Commit Graph

2345 Commits

Author SHA1 Message Date
ickshonpe
45a3f3d138
Color interpolation in OKLab, OKLCH spaces for UI gradients (#19330)
# Objective

Add support for interpolation in OKLab and OKLCH color spaces for UI
gradients.

## Solution
* New `InterpolationColorSpace` enum with `OkLab`, `OkLch`, `OkLchLong`,
`Srgb` and `LinearRgb` variants.
  * Added a color space specialization to the gradients pipeline.
* Added support for interpolation in OkLCH and OkLAB color spaces to the
gradients shader. OKLCH interpolation supports both short and long hue
paths. This is mostly based on the conversion functions from
`bevy_color` except that interpolation in polar space uses radians.
  * Added `color_space` fields to each gradient type.

## Testing

The `gradients` example has been updated to demonstrate the different
color interpolation methods.
Press space to cycle through the different options.

---

## Showcase


![color_spaces](https://github.com/user-attachments/assets/e10f8342-c3c8-487e-b386-7acdf38d638f)
2025-06-21 15:06:35 +00:00
Lucas Franca
8f08d6bc86
Move usages folder to usage (#19757)
# Objective

There were 2 folders inside of `examples`, each with 1 example, and with
similar folder names.

## Solution

Move the example in the `usages` folder to `usage`.

## Testing
 
`cargo run -p ci`
2025-06-21 00:06:44 +00:00
Jan Hohenheim
ffd6c9e1c9
Rewrite camera shake example (#19724)
# Objective

- Alternative to #19721
- The old implementation had several issues:
  - underexplained
  - bit complicated in places
  - did not follow the source as described
    - camera moves away
    - camera does not use noise
- camera nudges back after shake ends, which looks cinematic, but not
what you want in practice

All in all: the old implementation did not really show a typical
implementation IMO

## Solution

- Rewrite it :D
- I believe the current implementation is a robust thing you can learn
from or just copy-paste into your project

## Testing


https://github.com/user-attachments/assets/bfe74fb6-c428-4d5a-9c9c-cd4a034ba176

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2025-06-20 16:43:14 +00:00
Talin
9fdddf7089
Core Checkbox (#19665)
# Objective

This is part of the "core widgets" effort:
https://github.com/bevyengine/bevy/issues/19236.

## Solution

This adds the "core checkbox" widget type.

## Testing

Tested using examples core_widgets and core_widgets_observers.

Note to reviewers: I reorganized the code in the examples, so the diffs
are large because of code moves.
2025-06-20 16:37:18 +00:00
François Mockers
4e694aea53
ECS: put strings only used for debug behind a feature (#19558)
# Objective

- Many strings in bevy_ecs are created but only used for debug: system
name, component name, ...
- Those strings make a significant part of the final binary and are no
use in a released game

## Solution

- Use [`strings`](https://linux.die.net/man/1/strings) to find ...
strings in a binary
- Try to find where they come from
- Many are made from `type_name::<T>()` and only used in error / debug
messages
- Add a new structure `DebugName` that holds no value if `debug` feature
is disabled
- Replace `core::any::type_name::<T>()` by `DebugName::type_name::<T>()`

## Testing

Measurements were taken without the new feature being enabled by
default, to help with commands

### File Size

I tried building the `breakout` example with `cargo run --release
--example breakout`

|`debug` enabled|`debug` disabled|
|-|-|
|81621776 B|77735728B|
|77.84MB|74.13MB|

### Compilation time

`hyperfine --min-runs 15 --prepare "cargo clean && sleep 5"
'RUSTC_WRAPPER="" cargo build --release --example breakout'
'RUSTC_WRAPPER="" cargo build --release --example breakout --features
debug'`

```
breakout' 'RUSTC_WRAPPER="" cargo build --release --example breakout --features debug'
Benchmark 1: RUSTC_WRAPPER="" cargo build --release --example breakout
  Time (mean ± σ):     84.856 s ±  3.565 s    [User: 1093.817 s, System: 32.547 s]
  Range (min … max):   78.038 s … 89.214 s    15 runs

Benchmark 2: RUSTC_WRAPPER="" cargo build --release --example breakout --features debug
  Time (mean ± σ):     92.303 s ±  2.466 s    [User: 1193.443 s, System: 33.803 s]
  Range (min … max):   90.619 s … 99.684 s    15 runs

Summary
  RUSTC_WRAPPER="" cargo build --release --example breakout ran
    1.09 ± 0.05 times faster than RUSTC_WRAPPER="" cargo build --release --example breakout --features debug
```
2025-06-18 20:15:25 +00:00
Kristoffer Søholm
2119838e27
Add support for ButtonInput<Key> (#19684)
# Objective

While `KeyCode` is very often the correct way to interact with keyboard
input there are a bunch of cases where it isn't, notably most of the
symbols (e.g. plus, minus, different parentheses). Currently the only
way to get these is to read from `EventReader<KeyboardInput>`, but then
you'd have to redo the `ButtonInput` logic for pressed/released to e.g.
make zoom functionality that depends on plus/minus keys.

This has led to confusion previously, like
https://github.com/bevyengine/bevy/issues/3278

## Solution

Add a `ButtonInput<Key>` resource.

## Testing

Modified the `keyboard_input` example to test it.

## Open questions

I'm not 100% sure this is the right way forward, since it duplicates the
key processing logic and might make people use the shorter
`ButtonInput<Key>` even when it's not appropriate.

Another option is to add a new struct with both `Key` and `KeyCode`, and
use `ButtonInput` with that instead. That would make it more
explanatory, but that is a lot of churn.

The third alternative is to not do this because it's too niche.

I'll add more documentation and take it out of draft if we want to move
forward with it.
2025-06-18 20:15:03 +00:00
Alice Cecile
1079b83af9
Revert "bevy_log: refactor how log layers are wired together (#19248)" (#19705)
This reverts commit 8661e914a5, aka
#19248.

Fixes #19689.
2025-06-17 20:41:30 +00:00
Jan Hohenheim
a750cfe4a1
Split CursorOptions off of Window (#19668)
# Objective

- Fixes #19627 
- Tackles part of #19644 
- Supersedes #19629
- `Window` has become a very very very big component
- As such, our change detection does not *really* work on it, as e.g.
moving the mouse will cause a change for the entire window
- We circumvented this with a cache
- But, some things *shouldn't* be cached as they can be changed from
outside the user's control, notably the cursor grab mode on web
- So, we need to disable the cache for that
- But because change detection is broken, that would result in the
cursor grab mode being set every frame the mouse is moved
- That is usually *not* what a dev wants, as it forces the cursor to be
locked even when the end-user is trying to free the cursor on the
browser
  - the cache in this situation is invalid due to #8949

## Solution

- Split `Window` into multiple components, each with working change
detection
- Disable caching of the cursor grab mode
- This will only attempt to force the grab mode when the `CursorOptions`
were touched by the user, which is *much* rarer than simply moving the
mouse.
- If this PR is merged, I'll do the exact same for the other
constituents of `Window` as a follow-up

## Testing

- Ran all the changed examples
2025-06-17 20:20:13 +00:00
SilentSpaceTraveller
8661e914a5
bevy_log: refactor how log layers are wired together (#19248)
# Objective

Current way to wire `Layer`s together using `layer.with(new_layer)` in
the `bevy_log` plugin is brittle and not flexible. As #17722
demonstrated, the current solution makes it very hard to do any kind of
advanced wiring, as the type system of `tracing::Subscriber` gets in the
way very quickly (the type of each new layer depends on the type of the
previous ones). We want to make it easier to have more complex wiring of
`Layers`. It would be hard to solve #19085 without it

## Solution
It aims to be functionally equivalent.
- Replace of using `layer.with(new_layer)` . We now add `layer.boxed()`
to a `Vec<BoxedLayer>`. It is a solution recommended by
`tracing_subscriber::Layer` for complex wiring cases (See
https://docs.rs/tracing-subscriber/latest/tracing_subscriber/layer/index.html#runtime-configuration-with-layers)
- Do some refactoring and clean up that is now enabled by the new
solution

## Testing
- Ran CI locally on Linux
- Ran the logs examples
- Need people familiar with the features `trace`, `tracing-chrome`,
`tracing-tracy` to check that it still works as expected
- Need people with access to `ios`, `android` and `wasm` to check it as
well.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
2025-06-16 21:30:55 +00:00
Chris Russell
f7e112a3c9
Let query items borrow from query state to avoid needing to clone (#15396)
# Objective

Improve the performance of `FilteredEntity(Ref|Mut)` and
`Entity(Ref|Mut)Except`.

`FilteredEntityRef` needs an `Access<ComponentId>` to determine what
components it can access. There is one stored in the query state, but
query items cannot borrow from the state, so it has to `clone()` the
access for each row. Cloning the access involves memory allocations and
can be expensive.


## Solution

Let query items borrow from their query state.  

Add an `'s` lifetime to `WorldQuery::Item` and `WorldQuery::Fetch`,
similar to the one in `SystemParam`, and provide `&'s Self::State` to
the fetch so that it can borrow from the state.

Unfortunately, there are a few cases where we currently return query
items from temporary query states: the sorted iteration methods create a
temporary state to query the sort keys, and the
`EntityRef::components<Q>()` methods create a temporary state for their
query.

To allow these to continue to work with most `QueryData`
implementations, introduce a new subtrait `ReleaseStateQueryData` that
converts a `QueryItem<'w, 's>` to `QueryItem<'w, 'static>`, and is
implemented for everything except `FilteredEntity(Ref|Mut)` and
`Entity(Ref|Mut)Except`.

`#[derive(QueryData)]` will generate `ReleaseStateQueryData`
implementations that apply when all of the subqueries implement
`ReleaseStateQueryData`.

This PR does not actually change the implementation of
`FilteredEntity(Ref|Mut)` or `Entity(Ref|Mut)Except`! That will be done
as a follow-up PR so that the changes are easier to review. I have
pushed the changes as chescock/bevy#5.

## Testing

I ran performance traces of many_foxes, both against main and against
chescock/bevy#5, both including #15282. These changes do appear to make
generalized animation a bit faster:

(Red is main, yellow is chescock/bevy#5)

![image](https://github.com/user-attachments/assets/de900117-0c6a-431d-ab62-c013834f97a9)


## Migration Guide

The `WorldQuery::Item` and `WorldQuery::Fetch` associated types and the
`QueryItem` and `ROQueryItem` type aliases now have an additional
lifetime parameter corresponding to the `'s` lifetime in `Query`. Manual
implementations of `WorldQuery` will need to update the method
signatures to include the new lifetimes. Other uses of the types will
need to be updated to include a lifetime parameter, although it can
usually be passed as `'_`. In particular, `ROQueryItem` is used when
implementing `RenderCommand`.

Before: 

```rust
fn render<'w>(
    item: &P,
    view: ROQueryItem<'w, Self::ViewQuery>,
    entity: Option<ROQueryItem<'w, Self::ItemQuery>>,
    param: SystemParamItem<'w, '_, Self::Param>,
    pass: &mut TrackedRenderPass<'w>,
) -> RenderCommandResult;
```

After: 

```rust
fn render<'w>(
    item: &P,
    view: ROQueryItem<'w, '_, Self::ViewQuery>,
    entity: Option<ROQueryItem<'w, '_, Self::ItemQuery>>,
    param: SystemParamItem<'w, '_, Self::Param>,
    pass: &mut TrackedRenderPass<'w>,
) -> RenderCommandResult;
```

---

Methods on `QueryState` that take `&mut self` may now result in
conflicting borrows if the query items capture the lifetime of the
mutable reference. This affects `get()`, `iter()`, and others. To fix
the errors, first call `QueryState::update_archetypes()`, and then
replace a call `state.foo(world, param)` with
`state.query_manual(world).foo_inner(param)`. Alternately, you may be
able to restructure the code to call `state.query(world)` once and then
make multiple calls using the `Query`.

Before:
```rust
let mut state: QueryState<_, _> = ...;
let d1 = state.get(world, e1);
let d2 = state.get(world, e2); // Error: cannot borrow `state` as mutable more than once at a time
println!("{d1:?}");
println!("{d2:?}");
```

After: 
```rust
let mut state: QueryState<_, _> = ...;

state.update_archetypes(world);
let d1 = state.get_manual(world, e1);
let d2 = state.get_manual(world, e2);
// OR
state.update_archetypes(world);
let d1 = state.query(world).get_inner(e1);
let d2 = state.query(world).get_inner(e2);
// OR
let query = state.query(world);
let d1 = query.get_inner(e1);
let d1 = query.get_inner(e2);

println!("{d1:?}");
println!("{d2:?}");
```
2025-06-16 21:05:41 +00:00
Alice Cecile
b7d2cb8547
Provide access to the original target of entity-events in observers (#19663)
# Objective

Getting access to the original target of an entity-event is really
helpful when working with bubbled / propagated events.

`bevy_picking` special-cases this, but users have requested this for all
sorts of bubbled events.

The existing naming convention was also very confusing. Fixes
https://github.com/bevyengine/bevy/issues/17112, but also see #18982.

## Solution

1. Rename `ObserverTrigger::target` -> `current_target`.
1. Store `original_target: Option<Entity>` in `ObserverTrigger`.
1. Wire it up so this field gets set correctly.
1. Remove the `target` field on the `Pointer` events from
`bevy_picking`.

Closes https://github.com/bevyengine/bevy/pull/18710, which attempted
the same thing. Thanks @emfax!

## Testing

I've modified an existing test to check that the entities returned
during event bubbling / propagation are correct.

## Notes to reviewers

It's a little weird / sad that you can no longer access this infromation
via the buffered events for `Pointer`. That said, you already couldn't
access any bubbled target. We should probably remove the `BufferedEvent`
form of `Pointer` to reduce confusion and overhead, but I didn't want to
do so here.

Observer events can be trivially converted into buffered events (write
an observer with an EventWriter), and I suspect that that is the better
migration if you want the controllable timing or performance
characteristics of buffered events for your specific use case.

## Future work

It would be nice to not store this data at all (and not expose any
methods) if propagation was disabled. That involves more trait
shuffling, and I don't think we should do it here for reviewability.

---------

Co-authored-by: Joona Aalto <jondolf.dev@gmail.com>
2025-06-15 20:53:25 +00:00
Rosy
83a1c07c01
lighting.rs example: Improved ambient light showcase (#19658)
# Objective

As someone who is currently learning Bevy, I found the implementation of
the ambient light in the 3d/lighting.rs example unsatisfactory.

## Solution

- I adjusted the brightness of the ambient light in the scene to 200
(where the default is 80). It was previously 0.02, a value so low it has
no noticeable effect.
- I added a keybind (space bar) to toggle the ambient light, allowing
users to see the difference it makes. I also added text showing the
state of the ambient light (on, off) and text showing the keybind.

I'm very new to Bevy and Rust, so apologies if any of this code is not
up to scratch.

## Testing

I checked all the text still updates correctly and all keybinds still
work. In my testing, it looks to work okay.
I'd appreciate others testing too, just to make sure. 

---

## Showcase

<details>
  <summary>Click to view showcase</summary>
<img width="960" alt="Screenshot (11)"
src="https://github.com/user-attachments/assets/916e569e-cd49-43fd-b81d-aae600890cd3"
/>
<img width="959" alt="Screenshot (12)"
src="https://github.com/user-attachments/assets/0e16bb3a-c38a-4a8d-8248-edf3b820d238"
/>
</details>
2025-06-15 16:49:48 +00:00
Joona Aalto
38c3423693
Event Split: Event, EntityEvent, and BufferedEvent (#19647)
# Objective

Closes #19564.

