
 - Cleanup after it all.

Entire type visibility changes:

 - `BlobVec` is `pub(super)`, only storage code should be directly interacting with it.
 - `SparseArray` is now `pub(crate)` for the entire type. It's an implementation detail for `Table` and `(Component)SparseSet`.
 - `TableMoveResult` is now `pub(crate)

---

## Changelog
TODO

## Migration Guide
Dear God, I hope not.
2022-06-21 20:35:26 +00:00
Jakob Hellermann
60584139de untyped APIs for components and resources (#4447)
# Objective

Even if bevy itself does not provide any builtin scripting or modding APIs, it should have the foundations for building them yourself.
For that it should be enough to have APIs that are not tied to the actual rust types with generics, but rather accept `ComponentId`s and `bevy_ptr` ptrs.

## Solution

Add the following APIs to bevy
```rust
fn EntityRef::get_by_id(ComponentId) -> Option<Ptr<'w>>;
fn EntityMut::get_by_id(ComponentId) -> Option<Ptr<'_>>;
fn EntityMut::get_mut_by_id(ComponentId) -> Option<MutUntyped<'_>>;

fn World::get_resource_by_id(ComponentId) -> Option<Ptr<'_>>;
fn World::get_resource_mut_by_id(ComponentId) -> Option<MutUntyped<'_>>;

// Safety: `value` must point to a valid value of the component
unsafe fn World::insert_resource_by_id(ComponentId, value: OwningPtr);

fn ComponentDescriptor::new_with_layout(..) -> Self;
fn World::init_component_with_descriptor(ComponentDescriptor) -> ComponentId;
```

~~This PR would definitely benefit from #3001 (lifetime'd pointers) to make sure that the lifetimes of the pointers are valid and the my-move pointer in `insert_resource_by_id` could be an `OwningPtr`, but that can be adapter later if/when #3001 is merged.~~

### Not in this PR
- inserting components on entities (this is very tied to types with bundles and the `BundleInserter`)
- an untyped version of a query (needs good API design, has a large implementation complexity, can be done in a third-party crate)

Co-authored-by: Jakob Hellermann <hellermann@sipgate.de>
2022-05-30 15:32:47 +00:00
Jakob Hellermann
1e322d9f76 bevy_ptr standalone crate (#4653)
# Objective

The pointer types introduced in #3001 are useful not just in `bevy_ecs`, but also in crates like `bevy_reflect` (#4475) or even outside of bevy.

## Solution

Extract `Ptr<'a>`, `PtrMut<'a>`, `OwnedPtr<'a>`, `ThinSlicePtr<'a, T>` and `UnsafeCellDeref` from `bevy_ecs::ptr` into `bevy_ptr`.

**Note:** `bevy_ecs` still reexports the `bevy_ptr` as `bevy_ecs::ptr` so that crates like `bevy_transform` can use the `Bundle` derive without needing to depend on `bevy_ptr` themselves.
2022-05-04 19:16:10 +00:00
TheRawMeatball
73c78c3667 Use lifetimed, type erased pointers in bevy_ecs (#3001)
# Objective

`bevy_ecs` has large amounts of unsafe code which is hard to get right and makes it difficult to audit for soundness.

## Solution

Introduce lifetimed, type-erased pointers: `Ptr<'a>` `PtrMut<'a>` `OwningPtr<'a>'` and `ThinSlicePtr<'a, T>` which are newtypes around a raw pointer with a lifetime and conceptually representing strong invariants about the pointee and validity of the pointer.

The process of converting bevy_ecs to use these has already caught multiple cases of unsound behavior.

## Changelog

TL;DR for release notes: `bevy_ecs` now uses lifetimed, type-erased pointers internally, significantly improving safety and legibility without sacrificing performance. This should have approximately no end user impact, unless you were meddling with the (unfortunately public) internals of `bevy_ecs`.

