Commit Graph

168 Commits

Author SHA1 Message Date
Vic
8723096d57 reexport entity set collections in entity module (#18413)
# Objective

Unlike for their helper typers, the import paths for
`unique_array::UniqueEntityArray`, `unique_slice::UniqueEntitySlice`,
`unique_vec::UniqueEntityVec`, `hash_set::EntityHashSet`,
`hash_map::EntityHashMap`, `index_set::EntityIndexSet`,
`index_map::EntityIndexMap` are quite redundant.

When looking at the structure of `hashbrown`, we can also see that while
both `HashSet` and `HashMap` have their own modules, the main types
themselves are re-exported to the crate level.

## Solution

Re-export the types in their shared `entity` parent module, and simplify
the imports where they're used.
2025-03-30 10:24:00 +02:00
Gino Valente
c2854a2a05
bevy_reflect: Deprecate PartialReflect::clone_value (#18284)
# Objective

#13432 added proper reflection-based cloning. This is a better method
than cloning via `clone_value` for reasons detailed in the description
of that PR. However, it may not be immediately apparent to users why one
should be used over the other, and what the gotchas of `clone_value`
are.

## Solution

This PR marks `PartialReflect::clone_value` as deprecated, with the
deprecation notice pointing users to `PartialReflect::reflect_clone`.
However, it also suggests using a new method introduced in this PR:
`PartialReflect::to_dynamic`.

`PartialReflect::to_dynamic` is essentially a renaming of
`PartialReflect::clone_value`. By naming it `to_dynamic`, we make it
very obvious that what's returned is a dynamic type. The one caveat to
this is that opaque types still use `reflect_clone` as they have no
corresponding dynamic type.

Along with changing the name, the method is now optional, and comes with
a default implementation that calls out to the respective reflection
subtrait method. This was done because there was really no reason to
require manual implementors provide a method that almost always calls
out to a known set of methods.

Lastly, to make this default implementation work, this PR also did a
similar thing with the `clone_dynamic ` methods on the reflection
subtraits. For example, `Struct::clone_dynamic` has been marked
deprecated and is superseded by `Struct::to_dynamic_struct`. This was
necessary to avoid the "multiple names in scope" issue.

### Open Questions

This PR maintains the original signature of `clone_value` on
`to_dynamic`. That is, it takes `&self` and returns `Box<dyn
PartialReflect>`.

However, in order for this to work, it introduces a panic if the value
is opaque and doesn't override the default `reflect_clone`
implementation.

One thing we could do to avoid the panic would be to make the conversion
fallible, either returning `Option<Box<dyn PartialReflect>>` or
`Result<Box<dyn PartialReflect>, ReflectCloneError>`.

This makes using the method a little more involved (i.e. users have to
either unwrap or handle the rare possibility of an error), but it would
set us up for a world where opaque types don't strictly need to be
`Clone`. Right now this bound is sort of implied by the fact that
`clone_value` is a required trait method, and the default behavior of
the macro is to use `Clone` for opaque types.

Alternatively, we could keep the signature but make the method required.
This maintains that implied bound where manual implementors must provide
some way of cloning the value (or YOLO it and just panic), but also
makes the API simpler to use.

Finally, we could just leave it with the panic. It's unlikely this would
occur in practice since our macro still requires `Clone` for opaque
types, and thus this would only ever be an issue if someone were to
manually implement `PartialReflect` without a valid `to_dynamic` or
`reflect_clone` method.

## Testing

You can test locally using the following command:

```
cargo test --package bevy_reflect --all-features
```

---

## Migration Guide

`PartialReflect::clone_value` is being deprecated. Instead, use
`PartialReflect::to_dynamic` if wanting to create a new dynamic instance
of the reflected value. Alternatively, use
`PartialReflect::reflect_clone` to attempt to create a true clone of the
underlying value.

Similarly, the following methods have been deprecated and should be
replaced with these alternatives:
- `Array::clone_dynamic` → `Array::to_dynamic_array`
- `Enum::clone_dynamic` → `Enum::to_dynamic_enum`
- `List::clone_dynamic` → `List::to_dynamic_list`
- `Map::clone_dynamic` → `Map::to_dynamic_map`
- `Set::clone_dynamic` → `Set::to_dynamic_set`
- `Struct::clone_dynamic` → `Struct::to_dynamic_struct`
- `Tuple::clone_dynamic` → `Tuple::to_dynamic_tuple`
- `TupleStruct::clone_dynamic` → `TupleStruct::to_dynamic_tuple_struct`
2025-03-14 19:33:57 +00:00
Benjamin Brienen
c3ff6d4136
Fix non-crate typos (#18219)
# Objective

Correct spelling

## Solution

Fix typos, specifically ones that I found in folders other than /crates

## Testing

CI

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-03-11 06:17:48 +00:00
Eagster
ed7b366b24
Deprecate insert_or_spawn function family (#18147)
# Objective

Based on #18054, this PR builds on #18035 to deprecate:

- `Commands::insert_or_spawn_batch`
- `Entities::alloc_at_without_replacement`
- `Entities::alloc_at`
- `World::insert_or_spawn_batch`
- `World::insert_or_spawn_batch_with_caller`

## Testing

Just deprecation, so no new tests. Note that as of writing #18035 is
still under testing and review.

## Open Questions

- [x] Should `entity::AllocAtWithoutReplacement` be deprecated? It is
internal and only used in `Entities::alloc_at_without_replacement`.
**EDIT:** Now deprecated.

## Migration Guide

The following functions have been deprecated:

- `Commands::insert_or_spawn_batch`
- `World::insert_or_spawn_batch`
- `World::insert_or_spawn_batch_with_caller`

These functions, when used incorrectly, can cause major performance
problems and are generally viewed as anti-patterns and foot guns. These
are planned to be removed altogether in 0.17.

Instead of these functions consider doing one of the following:

Option A) Instead of despawing entities and re-spawning them at a
particular id, insert the new `Disabled` component without despawning
the entity, and use `try_insert_batch` or `insert_batch` and remove
`Disabled` instead of re-spawning it.

Option B) Instead of giving special meaning to an entity id, simply use
`spawn_batch` and ensure entity references are valid when despawning.

---------

Co-authored-by: JaySpruce <jsprucebruce@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-03-06 17:04:16 +00:00
Carter Anderson
a530c07bc5
Preserve spawned RelationshipTarget order and other improvements (#17858)
Fixes #17720

## Objective

Spawning RelationshipTargets from scenes currently fails to preserve
RelationshipTarget ordering (ex: `Children` has an arbitrary order).
This is because it uses the normal hook flow to set up the collection,
which means we are pushing onto the collection in _spawn order_ (which
is currently in archetype order, which will often produce mismatched
orderings).

We need to preserve the ordering in the original RelationshipTarget
collection. Ideally without expensive checking / fixups.

## Solution

One solution would be to spawn in hierarchy-order. However this gets
complicated as there can be multiple hierarchies, and it also means we
can't spawn in more cache-friendly orders (ex: the current per-archetype
spawning, or future even-smarter per-table spawning). Additionally,
same-world cloning has _slightly_ more nuanced needs (ex: recursively
clone linked relationships, while maintaining _original_ relationships
outside of the tree via normal hooks).

The preferred approach is to directly spawn the remapped
RelationshipTarget collection, as this trivially preserves the ordering.
Unfortunately we can't _just_ do that, as when we spawn the children
with their Relationships (ex: `ChildOf`), that will insert a duplicate.

We could "fixup" the collection retroactively by just removing the back
half of duplicates, but this requires another pass / more lookups /
allocating twice as much space. Additionally, it becomes complicated
because observers could insert additional children, making it harder
(aka more expensive) to determine which children are dupes and which are
not.

The path I chose is to support "opting out" of the relationship target
hook in the contexts that need that, as this allows us to just cheaply
clone the mapped collection. The relationship hook can look for this
configuration when it runs and skip its logic when that happens. A
"simple" / small-amount-of-code way to do this would be to add a "skip
relationship spawn" flag to World. Sadly, any hook / observer that runs
_as the result of an insert_ would also read this flag. We really need a
way to scope this setting to a _specific_ insert.

Therefore I opted to add a new `RelationshipInsertHookMode` enum and an
`entity.insert_with_relationship_insert_hook_mode` variant. Obviously
this is verbose and ugly. And nobody wants _more_ insert variants. But
sadly this was the best I could come up with from a performance and
capability perspective. If you have alternatives let me know!

There are three variants:

1. `RelationshipInsertHookMode::Run`: always run relationship insert
hooks (this is the default)
2. `RelationshipInsertHookMode::Skip`: do not run any relationship
insert hooks for this insert (this is used by spawner code)
3. `RelationshipInsertHookMode::RunIfNotLinked`: only run hooks for
_unlinked_ relationships (this is used in same-world recursive entity
cloning to preserve relationships outside of the deep-cloned tree)

Note that I have intentionally only added "insert with relationship hook
mode" variants to the cases we absolutely need (everything else uses the
default `Run` mode), just to keep the code size in check. I do not think
we should add more without real _very necessary_ use cases.

I also made some other minor tweaks:

1. I split out `SourceComponent` from `ComponentCloneCtx`. Reading the
source component no longer needlessly blocks mutable access to
`ComponentCloneCtx`.
2. Thanks to (1), I've removed the `RefCell` wrapper over the cloned
component queue.
3. (1) also allowed me to write to the EntityMapper while queuing up
clones, meaning we can reserve entities during the component clone and
write them to the mapper _before_ inserting the component, meaning
cloned collections can be mapped on insert.
4. I've removed the closure from `write_target_component_ptr` to
simplify the API / make it compatible with the split `SourceComponent`
approach.
5. I've renamed `EntityCloner::recursive` to
`EntityCloner::linked_cloning` to connect that feature more directly
with `RelationshipTarget::LINKED_SPAWN`
6. I've removed `EntityCloneBehavior::RelationshipTarget`. This was
always intended to be temporary, and this new behavior removes the need
for it.

---------

Co-authored-by: Viktor Gustavsson <villor94@gmail.com>
2025-03-05 22:18:57 +00:00
Tim Overbeek
ccb7069e7f
Change ChildOf to Childof { parent: Entity} and support deriving Relationship and RelationshipTarget with named structs (#17905)
# Objective

fixes #17896 

## Solution

Change ChildOf ( Entity ) to ChildOf { parent: Entity }

by doing this we also allow users to use named structs for relationship
derives, When you have more than 1 field in a struct with named fields
the macro will look for a field with the attribute #[relationship] and
all of the other fields should implement the Default trait. Unnamed
fields are still supported.

When u have a unnamed struct with more than one field the macro will
fail.
Do we want to support something like this ? 

```rust
 #[derive(Component)]
 #[relationship_target(relationship = ChildOf)]
 pub struct Children (#[relationship] Entity, u8);
```
I could add this, it but doesn't seem nice.
## Testing

crates/bevy_ecs - cargo test


## Showcase


```rust

use bevy_ecs::component::Component;
use bevy_ecs::entity::Entity;

 #[derive(Component)]
 #[relationship(relationship_target = Children)]
 pub struct ChildOf {
     #[relationship]
     pub parent: Entity,
     internal: u8,
 };

 #[derive(Component)]
 #[relationship_target(relationship = ChildOf)]
 pub struct Children {
     children: Vec<Entity>
 };

```

---------

Co-authored-by: Tim Overbeek <oorbecktim@Tims-MacBook-Pro.local>
Co-authored-by: Tim Overbeek <oorbecktim@c-001-001-042.client.nl.eduvpn.org>
Co-authored-by: Tim Overbeek <oorbecktim@c-001-001-059.client.nl.eduvpn.org>
Co-authored-by: Tim Overbeek <oorbecktim@c-001-001-054.client.nl.eduvpn.org>
Co-authored-by: Tim Overbeek <oorbecktim@c-001-001-027.client.nl.eduvpn.org>
2025-02-27 19:22:17 +00:00
Ruslan Baynazarov
c7531074bc
Improve cubic segment bezier functionality (#17645)
# Objective

- Fixes #17642

## Solution

- Implemented method `new_bezier(points: [P; 4]) -> Self` for
`CubicSegment<P>`
- Old implementation of `new_bezier` is now `new_bezier_easing(p1: impl
Into<Vec2>, p2: impl Into<Vec2>) -> Self` (**breaking change**)
- ~~added method `new_bezier_with_anchor`, which can make a bezier curve
between two points with one control anchor~~
- added methods `iter_positions`, `iter_velocities`,
`iter_accelerations`, the same as in `CubicCurve` (**copied code,
potentially can be reduced)**
- bezier creation logic is moved from `CubicCurve` to `CubicSegment`,
removing the unneeded allocation

## Testing

- Did you test these changes? If so, how?
  - Run tests inside `crates/bevy_math/`
  - Tested the functionality in my project
- Are there any parts that need more testing?
  - Did not run `cargo test` on the whole bevy directory because of OOM
- Performance improvements are expected when creating `CubicCurve` with
`new_bezier` and `new_bezier_easing`, but not tested
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
  - Use in any code that works created `CubicCurve::new_bezier`
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
  - I don't think relevant

---

## Showcase

```rust
// Imagine a car goes towards a local target

// Create a simple `CubicSegment`, without using heap
let planned_path = CubicSegment::new_bezier([
    car_pos,
    car_pos + car_dir * turn_radius,
    target_point - target_dir * turn_radius,
    target_point,
]);

// Check if the planned path itersect other entities
for pos in planned_path.iter_positions(8) {
   // do some collision checks
}
```

## Migration Guide

> This section is optional. If there are no breaking changes, you can
delete this section.