The current `Event` trait looks like this:

```rust
pub trait Event: Send + Sync + 'static {
    type Traversal: Traversal<Self>;
    const AUTO_PROPAGATE: bool = false;
    
    fn register_component_id(world: &mut World) -> ComponentId { ... }
    fn component_id(world: &World) -> Option<ComponentId> { ... }
}
```

The `Event` trait is used by both buffered events
(`EventReader`/`EventWriter`) and observer events. If they are observer
events, they can optionally be targeted at specific `Entity`s or
`ComponentId`s, and can even be propagated to other entities.

However, there has long been a desire to split the trait semantically
for a variety of reasons, see #14843, #14272, and #16031 for discussion.
Some reasons include:

- It's very uncommon to use a single event type as both a buffered event
and targeted observer event. They are used differently and tend to have
distinct semantics.
- A common footgun is using buffered events with observers or event
readers with observer events, as there is no type-level error that
prevents this kind of misuse.
- #19440 made `Trigger::target` return an `Option<Entity>`. This
*seriously* hurts ergonomics for the general case of entity observers,
as you need to `.unwrap()` each time. If we could statically determine
whether the event is expected to have an entity target, this would be
unnecessary.

There's really two main ways that we can categorize events: push vs.
pull (i.e. "observer event" vs. "buffered event") and global vs.
targeted:

|              | Push            | Pull                        |
| ------------ | --------------- | --------------------------- |
| **Global**   | Global observer | `EventReader`/`EventWriter` |
| **Targeted** | Entity observer | -                           |

There are many ways to approach this, each with their tradeoffs.
Ultimately, we kind of want to split events both ways:

- A type-level distinction between observer events and buffered events,
to prevent people from using the wrong kind of event in APIs
- A statically designated entity target for observer events to avoid
accidentally using untargeted events for targeted APIs

This PR achieves these goals by splitting event traits into `Event`,
`EntityEvent`, and `BufferedEvent`, with `Event` being the shared trait
implemented by all events.

## `Event`, `EntityEvent`, and `BufferedEvent`

`Event` is now a very simple trait shared by all events.

```rust
pub trait Event: Send + Sync + 'static {
    // Required for observer APIs
    fn register_component_id(world: &mut World) -> ComponentId { ... }
    fn component_id(world: &World) -> Option<ComponentId> { ... }
}
```

You can call `trigger` for *any* event, and use a global observer for
listening to the event.

```rust
#[derive(Event)]
struct Speak {
    message: String,
}

// ...

app.add_observer(|trigger: On<Speak>| {
    println!("{}", trigger.message);
});

// ...

commands.trigger(Speak {
    message: "Y'all like these reworked events?".to_string(),
});
```

To allow an event to be targeted at entities and even propagated
further, you can additionally implement the `EntityEvent` trait:

```rust
pub trait EntityEvent: Event {
    type Traversal: Traversal<Self>;
    const AUTO_PROPAGATE: bool = false;
}
```

This lets you call `trigger_targets`, and to use targeted observer APIs
like `EntityCommands::observe`:

```rust
#[derive(Event, EntityEvent)]
#[entity_event(traversal = &'static ChildOf, auto_propagate)]
struct Damage {
    amount: f32,
}

// ...

let enemy = commands.spawn((Enemy, Health(100.0))).id();

// Spawn some armor as a child of the enemy entity.
// When the armor takes damage, it will bubble the event up to the enemy.
let armor_piece = commands
    .spawn((ArmorPiece, Health(25.0), ChildOf(enemy)))
    .observe(|trigger: On<Damage>, mut query: Query<&mut Health>| {
        // Note: `On::target` only exists because this is an `EntityEvent`.
        let mut health = query.get(trigger.target()).unwrap();
        health.0 -= trigger.amount();
    });

commands.trigger_targets(Damage { amount: 10.0 }, armor_piece);
```

> [!NOTE]
> You *can* still also trigger an `EntityEvent` without targets using
`trigger`. We probably *could* make this an either-or thing, but I'm not
sure that's actually desirable.

To allow an event to be used with the buffered API, you can implement
`BufferedEvent`:

```rust
pub trait BufferedEvent: Event {}
```

The event can then be used with `EventReader`/`EventWriter`:

```rust
#[derive(Event, BufferedEvent)]
struct Message(String);

fn write_hello(mut writer: EventWriter<Message>) {
    writer.write(Message("I hope these examples are alright".to_string()));
}

fn read_messages(mut reader: EventReader<Message>) {
    // Process all buffered events of type `Message`.
    for Message(message) in reader.read() {
        println!("{message}");
    }
}
```

In summary:

- Need a basic event you can trigger and observe? Derive `Event`!
- Need the event to be targeted at an entity? Derive `EntityEvent`!
- Need the event to be buffered and support the
`EventReader`/`EventWriter` API? Derive `BufferedEvent`!

## Alternatives

I'll now cover some of the alternative approaches I have considered and
briefly explored. I made this section collapsible since it ended up
being quite long :P

<details>

<summary>Expand this to see alternatives</summary>

### 1. Unified `Event` Trait

One option is not to have *three* separate traits (`Event`,
`EntityEvent`, `BufferedEvent`), and to instead just use associated
constants on `Event` to determine whether an event supports targeting
and buffering or not:

```rust
pub trait Event: Send + Sync + 'static {
    type Traversal: Traversal<Self>;
    const AUTO_PROPAGATE: bool = false;
    const TARGETED: bool = false;
    const BUFFERED: bool = false;
    
    fn register_component_id(world: &mut World) -> ComponentId { ... }
    fn component_id(world: &World) -> Option<ComponentId> { ... }
}
```

Methods can then use bounds like `where E: Event<TARGETED = true>` or
`where E: Event<BUFFERED = true>` to limit APIs to specific kinds of
events.

This would keep everything under one `Event` trait, but I don't think
it's necessarily a good idea. It makes APIs harder to read, and docs
can't easily refer to specific types of events. You can also create
weird invariants: what if you specify `TARGETED = false`, but have
`Traversal` and/or `AUTO_PROPAGATE` enabled?

### 2. `Event` and `Trigger`

Another option is to only split the traits between buffered events and
observer events, since that is the main thing people have been asking
for, and they have the largest API difference.

If we did this, I think we would need to make the terms *clearly*
separate. We can't really use `Event` and `BufferedEvent` as the names,
since it would be strange that `BufferedEvent` doesn't implement
`Event`. Something like `ObserverEvent` and `BufferedEvent` could work,
but it'd be more verbose.

For this approach, I would instead keep `Event` for the current
`EventReader`/`EventWriter` API, and call the observer event a
`Trigger`, since the "trigger" terminology is already used in the
observer context within Bevy (both as a noun and a verb). This is also
what a long [bikeshed on
Discord](https://discord.com/channels/691052431525675048/749335865876021248/1298057661878898791)
seemed to land on at the end of last year.

```rust
// For `EventReader`/`EventWriter`
pub trait Event: Send + Sync + 'static {}

// For observers
pub trait Trigger: Send + Sync + 'static {
    type Traversal: Traversal<Self>;
    const AUTO_PROPAGATE: bool = false;
    const TARGETED: bool = false;
    
    fn register_component_id(world: &mut World) -> ComponentId { ... }
    fn component_id(world: &World) -> Option<ComponentId> { ... }
}
```

The problem is that "event" is just a really good term for something
that "happens". Observers are rapidly becoming the more prominent API,
so it'd be weird to give them the `Trigger` name and leave the good
`Event` name for the less common API.

So, even though a split like this seems neat on the surface, I think it
ultimately wouldn't really work. We want to keep the `Event` name for
observer events, and there is no good alternative for the buffered
variant. (`Message` was suggested, but saying stuff like "sends a
collision message" is weird.)

### 3. `GlobalEvent` + `TargetedEvent`

What if instead of focusing on the buffered vs. observed split, we
*only* make a distinction between global and targeted events?

```rust
// A shared event trait to allow global observers to work
pub trait Event: Send + Sync + 'static {
    fn register_component_id(world: &mut World) -> ComponentId { ... }
    fn component_id(world: &World) -> Option<ComponentId> { ... }
}

// For buffered events and non-targeted observer events
pub trait GlobalEvent: Event {}

// For targeted observer events
pub trait TargetedEvent: Event {
    type Traversal: Traversal<Self>;
    const AUTO_PROPAGATE: bool = false;
}
```

This is actually the first approach I implemented, and it has the neat
characteristic that you can only use non-targeted APIs like `trigger`
with a `GlobalEvent` and targeted APIs like `trigger_targets` with a
`TargetedEvent`. You have full control over whether the entity should or
should not have a target, as they are fully distinct at the type-level.

However, there's a few problems:

- There is no type-level indication of whether a `GlobalEvent` supports
buffered events or just non-targeted observer events
- An `Event` on its own does literally nothing, it's just a shared trait
required to make global observers accept both non-targeted and targeted
events
- If an event is both a `GlobalEvent` and `TargetedEvent`, global
observers again have ambiguity on whether an event has a target or not,
undermining some of the benefits
- The names are not ideal

### 4. `Event` and `EntityEvent`

We can fix some of the problems of Alternative 3 by accepting that
targeted events can also be used in non-targeted contexts, and simply
having the `Event` and `EntityEvent` traits:

```rust
// For buffered events and non-targeted observer events
pub trait Event: Send + Sync + 'static {
    fn register_component_id(world: &mut World) -> ComponentId { ... }
    fn component_id(world: &World) -> Option<ComponentId> { ... }
}

// For targeted observer events
pub trait EntityEvent: Event {
    type Traversal: Traversal<Self>;
    const AUTO_PROPAGATE: bool = false;
}
```

This is essentially identical to this PR, just without a dedicated
`BufferedEvent`. The remaining major "problem" is that there is still
zero type-level indication of whether an `Event` event *actually*
supports the buffered API. This leads us to the solution proposed in
this PR, using `Event`, `EntityEvent`, and `BufferedEvent`.

</details>

## Conclusion

The `Event` + `EntityEvent` + `BufferedEvent` split proposed in this PR
aims to solve all the common problems with Bevy's current event model
while keeping the "weirdness" factor minimal. It splits in terms of both
the push vs. pull *and* global vs. targeted aspects, while maintaining a
shared concept for an "event".

### Why I Like This

- The term "event" remains as a single concept for all the different
kinds of events in Bevy.
- Despite all event types being "events", they use fundamentally
different APIs. Instead of assuming that you can use an event type with
any pattern (when only one is typically supported), you explicitly opt
in to each one with dedicated traits.
- Using separate traits for each type of event helps with documentation
and clearer function signatures.
- I can safely make assumptions on expected usage.
- If I see that an event is an `EntityEvent`, I can assume that I can
use `observe` on it and get targeted events.
- If I see that an event is a `BufferedEvent`, I can assume that I can
use `EventReader` to read events.
- If I see both `EntityEvent` and `BufferedEvent`, I can assume that
both APIs are supported.

In summary: This allows for a unified concept for events, while limiting
the different ways to use them with opt-in traits. No more guess-work
involved when using APIs.

### Problems?

- Because `BufferedEvent` implements `Event` (for more consistent
semantics etc.), you can still use all buffered events for non-targeted
observers. I think this is fine/good. The important part is that if you
see that an event implements `BufferedEvent`, you know that the
`EventReader`/`EventWriter` API should be supported. Whether it *also*
supports other APIs is secondary.
- I currently only support `trigger_targets` for an `EntityEvent`.
However, you can technically target components too, without targeting
any entities. I consider that such a niche and advanced use case that
it's not a huge problem to only support it for `EntityEvent`s, but we
could also split `trigger_targets` into `trigger_entities` and
`trigger_components` if we wanted to (or implement components as
entities :P).
- You can still trigger an `EntityEvent` *without* targets. I consider
this correct, since `Event` implements the non-targeted behavior, and
it'd be weird if implementing another trait *removed* behavior. However,
it does mean that global observers for entity events can technically
return `Entity::PLACEHOLDER` again (since I got rid of the
`Option<Entity>` added in #19440 for ergonomics). I think that's enough
of an edge case that it's not a huge problem, but it is worth keeping in
mind.
- ~~Deriving both `EntityEvent` and `BufferedEvent` for the same type
currently duplicates the `Event` implementation, so you instead need to
manually implement one of them.~~ Changed to always requiring `Event` to
be derived.

## Related Work

There are plans to implement multi-event support for observers,
especially for UI contexts. [Cart's
example](https://github.com/bevyengine/bevy/issues/14649#issuecomment-2960402508)
API looked like this:

```rust
// Truncated for brevity
trigger: Trigger<(
    OnAdd<Pressed>,
    OnRemove<Pressed>,
    OnAdd<InteractionDisabled>,
    OnRemove<InteractionDisabled>,
    OnInsert<Hovered>,
)>,
```

I believe this shouldn't be in conflict with this PR. If anything, this
PR might *help* achieve the multi-event pattern for entity observers
with fewer footguns: by statically enforcing that all of these events
are `EntityEvent`s in the context of `EntityCommands::observe`, we can
avoid misuse or weird cases where *some* events inside the trigger are
targeted while others are not.
2025-06-15 16:46:34 +00:00
Talin
30aa36eaf4
Core slider (#19584)
# Objective

This is part of the "core widgets" effort: #19236. 

## Solution

This PR adds the "core slider" widget to the collection.

## Testing

Tested using examples `core_widgets` and `core_widgets_observers`.

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
2025-06-15 00:53:31 +00:00
andriyDev
f47b1c00ee
Bump ron version to 0.10. (#19631)
# Objective

- Update ron to the latest version.
- This is blocking changes to AnimationGraph (as some valid structs are
not capable of being deserialized).

## Solution

- Bump ron!

## Testing

- The particular issue I was blocked by seems to be resolved!
2025-06-13 19:54:31 +00:00
Kevin Reid
ce3db843bc
Make IrradianceVolume require LightProbe (and document this). (#19621)
## Objective

Make it easier to use `IrradianceVolume` with fewer ways to silently
fail. Fix #19614.

## Solution

* Add `#[require(LightProbe)]` to `struct IrradianceVolume`.
* Document this fact.
* Also document the volume being centered on the origin by default (this
was the other thing that was unclear when getting started).

I also looked at the other implementor of `LightProbeComponent`,
`EnvironmentMapLight`, but it has a use which is *not* as a light probe,
so it should not require `LightProbe`.

## Testing

* Confirmed that `examples/3d/irradiance_volumes.rs` still works after
removing `LightProbe`.
* Reviewed generated documentation.
2025-06-13 17:09:31 +00:00
JMS55
bab31e3777
Initial raytraced lighting progress (bevy_solari) (#19058)
# Bevy Solari 
<img
src="https://github.com/user-attachments/assets/94061fc8-01cf-4208-b72a-8eecad610d76"
width="100" />

## Preface
- See release notes.
- Please talk to me in #rendering-dev on discord or open a github
discussion if you have questions about the long term plan, and keep
discussion in this PR limited to the contents of the PR :)

## Connections
- Works towards #639, #16408.
- Spawned https://github.com/bevyengine/bevy/issues/18993.
- Need to fix RT stuff in naga_oil first
https://github.com/bevyengine/naga_oil/pull/116.

## This PR

After nearly two years, I've revived the raytraced lighting effort I
first started in https://github.com/bevyengine/bevy/pull/10000.

Unlike that PR, which has realtime techniques, I've limited this PR to:
* `RaytracingScenePlugin` - BLAS and TLAS building, geometry and texture
binding, sampling functions.
* `PathtracingPlugin` - A non-realtime path tracer intended to serve as
a testbed and reference.