- `Fetch`, `FilterFetch` and `ReadOnlyFetch` trait no longer have a `'state` lifetime
    - this was unneeded
- `ReadOnly/Fetch` associated types on `WorldQuery` are now on a new `WorldQueryGats<'world>` trait
    - was required to work around lack of Generic Associated Types (we wish to express `type Fetch<'a>: Fetch<'a>`)
- `derive(WorldQuery)` no longer requires `'w` lifetime on struct
    - this was unneeded, and improves the end user experience
- `EntityMut::get_unchecked_mut` returns `&'_ mut T` not `&'w mut T`
    - allows easier use of unsafe API with less footguns, and can be worked around via lifetime transmutery as a user
- `Bundle::from_components` now takes a `ctx` parameter to pass to the `FnMut` closure
    - required because closure return types can't borrow from captures
- `Fetch::init` takes `&'world World`, `Fetch::set_archetype` takes `&'world Archetype` and `&'world Tables`, `Fetch::set_table` takes `&'world Table`
    - allows types implementing `Fetch` to store borrows into world
- `WorldQuery` trait now has a `shrink` fn to shorten the lifetime in `Fetch::<'a>::Item`
    - this works around lack of subtyping of assoc types, rust doesnt allow you to turn `<T as Fetch<'static>>::Item'` into `<T as Fetch<'a>>::Item'`
    - `QueryCombinationsIter` requires this
- Most types implementing `Fetch` now have a lifetime `'w`
    - allows the fetches to store borrows of world data instead of using raw pointers

## Migration guide

- `EntityMut::get_unchecked_mut` returns a more restricted lifetime, there is no general way to migrate this as it depends on your code
- `Bundle::from_components` implementations must pass the `ctx` arg to `func`
- `Bundle::from_components` callers have to use a fn arg instead of closure captures for borrowing from world
- Remove lifetime args on `derive(WorldQuery)` structs as it is nonsensical
- `<Q as WorldQuery>::ReadOnly/Fetch` should be changed to either `RO/QueryFetch<'world>` or `<Q as WorldQueryGats<'world>>::ReadOnly/Fetch`
- `<F as Fetch<'w, 's>>` should be changed to `<F as Fetch<'w>>`
- Change the fn sigs of `Fetch::init/set_archetype/set_table` to match respective trait fn sigs
- Implement the required `fn shrink` on any `WorldQuery` implementations
- Move assoc types `Fetch` and `ReadOnlyFetch` on `WorldQuery` impls to `WorldQueryGats` impls
- Pass an appropriate `'world` lifetime to whatever fetch struct you are for some reason using

### Type inference regression

in some cases rustc may give spurrious errors when attempting to infer the `F` parameter on a query/querystate this can be fixed by manually specifying the type, i.e. `QueryState:🆕:<_, ()>(world)`. The error is rather confusing:

```rust=
error[E0271]: type mismatch resolving `<() as Fetch<'_>>::Item == bool`
    --> crates/bevy_pbr/src/render/light.rs:1413:30
     |
1413 |             main_view_query: QueryState::new(world),
     |                              ^^^^^^^^^^^^^^^ expected `bool`, found `()`
     |
     = note: required because of the requirements on the impl of `for<'x> FilterFetch<'x>` for `<() as WorldQueryGats<'x>>::Fetch`
note: required by a bound in `bevy_ecs::query::QueryState::<Q, F>::new`
    --> crates/bevy_ecs/src/query/state.rs:49:32
     |
49   |     for<'x> QueryFetch<'x, F>: FilterFetch<'x>,
     |                                ^^^^^^^^^^^^^^^ required by this bound in `bevy_ecs::query::QueryState::<Q, F>::new`
```

---

Made with help from @BoxyUwU and @alice-i-cecile 

Co-authored-by: Boxy <supbscripter@gmail.com>
2022-04-27 23:44:06 +00:00
François
8630b194dc add more logs when despawning entities (#3851)
# Objective

- Provide more information when despawning an entity

## Solution

- Add a debug log when despawning an entity
- Add spans to the recursive ways of despawning an entity

```sh
RUST_LOG=debug cargo run --example panic --features trace
# RUST_LOG=debug needed to show debug logs from bevy_ecs
# --features trace needed to have the extra spans
...

DEBUG bevy_app:frame:stage{name=Update}:system_commands{name="panic::despawn_parent"}:command{name="DespawnRecursive" entity=0v0}: bevy_ecs::world: Despawning entity 1v0
DEBUG bevy_app:frame:stage{name=Update}:system_commands{name="panic::despawn_parent"}:command{name="DespawnRecursive" entity=0v0}: bevy_ecs::world: Despawning entity 0v0
```
2022-04-13 23:35:28 +00:00
Boxy
dba7790012 REMOVE unsound lifetime annotations on EntityMut (#4096)
Fixes #3408
#3001 also solves this but I dont see it getting merged any time soon so...
# Objective
make bevy ecs a lil bit less unsound