- Replace `CubicCurve::new_bezier` with `CubicCurve::new_bezier_easing`
2025-02-26 20:36:54 +00:00
Zachary Harrold
20813aed64
Handle TriggerTargets that are combinations for components/entities (#18024)
# Objective

* Fixes https://github.com/bevyengine/bevy/issues/14074
* Applies CI fixes for #16326

It is currently not possible to issues a trigger that targets a specific
list of components AND a specific list of entities

## Solution

We can now use `((A, B), (entity_1, entity_2))` as a trigger target, as
well as the reverse

## Testing

Added a unit test.

The triggering rules for observers are quite confusing:

Triggers once per entity target

For each entity target, an observer system triggers if any of its
components matches the trigger target components (but it triggers at
most once, since we use an internal counter to make sure that an
observer can run at most once per entity target)

(copied from #14563)
(copied from #16326)

## Notes

All credit to @BenjaminBrienen and @cBournhonesque! Just applying a
small fix to this PR so it can be merged.

---------

Co-authored-by: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Co-authored-by: Christian Hughes <xdotdash@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-02-24 23:57:34 +00:00
Zachary Harrold
5241e09671
Upgrade to Rust Edition 2024 (#17967)
# Objective

- Fixes #17960

## Solution

- Followed the [edition upgrade
guide](https://doc.rust-lang.org/edition-guide/editions/transitioning-an-existing-project-to-a-new-edition.html)

## Testing

- CI

---

## Summary of Changes

### Documentation Indentation

When using lists in documentation, proper indentation is now linted for.
This means subsequent lines within the same list item must start at the
same indentation level as the item.

```rust
/* Valid */
/// - Item 1
///   Run-on sentence.
/// - Item 2
struct Foo;

/* Invalid */
/// - Item 1
///     Run-on sentence.
/// - Item 2
struct Foo;
```

### Implicit `!` to `()` Conversion

`!` (the never return type, returned by `panic!`, etc.) no longer
implicitly converts to `()`. This is particularly painful for systems
with `todo!` or `panic!` statements, as they will no longer be functions
returning `()` (or `Result<()>`), making them invalid systems for
functions like `add_systems`. The ideal fix would be to accept functions
returning `!` (or rather, _not_ returning), but this is blocked on the
[stabilisation of the `!` type
itself](https://doc.rust-lang.org/std/primitive.never.html), which is
not done.

The "simple" fix would be to add an explicit `-> ()` to system
signatures (e.g., `|| { todo!() }` becomes `|| -> () { todo!() }`).
However, this is _also_ banned, as there is an existing lint which (IMO,
incorrectly) marks this as an unnecessary annotation.

So, the "fix" (read: workaround) is to put these kinds of `|| -> ! { ...
}` closuers into variables and give the variable an explicit type (e.g.,
`fn()`).

```rust
// Valid
let system: fn() = || todo!("Not implemented yet!");
app.add_systems(..., system);

// Invalid
app.add_systems(..., || todo!("Not implemented yet!"));
```

### Temporary Variable Lifetimes

The order in which temporary variables are dropped has changed. The
simple fix here is _usually_ to just assign temporaries to a named
variable before use.

### `gen` is a keyword

We can no longer use the name `gen` as it is reserved for a future
generator syntax. This involved replacing uses of the name `gen` with
`r#gen` (the raw-identifier syntax).

### Formatting has changed

Use statements have had the order of imports changed, causing a
substantial +/-3,000 diff when applied. For now, I have opted-out of
this change by amending `rustfmt.toml`

```toml
style_edition = "2021"
```

This preserves the original formatting for now, reducing the size of
this PR. It would be a simple followup to update this to 2024 and run
`cargo fmt`.

### New `use<>` Opt-Out Syntax

Lifetimes are now implicitly included in RPIT types. There was a handful
of instances where it needed to be added to satisfy the borrow checker,
but there may be more cases where it _should_ be added to avoid
breakages in user code.

### `MyUnitStruct { .. }` is an invalid pattern

Previously, you could match against unit structs (and unit enum
variants) with a `{ .. }` destructuring. This is no longer valid.

### Pretty much every use of `ref` and `mut` are gone

Pattern binding has changed to the point where these terms are largely
unused now. They still serve a purpose, but it is far more niche now.

### `iter::repeat(...).take(...)` is bad

New lint recommends using the more explicit `iter::repeat_n(..., ...)`
instead.

## Migration Guide

The lifetimes of functions using return-position impl-trait (RPIT) are
likely _more_ conservative than they had been previously. If you
encounter lifetime issues with such a function, please create an issue
to investigate the addition of `+ use<...>`.

## Notes

- Check the individual commits for a clearer breakdown for what
_actually_ changed.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2025-02-24 03:54:47 +00:00
BD103
63e0f794d1
Enable nonstandard_macro_braces and enforce [] for children! (#17974)
# Objective

-
[`nonstandard_macro_braces`](https://rust-lang.github.io/rust-clippy/master/index.html#nonstandard_macro_braces)
is a Clippy lint that enforces what braces certain known macros are
allowed to use.
  - For instance, requiring `println!()` instead of `println!{}`.
- I started working on this after seeing
https://github.com/TheBevyFlock/bevy_cli/issues/277.

## Solution

- Enable `nonstandard_macro_braces` in the workspace.
- Configure Clippy so it enforces `[]` braces for `children!`.

## Testing

1. Create `examples/clippy_test.rs`.
2. Paste the following code:

```rust
//! Some docs woooooooo

use bevy::prelude::*;

fn main() {
    let _ = children!(Name::new("Foo"));
}
```

3. Run `cargo clippy --example clippy_test`.
4. Ensure the following warning is emitted:

```sh
warning: use of irregular braces for `children!` macro
 --> examples/clippy_test.rs:6:13
  |
6 |     let _ = children!(Name::new("Foo"));
  |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider writing: `children![Name::new("Foo")]`
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#nonstandard_macro_braces
  = note: requested on the command line with `-W clippy::nonstandard-macro-braces`

warning: `bevy` (example "clippy_test") generated 1 warning (run `cargo clippy --fix --example "clippy_test"` to apply 1 suggestion)
```
2025-02-22 01:54:49 +00:00
Carter Anderson
ea578415e1
Improved Spawn APIs and Bundle Effects (#17521)
## Objective

A major critique of Bevy at the moment is how boilerplatey it is to
compose (and read) entity hierarchies:

```rust
commands
    .spawn(Foo)
    .with_children(|p| {
        p.spawn(Bar).with_children(|p| {
            p.spawn(Baz);
        });
        p.spawn(Bar).with_children(|p| {
            p.spawn(Baz);
        });
    });
```

There is also currently no good way to statically define and return an
entity hierarchy from a function. Instead, people often do this
"internally" with a Commands function that returns nothing, making it
impossible to spawn the hierarchy in other cases (direct World spawns,
ChildSpawner, etc).

Additionally, because this style of API results in creating the
hierarchy bits _after_ the initial spawn of a bundle, it causes ECS
archetype changes (and often expensive table moves).

Because children are initialized after the fact, we also can't count
them to pre-allocate space. This means each time a child inserts itself,
it has a high chance of overflowing the currently allocated capacity in
the `RelationshipTarget` collection, causing literal worst-case
reallocations.

We can do better!

## Solution

The Bundle trait has been extended to support an optional
`BundleEffect`. This is applied directly to World immediately _after_
the Bundle has fully inserted. Note that this is
[intentionally](https://github.com/bevyengine/bevy/discussions/16920)
_not done via a deferred Command_, which would require repeatedly
copying each remaining subtree of the hierarchy to a new command as we
walk down the tree (_not_ good performance).

This allows us to implement the new `SpawnRelated` trait for all
`RelationshipTarget` impls, which looks like this in practice:

```rust
world.spawn((
    Foo,
    Children::spawn((
        Spawn((
            Bar,
            Children::spawn(Spawn(Baz)),
        )),
        Spawn((
            Bar,
            Children::spawn(Spawn(Baz)),
        )),
    ))
))
```

`Children::spawn` returns `SpawnRelatedBundle<Children, L:
SpawnableList>`, which is a `Bundle` that inserts `Children`
(preallocated to the size of the `SpawnableList::size_hint()`).
`Spawn<B: Bundle>(pub B)` implements `SpawnableList` with a size of 1.
`SpawnableList` is also implemented for tuples of `SpawnableList` (same
general pattern as the Bundle impl).

There are currently three built-in `SpawnableList` implementations:

```rust
world.spawn((
    Foo,
    Children::spawn((
        Spawn(Name::new("Child1")),   
        SpawnIter(["Child2", "Child3"].into_iter().map(Name::new),
        SpawnWith(|parent: &mut ChildSpawner| {
            parent.spawn(Name::new("Child4"));
            parent.spawn(Name::new("Child5"));
        })
    )),
))
```

We get the benefits of "structured init", but we have nice flexibility
where it is required!

Some readers' first instinct might be to try to remove the need for the
`Spawn` wrapper. This is impossible in the Rust type system, as a tuple
of "child Bundles to be spawned" and a "tuple of Components to be added
via a single Bundle" is ambiguous in the Rust type system. There are two
ways to resolve that ambiguity:

1. By adding support for variadics to the Rust type system (removing the
need for nested bundles). This is out of scope for this PR :)
2. Using wrapper types to resolve the ambiguity (this is what I did in
this PR).

For the single-entity spawn cases, `Children::spawn_one` does also
exist, which removes the need for the wrapper:

```rust
world.spawn((
    Foo,
    Children::spawn_one(Bar),
))
```

## This works for all Relationships

This API isn't just for `Children` / `ChildOf` relationships. It works
for any relationship type, and they can be mixed and matched!

```rust
world.spawn((
    Foo,
    Observers::spawn((
        Spawn(Observer::new(|trigger: Trigger<FuseLit>| {})),
        Spawn(Observer::new(|trigger: Trigger<Exploded>| {})),
    )),
    OwnerOf::spawn(Spawn(Bar))
    Children::spawn(Spawn(Baz))
))
```

## Macros

While `Spawn` is necessary to satisfy the type system, we _can_ remove
the need to express it via macros. The example above can be expressed
more succinctly using the new `children![X]` macro, which internally
produces `Children::spawn(Spawn(X))`:

```rust
world.spawn((
    Foo,
    children![
        (
            Bar,
            children![Baz],
        ),
        (
            Bar,
            children![Baz],
        ),
    ]
))
```

There is also a `related!` macro, which is a generic version of the
`children!` macro that supports any relationship type:

```rust
world.spawn((
    Foo,
    related!(Children[
        (
            Bar,
            related!(Children[Baz]),
        ),
        (
            Bar,
            related!(Children[Baz]),
        ),
    ])
))
```

## Returning Hierarchies from Functions

Thanks to these changes, the following pattern is now possible:

```rust
fn button(text: &str, color: Color) -> impl Bundle {
    (
        Node {
            width: Val::Px(300.),
            height: Val::Px(100.),
            ..default()
        },
        BackgroundColor(color),
        children![
            Text::new(text),
        ]
    )
}

fn ui() -> impl Bundle {
    (
        Node {
            width: Val::Percent(100.0),
            height: Val::Percent(100.0),
            ..default(),
        },
        children![
            button("hello", BLUE),
            button("world", RED),
        ]
    )
}

// spawn from a system
fn system(mut commands: Commands) {
    commands.spawn(ui());
}

// spawn directly on World
world.spawn(ui());
```

## Additional Changes and Notes

* `Bundle::from_components` has been split out into
`BundleFromComponents::from_components`, enabling us to implement
`Bundle` for types that cannot be "taken" from the ECS (such as the new
`SpawnRelatedBundle`).
* The `NoBundleEffect` trait (which implements `BundleEffect`) is
implemented for empty tuples (and tuples of empty tuples), which allows
us to constrain APIs to only accept bundles that do not have effects.
This is critical because the current batch spawn APIs cannot efficiently
apply BundleEffects in their current form (as doing so in-place could
invalidate the cached raw pointers). We could consider allocating a
buffer of the effects to be applied later, but that does have
performance implications that could offset the balance and value of the
batched APIs (and would likely require some refactors to the underlying
code). I've decided to be conservative here. We can consider relaxing
that requirement on those APIs later, but that should be done in a
followup imo.
* I've ported a few examples to illustrate real-world usage. I think in
a followup we should port all examples to the `children!` form whenever
possible (and for cases that require things like SpawnIter, use the raw
APIs).
* Some may ask "why not use the `Relationship` to spawn (ex:
`ChildOf::spawn(Foo)`) instead of the `RelationshipTarget` (ex:
`Children::spawn(Spawn(Foo))`)?". That _would_ allow us to remove the
`Spawn` wrapper. I've explicitly chosen to disallow this pattern.
`Bundle::Effect` has the ability to create _significant_ weirdness.
Things in `Bundle` position look like components. For example
`world.spawn((Foo, ChildOf::spawn(Bar)))` _looks and reads_ like Foo is
a child of Bar. `ChildOf` is in Foo's "component position" but it is not
a component on Foo. This is a huge problem. Now that `Bundle::Effect`
exists, we should be _very_ principled about keeping the "weird and
unintuitive behavior" to a minimum. Things that read like components
_should be the components they appear to be".

## Remaining Work

* The macros are currently trivially implemented using macro_rules and
are currently limited to the max tuple length. They will require a
proc_macro implementation to work around the tuple length limit.

## Next Steps

* Port the remaining examples to use `children!` where possible and raw
`Spawn` / `SpawnIter` / `SpawnWith` where the flexibility of the raw API
is required.

## Migration Guide

Existing spawn patterns will continue to work as expected.