## What's implemented?

![image](https://github.com/user-attachments/assets/06522007-c205-46eb-8178-823f19917def)

* BLAS building on mesh load
* Emissive lights
* Directional lights with soft shadows
* Diffuse (lambert, not Bevy's diffuse BRDF) and emissive materials
* A reference path tracer with:
  * Antialiasing
  * Direct light sampling (next event estimation) with 0/1 MIS weights
  * Importance-sampled BRDF bounces
  * Russian roulette 

## What's _not_ implemented?
* Anything realtime, including a real-time denoiser
* Integration with Bevy's rasterized gbuffer
* Specular materials
* Non-opaque geometry
* Any sort of CPU or GPU optimizations
* BLAS compaction, proper bindless, and further RT APIs are things that
we need wgpu to add
* PointLights, SpotLights, or skyboxes / environment lighting 
* Support for materials other than StandardMaterial (and only a subset
of properties are supported)
* Skinned/morphed or otherwise animating/deformed meshes
* Mipmaps
* Adaptive self-intersection ray bias
* A good way for developers to detect whether the user's GPU supports RT
or not, and fallback to baked lighting.
* Documentation and actual finalized APIs (literally everything is
subject to change)

## End-user Usage
* Have a GPU that supports RT with inline ray queries
* Add `SolariPlugin` to your app
* Ensure any `Mesh` asset you want to use for raytracing has
`enable_raytracing: true` (defaults to true), and that it uses the
standard uncompressed position/normal/uv_0/tangent vertex attribute set,
triangle list topology, and 32-bit indices.
* If you don't want to build a BLAS and use the mesh for RT, set
enable_raytracing to false.
* Add the `RaytracingMesh3d` component to your entity (separate from
`Mesh3d` or `MeshletMesh3d`).

## Testing

- Did you test these changes? If so, how? 
  - Ran the solari example.
- Are there any parts that need more testing?
  - Other test scenes probably. Normal mapping would be good to test.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
  - See the solari.rs example for how to setup raytracing.
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
  - Windows 11, NVIDIA RTX 3080.

---------

Co-authored-by: atlv <email@atlasdostal.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2025-06-12 21:26:10 +00:00
Kevin Reid
1dfe83bb8d
Fix headless_renderer example and mention Screenshot. (#19598)
## Objective

- Makes `headless_renderer` example work instead of exiting without
effect.
- Guides users who actually just need
[`Screenshot`](https://docs.rs/bevy/0.16.1/bevy/render/view/window/screenshot/struct.Screenshot.html)
to use that instead.

This PR was inspired by my own efforts to do headless rendering, in
which the complexity of the `headless_renderer` example was a
distraction, and this comment from
https://github.com/bevyengine/bevy/issues/12478#issuecomment-2094925039
:

> The example added in https://github.com/bevyengine/bevy/pull/13006
would benefit from this change: be sure to clean it up when tackling
this work :)

That “cleanup” was not done, and I thought to do it, but it seems to me
that using `Screenshot` (in its current form) in the example would not
be correct, because — if I understand correctly — the example is trying
to, potentially, capture many *consecutive* frames, whereas `Screenshot`
by itself gives no means to capture multiple frames without gaps or
duplicates. But perhaps I am wrong (the code is complex and not clearly
documented), or perhaps that feature isn’t worth preserving. In that
case, let me know and I will revise this PR.

## Solution

- Added `exit_condition: bevy:🪟:ExitCondition::DontExit`
- Added a link to `Screenshot` in the crate documentation.

## Testing

- Ran the example and confirmed that it now writes an image file and
then exits.
2025-06-12 20:06:08 +00:00
Joona Aalto
e5dc177b4b
Rename Trigger to On (#19596)
# Objective

Currently, the observer API looks like this:

```rust
app.add_observer(|trigger: Trigger<Explode>| {
    info!("Entity {} exploded!", trigger.target());
});
```

Future plans for observers also include "multi-event observers" with a
trigger that looks like this (see [Cart's
example](https://github.com/bevyengine/bevy/issues/14649#issuecomment-2960402508)):

```rust
trigger: Trigger<(
    OnAdd<Pressed>,
    OnRemove<Pressed>,
    OnAdd<InteractionDisabled>,
    OnRemove<InteractionDisabled>,
    OnInsert<Hovered>,
)>,
```

In scenarios like this, there is a lot of repetition of `On`. These are
expected to be very high-traffic APIs especially in UI contexts, so
ergonomics and readability are critical.

By renaming `Trigger` to `On`, we can make these APIs read more cleanly
and get rid of the repetition:

```rust
app.add_observer(|trigger: On<Explode>| {
    info!("Entity {} exploded!", trigger.target());
});
```

```rust
trigger: On<(
    Add<Pressed>,
    Remove<Pressed>,
    Add<InteractionDisabled>,
    Remove<InteractionDisabled>,
    Insert<Hovered>,
)>,
```

Names like `On<Add<Pressed>>` emphasize the actual event listener nature
more than `Trigger<OnAdd<Pressed>>`, and look cleaner. This *also* frees
up the `Trigger` name if we want to use it for the observer event type,
splitting them out from buffered events (bikeshedding this is out of
scope for this PR though).

For prior art:
[`bevy_eventlistener`](https://github.com/aevyrie/bevy_eventlistener)
used
[`On`](https://docs.rs/bevy_eventlistener/latest/bevy_eventlistener/event_listener/struct.On.html)
for its event listener type. Though in our case, the observer is the
event listener, and `On` is just a type containing information about the
triggered event.

## Solution

Steal from `bevy_event_listener` by @aevyrie and use `On`.

- Rename `Trigger` to `On`
- Rename `OnAdd` to `Add`
- Rename `OnInsert` to `Insert`
- Rename `OnReplace` to `Replace`
- Rename `OnRemove` to `Remove`
- Rename `OnDespawn` to `Despawn`

## Discussion

### Naming Conflicts??

Using a name like `Add` might initially feel like a very bad idea, since
it risks conflict with `core::ops::Add`. However, I don't expect this to
be a big problem in practice.

- You rarely need to actually implement the `Add` trait, especially in
modules that would use the Bevy ECS.
- In the rare cases where you *do* get a conflict, it is very easy to
fix by just disambiguating, for example using `ops::Add`.
- The `Add` event is a struct while the `Add` trait is a trait (duh), so
the compiler error should be very obvious.

For the record, renaming `OnAdd` to `Add`, I got exactly *zero* errors
or conflicts within Bevy itself. But this is of course not entirely
representative of actual projects *using* Bevy.

You might then wonder, why not use `Added`? This would conflict with the
`Added` query filter, so it wouldn't work. Additionally, the current
naming convention for observer events does not use past tense.

### Documentation

This does make documentation slightly more awkward when referring to
`On` or its methods. Previous docs often referred to `Trigger::target`
or "sends a `Trigger`" (which is... a bit strange anyway), which would
now be `On::target` and "sends an observer `Event`".

You can see the diff in this PR to see some of the effects. I think it
should be fine though, we may just need to reword more documentation to
read better.
2025-06-12 18:22:33 +00:00
LP
8ab71a6999
Modified the "scroll.rs" example to use the new spawning API. (#19592)
# Objective

- Update the scroll example to use the latest API.

## Solution

- It now uses the 'children![]' API.

## Testing

- I manually verified that the scrolling was working

## Limitations
- Unfortunately, I couldn't find a way to spawn observers targeting the
entity inside the "fn() -> impl Bundle" function.
2025-06-12 02:32:18 +00:00
Al M.
0d620cdf29
Update example doc link for ImageLoaderSettings. (#19565)
Link in the "asset settings" example. The struct was moved.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: theotherphil <phil.j.ellison@gmail.com>
2025-06-11 22:43:40 +00:00
Joona Aalto
33c6f45a35
Rename some pointer events and components (#19574)
# Objective

#19366 implemented core button widgets, which included the `Depressed`
state component.

`Depressed` was chosen instead of `Pressed` to avoid conflict with the
`Pointer<Pressed>` event, but it is problematic and awkward in many
ways:

- Using the word "depressed" for such a high-traffic type is not great
due to the obvious connection to "depressed" as in depression.
- "Depressed" is not what I would search for if I was looking for a
component like this, and I'm not aware of any other engine or UI
framework using the term.
- `Depressed` is not a very natural pair to the `Pointer<Pressed>`
event.
- It might be because I'm not a native English speaker, but I have very
rarely heard someone say "a button is depressed". Seeing it, my mind
initially goes from "depression??" to "oh, de-pressed, meaning released"
and definitely not "is pressed", even though that *is* also a valid
meaning for it.

A related problem is that the current `Pointer<Pressed>` and
`Pointer<Released>` event names use a different verb tense than all of
our other observer events such as `Pointer<Click>` or
`Pointer<DragStart>`. By fixing this and renaming `Pressed` (and
`Released`), we can then use `Pressed` instead of `Depressed` for the
state component.

Additionally, the `IsHovered` and `IsDirectlyHovered` components added
in #19366 use an inconsistent naming; the other similar components don't
use an `Is` prefix. It also makes query filters like `Has<IsHovered>`
and `With<IsHovered>` a bit more awkward.

This is partially related to Cart's [picking concept
proposal](https://gist.github.com/cart/756e48a149db2838028be600defbd24a?permalink_comment_id=5598154).

## Solution

- Rename `Pointer<Pressed>` to `Pointer<Press>`
- Rename `Pointer<Released>` to `Pointer<Release>`
- Rename `Depressed` to `Pressed`
- Rename `IsHovered` to `Hovered`
- Rename `IsDirectlyHovered` to `DirectlyHovered`
2025-06-10 21:57:28 +00:00
Rob Parrett
8537718c6b
Fix pbr example text rotation (#19571)
# Objective

This example migration was missed in #16615


https://pixel-eagle.com/project/b25a040a-a980-4602-b90c-d480ab84076d/run/10633/compare/10627?screenshot=3D+Rendering/pbr.png

## Solution

Use new `UiTransform`

## Testing

`cargo run --example pbr`
2025-06-10 16:57:57 +00:00
Talin
57ddae1e93
Core button widget (#19366)
# Objective

Part of #19236

## Solution

Adds a new `bevy_core_widgets` crate containing headless widget
implementations. This PR adds a single `CoreButton` widget, more widgets
to be added later once this is approved.

## Testing

There's an example, ui/core_widgets.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-06-10 12:50:08 -04:00
Tero Laxström
c549b9e9a4
Copy stress test settings for many_camera_lights (#19512)
# Objective

- Fixes #17183

## Solution

- Copied the stress settings from the `many_animated_sprite` example
that were mentioned in the ticket

## Testing

- Run the example

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-06-10 01:12:55 +00:00
Alice Cecile
6ddd0f16a8
Component lifecycle reorganization and documentation (#19543)
# Objective

I set out with one simple goal: clearly document the differences between
each of the component lifecycle events via module docs.

Unfortunately, no such module existed: the various lifecycle code was
scattered to the wind.
Without a unified module, it's very hard to discover the related types,
and there's nowhere good to put my shiny new documentation.

## Solution

1. Unify the assorted types into a single
`bevy_ecs::component_lifecycle` module.
2. Write docs.
3. Write a migration guide.

## Testing

Thanks CI!

## Follow-up

1. The lifecycle event names are pretty confusing, especially
`OnReplace`. We should consider renaming those. No bikeshedding in my PR
though!
2. Observers need real module docs too :(
3. Any additional functional changes should be done elsewhere; this is a
simple docs and re-org PR.

---------

Co-authored-by: theotherphil <phil.j.ellison@gmail.com>
2025-06-10 00:59:16 +00:00
JMS55
bebe7c405d
Make camera controller not trigger change detection every frame (#19547)
Split off from https://github.com/bevyengine/bevy/pull/19058
2025-06-09 20:05:58 +00:00
ickshonpe
02fa833be1
Rename JustifyText to Justify (#19522)
# Objective

Rename `JustifyText`:

* The name `JustifyText` is just ugly.
* It's inconsistent since no other `bevy_text` types have a `Text-`
suffix, only prefix.
* It's inconsistent with the other text layout enum `Linebreak` which
doesn't have a prefix or suffix.

Fixes #19521.

## Solution

Rename `JustifyText` to `Justify`.

Without other context, it's natural to assume the name `Justify` refers
to text justification.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-06-09 19:59:48 +00:00
Eagster
064e5e48b4
Remove entity placeholder from observers (#19440)
# Objective

`Entity::PLACEHOLDER` acts as a magic number that will *probably* never
really exist, but it certainly could. And, `Entity` has a niche, so the
only reason to use `PLACEHOLDER` is as an alternative to `MaybeUninit`
that trades safety risks for logic risks.

As a result, bevy has generally advised against using `PLACEHOLDER`, but
we still use if for a lot internally. This pr starts removing internal
uses of it, starting from observers.

## Solution

Change all trigger target related types from `Entity` to
`Option<Entity>`

Small migration guide to come.

## Testing

CI

## Future Work

This turned a lot of code from 

```rust
trigger.target()
```

to 

```rust
trigger.target().unwrap()
```

The extra panic is no worse than before; it's just earlier than
panicking after passing the placeholder to something else.

But this is kinda annoying. 

I would like to add a `TriggerMode` or something to `Event` that would
restrict what kinds of targets can be used for that event. Many events
like `Removed` etc, are always triggered with a target. We can make
those have a way to assume Some, etc. But I wanted to save that for a
future pr.
2025-06-09 19:37:56 +00:00
ickshonpe
4836c7868c
Specialized UI transform (#16615)
# Objective

Add specialized UI transform `Component`s and fix some related problems:
* Animating UI elements by modifying the `Transform` component of UI
nodes doesn't work very well because `ui_layout_system` overwrites the
translations each frame. The `overflow_debug` example uses a horrible
hack where it copies the transform into the position that'll likely
cause a panic if any users naively copy it.
* Picking ignores rotation and scaling and assumes UI nodes are always
axis aligned.
* The clipping geometry stored in `CalculatedClip` is wrong for rotated
and scaled elements.
* Transform propagation is unnecessary for the UI, the transforms can be
updated during layout updates.
* The UI internals use both object-centered and top-left-corner-based
coordinates systems for UI nodes. Depending on the context you have to
add or subtract the half-size sometimes before transforming between
coordinate spaces. We should just use one system consistantly so that
the transform can always be directly applied.
* `Transform` doesn't support responsive coordinates.

## Solution

* Unrequire `Transform` from `Node`.
* New components `UiTransform`, `UiGlobalTransform`:
- `Node` requires `UiTransform`, `UiTransform` requires
`UiGlobalTransform`
- `UiTransform` is a 2d-only equivalent of `Transform` with a
translation in `Val`s.
- `UiGlobalTransform` newtypes `Affine2` and is updated in
`ui_layout_system`.
* New helper functions on `ComputedNode` for mapping between viewport
and local node space.
* The cursor position is transformed to local node space during picking
so that it respects rotations and scalings.
* To check if the cursor hovers a node recursively walk up the tree to
the root checking if any of the ancestor nodes clip the point at the
cursor. If the point is clipped the interaction is ignored.
* Use object-centered coordinates for UI nodes.
* `RelativeCursorPosition`'s coordinates are now object-centered with
(0,0) at the the center of the node and the corners at (±0.5, ±0.5).
* Replaced the `normalized_visible_node_rect: Rect` field of
`RelativeCursorPosition` with `cursor_over: bool`, which is set to true
when the cursor is over an unclipped point on the node. The visible area
of the node is not necessarily a rectangle, so the previous
implementation didn't work.

This should fix all the logical bugs with non-axis aligned interactions
and clipping. Rendering still needs changes but they are far outside the
scope of this PR.

Tried and abandoned two other approaches:
* New `transform` field on `Node`, require `GlobalTransform` on `Node`,
and unrequire `Transform` on `Node`. Unrequiring `Transform` opts out of
transform propagation so there is then no conflict with updating the
`GlobalTransform` in `ui_layout_system`. This was a nice change in its
simplicity but potentially confusing for users I think, all the
`GlobalTransform` docs mention `Transform` and having special rules for
how it's updated just for the UI is unpleasently surprising.
* New `transform` field on `Node`. Unrequire `Transform` on `Node`. New
`transform: Affine2` field on `ComputedNode`.
This was okay but I think most users want a separate specialized UI
transform components. The fat `ComputedNode` doesn't work well with
change detection.

