Commit graph

1772 commits

Author SHA1 Message Date
mgi388
bd8faa7ae1
Fix key bindings in 3d_gizmos example after camera controller (#14812)
# Objective

Fixes #14811

## Solution

- Switch `D` to `T`: `T` for "on top of"
- Switch `A` to `B`: `B` in "AABB", or "boxes"

## Testing

- Ran the example locally
- Checked the key bindings that the camera controller uses and made sure
we're not using them in the 3d_gizmos example anymore

After:

<img width="1278" alt="image"
src="https://github.com/user-attachments/assets/4f558d09-5acf-4eb8-8ece-6d4297e62c9f">
2024-08-19 00:20:38 +00:00
Robert Walter
d7cb781977
Switch rotation & translation in grid gizmos (#14656)
# Objective

- Fixes #14655

## Solution

Rotation should happen first as this is more easier to conceptualize in
the mind: We rotate around the coordinate origin `Vec3::ZERO` and then
we just shift the geometry so that its center is exactly on the
specified position

## Testing && Showcase

Code:

```rust
    gizmos.grid(
        Vec3::ONE * 10.0,
        Quat::from_rotation_x(PI / 3. * 2.),
        UVec2::splat(20),
        Vec2::new(2., 2.),
        PURPLE,
    );
    gizmos.sphere(Vec3::ONE * 10.0, Quat::default(), 1.0, PURPLE);
```

Before picture:


![image](https://github.com/user-attachments/assets/7fea2e71-e62b-4763-9f9f-7a1ecd630ada)

After picture:


![image](https://github.com/user-attachments/assets/899dad64-010a-4e4b-86ae-53b85fef0bbc)


## Migration Guide

- Users might have to double check their already existing calls to all
the `grid` methods. It should be more intuitive now though.
2024-08-16 23:40:06 +00:00
Nihilistas
eec38004a8
Add example demonstrating how to enable / disable diagnostics (#14741)
# Objective

fixes #14569

## Solution

added an example to the diagnostic examples and linked the code to the
docs of the diagnostic library itself.

## Testing

I tested locally on my laptop in a web browser. Looked fine. You are
able to collapse the whole "intro" part of the doc to get to the links
sooner (for those who may think that including the example code here is
annoying to scroll through)

I would like people to run ```cargo doc``` and go the bevy_diagnostic
page to see if they have any issues or suggestions.

---

## Showcase

<img width="1067" alt="Screenshot 2024-08-14 at 12 52 16"
src="https://github.com/user-attachments/assets/70b6c18a-0bb9-4656-ba53-c416f62c6116">

---------

Co-authored-by: dpeke <dpekelis@funstage.com>
2024-08-15 20:54:51 +00:00
TotalKrill
6adf31babf
hooking up observers and clicking for ui node (#14695)
Makes the newly merged picking usable for UI elements. 

currently it both triggers the events, as well as sends them as throught
commands.trigger_targets. We should probably figure out if this is
needed for them all.

# Objective

Hooks up obserers and picking for a very simple example

## Solution

upstreamed the UI picking backend from bevy_mod_picking

## Testing

tested with the new example picking/simple_picking.rs


---

---------

Co-authored-by: Lixou <82600264+DasLixou@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
2024-08-15 14:43:55 +00:00
IceSentry
9de25ad330
Add AlphaMask2d phase (#14724)
# Objective

- Bevy now supports an opaque phase for mesh2d, but it's very common for
2d textures to have a transparent alpha channel.

## Solution

- Add an alpha mask phase identical to the one in 3d. It will do the
alpha masking in the shader before drawing the mesh.
- Uses the BinnedRenderPhase
- Since it's an opaque draw it also correctly writes to depth

## Testing

- Tested the mes2d_alpha_mode example and the bevymark example with
alpha mask mode enabled

---

## Showcase


![image](https://github.com/user-attachments/assets/9e5e4561-d0a7-4aa3-b049-d4b1247d5ed4)

The white logo on the right is rendered with alpha mask enabled.

Running the bevymark example I can get 65fps for 120k mesh2d all using
alpha mask.

## Notes

This is one more step for mesh2d improvements
https://github.com/bevyengine/bevy/issues/13265

---------

Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
2024-08-15 14:10:37 +00:00
eckz
46e8c6b662
Consistency between Wireframe2d and Wireframe (#14720)
# Objective

- Wireframe plugins have inconsistencies between 3D and 2D versions.
This PR addresses the following
  - 2d version uses `Srgba` for colors, 3d version uses `Color`.

  
## Solution

- This PR brings consistency by doing the following change
  - `Wireframe2d` now uses `Color` instead of `Srgba`

## Testing

- `wireframe_2d` and `wireframe` examples were verified and they work as
before.

---

## Migration Guide

- `Wireframe2dConfig`.`default_color` type is now `Color` instead of
`Srgba`. Use `.into()` to convert between them.
- `Wireframe2dColor`.`color` type is now `Color` instead of `Srgba`. Use
`.into()` to convert between them.
2024-08-13 18:57:47 +00:00
radiish
6ab8767d3b
reflect: implement the unique reflect rfc (#7207)
# Objective

- Implements the [Unique Reflect
RFC](https://github.com/nicopap/rfcs/blob/bevy-reflect-api/rfcs/56-better-reflect.md).

## Solution

- Implements the RFC.
- This implementation differs in some ways from the RFC:
- In the RFC, it was suggested `Reflect: Any` but `PartialReflect:
?Any`. During initial implementation I tried this, but we assume the
`PartialReflect: 'static` in a lot of places and the changes required
crept out of the scope of this PR.
- `PartialReflect::try_into_reflect` originally returned `Option<Box<dyn
Reflect>>` but i changed this to `Result<Box<dyn Reflect>, Box<dyn
PartialReflect>>` since the method takes by value and otherwise there
would be no way to recover the type. `as_full` and `as_full_mut` both
still return `Option<&(mut) dyn Reflect>`.

---

## Changelog

- Added `PartialReflect`.
- `Reflect` is now a subtrait of `PartialReflect`.
- Moved most methods on `Reflect` to the new `PartialReflect`.
- Added `PartialReflect::{as_partial_reflect, as_partial_reflect_mut,
into_partial_reflect}`.
- Added `PartialReflect::{try_as_reflect, try_as_reflect_mut,
try_into_reflect}`.
- Added `<dyn PartialReflect>::{try_downcast_ref, try_downcast_mut,
try_downcast, try_take}` supplementing the methods on `dyn Reflect`.

## Migration Guide

- Most instances of `dyn Reflect` should be changed to `dyn
PartialReflect` which is less restrictive, however trait bounds should
generally stay as `T: Reflect`.
- The new `PartialReflect::{as_partial_reflect, as_partial_reflect_mut,
into_partial_reflect, try_as_reflect, try_as_reflect_mut,
try_into_reflect}` methods as well as `Reflect::{as_reflect,
as_reflect_mut, into_reflect}` will need to be implemented for manual
implementors of `Reflect`.

## Future Work

- This PR is designed to be followed up by another "Unique Reflect Phase
2" that addresses the following points:
- Investigate making serialization revolve around `Reflect` instead of
`PartialReflect`.
- [Remove the `try_*` methods on `dyn PartialReflect` since they are
stop
gaps](https://github.com/bevyengine/bevy/pull/7207#discussion_r1083476050).
- Investigate usages like `ReflectComponent`. In the places they
currently use `PartialReflect`, should they be changed to use `Reflect`?
- Merging this opens the door to lots of reflection features we haven't
been able to implement.
- We could re-add [the `Reflectable`
trait](8e3488c880/crates/bevy_reflect/src/reflect.rs (L337-L342))
and make `FromReflect` a requirement to improve [`FromReflect`
ergonomics](https://github.com/bevyengine/rfcs/pull/59). This is
currently not possible because dynamic types cannot sensibly be
`FromReflect`.
  - Since this is an alternative to #5772, #5781 would be made cleaner.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-08-12 17:01:41 +00:00
Eero Lehtinen
47c4e3084a
Add custom cursors (#14284)
# Objective

- Add custom images as cursors
- Fixes #9557 

## Solution

- Change cursor type to accommodate both native and image cursors
- I don't really like this solution because I couldn't use
`Handle<Image>` directly. I would need to import `bevy_assets` and that
causes a circular dependency. Alternatively we could use winit's
`CustomCursor` smart pointers, but that seems hard because the event
loop is needed to create those and is not easily accessable for users.
So now I need to copy around rgba buffers which is sad.
- I use a cache because especially on the web creating cursor images is
really slow
- Sorry to #14196 for yoinking, I just wanted to make a quick solution
for myself and thought that I should probably share it too.

Update:
- Now uses `Handle<Image>`, reads rgba data in `bevy_render` and uses
resources to send the data to `bevy_winit`, where the final cursors are
created.

## Testing

- Added example which works fine at least on Linux Wayland (winit side
has been tested with all platforms).
- I haven't tested if the url cursor works.

## Migration Guide

- `CursorIcon` is no longer a field in `Window`, but a separate
component can be inserted to a window entity. It has been changed to an
enum that can hold custom images in addition to system icons.
- `Cursor` is renamed to `CursorOptions` and `cursor` field of `Window`
is renamed to `cursor_options`
- `CursorIcon` is renamed to `SystemCursorIcon`

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
2024-08-12 15:49:03 +00:00
Gino Valente
297c0a3954
bevy_reflect: Add DynamicSet to dynamic_types example (#14665)
# Objective

The `dynamic_types` example was missing a reference to the newly added
`DynamicSet` type.

## Solution

Add `DynamicSet` to the `dynamic_types` example.

For parity with the other dynamic types, I also implemented
`FromIterator<T: Reflect>`, `FromIterator<Box<dyn Reflect>>`, and
`IntoIterator for &DynamicSet`.

## Testing

You can run the example locally:

```
cargo run --example dynamic_types
```
2024-08-08 22:26:18 +00:00
Gino Valente
a0cc636ea3
bevy_reflect: Anonymous function parsing (#14641)
# Objective

### TL;DR

#14098 added the `FunctionRegistry` but had some last minute
complications due to anonymous functions. It ended up going with a
"required name" approach to ensure anonymous functions would always have
a name.

However, this approach isn't ideal for named functions since, by
definition, they will always have a name.

Therefore, this PR aims to modify function reflection such that we can
make function registration easier for named functions, while still
allowing anonymous functions to be registered as well.

### Context

Function registration (#14098) ran into a little problem: anonymous
functions.

Anonymous functions, including function pointers, have very non-unique
type names. For example, the anonymous function `|a: i32, b: i32| a + b`
has the type name of `fn(i32, i32) -> i32`. This obviously means we'd
conflict with another function like `|a: i32, b: i32| a - b`.

The solution that #14098 landed on was to always require a name during
function registration.

The downside with this is that named functions (e.g. `fn add(a: i32, b:
i32) -> i32 { a + b }`) had to redundantly provide a name. Additionally,
manually constructed `DynamicFunction`s also ran into this ergonomics
issue.

I don't entirely know how the function registry will be used, but I have
a strong suspicion that most of its registrations will either be named
functions or manually constructed `DynamicFunction`s, with anonymous
functions only being used here and there for quick prototyping or adding
small functionality.

Why then should the API prioritize the anonymous function use case by
always requiring a name during registration?

#### Telling Functions Apart

Rust doesn't provide a lot of out-of-the-box tools for reflecting
functions. One of the biggest hurdles in attempting to solve the problem
outlined above would be to somehow tell the different kinds of functions
apart.

Let's briefly recap on the categories of functions in Rust:

| Category           | Example                                   |
| ------------------ | ----------------------------------------- |
| Named function     | `fn add(a: i32, b: i32) -> i32 { a + b }` |
| Closure            | `\|a: i32\| a + captured_variable`          |
| Anonymous function | `\|a: i32, b: i32\| a + b`                  |
| Function pointer   | `fn(i32, i32) -> i32`                     |

My first thought was to try and differentiate these categories based on
their size. However, we can see that this doesn't quite work:

| Category           | `size_of` |
| ------------------ | --------- |
| Named function     | 0         |
| Closure            | 0+        |
| Anonymous function | 0         |
| Function pointer   | 8         |

Not only does this not tell anonymous functions from named ones, but it
struggles with pretty much all of them.

My second then was to differentiate based on type name:

| Category           | `type_name`             |
| ------------------ | ----------------------- |
| Named function     | `foo::bar::baz`         |
| Closure            | `foo::bar::{{closure}}` |
| Anonymous function | `fn() -> String`        |
| Function pointer   | `fn() -> String`        |

This is much better. While it can't distinguish between function
pointers and anonymous functions, this doesn't matter too much since we
only care about whether we can _name_ the function.

So why didn't we implement this in #14098?

#### Relying on `type_name`

While this solution was known about while working on #14098, it was left
out from that PR due to it being potentially controversial.

The [docs](https://doc.rust-lang.org/stable/std/any/fn.type_name.html)
for `std::any::type_name` state:

> The returned string must not be considered to be a unique identifier
of a type as multiple types may map to the same type name. Similarly,
there is no guarantee that all parts of a type will appear in the
returned string: for example, lifetime specifiers are currently not
included. In addition, the output may change between versions of the
compiler.

So that's it then? We can't use `type_name`?

Well, this statement isn't so much a rule as it is a guideline. And Bevy
is no stranger to bending the rules to make things work or to improve
ergonomics. Remember that before `TypePath`, Bevy's scene system was
entirely dependent on `type_name`. Not to mention that `type_name` is
being used as a key into both the `TypeRegistry` and the
`FunctionRegistry`.

Bevy's practices aside, can we reliably use `type_name` for this?

My answer would be "yes".

Anonymous functions are anonymous. They have no name. There's nothing
Rust could do to give them a name apart from generating a random string
of characters. But remember that this is a diagnostic tool, it doesn't
make sense to obfuscate the type by randomizing the output. So changing
it to be anything other than what it is now is very unlikely.

The only changes that I could potentially see happening are:

1. Closures replace `{{closure}}` with the name of their variable
2. Lifetimes are included in the output

I don't think the first is likely to happen, but if it does then it
actually works out in our favor: closures are now named!

The second point is probably the likeliest. However, adding lifetimes
doesn't mean we can't still rely on `type_name` to determine whether or
not a function is named. So we should be okay in this case as well.

## Solution

Parse the `type_name` of the function in the `TypedFunction` impl to
determine if the function is named or anonymous.

This once again makes `FunctionInfo::name` optional. For manual
constructions of `DynamicFunction`, `FunctionInfo::named` or
``FunctionInfo::anonymous` can be used.

The `FunctionRegistry` API has also been reworked to account for this
change.

`FunctionRegistry::register` no longer takes a name and instead takes it
from the supplied function, returning a
`FunctionRegistrationError::MissingName` error if the name is `None`.
This also doubles as a replacement for the old
`FunctionRegistry::register_dynamic` method, which has been removed.

To handle anonymous functions, a `FunctionRegistry::register_with_name`
method has been added. This works in the same way
`FunctionRegistry::register` used to work before this PR.

The overwriting methods have been updated in a similar manner, with
modifications to `FunctionRegistry::overwrite_registration`, the removal
of `FunctionRegistry::overwrite_registration_dynamic`, and the addition
of `FunctionRegistry::overwrite_registration_with_name`.

This PR also updates the methods on `App` in a similar way:
`App::register_function` no longer requires a name argument and
`App::register_function_with_name` has been added to handle anonymous
functions (and eventually closures).

## Testing

You can run the tests locally by running:

```
cargo test --package bevy_reflect --features functions
```

---

## Internal Migration Guide

> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.

> [!note]
> This list is not exhaustive. It only contains some of the most
important changes.