Manual Bundle implementations now require a `BundleEffect` associated
type. Exisiting bundles would have no bundle effect, so use `()`.
Additionally `Bundle::from_components` has been moved to the new
`BundleFromComponents` trait.

```rust
// Before
unsafe impl Bundle for X {
    unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self {
    }
    /* remaining bundle impl here */
}

// After
unsafe impl Bundle for X {
    type Effect = ();
    /* remaining bundle impl here */
}

unsafe impl BundleFromComponents for X {
    unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self {
    }
}
```

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
Co-authored-by: Emerson Coskey <emerson@coskey.dev>
2025-02-09 23:32:56 +00:00
raldone01
1b7db895b7
Harden proc macro path resolution and add integration tests. (#17330)
This pr uses the `extern crate self as` trick to make proc macros behave
the same way inside and outside bevy.

# Objective

- Removes noise introduced by `crate as` in the whole bevy repo.
- Fixes #17004.
- Hardens proc macro path resolution.

## TODO

- [x] `BevyManifest` needs cleanup.
- [x] Cleanup remaining `crate as`.
- [x] Add proper integration tests to the ci.

## Notes

- `cargo-manifest-proc-macros` is written by me and based/inspired by
the old `BevyManifest` implementation and
[`bkchr/proc-macro-crate`](https://github.com/bkchr/proc-macro-crate).
- What do you think about the new integration test machinery I added to
the `ci`?
  More and better integration tests can be added at a later stage.
The goal of these integration tests is to simulate an actual separate
crate that uses bevy. Ideally they would lightly touch all bevy crates.

## Testing

- Needs RA test
- Needs testing from other users
- Others need to run at least `cargo run -p ci integration-test` and
verify that they work.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-02-09 19:45:45 +00:00
Carter Anderson
3c8fae2390
Improved Entity Mapping and Cloning (#17687)
Fixes #17535

Bevy's approach to handling "entity mapping" during spawning and cloning
needs some work. The addition of
[Relations](https://github.com/bevyengine/bevy/pull/17398) both
[introduced a new "duplicate entities" bug when spawning scenes in the
scene system](#17535) and made the weaknesses of the current mapping
system exceedingly clear:

1. Entity mapping requires _a ton_ of boilerplate (implement or derive
VisitEntities and VisitEntitesMut, then register / reflect MapEntities).
Knowing the incantation is challenging and if you forget to do it in
part or in whole, spawning subtly breaks.
2. Entity mapping a spawned component in scenes incurs unnecessary
overhead: look up ReflectMapEntities, create a _brand new temporary
instance_ of the component using FromReflect, map the entities in that
instance, and then apply that on top of the actual component using
reflection. We can do much better.

Additionally, while our new [Entity cloning
system](https://github.com/bevyengine/bevy/pull/16132) is already pretty
great, it has some areas we can make better:

* It doesn't expose semantic info about the clone (ex: ignore or "clone
empty"), meaning we can't key off of that in places where it would be
useful, such as scene spawning. Rather than duplicating this info across
contexts, I think it makes more sense to add that info to the clone
system, especially given that we'd like to use cloning code in some of
our spawning scenarios.
* EntityCloner is currently built in a way that prioritizes a single
entity clone
* EntityCloner's recursive cloning is built to be done "inside out" in a
parallel context (queue commands that each have a clone of
EntityCloner). By making EntityCloner the orchestrator of the clone we
can remove internal arcs, improve the clarity of the code, make
EntityCloner mutable again, and simplify the builder code.
* EntityCloner does not currently take into account entity mapping. This
is necessary to do true "bullet proof" cloning, would allow us to unify
the per-component scene spawning and cloning UX, and ultimately would
allow us to use EntityCloner in place of raw reflection for scenes like
`Scene(World)` (which would give us a nice performance boost: fewer
archetype moves, less reflection overhead).

## Solution

### Improved Entity Mapping

First, components now have first-class "entity visiting and mapping"
behavior:

```rust
#[derive(Component, Reflect)]
#[reflect(Component)]
struct Inventory {
    size: usize,
    #[entities]
    items: Vec<Entity>,
}
```

Any field with the `#[entities]` annotation will be viewable and
mappable when cloning and spawning scenes.

Compare that to what was required before!

```rust
#[derive(Component, Reflect, VisitEntities, VisitEntitiesMut)]
#[reflect(Component, MapEntities)]
struct Inventory {
    #[visit_entities(ignore)]
    size: usize,
    items: Vec<Entity>,
}
```

Additionally, for relationships `#[entities]` is implied, meaning this
"just works" in scenes and cloning:

```rust
#[derive(Component, Reflect)]
#[relationship(relationship_target = Children)]
#[reflect(Component)]
struct ChildOf(pub Entity);
```

Note that Component _does not_ implement `VisitEntities` directly.
Instead, it has `Component::visit_entities` and
`Component::visit_entities_mut` methods. This is for a few reasons:

1. We cannot implement `VisitEntities for C: Component` because that
would conflict with our impl of VisitEntities for anything that
implements `IntoIterator<Item=Entity>`. Preserving that impl is more
important from a UX perspective.
2. We should not implement `Component: VisitEntities` VisitEntities in
the Component derive, as that would increase the burden of manual
Component trait implementors.
3. Making VisitEntitiesMut directly callable for components would make
it easy to invalidate invariants defined by a component author. By
putting it in the `Component` impl, we can make it harder to call
naturally / unavailable to autocomplete using `fn
visit_entities_mut(this: &mut Self, ...)`.

`ReflectComponent::apply_or_insert` is now
`ReflectComponent::apply_or_insert_mapped`. By moving mapping inside
this impl, we remove the need to go through the reflection system to do
entity mapping, meaning we no longer need to create a clone of the
target component, map the entities in that component, and patch those
values on top. This will make spawning mapped entities _much_ faster
(The default `Component::visit_entities_mut` impl is an inlined empty
function, so it will incur no overhead for unmapped entities).

### The Bug Fix

To solve #17535, spawning code now skips entities with the new
`ComponentCloneBehavior::Ignore` and
`ComponentCloneBehavior::RelationshipTarget` variants (note
RelationshipTarget is a temporary "workaround" variant that allows
scenes to skip these components. This is a temporary workaround that can
be removed as these cases should _really_ be using EntityCloner logic,
which should be done in a followup PR. When that is done,
`ComponentCloneBehavior::RelationshipTarget` can be merged into the
normal `ComponentCloneBehavior::Custom`).

### Improved Cloning

* `Option<ComponentCloneHandler>` has been replaced by
`ComponentCloneBehavior`, which encodes additional intent and context
(ex: `Default`, `Ignore`, `Custom`, `RelationshipTarget` (this last one
is temporary)).
* Global per-world entity cloning configuration has been removed. This
felt overly complicated, increased our API surface, and felt too
generic. Each clone context can have different requirements (ex: what a
user wants in a specific system, what a scene spawner wants, etc). I'd
prefer to see how far context-specific EntityCloners get us first.
* EntityCloner's internals have been reworked to remove Arcs and make it
mutable.
* EntityCloner is now directly stored on EntityClonerBuilder,
simplifying the code somewhat
* EntityCloner's "bundle scratch" pattern has been moved into the new
BundleScratch type, improving its usability and making it usable in
other contexts (such as future cross-world cloning code). Currently this
is still private, but with some higher level safe APIs it could be used
externally for making dynamic bundles
* EntityCloner's recursive cloning behavior has been "externalized". It
is now responsible for orchestrating recursive clones, meaning it no
longer needs to be sharable/clone-able across threads / read-only.
* EntityCloner now does entity mapping during clones, like scenes do.
This gives behavior parity and also makes it more generically useful.
* `RelatonshipTarget::RECURSIVE_SPAWN` is now
`RelationshipTarget::LINKED_SPAWN`, and this field is used when cloning
relationship targets to determine if cloning should happen recursively.
The new `LINKED_SPAWN` term was picked to make it more generically
applicable across spawning and cloning scenarios.

## Next Steps

* I think we should adapt EntityCloner to support cross world cloning. I
think this PR helps set the stage for that by making the internals
slightly more generalized. We could have a CrossWorldEntityCloner that
reuses a lot of this infrastructure.
* Once we support cross world cloning, we should use EntityCloner to
spawn `Scene(World)` scenes. This would yield significant performance
benefits (no archetype moves, less reflection overhead).

---------

Co-authored-by: eugineerd <70062110+eugineerd@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-02-06 22:13:41 +00:00
poopy
15f00278e7
Rename ArgList::push methods to with and add new push methods which take &mut self (#16567)
# Objective

The `ArgList::push` family of methods consume `self` and return a new
`ArgList` which means they can't be used with `&mut ArgList` references.

```rust
fn foo(args: &mut ArgList) {
    args.push_owned(47_i32); // doesn't work :(
}
```

It's typical for `push` methods on other existing types to take `&mut
self`.

## Solution

Renamed the existing push methods to `with_arg`, `with_ref` etc and
added new `push` methods which take `&mut self`.

## Migration Guide

Uses of the `ArgList::push` methods should be replaced with the `with`
counterpart.

<details>

| old | new |
| --- | --- |
| push_arg | with_arg |
| push_ref | with_ref |
| push_mut | with_mut |
| push_owned | with_owned | 
| push_boxed | with_boxed |

</details>
2025-01-28 05:06:50 +00:00
Zachary Harrold
9bc0ae33c3
Move hashbrown and foldhash out of bevy_utils (#17460)
# Objective

- Contributes to #16877

## Solution

- Moved `hashbrown`, `foldhash`, and related types out of `bevy_utils`
and into `bevy_platform_support`
- Refactored the above to match the layout of these types in `std`.
- Updated crates as required.

## Testing

- CI

---

## Migration Guide

- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::hash`:
  - `FixedState`
  - `DefaultHasher`
  - `RandomState`
  - `FixedHasher`
  - `Hashed`
  - `PassHash`
  - `PassHasher`
  - `NoOpHash`
- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::collections`:
  - `HashMap`
  - `HashSet`
- `bevy_utils::hashbrown` has been removed. Instead, import from
`bevy_platform_support::collections` _or_ take a dependency on
`hashbrown` directly.
- `bevy_utils::Entry` has been removed. Instead, import from
`bevy_platform_support::collections::hash_map` or
`bevy_platform_support::collections::hash_set` as appropriate.
- All of the above equally apply to `bevy::utils` and
`bevy::platform_support`.

## Notes

- I left `PreHashMap`, `PreHashMapExt`, and `TypeIdMap` in `bevy_utils`
as they might be candidates for micro-crating. They can always be moved
into `bevy_platform_support` at a later date if desired.
2025-01-23 16:46:08 +00:00
Carter Anderson
ba5e71f53d
Parent -> ChildOf (#17427)
Fixes #17412

## Objective

`Parent` uses the "has a X" naming convention. There is increasing
sentiment that we should use the "is a X" naming convention for
relationships (following #17398). This leaves `Children` as-is because
there is prevailing sentiment that `Children` is clearer than `ParentOf`
in many cases (especially when treating it like a collection).

This renames `Parent` to `ChildOf`.

This is just the implementation PR. To discuss the path forward, do so
in #17412.

## Migration Guide

- The `Parent` component has been renamed to `ChildOf`.
2025-01-20 22:13:29 +00:00
Alice Cecile
5a9bc28502
Support non-Vec data structures in relations (#17447)
# Objective

The existing `RelationshipSourceCollection` uses `Vec` as the only
possible backing for our relationships. While a reasonable choice,
benchmarking use cases might reveal that a different data type is better
or faster.

For example:

- Not all relationships require a stable ordering between the
relationship sources (i.e. children). In cases where we a) have many
such relations and b) don't care about the ordering between them, a hash
set is likely a better datastructure than a `Vec`.
- The number of children-like entities may be small on average, and a
`smallvec` may be faster

## Solution

- Implement `RelationshipSourceCollection` for `EntityHashSet`, our
custom entity-optimized `HashSet`.
-~~Implement `DoubleEndedIterator` for `EntityHashSet` to make things
compile.~~
   -  This implementation was cursed and very surprising.
- Instead, by moving the iterator type on `RelationshipSourceCollection`
from an erased RPTIT to an explicit associated type we can add a trait
bound on the offending methods!
- Implement `RelationshipSourceCollection` for `SmallVec`

## Testing

I've added a pair of new tests to make sure this pattern compiles
successfully in practice!

## Migration Guide

`EntityHashSet` and `EntityHashMap` are no longer re-exported in
`bevy_ecs::entity` directly. If you were not using `bevy_ecs` / `bevy`'s
`prelude`, you can access them through their now-public modules,
`hash_set` and `hash_map` instead.

## Notes to reviewers

The `EntityHashSet::Iter` type needs to be public for this impl to be
allowed. I initially renamed it to something that wasn't ambiguous and
re-exported it, but as @Victoronz pointed out, that was somewhat
unidiomatic.

In
1a8564898f,
I instead made the `entity_hash_set` public (and its `entity_hash_set`)
sister public, and removed the re-export. I prefer this design (give me
module docs please), but it leads to a lot of churn in this PR.

Let me know which you'd prefer, and if you'd like me to split that
change out into its own micro PR.
2025-01-20 21:26:08 +00:00
Carter Anderson
21f1e3045c
Relationships (non-fragmenting, one-to-many) (#17398)
This adds support for one-to-many non-fragmenting relationships (with
planned paths for fragmenting and non-fragmenting many-to-many
relationships). "Non-fragmenting" means that entities with the same
relationship type, but different relationship targets, are not forced
into separate tables (which would cause "table fragmentation").