## Solution
make `EntityMut::get_component_mut` return borrows from self instead of `'w`
2022-04-04 21:33:33 +00:00
Daniel McNab
aca7fc1854 Remove outdated perf comments (#4374)
# Objective

- The perf comments, added (by me) in https://github.com/bevyengine/bevy/pull/1349, became outdated once the initialisation call started to take an exclusive reference, (presumably in https://github.com/bevyengine/bevy/pull/1525).
- They have been naïvely transferred along ever since

## Solution

- Remove them
2022-03-31 20:43:00 +00:00
Boxy
637a149910 unsafeify World::entities_mut (#4093)
# Objective
make bevy ecs a lil bit less unsound

## Solution
make unsound API unsafe so that there is an unsafe block to blame:

```rust
use bevy_ecs::prelude::*;

#[derive(Debug, Component)]
struct Foo(u8);

fn main() {
    let mut world = World::new();
    let e1 = world.spawn().id();
    let e2 = world.spawn().insert(Foo(2)).id();
    world.entities_mut().meta[0] = world.entities_mut().meta[1].clone();
    let foo = world.entity(e1).get::<Foo>().unwrap();
    // whoo i love having components i dont have
    dbg!(foo);
}
```

This is not _strictly_ speaking UB, however: 
- `Query::get_multiple` cannot work if this is allowed
- bevy_ecs is a pile of unsafe code whose soundness generally depends on the world being in a "correct" state with "no funny business" so it seems best to disallow this
- it is trivial to get bevy to panic inside of functions with safety invariants that have been violated (the entity location is not valid)
- it seems to violate what the safety invariant on `Entities::flush` is trying to ensure
2022-03-30 23:52:45 +00:00
Boxy
050d2b7f00 yeet World::components_mut >:( (#4092)
# Objective
make bevy ecs a lil bit less unsound
## Solution
yeet unsound API `World::components_mut`:
```rust
use bevy_ecs::prelude::*;

#[derive(Component)]
struct Foo(u8);

#[derive(Debug, Component)]
struct Bar([u8; 100]);

fn main() {
    let mut world = World::new();
    let e = world.spawn().insert(Foo(0)).id();
    *world.components_mut() = Default::default();
    let bar = world.entity_mut(e).remove::<Bar>().unwrap();
    // oopsies reading memory copied from outside allocation
    dbg!(bar);
}
```
2022-03-21 23:43:08 +00:00
Alice Cecile
557ab9897a Make get_resource (and friends) infallible (#4047)
# Objective

- In the large majority of cases, users were calling `.unwrap()` immediately after `.get_resource`.
- Attempting to add more helpful error messages here resulted in endless manual boilerplate (see #3899 and the linked PRs).

## Solution

- Add an infallible variant named `.resource` and so on.
- Use these infallible variants over `.get_resource().unwrap()` across the code base.

## Notes

I did not provide equivalent methods on `WorldCell`, in favor of removing it entirely in #3939.

## Migration Guide

Infallible variants of `.get_resource` have been added that implicitly panic, rather than needing to be unwrapped.

Replace `world.get_resource::<Foo>().unwrap()` with `world.resource::<Foo>()`.

## Impact

- `.unwrap` search results before: 1084
- `.unwrap` search results after: 942
- internal `unwrap_or_else` calls added: 4
- trivial unwrap calls removed from tests and code: 146
- uses of the new `try_get_resource` API: 11
- percentage of the time the unwrapping API was used internally: 93%
2022-02-27 22:37:18 +00:00
Alice Cecile
330160cf14 SystemState usage docs (#3783)
# Objective

- `SystemStates` rock for dealing with exclusive world access, but are hard to figure out how to use.
- Fixes #3341.

## Solution

- Clearly document how to use `SystemState`, and why they're useful as an end-user.
2022-02-15 21:53:52 +00:00