`FunctionRegistry::register` no longer requires a name string for named
functions. Anonymous functions, however, need to be registered using
`FunctionRegistry::register_with_name`.

```rust
// BEFORE
registry
  .register(std::any::type_name_of_val(&foo), foo)?
  .register("bar", || println!("Hello world!"));

// AFTER
registry
  .register(foo)?
  .register_with_name("bar", || println!("Hello world!"));
```

`FunctionInfo::name` is now optional. Anonymous functions and closures
will now have their name set to `None` by default. Additionally,
`FunctionInfo::new` has been renamed to `FunctionInfo::named`.
2024-08-07 03:11:08 +00:00
IceSentry
5abc32ceda
Add 2d opaque phase with depth buffer (#13069)
This PR is based on top of #12982

# Objective

- Mesh2d currently only has an alpha blended phase. Most sprites don't
need transparency though.
- For some 2d games it can be useful to have a 2d depth buffer

## Solution

- Add an opaque phase to render Mesh2d that don't need transparency
- This phase currently uses the `SortedRenderPhase` to make it easier to
implement based on the already existing transparent phase. A follow up
PR will switch this to `BinnedRenderPhase`.
- Add a 2d depth buffer
- Use that depth buffer in the transparent phase to make sure that
sprites and transparent mesh2d are displayed correctly

## Testing

I added the mesh2d_transforms example that layers many opaque and
transparent mesh2d to make sure they all get displayed correctly. I also
confirmed it works with sprites by modifying that example locally.

---

## Changelog

- Added `AlphaMode2d`
- Added `Opaque2d` render phase
- Camera2d now have a `ViewDepthTexture` component

## Migration Guide

- `ColorMaterial` now contains `AlphaMode2d`. To keep previous
behaviour, use `AlphaMode::BLEND`. If you know your sprite is opaque,
use `AlphaMode::OPAQUE`

## Follow up PRs

- See tracking issue: #13265

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Christopher Biscardi <chris@christopherbiscardi.com>
2024-08-07 00:22:09 +00:00
Paul Buehne
e7d40c9b08
Fixed typo (#14636)
The closure in the `async_task` example was referred to as a `FnOne`. I
think this should be `FnOnce`.
2024-08-06 17:35:35 +00:00
charlotte
3360b45153
Expose winit's MonitorHandle (#13669)
# Objective

Adds a new `Monitor` component representing a winit `MonitorHandle` that
can be used to spawn new windows and check for system monitor
information.

Closes #12955.

## Solution

For every winit event, check available monitors and spawn them into the
world as components.

## Testing

TODO:
- [x] Test plugging in and unplugging monitor during app runtime
- [x] Test spawning a window on a second monitor by entity id
- [ ] Since this touches winit, test all platforms

---

## Changelog

- Adds a new `Monitor` component that can be queried for information
about available system monitors.

## Migration Guide

- `WindowMode` variants now take a `MonitorSelection`, which can be set
to `MonitorSelection::Primary` to mirror the old behavior.

---------

Co-authored-by: Pascal Hertleif <pascal@technocreatives.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Pascal Hertleif <killercup@gmail.com>
2024-08-06 10:54:37 +00:00
Periwink
3a664b052d
Separate component and resource access (#14561)
# Objective

- Fixes https://github.com/bevyengine/bevy/issues/13139
- Fixes https://github.com/bevyengine/bevy/issues/7255
- Separates component from resource access so that we can correctly
handles edge cases like the issue above
- Inspired from https://github.com/bevyengine/bevy/pull/14472

## Solution

- Update access to have `component` fields and `resource` fields

## Testing

- Added some unit tests
2024-08-06 01:19:39 +00:00
Gino Valente
df61117850
bevy_reflect: Function registry (#14098)
# Objective

#13152 added support for reflecting functions. Now, we need a way to
register those functions such that they may be accessed anywhere within
the ECS.

## Solution

Added a `FunctionRegistry` type similar to `TypeRegistry`.

This allows a function to be registered and retrieved by name.

```rust
fn foo() -> i32 {
    123
}

let mut registry = FunctionRegistry::default();
registry.register("my_function", foo);

let function = registry.get_mut("my_function").unwrap();
let value = function.call(ArgList::new()).unwrap().unwrap_owned();
assert_eq!(value.downcast_ref::<i32>(), Some(&123));
```

Additionally, I added an `AppFunctionRegistry` resource which wraps a
`FunctionRegistryArc`. Functions can be registered into this resource
using `App::register_function` or by getting a mutable reference to the
resource itself.

### Limitations

#### `Send + Sync`

In order to get this registry to work across threads, it needs to be
`Send + Sync`. This means that `DynamicFunction` needs to be `Send +
Sync`, which means that its internal function also needs to be `Send +
Sync`.

In most cases, this won't be an issue because standard Rust functions
(the type most likely to be registered) are always `Send + Sync`.
Additionally, closures tend to be `Send + Sync` as well, granted they
don't capture any `!Send` or `!Sync` variables.

This PR adds this `Send + Sync` requirement, but as mentioned above, it
hopefully shouldn't be too big of an issue.

#### Closures

Unfortunately, closures can't be registered yet. This will likely be
explored and added in a followup PR.

### Future Work

Besides addressing the limitations listed above, another thing we could
look into is improving the lookup of registered functions. One aspect is
in the performance of hashing strings. The other is in the developer
experience of having to call `std::any::type_name_of_val` to get the
name of their function (assuming they didn't give it a custom name).

## Testing

You can run the tests locally with:

```
cargo test --package bevy_reflect
```

---

## Changelog

- Added `FunctionRegistry`
- Added `AppFunctionRegistry` (a `Resource` available from `bevy_ecs`)
- Added `FunctionRegistryArc`
- Added `FunctionRegistrationError`
- Added `reflect_functions` feature to `bevy_ecs` and `bevy_app`
- `FunctionInfo` is no longer `Default`
- `DynamicFunction` now requires its wrapped function be `Send + Sync`

## Internal Migration Guide

> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.

`DynamicFunction` (both those created manually and those created with
`IntoFunction`), now require `Send + Sync`. All standard Rust functions
should meet that requirement. Closures, on the other hand, may not if
they capture any `!Send` or `!Sync` variables from its environment.
2024-08-06 01:09:48 +00:00
akimakinai
c1c003d3c7
Fix num_cascades in split_screen exmample for WebGL (#14601)
# Objective

- Fixes #14595

## Solution

- Use `num_cascades: 1` in WebGL build.
`CascadeShadowConfigBuilder::default()` gives this number in WebGL:
8235daaea0/crates/bevy_pbr/src/light/mod.rs (L241-L248)

## Testing

- Tested the modified example in WebGL with Firefox/Chrome

---------

Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2024-08-04 13:57:22 +00:00
Rob Parrett
5b29402cc8
Add with_child to simplify spawning when there will only be one child (#14594)
# Objective

This idea came up in the context of a hypothetical "text sections as
entities" where text sections are children of a text bundle.

```rust
commands
    .spawn(TextBundle::default())
    .with_children(|parent} {
        parent.spawn(TextSection::from("Hello"));
    });
```

This is a bit cumbersome (but powerful and probably the way things are
headed). [`bsn!`](https://github.com/bevyengine/bevy/discussions/14437)
will eventually make this nicer, but in the mean time, this might
improve ergonomics for the common case where there is only one
`TextSection`.

## Solution

Add a `with_child` method to the `BuildChildren` trait that spawns a
single bundle and adds it as a child to the entity.

```rust
commands
    .spawn(TextBundle::default())
    .with_child(TextSection::from("Hello"));
```

## Testing

I added some tests, and modified the `button` example to use the new
method.

If any potential co-authors want to improve the tests, that would be
great.

## Alternatives

- Some sort of macro. See
https://github.com/tigregalis/bevy_spans_ent/blob/main/examples/macro.rs#L20.
I don't love this, personally, and it would probably be obsoleted by
`bsn!`.
- Wait for `bsn!`
- Add `with_children_batch` that takes an `Into<Iterator>` of bundles.
  ```rust
  with_children_batch(vec![TextSection::from("Hello")])
  ```
This is maybe not as useful as it sounds -- it only works with
homogeneous bundles, so no marker components or styles.
- If this doesn't seem valuable, doing nothing is cool with me.
2024-08-02 15:37:15 +00:00
Jan Hohenheim
6f7c554daa
Fix common capitalization errors in documentation (#14562)
WASM -> Wasm
MacOS -> macOS

Nothing important, just something that annoyed me for a while :)
2024-07-31 21:16:05 +00:00
IceSentry
bfcb19a871
Add example showing how to use SpecializedMeshPipeline (#14370)
# Objective

- A lot of mid-level rendering apis are hard to figure out because they
don't have any examples
- SpecializedMeshPipeline can be really useful in some cases when you
want more flexibility than a Material without having to go to low level
apis.

## Solution

- Add an example showing how to make a custom `SpecializedMeshPipeline`.

## Testing

- Did you test these changes? If so, how?
- Are there any parts that need more testing?
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?

---

## Showcase

The examples just spawns 3 triangles in a triangle pattern.


![image](https://github.com/user-attachments/assets/c3098758-94c4-4775-95e5-1d7c7fb9eb86)

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-07-31 18:24:58 +00:00
Rich Churcher
924f1cbc02
Fix lints in nightly (#14543)
# Objective

Similar to #14537 , this fixes a minor lint issue causing CI failures
when using nightly toolchain.

## Solution

Add `#[allow(dead_code)]` to unused sample code.

## Testing

`cargo run -p ci -- lints` using 1.82 toolchain.
2024-07-31 01:35:19 +00:00
s-puig
ba09f35474
Fix UI texture atlas with offset (#13620)
# Objective

- Fixes #11219 

## Solution

- Scaling calculations use texture dimensions instead of layout
dimensions.

## Testing

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

All UI examples look fine.

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

Example in #11219

## Migration Guide

```diff
let ui_node = ExtractedUiNode {
                    stack_index,
                    transform,
                    color,
                    rect,
                    image,
-                   atlas_size: Some(atlas_size * scale_factor),      
+                   atlas_scaling: Some(Vec2::splat(scale_factor)),
                    clip,
                    flip_x,
                    flip_y,
                    camera_entity,
                    border,
                    border_radius,
                    node_type,
                },
```

```diff
let computed_slices = ComputedTextureSlices {
    slices,
-    image_size,
}
```
2024-07-30 15:31:58 +00:00
Aevyrie
9575b20d31
Track source location in change detection (#14034)
# Objective

- Make it possible to know *what* changed your component or resource.
- Common need when debugging, when you want to know the last code
location that mutated a value in the ECS.
- This feature would be very useful for the editor alongside system
stepping.

## Solution

- Adds the caller location to column data.
- Mutations now `track_caller` all the way up to the public API.
- Commands that invoke these functions immediately call
`Location::caller`, and pass this into the functions, instead of the
functions themselves attempting to get the caller. This would not work
for commands which are deferred, as the commands are executed by the
scheduler, not the user's code.

## Testing

- The `component_change_detection` example now shows where the component
was mutated:

```
2024-07-28T06:57:48.946022Z  INFO component_change_detection: Entity { index: 1, generation: 1 }: New value: MyComponent(0.0)
2024-07-28T06:57:49.004371Z  INFO component_change_detection: Entity { index: 1, generation: 1 }: New value: MyComponent(1.0)
2024-07-28T06:57:49.012738Z  WARN component_change_detection: Change detected!
        -> value: Ref(MyComponent(1.0))
        -> added: false
        -> changed: true
        -> changed by: examples/ecs/component_change_detection.rs:36:23
```

- It's also possible to inspect change location from a debugger:
<img width="608" alt="image"
src="https://github.com/user-attachments/assets/c90ecc7a-0462-457a-80ae-42e7f5d346b4">


---

## Changelog

- Added source locations to ECS change detection behind the
`track_change_detection` flag.

## Migration Guide

- Added `changed_by` field to many internal ECS functions used with
change detection when the `track_change_detection` feature flag is
enabled. Use Location::caller() to provide the source of the function
call.

---------

Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-07-30 12:02:38 +00:00
Sarthak Singh
a9f4fd8ea1
Disabled usage of the POLYGON_MODE_LINE gpu feature in the examples (#14402)
Fixes #14353
Fixes #14371

---------

Signed-off-by: Sarthak Singh <sarthak.singh99@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
2024-07-29 23:40:39 +00:00
Rich Churcher
848e7fae43
Use AccumulatedMouseMotion, AccumulatedMouseScroll in examples (#14488)
# Objective

Use the new `AccumulatedMouseMotion` and `AccumulatedMouseScroll`
resources in place of mouse event handling.

I left the `mouse_input_events` example alone, since by its nature it
demonstrates event detection.

Fixes #14066 

## Testing

Ran each example locally before and after changes.
2024-07-29 23:38:59 +00:00
Matty
601cf6b9e5
Refactor Bounded2d/Bounded3d to use isometries (#14485)
# Objective

Previously, this area of bevy_math used raw translation and rotations to
encode isometries, which did not exist earlier. The goal of this PR is
to make the codebase of bevy_math more harmonious by using actual
isometries (`Isometry2d`/`Isometry3d`) in these places instead — this
will hopefully make the interfaces more digestible for end-users, in
addition to facilitating conversions.

For instance, together with the addition of #14478, this means that a
bounding box for a collider with an isometric `Transform` can be
computed as
```rust
collider.aabb_3d(collider_transform.to_isometry())
```
instead of using manual destructuring. 

## Solution

- The traits `Bounded2d` and `Bounded3d` now use `Isometry2d` and
`Isometry3d` (respectively) instead of `translation` and `rotation`
parameters; e.g.:
  ```rust
  /// A trait with methods that return 3D bounding volumes for a shape.
  pub trait Bounded3d {
/// Get an axis-aligned bounding box for the shape translated and
rotated by the given isometry.
      fn aabb_3d(&self, isometry: Isometry3d) -> Aabb3d;
/// Get a bounding sphere for the shape translated and rotated by the
given isometry.
      fn bounding_sphere(&self, isometry: Isometry3d) -> BoundingSphere;
  }
  ```
- Similarly, the `from_point_cloud` constructors for axis-aligned
bounding boxes and bounding circles/spheres now take isometries instead
of separate `translation` and `rotation`; e.g.:
  ```rust
/// Computes the smallest [`Aabb3d`] containing the given set of points,
/// transformed by the rotation and translation of the given isometry.
    ///
    /// # Panics
    ///
    /// Panics if the given set of points is empty.
    #[inline(always)]
    pub fn from_point_cloud(
        isometry: Isometry3d,
        points: impl Iterator<Item = impl Into<Vec3A>>,
    ) -> Aabb3d { //... }
  ```

This has a couple additional results:
1. The end-user no longer interacts directly with `Into<Vec3A>` or
`Into<Rot2>` parameters; these conversions all happen earlier now,
inside the isometry types.
2. Similarly, almost all intermediate `Vec3 -> Vec3A` conversions have
been eliminated from the `Bounded3d` implementations for primitives.
This probably has some performance benefit, but I have not measured it
as of now.

## Testing

Existing unit tests help ensure that nothing has been broken in the
refactor.