Functionally, this fills a similar niche as the current Parent/Children
system. The biggest differences are:

1. Relationships have simpler internals and significantly improved
performance and UX. Commands and specialized APIs are no longer
necessary to keep everything in sync. Just spawn entities with the
relationship components you want and everything "just works".
2. Relationships are generalized. Bevy can provide additional built in
relationships, and users can define their own.

**REQUEST TO REVIEWERS**: _please don't leave top level comments and
instead comment on specific lines of code. That way we can take
advantage of threaded discussions. Also dont leave comments simply
pointing out CI failures as I can read those just fine._

## Built on top of what we have

Relationships are implemented on top of the Bevy ECS features we already
have: components, immutability, and hooks. This makes them immediately
compatible with all of our existing (and future) APIs for querying,
spawning, removing, scenes, reflection, etc. The fewer specialized APIs
we need to build, maintain, and teach, the better.

## Why focus on one-to-many non-fragmenting first?

1. This allows us to improve Parent/Children relationships immediately,
in a way that is reasonably uncontroversial. Switching our hierarchy to
fragmenting relationships would have significant performance
implications. ~~Flecs is heavily considering a switch to non-fragmenting
relations after careful considerations of the performance tradeoffs.~~
_(Correction from @SanderMertens: Flecs is implementing non-fragmenting
storage specialized for asset hierarchies, where asset hierarchies are
many instances of small trees that have a well defined structure)_
2. Adding generalized one-to-many relationships is currently a priority
for the [Next Generation Scene / UI
effort](https://github.com/bevyengine/bevy/discussions/14437).
Specifically, we're interested in building reactions and observers on
top.

## The changes

This PR does the following:

1. Adds a generic one-to-many Relationship system
3. Ports the existing Parent/Children system to Relationships, which now
lives in `bevy_ecs::hierarchy`. The old `bevy_hierarchy` crate has been
removed.
4. Adds on_despawn component hooks
5. Relationships can opt-in to "despawn descendants" behavior, meaning
that the entire relationship hierarchy is despawned when
`entity.despawn()` is called. The built in Parent/Children hierarchies
enable this behavior, and `entity.despawn_recursive()` has been removed.
6. `world.spawn` now applies commands after spawning. This ensures that
relationship bookkeeping happens immediately and removes the need to
manually flush. This is in line with the equivalent behaviors recently
added to the other APIs (ex: insert).
7. Removes the ValidParentCheckPlugin (system-driven / poll based) in
favor of a `validate_parent_has_component` hook.

## Using Relationships

The `Relationship` trait looks like this:

```rust
pub trait Relationship: Component + Sized {
    type RelationshipSources: RelationshipSources<Relationship = Self>;
    fn get(&self) -> Entity;
    fn from(entity: Entity) -> Self;
}
```

A relationship is a component that:

1. Is a simple wrapper over a "target" Entity.
2. Has a corresponding `RelationshipSources` component, which is a
simple wrapper over a collection of entities. Every "target entity"
targeted by a "source entity" with a `Relationship` has a
`RelationshipSources` component, which contains every "source entity"
that targets it.

For example, the `Parent` component (as it currently exists in Bevy) is
the `Relationship` component and the entity containing the Parent is the
"source entity". The entity _inside_ the `Parent(Entity)` component is
the "target entity". And that target entity has a `Children` component
(which implements `RelationshipSources`).

In practice, the Parent/Children relationship looks like this:

```rust
#[derive(Relationship)]
#[relationship(relationship_sources = Children)]
pub struct Parent(pub Entity);

#[derive(RelationshipSources)]
#[relationship_sources(relationship = Parent)]
pub struct Children(Vec<Entity>);
```

The Relationship and RelationshipSources derives automatically implement
Component with the relevant configuration (namely, the hooks necessary
to keep everything in sync).

The most direct way to add relationships is to spawn entities with
relationship components:

```rust
let a = world.spawn_empty().id();
let b = world.spawn(Parent(a)).id();

assert_eq!(world.entity(a).get::<Children>().unwrap(), &[b]);
```

There are also convenience APIs for spawning more than one entity with
the same relationship:

```rust
world.spawn_empty().with_related::<Children>(|s| {
    s.spawn_empty();
    s.spawn_empty();
})
```

The existing `with_children` API is now a simpler wrapper over
`with_related`. This makes this change largely non-breaking for existing
spawn patterns.

```rust
world.spawn_empty().with_children(|s| {
    s.spawn_empty();
    s.spawn_empty();
})
```

There are also other relationship APIs, such as `add_related` and
`despawn_related`.

## Automatic recursive despawn via the new on_despawn hook

`RelationshipSources` can opt-in to "despawn descendants" behavior,
which will despawn all related entities in the relationship hierarchy:

```rust
#[derive(RelationshipSources)]
#[relationship_sources(relationship = Parent, despawn_descendants)]
pub struct Children(Vec<Entity>);
```

This means that `entity.despawn_recursive()` is no longer required.
Instead, just use `entity.despawn()` and the relevant related entities
will also be despawned.

To despawn an entity _without_ despawning its parent/child descendants,
you should remove the `Children` component first, which will also remove
the related `Parent` components:

```rust
entity
    .remove::<Children>()
    .despawn()
```

This builds on the on_despawn hook introduced in this PR, which is fired
when an entity is despawned (before other hooks).

## Relationships are the source of truth

`Relationship` is the _single_ source of truth component.
`RelationshipSources` is merely a reflection of what all the
`Relationship` components say. By embracing this, we are able to
significantly improve the performance of the system as a whole. We can
rely on component lifecycles to protect us against duplicates, rather
than needing to scan at runtime to ensure entities don't already exist
(which results in quadratic runtime). A single source of truth gives us
constant-time inserts. This does mean that we cannot directly spawn
populated `Children` components (or directly add or remove entities from
those components). I personally think this is a worthwhile tradeoff,
both because it makes the performance much better _and_ because it means
theres exactly one way to do things (which is a philosophy we try to
employ for Bevy APIs).

As an aside: treating both sides of the relationship as "equivalent
source of truth relations" does enable building simple and flexible
many-to-many relationships. But this introduces an _inherent_ need to
scan (or hash) to protect against duplicates.
[`evergreen_relations`](https://github.com/EvergreenNest/evergreen_relations)
has a very nice implementation of the "symmetrical many-to-many"
approach. Unfortunately I think the performance issues inherent to that
approach make it a poor choice for Bevy's default relationship system.

## Followup Work

* Discuss renaming `Parent` to `ChildOf`. I refrained from doing that in
this PR to keep the diff reasonable, but I'm personally biased toward
this change (and using that naming pattern generally for relationships).
* [Improved spawning
ergonomics](https://github.com/bevyengine/bevy/discussions/16920)
* Consider adding relationship observers/triggers for "relationship
targets" whenever a source is added or removed. This would replace the
current "hierarchy events" system, which is unused upstream but may have
existing users downstream. I think triggers are the better fit for this
than a buffered event queue, and would prefer not to add that back.
* Fragmenting relations: My current idea hinges on the introduction of
"value components" (aka: components whose type _and_ value determines
their ComponentId, via something like Hashing / PartialEq). By labeling
a Relationship component such as `ChildOf(Entity)` as a "value
component", `ChildOf(e1)` and `ChildOf(e2)` would be considered
"different components". This makes the transition between fragmenting
and non-fragmenting a single flag, and everything else continues to work
as expected.
* Many-to-many support
* Non-fragmenting: We can expand Relationship to be a list of entities
instead of a single entity. I have largely already written the code for
this.
* Fragmenting: With the "value component" impl mentioned above, we get
many-to-many support "for free", as it would allow inserting multiple
copies of a Relationship component with different target entities.

Fixes #3742 (If this PR is merged, I think we should open more targeted
followup issues for the work above, with a fresh tracking issue free of
the large amount of less-directed historical context)
Fixes #17301
Fixes #12235 
Fixes #15299
Fixes #15308 

## Migration Guide

* Replace `ChildBuilder` with `ChildSpawnerCommands`.
* Replace calls to `.set_parent(parent_id)` with
`.insert(Parent(parent_id))`.
* Replace calls to `.replace_children()` with `.remove::<Children>()`
followed by `.add_children()`. Note that you'll need to manually despawn
any children that are not carried over.
* Replace calls to `.despawn_recursive()` with `.despawn()`.
* Replace calls to `.despawn_descendants()` with
`.despawn_related::<Children>()`.
* If you have any calls to `.despawn()` which depend on the children
being preserved, you'll need to remove the `Children` component first.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-01-18 22:20:30 +00:00
MichiRecRoom
26bb0b40d2
Move #![warn(clippy::allow_attributes, clippy::allow_attributes_without_reason)] to the workspace Cargo.toml (#17374)
# Objective
Fixes https://github.com/bevyengine/bevy/issues/17111

## Solution
Move `#![warn(clippy::allow_attributes,
clippy::allow_attributes_without_reason)]` to the workspace `Cargo.toml`

## Testing
Lots of CI testing, and local testing too.

---------

Co-authored-by: Benjamin Brienen <benjamin.brienen@outlook.com>
2025-01-15 01:14:58 +00:00
Carter Anderson
4bca7f1b6d
Improved Command Errors (#17215)
# Objective

Rework / build on #17043 to simplify the implementation. #17043 should
be merged first, and the diff from this PR will get much nicer after it
is merged (this PR is net negative LOC).

## Solution

1. Command and EntityCommand have been vastly simplified. No more marker
components. Just one function.
2. Command and EntityCommand are now generic on the return type. This
enables result-less commands to exist, and allows us to statically
distinguish between fallible and infallible commands, which allows us to
skip the "error handling overhead" for cases that don't need it.
3. There are now only two command queue variants: `queue` and
`queue_fallible`. `queue` accepts commands with no return type.
`queue_fallible` accepts commands that return a Result (specifically,
one that returns an error that can convert to
`bevy_ecs::result::Error`).
4. I've added the concept of the "default error handler", which is used
by `queue_fallible`. This is a simple direct call to the `panic()` error
handler by default. Users that want to override this can enable the
`configurable_error_handler` cargo feature, then initialize the
GLOBAL_ERROR_HANDLER value on startup. This is behind a flag because
there might be minor overhead with `OnceLock` and I'm guessing this will
be a niche feature. We can also do perf testing with OnceLock if someone
really wants it to be used unconditionally, but I don't personally feel
the need to do that.
5. I removed the "temporary error handler" on Commands (and all code
associated with it). It added more branching, made Commands bigger /
more expensive to initialize (note that we construct it at high
frequencies / treat it like a pointer type), made the code harder to
follow, and introduced a bunch of additional functions. We instead rely
on the new default error handler used in `queue_fallible` for most
things. In the event that a custom handler is required,
`handle_error_with` can be used.
6. EntityCommand now _only_ supports functions that take
`EntityWorldMut` (and all existing entity commands have been ported).
Removing the marker component from EntityCommand hinged on this change,
but I strongly believe this is for the best anyway, as this sets the
stage for more efficient batched entity commands.
7. I added `EntityWorldMut::resource` and the other variants for more
ergonomic resource access on `EntityWorldMut` (removes the need for
entity.world_scope, which also incurs entity-lookup overhead).

## Open Questions

1. I believe we could merge `queue` and `queue_fallible` into a single
`queue` which accepts both fallible and infallible commands (via the
introduction of a `QueueCommand` trait). Is this desirable?
2025-01-10 04:15:50 +00:00
MichiRecRoom
3742e621ef
Allow clippy::too_many_arguments to lint without warnings (#17249)
# Objective
Many instances of `clippy::too_many_arguments` linting happen to be on
systems - functions which we don't call manually, and thus there's not
much reason to worry about the argument count.

## Solution
Allow `clippy::too_many_arguments` globally, and remove all lint
attributes related to it.
2025-01-09 07:26:15 +00:00
MichiRecRoom
8e51b326b5
Cleanup instances of #[allow(clippy::type_complexity)] (#17248)
# Objective
I never realized `clippy::type_complexity` was an allowed lint - I've
been assuming it'd generate a warning when performing my linting PRs.

## Solution
Removes any instances of `#[allow(clippy::type_complexity)]` and
`#[expect(clippy::type_complexity)]`

## Testing
`cargo clippy` ran without errors or warnings.
2025-01-09 06:25:20 +00:00
BD103
020d082617
Fix "Unrecognized Option" error when using Criterion-specific arguments in benchmarks (#17222)
# Objective

- Commands like `cargo bench -- --save-baseline before` do not work
because the default `libtest` is intercepting Criterion-specific CLI
arguments.
- Fixes #17200.

## Solution

- Disable the default `libtest` benchmark harness for the library crate,
as per [the Criterion
book](https://bheisler.github.io/criterion.rs/book/faq.html#cargo-bench-gives-unrecognized-option-errors-for-valid-command-line-options).

## Testing

- `cargo bench -p benches -- --save-baseline before`
- You don't need to run the entire benchmarks, just make sure that they
start without any errors. :)
2025-01-08 00:09:31 +00:00
JaySpruce
ee4414159b
Add Result handling to Commands and EntityCommands (#17043)
## Objective

Fixes #2004
Fixes #3845
Fixes #7118
Fixes #10166

## Solution

- The crux of this PR is the new `Command::with_error_handling` method.
This wraps the relevant command in another command that, when applied,
will apply the original command and handle any resulting errors.
- To enable this, `Command::apply` and `EntityCommand::apply` now return
`Result`.
- `Command::with_error_handling` takes as a parameter an error handler
of the form `fn(&mut World, CommandError)`, which it passes the error
to.
- `CommandError` is an enum that can be either `NoSuchEntity(Entity)` or
`CommandFailed(Box<dyn Error>)`.