Fixes #18929, #18930

## Testing

There is an example you can look at: 
```
cargo run --example ui_transform
```

Sometimes in the example if you press the rotate button couple of times
the first glyph from the top label disappears , I'm not sure what's
causing it yet but I don't think it's related to this PR.

##  Migration Guide
New specialized 2D UI transform components `UiTransform` and
`UiGlobalTransform`. `UiTransform` is a 2d-only equivalent of
`Transform` with a translation in `Val`s. `UiGlobalTransform` newtypes
`Affine2` and is updated in `ui_layout_system`.
`Node` now requires `UiTransform` instead of `Transform`. `UiTransform`
requires `UiGlobalTransform`.

In previous versions of Bevy `ui_layout_system` would overwrite UI
node's `Transform::translation` each frame. `UiTransform`s aren't
overwritten and there is no longer any need for systems that cache and
rewrite the transform for translated UI elements.

`RelativeCursorPosition`'s coordinates are now object-centered with
(0,0) at the the center of the node and the corners at (±0.5, ±0.5). Its
`normalized_visible_node_rect` field has been removed and replaced with
a new `cursor_over: bool` field which is set to true when the cursor is
hovering an unclipped area of the UI node.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-06-09 19:05:49 +00:00
SpecificProtagonist
b9754f963f
Gradients example: Fit in initial window (#19520)
# Objective

When running the `gradient` example, part of the content doesn't fit
within the initial window:
![Screenshot from 2025-06-07
11-42-59](https://github.com/user-attachments/assets/a54223db-0223-4a6e-b8e7-adb306706b28)

The UI requires 1830×930 pixels, but the initial window size is
1280×720.

## Solution

Make ui elements smaller:
![Screenshot from 2025-06-07
11-42-13](https://github.com/user-attachments/assets/c1afc01e-51be-4295-8c0f-6a983fbb0969)

Alternative: Use a larger initial window size. I decided against this
because that would make the examples less uniform, make the code less
focused on gradients and not help on web.
2025-06-08 17:26:02 +00:00
JoshValjosh
ddee5cca85
Improve Bevy's double-precision story for third-party crates (#19194)
# Objective

Certain classes of games, usually those with enormous worlds, require
some amount of support for double-precision. Libraries like `big_space`
exist to allow for large worlds while integrating cleanly with Bevy's
primarily single-precision ecosystem, but even then, games will often
still work directly in double-precision throughout the part of the
pipeline that feeds into the Bevy interface.

Currently, working with double-precision types in Bevy is a pain. `glam`
provides types like `DVec3`, but Bevy doesn't provide double-precision
analogs for `glam` wrappers like `Dir3`. This is mostly because doing so
involves one of:

- code duplication
- generics
- templates (like `glam` uses)
- macros

Each of these has issues that are enough to be deal-breakers as far as
maintainability, usability or readability. To work around this, I'm
putting together `bevy_dmath`, a crate that duplicates `bevy_math` types
and functionality to allow downstream users to enjoy the ergonomics and
power of `bevy_math` in double-precision. For the most part, it's a
smooth process, but in order to fully integrate, there are some
necessary changes that can only be made in `bevy_math`.

## Solution

This PR addresses the first and easiest issue with downstream
double-precision math support: `VectorSpace` currently can only
represent vector spaces over `f32`. This automatically closes the door
to double-precision curves, among other things. This restriction can be
easily lifted by allowing vector spaces to specify the underlying scalar
field. This PR adds a new trait `ScalarField` that satisfies the
properties of a scalar field (the ones that can be upheld statically)
and adds a new associated type `type Scalar: ScalarField` to
`VectorSpace`. It's mostly an unintrusive change. The biggest annoyances
are:

- it touches a lot of curve code
- `bevy_math::ops` doesn't support `f64`, so there are some annoying
workarounds

As far as curves code, I wanted to make this change unintrusive and
bite-sized, so I'm trying to touch as little code as possible. To prove
to myself it can be done, I went ahead and (*not* in this PR) migrated
most of the curves API to support different `ScalarField`s and it went
really smoothly! The ugliest thing was adding `P::Scalar: From<usize>`
in several places. There's an argument to be made here that we should be
using `num-traits`, but that's not immediately relevant. The point is
that for now, the smallest change I could make was to go into every
curve impl and make them generic over `VectorSpace<Scalar = f32>`.
Curves work exactly like before and don't change the user API at all.

# Follow-up

- **Extend `bevy_math::ops` to work with `f64`.** `bevy_math::ops` is
used all over, and if curves are ever going to support different
`ScalarField` types, we'll need to be able to use the correct `std` or
`libm` ops for `f64` types as well. Adding an `ops64` mod turned out to
be really ugly, but I'll point out the maintenance burden is low because
we're not going to be adding new floating-point ops anytime soon.
Another solution is to build a floating-point trait that calls the right
op variant and impl it for `f32` and `f64`. This reduces maintenance
burden because on the off chance we ever *do* want to go modify it, it's
all tied together: you can't change the interface on one without
changing the trait, which forces you to update the other. A third option
is to use `num-traits`, which is basically option 2 but someone else did
the work for us. They already support `no_std` using `libm`, so it would
be more or less a drop-in replacement. They're missing a couple
floating-point ops like `floor` and `ceil`, but we could make our own
floating-point traits for those (there's even the potential for
upstreaming them into `num-traits`).
- **Tweak curves to accept vector spaces over any `ScalarField`.**
Curves are ready to support custom scalar types as soon as the bullet
above is addressed. I will admit that the code is not as fun to look at:
`P::Scalar` instead of `f32` everywhere. We could consider an alternate
design where we use `f32` even to interpolate something like a `DVec3`,
but personally I think that's a worse solution than parameterizing
curves over the vector space's scalar type. At the end of the day, it's
not really bad to deal with in my opinion... `ScalarType` supports
enough operations that working with them is almost like working with raw
float types, and it unlocks a whole ecosystem for games that want to use
double-precision.
2025-06-08 02:02:47 +00:00
Carter Anderson
7e9d6d852b
bevyengine.org -> bevy.org (#19503)
We have acquired [bevy.org](https://bevy.org) and the migration has
finished! Meaning we can now update all of the references in this repo.
2025-06-05 23:09:28 +00:00
ZoOL
a35eed0ea4
fix: Ensure linear volume subtraction does not go below zero (#19423)
fix: [Ensure linear volume subtraction does not go below zero
](https://github.com/bevyengine/bevy/issues/19417)

## Solution
- Clamp the result of linear volume subtraction to a minimum of 0.0
- Add a new test case to verify behavior when subtracting beyond zero

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
2025-06-05 03:59:20 +00:00
François Mockers
7a7bff8c17
Hot patching systems with subsecond (#19309)
# Objective

- Enable hot patching systems with subsecond
- Fixes #19296 

## Solution

- First commit is the naive thin layer
- Second commit only check the jump table when the code is hot patched
instead of on every system execution
- Depends on https://github.com/DioxusLabs/dioxus/pull/4153 for a nicer
API, but could be done without
- Everything in second commit is feature gated, it has no impact when
the feature is not enabled

## Testing

- Check dependencies without the feature enabled: nothing dioxus in tree
- Run the new example: text and color can be changed

---------

Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2025-06-03 21:12:38 +00:00
Lucas
05e0315355
add 2d_on_ui example (#18513)
hello ! im not english native, don't hesitate to correct my code
comments.

# Objective

a simple example for new users. This is a question asked a lot, and i
struggled to do it at first too.
see https://github.com/bevyengine/bevy/discussions/11223

## Showcase


![image](https://github.com/user-attachments/assets/179ec3ad-add5-4963-ab32-3ad1cc9df15c)

---------

Co-authored-by: theotherphil <phil.j.ellison@gmail.com>
2025-06-02 22:11:32 +00:00
JMS55
8255e6cda9
Make TAA non-experimental, fixes (#18349)
The first 4 commits are designed to be reviewed independently.

- Mark TAA non-experimental now that motion vectors are written for
skinned and morphed meshes, along with skyboxes, and add it to
DefaultPlugins
- Adjust halton sequence to match what DLSS is going to use, doesn't
really affect anything, but may as well
- Make MipBias a required component on TAA instead of inserting it in
the render world
- Remove MipBias, TemporalJitter, RenderLayers, etc from the render
world if they're removed from the main world (fixes a retained render
world bug)
- Remove TAA components from the render world properly if
TemporalAntiAliasing is removed from the main world (fixes a retained
render world bug)
- extract_taa_settings() now has to query over `Option<&mut
TemporalAntiAliasing>`, which will match every single camera, in order
to cover cameras that had TemporalAntiAliasing removed this frame. This
kind of sucks, but I can't think of anything better.
- We probably have the same bug with every other rendering feature
component we have.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-06-02 16:04:08 +00:00
Daniel Skates
922ee480d2
Rename Position to UiPosition in bevy_ui (#19422)
# Objective

- Fixes #19418

## Solution

- Rename Position to UiPosition in bevy_ui

## Testing

- `cargo build`
- `cargo run --example gradients`
- `cargo run --example stacked_gradients`
2025-05-29 14:52:44 +00:00
andriyDev
c364710d1f
Fix the game of life example panicking if the pipeline shader isn't ready on the first frame. (#19420)
# Objective

- Due to recent changes related to #19024, the
`compute_shader_game_of_life` example panics on some machines especially
on Linux.
- This is due to us switching more shaders to embedded shaders - this
means the compute shader in this example takes more than one frame to
load.
- The panic in the example occurs if the shader fails to load by the
first frame (since the pipeline considers that an error).

## Solution

- Make the example do nothing if the shader isn't loaded yet. This has
the effect of waiting for the shader to load.

## Testing

- Tested the example on my Linux laptop.
2025-05-29 11:30:53 +00:00
Rob Parrett
3aaadd9b54
Minor refactoring of box_shadow example (#19404)
# Objective

Minimal effort to address feedback here:
https://github.com/bevyengine/bevy/pull/19345#discussion_r2107844018
more thoroughly.

## Solution

- Remove hardcoded label string comparisons and make more use of the new
enum added during review
- Resist temptation to let this snowball this into a huge refactor
- Maybe come back later for a few other small improvements

## Testing

`cargo run --example box_shadow`
2025-05-27 23:44:32 +00:00
Chris Berger
a8376e982e
Rename Timer::finished and Timer::paused to is_finished and is_paused (#19386)
# Objective
Renames `Timer::finished` and `Timer::paused` to `Timer::is_finished`
and `Timer::is_paused` to align the public APIs for `Time`, `Timer`, and
`Stopwatch`.

Fixes #19110
2025-05-27 22:24:18 +00:00
Rob Parrett
a575502886
Move radial_gradients example to UI testbed (#19390)
# Objective

Fixes #19385

Note: this has shader errors due to #19383 and should probably be merged
after #19384

## Solution

- Move the example to the UI testbed
- Adjust label contents and cell size so that every test case fits on
the screen
- Minor tidying, slightly less harsh colors while preserving the
intentional debug coloring

## Testing

`cargo run --example testbed_ui`

![Screenshot 2025-05-27 at 8 53
43 AM](https://github.com/user-attachments/assets/97ea20ee-d265-45f6-8b99-bcd5f6030e30)

---------

Co-authored-by: François Mockers <mockersf@gmail.com>
2025-05-27 22:06:19 +00:00
oracle58
8e585174ee
box_shadow example with adjustable settings (#19345)
# Objective

- Addresses the previous example's lack of visual appeal and clarity. It
was missing labels for clear distinction of the shadow settings used on
each of the shapes. The suggestion in the linked issue was to either
just visually update and add labels or to collapse example to a single
node with adjustable settings.
- Fixes #19240

## Solution

- Replace the previous static example with a single, central node with
adjustable settings as per issue suggestion.
- Implement button-based setting adjustments. Unfortunately slider
widgets don't seem available yet and I didn't want to further bloat the
example.
- Improve overall aesthetics of the example -- although color pallette
could still be improved. flat gray tones are probably not the best
choice as a contrast to the shadow, but the white border does help in
that aspect.
- Dynamically recolor shadows for visual clarity when increasing shadow
count.
- Add Adjustable Settings:
    - Shape selection
    - Shadow X/Y offset, blur, spread, and count
- Add Reset button to restore default settings

The disadvantage of this solution is that the old example code would
have probably been easier to digest as the new example is quite bloated
in comparison. Alternatively I could also just implement labels and fix
aesthetics of the old example without adding functionality for
adjustable settings, _but_ I personally feel like interactive examples
are more engaging to users.

## Testing

- Did you test these changes? If so, how? `cargo run --example
box_shadow` and functionality of all features of the example.
- Are there any parts that need more testing? Not that I am aware of. 
- How can other people (reviewers) test your changes? Is there anything
specific they need to know? Not really, it should be pretty
straightforward just running the new example and testing the feats.

---

## Showcase

![box-shadow-example-1](https://github.com/user-attachments/assets/57586b30-c290-4e3f-9355-5c3f6e9a6406)


![box-shadow-example-2](https://github.com/user-attachments/assets/51a51d2f-dd30-465b-b802-ddb8077adff5)

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
2025-05-27 19:43:57 +00:00
Chris Russell
571b3ba475
Remove ArchetypeComponentId and archetype_component_access (#19143)
# Objective

Remove `ArchetypeComponentId` and `archetype_component_access`.
Following #16885, they are no longer used by the engine, so we can stop
spending time calculating them or space storing them.

## Solution

Remove `ArchetypeComponentId` and everything that touches it.  

The `System::update_archetype_component_access` method no longer needs
to update `archetype_component_access`. We do still need to update query
caches, but we no longer need to do so *before* running the system. We'd
have to touch every caller anyway if we gave the method a better name,
so just remove `System::update_archetype_component_access` and
`SystemParam::new_archetype` entirely, and update the query cache in
`Query::get_param`.

The `Single` and `Populated` params also need their query caches updated
in `SystemParam::validate_param`, so change `validate_param` to take
`&mut Self::State` instead of `&Self::State`.
2025-05-27 19:04:32 +00:00
extrawurst
0a11091ea8
Adding context menu example (#19245)
# Objective

Provides usage example of a context menu

## Testing

* [x] Tested on MacOS
* [x] Tested on wasm using bevy_cli

---

## Showcase



https://github.com/user-attachments/assets/2e39cd32-131e-4535-beb7-b46680bca74a

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2025-05-26 22:27:19 +00:00
Rob Parrett
2e37783242
Move cooldown example instruction text according to example visual guidelines (#19381)
# Objective

Use the same text positioning as other examples that have instruction
text.

See
https://bevyengine.org/learn/contribute/helping-out/creating-examples/#visual-guidelines
2025-05-26 22:01:08 +00:00
François Mockers
8a223be651
Enable state scoped entities by default (#19354)
# Objective

- Enable state scoped entities by default
- Provide a way to disable it when needed

---------

Co-authored-by: Ben Frankel <ben.frankel7@gmail.com>
2025-05-26 20:26:41 +00:00
ickshonpe
f04c0ef689
tab_navigation example improvements (#19239)
# Objective

Improve the `tab_navigation` example.

## Solution

* Set different `TabIndex`s for the buttons of each group.
* Label each button with its associated `TabIndex`.
* Reduce the code duplication using a loop.

I tried to flatten it further using the new spawning APIs and
`children!` macro but not sure what the current best way to attach the
observers is.
2025-05-26 20:20:00 +00:00
theotherphil
3690ad5b0b
Remove apostrophes in possessive its (#19244)
# Objective

Fix some grammatical errors: it's -> its

Not the most useful commit in the world, but I saw a couple of these and
decided to fix the lot.