---

## Migration Guide

The `Bounded2d` and `Bounded3d` traits now take `Isometry2d` and
`Isometry3d` parameters (respectively) instead of separate translation
and rotation arguments. Existing calls to `aabb_2d`, `bounding_circle`,
`aabb_3d`, and `bounding_sphere` will have to be changed to use
isometries instead. A straightforward conversion is to refactor just by
calling `Isometry2d/3d::new`, as follows:
```rust
// Old:
let aabb = my_shape.aabb_2d(my_translation, my_rotation);

// New:
let aabb = my_shape.aabb_2d(Isometry2d::new(my_translation, my_rotation));
```

However, if the old translation and rotation are 3d
translation/rotations originating from a `Transform` or
`GlobalTransform`, then `to_isometry` may be used instead. For example:
```rust
// Old:
let bounding_sphere = my_shape.bounding_sphere(shape_transform.translation, shape_transform.rotation);

// New:
let bounding_sphere = my_shape.bounding_sphere(shape_transform.to_isometry());
```

This discussion also applies to the `from_point_cloud` construction
method of `Aabb2d`/`BoundingCircle`/`Aabb3d`/`BoundingSphere`, which has
similarly been altered to use isometries.
2024-07-29 23:37:02 +00:00
Matty
74cecb27bb
Disallow empty cubic and rational curves (#14382)
# Objective

Previously, our cubic spline constructors would produce
`CubicCurve`/`RationalCurve` output with no data when they themselves
didn't hold enough control points to produce a well-formed curve.
Attempting to sample the resulting empty "curves" (e.g. by calling
`CubicCurve::position`) would crash the program (😓).

The objectives of this PR are: 
1. Ensure that the curve output of `bevy_math`'s spline constructions
are never invalid as data.
2. Provide a type-level guarantee that `CubicCurve` and `RationalCurve`
actually function as curves.

## Solution

This has a few pieces. Firstly, the curve generator traits
`CubicGenerator`, `CyclicCubicGenerator`, and `RationalGenerator` are
now fallible — they have associated error types, and the
curve-generation functions are allowed to fail:
```rust
/// Implement this on cubic splines that can generate a cubic curve from their spline parameters.
pub trait CubicGenerator<P: VectorSpace> {
    /// An error type indicating why construction might fail.
    type Error;

    /// Build a [`CubicCurve`] by computing the interpolation coefficients for each curve segment.
    fn to_curve(&self) -> Result<CubicCurve<P>, Self::Error>;
}
```

All existing spline constructions use this together with errors that
indicate when they didn't have the right control data and provide curves
which have at least one segment whenever they return an `Ok` variant.

Next, `CubicCurve` and `RationalCurve` have been blessed with a
guarantee that their internal array of segments (`segments`) is never
empty. In particular, this field is no longer public, so that invalid
curves cannot be built using struct instantiation syntax. To compensate
for this shortfall for users (in particular library authors who might
want to implement their own generators), there is a new method
`from_segments` on these for constructing a curve from a list of
segments, failing if the list is empty:
```rust
/// Create a new curve from a collection of segments. If the collection of segments is empty,
/// a curve cannot be built and `None` will be returned instead.
pub fn from_segments(segments: impl Into<Vec<CubicSegment<P>>>) -> Option<Self> { //... }
```

All existing methods on `CyclicCurve` and `CubicCurve` maintain the
invariant, so the direct construction of invalid values by users is
impossible.

## Testing

Run unit tests from `bevy_math::cubic_splines`. Additionally, run the
`cubic_splines` example and try to get it to crash using small numbers
of control points: it uses the fallible constructors directly, so if
invalid data is ever constructed, it is basically guaranteed to crash.

---

## Migration Guide

The `to_curve` method on Bevy's cubic splines is now fallible (returning
a `Result`), meaning that any existing calls will need to be updated by
handling the possibility of an error variant.

Similarly, any custom implementation of `CubicGenerator` or
`RationalGenerator` will need to be amended to include an `Error` type
and be made fallible itself.

Finally, the fields of `CubicCurve` and `RationalCurve` are now private,
so any direct constructions of these structs from segments will need to
be replaced with the new `CubicCurve::from_segments` and
`RationalCurve::from_segments` methods.

---

## Design

The main thing to justify here is the choice for the curve internals to
remain the same. After all, if they were able to cause crashes in the
first place, it's worth wondering why safeguards weren't put in place on
the types themselves to prevent that.

My view on this is that the problem was really that the internals of
these methods implicitly relied on the assumption that the value they
were operating on was *actually a curve*, when this wasn't actually
guaranteed. Now, it's possible to make a bunch of small changes inside
the curve struct methods to account for that, but I think that's worse
than just guaranteeing that the data is valid upstream — sampling is
about as hot a code path as we're going to get in this area, and hitting
an additional branch every time it happens just to check that the struct
contains valid data is probably a waste of resources.

Another way of phrasing this is that even if we're only interested in
solving the crashes, the curve's validity needs to be checked at some
point, and it's almost certainly better to do this once at the point of
construction than every time the curve is sampled.

In cases where the control data is supplied dynamically, users would
already have to deal with empty curve outputs basically not working.
Anecdotally, I ran into this while writing the `cubic_splines` example,
and I think the diff illustrates the improvement pretty nicely — the
code no longer has to anticipate whether the output will be good or not;
it just has to handle the `Result`.

The cost of all this, of course, is that we have to guarantee that the
new invariant is actually maintained whenever we extend the API.
However, for the most part, I don't expect users to want to do much
surgery on the internals of their curves anyway.
2024-07-29 23:25:14 +00:00
Giacomo Stevanato
71c5f1e3e4
Generate links to definition in source code pages on docs.rs and dev-docs.bevyengine.org (#12965)
# Objective

- Fix issue #2611

## Solution

- Add `--generate-link-to-definition` to all the `rustdoc-args` arrays
in the `Cargo.toml`s (for docs.rs)
- Add `--generate-link-to-definition` to the `RUSTDOCFLAGS` environment
variable in the docs workflow (for dev-docs.bevyengine.org)
- Document all the workspace crates in the docs workflow (needed because
otherwise only the source code of the `bevy` package will be included,
making the argument useless)
- I think this also fixes #3662, since it fixes the bug on
dev-docs.bevyengine.org, while on docs.rs it has been fixed for a while
on their side.

---

## Changelog

- The source code viewer on docs.rs now includes links to the
definitions.
2024-07-29 23:10:16 +00:00
re0312
65628ed4aa
fix meshlet example (#14471)
# Objective

- meshlet example has broken since #14273

## Solution

- disable msaa in meshlet example

Co-authored-by: François Mockers <mockersf@gmail.com>
2024-07-25 15:22:11 +00:00
Robert Walter
52a2a3b146
Dedicated Reflect implementation for Set-like things (#13014)
# Objective

I just wanted to inspect `HashSet`s in `bevy-inspector-egui` but I
noticed that it didn't work for some reason. A few minutes later I found
myself looking into the bevy reflect impls noticing that `HashSet`s have
been covered only rudimentary up until now.

## Solution

I'm not sure if this is overkill (especially the first bullet), but
here's a list of the changes:

- created a whole new trait and enum variants for `ReflectRef` and the
like called `Set`
- mostly oriented myself at the `Map` trait and made the necessary
changes until RA was happy
- create macro `impl_reflect_for_hashset!` and call it on `std::HashSet`
and `hashbrown::HashSet`

Extra notes:

- no `get_mut` or `get_mut_at` mirroring the `std::HashSet`
- `insert[_boxed]` and `remove` return `bool` mirroring `std::HashSet`,
additionally that bool is reflect as I thought that would be how we
handle things in bevy reflect, but I'm not sure on this
- ser/de are handled via `SeqAccess`
- I'm not sure about the general deduplication property of this impl of
`Set` that is generally expected? I'm also not sure yet if `Map` does
provide this. This mainly refers to the `Dynamic[...]` structs
- I'm not sure if there are other methods missing from the `trait`, I
felt like `contains` or the set-operations (union/diff/...) could've
been helpful, but I wanted to get out the bare minimum for feedback
first

---

## Changelog

### Added
- `Set` trait for `bevy_reflect`

### Changed
- `std::collections::HashSet` and `bevy_utils::hashbrown::HashSet` now
implement a more complete set of reflect functionalities instead of
"just" `reflect_value`
- `TypeInfo` contains a new variant `Set` that contains `SetInfo`
- `ReflectKind` contains a new variant `Set`
- `ReflectRef` contains a new variant `Set`
- `ReflectMut` contains a new variant `Set`
- `ReflectOwned` contains a new variant `Set`

## Migration Guide

- The new `Set` variants on the enums listed in the change section
should probably be considered by people working with this level of the
lib
### Help wanted! 

I'm not sure if this change is able to break code. From my understanding
it shouldn't since we just add functionality but I'm not sure yet if
theres anything missing from my impl that would be normally provided by
`impl_reflect_value!`
2024-07-24 19:43:26 +00:00
François Mockers
8dc6ccfbe7
fix examples after the switch for msaa to a component (#14446)
# Objective

- #14273 changed MSAA to a component, and broke some examples

- SSAO needs MSAA to be disabled

f0ff7fb544/crates/bevy_pbr/src/ssao/mod.rs (L495)

- `AlphaMode::AlphaToCoverage` needs MSAA to be not off to do something

f0ff7fb544/examples/3d/transparency_3d.rs (L113-L117)

# Solution

- change MSAA in those examples
2024-07-24 01:22:00 +00:00
IceSentry
3faca1e549
Don't ignore draw errors (#13240)
# Objective

- It's possible to have errors in a draw command, but these errors are
ignored

## Solution

- Return a result with the error

## Changelog

Renamed `RenderCommandResult::Failure` to `RenderCommandResult::Skip`
Added a `reason` string parameter to `RenderCommandResult::Failure`

## Migration Guide
If you were using `RenderCommandResult::Failure` to just ignore an error
and retry later, use `RenderCommandResult::Skip` instead.

This wasn't intentional, but this PR should also help with
https://github.com/bevyengine/bevy/issues/12660 since we can turn a few
unwraps into error messages now.

---------

Co-authored-by: Charlotte McElwain <charlotte.c.mcelwain@gmail.com>
2024-07-22 19:22:30 +00:00
Coder-Joe458
8f5345573c
Remove manual --cfg docsrs (#14376)
# Objective

- Fixes #14132 

## Solution

- Remove the cfg docsrs
2024-07-22 18:58:04 +00:00
charlotte
03fd1b46ef
Move Msaa to component (#14273)
Switches `Msaa` from being a globally configured resource to a per
camera view component.

Closes #7194

# Objective

Allow individual views to describe their own MSAA settings. For example,
when rendering to different windows or to different parts of the same
view.

## Solution

Make `Msaa` a component that is required on all camera bundles.

## Testing

Ran a variety of examples to ensure that nothing broke.

TODO:
- [ ] Make sure android still works per previous comment in
`extract_windows`.

---

## Migration Guide

`Msaa` is no longer configured as a global resource, and should be
specified on each spawned camera if a non-default setting is desired.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François Mockers <francois.mockers@vleue.com>
2024-07-22 18:28:23 +00:00
Rob Parrett
7fb927f725
Fix button placement in split_screen example (#14405)
# Objective

Fixes the buttons in `split_screen` touching the edge of the viewport.

## Solution

This seems like it might potentially be "normal css-like" behavior with
absolutely positioned nodes and padding.
<details>
<summary>HTML test</summary>

```html
<html>
<body>
    <div style="width: 100%; height: 100%; padding: 20px;">
        <div style="width: 100%; height: 100%; padding: 20px; display: flex; justify-content: space-between; align-items: center">
            <div style="width: 40px; height: 40px; border: 1px solid black;">&lt;</div>
            <div style="width: 40px; height: 40px; border: 1px solid black;">&gt;</div>
        </div>
    </div>
</body>
</html>
```

</details>

Instead I just removed the padding from the root node.

## Testing

Added ui debug gizmos to the example and checked before/after.

Before:
<img width="1280" alt="Screenshot 2024-07-20 at 9 23 09 AM"
src="https://github.com/user-attachments/assets/f3cac637-8de9-4acf-bb13-994791998bb7">

After:
<img width="1280" alt="Screenshot 2024-07-20 at 9 37 27 AM"
src="https://github.com/user-attachments/assets/4d3c23b4-5a48-45da-b8a5-a394fd34a44b">
2024-07-20 17:17:14 +00:00
Liam Gallagher
11ecc4d322
docs: Fix incorrect docs in the run conditions example (#14377)
## Objective

Make the docs say the right thing.

## Solution

Edit the docs so they say the right thing.

Seems like overtime the example has changed but the comment did not
change with it. It originally was a AND but is now an OR.
2024-07-20 16:51:05 +00:00
charlotte
3aa525885b
Set scissor on upscale to match camera viewport (#14287)
# Objective

When the user renders multiple cameras to the same output texture, it
can sometimes be confusing what `ClearColorConfig` is necessary for each
camera to avoid overwriting the previous camera's output. This is
particular true in cases where the user uses mixed HDR cameras, which
means that their scene is being rendered to different internal textures.

## Solution

When a view has a configured viewport, set the GPU scissor in the
upscaling node so we don't overwrite areas that were written to by other
cameras.

## Testing

Ran the `split_screen` example.
2024-07-20 16:45:04 +00:00
Rob Parrett
490792ba7a
Fix tracing with transform_hierarchy example (#14374)
# Objective

Fixes #7433
Alternative to #14323

## Solution

Add `DefaultPlugins` so we actually have tracing spans when using
`trace_tracy` or `trace_chrome`.

## Testing

```
cargo run --release --features trace_tracy --example transform_hierarchy large_tree
```
This now connects to Tracy and sends a bunch of data.
2024-07-20 16:38:24 +00:00
Sou1gh0st
9da18cce2a
Add support for environment map transformation (#14290)
# Objective

- Fixes: https://github.com/bevyengine/bevy/issues/14036

## Solution

- Add a world space transformation for the environment sample direction.

## Testing

- I have tested the newly added `transform` field using the newly added
`rotate_environment_map` example.


https://github.com/user-attachments/assets/2de77c65-14bc-48ee-b76a-fb4e9782dbdb


## Migration Guide

- Since we have added a new filed to the `EnvironmentMapLight` struct,
users will need to include `..default()` or some rotation value in their
initialization code.
2024-07-19 15:00:50 +00:00
Matty
3484bd916f
Cyclic splines (#14106)
# Objective

Fill a gap in the functionality of our curve constructions by allowing
users to easily build cyclic curves from control data.

## Solution

Here I opted for something lightweight and discoverable. There is a new
`CyclicCubicGenerator` trait with a method `to_curve_cyclic` which uses
splines' control data to create curves that are cyclic. For now, its
signature is exactly like that of `CubicGenerator` — `to_curve_cyclic`
just yields a `CubicCurve`:
```rust
/// Implement this on cubic splines that can generate a cyclic cubic curve from their spline parameters.
///
/// This makes sense only when the control data can be interpreted cyclically.
pub trait CyclicCubicGenerator<P: VectorSpace> {
    /// Build a cyclic [`CubicCurve`] by computing the interpolation coefficients for each curve segment.
    fn to_curve_cyclic(&self) -> CubicCurve<P>;
}
```

This trait has been implemented for `CubicHermite`,
`CubicCardinalSpline`, `CubicBSpline`, and `LinearSpline`:

<img width="753" alt="Screenshot 2024-07-01 at 8 58 27 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/69ae0802-3b78-4fb9-b73a-6f842cf3b33c">
<img width="628" alt="Screenshot 2024-07-01 at 9 00 14 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/2992175a-a96c-40fc-b1a1-5206c3572cde">
<img width="606" alt="Screenshot 2024-07-01 at 8 59 36 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/9e99eb3a-dbe6-42da-886c-3d3e00410d03">
<img width="603" alt="Screenshot 2024-07-01 at 8 59 01 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/d037bc0c-396a-43af-ab5c-fad9a29417ef">

(Each type pictured respectively with the control points rendered as
green spheres; tangents not pictured in the case of the Hermite spline.)

These curves are all parametrized so that the output of `to_curve` and
the output of `to_curve_cyclic` are similar. For instance, in
`CubicCardinalSpline`, the first output segment is a curve segment
joining the first and second control points in each, although it is
constructed differently. In the other cases, the segments from
`to_curve` are a subset of those in `to_curve_cyclic`, with the new
segments appearing at the end.