### Closures
- Closure commands can now optionally return `Result`, which will be
passed to `with_error_handling`.

### Commands
- Fallible commands can be queued with `Commands::queue_fallible` and
`Commands::queue_fallible_with`, which call `with_error_handling` before
queuing them (using `Commands::queue` will queue them without error
handling).
- `Commands::queue_fallible_with` takes an `error_handler` parameter,
which will be used by `with_error_handling` instead of a command's
default.
- The `command` submodule provides unqueued forms of built-in fallible
commands so that you can use them with `queue_fallible_with`.
- There is also an `error_handler` submodule that provides simple error
handlers for convenience.

### Entity Commands
- `EntityCommand` now automatically checks if the entity exists before
executing the command, and returns `NoSuchEntity` if it doesn't.
- Since all entity commands might need to return an error, they are
always queued with error handling.
- `EntityCommands::queue_with` takes an `error_handler` parameter, which
will be used by `with_error_handling` instead of a command's default.
- The `entity_command` submodule provides unqueued forms of built-in
entity commands so that you can use them with `queue_with`.

### Defaults
- In the future, commands should all fail according to the global error
handling setting. That doesn't exist yet though.
- For this PR, commands all fail the way they do on `main`.
- Both now and in the future, the defaults can be overridden by
`Commands::override_error_handler` (or equivalent methods on
`EntityCommands` and `EntityEntryCommands`).
- `override_error_handler` takes an error handler (`fn(&mut World,
CommandError)`) and passes it to every subsequent command queued with
`Commands::queue_fallible` or `EntityCommands::queue`.
- The `_with` variants of the queue methods will still provide an error
handler directly to the command.
- An override can be reset with `reset_error_handler`.

## Future Work

- After a universal error handling mode is added, we can change all
commands to fail that way by default.
- Once we have all commands failing the same way (which would require
either the full removal of `try` variants or just making them useless
while they're deprecated), `queue_fallible_with_default` could be
removed, since its only purpose is to enable commands having different
defaults.
2025-01-07 16:50:52 +00:00
BD103
765166b727
Update entity cloning benchmarks (#17084)
# Objective

- `entity_cloning` was separated from the rest of the ECS benchmarks.
- There was some room for improvement in the benchmarks themselves.
- Part of #16647.

## Solution

- Merge `entity_cloning` into the rest of the ECS benchmarks.
- Apply the `bench!` macro to all benchmark names.\
- Reorganize benchmarks and their helper functions, with more comments
than before.
- Remove all the extra component definitions (`C2`, `C3`, etc.), and
just leave one. Now all entities have exactly one component.

## Testing

```sh
# List all entity cloning benchmarks, to verify their names have updated.
cargo bench -p benches --bench ecs entity_cloning -- --list

# Test benchmarks by running them once.
cargo test -p benches --bench ecs entity_cloning

# Run all benchmarks (takes about a minute).
cargo bench -p benches --bench ecs entity_cloning
```

---

## Showcase


![image](https://github.com/user-attachments/assets/4e3d7d98-015a-4974-ae16-363cf1b9423c)

Interestingly, using `Clone` instead of `Reflect` appears to be 2-2.5
times faster. Furthermore, there were noticeable jumps in time when
running the benchmarks:


![image](https://github.com/user-attachments/assets/bd8513de-3922-432f-b3dd-1b1b7750bdb5)


I theorize this is because the `World` is allocating more space for all
the entities, but I don't know for certain. Neat!
2025-01-02 19:55:35 +00:00
BD103
c890cc9dc3
Overhaul picking benchmarks (#17033)
# Objective

- Part of #16647.
- This PR goes through our `ray_cast::ray_mesh_intersection()`
benchmarks and overhauls them with more comments and better
extensibility. The code is also a lot less duplicated!

## Solution

- Create a `Benchmarks` enum that describes all of the different kind of
scenarios we want to benchmark.
- Merge all of our existing benchmark functions into a single one,
`bench()`, which sets up the scenarios all at once.
- Add comments to `mesh_creation()` and `ptoxznorm()`, and move some
lines around to be a bit clearer.
- Make the benchmarks use the new `bench!` macro, as part of #16647.
- Rename many functions and benchmarks to be clearer.

## For reviewers

I split this PR up into several, easier to digest commits. You might
find it easier to review by looking through each commit, instead of the
complete file changes.

None of my changes actually modifies the behavior of the benchmarks;
they still track the exact same test cases. There shouldn't be
significant changes in benchmark performance before and after this PR.

## Testing

List all picking benchmarks: `cargo bench -p benches --bench picking --
--list`

Run the benchmarks once in debug mode: `cargo test -p benches --bench
picking`

Run the benchmarks and analyze their performance: `cargo bench -p
benches --bench picking`

- Check out the generated HTML report in
`./target/criterion/report/index.html` once you're done!

---

## Showcase

List of all picking benchmarks, after having been renamed:

<img width="524" alt="image"
src="https://github.com/user-attachments/assets/a1b53daf-4a8b-4c45-a25a-c6306c7175d1"
/>

Example report for
`picking::ray_mesh_intersection::cull_intersect/100_vertices`:

<img width="992" alt="image"
src="https://github.com/user-attachments/assets/a1aaf53f-ce21-4bef-89c4-b982bb158f5d"
/>
2024-12-30 21:04:24 +00:00
BD103
291cb31798
Overhaul bezier curve benchmarks (#17016)
# Objective

- Part of #16647.
- The benchmarks for bezier curves have several issues and do not yet
use the new `bench!` naming scheme.

## Solution

- Make all `bevy_math` benchmarks use the `bench!` macro for their name.
- Delete the `build_accel_cubic()` benchmark, since it was an exact
duplicate of `build_pos_cubic()`.
- Remove `collect::<Vec<_>>()` call in `build_pos_cubic()` and replace
it with a `for` loop.
- Combine all of the benchmarks that measure `curve.position()` under a
single group, `curve_position`, and extract the common bench routine
into a helper function.
- Move the time calculation for the `curve.ease()` benchmark into the
setup closure so it is not tracked.
- Rename the benchmarks to be more descriptive on what they do.
  - `easing_1000` -> `segment_ease`
  - `cubic_position_Vec2` -> `curve_position/vec2`
  - `cubic_position_Vec3A` -> `curve_position/vec3a`
  - `cubic_position_Vec3` -> `curve_position/vec3`
  - `build_pos_cubic_100_points` -> `curve_iter_positions`

## Testing

- `cargo test -p benches --bench math`
- `cargo bench -p benches --bench math`
  - Then open `./target/criterion/report/index.html` to see the report!

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-12-29 20:55:08 +00:00
BD103
17ad855653
Migrate to core::hint::black_box() (#16980)
# Objective

Many of our benchmarks use
[`criterion::black_box()`](https://docs.rs/criterion/latest/criterion/fn.black_box.html),
which is used to prevent the compiler from optimizing away computation
that we're trying to time. This can be slow, though, because
`criterion::black_box()` forces a point read each time it is called
through
[`ptr::road_volatile()`](https://doc.rust-lang.org/stable/std/ptr/fn.read_volatile.html).

In Rust 1.66, the standard library introduced
[`core::hint::black_box()`](https://doc.rust-lang.org/nightly/std/hint/fn.black_box.html)
(and `std::hint::black_box()`). This is an intended replacement for
`criterion`'s version that uses compiler intrinsics instead of volatile
pointer reads, and thus has no runtime overhead. This increases
benchmark accuracy, which is always nice 👍

Note that benchmarks may _appear_ to improve in performance after this
change, but that's just because we are eliminating the pointer read
overhead.

## Solution

- Deny `criterion::black_box` in `clippy.toml`.
- Fix all imports.

## Testing

- `cargo clippy -p benches --benches`
2024-12-29 19:33:42 +00:00
BD103
f391522483
Test benchmarks in CI (#16987)
# Objective

- This reverts #16833, and completely goes against #16803.
- Turns out running `cargo test --benches` runs each benchmark once,
without timing it, just to ensure nothing panics. This is actually
desired because we can use it to verify benchmarks are working correctly
without all the time constraints of actual benchmarks.

## Solution

- Add the `--benches` flag to the CI test command.

## Testing

- `cargo run -p ci -- test`
2024-12-29 19:33:06 +00:00
BD103
c03e494a26
Migrate reflection benchmarks to new naming system (#16986)
# Objective

- Please see #16647 for the full reasoning behind this change.

## Solution

- Create the `bench!` macro, which generates the name of the benchmark
at compile time.

Migrating is a single line change, and it will automatically update if
you move the benchmark to a different module:

  ```diff
  + use benches::bench;

  fn my_benchmark(c: &mut Criterion) {
  -   c.bench_function("my_benchmark", |b| {});
  +   c.bench_function(bench!("my_benchmark"), |b| {});
  }
  ```

- Migrate all reflection benchmarks to use `bench!`.
- Fix a few places where `black_box()` or Criterion is misused.

## Testing

```sh
cd benches

# Will take a long time!
cargo bench --bench reflect

# List out the names of all reflection benchmarks, to ensure I didn't miss anything.
cargo bench --bench reflect -- --list

# Check for linter warnings.
cargo clippy --bench reflect

# Run each benchmark once.
cargo test --bench reflect
```
2024-12-26 22:28:09 +00:00
Oliver Maskery
a7ae0807ac
Fix panic in benches caused by missing resources (#16956)
# Objective

- To fix the benches panicking on `main`

## Solution

- It appears that systems requiring access to a non-existing `Res` now
causes a panic
- Some of the benches run systems that access resources that have not
been inserted into the world
- I have made it so that those resources are inserted into the world

## Testing

- I ran all the ecs benches and they all run without panicking

Co-authored-by: Oliver Maskery <oliver@wellplayed.games>
2024-12-24 17:18:03 +00:00
BD103
20277006ce
Add benchmarks and compile_fail tests back to workspace (#16858)
# Objective

- Our benchmarks and `compile_fail` tests lag behind the rest of the
engine because they are not in the Cargo workspace, so not checked by
CI.
- Fixes #16801, please see it for further context!

## Solution

- Add benchmarks and `compile_fail` tests to the Cargo workspace.
- Fix any leftover formatting issues and documentation.

## Testing

- I think CI should catch most things!

## Questions

<details>
<summary>Outdated issue I was having with function reflection being
optional</summary>

The `reflection_types` example is failing in Rust-Analyzer for me, but
not a normal check.

```rust
error[E0004]: non-exhaustive patterns: `ReflectRef::Function(_)` not covered
   --> examples/reflection/reflection_types.rs:81:11
    |
81  |     match value.reflect_ref() {
    |           ^^^^^^^^^^^^^^^^^^^ pattern `ReflectRef::Function(_)` not covered
    |
note: `ReflectRef<'_>` defined here
   --> /Users/bdeep/dev/bevy/bevy/crates/bevy_reflect/src/kind.rs:178:1
    |
178 | pub enum ReflectRef<'a> {
    | ^^^^^^^^^^^^^^^^^^^^^^^
...
188 |     Function(&'a dyn Function),
    |     -------- not covered
    = note: the matched value is of type `ReflectRef<'_>`
help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
    |
126 ~         ReflectRef::Opaque(_) => {},
127 +         ReflectRef::Function(_) => todo!()
    |
```

I think it is because the following line is feature-gated:


cc0f6a8db4/examples/reflection/reflection_types.rs (L117-L122)

My theory for why this is happening is because the benchmarks enabled
`bevy_reflect`'s `function` feature, which gets merged with the rest of
the features when RA checks the workspace, but the `#[cfg(...)]` gate in
the example isn't detecting it:


cc0f6a8db4/benches/Cargo.toml (L19)

Any thoughts on how to fix this? It's not blocking, since the example
still compiles as normal, but it's just RA and the command `cargo check
--workspace --all-targets` appears to fail.

</summary>
2024-12-21 22:30:29 +00:00
eugineerd
20049d4c34
Faster entity cloning (#16717)
# Objective

#16132 introduced entity cloning functionality, and while it works and
is useful, it can be made faster. This is the promised follow-up to
improve performance.

## Solution

**PREFACE**: This is my first time writing `unsafe` in rust and I have
only vague idea about what I'm doing. I would encourage reviewers to
scrutinize `unsafe` parts in particular.

The solution is to clone component data to an intermediate buffer and
use `EntityWorldMut::insert_by_ids` to insert components without
additional archetype moves.

To facilitate this, `EntityCloner::clone_entity` now reads all
components of the source entity and provides clone handlers with the
ability to read component data straight from component storage using
`read_source_component` and write to an intermediate buffer using
`write_target_component`. `ComponentId` is used to check that requested
type corresponds to the type available on source entity.

Reflect-based handler is a little trickier to pull of: we only have
`&dyn Reflect` and no direct access to the underlying data.
`ReflectFromPtr` can be used to get `&dyn Reflect` from concrete
component data, but to write it we need to create a clone of the
underlying data using `Reflect`. For this reason only components that
have `ReflectDefault` or `ReflectFromReflect` or `ReflectFromWorld` can
be cloned, all other components will be skipped. The good news is that
this is actually only a temporary limitation: once #13432 lands we will
be able to clone component without requiring one of these `type data`s.

This PR also introduces `entity_cloning` benchmark to better compare
changes between the PR and main, you can see the results in the
**showcase** section.