## Solution
-

## Testing
-
2025-05-26 19:53:14 +00:00
Niklas Eicker
923c2ad281
New cooldown example (#19234)
# Objective

We want to extend our examples with a new category "usage" to
demonstrate common use cases (see bevyengine/bevy-website#2131). This PR
adds an example of animated cooldowns on button clicks.

## Solution

- New example in "usage" directory
- Implement a cooldown with an animated child Node

## Testing

- I ran this on Linux
- [x] test web (with bevy CLI: `bevy run --example cooldown web --open`)

---------

Co-authored-by: Thierry Berger <contact@thierryberger.com>
Co-authored-by: Ida "Iyes" <40234599+inodentry@users.noreply.github.com>
2025-05-26 19:44:17 +00:00
Emerson Coskey
7ab00ca185
Split Camera.hdr out into a new component (#18873)
# Objective

- Simplify `Camera` initialization
- allow effects to require HDR

## Solution

- Split out `Camera.hdr` into a marker `Hdr` component

## Testing

- ran `bloom_3d` example

---

## Showcase

```rs
// before
commands.spawn((
  Camera3d
  Camera {
    hdr: true
    ..Default::default()
  }
))

// after
commands.spawn((Camera3d, Hdr));

// other rendering components can require that the camera enables hdr!
// currently implemented for Bloom, AutoExposure, and Atmosphere.
#[require(Hdr)]
pub struct Bloom;
```
2025-05-26 19:24:45 +00:00
Fallible Things
cedf8d357a
Explanation for the '2d shapes' example (#19211)
[Explanation](https://bevyengine.org/learn/contribute/helping-out/explaining-examples/)
for the 2d shapes example, taken from the original HackMD document and
edited a bit.

This example is a strange one, it's eye-catching mostly because it's the
first example (at time of writing) in the examples page. That being
said, the example does a decent amount of teaching utility to it: we can
explain the bevy math-shape to mesh pipeline, which illuminates a way of
transforming one form of data (abstract, mathematical shape
descriptions) into another (meshes) which may be novel or inspirational
to some users.

---------

Co-authored-by: theotherphil <phil.j.ellison@gmail.com>
2025-05-26 19:21:01 +00:00
Lomírus
d1f6470cc2
Fix mismatched FogFalloff (#19174)
# Objective

When user presses <kbd>3</kbd>, the falloff mode should be changed to
`ExponentialSquared` as described in the instructions, but it's not in
fact.

Online Example: https://bevyengine.org/examples-webgpu/3d-rendering/fog/

## Solution

Change it to `ExponentialSquared`

## Testing

- Did you test these changes? If so, how?

Yes, by `cargo run --example fog`

- Are there any parts that need more testing?

No.

- How can other people (reviewers) test your changes? Is there anything
specific they need to know?

```
cargo run --example fog
```

- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?

N/A
2025-05-26 17:52:27 +00:00
Weihnachtsbaum
841105a993
Add AudioSinkPlayback::position (#19173)
# Objective

- Allow users to get the playback position of playing audio.

## Solution

- Add a `position` method to `AudioSinkPlayback`
- Implement it for `AudioSink` and `SpatialAudioSink`

## Testing

- Updated `audio_control` example to show playback position
2025-05-26 17:50:40 +00:00
SpecificProtagonist
1c8d2ee3e1
viewport_node example: Remove main world image initialization (#19098)
# Objective

The new viewport example allocates a texture in main memory, even though
it's only needed on the GPU. Also fix an unnecessary warning when a
viewport's texture doesn't exist CPU-side.

## Testing

Run the `viewport_node` example.
2025-05-26 17:20:29 +00:00
robtfm
b641aa0ecf
separate border colors (#18682)
# Objective

allow specifying the left/top/right/bottom border colors separately for
ui elements

fixes #14773

## Solution

- change `BorderColor` to 
```rs
pub struct BorderColor {
    pub left: Color,
    pub top: Color,
    pub right: Color,
    pub bottom: Color,
}
```
- generate one ui node per distinct border color, set flags for the
active borders
- render only the active borders

i chose to do this rather than adding multiple colors to the
ExtractedUiNode in order to minimize the impact for the common case
where all border colors are the same.

## Testing

modified the `borders` example to use separate colors:


![image](https://github.com/user-attachments/assets/5d9a4492-429a-4ee1-9656-215511886164)

the behaviour is a bit weird but it mirrors html/css border behaviour.

---

## Migration:

To keep the existing behaviour, just change `BorderColor(color)` into
`BorderColor::all(color)`.

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
2025-05-26 16:57:13 +00:00
ickshonpe
3edacb5e46
Enable accessibility features for the button example (#18749)
# Objective

Accessibility features don't work with the UI `button` example because
`InputFocus` must be set for the accessibility systems to recognise the
button.

Fixes #18760

## Solution

* Set the button entity as the `InputFocus` when it is hovered or
pressed.
* Call `set_changed` on the `Button` component when the button's state
changes to hovered or pressed (the accessibility system's only update
the button's state when the `Button` component is marked as changed).

## Testing

Install NVDA, it should say "hover" when the button is hovered and
"pressed" when the button is pressed.

The bounds of the accessibility node are reported incorrectly. I thought
we fixed this, I'll take another look at it. It's not a problem with
this PR.
2025-05-26 15:19:55 +00:00
oracle58
d7cab93495
Add debug build option to build-wasm-example (#19312)
## Objective

- Add a `--debug` flag to `build-wasm-example` to support debug builds
for WebGL2/WebGPU targets.
- Fixes #18464

## Solution
- Added `--debug` flag to build Wasm examples in debug mode.
- Default remains release mode if `--debug` is not specified.
- Updated documentation to describe the new flag and usage.

## Testing
- Verified debug and release builds for WebGL2 and WebGPU respectively.
- Confirmed wasm artifacts are placed in the correct target dir for each
build profile:
  - Debug: `target/wasm32-unknown-unknown/debug/examples/`
  - Release: `target/wasm32-unknown-unknown/release/examples/`
- Confirmed wasm-bindgen output is written to:
`examples/wasm/target/debug` , `examples/wasm/target/release`
- Haven't actually tested running the example

| Backend | Profile | Artifacts written | Build success    |
|---------|---------|-------------------|------------------|
| webgl2 | debug | ✓ | ✓ |
| webgl2 | release | ✓ | ✓ |
| webpgu | debug | ✓ | ✓ |
| webpgu | release | ✓ | ✓ |

### Examples

**Debug**
```
$ cargo run -p build-wasm-example -- --api webgl2 --debug load_gltf
```
```
Finished `dev` profile [unoptimized + debuginfo] target(s) in 1m 02s
wasm-bindgen --out-dir examples/wasm/target/debug --out-name wasm_example --target web target/wasm32-unknown-unknown/debug/examples/load_gltf.wasm
```

**Release**
```
$ cargo run -p build-wasm-example -- --api webgl2 load_gltf`
```
```
Finished `release` profile [optimized] target(s) in 1m 08s
wasm-bindgen --out-dir examples/wasm/target/release --out-name wasm_example --target web target/wasm32-unknown-unknown/release/examples/load_gltf.wasm
```

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2025-05-24 01:43:57 +00:00
DaoLendaye
cf3f26f10b
Add GltfMeshName component and Deref implementations (#19331)
Stores mesh names from glTF files in GltfMeshName component rather than
Name component, making both GltfMeshName and GltfMaterialName behave
like strings via Deref.

# Objective

Fixed the side effects of #19287
Fixes Examples that modify gltf materials are broken #19322

## Solution

Add GltfMeshName component and Deref implementations

Stores mesh names from glTF files in GltfMeshName component rather than
Name component, making both GltfMeshName and GltfMaterialName behave
like strings via Deref.


## Testing

cargo run --example depth_of_field
cargo run --example lightmaps
cargo run --example mixed_lighting
They are consistent with the situation before the error occurred.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
2025-05-23 20:56:48 +00:00
Lucas Franca
d3012df755
Expose LogDiagnosticsState (#19323)
# Objective

Closes #19175 
Make `LogDiagnosticsState` public to be able to edit its filters

## Solution

Make `LogDiagnosticsState` public and add methods to allow editing the
duration and filter

## Testing

`cargo run -p ci`

## Showcase

Updated `log_diagnostics` example

![image](https://github.com/user-attachments/assets/25bc00f3-40e2-4b4a-b90b-137cc1f307a5)
2025-05-23 20:56:36 +00:00
ickshonpe
2b59ab8e2d
Fix Anchor component inconsistancies (#18393)
## Objective

Fix the misleading 2d anchor API where `Anchor` is a component and
required by `Text2d` but is stored on a field for sprites.

Fixes #18367

## Solution

Remove the `anchor` field from `Sprite` and require `Anchor` instead.

## Migration Guide

The `anchor` field has been removed from `Sprite`. Instead the `Anchor`
component is now a required component on `Sprite`.
2025-05-21 15:32:04 +00:00
ickshonpe
bf20c630a8
UI Node Gradients (#18139)
# Objective

Allowing drawing of UI nodes with a gradient instead of a flat color.

## Solution

The are three gradient structs corresponding to the three types of
gradients supported: `LinearGradient`, `ConicGradient` and
`RadialGradient`. These are then wrapped in a `Gradient` enum
discriminator which has `Linear`, `Conic` and `Radial` variants.

Each gradient type consists of the geometric properties for that
gradient and a list of color stops.
Color stops consist of a color, a position or angle and an optional
hint. If no position is specified for a stop, it's evenly spaced between
the previous and following stops. Color stop positions are absolute, if
you specify a list of stops:
```vec![vec![ColorStop::new(RED, Val::Percent(90.), ColorStop::new(Color::GREEN, Val::Percent(10.))```
the colors will be reordered and the gradient will transition from green at 10% to red at 90%. 

Colors are interpolated between the stops in SRGB space. The hint is a normalized value that can be used to shift the mid-point where the colors are mixed 50-50.  between the stop with the hint and the following stop.

For sharp stops with no interpolated transition, place two stops at the same position.

`ConicGradient`s and RadialGradient`s have a center which is set using the new `Position` type. `Position` consists of a normalized (relative to the UI node) `Vec2` anchor point and a responsive x, y offset.

To draw a UI node with a gradient you insert the components `BackgroundGradient` and `BorderGradient`, which both newtype a vector of `Gradient`s. If you set a background color, the background color is drawn first and the gradient(s) are drawn on top.

The implementation is deliberately simple and self contained. The shader draws the gradient in multiple passes which is quite inefficient for gradients with a very large number of color stops. It's simple though and there won't be any compatibility issues. We could make gradients a specialization for `UiPipeline` but I used a separate pipeline plugin for now to ensure that these changes don't break anything. 

#### Not supported in this PR
* Interpolation in other color spaces besides SRGB. 
* Images and text: This would need some breaking changes like a `UiColor` enum type with `Color` and `Gradient` variants, to enable `BorderColor`, `TextColor`, `BackgroundColor` and `ImageNode::color` to take either a `Color` or a gradient.
* Repeating gradients

## Testing

Includes three examples that can be used for testing:
```
cargo run --example linear_gradients
cargo run --example stacked_gradients
cargo run --example radial_gradients
```

Most of the code except the components API is contained within the `bevy_ui/src/render/linear_gradients` module.
There are no changes to any existing systems or plugins except for the addition of the gradients rendering systems to the render world schedule and the `Val` changes from #18164 . 

## Showcase

![gradients](https://github.com/user-attachments/assets/a09c5bb2-f9dc-4bc5-9d17-21a6338519d3)
![stacked](https://github.com/user-attachments/assets/7a1ad28e-8ae0-41d5-85b2-aa62647aef03)
![rad](https://github.com/user-attachments/assets/48609cf1-52aa-453c-afba-3b4845f3ddec)

Conic gradients can be used to draw simple pie charts like in CSS:
![PIE](https://github.com/user-attachments/assets/4594b96f-52ab-4974-911a-16d065d213bc)
2025-05-20 14:45:22 +00:00
SpecificProtagonist
e7e9973c80
Per world error handler (#18810)
# Objective

[see original
comment](https://github.com/bevyengine/bevy/pull/18801#issuecomment-2796981745)
> Alternately, could we store it on the World instead of a global? I
think we have a World nearby whenever we call default_error_handler().
That would avoid the need for atomics or locks, since we could do
ordinary reads and writes to the World.

Global error handlers don't actually need to be global – per world is
enough. This allows using different handlers for different worlds and
also removes the restrictions on changing the handler only once.

## Solution

Each `World` can now store its own error handler in a resource.

For convenience, you can also set the default error handler for an
`App`, which applies it to the worlds of all `SubApp`s. The old behavior
of only being able to set the error handler once is kept for apps.

We also don't need the `configurable_error_handler` feature anymore now.

## Testing

New/adjusted tests for failing schedule systems & observers.

---

## Showcase