## Testing

I rendered cyclic splines from control data and made sure they looked
reasonable. Existing tests are intact for splines where previous code
was modified. (Note that the coefficient computation for cyclic spline
segments is almost verbatim identical to that of their non-cyclic
counterparts.)

The Bezier benchmarks also look fine.

---

## Changelog

- Added `CyclicCubicGenerator` trait to `bevy_math::cubic_splines` for
creating cyclic curves from control data.
- Implemented `CyclicCubicGenerator` for `CubicHermite`,
`CubicCardinalSpline`, `CubicBSpline`, and `LinearSpline`.
- `bevy_math` now depends on `itertools`.

---

## Discussion

### Design decisions

The biggest thing here is just the approach taken in the first place:
namely, the cyclic constructions use new methods on the same old
structs. This choice was made to reduce friction and increase
discoverability but also because creating new ones just seemed
unnecessary: the underlying data would have been the same, so creating
something like "`CyclicCubicBSpline`" whose internally-held control data
is regarded as cyclic in nature doesn't really accomplish much — the end
result for the user is basically the same either way.

Similarly, I don't presently see a pressing need for `to_curve_cyclic`
to output something other than a `CubicCurve`, although changing this in
the future may be useful. See below.

A notable omission here is that `CyclicCubicGenerator` is not
implemented for `CubicBezier`. This is not a gap waiting to be filled —
`CubicBezier` just doesn't have enough data to join its start with its
end without just making up the requisite control points wholesale. In
all the cases where `CyclicCubicGenerator` has been implemented here,
the fashion in which the ends are connected is quite natural and follows
the semantics of the associated spline construction.

### Future direction

There are two main things here:
1. We should investigate whether we should do something similar for
NURBS. I just don't know that much about NURBS at the moment, so I
regarded this as out of scope for the PR.
2. We may eventually want to change the output type of
`CyclicCubicGenerator::to_curve_cyclic` to a type which reifies the
cyclic nature of the curve output. This wasn't done in this PR because
I'm unsure how much value a type-level guarantee of cyclicity actually
has, but if some useful features make sense only in the case of cyclic
curves, this might be worth pursuing.
2024-07-17 13:02:31 +00:00
Patrick Walton
bc34216929
Pack multiple vertex and index arrays together into growable buffers. (#14257)
This commit uses the [`offset-allocator`] crate to combine vertex and
index arrays from different meshes into single buffers. Since the
primary source of `wgpu` overhead is from validation and synchronization
when switching buffers, this significantly improves Bevy's rendering
performance on many scenes.

This patch is a more flexible version of #13218, which also used slabs.
Unlike #13218, which used slabs of a fixed size, this commit implements
slabs that start small and can grow. In addition to reducing memory
usage, supporting slab growth reduces the number of vertex and index
buffer switches that need to happen during rendering, leading to
improved performance. To prevent pathological fragmentation behavior,
slabs are capped to a maximum size, and mesh arrays that are too large
get their own dedicated slabs.

As an additional improvement over #13218, this commit allows the
application to customize all allocator heuristics. The
`MeshAllocatorSettings` resource contains values that adjust the minimum
and maximum slab sizes, the cutoff point at which meshes get their own
dedicated slabs, and the rate at which slabs grow. Hopefully-sensible
defaults have been chosen for each value.

Unfortunately, WebGL 2 doesn't support the *base vertex* feature, which
is necessary to pack vertex arrays from different meshes into the same
buffer. `wgpu` represents this restriction as the downlevel flag
`BASE_VERTEX`. This patch detects that bit and ensures that all vertex
buffers get dedicated slabs on that platform. Even on WebGL 2, though,
we can combine all *index* arrays into single buffers to reduce buffer
changes, and we do so.

The following measurements are on Bistro:

Overall frame time improves from 8.74 ms to 5.53 ms (1.58x speedup):
![Screenshot 2024-07-09
163521](https://github.com/bevyengine/bevy/assets/157897/5d83c824-c0ee-434c-bbaf-218ff7212c48)

Render system time improves from 6.57 ms to 3.54 ms (1.86x speedup):
![Screenshot 2024-07-09
163559](https://github.com/bevyengine/bevy/assets/157897/d94e2273-c3a0-496a-9f88-20d394129610)

Opaque pass time improves from 4.64 ms to 2.33 ms (1.99x speedup):
![Screenshot 2024-07-09
163536](https://github.com/bevyengine/bevy/assets/157897/e4ef6e48-d60e-44ae-9a71-b9a731c99d9a)

## Migration Guide

### Changed

* Vertex and index buffers for meshes may now be packed alongside other
buffers, for performance.
* `GpuMesh` has been renamed to `RenderMesh`, to reflect the fact that
it no longer directly stores handles to GPU objects.
* Because meshes no longer have their own vertex and index buffers, the
responsibility for the buffers has moved from `GpuMesh` (now called
`RenderMesh`) to the `MeshAllocator` resource. To access the vertex data
for a mesh, use `MeshAllocator::mesh_vertex_slice`. To access the index
data for a mesh, use `MeshAllocator::mesh_index_slice`.

[`offset-allocator`]: https://github.com/pcwalton/offset-allocator
2024-07-16 20:33:15 +00:00
Gino Valente
af865e76a3
bevy_reflect: Improve DynamicFunction ergonomics (#14201)
# Objective

Many functions can be converted to `DynamicFunction` using
`IntoFunction`. Unfortunately, we are limited by Rust itself and the
implementations are far from exhaustive. For example, we can't convert
functions with more than 16 arguments. Additionally, we can't handle
returns with lifetimes not tied to the lifetime of the first argument.

In such cases, users will have to create their `DynamicFunction`
manually.

Let's take the following function:

```rust
fn get(index: usize, list: &Vec<String>) -> &String {
    &list[index]
}
```

This function cannot be converted to a `DynamicFunction` via
`IntoFunction` due to the lifetime of the return value being tied to the
second argument. Therefore, we need to construct the `DynamicFunction`
manually:

```rust
DynamicFunction::new(
    |mut args, info| {
        let list = args
            .pop()
            .unwrap()
            .take_ref::<Vec<String>>(&info.args()[1])?;
        let index = args.pop().unwrap().take_owned::<usize>(&info.args()[0])?;
        Ok(Return::Ref(get(index, list)))
    },
    FunctionInfo::new()
        .with_name("get")
        .with_args(vec![
            ArgInfo:🆕:<usize>(0).with_name("index"),
            ArgInfo:🆕:<&Vec<String>>(1).with_name("list"),
        ])
        .with_return_info(ReturnInfo:🆕:<&String>()),
);
```

While still a small and straightforward snippet, there's a decent amount
going on here. There's a lot of room for improvements when it comes to
ergonomics and readability.

The goal of this PR is to address those issues.

## Solution

Improve the ergonomics and readability of manually created
`DynamicFunction`s.

Some of the major changes:
1. Removed the need for `&ArgInfo` when reifying arguments (i.e. the
`&info.args()[1]` calls)
2. Added additional `pop` methods on `ArgList` to handle both popping
and casting
3. Added `take` methods on `ArgList` for taking the arguments out in
order
4. Removed the need for `&FunctionInfo` in the internal closure (Change
1 made it no longer necessary)
5. Added methods to automatically handle generating `ArgInfo` and
`ReturnInfo`

With all these changes in place, we get something a lot nicer to both
write and look at:

```rust
DynamicFunction::new(
    |mut args| {
        let index = args.take::<usize>()?;
        let list = args.take::<&Vec<String>>()?;
        Ok(Return::Ref(get(index, list)))
    },
    FunctionInfo::new()
        .with_name("get")
        .with_arg::<usize>("index")
        .with_arg::<&Vec<String>>("list")
        .with_return::<&String>(),
);
```

Alternatively, to rely on type inference for taking arguments, you could
do:

```rust
DynamicFunction::new(
    |mut args| {
        let index = args.take_owned()?;
        let list = args.take_ref()?;
        Ok(Return::Ref(get(index, list)))
    },
    FunctionInfo::new()
        .with_name("get")
        .with_arg::<usize>("index")
        .with_arg::<&Vec<String>>("list")
        .with_return::<&String>(),
);
```

## Testing

You can test locally by running:

```
cargo test --package bevy_reflect
```

---

## Changelog

- Removed `&ArgInfo` argument from `FromArg::from_arg` trait method
- Removed `&ArgInfo` argument from `Arg::take_***` methods
- Added `ArgValue`
- `Arg` is now a struct containing an `ArgValue` and an argument `index`
- `Arg::take_***` methods now require `T` is also `TypePath`
- Added `Arg::new`, `Arg::index`, `Arg::value`, `Arg::take_value`, and
`Arg::take` methods
- Replaced `ArgId` in `ArgError` with just the argument `index`
- Added `ArgError::EmptyArgList`
- Renamed `ArgList::push` to `ArgList::push_arg`
- Added `ArgList::pop_arg`, `ArgList::pop_owned`, `ArgList::pop_ref`,
and `ArgList::pop_mut`
- Added `ArgList::take_arg`, `ArgList::take_owned`, `ArgList::take_ref`,
`ArgList::take_mut`, and `ArgList::take`
- `ArgList::pop` is now generic
- Renamed `FunctionError::InvalidArgCount` to
`FunctionError::ArgCountMismatch`
- The closure given to `DynamicFunction::new` no longer has a
`&FunctionInfo` argument
- Added `FunctionInfo::with_arg`
- Added `FunctionInfo::with_return`

## Internal Migration Guide

> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.

* The `FromArg::from_arg` trait method and the `Arg::take_***` methods
no longer take a `&ArgInfo` argument.
* What used to be `Arg` is now `ArgValue`. `Arg` is now a struct which
contains an `ArgValue`.
* `Arg::take_***` methods now require `T` is also `TypePath`
* Instances of `id: ArgId` in `ArgError` have been replaced with `index:
usize`
* `ArgList::push` is now `ArgList::push_arg`. It also takes the new
`ArgValue` type.
* `ArgList::pop` has become `ArgList::pop_arg` and now returns
`ArgValue`. `Arg::pop` now takes a generic type and downcasts to that
type. It's recommended to use `ArgList::take` and friends instead since
they allow removing the arguments from the list in the order they were
pushed (rather than reverse order).
* `FunctionError::InvalidArgCount` is now
`FunctionError::ArgCountMismatch`
* The closure given to `DynamicFunction::new` no longer has a
`&FunctionInfo` argument. This argument can be removed.
2024-07-16 13:01:52 +00:00
Mike
cfcb56f5b9
Remove need for EventLoopProxy to be NonSend (#14198)
# Objective

- Continue to pare down the uses on NonSend resources in the engine. In
this case, EventLoopProxy used to be `!Sync`, but is now `Sync` in the
latest version of winit.

## Solution

- New type `EventLoopProxy` as `EventLoopProxyWrapper` to make it into a
normal resource.
- Update the `custom_user_event` example as it no longer needs to
indirectly access the `EventLoopProxy` through a static variable
anymore.

## Testing

- Ran the example. The resource exists just for users to use, so there
aren't any in engine uses for it currently.

---

## Changelog

- make EventLoopProxy into a regular resource. 

## Migration Guide

`EventLoopProxy` has been renamed to `EventLoopProxyWrapper` and is now
`Send`, making it an ordinary resource.

Before:
```rust
event_loop_system(event_loop: NonSend<EventLoopProxy<MyEvent>>) {
    event_loop.send_event(MyEvent);
}
```

After:
```rust
event_loop_system(event_loop: Res<EventLoopProxy<MyEvent>>) {
    event_loop.send_event(MyEvent);
}
```
2024-07-16 06:59:01 +00:00
Gino Valente
1042f09c2e
bevy_reflect: Add DynamicClosure and DynamicClosureMut (#14141)
# Objective

As mentioned in
[this](https://github.com/bevyengine/bevy/pull/13152#issuecomment-2198387297)
comment, creating a function registry (see #14098) is a bit difficult
due to the requirements of `DynamicFunction`. Internally, a
`DynamicFunction` contains a `Box<dyn FnMut>` (the function that reifies
reflected arguments and calls the actual function), which requires `&mut
self` in order to be called.

This means that users would require a mutable reference to the function
registry for it to be useful— which isn't great. And they can't clone
the `DynamicFunction` either because cloning an `FnMut` isn't really
feasible (wrapping it in an `Arc` would allow it to be cloned but we
wouldn't be able to call the clone since we need a mutable reference to
the `FnMut`, which we can't get with multiple `Arc`s still alive,
requiring us to also slap in a `Mutex`, which adds additional overhead).

And we don't want to just replace the `dyn FnMut` with `dyn Fn` as that
would prevent reflecting closures that mutate their environment.

Instead, we need to introduce a new type to split the requirements of
`DynamicFunction`.

## Solution

Introduce new types for representing closures.

Specifically, this PR introduces `DynamicClosure` and
`DynamicClosureMut`. Similar to how `IntoFunction` exists for
`DynamicFunction`, two new traits were introduced: `IntoClosure` and
`IntoClosureMut`.

Now `DynamicFunction` stores a `dyn Fn` with a `'static` lifetime.
`DynamicClosure` also uses a `dyn Fn` but has a lifetime, `'env`, tied
to its environment. `DynamicClosureMut` is most like the old
`DynamicFunction`, keeping the `dyn FnMut` and also typing its lifetime,
`'env`, to the environment

Here are some comparison tables:

|   | `DynamicFunction` | `DynamicClosure` | `DynamicClosureMut` |
| - | ----------------- | ---------------- | ------------------- |
| Callable with `&self` |  |  |  |
| Callable with `&mut self` |  |  |  |
| Allows for non-`'static` lifetimes |  |  |  |

|   | `IntoFunction` | `IntoClosure` | `IntoClosureMut` |
| - | -------------- | ------------- | ---------------- |
| Convert `fn` functions |  |  |  |
| Convert `fn` methods |  |  |  |
| Convert anonymous functions |  |  |  |
| Convert closures that capture immutable references |  |  |  |
| Convert closures that capture mutable references |  |  |  |
| Convert closures that capture owned values | [^1] |  |  |

[^1]: Due to limitations in Rust, `IntoFunction` can't be implemented
for just functions (unless we forced users to manually coerce them to
function pointers first). So closures that meet the trait requirements
_can technically_ be converted into a `DynamicFunction` as well. To both
future-proof and reduce confusion, though, we'll just pretend like this
isn't a thing.

```rust
let mut list: Vec<i32> = vec![1, 2, 3];

// `replace` is a closure that captures a mutable reference to `list`
let mut replace = |index: usize, value: i32| -> i32 {
  let old_value = list[index];
  list[index] = value;
  old_value
};

// Convert the closure into a dynamic closure using `IntoClosureMut::into_closure_mut`
let mut func: DynamicClosureMut = replace.into_closure_mut();

// Dynamically call the closure:
let args = ArgList::default().push_owned(1_usize).push_owned(-2_i32);
let value = func.call_once(args).unwrap().unwrap_owned();

// Check the result:
assert_eq!(value.take::<i32>().unwrap(), 2);
assert_eq!(list, vec![1, -2, 3]);
```

### `ReflectFn`/`ReflectFnMut`

To make extending the function reflection system easier (the blanket
impls for `IntoFunction`, `IntoClosure`, and `IntoClosureMut` are all
incredibly short), this PR generalizes callables with two new traits:
`ReflectFn` and `ReflectFnMut`.

These traits mimic `Fn` and `FnMut` but allow for being called via
reflection. In fact, their blanket implementations are identical save
for `ReflectFn` being implemented over `Fn` types and `ReflectFnMut`
being implemented over `FnMut` types.

And just as `Fn` is a subtrait of `FnMut`, `ReflectFn` is a subtrait of
`ReflectFnMut`. So anywhere that expects a `ReflectFnMut` can also be
given a `ReflectFn`.