## Testing

- All previous tests passing
- Added test for fast reflect clone path (temporary, will be removed
after reflection-based cloning lands)
- Ran miri

## Showcase
Here's a table demonstrating the improvement:

| **benchmark** | **main, avg** | **PR, avg** | **change, avg** |
| ----------------------- | ------------- | ----------- |
--------------- |
| many components reflect | 18.505 µs | 2.1351 µs | -89.095% |
| hierarchy wide reflect* | 22.778 ms | 4.1875 ms | -81.616% |
| hierarchy tall reflect* | 107.24 µs | 26.322 µs | -77.141% |
| hierarchy many reflect | 78.533 ms | 9.7415 ms | -87.596% |
| many components clone | 1.3633 µs | 758.17 ns | -45.937% |
| hierarchy wide clone* | 2.7716 ms | 3.3411 ms | +20.546% |
| hierarchy tall clone* | 17.646 µs | 20.190 µs | +17.379% |
| hierarchy many clone | 5.8779 ms | 4.2650 ms | -27.439% |

*: these benchmarks have entities with only 1 component

## Considerations
Once #10154 is resolved a large part of the functionality in this PR
will probably become obsolete. It might still be a little bit faster
than using command batching, but the complexity might not be worth it.

## Migration Guide
- `&EntityCloner` in component clone handlers is changed to `&mut
ComponentCloneCtx` to better separate data.
- Changed `EntityCloneHandler` from enum to struct and added convenience
functions to add default clone and reflect handler more easily.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Chris Russell <8494645+chescock@users.noreply.github.com>
2024-12-18 20:03:39 +00:00
BD103
6178ce93e8
Fix Clippy lints in benchmarks (#16808)
# Objective

- Closes #16804.
- This copies over our lint configuration to our benchmarks and fixes
any lints.

## Solution

- Copied over our Clippy configuration from the root `Cargo.toml` to
`benches/Cargo.toml`.
- Fixed any warnings that Clippy emitted.

## Testing

- `cd benches && cargo clippy --benches`
2024-12-14 05:53:17 +00:00
BD103
c4a24d5b51
Make benchmark setup consistent (#16733)
# Objective

- Benchmarks are inconsistently setup, there are several that do not
compile, and several others that need to be reformatted.
- Related / precursor to #16647, this is part of my attempt migrating
[`bevy-bencher`](https://github.com/TheBevyFlock/bevy-bencher) to the
official benchmarks.

## Solution

> [!TIP]
>
> I recommend reviewing this PR commit-by-commit, instead of all at
once!

In 5d26f56eb9 I reorganized how benches
were registered. Now this is one `[[bench]]` per Bevy crate. In each
crate benchmark folder, there is a `main.rs` that calls
`criterion_main!`. I also disabled automatic benchmark discovery, which
isn't necessarily required, but may clear up confusion with our custom
setup. I also fixed a few errors that were causing the benchmarks to
fail to compile.

In afc8d33a87 I ran `rustfmt` on all of
the benchmarks.

In d6cdf960ab I fixed all of the Clippy
warnings.

In ee94d48f50 I fixed some of the
benchmarks' usage of `black_box()`. I ended up opening
https://github.com/rust-lang/rust/pull/133942 due to this, which should
help prevent this in the future.

In cbe1688dcd I renamed all of the ECS
benchmark groups to be called `benches`, to be consistent with the other
crate benchmarks.

In e701c212cd and
8815bb78b0 I re-ordered some imports and
module definitions, and uplifted `fragmentation/mod.rs` to
`fragementation.rs`.

Finally, in b0065e0b0b I organized
`Cargo.toml` and bumped Criterion to v0.5.

## Testing

- `cd benches && cargo clippy --benches`
- `cd benches && cargo fmt --all`
2024-12-10 20:39:14 +00:00
Gino Valente
d21c7a1911
bevy_reflect: Function Overloading (Generic & Variadic Functions) (#15074)
# Objective

Currently function reflection requires users to manually monomorphize
their generic functions. For example:

```rust
fn add<T: Add<Output=T>>(a: T, b: T) -> T {
    a + b
}

// We have to specify the type of `T`:
let reflect_add = add::<i32>.into_function();
```

This PR doesn't aim to solve that problem—this is just a limitation in
Rust. However, it also means that reflected functions can only ever work
for a single monomorphization. If we wanted to support other types for
`T`, we'd have to create a separate function for each one:

```rust
let reflect_add_i32 = add::<i32>.into_function();
let reflect_add_u32 = add::<u32>.into_function();
let reflect_add_f32 = add::<f32>.into_function();
// ...
```

So in addition to requiring manual monomorphization, we also lose the
benefit of having a single function handle multiple argument types.

If a user wanted to create a small modding script that utilized function
reflection, they'd have to either:
- Store all sets of supported monomorphizations and require users to
call the correct one
- Write out some logic to find the correct function based on the given
arguments

While the first option would work, it wouldn't be very ergonomic. The
second option is better, but it adds additional complexity to the user's
logic—complexity that `bevy_reflect` could instead take on.

## Solution

Introduce [function
overloading](https://en.wikipedia.org/wiki/Function_overloading).

A `DynamicFunction` can now be overloaded with other `DynamicFunction`s.
We can rewrite the above code like so:

```rust
let reflect_add = add::<i32>
    .into_function()
    .with_overload(add::<u32>)
    .with_overload(add::<f32>);
```

When invoked, the `DynamicFunction` will attempt to find a matching
overload for the given set of arguments.

And while I went into this PR only looking to improve generic function
reflection, I accidentally added support for variadic functions as well
(hence why I use the broader term "overload" over "generic").

```rust
// Supports 1 to 4 arguments
let multiply_all = (|a: i32| a)
    .into_function()
    .with_overload(|a: i32, b: i32| a * b)
    .with_overload(|a: i32, b: i32, c: i32| a * b * c)
    .with_overload(|a: i32, b: i32, c: i32, d: i32| a * b * c * d);
```

This is simply an added bonus to this particular implementation. ~~Full
variadic support (i.e. allowing for an indefinite number of arguments)
will be added in a later PR.~~ I actually decided to limit the maximum
number of arguments to 63 to supplement faster lookups, a reduced memory
footprint, and faster cloning.

### Alternatives & Rationale

I explored a few options for handling generic functions. This PR is the
one I feel the most confident in, but I feel I should mention the others
and why I ultimately didn't move forward with them.

#### Adding `GenericDynamicFunction`

**TL;DR:** Adding a distinct `GenericDynamicFunction` type unnecessarily
splits and complicates the API.

<details>
<summary>Details</summary>

My initial explorations involved a dedicated `GenericDynamicFunction` to
contain and handle the mappings.

This was initially started back when `DynamicFunction` was distinct from
`DynamicClosure`. My goal was to not prevent us from being able to
somehow make `DynamicFunction` implement `Copy`. But once we reverted
back to a single `DynamicFunction`, that became a non-issue.

But that aside, the real problem was that it created a split in the API.
If I'm using a third-party library that uses function reflection, I have
to know whether to request a `DynamicFunction` or a
`GenericDynamicFunction`. I might not even know ahead of time which one
I want. It might need to be determined at runtime.

And if I'm creating a library, I might want a type to contain both
`DynamicFunction` and `GenericDynamicFunction`. This might not be
possible if, for example, I need to store the function in a `HashMap`.

The other concern is with `IntoFunction`. Right now `DynamicFunction`
trivially implements `IntoFunction` since it can just return itself. But
what should `GenericDynamicFunction` do? It could return itself wrapped
into a `DynamicFunction`, but then the API for `DynamicFunction` would
have to account for this. So then what was the point of having a
separate `GenericDynamicFunction` anyways?

And even apart from `IntoFunction`, there's nothing stopping someone
from manually creating a generic `DynamicFunction` through lying about
its `FunctionInfo` and wrapping a `GenericDynamicFunction`.

That being said, this is probably the "best" alternative if we added a
`Function` trait and stored functions as `Box<dyn Function>`.

However, I'm not convinced we gain much from this. Sure, we could keep
the API for `DynamicFunction` the same, but consumers of `Function` will
need to account for `GenericDynamicFunction` regardless (e.g. handling
multiple `FunctionInfo`, a ranged argument count, etc.). And for all
cases, except where using `DynamicFunction` directly, you end up
treating them all like `GenericDynamicFunction`.

Right now, if we did go with `GenericDynamicFunction`, the only major
benefit we'd gain would be saving 24 bytes. If memory ever does become
an issue here, we could swap over. But I think for the time being it's
better for us to pursue a clearer mental model and end-user ergonomics
through unification.

</details>

##### Using the `FunctionRegistry`

**TL;DR:** Having overloads only exist in the `FunctionRegistry`
unnecessarily splits and complicates the API.

<details>
<summary>Details</summary>

Another idea was to store the overloads in the `FunctionRegistry`. Users
would then just call functions directly through the registry (i.e.
`registry.call("my_func", my_args)`).

I didn't go with this option because of how it specifically relies on
the functions being registered. You'd not only always need access to the
registry, but you'd need to ensure that the functions you want to call
are even registered.

It also means you can't just store a generic `DynamicFunction` on a
type. Instead, you'll need to store the function's name and use that to
look up the function in the registry—even if it's only ever used by that
type.

Doing so also removes all the benefits of `DynamicFunction`, such as the
ability to pass it to functions accepting `IntoFunction`, modify it if
needed, and so on.

Like `GenericDynamicFunction` this introduces a split in the ecosystem:
you either store `DynamicFunction`, store a string to look up the
function, or force `DynamicFunction` to wrap your generic function
anyways. Or worse yet: have `DynamicFunction` wrap the lookup function
using `FunctionRegistryArc`.

</details>

#### Generic `ArgInfo`

**TL;DR:** Allowing `ArgInfo` and `ReturnInfo` to store the generic
information introduces a footgun when interpreting `FunctionInfo`.

<details>
<summary>Details</summary>

Regardless of how we represent a generic function, one thing is clear:
we need to be able to represent the information for such a function.

This PR does so by introducing a `FunctionInfoType` enum to wrap one or
more `FunctionInfo` values.

Originally, I didn't do this. I had `ArgInfo` and `ReturnInfo` allow for
generic types. This allowed us to have a single `FunctionInfo` to
represent our function, but then I realized that it actually lies about
our function.

If we have two `ArgInfo` that both allow for either `i32` or `u32`, what
does this tell us about our function? It turns out: nothing! We can't
know whether our function takes `(i32, i32)`, `(u32, u32)`, `(i32,
u32)`, or `(u32, i32)`.

It therefore makes more sense to just represent a function with multiple
`FunctionInfo` since that's really what it's made up of.

</details>

#### Flatten `FunctionInfo`

**TL;DR:** Flattening removes additional per-overload information some
users may desire and prevents us from adding more information in the
future.

<details>
<summary>Details</summary>

Why don't we just flatten multiple `FunctionInfo` into just one that can
contain multiple signatures?

This is something we could do, but I decided against it for a few
reasons:
- The only thing we'd be able to get rid of for each signature would be
the `name`. While not enough to not do it, it doesn't really suggest we
*have* to either.
- Some consumers may want access to the names of the functions that make
up the overloaded function. For example, to track a bug where an
undesirable function is being added as an overload. Or to more easily
locate the original function of an overload.
- We may eventually allow for more information to be stored on
`FunctionInfo`. For example, we may allow for documentation to be stored
like we do for `TypeInfo`. Consumers of this documentation may want
access to the documentation of each overload as they may provide
documentation specific to that overload.

</details>

## Testing

This PR adds lots of tests and benchmarks, and also adds to the example.

To run the tests:

```
cargo test --package bevy_reflect --all-features
```

To run the benchmarks:

```
cargo bench --bench reflect_function --all-features
```

To run the example:

```
cargo run --package bevy --example function_reflection --all-features
```

### Benchmarks

One of my goals with this PR was to leave the typical case of
non-overloaded functions largely unaffected by the changes introduced in
this PR. ~~And while the static size of `DynamicFunction` has increased
by 17% (from 136 to 160 bytes), the performance has generally stayed the
same~~ The static size of `DynamicFunction` has decreased from 136 to
112 bytes, while calling performance has generally stayed the same:

|                                     | `main` | 7d293ab | 252f3897d |
|-------------------------------------|--------|---------|-----------|
| `into/function`                     | 37 ns  | 46 ns   | 142 ns    |
| `with_overload/01_simple_overload`  | -      | 149 ns  | 268 ns    |
| `with_overload/01_complex_overload` | -      | 332 ns  | 431 ns    |
| `with_overload/10_simple_overload`  | -      | 1266 ns | 2618 ns   |
| `with_overload/10_complex_overload` | -      | 2544 ns | 4170 ns   |
| `call/function`                     | 57 ns  | 58 ns   | 61 ns     |
| `call/01_simple_overload`           | -      | 255 ns  | 242 ns    |
| `call/01_complex_overload`          | -      | 595 ns  | 431 ns    |
| `call/10_simple_overload`           | -      | 740 ns  | 699 ns    |
| `call/10_complex_overload`          | -      | 1824 ns | 1618 ns   |

For the overloaded function tests, the leading number indicates how many
overloads there are: `01` indicates 1 overload, `10` indicates 10
overloads. The `complex` cases have 10 unique generic types and 10
arguments, compared to the `simple` 1 generic type and 2 arguments.

I aimed to prioritize the performance of calling the functions over
creating them, hence creation speed tends to be a bit slower.

There may be other optimizations we can look into but that's probably
best saved for a future PR.

The important bit is that the standard ~~`into/function`~~ and
`call/function` benchmarks show minimal regressions. Since the latest
changes, `into/function` does have some regressions, but again the
priority was `call/function`. We can probably optimize `into/function`
if needed in the future.