```rust
App::new()
    .set_error_handler(info)
    …
```
2025-05-19 01:35:07 +00:00
Eagster
0b4858726c
Make entity::index non max (#18704)
# Objective

There are two problems this aims to solve. 

First, `Entity::index` is currently a `u32`. That means there are
`u32::MAX + 1` possible entities. Not only is that awkward, but it also
make `Entity` allocation more difficult. I discovered this while working
on remote entity reservation, but even on main, `Entities` doesn't
handle the `u32::MAX + 1` entity very well. It can not be batch reserved
because that iterator uses exclusive ranges, which has a maximum upper
bound of `u32::MAX - 1`. In other words, having `u32::MAX` as a valid
index can be thought of as a bug right now. We either need to make that
invalid (this PR), which makes Entity allocation cleaner and makes
remote reservation easier (because the length only needs to be u32
instead of u64, which, in atomics is a big deal), or we need to take
another pass at `Entities` to make it handle the `u32::MAX` index
properly.

Second, `TableRow`, `ArchetypeRow` and `EntityIndex` (a type alias for
u32) all have `u32` as the underlying type. That means using these as
the index type in a `SparseSet` uses 64 bits for the sparse list because
it stores `Option<IndexType>`. By using `NonMaxU32` here, we cut the
memory of that list in half. To my knowledge, `EntityIndex` is the only
thing that would really benefit from this niche. `TableRow` and
`ArchetypeRow` I think are not stored in an `Option` in bulk. But if
they ever are, this would help. Additionally this ensures
`TableRow::INVALID` and `ArchetypeRow::INVALID` never conflict with an
actual row, which in a nice bonus.

As a related note, if we do components as entities where `ComponentId`
becomes `Entity`, the the `SparseSet<ComponentId>` will see a similar
memory improvement too.

## Solution

Create a new type `EntityRow` that wraps `NonMaxU32`, similar to
`TableRow` and `ArchetypeRow`.
Change `Entity::index` to this type.

## Downsides

`NonMax` is implemented as a `NonZero` with a binary inversion. That
means accessing and storing the value takes one more instruction. I
don't think that's a big deal, but it's worth mentioning.

As a consequence, `to_bits` uses `transmute` to skip the inversion which
keeps it a nop. But that also means that ordering has now flipped. In
other words, higher indices are considered less than lower indices. I
don't think that's a problem, but it's also worth mentioning.

## Alternatives

We could keep the index as a u32 type and just document that `u32::MAX`
is invalid, modifying `Entities` to ensure it never gets handed out.
(But that's not enforced by the type system.) We could still take
advantage of the niche here in `ComponentSparseSet`. We'd just need some
unsafe manual conversions, which is probably fine, but opens up the
possibility for correctness problems later.

We could change `Entities` to fully support the `u32::MAX` index. (But
that makes `Entities` more complex and potentially slightly slower.)

## Testing

- CI
- A few tests were changed because they depend on different ordering and
`to_bits` values.

## Future Work

- It might be worth removing the niche on `Entity::generation` since
there is now a different niche.
- We could move `Entity::generation` into it's own type too for clarity.
- We should change `ComponentSparseSet` to take advantage of the new
niche. (This PR doesn't change that yet.)
- Consider removing or updating `Identifier`. This is only used for
`Entity`, so it might be worth combining since `Entity` is now more
unique.

---------

Co-authored-by: atlv <email@atlasdostal.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2025-05-07 18:20:30 +00:00
Chris Russell
9e2bd8ac18
Generic SystemParam impls for Option and Result (#18766)
# Objective

Provide a generic `impl SystemParam for Option<P>` that uses system
parameter validation. This immediately gives useful impls for params
like `EventReader` and `GizmosState` that are defined in terms of `Res`.
It also allows third-party system parameters to be usable with `Option`,
which was previously impossible due to orphan rules.

Note that this is a behavior change for `Option<Single>`. It currently
fails validation if there are multiple matching entities, but with this
change it will pass validation and produce `None`.

Also provide an impl for `Result<P, SystemParamValidationError>`. This
allows systems to inspect the error if necessary, either for bubbling it
up or for checking the `skipped` flag.

Fixes #12634
Fixes #14949
Related to #18516

## Solution

Add generic `SystemParam` impls for `Option` and `Result`, and remove
the impls for specific types.

Update documentation and `fallible_params` example with the new
semantics for `Option<Single>`.
2025-05-07 18:20:08 +00:00
Joona Aalto
7b1c9f192e
Adopt consistent FooSystems naming convention for system sets (#18900)
# Objective

Fixes a part of #14274.

Bevy has an incredibly inconsistent naming convention for its system
sets, both internally and across the ecosystem.

<img alt="System sets in Bevy"
src="https://github.com/user-attachments/assets/d16e2027-793f-4ba4-9cc9-e780b14a5a1b"
width="450" />

*Names of public system set types in Bevy*

Most Bevy types use a naming of `FooSystem` or just `Foo`, but there are
also a few `FooSystems` and `FooSet` types. In ecosystem crates on the
other hand, `FooSet` is perhaps the most commonly used name in general.
Conventions being so wildly inconsistent can make it harder for users to
pick names for their own types, to search for system sets on docs.rs, or
to even discern which types *are* system sets.

To reign in the inconsistency a bit and help unify the ecosystem, it
would be good to establish a common recommended naming convention for
system sets in Bevy itself, similar to how plugins are commonly suffixed
with `Plugin` (ex: `TimePlugin`). By adopting a consistent naming
convention in first-party Bevy, we can softly nudge ecosystem crates to
follow suit (for types where it makes sense to do so).

Choosing a naming convention is also relevant now, as the [`bevy_cli`
recently adopted
lints](https://github.com/TheBevyFlock/bevy_cli/pull/345) to enforce
naming for plugins and system sets, and the recommended naming used for
system sets is still a bit open.

## Which Name To Use?

Now the contentious part: what naming convention should we actually
adopt?

This was discussed on the Bevy Discord at the end of last year, starting
[here](<https://discord.com/channels/691052431525675048/692572690833473578/1310659954683936789>).
`FooSet` and `FooSystems` were the clear favorites, with `FooSet` very
narrowly winning an unofficial poll. However, it seems to me like the
consensus was broadly moving towards `FooSystems` at the end and after
the poll, with Cart
([source](https://discord.com/channels/691052431525675048/692572690833473578/1311140204974706708))
and later Alice
([source](https://discord.com/channels/691052431525675048/692572690833473578/1311092530732859533))
and also me being in favor of it.

Let's do a quick pros and cons list! Of course these are just what I
thought of, so take it with a grain of salt.

`FooSet`:

- Pro: Nice and short!
- Pro: Used by many ecosystem crates.
- Pro: The `Set` suffix comes directly from the trait name `SystemSet`.
- Pro: Pairs nicely with existing APIs like `in_set` and
`configure_sets`.
- Con: `Set` by itself doesn't actually indicate that it's related to
systems *at all*, apart from the implemented trait. A set of what?
- Con: Is `FooSet` a set of `Foo`s or a system set related to `Foo`? Ex:
`ContactSet`, `MeshSet`, `EnemySet`...

`FooSystems`:

- Pro: Very clearly indicates that the type represents a collection of
systems. The actual core concept, system(s), is in the name.
- Pro: Parallels nicely with `FooPlugins` for plugin groups.
- Pro: Low risk of conflicts with other names or misunderstandings about
what the type is.
- Pro: In most cases, reads *very* nicely and clearly. Ex:
`PhysicsSystems` and `AnimationSystems` as opposed to `PhysicsSet` and
`AnimationSet`.
- Pro: Easy to search for on docs.rs.
- Con: Usually results in longer names.
- Con: Not yet as widely used.

Really the big problem with `FooSet` is that it doesn't actually
describe what it is. It describes what *kind of thing* it is (a set of
something), but not *what it is a set of*, unless you know the type or
check its docs or implemented traits. `FooSystems` on the other hand is
much more self-descriptive in this regard, at the cost of being a bit
longer to type.

Ultimately, in some ways it comes down to preference and how you think
of system sets. Personally, I was originally in favor of `FooSet`, but
have been increasingly on the side of `FooSystems`, especially after
seeing what the new names would actually look like in Avian and now
Bevy. I prefer it because it usually reads better, is much more clearly
related to groups of systems than `FooSet`, and overall *feels* more
correct and natural to me in the long term.

For these reasons, and because Alice and Cart also seemed to share a
preference for it when it was previously being discussed, I propose that
we adopt a `FooSystems` naming convention where applicable.

## Solution

Rename Bevy's system set types to use a consistent `FooSet` naming where
applicable.

- `AccessibilitySystem` → `AccessibilitySystems`
- `GizmoRenderSystem` → `GizmoRenderSystems`
- `PickSet` → `PickingSystems`
- `RunFixedMainLoopSystem` → `RunFixedMainLoopSystems`
- `TransformSystem` → `TransformSystems`
- `RemoteSet` → `RemoteSystems`
- `RenderSet` → `RenderSystems`
- `SpriteSystem` → `SpriteSystems`
- `StateTransitionSteps` → `StateTransitionSystems`
- `RenderUiSystem` → `RenderUiSystems`
- `UiSystem` → `UiSystems`
- `Animation` → `AnimationSystems`
- `AssetEvents` → `AssetEventSystems`
- `TrackAssets` → `AssetTrackingSystems`
- `UpdateGizmoMeshes` → `GizmoMeshSystems`
- `InputSystem` → `InputSystems`
- `InputFocusSet` → `InputFocusSystems`
- `ExtractMaterialsSet` → `MaterialExtractionSystems`
- `ExtractMeshesSet` → `MeshExtractionSystems`
- `RumbleSystem` → `RumbleSystems`
- `CameraUpdateSystem` → `CameraUpdateSystems`
- `ExtractAssetsSet` → `AssetExtractionSystems`
- `Update2dText` → `Text2dUpdateSystems`
- `TimeSystem` → `TimeSystems`
- `AudioPlaySet` → `AudioPlaybackSystems`
- `SendEvents` → `EventSenderSystems`
- `EventUpdates` → `EventUpdateSystems`

A lot of the names got slightly longer, but they are also a lot more
consistent, and in my opinion the majority of them read much better. For
a few of the names I took the liberty of rewording things a bit;
definitely open to any further naming improvements.

There are still also cases where the `FooSystems` naming doesn't really
make sense, and those I left alone. This primarily includes system sets
like `Interned<dyn SystemSet>`, `EnterSchedules<S>`, `ExitSchedules<S>`,
or `TransitionSchedules<S>`, where the type has some special purpose and
semantics.

## Todo

- [x] Should I keep all the old names as deprecated type aliases? I can
do this, but to avoid wasting work I'd prefer to first reach consensus
on whether these renames are even desired.
- [x] Migration guide
- [x] Release notes
2025-05-06 15:18:03 +00:00
mgi388
7a1fcb7fe7
Rename StateScoped to DespawnOnExitState and add DespawnOnEnterState (#18818)
# Objective

- Alternative to and builds on top of #16284.
- Fixes #15849.

## Solution

- Rename component `StateScoped` to `DespawnOnExitState`.
- Rename system `clear_state_scoped_entities` to
`despawn_entities_on_exit_state`.
- Add `DespawnOnEnterState` and `despawn_entities_on_enter_state` which
is the `OnEnter` equivalent.

> [!NOTE]
> Compared to #16284, the main change is that I did the rename in such a
way as to keep the terms `OnExit` and `OnEnter` together. In my own
game, I was adding `VisibleOnEnterState` and `HiddenOnExitState` and
when naming those, I kept the `OnExit` and `OnEnter` together. When I
checked #16284 it stood out to me that the naming was a bit awkward.
Putting the `State` in the middle and breaking up `OnEnter` and `OnExit`
also breaks searching for those terms.

## Open questions

1. Should we split `enable_state_scoped_entities` into two functions,
one for the `OnEnter` and one for the `OnExit`? I personally have zero
need thus far for the `OnEnter` version, so I'd be interested in not
having this enabled unless I ask for it.
2. If yes to 1., should we follow my lead in my `Visibility` state
components (see below) and name these
`app.enable_despawn_entities_on_enter_state()` and
`app.enable_despawn_entities_on_exit_state()`, which IMO says what it
does on the tin?

## Testing

Ran all changed examples.

## Side note: `VisibleOnEnterState` and `HiddenOnExitState`

For reference to anyone else and to help with the open questions, I'm
including the code I wrote for controlling entity visibility when a
state is entered/exited.

<details>
<summary>visibility.rs</summary>

```rust
use bevy_app::prelude::*;
use bevy_ecs::prelude::*;
use bevy_reflect::prelude::*;
use bevy_render::prelude::*;
use bevy_state::{prelude::*, state::StateTransitionSteps};
use tracing::*;

pub trait AppExtStates {
    fn enable_visible_entities_on_enter_state<S: States>(&mut self) -> &mut Self;

    fn enable_hidden_entities_on_exit_state<S: States>(&mut self) -> &mut Self;
}

impl AppExtStates for App {
    fn enable_visible_entities_on_enter_state<S: States>(&mut self) -> &mut Self {
        self.main_mut()
            .enable_visible_entities_on_enter_state::<S>();
        self
    }

    fn enable_hidden_entities_on_exit_state<S: States>(&mut self) -> &mut Self {
        self.main_mut().enable_hidden_entities_on_exit_state::<S>();
        self
    }
}

impl AppExtStates for SubApp {
    fn enable_visible_entities_on_enter_state<S: States>(&mut self) -> &mut Self {
        if !self
            .world()
            .contains_resource::<Events<StateTransitionEvent<S>>>()
        {
            let name = core::any::type_name::<S>();
            warn!("Visible entities on enter state are enabled for state `{}`, but the state isn't installed in the app!", name);
        }
        // We work with [`StateTransition`] in set
        // [`StateTransitionSteps::ExitSchedules`] as opposed to [`OnExit`],
        // because [`OnExit`] only runs for one specific variant of the state.
        self.add_systems(
            StateTransition,
            update_to_visible_on_enter_state::<S>.in_set(StateTransitionSteps::ExitSchedules),
        )
    }

    fn enable_hidden_entities_on_exit_state<S: States>(&mut self) -> &mut Self {
        if !self
            .world()
            .contains_resource::<Events<StateTransitionEvent<S>>>()
        {
            let name = core::any::type_name::<S>();
            warn!("Hidden entities on exit state are enabled for state `{}`, but the state isn't installed in the app!", name);
        }
        // We work with [`StateTransition`] in set
        // [`StateTransitionSteps::ExitSchedules`] as opposed to [`OnExit`],
        // because [`OnExit`] only runs for one specific variant of the state.
        self.add_systems(
            StateTransition,
            update_to_hidden_on_exit_state::<S>.in_set(StateTransitionSteps::ExitSchedules),
        )
    }
}

#[derive(Clone, Component, Debug, Reflect)]
#[reflect(Component, Debug)]
pub struct VisibleOnEnterState<S: States>(pub S);

#[derive(Clone, Component, Debug, Reflect)]
#[reflect(Component, Debug)]
pub struct HiddenOnExitState<S: States>(pub S);

/// Makes entities marked with [`VisibleOnEnterState<S>`] visible when the state
/// `S` is entered.
pub fn update_to_visible_on_enter_state<S: States>(
    mut transitions: EventReader<StateTransitionEvent<S>>,
    mut query: Query<(&VisibleOnEnterState<S>, &mut Visibility)>,
) {
    // We use the latest event, because state machine internals generate at most
    // 1 transition event (per type) each frame. No event means no change
    // happened and we skip iterating all entities.
    let Some(transition) = transitions.read().last() else {
        return;
    };
    if transition.entered == transition.exited {
        return;
    }
    let Some(entered) = &transition.entered else {
        return;
    };
    for (binding, mut visibility) in query.iter_mut() {
        if binding.0 == *entered {
            visibility.set_if_neq(Visibility::Visible);
        }
    }
}

/// Makes entities marked with [`HiddenOnExitState<S>`] invisible when the state
/// `S` is exited.
pub fn update_to_hidden_on_exit_state<S: States>(
    mut transitions: EventReader<StateTransitionEvent<S>>,
    mut query: Query<(&HiddenOnExitState<S>, &mut Visibility)>,
) {
    // We use the latest event, because state machine internals generate at most
    // 1 transition event (per type) each frame. No event means no change
    // happened and we skip iterating all entities.
    let Some(transition) = transitions.read().last() else {
        return;
    };
    if transition.entered == transition.exited {
        return;
    }
    let Some(exited) = &transition.exited else {
        return;
    };
    for (binding, mut visibility) in query.iter_mut() {
        if binding.0 == *exited {
            visibility.set_if_neq(Visibility::Hidden);
        }
    }
}
```

</details>

---------

Co-authored-by: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Co-authored-by: Ben Frankel <ben.frankel7@gmail.com>
2025-05-06 00:37:04 +00:00
Jean Mertz
3b24f520b9
feat(log): support customizing default log formatting (#17722)
The LogPlugin now allows overriding the default
`tracing_subscriber::fmt::Layer` through a new `fmt_layer` option. This
enables customization of the default log output format without having to
replace the entire logging system.

For example, to disable timestamps in the log output:

```rust
fn fmt_layer(_app: &mut App) -> Option<bevy::log::BoxedFmtLayer> {
    Some(Box::new(
        bevy::log::tracing_subscriber::fmt::Layer::default()
            .without_time()
            .with_writer(std::io::stderr),
    ))
}

fn main() {
    App::new()
        .add_plugins(DefaultPlugins.set(bevy::log::LogPlugin {
            fmt_layer,
            ..default()
        }))
        .run();
}
```

This is different from the existing `custom_layer` option, because that
option _adds_ additional layers to the subscriber, but can't modify the
default formatter layer (at least, not to my knowledge).

I almost always disable timestamps in my Bevy logs, and usually also
tweak other default log formatting (such as `with_span_events`), which
made it so that I always had to disable the default logger. This allows
me to use everything the Bevy logger supports (including tracy support),
while still formatting the default logs the way I like them.

---------

Signed-off-by: Jean Mertz <git@jeanmertz.com>
2025-05-05 23:01:06 +00:00
Antony
bf42cb3532
Add a viewport UI widget (#17253)
# Objective

Add a viewport widget.

## Solution

- Add a new `ViewportNode` component to turn a UI node into a viewport.
- Add `viewport_picking` to pass pointer inputs from other pointers to
the viewport's pointer.
- Notably, this is somewhat functionally different from the viewport
widget in [the editor
prototype](https://github.com/bevyengine/bevy_editor_prototypes/pull/110/files#L124),
which just moves the pointer's location onto the render target. Viewport
widgets have their own pointers.
  - Care is taken to handle dragging in and out of viewports.
- Add `update_viewport_render_target_size` to update the viewport node's
render target's size if the node size changes.
- Feature gate picking-related viewport items behind
`bevy_ui_picking_backend`.

## Testing

I've been using an example I made to test the widget (and added it as
`viewport_node`):

<details><summary>Code</summary>