To reiterate, these traits aren't 100% necessary. They were added in
purely for extensibility. If we decide to split things up differently or
add new traits/types in the future, then those changes should be much
simpler to implement.

### `TypedFunction`

Because of the split into `ReflectFn` and `ReflectFnMut`, we needed a
new way to access the function type information. This PR moves that
concept over into `TypedFunction`.

Much like `Typed`, this provides a way to access a function's
`FunctionInfo`.

By splitting this trait out, it helps to ensure the other traits are
focused on a single responsibility.

### Internal Macros

The original function PR (#13152) implemented `IntoFunction` using a
macro which was passed into an `all_tuples!` macro invocation. Because
we needed the same functionality for these new traits, this PR has
copy+pasted that code for `ReflectFn`, `ReflectFnMut`, and
`TypedFunction`— albeit with some differences between them.

Originally, I was going to try and macro-ify the impls and where clauses
such that we wouldn't have to straight up duplicate a lot of this logic.
However, aside from being more complex in general, autocomplete just
does not play nice with such heavily nested macros (tried in both
RustRover and VSCode). And both of those problems told me that it just
wasn't worth it: we need to ensure the crate is easily maintainable,
even at the cost of duplicating code.

So instead, I made sure to simplify the macro code by removing all
fully-qualified syntax and cutting the where clauses down to the bare
essentials, which helps to clean up a lot of the visual noise. I also
tried my best to document the macro logic in certain areas (I may even
add a bit more) to help with maintainability for future devs.

### Documentation

Documentation for this module was a bit difficult for me. So many of
these traits and types are very interconnected. And each trait/type has
subtle differences that make documenting it in a single place, like at
the module level, difficult to do cleanly. Describing the valid
signatures is also challenging to do well.

Hopefully what I have here is okay. I think I did an okay job, but let
me know if there any thoughts on ways to improve it. We can also move
such a task to a followup PR for more focused discussion.

## Testing

You can test locally by running:

```
cargo test --package bevy_reflect
```

---

## Changelog

- Added `DynamicClosure` struct
- Added `DynamicClosureMut` struct
- Added `IntoClosure` trait
- Added `IntoClosureMut` trait
- Added `ReflectFn` trait
- Added `ReflectFnMut` trait
- Added `TypedFunction` trait
- `IntoFunction` now only works for standard Rust functions
- `IntoFunction` no longer takes a lifetime parameter
- `DynamicFunction::call` now only requires `&self`
- Removed `DynamicFunction::call_once`
- Changed the `IntoReturn::into_return` signature to include a where
clause

## Internal Migration Guide

> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.

### `IntoClosure`

`IntoFunction` now only works for standard Rust functions. Calling
`IntoFunction::into_function` on a closure that captures references to
its environment (either mutable or immutable), will no longer compile.

Instead, you will need to use either `IntoClosure::into_closure` to
create a `DynamicClosure` or `IntoClosureMut::into_closure_mut` to
create a `DynamicClosureMut`, depending on your needs:

```rust
let punct = String::from("!");
let print = |value: String| {
    println!("{value}{punct}");
};

// BEFORE
let func: DynamicFunction = print.into_function();

// AFTER
let func: DynamicClosure = print.into_closure();
```

### `IntoFunction` lifetime

Additionally, `IntoFunction` no longer takes a lifetime parameter as it
always expects a `'static` lifetime. Usages will need to remove any
lifetime parameters:

```rust
// BEFORE
fn execute<'env, F: IntoFunction<'env, Marker>, Marker>(f: F) {/* ... */}

// AFTER
fn execute<F: IntoFunction<Marker>, Marker>(f: F) {/* ... */}
```

### `IntoReturn`

`IntoReturn::into_return` now has a where clause. Any manual
implementors will need to add this where clause to their implementation.
2024-07-16 03:22:43 +00:00
Patrick Walton
20c6bcdba4
Allow volumetric fog to be localized to specific, optionally voxelized, regions. (#14099)
Currently, volumetric fog is global and affects the entire scene
uniformly. This is inadequate for many use cases, such as local smoke
effects. To address this problem, this commit introduces *fog volumes*,
which are axis-aligned bounding boxes (AABBs) that specify fog
parameters inside their boundaries. Such volumes can also specify a
*density texture*, a 3D texture of voxels that specifies the density of
the fog at each point.

To create a fog volume, add a `FogVolume` component to an entity (which
is included in the new `FogVolumeBundle` convenience bundle). Like light
probes, a fog volume is conceptually a 1×1×1 cube centered on the
origin; a transform can be used to position and resize this region. Many
of the fields on the existing `VolumetricFogSettings` have migrated to
the new `FogVolume` component. `VolumetricFogSettings` on a camera is
still needed to enable volumetric fog. However, by itself
`VolumetricFogSettings` is no longer sufficient to enable volumetric
fog; a `FogVolume` must be present. Applications that wish to retain the
old global fog behavior can simply surround the scene with a large fog
volume.

By way of implementation, this commit converts the volumetric fog shader
from a full-screen shader to one applied to a mesh. The strategy is
different depending on whether the camera is inside or outside the fog
volume. If the camera is inside the fog volume, the mesh is simply a
plane scaled to the viewport, effectively falling back to a full-screen
pass. If the camera is outside the fog volume, the mesh is a cube
transformed to coincide with the boundaries of the fog volume's AABB.
Importantly, in the latter case, only the front faces of the cuboid are
rendered. Instead of treating the boundaries of the fog as a sphere
centered on the camera position, as we did prior to this patch, we
raytrace the far planes of the AABB to determine the portion of each ray
contained within the fog volume. We then raymarch in shadow map space as
usual. If a density texture is present, we modulate the fixed density
value with the trilinearly-interpolated value from that texture.

Furthermore, this patch introduces optional jitter to fog volumes,
intended for use with TAA. This modifies the position of the ray from
frame to frame using interleaved gradient noise, in order to reduce
aliasing artifacts. Many implementations of volumetric fog in games use
this technique. Note that this patch makes no attempt to write a motion
vector; this is because when a view ray intersects multiple voxels
there's no single direction of motion. Consequently, fog volumes can
have ghosting artifacts, but because fog is "ghostly" by its nature,
these artifacts are less objectionable than they would be for opaque
objects.

A new example, `fog_volumes`, has been added. It demonstrates a single
fog volume containing a voxelized representation of the Stanford bunny.
The existing `volumetric_fog` example has been updated to use the new
local volumetrics API.

## Changelog

### Added

* Local `FogVolume`s are now supported, to localize fog to specific
regions. They can optionally have 3D density voxel textures for precise
control over the distribution of the fog.

### Changed

* `VolumetricFogSettings` on a camera no longer enables volumetric fog;
instead, it simply enables the processing of `FogVolume`s within the
scene.

## Migration Guide

* A `FogVolume` is now necessary in order to enable volumetric fog, in
addition to `VolumetricFogSettings` on the camera. Existing uses of
volumetric fog can be migrated by placing a large `FogVolume`
surrounding the scene.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2024-07-16 03:14:12 +00:00
Chris Biscardi
73d7e89a18
remove rounded_borders and merge with borders example (#14317)
# Objective

The borders example is separate from the rounded borders example. If you
find the borders example, you may miss the rounded borders example.

## Solution

Merge the examples in a basic way, since there is enough room to show
all options at the same time.

I also considered renaming the borders and rounded borders examples so
that they would be located next to each other in repo and UI, but it
felt like having a singular example was better.

## Testing

```
cargo run --example borders
```

---

## Showcase

The merged example looks like this:

![screenshot-2024-07-14-at-13 40
10@2x](https://github.com/user-attachments/assets/0f49cc46-1ca0-40d0-abec-020cbf0fb205)
2024-07-15 16:54:05 +00:00
Ben Frankel
7cb97852a5
Remove second generic from .add_before, .add_after (#14285)
# Objective

```rust
// Currently:
builder.add_after::<FooPlugin, _>(BarPlugin);
// After this PR:
builder.add_after::<FooPlugin>(BarPlugin);
```

This removes some weirdness and better parallels the rest of the
`PluginGroupBuilder` API.

## Solution

Define a helper method `type_id_of_val` to use in `.add_before` and
`.add_after` instead of `TypeId::of::<T>` (which requires the plugin
type to be nameable, preventing `impl Plugin` from being used).

## Testing

Ran `cargo run -p ci lints` successfully.

## Migration Guide

Removed second generic from `PluginGroupBuilder` methods: `add_before`
and `add_after`.

```rust
// Before:
DefaultPlugins
    .build()
    .add_before::<WindowPlugin, _>(FooPlugin)
    .add_after::<WindowPlugin, _>(BarPlugin)

// After:
DefaultPlugins
    .build()
    .add_before::<WindowPlugin>(FooPlugin)
    .add_after::<WindowPlugin>(BarPlugin)
```

---------

Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
2024-07-15 15:58:14 +00:00
Sou1gh0st
65aae92127
Add support for skybox transformation (#14267)
# Objective

- Fixes https://github.com/bevyengine/bevy/issues/14036

## Solution

- Add a view space transformation for the skybox

## Testing

- I have tested the newly added `transform` field using the `skybox`
example.
```
diff --git a/examples/3d/skybox.rs b/examples/3d/skybox.rs
index beaf5b268..d16cbe988 100644
--- a/examples/3d/skybox.rs
+++ b/examples/3d/skybox.rs
@@ -81,6 +81,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
         Skybox {
             image: skybox_handle.clone(),
             brightness: 1000.0,
+            rotation: Quat::from_rotation_x(PI * -0.5),
         },
     ));
```
<img width="1280" alt="image"
src="https://github.com/bevyengine/bevy/assets/6300263/1230a608-58ea-492d-a811-90c54c3b43ef">


## Migration Guide
- Since we have added a new filed to the Skybox struct, users will need
to include `..Default::default()` or some rotation value in their
initialization code.
2024-07-15 15:53:20 +00:00
SpecificProtagonist
ab255aefc6
Implement FromIterator/IntoIterator for dynamic types (#14250)
# Objective

Implement FromIterator/IntoIterator for dynamic types where missing

Note:
- can't impl `IntoIterator` for `&Array` & co because of orphan rules
- `into_iter().collect()` is a no-op for `Vec`s because of
specialization

---

## Migration Guide

- Change `DynamicArray::from_vec` to `DynamicArray::from_iter`
2024-07-15 15:38:11 +00:00
Pixelstorm
0f7c548a4a
Component Lifecycle Hook & Observer Trigger for replaced values (#14212)
# Objective

Fixes #14202

## Solution

Add `on_replaced` component hook and `OnReplaced` observer trigger

## Testing

- Did you test these changes? If so, how?
  - Updated & added unit tests

---

## Changelog

- Added new `on_replaced` component hook and `OnReplaced` observer
trigger for performing cleanup on component values when they are
overwritten with `.insert()`
2024-07-15 15:24:15 +00:00
JMS55
6e8d43a037
Faster MeshletMesh deserialization (#14193)
# Objective
- Using bincode to deserialize binary into a MeshletMesh is expensive
(~77ms for a 5mb file).

## Solution
- Write a custom deserializer using bytemuck's Pod types and slice
casting.
  - Total asset load time has gone from ~102ms to ~12ms.
- Change some types I never meant to be public to private and other misc
cleanup.

## Testing
- Ran the meshlet example and added timing spans to the asset loader.

---

## Changelog
- Improved `MeshletMesh` loading speed
- The `MeshletMesh` disk format has changed, and
`MESHLET_MESH_ASSET_VERSION` has been bumped
- `MeshletMesh` fields are now private
- Renamed `MeshletMeshSaverLoad` to `MeshletMeshSaverLoader`
- The `Meshlet`, `MeshletBoundingSpheres`, and `MeshletBoundingSphere`
types are now private
- Removed `MeshletMeshSaveOrLoadError::SerializationOrDeserialization`
- Added `MeshletMeshSaveOrLoadError::WrongFileType`

## Migration Guide
- Regenerate your `MeshletMesh` assets, as the disk format has changed,
and `MESHLET_MESH_ASSET_VERSION` has been bumped
- `MeshletMesh` fields are now private
- `MeshletMeshSaverLoad` is now named `MeshletMeshSaverLoader`
- The `Meshlet`, `MeshletBoundingSpheres`, and `MeshletBoundingSphere`
types are now private
- `MeshletMeshSaveOrLoadError::SerializationOrDeserialization` has been
removed
- Added `MeshletMeshSaveOrLoadError::WrongFileType`, match on this
variant if you match on `MeshletMeshSaveOrLoadError`
2024-07-15 15:06:02 +00:00
Antony
5f3a529920
Fix inconsistency in KeyboardInput examples to match migration guide (#14185)
# Objective

- The API usage of `KeyboardInput` in the `char_input_events` and
`text_input` examples don't match the [migration
guide](https://bevyengine.org/learn/migration-guides/0-13-to-0-14/#deprecate-receivedcharacter).

## Solution

- Check using `is_pressed` over `ButtonState::Released`.
2024-07-15 15:03:48 +00:00
Gino Valente
276815a9a0
examples: Add Type Data reflection example (#13903)
# Objective

Type data is a **super** useful tool to know about when working with
reflection. However, most users don't fully understand how it works or
that you can use it for more than just object-safe traits.

This is unfortunate because it can be surprisingly simple to manually
create your own type data.

We should have an example detailing how type works, how users can define
their own, and how thy can be used.

## Solution

Added a `type_data` example.

This example goes through all the major points about type data:
- Why we need them
- How they can be defined
- The two ways they can be registered
- A list of common/important type data provided by Bevy

I also thought it might be good to go over the `#[reflect_trait]` macro
as part of this example since it has all the other context, including
how to define type data in places where `#[reflect_trait]` won't work.
Because of this, I removed the `trait_reflection` example.

## Testing

You can run the example locally with the following command:

```
cargo run --example type_data
```

---

## Changelog

- Added the `type_data` example
- Removed the `trait_reflection` example
2024-07-15 14:19:50 +00:00
Patrick Walton
fcda67e894
Start a built-in postprocessing stack, and implement chromatic aberration in it. (#13695)
This commit creates a new built-in postprocessing shader that's designed
to hold miscellaneous postprocessing effects, and starts it off with
chromatic aberration. Possible future effects include vignette, film
grain, and lens distortion.

[Chromatic aberration] is a common postprocessing effect that simulates
lenses that fail to focus all colors of light to a single point. It's
often used for impact effects and/or horror games. This patch uses the
technique from *Inside* ([Gjøl & Svendsen 2016]), which allows the
developer to customize the particular color pattern to achieve different
effects. Unity HDRP uses the same technique, while Unreal has a
hard-wired fixed color pattern.

A new example, `post_processing`, has been added, in order to
demonstrate the technique. The existing `post_processing` shader has
been renamed to `custom_post_processing`, for clarity.

[Chromatic aberration]:
https://en.wikipedia.org/wiki/Chromatic_aberration

[Gjøl & Svendsen 2016]:
https://github.com/playdeadgames/publications/blob/master/INSIDE/rendering_inside_gdc2016.pdf

![Screenshot 2024-06-04
180304](https://github.com/bevyengine/bevy/assets/157897/3631c64f-a615-44fe-91ca-7f04df0a54b2)

![Screenshot 2024-06-04
180743](https://github.com/bevyengine/bevy/assets/157897/ee055cbf-4314-49c5-8bfa-8d8a17bd52bb)

## Changelog

### Added

* Chromatic aberration is now available as a built-in postprocessing
effect. To use it, add `ChromaticAberration` to your camera.
2024-07-15 13:59:02 +00:00
Miles Silberling-Cook
ed2b8e0f35
Minimal Bubbling Observers (#13991)
# Objective

Add basic bubbling to observers, modeled off `bevy_eventlistener`.