---

## Showcase

Function reflection now supports [function
overloading](https://en.wikipedia.org/wiki/Function_overloading)! This
can be used to simulate generic functions:

```rust
fn add<T: Add<Output=T>>(a: T, b: T) -> T {
    a + b
}

let reflect_add = add::<i32>
    .into_function()
    .with_overload(add::<u32>)
    .with_overload(add::<f32>);

let args = ArgList::default().push_owned(25_i32).push_owned(75_i32);  
let result = func.call(args).unwrap().unwrap_owned();  
assert_eq!(result.try_take::<i32>().unwrap(), 100);  
  
let args = ArgList::default().push_owned(25.0_f32).push_owned(75.0_f32);  
let result = func.call(args).unwrap().unwrap_owned();  
assert_eq!(result.try_take::<f32>().unwrap(), 100.0);
```

You can also simulate variadic functions:

```rust
#[derive(Reflect, PartialEq, Debug)]
struct Player {
    name: Option<String>,
    health: u32,
}

// Creates a `Player` with one of the following:  
// - No name and 100 health  
// - A name and 100 health  
// - No name and custom health  
// - A name and custom health
let create_player = (|| Player {
        name: None,
        health: 100,
    })
    .into_function()
    .with_overload(|name: String| Player {
        name: Some(name),
        health: 100,
    })
    .with_overload(|health: u32| Player {
        name: None,
        health
    })
    .with_overload(|name: String, health: u32| Player {
        name: Some(name),
        health,
    });

let args = ArgList::default()
    .push_owned(String::from("Urist"))
    .push_owned(55_u32);
    
let player = create_player
    .call(args)
    .unwrap()
    .unwrap_owned()
    .try_take::<Player>()
    .unwrap();
	
assert_eq!(
    player,
    Player {
        name: Some(String::from("Urist")),
        health: 55
    }
);
```
2024-12-10 01:51:47 +00:00
Zachary Harrold
a35811d088
Add Immutable Component Support (#16372)
# Objective

- Fixes #16208

## Solution

- Added an associated type to `Component`, `Mutability`, which flags
whether a component is mutable, or immutable. If `Mutability= Mutable`,
the component is mutable. If `Mutability= Immutable`, the component is
immutable.
- Updated `derive_component` to default to mutable unless an
`#[component(immutable)]` attribute is added.
- Updated `ReflectComponent` to check if a component is mutable and, if
not, panic when attempting to mutate.

## Testing

- CI
- `immutable_components` example.

---

## Showcase

Users can now mark a component as `#[component(immutable)]` to prevent
safe mutation of a component while it is attached to an entity:

```rust
#[derive(Component)]
#[component(immutable)]
struct Foo {
    // ...
}
```

This prevents creating an exclusive reference to the component while it
is attached to an entity. This is particularly powerful when combined
with component hooks, as you can now fully track a component's value,
ensuring whatever invariants you desire are upheld. Before this would be
done my making a component private, and manually creating a `QueryData`
implementation which only permitted read access.

<details>
  <summary>Using immutable components as an index</summary>
  
```rust
/// This is an example of a component like [`Name`](bevy::prelude::Name), but immutable.
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Component)]
#[component(
    immutable,
    on_insert = on_insert_name,
    on_replace = on_replace_name,
)]
pub struct Name(pub &'static str);

/// This index allows for O(1) lookups of an [`Entity`] by its [`Name`].
#[derive(Resource, Default)]
struct NameIndex {
    name_to_entity: HashMap<Name, Entity>,
}

impl NameIndex {
    fn get_entity(&self, name: &'static str) -> Option<Entity> {
        self.name_to_entity.get(&Name(name)).copied()
    }
}

fn on_insert_name(mut world: DeferredWorld<'_>, entity: Entity, _component: ComponentId) {
    let Some(&name) = world.entity(entity).get::<Name>() else {
        unreachable!()
    };
    let Some(mut index) = world.get_resource_mut::<NameIndex>() else {
        return;
    };

    index.name_to_entity.insert(name, entity);
}

fn on_replace_name(mut world: DeferredWorld<'_>, entity: Entity, _component: ComponentId) {
    let Some(&name) = world.entity(entity).get::<Name>() else {
        unreachable!()
    };
    let Some(mut index) = world.get_resource_mut::<NameIndex>() else {
        return;
    };

    index.name_to_entity.remove(&name);
}

// Setup our name index
world.init_resource::<NameIndex>();

// Spawn some entities!
let alyssa = world.spawn(Name("Alyssa")).id();
let javier = world.spawn(Name("Javier")).id();

// Check our index
let index = world.resource::<NameIndex>();

assert_eq!(index.get_entity("Alyssa"), Some(alyssa));
assert_eq!(index.get_entity("Javier"), Some(javier));

// Changing the name of an entity is also fully capture by our index
world.entity_mut(javier).insert(Name("Steven"));

// Javier changed their name to Steven
let steven = javier;

// Check our index
let index = world.resource::<NameIndex>();

assert_eq!(index.get_entity("Javier"), None);
assert_eq!(index.get_entity("Steven"), Some(steven));
```
  
</details>

Additionally, users can use `Component<Mutability = ...>` in trait
bounds to enforce that a component _is_ mutable or _is_ immutable. When
using `Component` as a trait bound without specifying `Mutability`, any
component is applicable. However, methods which only work on mutable or
immutable components are unavailable, since the compiler must be
pessimistic about the type.

## Migration Guide

- When implementing `Component` manually, you must now provide a type
for `Mutability`. The type `Mutable` provides equivalent behaviour to
earlier versions of `Component`:
```rust
impl Component for Foo {
    type Mutability = Mutable;
    // ...
}
```
- When working with generic components, you may need to specify that
your generic parameter implements `Component<Mutability = Mutable>`
rather than `Component` if you require mutable access to said component.
- The entity entry API has had to have some changes made to minimise
friction when working with immutable components. Methods which
previously returned a `Mut<T>` will now typically return an
`OccupiedEntry<T>` instead, requiring you to add an `into_mut()` to get
the `Mut<T>` item again.

## Draft Release Notes

Components can now be made immutable while stored within the ECS.

Components are the fundamental unit of data within an ECS, and Bevy
provides a number of ways to work with them that align with Rust's rules
around ownership and borrowing. One part of this is hooks, which allow
for defining custom behavior at key points in a component's lifecycle,
such as addition and removal. However, there is currently no way to
respond to _mutation_ of a component using hooks. The reasons for this
are quite technical, but to summarize, their addition poses a
significant challenge to Bevy's core promises around performance.
Without mutation hooks, it's relatively trivial to modify a component in
such a way that breaks invariants it intends to uphold. For example, you
can use `core::mem::swap` to swap the components of two entities,
bypassing the insertion and removal hooks.

This means the only way to react to this modification is via change
detection in a system, which then begs the question of what happens
_between_ that alteration and the next run of that system?
Alternatively, you could make your component private to prevent
mutation, but now you need to provide commands and a custom `QueryData`
implementation to allow users to interact with your component at all.

Immutable components solve this problem by preventing the creation of an
exclusive reference to the component entirely. Without an exclusive
reference, the only way to modify an immutable component is via removal
or replacement, which is fully captured by component hooks. To make a
component immutable, simply add `#[component(immutable)]`:

```rust
#[derive(Component)]
#[component(immutable)]
struct Foo {
    // ...
}
```

When implementing `Component` manually, there is an associated type
`Mutability` which controls this behavior:

```rust
impl Component for Foo {
    type Mutability = Mutable;
    // ...
}
```

Note that this means when working with generic components, you may need
to specify that a component is mutable to gain access to certain
methods:

```rust
// Before
fn bar<C: Component>() {
    // ...
}

// After
fn bar<C: Component<Mutability = Mutable>>() {
    // ...
}
```

With this new tool, creating index components, or caching data on an
entity should be more user friendly, allowing libraries to provide APIs
relying on components and hooks to uphold their invariants.

## Notes

- ~~I've done my best to implement this feature, but I'm not happy with
how reflection has turned out. If any reflection SMEs know a way to
improve this situation I'd greatly appreciate it.~~ There is an
outstanding issue around the fallibility of mutable methods on
`ReflectComponent`, but the DX is largely unchanged from `main` now.
- I've attempted to prevent all safe mutable access to a component that
does not implement `Component<Mutability = Mutable>`, but there may
still be some methods I have missed. Please indicate so and I will
address them, as they are bugs.
- Unsafe is an escape hatch I am _not_ attempting to prevent. Whatever
you do with unsafe is between you and your compiler.
- I am marking this PR as ready, but I suspect it will undergo fairly
major revisions based on SME feedback.
- I've marked this PR as _Uncontroversial_ based on the feature, not the
implementation.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Benjamin Brienen <benjamin.brienen@outlook.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
Co-authored-by: Nuutti Kotivuori <naked@iki.fi>
2024-12-05 14:27:48 +00:00
andriyDev
b1e4512648
Fix the picking backend features not actually disabling the features (#16470)
# Objective

- Fixes #16469.

## Solution

- Make the picking backend features not enabled by default in each
sub-crate.
- Make features in `bevy_internal` to set the backend features
- Make the root `bevy` crate set the features by default.

## Testing

- The mesh and sprite picking examples still work correctly.
2024-11-22 18:14:16 +00:00
Joona Aalto
3ada15ee1c
Add more Glam types and constructors to prelude (#16261)
# Objective

Glam has some common and useful types and helpers that are not in the
prelude of `bevy_math`. This includes shorthand constructors like
`vec3`, or even `Vec3A`, the aligned version of `Vec3`.

```rust
// The "normal" way to create a 3D vector
let vec = Vec3::new(2.0, 1.0, -3.0);

// Shorthand version
let vec = vec3(2.0, 1.0, -3.0);
```

## Solution

Add the following types and methods to the prelude:

- `vec2`, `vec3`, `vec3a`, `vec4`
- `uvec2`, `uvec3`, `uvec4`
- `ivec2`, `ivec3`, `ivec4`
- `bvec2`, `bvec3`, `bvec3a`, `bvec4`, `bvec4a`
- `mat2`, `mat3`, `mat3a`, `mat4`
- `quat` (not sure if anyone uses this, but for consistency)
- `Vec3A`
- `BVec3A`, `BVec4A`
- `Mat3A`

I did not add the u16, i16, or f64 variants like `dvec2`, since there
are currently no existing types like those in the prelude.

The shorthand constructors are currently used a lot in some places in
Bevy, and not at all in others. In a follow-up, we might want to
consider if we have a preference for the shorthand, and make a PR to
change the codebase to use it more consistently.
2024-11-11 18:47:16 +00:00
Benjamin Brienen
4df8b1998e
Allow or fix dead code in benches (#16282)
# Objective

Fixes #15806

## Solution

Fix an undeclared module and expect `dead_code`.

## Testing

Run this command and see no `dead_code` warnings.

`cargo +nightly check --benches --target-dir ../target --manifest-path
./benches/Cargo.toml`
2024-11-07 22:19:07 +00:00
Aevyrie
54b323ec80
Mesh picking fixes (#16110)
# Objective

- Mesh picking is noisy when a non triangle list is used
- Mesh picking runs even when users don't need it
- Resolve #16065 

## Solution

- Don't add the mesh picking plugin by default
- Remove error spam
2024-10-27 19:03:48 +00:00
MiniaczQ
e5e44888c6
Validate param benchmarks (#15885)
# Objective

Benchmark overhead of validation for:
- `DynSystemParam`,
- `ParamSet`,
- combinator systems.

Needed for #15606

## Solution

As noted in objective, I've added 3 benchmarks, where each uses an
excessive amount of the specific functionality.
I benchmark on the level of schedules, rather than individual
`validate_param` calls, so we get a better idea how changes to the code
impact memory-lookup, etc. related side effects.

## Testing

```
param/combinator_system/8_piped_systems
                        time:   [1.7560 µs 1.7865 µs 1.8180 µs]
                        change: [+4.5244% +6.7955% +9.1413%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 2 outliers among 100 measurements (2.00%)
  1 (1.00%) high mild
  1 (1.00%) high severe

param/combinator_system/8_dyn_params_system
                        time:   [89.354 ns 89.790 ns 90.300 ns]
                        change: [+0.6751% +1.6825% +2.6842%] (p = 0.00 < 0.05)
                        Change within noise threshold.
Found 9 outliers among 100 measurements (9.00%)
  6 (6.00%) high mild
  3 (3.00%) high severe

param/combinator_system/8_variant_param_set_system
                        time:   [88.295 ns 89.202 ns 90.208 ns]
                        change: [+0.1320% +1.0060% +1.8482%] (p = 0.02 < 0.05)
                        Change within noise threshold.
Found 4 outliers among 100 measurements (4.00%)
  4 (4.00%) high mild
```

2 back-to-back runs of the benchmarks, there is quire a lot of noise,
can use feedback on fixing that
2024-10-15 02:38:22 +00:00
Pablo Reinhardt
d96a9d15f6
Migrate from Query::single and friends to Single (#15872)
# Objective

- closes #15866

## Solution

- Simply migrate where possible.

## Testing

- Expect that CI will do most of the work. Examples is another way of
testing this, as most of the work is in that area.
---

## Notes
For now, this PR doesn't migrate `QueryState::single` and friends as for
now, this look like another issue. So for example, QueryBuilders that
used single or `World::query` that used single wasn't migrated. If there
is a easy way to migrate those, please let me know.