```rust
//! A simple scene to demonstrate spawning a viewport widget. The example will demonstrate how to
//! pick entities visible in the widget's view.

use bevy::picking::pointer::PointerInteraction;
use bevy::prelude::*;

use bevy::ui::widget::ViewportNode;
use bevy::{
    image::{TextureFormatPixelInfo, Volume},
    window::PrimaryWindow,
};
use bevy_render::{
    camera::RenderTarget,
    render_resource::{
        Extent3d, TextureDescriptor, TextureDimension, TextureFormat, TextureUsages,
    },
};

fn main() {
    App::new()
        .add_plugins((DefaultPlugins, MeshPickingPlugin))
        .add_systems(Startup, test)
        .add_systems(Update, draw_mesh_intersections)
        .run();
}

#[derive(Component, Reflect, Debug)]
#[reflect(Component)]
struct Shape;

fn test(
    mut commands: Commands,
    window: Query<&Window, With<PrimaryWindow>>,
    mut images: ResMut<Assets<Image>>,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
) {
    // Spawn a UI camera
    commands.spawn(Camera3d::default());

    // Set up an texture for the 3D camera to render to
    let window = window.get_single().unwrap();
    let window_size = window.physical_size();
    let size = Extent3d {
        width: window_size.x,
        height: window_size.y,
        ..default()
    };
    let format = TextureFormat::Bgra8UnormSrgb;
    let image = Image {
        data: Some(vec![0; size.volume() * format.pixel_size()]),
        texture_descriptor: TextureDescriptor {
            label: None,
            size,
            dimension: TextureDimension::D2,
            format,
            mip_level_count: 1,
            sample_count: 1,
            usage: TextureUsages::TEXTURE_BINDING
                | TextureUsages::COPY_DST
                | TextureUsages::RENDER_ATTACHMENT,
            view_formats: &[],
        },
        ..default()
    };
    let image_handle = images.add(image);

    // Spawn the 3D camera
    let camera = commands
        .spawn((
            Camera3d::default(),
            Camera {
                // Render this camera before our UI camera
                order: -1,
                target: RenderTarget::Image(image_handle.clone().into()),
                ..default()
            },
        ))
        .id();

    // Spawn something for the 3D camera to look at
    commands
        .spawn((
            Mesh3d(meshes.add(Cuboid::new(5.0, 5.0, 5.0))),
            MeshMaterial3d(materials.add(Color::WHITE)),
            Transform::from_xyz(0.0, 0.0, -10.0),
            Shape,
        ))
        // We can observe pointer events on our objects as normal, the
        // `bevy::ui::widgets::viewport_picking` system will take care of ensuring our viewport
        // clicks pass through
        .observe(on_drag_cuboid);

    // Spawn our viewport widget
    commands
        .spawn((
            Node {
                position_type: PositionType::Absolute,
                top: Val::Px(50.0),
                left: Val::Px(50.0),
                width: Val::Px(200.0),
                height: Val::Px(200.0),
                border: UiRect::all(Val::Px(5.0)),
                ..default()
            },
            BorderColor(Color::WHITE),
            ViewportNode::new(camera),
        ))
        .observe(on_drag_viewport);
}

fn on_drag_viewport(drag: Trigger<Pointer<Drag>>, mut node_query: Query<&mut Node>) {
    if matches!(drag.button, PointerButton::Secondary) {
        let mut node = node_query.get_mut(drag.target()).unwrap();

        if let (Val::Px(top), Val::Px(left)) = (node.top, node.left) {
            node.left = Val::Px(left + drag.delta.x);
            node.top = Val::Px(top + drag.delta.y);
        };
    }
}

fn on_drag_cuboid(drag: Trigger<Pointer<Drag>>, mut transform_query: Query<&mut Transform>) {
    if matches!(drag.button, PointerButton::Primary) {
        let mut transform = transform_query.get_mut(drag.target()).unwrap();
        transform.rotate_y(drag.delta.x * 0.02);
        transform.rotate_x(drag.delta.y * 0.02);
    }
}

fn draw_mesh_intersections(
    pointers: Query<&PointerInteraction>,
    untargetable: Query<Entity, Without<Shape>>,
    mut gizmos: Gizmos,
) {
    for (point, normal) in pointers
        .iter()
        .flat_map(|interaction| interaction.iter())
        .filter_map(|(entity, hit)| {
            if !untargetable.contains(*entity) {
                hit.position.zip(hit.normal)
            } else {
                None
            }
        })
    {
        gizmos.arrow(point, point + normal.normalize() * 0.5, Color::WHITE);
    }
}
```

</details>

## Showcase


https://github.com/user-attachments/assets/39f44eac-2c2a-4fd9-a606-04171f806dc1

## Open Questions

- <del>Not sure whether the entire widget should be feature gated behind
`bevy_ui_picking_backend` or not? I chose a partial approach since maybe
someone will want to use the widget without any picking being
involved.</del>
- <del>Is `PickSet::Last` the expected set for `viewport_picking`?
Perhaps `PickSet::Input` is more suited.</del>
- <del>Can `dragged_last_frame` be removed in favor of a better dragging
check? Another option that comes to mind is reading `Drag` and `DragEnd`
events, but this seems messier.</del>

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2025-05-05 22:57:37 +00:00
Greeble
235257ff62
Fix occlusion culling not respecting device limits (#18974)
The occlusion culling plugin checks for a GPU feature by looking at
`RenderAdapter`. This is wrong - it should be checking `RenderDevice`.
See these notes for background:
https://github.com/bevyengine/bevy/discussions/18973

I don't have any evidence that this was causing any bugs, so right now
it's just a precaution.

## Testing

```
cargo run --example occlusion_culling
```

Tested on Win10/Nvidia across Vulkan, WebGL/Chrome, WebGPU/Chrome.
2025-05-05 18:04:43 +00:00
akimakinai
0f6d532a15
Sprite picking docs fix (#19016)
# Objective

- Docs in sprite picking plugin / example contain outdated information.

References:
- Sprite picking now always require `Picking` - #17842
- Transparency pass-through added - #16388

## Solution

- Fix the docs.
2025-05-05 17:45:14 +00:00
Marius Cobzarenco
20b2b5e6b1
Fix tonemapping example when using a local image (#19061)
# Objective

- The tonemapping example allows using a local image to try out
different color grading. However, using a local file stopped working
when we added the `UnapprovedPathMode` setting to the assets plugin.

## Solution

- Set `unapproved_path_mode: UnapprovedPathMode::Allow` in the example

## Testing

- I tried out the example with local images, previously it would fail
saying it's an untrusted path.
2025-05-05 17:39:32 +00:00
Chris Biscardi
56405890f2
refactor ui/borders example to use new children! macro (#18962)
# Objective

Refactor
[`examples/ui/borders.rs`](7f0490655c/examples/ui/borders.rs)
to use the new spawning/hierarchy APIs in 0.16.

## Solution

This refactor reduces the number of `.spawn` calls from about 16 to 2,
using one spawn for each major feature:

* camera2d
* ui layout

The `Children::spawn` relationship API is used to take advantage of
`SpawnIter` for the borders examples in each block.

Each block of examples now returns a Bundle into its respective
variable, which is then used in combination with the new `label` widget
which makes use of the new `impl Bundle` return capability. This allows
the ui layout to use a single `.spawn` with the `children!` macro.

The blocks of examples are still in separate variables because it felt
like a useful way to organize it still, even without needing to spawn at
those locations.

Functionality of the demo hasn't changed, this is just an API/code
update.

## Showcase

![screenshot-2025-04-27-at-18 05
19@2x](https://github.com/user-attachments/assets/5f10b28b-b0f1-4a55-af9f-2e7b05b7b4bf)

<details>
<summary>Before screenshot</summary>

![screenshot-2025-04-27-at-18 17
12@2x](https://github.com/user-attachments/assets/ae159d96-ba4d-4429-b934-7779470c480a)

</details>

---------

Co-authored-by: François Mockers <mockersf@gmail.com>
2025-05-04 08:35:03 +00:00
ickshonpe
5e2ecf4178
Text background colors (#18892)
# Objective

Add background colors for text.

Fixes #18889

## Solution

New component `TextBackgroundColor`, add it to any UI `Text` or
`TextSpan` entity to add a background color to its text.
New field on `TextLayoutInfo` `section_rects` holds the list of bounding
rects for each text section.

The bounding rects are generated in `TextPipeline::queue_text` during
text layout, `extract_text_background_colors` extracts the colored
background rects for rendering.

Didn't include `Text2d` support because of z-order issues.

The section rects can also be used to implement interactions targeting
individual text sections.

## Testing
Includes a basic example that can be used for testing:
```
cargo run --example text_background_colors
```
---

## Showcase


![tbcm](https://github.com/user-attachments/assets/e584e197-1a8c-4248-82ab-2461d904a85b)

Using a proportional font with kerning the results aren't so tidy (since
the bounds of adjacent glyphs can overlap) but it still works fine:


![tbc](https://github.com/user-attachments/assets/788bb052-4216-4019-a594-7c1b41164dd5)

---------

Co-authored-by: Olle Lukowski <lukowskiolle@gmail.com>
Co-authored-by: Gilles Henaux <ghx_github_priv@fastmail.com>
2025-05-04 08:18:46 +00:00
Peter S.
cd67bac544
Expose deferred screen edges setting for ios devices (#18729)
# Objective

- This just exposes the preferred [screen edges deferring system
gestures](https://developer.apple.com/documentation/uikit/uiviewcontroller/preferredscreenedgesdeferringsystemgestures)
setting from
[winit](https://docs.rs/winit/latest/winit/platform/ios/trait.WindowExtIOS.html#tymethod.set_preferred_screen_edges_deferring_system_gestures),
making it accessible in bevy apps.

This setting is useful for ios apps that make use of the screen edges,
letting the app have control of the first edge gesture before relegating
to the os.


## Testing

- Tested on simulator and on an iPhone Xs

---

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Greeble <166992735+greeble-dev@users.noreply.github.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2025-04-30 21:24:53 +00:00
Rob Parrett
b40845d296
Fix a few subcrate import paths in examples (#19002)
# Objective

Tripped over the `directional_navigation` one recently while playing
around with that example.

Examples should import items from `bevy` rather than the sub-crates
directly.

## Solution

Use paths re-exported by `bevy`.

## Testing

```
cargo run --example log_diagnostics
cargo run --example directional_navigation
cargo run --example custom_projection
```
2025-04-30 18:41:17 +00:00
Raul Rabadan Arroyo
c4408a817b
Make the example android app explicitly handle some device config change events to avoid getting the activity destroyed (#18839)
# Objective

Fixes #18316

## Solution

Add android:configChanges="orientation|screenSize" to the
AndroidManifest.xml as indicated in https://stackoverflow.com/a/3329486
to avoid the GameActivity from getting destroyed, making the app
stuck/crash.

## Testing

I checked the results in my phone and after adding the config change the
issue went away. The change is relatively trivial, so there shouldn't be
the need to make a lot more testing.
2025-04-26 21:21:50 +00:00
Patrick Walton
5e69518f10
Don't restrict the scene viewer to loading assets from approved paths. (#18828)
The purpose of the scene viewer is to load arbitrary glTF scenes, so
it's inconvenient if they have to be moved into the Bevy assets
directory first. Thus this patch switches the scene viewer to use
`UnapprovedPathMode::Allow`.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2025-04-14 20:19:37 +00:00
Carter Anderson
e9a0ef49f9
Rename bevy_platform_support to bevy_platform (#18813)
# Objective

The goal of `bevy_platform_support` is to provide a set of platform
agnostic APIs, alongside platform-specific functionality. This is a high
traffic crate (providing things like HashMap and Instant). Especially in
light of https://github.com/bevyengine/bevy/discussions/18799, it
deserves a friendlier / shorter name.

Given that it hasn't had a full release yet, getting this change in
before Bevy 0.16 makes sense.

## Solution

- Rename `bevy_platform_support` to `bevy_platform`.
2025-04-11 23:13:28 +00:00
charlotte
e799625ea5
Add binned 2d/3d Wireframe render phase (#18587)
# Objective

Fixes #16896
Fixes #17737

## Solution

Adds a new render phase, including all the new cold specialization
patterns, for wireframes. There's a *lot* of regrettable duplication
here between 3d/2d.

## Testing

All the examples.

## Migration Guide
- `WireframePlugin` must now be created with
`WireframePlugin::default()`.
2025-04-09 21:34:53 +00:00
Patrick Walton
dc7c8f228f
Add bindless support back to ExtendedMaterial. (#18025)
PR #17898 disabled bindless support for `ExtendedMaterial`. This commit
adds it back. It also adds a new example, `extended_material_bindless`,
showing how to use it.
2025-04-09 15:34:44 +00:00
Freyja-moth
714b4a43d6
Change with_related to work with a Bundle and added with_relationships method (#18699)
# Objective

Fixes #18678

## Solution

Moved the current `with_related` method to `with_relationships` and
added a new `with_related` that uses a bundle.

I'm not entirely sold on the name just yet, if anyone has any ideas let
me know.

## Testing

I wasn't able to test these changes because it crashed my computer every
time I tried (fun). But there don't seem to be any tests that use the
old `with_related` method so it should be fine, hopefully

## Showcase

```rust
commands.spawn_empty()
    .with_related::<Relationship>(Name::new("Related thingy"))
    .with_relationships(|rel| {
        rel.spawn(Name::new("Second related thingy"));
    });
```

---------

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2025-04-09 02:34:49 +00:00
Greeble
a1fd3a4c69
Remove WebGL padding from MotionBlur (#18727)
## Objective

The `MotionBlur` component exposes renderer internals. Users shouldn't
have to deal with this.