## Solution

- Introduce a new `Traversal` trait for components which point to other
entities.
- Provide a default `TraverseNone: Traversal` component which cannot be
constructed.
- Implement `Traversal` for `Parent`.
- The `Event` trait now has an associated `Traversal` which defaults to
`TraverseNone`.
- Added a field `bubbling: &mut bool` to `Trigger` which can be used to
instruct the runner to bubble the event to the entity specified by the
event's traversal type.
- Added an associated constant `SHOULD_BUBBLE` to `Event` which
configures the default bubbling state.
- Added logic to wire this all up correctly.

Introducing the new associated information directly on `Event` (instead
of a new `BubblingEvent` trait) lets us dispatch both bubbling and
non-bubbling events through the same api.

## Testing

I have added several unit tests to cover the common bugs I identified
during development. Running the unit tests should be enough to validate
correctness. The changes effect unsafe portions of the code, but should
not change any of the safety assertions.

## Changelog

Observers can now bubble up the entity hierarchy! To create a bubbling
event, change your `Derive(Event)` to something like the following:

```rust
#[derive(Component)]
struct MyEvent;

impl Event for MyEvent {
    type Traverse = Parent; // This event will propagate up from child to parent.
    const AUTO_PROPAGATE: bool = true; // This event will propagate by default.
}
```

You can dispatch a bubbling event using the normal
`world.trigger_targets(MyEvent, entity)`.

Halting an event mid-bubble can be done using
`trigger.propagate(false)`. Events with `AUTO_PROPAGATE = false` will
not propagate by default, but you can enable it using
`trigger.propagate(true)`.

If there are multiple observers attached to a target, they will all be
triggered by bubbling. They all share a bubbling state, which can be
accessed mutably using `trigger.propagation_mut()` (`trigger.propagate`
is just sugar for this).

You can choose to implement `Traversal` for your own types, if you want
to bubble along a different structure than provided by `bevy_hierarchy`.
Implementers must be careful never to produce loops, because this will
cause bevy to hang.

## Migration Guide
+ Manual implementations of `Event` should add associated type `Traverse
= TraverseNone` and associated constant `AUTO_PROPAGATE = false`;
+ `Trigger::new` has new field `propagation: &mut Propagation` which
provides the bubbling state.
+ `ObserverRunner` now takes the same `&mut Propagation` as a final
parameter.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2024-07-15 13:39:41 +00:00
Johannes Vollmer
57d05927d6
update gltf example to use type-safe GltfAssetLabel::Scene (#14218)
# Objective

update the `load_gltf_extras.rs` example to the newest bevy api

## Solution

uses the new type-safe code for loading the scene #0 from the gltf
instead of a path suffix

## Testing

the example runs as expected
2024-07-14 15:42:32 +00:00
François Mockers
d008227553
update example low_power (#14224)
# Objective

- Show both `RequestRedraw` and `WakeUp`
- Partly adresses #14214

---------

Co-authored-by: Aevyrie <aevyrie@gmail.com>
2024-07-14 15:42:07 +00:00
Sunil Thunga
5ffdc0c93f
Moves smooth_follow to movement dir (#14249)
# Objective

- Moves the smooth_follow.rs into movement directory in examples
- Fixes #14241

## Solution

- Move the smooth_follow.rs to movement dir in examples.
2024-07-09 18:22:47 +00:00
Jan Hohenheim
d0e606b87c
Add an example for doing movement in fixed timesteps (#14223)
_copy-pasted from my doc comment in the code_

# Objective

This example shows how to properly handle player input, advance a
physics simulation in a fixed timestep, and display the results.

The classic source for how and why this is done is Glenn Fiedler's
article [Fix Your
Timestep!](https://gafferongames.com/post/fix_your_timestep/).

## Motivation

The naive way of moving a player is to just update their position like
so:
```rust
transform.translation += velocity;
```
The issue here is that the player's movement speed will be tied to the
frame rate.
Faster machines will move the player faster, and slower machines will
move the player slower.
In fact, you can observe this today when running some old games that did
it this way on modern hardware!
The player will move at a breakneck pace.

The more sophisticated way is to update the player's position based on
the time that has passed:
```rust
transform.translation += velocity * time.delta_seconds();
```
This way, velocity represents a speed in units per second, and the
player will move at the same speed regardless of the frame rate.

However, this can still be problematic if the frame rate is very low or
very high. If the frame rate is very low, the player will move in large
jumps. This may lead to a player moving in such large jumps that they
pass through walls or other obstacles. In general, you cannot expect a
physics simulation to behave nicely with *any* delta time. Ideally, we
want to have some stability in what kinds of delta times we feed into
our physics simulation.

The solution is using a fixed timestep. This means that we advance the
physics simulation by a fixed amount at a time. If the real time that
passed between two frames is less than the fixed timestep, we simply
don't advance the physics simulation at all.
If it is more, we advance the physics simulation multiple times until we
catch up. You can read more about how Bevy implements this in the
documentation for
[`bevy::time::Fixed`](https://docs.rs/bevy/latest/bevy/time/struct.Fixed.html).

This leaves us with a last problem, however. If our physics simulation
may advance zero or multiple times per frame, there may be frames in
which the player's position did not need to be updated at all, and some
where it is updated by a large amount that resulted from running the
physics simulation multiple times. This is physically correct, but
visually jarring. Imagine a player moving in a straight line, but
depending on the frame rate, they may sometimes advance by a large
amount and sometimes not at all. Visually, we want the player to move
smoothly. This is why we need to separate the player's position in the
physics simulation from the player's position in the visual
representation. The visual representation can then be interpolated
smoothly based on the last and current actual player position in the
physics simulation.

This is a tradeoff: every visual frame is now slightly lagging behind
the actual physical frame, but in return, the player's movement will
appear smooth. There are other ways to compute the visual representation
of the player, such as extrapolation. See the [documentation of the
lightyear
crate](https://cbournhonesque.github.io/lightyear/book/concepts/advanced_replication/visual_interpolation.html)
for a nice overview of the different methods and their tradeoffs.

## Implementation

- The player's velocity is stored in a `Velocity` component. This is the
speed in units per second.
- The player's current position in the physics simulation is stored in a
`PhysicalTranslation` component.
- The player's previous position in the physics simulation is stored in
a `PreviousPhysicalTranslation` component.
- The player's visual representation is stored in Bevy's regular
`Transform` component.
- Every frame, we go through the following steps:
- Advance the physics simulation by one fixed timestep in the
`advance_physics` system.
This is run in the `FixedUpdate` schedule, which runs before the
`Update` schedule.
- Update the player's visual representation in the
`update_displayed_transform` system.
This interpolates between the player's previous and current position in
the physics simulation.
- Update the player's velocity based on the player's input in the
`handle_input` system.

## Relevant Issues

Related to #1259.
I'm also fairly sure I've seen an issue somewhere made by
@alice-i-cecile about showing how to move a character correctly in a
fixed timestep, but I cannot find it.
2024-07-09 14:23:10 +00:00
Bob Gardner
ec1aa48fc6
Created an EventMutator for when you want to mutate an event before reading (#13818)
# Objective

- Often in games you will want to create chains of systems that modify
some event. For example, a chain of damage systems that handle a
DamageEvent and modify the underlying value before the health system
finally consumes the event. Right now this requires either:

* Using a component added to the entity
* Consuming and refiring events

Neither is ideal when really all we want to do is read the events value,
modify it, and write it back.

## Solution

- Create an EventMutator class similar to EventReader but with ResMut<T>
and iterators that return &mut so that events can be mutated.

## Testing

- I replicated all the existing tests for EventReader to make sure
behavior was the same (I believe) and added a number of tests specific
to testing that 1) events can actually be mutated, and that 2)
EventReader sees changes from EventMutator for events it hasn't already
seen.

## Migration Guide

Users currently using `ManualEventReader` should use `EventCursor`
instead. `ManualEventReader` will be removed in Bevy 0.16. Additionally,
`Events::get_reader` has been replaced by `Events::get_cursor`.

Users currently directly accessing the `Events` resource for mutation
should move to `EventMutator` if possible.

---------

Co-authored-by: poopy <gonesbird@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-07-08 14:53:06 +00:00
Jenya705
330911f1bf
Component Hook functions as attributes for Component derive macro (#14005)
# Objective

Fixes https://github.com/bevyengine/bevy/issues/13972

## Solution

Added 3 new attributes to the `Component` macro.

## Testing

Added `component_hook_order_spawn_despawn_with_macro_hooks`, that makes
the same as `component_hook_order_spawn_despawn` but uses a struct, that
defines it's hooks with the `Component` macro.

---

---------

Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-07-08 00:46:00 +00:00
Ben Frankel
3452781bf7
Deduplicate Wasm optimization instructions (#14173)
See https://github.com/bevyengine/bevy-website/pull/1538 for context.
2024-07-06 15:38:29 +00:00
TotalKrill
5986d5d309
Cosmic text (#10193)
# Replace ab_glyph with the more capable cosmic-text

Fixes #7616.

Cosmic-text is a more mature text-rendering library that handles scripts
and ligatures better than ab_glyph, it can also handle system fonts
which can be implemented in bevy in the future

Rebase of https://github.com/bevyengine/bevy/pull/8808

## Changelog

Replaces text renderer ab_glyph with cosmic-text

The definition of the font size has changed with the migration to cosmic
text. The behavior is now consistent with other platforms (e.g. the
web), where the font size in pixels measures the height of the font (the
distance between the top of the highest ascender and the bottom of the
lowest descender). Font sizes in your app need to be rescaled to
approximately 1.2x smaller; for example, if you were using a font size
of 60.0, you should now use a font size of 50.0.

## Migration guide

- `Text2dBounds` has been replaced with `TextBounds`, and it now accepts
`Option`s to the bounds, instead of using `f32::INFINITY` to inidicate
lack of bounds
- Textsizes should be changed, dividing the current size with 1.2 will
result in the same size as before.
- `TextSettings` struct is removed
- Feature `subpixel_alignment` has been removed since cosmic-text
already does this automatically
- TextBundles and things rendering texts requires the `CosmicBuffer`
Component on them as well

## Suggested followups:

- TextPipeline: reconstruct byte indices for keeping track of eventual
cursors in text input
- TextPipeline: (future work) split text entities into section entities
- TextPipeline: (future work) text editing
- Support line height as an option. Unitless `1.2` is the default used
in browsers (1.2x font size).
- Support System Fonts and font families
- Example showing of animated text styles. Eg. throbbing hyperlinks

---------

Co-authored-by: tigregalis <anak.harimau@gmail.com>
Co-authored-by: Nico Burns <nico@nicoburns.com>
Co-authored-by: sam edelsten <samedelsten1@gmail.com>
Co-authored-by: Dimchikkk <velo.app1@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
2024-07-04 20:41:08 +00:00
Rob Parrett
c8d8ea6d4f
Fix border color in ui_texture_slice and ui_texture_atlas_slice examples. (#14121)
# Objective

Fixes #14120

`ui_texture_slice` and `ui_texture_atlas_slice` were working as
intended, so undo the changes.

## Solution

Partially revert https://github.com/bevyengine/bevy/pull/14115 for
`ui_texture_slice` and `ui_texture_atlas_slice`.

## Testing

Ran those two examples, confirmed the border color is the thing that
changes when buttons are hovered.
2024-07-03 13:51:44 +00:00
François Mockers
160bcc787c
fix remaining issues with background color in examples (#14115)
# Objective

- Fixes #14097

## Solution

- Switching the uses of `UiImage` in examples to `BackgroundColor` when
needed
2024-07-03 01:13:55 +00:00
Joseph
5876352206
Optimize common usages of AssetReader (#14082)
# Objective

The `AssetReader` trait allows customizing the behavior of fetching
bytes for an `AssetPath`, and expects implementors to return `dyn
AsyncRead + AsyncSeek`. This gives implementors of `AssetLoader` great
flexibility to tightly integrate their asset loading behavior with the
asynchronous task system.

However, almost all implementors of `AssetLoader` don't use the async
functionality at all, and just call `AsyncReadExt::read_to_end(&mut
Vec<u8>)`. This is incredibly inefficient, as this method repeatedly
calls `poll_read` on the trait object, filling the vector 32 bytes at a
time. At my work we have assets that are hundreds of megabytes which
makes this a meaningful overhead.

## Solution

Turn the `Reader` type alias into an actual trait, with a provided
method `read_to_end`. This provided method should be more efficient than
the existing extension method, as the compiler will know the underlying
type of `Reader` when generating this function, which removes the
repeated dynamic dispatches and allows the compiler to make further
optimizations after inlining. Individual implementors are able to
override the provided implementation -- for simple asset readers that
just copy bytes from one buffer to another, this allows removing a large
amount of overhead from the provided implementation.

Now that `Reader` is an actual trait, I also improved the ergonomics for
implementing `AssetReader`. Currently, implementors are expected to box
their reader and return it as a trait object, which adds unnecessary
boilerplate to implementations. This PR changes that trait method to
return a pseudo trait alias, which allows implementors to return `impl
Reader` instead of `Box<dyn Reader>`. Now, the boilerplate for boxing
occurs in `ErasedAssetReader`.

## Testing

I made identical changes to my company's fork of bevy. Our app, which
makes heavy use of `read_to_end` for asset loading, still worked
properly after this. I am not aware if we have a more systematic way of
testing asset loading for correctness.

---

## Migration Guide

The trait method `bevy_asset::io::AssetReader::read` (and `read_meta`)
now return an opaque type instead of a boxed trait object. Implementors
of these methods should change the type signatures appropriately

```rust
impl AssetReader for MyReader {
    // Before
    async fn read<'a>(&'a self, path: &'a Path) -> Result<Box<Reader<'a>>, AssetReaderError> {
        let reader = // construct a reader
        Box::new(reader) as Box<Reader<'a>>
    }

    // After
    async fn read<'a>(&'a self, path: &'a Path) -> Result<impl Reader + 'a, AssetReaderError> {
        // create a reader
    }
}
```

`bevy::asset::io::Reader` is now a trait, rather than a type alias for a
trait object. Implementors of `AssetLoader::load` will need to adjust
the method signature accordingly

```rust
impl AssetLoader for MyLoader {
    async fn load<'a>(
        &'a self,
        // Before:
        reader: &'a mut bevy::asset::io::Reader,
        // After:
        reader: &'a mut dyn bevy::asset::io::Reader,
        _: &'a Self::Settings,
        load_context: &'a mut LoadContext<'_>,
    ) -> Result<Self::Asset, Self::Error> {
}
```

Additionally, implementors of `AssetReader` that return a type
implementing `futures_io::AsyncRead` and `AsyncSeek` might need to
explicitly implement `bevy::asset::io::Reader` for that type.

```rust
impl bevy::asset::io::Reader for MyAsyncReadAndSeek {}
```
2024-07-01 19:59:42 +00:00
Lura
856b39d821
Apply Clippy lints regarding lazy evaluation and closures (#14015)
# Objective

- Lazily evaluate
[default](https://rust-lang.github.io/rust-clippy/master/index.html#/unwrap_or_default)~~/[or](https://rust-lang.github.io/rust-clippy/master/index.html#/or_fun_call)~~
values where it makes sense
  - ~~`unwrap_or(foo())` -> `unwrap_or_else(|| foo())`~~
  - `unwrap_or(Default::default())` -> `unwrap_or_default()`
  - etc.
- Avoid creating [redundant
closures](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure),
even for [method
calls](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure_for_method_calls)
  - `map(|something| something.into())` -> `map(Into:into)`

## Solution

- Apply Clippy lints:
-
~~[or_fun_call](https://rust-lang.github.io/rust-clippy/master/index.html#/or_fun_call)~~
-
[unwrap_or_default](https://rust-lang.github.io/rust-clippy/master/index.html#/unwrap_or_default)
-
[redundant_closure_for_method_calls](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure_for_method_calls)
([redundant
closures](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure)
is already enabled)

## Testing

- Tested on Windows 11 (`stable-x86_64-pc-windows-gnu`, 1.79.0)
- Bevy compiles without errors or warnings and examples seem to work as
intended
  - `cargo clippy` 
  - `cargo run -p ci -- compile` 

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-07-01 15:54:40 +00:00
Aztro
6dcff2bfe8
Mouse input accumulation (#14044)
# Objective

- Add the `AccumulatedMouseMotion` and `AccumulatedMouseScroll`
resources to make it simpler to track mouse motion/scroll changes
- Closes #13915

## Solution

- Created two resources, `AccumulatedMouseMotion` and
`AccumulatedMouseScroll`, and a method that tracks the `MouseMotion` and
`MouseWheel` events and accumulates their deltas every frame.
- Also modified the mouse input example to show how to use the
resources.