Most of the uses of `Query::single` were removed, the only other uses
that I found was related to tests of said methods, so will probably be
removed when we remove `Query::single`.
2024-10-13 20:32:06 +00:00
JaySpruce
3d6b24880e
Add insert_batch and variations (#15702)
# Objective

`insert_or_spawn_batch` exists, but a version for just inserting doesn't
- Closes #2693 
- Closes #8384 
- Adopts/supersedes #8600 

## Solution

Add `insert_batch`, along with the most common `insert` variations:
- `World::insert_batch`
- `World::insert_batch_if_new`
- `World::try_insert_batch`
- `World::try_insert_batch_if_new`
- `Commands::insert_batch`
- `Commands::insert_batch_if_new`
- `Commands::try_insert_batch`
- `Commands::try_insert_batch_if_new`

## Testing

Added tests, and added a benchmark for `insert_batch`.
Performance is slightly better than `insert_or_spawn_batch` when only
inserting:


![Code_HPnUN0QeWe](https://github.com/user-attachments/assets/53091e4f-6518-43f4-a63f-ae57d5470c66)

<details>
<summary>old benchmark</summary>

This was before reworking it to remove the `UnsafeWorldCell`:


![Code_QhXJb8sjlJ](https://github.com/user-attachments/assets/1061e2a7-a521-48e1-a799-1b6b8d1c0b93)
</details>

---

## Showcase

Usage is the same as `insert_or_spawn_batch`:
```
use bevy_ecs::{entity::Entity, world::World, component::Component};
#[derive(Component)]
struct A(&'static str);
#[derive(Component, PartialEq, Debug)]
struct B(f32);

let mut world = World::new();
let entity_a = world.spawn_empty().id();
let entity_b = world.spawn_empty().id();
world.insert_batch([
    (entity_a, (A("a"), B(0.0))),
    (entity_b, (A("b"), B(1.0))),
]);

assert_eq!(world.get::<B>(entity_a), Some(&B(0.0)));

```
2024-10-13 18:14:16 +00:00
Joona Aalto
0e30b68b20
Add mesh picking backend and MeshRayCast system parameter (#15800)
# Objective

Closes #15545.

`bevy_picking` supports UI and sprite picking, but not mesh picking.
Being able to pick meshes would be extremely useful for various games,
tools, and our own examples, as well as scene editors and inspectors.
So, we need a mesh picking backend!

Luckily,
[`bevy_mod_picking`](https://github.com/aevyrie/bevy_mod_picking) (which
`bevy_picking` is based on) by @aevyrie already has a [backend for
it](74f0c3c0fb/backends/bevy_picking_raycast/src/lib.rs)
using [`bevy_mod_raycast`](https://github.com/aevyrie/bevy_mod_raycast).
As a side product of adding mesh picking, we also get support for
performing ray casts on meshes!

## Solution

Upstream a large chunk of the immediate-mode ray casting functionality
from `bevy_mod_raycast`, and add a mesh picking backend based on
`bevy_mod_picking`. Huge thanks to @aevyrie who did all the hard work on
these incredible crates!

All meshes are pickable by default. Picking can be disabled for
individual entities by adding `PickingBehavior::IGNORE`, like normal.
Or, if you want mesh picking to be entirely opt-in, you can set
`MeshPickingBackendSettings::require_markers` to `true` and add a
`RayCastPickable` component to the desired camera and target entities.

You can also use the new `MeshRayCast` system parameter to cast rays
into the world manually:

```rust
fn ray_cast_system(mut ray_cast: MeshRayCast, foo_query: Query<(), With<Foo>>) {
    let ray = Ray3d::new(Vec3::ZERO, Dir3::X);

    // Only ray cast against entities with the `Foo` component.
    let filter = |entity| foo_query.contains(entity);

    // Never early-exit. Note that you can change behavior per-entity.
    let early_exit_test = |_entity| false;

    // Ignore the visibility of entities. This allows ray casting hidden entities.
    let visibility = RayCastVisibility::Any;

    let settings = RayCastSettings::default()
        .with_filter(&filter)
        .with_early_exit_test(&early_exit_test)
        .with_visibility(visibility);

    // Cast the ray with the settings, returning a list of intersections.
    let hits = ray_cast.cast_ray(ray, &settings);
}
```

This is largely a direct port, but I did make several changes to match
our APIs better, remove things we don't need or that I think are
unnecessary, and do some general improvements to code quality and
documentation.

### Changes Relative to `bevy_mod_raycast` and `bevy_mod_picking`

- Every `Raycast` and "raycast" has been renamed to `RayCast` and "ray
cast" (similar reasoning as the "Naming" section in #15724)
- `Raycast` system param has been renamed to `MeshRayCast` to avoid
naming conflicts and to be explicit that it is not for colliders
- `RaycastBackend` has been renamed to `MeshPickingBackend`
- `RayCastVisibility` variants are now `Any`, `Visible`, and
`VisibleInView` instead of `Ignore`, `MustBeVisible`, and
`MustBeVisibleAndInView`
- `NoBackfaceCulling` has been renamed to `RayCastBackfaces`, to avoid
implying that it affects the rendering of backfaces for meshes (it
doesn't)
- `SimplifiedMesh` and `RayCastBackfaces` live near other ray casting
API types, not in their own 10 LoC module
- All intersection logic and types are in the same `intersections`
module, not split across several modules
- Some intersection types have been renamed to be clearer and more
consistent
	- `IntersectionData` -> `RayMeshHit` 
	- `RayHit` -> `RayTriangleHit`
- General documentation and code quality improvements

### Removed / Not Ported

- Removed unused ray helpers and types, like `PrimitiveIntersection`
- Removed getters on intersection types, and made their properties
public
- There is no `2d` feature, and `Raycast::mesh_query` and
`Raycast::mesh2d_query` have been merged into `MeshRayCast::mesh_query`,
which handles both 2D and 3D
- I assume this existed previously because `Mesh2dHandle` used to be in
`bevy_sprite`. Now both the 2D and 3D mesh are in `bevy_render`.
- There is no `debug` feature or ray debug rendering
- There is no deferred API (`RaycastSource`)
- There is no `CursorRayPlugin` (the picking backend handles this)

### Note for Reviewers

In case it's helpful, the [first
commit](281638ef10)
here is essentially a one-to-one port. The rest of the commits are
primarily refactoring and cleaning things up in the ways listed earlier,
as well as changes to the module structure.

It may also be useful to compare the original [picking
backend](74f0c3c0fb/backends/bevy_picking_raycast/src/lib.rs)
and [`bevy_mod_raycast`](https://github.com/aevyrie/bevy_mod_raycast) to
this PR. Feel free to mention if there are any changes that I should
revert or something I should not include in this PR.

## Testing

I tested mesh picking and relevant components in some examples, for both
2D and 3D meshes, and added a new `mesh_picking` example. I also
~~stole~~ ported over the [ray-mesh intersection
benchmark](dbc5ef32fe/benches/ray_mesh_intersection.rs)
from `bevy_mod_raycast`.

---

## Showcase

Below is a version of the `2d_shapes` example modified to demonstrate 2D
mesh picking. This is not included in this PR.


https://github.com/user-attachments/assets/7742528c-8630-4c00-bacd-81576ac432bf

And below is the new `mesh_picking` example:


https://github.com/user-attachments/assets/b65c7a5a-fa3a-4c2d-8bbd-e7a2c772986e

There is also a really cool new `mesh_ray_cast` example ported over from
`bevy_mod_raycast`:


https://github.com/user-attachments/assets/3c5eb6c0-bd94-4fb0-bec6-8a85668a06c9

---------

Co-authored-by: Aevyrie <aevyrie@gmail.com>
Co-authored-by: Trent <2771466+tbillington@users.noreply.github.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2024-10-13 17:24:19 +00:00
Christian Hughes
219b5930f1
Rename App/World::observe to add_observer, EntityWorldMut::observe_entity to observe. (#15754)
# Objective

- Closes #15752

Calling the functions `App::observe` and `World::observe` doesn't make
sense because you're not "observing" the `App` or `World`, you're adding
an observer that listens for an event that occurs *within* the `World`.
We should rename them to better fit this.

## Solution

Renames:
- `App::observe` -> `App::add_observer`
- `World::observe` -> `World::add_observer`
- `Commands::observe` -> `Commands::add_observer`
- `EntityWorldMut::observe_entity` -> `EntityWorldMut::observe`

(Note this isn't a breaking change as the original rename was introduced
earlier this cycle.)

## Testing

Reusing current tests.
2024-10-09 15:39:29 +00:00
Trashtalk217
d1bd46d45e
Deprecate get_or_spawn (#15652)
# Objective

After merging retained rendering world #15320, we now have a good way of
creating a link between worlds (*HIYAA intensifies*). This means that
`get_or_spawn` is no longer necessary for that function. Entity should
be opaque as the warning above `get_or_spawn` says. This is also part of
#15459.

I'm deprecating `get_or_spawn_batch` in a different PR in order to keep
the PR small in size.

## Solution

Deprecate `get_or_spawn` and replace it with `get_entity` in most
contexts. If it's possible to query `&RenderEntity`, then the entity is
synced and `render_entity.id()` is initialized in the render world.

## Migration Guide

If you are given an `Entity` and you want to do something with it, use
`Commands.entity(...)` or `World.entity(...)`. If instead you want to
spawn something use `Commands.spawn(...)` or `World.spawn(...)`. If you
are not sure if an entity exists, you can always use `get_entity` and
match on the `Option<...>` that is returned.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-10-07 16:08:22 +00:00
Kristoffer Søholm
336c23c1aa
Rename observe to observe_entity on EntityWorldMut (#15616)
# Objective

The current observers have some unfortunate footguns where you can end
up confused about what is actually being observed. For apps you can
chain observe like `app.observe(..).observe(..)` which works like you
would expect, but if you try the same with world the first `observe()`
will return the `EntityWorldMut` for the created observer, and the
second `observe()` will only observe on the observer entity. It took
several hours for multiple people on discord to figure this out, which
is not a great experience.

## Solution

Rename `observe` on entities to `observe_entity`. It's slightly more
verbose when you know you have an entity, but it feels right to me that
observers for specific things have more specific naming, and it prevents
this issue completely.

Another possible solution would be to unify `observe` on `App` and
`World` to have the same kind of return type, but I'm not sure exactly
what that would look like.

## Testing

Simple name change, so only concern is docs really.

---


## Migration Guide

The `observe()` method on entities has been renamed to
`observe_entity()` to prevent confusion about what is being observed in
some cases.
2024-10-03 17:05:26 +00:00
rudderbucky
2da8d17a44
Add try_despawn methods to World/Commands (#15480)
# Objective

Fixes #14511.

`despawn` allows you to remove entities from the world. However, if the
entity does not exist, it emits a warning. This may not be intended
behavior for many users who have use cases where they need to call
`despawn` regardless of if the entity actually exists (see the issue),
or don't care in general if the entity already doesn't exist.

(Also trying to gauge interest on if this feature makes sense, I'd
personally love to have it, but I could see arguments that this might be
a footgun. Just trying to help here 😄 If there's no contention I could
also implement this for `despawn_recursive` and `despawn_descendants` in
the same PR)

## Solution

Add `try_despawn`, `try_despawn_recursive` and
`try_despawn_descendants`.

Modify `World::despawn_with_caller` to also take in a `warn` boolean
argument, which is then considered when logging the warning. Set
`log_warning` to `true` in the case of `despawn`, and `false` in the
case of `try_despawn`.

## Testing

Ran `cargo run -p ci` on macOS, it seemed fine.
2024-10-03 16:21:05 +00:00
rudderbucky
5e81154e9c
Despawn and despawn_recursive benchmarks (#15610)
# Objective

Add despawn and despawn_recursive benchmarks in a similar vein to the
spawn benchmark.

## Testing

Ran `cargo bench` from `benches` and it compiled fine.

On my machine:
```
despawn_world/1_entities
                        time:   [3.1495 ns 3.1574 ns 3.1652 ns]
Found 4 outliers among 100 measurements (4.00%)
  3 (3.00%) high mild
  1 (1.00%) high severe
despawn_world/10_entities
                        time:   [28.629 ns 28.674 ns 28.720 ns]
Found 3 outliers among 100 measurements (3.00%)
  2 (2.00%) high mild
  1 (1.00%) high severe
despawn_world/100_entities
                        time:   [286.95 ns 287.41 ns 287.90 ns]
Found 5 outliers among 100 measurements (5.00%)
  5 (5.00%) high mild
despawn_world/1000_entities
                        time:   [2.8739 µs 2.9001 µs 2.9355 µs]
Found 7 outliers among 100 measurements (7.00%)
  1 (1.00%) high mild
  6 (6.00%) high severe
despawn_world/10000_entities
                        time:   [28.535 µs 28.617 µs 28.698 µs]
Found 2 outliers among 100 measurements (2.00%)
  1 (1.00%) high mild
  1 (1.00%) high severe

despawn_world_recursive/1_entities
                        time:   [5.2270 ns 5.2507 ns 5.2907 ns]
Found 11 outliers among 100 measurements (11.00%)
  1 (1.00%) low mild
  6 (6.00%) high mild
  4 (4.00%) high severe
despawn_world_recursive/10_entities
                        time:   [57.495 ns 57.590 ns 57.691 ns]
Found 2 outliers among 100 measurements (2.00%)
  1 (1.00%) low mild
  1 (1.00%) high mild
despawn_world_recursive/100_entities
                        time:   [514.43 ns 518.91 ns 526.88 ns]
Found 4 outliers among 100 measurements (4.00%)
  1 (1.00%) high mild
  3 (3.00%) high severe
despawn_world_recursive/1000_entities
                        time:   [5.0362 µs 5.0463 µs 5.0578 µs]
Found 7 outliers among 100 measurements (7.00%)
  2 (2.00%) high mild
  5 (5.00%) high severe
despawn_world_recursive/10000_entities
                        time:   [51.159 µs 51.603 µs 52.215 µs]
Found 9 outliers among 100 measurements (9.00%)
  3 (3.00%) high mild
  6 (6.00%) high severe
```
2024-10-03 14:59:37 +00:00