```rust
MotionBlur {
    shutter_angle: 1.0,
    samples: 2,
    #[cfg(all(feature = "webgl2", target_arch = "wasm32", not(feature = "webgpu")))]
    _webgl2_padding: Default::default(),
},
```

## Solution

The renderer now uses a separate `MotionBlurUniform` struct for its
internals. `MotionBlur` no longer needs padding.

I was a bit unsure about the name `MotionBlurUniform`. Other modules use
a mix of `Uniform` and `Uniforms`.

## Testing

```
cargo run --example motion_blur
```

Tested on Win10/Nvidia across Vulkan, WebGL/Chrome, WebGPU/Chrome.
2025-04-06 20:00:59 +00:00
ZoOL
06f9e5eca5
fix typo (#18696)
# Objective

- fix some typo

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-04-03 17:18:09 +00:00
Kristoffer Søholm
86fa2ac570
Fix issues in log_diagnostics example (#18652)
# Objective

Adopts / builds on top of #18435.

The `log_diagnostics` example has bit-rotted and accumulated multiple
issues:
- It didn't explain the ordering constraint on DefaultPlugins, as noted
by the original PR
- Apparently `AssetCountDiagnosticsPlugin` no longer exists (?!). I
couldn't figure out when or why it was removed, maybe it got missed in
Assets v2?
- The comments didn't explain what kind of info you get by the various
plugins, making you do work to figure it out
- ~As far as I can tell `RenderDiagnosticsPlugin` currently doesn't
register any diagnostics in the traditional sense, but is only focused
on rendering spans? At least it doesn't print anything extra when added
for me, so having it here is misleading.~ It didn't print anything
because there was nothing to render in this example

## Solution

- Make all plugins be commented in to prevent further bit-rot
- Remove reference to the missing plugin
- Add extra comments describing the diagnostics in more detail
- Add something to render so we get render diagnostics

## Testing

Run the example, see relevant diagnostics printed out
2025-04-02 16:59:50 +00:00
Carter Anderson
d8fa57bd7b
Switch ChildOf back to tuple struct (#18672)
# Objective

In #17905 we swapped to a named field on `ChildOf` to help resolve
variable naming ambiguity of child vs parent (ex: `child_of.parent`
clearly reads as "I am accessing the parent of the child_of
relationship", whereas `child_of.0` is less clear).

Unfortunately this has the side effect of making initialization less
ideal. `ChildOf { parent }` reads just as well as `ChildOf(parent)`, but
`ChildOf { parent: root }` doesn't read nearly as well as
`ChildOf(root)`.

## Solution

Move back to `ChildOf(pub Entity)` but add a `child_of.parent()`
function and use it for all accesses. The downside here is that users
are no longer "forced" to access the parent field with `parent`
nomenclature, but I think this strikes the right balance.

Take a look at the diff. I think the results provide strong evidence for
this change. Initialization has the benefit of reading much better _and_
of taking up significantly less space, as many lines go from 3 to 1, and
we're cutting out a bunch of syntax in some cases.

Sadly I do think this should land in 0.16 as the cost of doing this
_after_ the relationships migration is high.
2025-04-02 00:10:10 +00:00
Chris Russell
b4614dadcd
Use Display instead of Debug in the default error handler (#18629)
# Objective

Improve error messages for missing resources.  

The default error handler currently prints the `Debug` representation of
the error type instead of `Display`. Most error types use
`#[derive(Debug)]`, resulting in a dump of the structure, but will have
a user-friendly message for `Display`.

Follow-up to #18593

## Solution

Change the default error handler to use `Display` instead of `Debug`.  

Change `BevyError` to include the backtrace in the `Display` format in
addition to `Debug` so that it is still included.

## Showcase

Before: 

```
Encountered an error in system `system_name`: SystemParamValidationError { skipped: false, message: "Resource does not exist", param: "bevy_ecs::change_detection::Res<app_name::ResourceType>" }

Encountered an error in system `other_system_name`: "String message with\nmultiple lines."
```

After

```
Encountered an error in system `system_name`: Parameter `Res<ResourceType>` failed validation: Resource does not exist

Encountered an error in system `other_system_name`: String message with
multiple lines.
```
2025-03-31 18:28:19 +00:00
Vic
f57c7a43c4
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 03:51:14 +00:00
François Mockers
3945a6de3b
Fix wesl in wasm and webgl2 (#18591)
# Objective

- feature `shader_format_wesl` doesn't compile in Wasm
- once fixed, example `shader_material_wesl` doesn't work in WebGL2

## Solution

- remove special path handling when loading shaders. this seems like a
way to escape the asset folder which we don't want to allow, and can't
compile on android or wasm, and can't work on iOS (filesystem is rooted
there)
- pad material so that it's 16 bits. I couldn't get conditional
compilation to work in wesl for type declaration, it fails to parse
- the shader renders the color `(0.0, 0.0, 0.0, 0.0)` when it's not a
polka dot. this renders as black on WebGPU/metal/..., and white on
WebGL2. change it to `(0.0, 0.0, 0.0, 1.0)` so that it's black
everywhere
2025-03-28 21:45:02 +00:00
andriyDev
a08760b19b
Revert PR #15481 to resolve a regression. (#18567)
# Objective

- Fixes #18010.

## Solution

- Revert the offending PRs! These are #15481 and #18013. We now no
longer get an error if there are duplicate subassets.
- In theory we could untangle #18013 from #15481, but that may be
tricky, and may still introduce regressions. To avoid this worry (since
we're already in RC mode), I am just reverting both.

## Testing

- This is just a revert.

---

## Migration Guide

<Remove the migration guides for #15481 and #18013>

I will make a PR to the bevy_website repo after this is merged.
2025-03-27 21:32:01 +00:00
François Mockers
7a8dfdaec2
don't include file not available on docs.rs (#18551)
# Objective

- Fixes #18539 
- Doc failed to build as an example `include_str!` an asset, but assets
are not available in the packaged crate

## Solution

- Don't `include_str!` the shader but read it at runtime
2025-03-26 06:07:39 +00:00
Chris Russell
837991a5b5
Replace ValidationOutcome with Result (#18541)
# Objective

Make it easier to short-circuit system parameter validation.  

Simplify the API surface by combining `ValidationOutcome` with
`SystemParamValidationError`.

## Solution

Replace `ValidationOutcome` with `Result<(),
SystemParamValidationError>`. Move the docs from `ValidationOutcome` to
`SystemParamValidationError`.

Add a `skipped` field to `SystemParamValidationError` to distinguish the
`Skipped` and `Invalid` variants.

Use the `?` operator to short-circuit validation in tuples of system
params.
2025-03-26 03:36:16 +00:00
ickshonpe
f74abb1b89
Add sprite flipping to testbed_2d's sprite scene (#18537)
# Objective

Add sprite flipping to `testbed_2d`'s sprite scene

## Solution

Draw the sprite flipped in each axis and both axes.

Changed the sprite to the rectangular bevy banner with text and made the
images different colors.

## Testing
```
cargo run --example testbed_2d
```


![image](https://github.com/user-attachments/assets/dcfe687b-2f40-4417-bb20-6c892b425228)

---------

Co-authored-by: François Mockers <mockersf@gmail.com>
2025-03-25 21:14:17 +00:00
Alice Cecile
6a981aaa6f
Define system param validation on a per-system parameter basis (#18504)
# Objective

When introduced, `Single` was intended to simply be silently skipped,
allowing for graceful and efficient handling of systems during invalid
game states (such as when the player is dead).

However, this also caused missing resources to *also* be silently
skipped, leading to confusing and very hard to debug failures. In
0.15.1, this behavior was reverted to a panic, making missing resources
easier to debug, but largely making `Single` (and `Populated`)
worthless, as they would panic during expected game states.

Ultimately, the consensus is that this behavior should differ on a
per-system-param basis. However, there was no sensible way to *do* that
before this PR.

## Solution

Swap `SystemParam::validate_param` from a `bool` to:

```rust
/// The outcome of system / system param validation,
/// used by system executors to determine what to do with a system.
pub enum ValidationOutcome {
    /// All system parameters were validated successfully and the system can be run.
    Valid,
    /// At least one system parameter failed validation, and an error must be handled.
    /// By default, this will result in1 a panic. See [crate::error] for more information.
    ///
    /// This is the default behavior, and is suitable for system params that should *always* be valid,
    /// either because sensible fallback behavior exists (like [`Query`] or because
    /// failures in validation should be considered a bug in the user's logic that must be immediately addressed (like [`Res`]).
    Invalid,
    /// At least one system parameter failed validation, but the system should be skipped due to [`ValidationBehavior::Skip`].
    /// This is suitable for system params that are intended to only operate in certain application states, such as [`Single`].
    Skipped,
}
```
Then, inside of each `SystemParam` implementation, return either Valid,
Invalid or Skipped.

Currently, only `Single`, `Option<Single>` and `Populated` use the
`Skipped` behavior. Other params (like resources) retain their current
failing

## Testing

Messed around with the fallible_params example. Added a pair of tests:
one for panicking when resources are missing, and another for properly
skipping `Single` and `Populated` system params.

## To do

- [x] get https://github.com/bevyengine/bevy/pull/18454 merged
- [x] fix the todo!() in the macro-powered tuple implementation (please
help 🥺)
- [x] test
- [x] write a migration guide
- [x] update the example comments

## Migration Guide

Various system and system parameter validation methods
(`SystemParam::validate_param`, `System::validate_param` and
`System::validate_param_unsafe`) now return and accept a
`ValidationOutcome` enum, rather than a `bool`. The previous `true`
values map to `ValidationOutcome::Valid`, while `false` maps to
`ValidationOutcome::Invalid`.

However, if you wrote a custom schedule executor, you should now respect
the new `ValidationOutcome::Skipped` parameter, skipping any systems
whose validation was skipped. By contrast, `ValidationOutcome::Invalid`
systems should also be skipped, but you should call the
`default_error_handler` on them first, which by default will result in a
panic.

If you are implementing a custom `SystemParam`, you should consider
whether failing system param validation is an error or an expected
state, and choose between `Invalid` and `Skipped` accordingly. In Bevy
itself, `Single` and `Populated` now once again skip the system when
their conditions are not met. This is the 0.15.0 behavior, but stands in
contrast to the 0.15.1 behavior, where they would panic.

---------

Co-authored-by: MiniaczQ <xnetroidpl@gmail.com>
Co-authored-by: Dmytro Banin <banind@cs.washington.edu>
Co-authored-by: Chris Russell <8494645+chescock@users.noreply.github.com>
2025-03-25 04:27:20 +00:00
Alice Cecile
ce7d4e41d6
Make system param validation rely on the unified ECS error handling via the GLOBAL_ERROR_HANDLER (#18454)
# Objective

There are two related problems here:

1. Users should be able to change the fallback behavior of *all*
ECS-based errors in their application by setting the
`GLOBAL_ERROR_HANDLER`. See #18351 for earlier work in this vein.
2. The existing solution (#15500) for customizing this behavior is high
on boilerplate, not global and adds a great deal of complexity.

The consensus is that the default behavior when a parameter fails
validation should be set based on the kind of system parameter in
question: `Single` / `Populated` should silently skip the system, but
`Res` should panic. Setting this behavior at the system level is a
bandaid that makes getting to that ideal behavior more painful, and can
mask real failures (if a resource is missing but you've ignored a system
to make the Single stop panicking you're going to have a bad day).

## Solution

I've removed the existing `ParamWarnPolicy`-based configuration, and
wired up the `GLOBAL_ERROR_HANDLER`/`default_error_handler` to the
various schedule executors to properly plumb through errors .

Additionally, I've done a small cleanup pass on the corresponding
example.

## Testing

I've run the `fallible_params` example, with both the default and a
custom global error handler. The former panics (as expected), and the
latter spams the error console with warnings 🥲

## Questions for reviewers

1. Currently, failed system param validation will result in endless
console spam. Do you want me to implement a solution for warn_once-style
debouncing somehow?
2. Currently, the error reporting for failed system param validation is
very limited: all we get is that a system param failed validation and
the name of the system. Do you want me to implement improved error
reporting by bubbling up errors in this PR?
3. There is broad consensus that the default behavior for failed system
param validation should be set on a per-system param basis. Would you
like me to implement that in this PR?

My gut instinct is that we absolutely want to solve 2 and 3, but it will
be much easier to do that work (and review it) if we split the PRs
apart.

## Migration Guide

`ParamWarnPolicy` and the `WithParamWarnPolicy` have been removed
completely. Failures during system param validation are now handled via
the `GLOBAL_ERROR_HANDLER`: please see the `bevy_ecs::error` module docs
for more information.

---------

Co-authored-by: MiniaczQ <xnetroidpl@gmail.com>
2025-03-24 05:58:05 +00:00
Sung-jin Brian Hong
694db96ab8
Fix compile errors on headless example (#18497)
# Objective

- Fixes compile errors on headless example when running `cargo run
--example headless --no-default-features`

```
error[E0432]: unresolved import `bevy::log`
  --> examples/app/headless.rs:13:39
   |
13 | use bevy::{app::ScheduleRunnerPlugin, log::LogPlugin, prelude::*};
   |                                       ^^^ could not find `log` in `bevy`

For more information about this error, try `rustc --explain E0432`.
error: could not compile `bevy` (example "headless") due to 1 previous error
```

## Solution

- Since commit cc69fdd bevy_log has been identified as a separate
feature, thus requiring additional parameters to build headless example.
- Changed the command to run to: `cargo run --example headless
--no-default-features --features bevy_log`

## Testing

- The new command successfully builds the example
2025-03-23 21:24:20 +00:00
krunchington
a090e2fd47
Update shader_prepass, testbed_2d, and first_person_view_model examples to use children! macro (#18270)
# Objective

Contributes to #18238 
Updates the `shader_prepass`, `testbed_2d` and `first_person_view_model`
examples to use the `children!` macro. I wanted to keep the PR small but
chose to do 3 examples since they were all limited in scope

## Solution

Updates examples to use the Improved Spawning API merged in
https://github.com/bevyengine/bevy/pull/17521

## Testing

- Did you test these changes? If so, how?
- Opened the examples before and after and verified the same behavior
was observed. I did this on Ubuntu 24.04.2 LTS using `--features
wayland`.
- Are there any parts that need more testing?
- Other OS's and features can't hurt, but this is such a small change it
shouldn't be a problem.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
  - Run the examples yourself with and without these changes.
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
  - see above

---

## Showcase

n/a

## Migration Guide

n/a
2025-03-22 22:35:20 +00:00
krunchington
5a9cb7de3e
Update text2d example to use children macro (#18317)
# Objective

Contributes to #18238 
Updates the `text2d`, example to use the `children!` macro.

I'm not sure I love the SpawnIter usage here, as I feel the `move`
keyword in this case is subtle and error prone for those who lose fights
with the borrow checker frequently (like me). Feedback very much
welcome.

## Solution

Updates examples to use the Improved Spawning API merged in
https://github.com/bevyengine/bevy/pull/17521

## Testing

- Did you test these changes? If so, how?
- Opened the examples before and after and verified the same behavior
was observed. I did this on Ubuntu 24.04.2 LTS using `--features
wayland`.
- Are there any parts that need more testing?
- Other OS's and features can't hurt, but this is such a small change it
shouldn't be a problem.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
  - Run the examples yourself with and without these changes.
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
  - see above

---

## Showcase

n/a

## Migration Guide

n/a
2025-03-22 22:32:40 +00:00
ickshonpe
84b09b9398
Newtype Anchor (#18439)
# Objective

The `Anchor` component doesn't need to be a enum. The variants are just
mapped to `Vec2`s so it could be changed to a newtype with associated
const values, saving the space needed for the discriminator by the enum.

Also there was no benefit I think in hiding the underlying `Vec2`
representation of `Anchor`s.

Suggested by @atlv24.

Fixes #18459
Fixes #18460

## Solution

Change `Anchor` to a struct newtyping a `Vec2`, and its variants into
associated constants.

## Migration Guide

The anchor component has been changed from an enum to a struct newtyping
a `Vec2`. The `Custom` variant has been removed, instead to construct a
custom `Anchor` use its tuple constructor:
```rust
Sprite {
     anchor: Anchor(Vec2::new(0.25, 0.4)),
     ..default()
}
```
The other enum variants have been replaced with corresponding constants:
* `Anchor::BottomLeft` to `Anchor::BOTTOM_LEFT`
* `Anchor::Center` to `Anchor::CENTER`
* `Anchor::TopRight` to `Anchor::TOP_RIGHT`
* .. and so on for the remaining variants
2025-03-21 22:27:11 +00:00
krunchington
9ae7aa4399
Update testbed_ui to use Improved Spawning API (#18329)
# Objective

Contributes to #18238 
Updates the `text2d`, example to use the `children!` macro.

~~The SpawnIter usage in this example is maybe not the best. Very open
to opinions. I even left one `with_children` that I thought was just
much better than any alternative.~~

## Solution

Updates examples to use the Improved Spawning API merged in
https://github.com/bevyengine/bevy/pull/17521

## Testing

- Did you test these changes? If so, how?
- Opened the examples before and after and verified the same behavior
was observed. I did this on Ubuntu 24.04.2 LTS using `--features
wayland`.
- Are there any parts that need more testing?
- Other OS's and features can't hurt, but this is such a small change it
shouldn't be a problem.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
  - Run the examples yourself with and without these changes.
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
  - see above

---

## Showcase

n/a

## Migration Guide

n/a
2025-03-21 19:32:12 +00:00