## Testing

- Tested the changes by modifying an existing example to use the newly
added resources, and moving/scrolling my trackpad around a ton.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-07-01 14:27:21 +00:00
Gino Valente
276dd04001
bevy_reflect: Function reflection (#13152)
# Objective

We're able to reflect types sooooooo... why not functions?

The goal of this PR is to make functions callable within a dynamic
context, where type information is not readily available at compile
time.

For example, if we have a function:

```rust
fn add(left: i32, right: i32) -> i32 {
  left + right
}
```

And two `Reflect` values we've already validated are `i32` types:

```rust
let left: Box<dyn Reflect> = Box::new(2_i32);
let right: Box<dyn Reflect> = Box::new(2_i32);
```

We should be able to call `add` with these values:

```rust
// ?????
let result: Box<dyn Reflect> = add.call_dynamic(left, right);
```

And ideally this wouldn't just work for functions, but methods and
closures too!

Right now, users have two options:

1. Manually parse the reflected data and call the function themselves
2. Rely on registered type data to handle the conversions for them

For a small function like `add`, this isn't too bad. But what about for
more complex functions? What about for many functions?

At worst, this process is error-prone. At best, it's simply tedious.

And this is assuming we know the function at compile time. What if we
want to accept a function dynamically and call it with our own
arguments?

It would be much nicer if `bevy_reflect` could alleviate some of the
problems here.

## Solution

Added function reflection!

This adds a `DynamicFunction` type to wrap a function dynamically. This
can be called with an `ArgList`, which is a dynamic list of
`Reflect`-containing `Arg` arguments. It returns a `FunctionResult`
which indicates whether or not the function call succeeded, returning a
`Reflect`-containing `Return` type if it did succeed.

Many functions can be converted into this `DynamicFunction` type thanks
to the `IntoFunction` trait.

Taking our previous `add` example, this might look something like
(explicit types added for readability):

```rust
fn add(left: i32, right: i32) -> i32 {
  left + right
}

let mut function: DynamicFunction = add.into_function();
let args: ArgList = ArgList::new().push_owned(2_i32).push_owned(2_i32);
let result: Return = function.call(args).unwrap();
let value: Box<dyn Reflect> = result.unwrap_owned();
assert_eq!(value.take::<i32>().unwrap(), 4);
```

And it also works on closures:

```rust
let add = |left: i32, right: i32| left + right;

let mut function: DynamicFunction = add.into_function();
let args: ArgList = ArgList::new().push_owned(2_i32).push_owned(2_i32);
let result: Return = function.call(args).unwrap();
let value: Box<dyn Reflect> = result.unwrap_owned();
assert_eq!(value.take::<i32>().unwrap(), 4);
```

As well as methods:

```rust
#[derive(Reflect)]
struct Foo(i32);

impl Foo {
  fn add(&mut self, value: i32) {
    self.0 += value;
  }
}

let mut foo = Foo(2);

let mut function: DynamicFunction = Foo::add.into_function();
let args: ArgList = ArgList::new().push_mut(&mut foo).push_owned(2_i32);
function.call(args).unwrap();
assert_eq!(foo.0, 4);
```

### Limitations

While this does cover many functions, it is far from a perfect system
and has quite a few limitations. Here are a few of the limitations when
using `IntoFunction`:

1. The lifetime of the return value is only tied to the lifetime of the
first argument (useful for methods). This means you can't have a
function like `(a: i32, b: &i32) -> &i32` without creating the
`DynamicFunction` manually.
2. Only 15 arguments are currently supported. If the first argument is a
(mutable) reference, this number increases to 16.
3. Manual implementations of `Reflect` will need to implement the new
`FromArg`, `GetOwnership`, and `IntoReturn` traits in order to be used
as arguments/return types.

And some limitations of `DynamicFunction` itself:

1. All arguments share the same lifetime, or rather, they will shrink to
the shortest lifetime.
2. Closures that capture their environment may need to have their
`DynamicFunction` dropped before accessing those variables again (there
is a `DynamicFunction::call_once` to make this a bit easier)
3. All arguments and return types must implement `Reflect`. While not a
big surprise coming from `bevy_reflect`, this implementation could
actually still work by swapping `Reflect` out with `Any`. Of course,
that makes working with the arguments and return values a bit harder.
4. Generic functions are not supported (unless they have been manually
monomorphized)

And general, reflection gotchas:

1. `&str` does not implement `Reflect`. Rather, `&'static str`
implements `Reflect` (the same is true for `&Path` and similar types).
This means that `&'static str` is considered an "owned" value for the
sake of generating arguments. Additionally, arguments and return types
containing `&str` will assume it's `&'static str`, which is almost never
the desired behavior. In these cases, the only solution (I believe) is
to use `&String` instead.

### Followup Work

This PR is the first of two PRs I intend to work on. The second PR will
aim to integrate this new function reflection system into the existing
reflection traits and `TypeInfo`. The goal would be to register and call
a reflected type's methods dynamically.

I chose not to do that in this PR since the diff is already quite large.
I also want the discussion for both PRs to be focused on their own
implementation.

Another followup I'd like to do is investigate allowing common container
types as a return type, such as `Option<&[mut] T>` and `Result<&[mut] T,
E>`. This would allow even more functions to opt into this system. I
chose to not include it in this one, though, for the same reasoning as
previously mentioned.

### Alternatives

One alternative I had considered was adding a macro to convert any
function into a reflection-based counterpart. The idea would be that a
struct that wraps the function would be created and users could specify
which arguments and return values should be `Reflect`. It could then be
called via a new `Function` trait.

I think that could still work, but it will be a fair bit more involved,
requiring some slightly more complex parsing. And it of course is a bit
more work for the user, since they need to create the type via macro
invocation.

It also makes registering these functions onto a type a bit more
complicated (depending on how it's implemented).

For now, I think this is a fairly simple, yet powerful solution that
provides the least amount of friction for users.

---

## Showcase

Bevy now adds support for storing and calling functions dynamically
using reflection!

```rust
// 1. Take a standard Rust function
fn add(left: i32, right: i32) -> i32 {
  left + right
}

// 2. Convert it into a type-erased `DynamicFunction` using the `IntoFunction` trait
let mut function: DynamicFunction = add.into_function();
// 3. Define your arguments from reflected values
let args: ArgList = ArgList::new().push_owned(2_i32).push_owned(2_i32);
// 4. Call the function with your arguments
let result: Return = function.call(args).unwrap();
// 5. Extract the return value
let value: Box<dyn Reflect> = result.unwrap_owned();
assert_eq!(value.take::<i32>().unwrap(), 4);
```

## Changelog

#### TL;DR

- Added support for function reflection
- Added a new `Function Reflection` example:
ba727898f2/examples/reflection/function_reflection.rs (L1-L157)

#### Details

Added the following items:

- `ArgError` enum
- `ArgId` enum
- `ArgInfo` struct
- `ArgList` struct
- `Arg` enum
- `DynamicFunction` struct
- `FromArg` trait (derived with `derive(Reflect)`)
- `FunctionError` enum
- `FunctionInfo` struct
- `FunctionResult` alias
- `GetOwnership` trait (derived with `derive(Reflect)`)
- `IntoFunction` trait (with blanket implementation)
- `IntoReturn` trait (derived with `derive(Reflect)`)
- `Ownership` enum
- `ReturnInfo` struct
- `Return` enum

---------

Co-authored-by: Periwink <charlesbour@gmail.com>
2024-07-01 13:49:08 +00:00
IceSentry
011f71a245
Update ui_material example to be a slider instead (#14031)
# Objective

- Some people have asked how to do image masking in UI. It's pretty easy
to do using a `UiMaterial` assuming you know how to write shaders.

## Solution

- Update the ui_material example to show the bevy banner slowly being
revealed like a progress bar

## Notes

I'm not entirely sure if we want this or not. For people that would be
comfortable to use this for their own games they would probably have
already figured out how to do it and for people that aren't familiar
with shaders this isn't really enough to make an actual slider/progress
bar.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2024-06-27 21:23:04 +00:00
Patrick Walton
44db8b7fac
Allow phase items not associated with meshes to be binned. (#14029)
As reported in #14004, many third-party plugins, such as Hanabi, enqueue
entities that don't have meshes into render phases. However, the
introduction of indirect mode added a dependency on mesh-specific data,
breaking this workflow. This is because GPU preprocessing requires that
the render phases manage indirect draw parameters, which don't apply to
objects that aren't meshes. The existing code skips over binned entities
that don't have indirect draw parameters, which causes the rendering to
be skipped for such objects.

To support this workflow, this commit adds a new field,
`non_mesh_items`, to `BinnedRenderPhase`. This field contains a simple
list of (bin key, entity) pairs. After drawing batchable and unbatchable
objects, the non-mesh items are drawn one after another. Bevy itself
doesn't enqueue any items into this list; it exists solely for the
application and/or plugins to use.

Additionally, this commit switches the asset ID in the standard bin keys
to be an untyped asset ID rather than that of a mesh. This allows more
flexibility, allowing bins to be keyed off any type of asset.

This patch adds a new example, `custom_phase_item`, which simultaneously
serves to demonstrate how to use this new feature and to act as a
regression test so this doesn't break again.

Fixes #14004.

## Changelog

### Added

* `BinnedRenderPhase` now contains a `non_mesh_items` field for plugins
to add custom items to.
2024-06-27 16:13:03 +00:00
François Mockers
ee63cf45c6
fix examples color_grading and mobile after BackgroundColor changes (#14033)
# Objective

- #14017 changed how `UiImage` and `BackgroundColor` work
- one change was missed in example `color_grading`, another in the
mobile example

## Solution

- Change it in the examples
2024-06-26 12:54:23 +00:00
Alice Cecile
336fddb101
Make default behavior for BackgroundColor and BorderColor more intuitive (#14017)
# Objective

In Bevy 0.13, `BackgroundColor` simply tinted the image of any
`UiImage`. This was confusing: in every other case (e.g. Text), this
added a solid square behind the element. #11165 changed this, but
removed `BackgroundColor` from `ImageBundle` to avoid confusion, since
the semantic meaning had changed.

However, this resulted in a serious UX downgrade / inconsistency, as
this behavior was no longer part of the bundle (unlike for `TextBundle`
or `NodeBundle`), leaving users with a relatively frustrating upgrade
path.

Additionally, adding both `BackgroundColor` and `UiImage` resulted in a
bizarre effect, where the background color was seemingly ignored as it
was covered by a solid white placeholder image.

Fixes #13969.

## Solution

Per @viridia's design:

> - if you don't specify a background color, it's transparent.
> - if you don't specify an image color, it's white (because it's a
multiplier).
> - if you don't specify an image, no image is drawn.
> - if you specify both a background color and an image color, they are
independent.
> - the background color is drawn behind the image (in whatever pixels
are transparent)

As laid out by @benfrankel, this involves:

1. Changing the default `UiImage` to use a transparent texture but a
pure white tint.
2. Adding `UiImage::solid_color` to quickly set placeholder images.
3. Changing the default `BorderColor` and `BackgroundColor` to
transparent.
4. Removing the default overrides for these values in the other assorted
UI bundles.
5. Adding `BackgroundColor` back to `ImageBundle` and `ButtonBundle`.
6. Adding a 1x1 `Image::transparent`, which can be accessed from
`Assets<Image>` via the `TRANSPARENT_IMAGE_HANDLE` constant.

Huge thanks to everyone who helped out with the design in the linked
issue and [the Discord
thread](https://discord.com/channels/691052431525675048/1255209923890118697/1255209999278280844):
this was very much a joint design.

@cart helped me figure out how to set the UiImage's default texture to a
transparent 1x1 image, which is a much nicer fix.

## Testing

I've checked the examples modified by this PR, and the `ui` example as
well just to be sure.

## Migration Guide

- `BackgroundColor` no longer tints the color of images in `ImageBundle`
or `ButtonBundle`. Set `UiImage::color` to tint images instead.
- The default texture for `UiImage` is now a transparent white square.
Use `UiImage::solid_color` to quickly draw debug images.
- The default value for `BackgroundColor` and `BorderColor` is now
transparent. Set the color to white manually to return to previous
behavior.
2024-06-25 21:50:41 +00:00
theotherphil
6ec1f3e6f8
Add example enum Component usage to ecs_guide (#13777)
# Objective

Add example of an enum Component to ecs_guide.

Fixes https://github.com/bevyengine/bevy/issues/11344.

## Solution

Extended ecs_guide "game" to include an enum tracking whether a player
is on a "hot" or "cold" streak.

## Testing

Ran example manually.


cc @MrGVSV
2024-06-25 12:57:11 +00:00
mgi388
9cb9969793
Use CameraController in 3d_gizmos example (#13973)
# Objective

- Make it easier to see how the 3d gizmos work by letting the viewer
control the camera.
- This was suggested by someone in Discord or in a GitHub comment but I
couldn't find the original source. I thought it was a good idea too so
decided to make a PR.

## Solution

- Use the camera controller helper instead of the automatic rotation
system.

## Testing

```
cargo run --example 3d_gizmos
```

And confirmed the freecam controls work.

### Screenshots

Initial view:

<img width="1920" alt="image"
src="https://github.com/bevyengine/bevy/assets/135186256/98672539-de4a-4eb7-98e6-c7bd03cd8d66">

Above:

<img width="1920" alt="image"
src="https://github.com/bevyengine/bevy/assets/135186256/10eabc4a-bded-44b7-a1de-6130754c7f0e">

Below:

<img width="1920" alt="image"
src="https://github.com/bevyengine/bevy/assets/135186256/b9ba9eb7-d1e8-4ad7-a9cd-aeb499ea7f9a">

Co-authored-by: mgi388 <>
2024-06-25 12:57:03 +00:00
Rob Parrett
e46e246581
Fix a few "repeated word" typos (#13955)
# Objective

Stumbled on one of these and went digging for more

## Solution

```diff
- word word
+ word
```
2024-06-20 21:35:20 +00:00
Rob Parrett
c66c2c7420
Omit font size where it closely matches the default in examples (#13952)
# Objective

In a few examples, we're specifying a font or font size that is the same
as the current default value. Might as well use the default. That'll be
one less thing to worry about if we ever need to change the default font
size. (wink)

In a few others, we were using a value of `25.0` and it didn't seem like
it was different for an important reason, so I switched to the default
there too.

(There are a bunch of examples that use non-default font sizes for
various reasons. Not trying address them all here.)
2024-06-20 21:01:28 +00:00
Rob Parrett
c110b10367
Use default window and font sizes in sprite_slice example (#13951)
# Objective

A couple issues with this example are evident from this screenshot of
the example showcase:

<img width="319" alt="image"
src="https://github.com/bevyengine/bevy/assets/200550/5325bb29-9576-4989-a5a3-a972c8bbf1af">

- The images are misaligned, closer to the right edge of the screen
- The example uses a custom window resolution with a different aspect
ratio from the default, which results in black bars

## Solution

- Use the default window size
- Adjust positions so that things are centered

This isn't really fixing a problem, but I also:

- Used the default font size and adjusted the text labels and gaps so
that everything still fits

Which is how I got here in the first place (one less font size to adjust
for the cosmic text PR).

## Before

<img width="1350" alt="Screenshot 2024-06-20 at 12 23 10 PM"
src="https://github.com/bevyengine/bevy/assets/200550/1c7cfcfe-7edc-4561-a4e7-9b3bc8f87f75">

## After

<img width="1280" alt="Screenshot 2024-06-20 at 12 23 30 PM"
src="https://github.com/bevyengine/bevy/assets/200550/abab8a46-4e11-4ee6-a407-ae3b8bf31975">
2024-06-20 19:40:38 +00:00
Chris Biscardi
4d3f43131e
Use a ship in Transform::align example (#13935)
# Objective

The documentation for
[`Transform::align`](https://docs.rs/bevy/0.14.0-rc.3/bevy/transform/components/struct.Transform.html#method.align)
mentions a hypothetical ship model. Showing this concretely would be a
nice improvement over using a cube.

> For example, if a spaceship model has its nose pointing in the
X-direction in its own local coordinates and its dorsal fin pointing in
the Y-direction, then align(Dir3::X, v, Dir3::Y, w) will make the
spaceship’s nose point in the direction of v, while the dorsal fin does
its best to point in the direction w.


## Solution

This commit makes the ship less hypothetical by using a kenney ship
model in the example.

The local axes for the ship needed to change to accommodate the gltf, so
the hypothetical in the documentation and this example's local axes
don't necessarily match. Docs use `align(Dir3::X, v, Dir3::Y, w)` and
this example now uses `(Vec3::NEG_Z, *first, Vec3::X, *second)`.

I manually modified the `craft_speederD` Node's `translation` to be
0,0,0 in the gltf file, which means it now differs from kenney's
original model.

Original ship from: https://kenney.nl/assets/space-kit

## Testing

```
cargo run --example align
```

![screenshot-2024-06-19-at-14 27
05@2x](https://github.com/bevyengine/bevy/assets/551247/ab1afc8f-76b2-42b6-b455-f0d1c77cfed7)
![screenshot-2024-06-19-at-14 27
12@2x](https://github.com/bevyengine/bevy/assets/551247/4a01031c-4ea1-43ab-8078-3656db67efe0)
![screenshot-2024-06-19-at-14 27
20@2x](https://github.com/bevyengine/bevy/assets/551247/06830f38-ba2b-4e3a-a265-2d10f9ea9de9)
2024-06-20 00:58:00 +00:00
MiniaczQ
31af724944
Move StateTransitionSteps registration to states plugin (#13939)
# Objective

Fixes #13920

## Solution

As described in the issue.

## Testing

Moved a custom transition plugin in example before any of the app-state
methods.
2024-06-20 00:57:40 +00:00
Chris Biscardi
20eb13f458
Use smooth_nudge in 2d_top_down_camera example (#13907)
# Objective


[`StableInterpolate`](https://dev-docs.bevyengine.org/bevy/math/trait.StableInterpolate.html)
was introduced after this example was written (or more accurately, the
two PRs were merged on the same day and developed in parallel).

The example used `Vec3::lerp` where I believe it is now preferred to use
`smooth_nudge`.

## Solution

Its not entirely clear to me whether `StableInterpolate` should be
preferred in this scenario, although it seems likely. So I figured a PR
to make the change would either result in it being merged or denied with
a reason.

## Testing

```
cargo run --example 2d_top_down_camera
```

Co-authored-by: François Mockers <mockersf@gmail.com>
2024-06-18 11:38:17 +00:00
Jan Hohenheim
6273227e09
Fix lints introduced in Rust beta 1.80 (#13899)
Resolves #13895

Mostly just involves being more explicit about which parts of the docs
belong to a list and which begin a new paragraph.
- found a few docs that were malformed because of exactly this, so I
fixed that by introducing a paragraph
- added indentation to nearly all multiline lists
- fixed a few minor typos
- added `#[allow(dead_code)]` to types that are needed to test
annotations but are never constructed
([here](https://github.com/bevyengine/bevy/pull/13899/files#diff-b02b63604e569c8577c491e7a2030d456886d8f6716eeccd46b11df8aac75dafR1514)
and
[here](https://github.com/bevyengine/bevy/pull/13899/files#diff-b02b63604e569c8577c491e7a2030d456886d8f6716eeccd46b11df8aac75dafR1523))
- verified that  `cargo +beta run -p ci -- lints` passes
- verified that `cargo +beta run -p ci -- test` passes
2024-06-17 17:22:01 +00:00
Ľubomír Kurčák
4b3246af40
Add cross gizmos (#13883)
# Objective

Add `cross` and `cross_2d` gizmos in accordance with #13868.

## Solution

Extend `Gizmos` to provide these functions.

## Testing

Tested in `2d_gizmos` and `3d_gizmos` examples, and external projects.


![image](https://github.com/bevyengine/bevy/assets/29227697/d13067e1-d7eb-46c5-9b73-6c2d70417889)


![image](https://github.com/bevyengine/bevy/assets/29227697/0a8eba48-fbb3-4b3e-abe1-4e250222f94b)
2024-06-17 15:45:32 +00:00
Jan Hohenheim
48f70789f5
Add first person view model example (#13828)
# Objective

A very common way to organize a first-person view is to split it into
two kinds of models:

 - The *view model* is the model that represents the player's body.
 - The *world model* is everything else.

The reason for this distinction is that these two models should be
rendered with different FOVs.
The view model is typically designed and animated with a very specific
FOV in mind, so it is
generally *fixed* and cannot be changed by a player. The world model, on
the other hand, should
be able to change its FOV to accommodate the player's preferences for
the following reasons:
- *Accessibility*: How prone is the player to motion sickness? A wider
FOV can help.
- *Tactical preference*: Does the player want to see more of the
battlefield?
 Or have a more zoomed-in view for precision aiming?
- *Physical considerations*: How well does the in-game FOV match the
player's real-world FOV?
Are they sitting in front of a monitor or playing on a TV in the living
room? How big is the screen?

## Solution

I've added an example implementing the described setup as follows.

The `Player` is an entity holding two cameras, one for each model. The
view model camera has a fixed
FOV of 70 degrees, while the world model camera has a variable FOV that
can be changed by the player.

 I use different `RenderLayers` to select what to render.

- The world model camera has no explicit `RenderLayers` component, so it
uses the layer 0.
All static objects in the scene are also on layer 0 for the same reason.
- The view model camera has a `RenderLayers` component with layer 1, so
it only renders objects
explicitly assigned to layer 1. The arm of the player is one such
object.
The order of the view model camera is additionally bumped to 1 to ensure
it renders on top of the world model.
- The light source in the scene must illuminate both the view model and
the world model, so it is
 assigned to both layers 0 and 1.

To better see the effect, the player can move the camera by dragging
their mouse and change the world model's FOV with the arrow keys. The
arrow up key maps to "decrease FOV" and the arrow down key maps to
"increase FOV". This sounds backwards on paper, but is more intuitive
when actually changing the FOV in-game since a decrease in FOV looks
like a zoom-in.
I intentionally do not allow changing the view model's FOV even though
it would be illustrative because that would be an anti-pattern and bloat
the code a bit.

The example is called `first_person_view_model` and not just
`first_person` because I want to highlight that this is not a simple
flycam, but actually renders the player.

## Testing

Default FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/8c2e804f-fac2-48c7-8a22-d85af999dfb2">

Decreased FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/1733b3e5-f583-4214-a454-3554e3cbd066">

Increased FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/0b0640e6-5743-46f6-a79a-7181ba9678e8">

Note that the white bar on the right represents the player's arm, which
is more obvious in-game because you can move the camera around.
The box on top is there to make sure that the view model is receiving
shadows.

I tested only on macOS.

---

## Changelog

I don't think new examples go in here, do they?

## Caveat

The solution used here was implemented with help by @robtfm on
[Discord](https://discord.com/channels/691052431525675048/866787577687310356/1241019224491561000):
> shadow maps are specific to lights, not to layers
> if you want shadows from some meshes that are not visible, you could
have light on layer 1+2, meshes on layer 2, camera on layer 1 (for
example)
> but this might change in future, it's not exactly an intended feature

In other words, the example code as-is is not guaranteed to work in the
future. I want to bring this up because the use-case presented here is
extremely common in first-person games and important for accessibility.
It would be good to have a blessed and easy way of how to achieve it.

I'm also not happy about how I get the `perspective` variable in
`change_fov`. Very open to suggestions :)

## Related issues

- Addresses parts of #12658
- Addresses parts of #12588

---------

Co-authored-by: Pascal Hertleif <killercup@gmail.com>
2024-06-17 15:03:31 +00:00
François Mockers
8b38299bd4
observers example doesn't follow standards (#13884)
# Objective

- Observers example is using an unseeded random, prints text to console
and doesn't display text as other examples

## Solution

- use seeded random
- log instead of printing
- use common settings for UI text
2024-06-17 00:34:08 +00:00
James O'Brien
eb3c81374a
Generalised ECS reactivity with Observers (#10839)
# Objective

- Provide an expressive way to register dynamic behavior in response to
ECS changes that is consistent with existing bevy types and traits as to
provide a smooth user experience.
- Provide a mechanism for immediate changes in response to events during
command application in order to facilitate improved query caching on the
path to relations.

## Solution

- A new fundamental ECS construct, the `Observer`; inspired by flec's
observers but adapted to better fit bevy's access patterns and rust's
type system.

---

## Examples
There are 3 main ways to register observers. The first is a "component
observer" that looks like this:
```rust
world.observe(|trigger: Trigger<OnAdd, Transform>, query: Query<&Transform>| {
    let transform = query.get(trigger.entity()).unwrap();
});
```
The above code will spawn a new entity representing the observer that
will run it's callback whenever the `Transform` component is added to an
entity. This is a system-like function that supports dependency
injection for all the standard bevy types: `Query`, `Res`, `Commands`
etc. It also has a `Trigger` parameter that provides information about
the trigger such as the target entity, and the event being triggered.
Importantly these systems run during command application which is key
for their future use to keep ECS internals up to date. There are similar
events for `OnInsert` and `OnRemove`, and this will be expanded with
things such as `ArchetypeCreated`, `TableEmpty` etc. in follow up PRs.

Another way to register an observer is an "entity observer" that looks
like this:
```rust
world.entity_mut(entity).observe(|trigger: Trigger<Resize>| {
    // ...
});
```
Entity observers run whenever an event of their type is triggered
targeting that specific entity. This type of observer will de-spawn
itself if the entity (or entities) it is observing is ever de-spawned so
as to not leave dangling observers.

Entity observers can also be spawned from deferred contexts such as
other observers, systems, or hooks using commands:
```rust
commands.entity(entity).observe(|trigger: Trigger<Resize>| {
    // ...
});
```

Observers are not limited to in built event types, they can be used with
any type that implements `Event` (which has been extended to implement
Component). This means events can also carry data:

```rust
#[derive(Event)]
struct Resize { x: u32, y: u32 }

commands.entity(entity).observe(|trigger: Trigger<Resize>, query: Query<&mut Size>| {
    let event = trigger.event();
    // ...
});

// Will trigger the observer when commands are applied.
commands.trigger_targets(Resize { x: 10, y: 10 }, entity);
```

You can also trigger events that target more than one entity at a time:

```rust
commands.trigger_targets(Resize { x: 10, y: 10 }, [e1, e2]);
```

Additionally, Observers don't _need_ entity targets:

```rust
app.observe(|trigger: Trigger<Quit>| {
})

commands.trigger(Quit);
```

In these cases, `trigger.entity()` will be a placeholder.

Observers are actually just normal entities with an `ObserverState` and
`Observer` component! The `observe()` functions above are just shorthand
for:

```rust
world.spawn(Observer::new(|trigger: Trigger<Resize>| {});
```

This will spawn the `Observer` system and use an `on_add` hook to add
the `ObserverState` component.

Dynamic components and trigger types are also fully supported allowing
for runtime defined trigger types.

## Possible Follow-ups
1. Deprecate `RemovedComponents`, observers should fulfill all use cases
while being more flexible and performant.
2. Queries as entities: Swap queries to entities and begin using
observers listening to archetype creation triggers to keep their caches
in sync, this allows unification of `ObserverState` and `QueryState` as
well as unlocking several API improvements for `Query` and the
management of `QueryState`.
3. Trigger bubbling: For some UI use cases in particular users are
likely to want some form of bubbling for entity observers, this is
trivial to implement naively but ideally this includes an acceleration
structure to cache hierarchy traversals.
4. All kinds of other in-built trigger types.
5. Optimization; in order to not bloat the complexity of the PR I have
kept the implementation straightforward, there are several areas where
performance can be improved. The focus for this PR is to get the
behavior implemented and not incur a performance cost for users who
don't use observers.

I am leaving each of these to follow up PR's in order to keep each of
them reviewable as this already includes significant changes.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: MiniaczQ <xnetroidpl@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2024-06-15 01:33:26 +00:00
James Gayfer
061baa4ff7
Use dynamic uniform buffer in post processing example (#13540)
# Objective

While learning about shaders and pipelines, I found this example to be
misleading; it wasn't clear to me how the node knew what the correct
"instance" of `PostProcessSettings` we should send to the shader (as the
combination of `ExtractComponentPlugin` and `UniformComponentPlugin`
extracts + sends _all_ of our `PostProcessSetting` components to the
GPU).

The goal of this PR is to clarify how to target the view specific
`PostProcessSettings` in the shader when there are multiple cameras.

## Solution

To accomplish this, we can use a dynamic uniform buffer for
`PostProcessSettings`, querying for the relevant `DynamicUniformIndex`
in the `PostProcessNode` to get the relevant index to use with the bind
group.

While the example in its current state is _correct_, I believe that fact
that it's intended to showcase a per camera post processing effect
warrants a dynamic uniform buffer (even though in the context of this
example we have only one camera, and therefore no adverse behaviour).

## Testing

- Run the `post_processing` example before and after this change,
verifying they behave the same.

## Reviewer notes

This is my first PR to Bevy, and I'm by no means an expert in the world
of rendering (though I'm trying to learn all I can). If there's a better
way to do this / a reason not to take this route, I'd love to hear it!

Thanks in advance.
2024-06-14 18:04:13 +00:00
Kornel
435d9bc02c
Highlight dependency on shader files in examples (#13824)
The examples won't work when copy-pasted to another project, without
also copying their shader files. This change adds constants at the top
of the files to bring attention to the dependencies.

Follow up to
[#13624](https://github.com/bevyengine/bevy/pull/13624#issuecomment-2143872791)
2024-06-12 14:16:01 +00:00
Lynn
c172c3c4b5
Custom primitives example (#13795)
# Objective

- Add a new example showcasing how to add custom primitives and what you
can do with them.

## Solution

- Added a new example `custom_primitives` with a 2D heart shape
primitive highlighting
  - `Bounded2d` by implementing and visualising bounding shapes,
  - `Measured2d` by implementing it,
  - `Meshable` to show the shape on the screen
- The example also includes an `Extrusion<Heart>` implementing
  - `Measured3d`,
  - `Bounded3d` using the `BoundedExtrusion` trait and
  - meshing using the `Extrudable` trait.

## Additional information

Here are two images of the heart and its extrusion:

![image_2024-06-10_194631194](https://github.com/bevyengine/bevy/assets/62256001/53f1836c-df74-4ba6-85e9-fabdafa94c66)
![Screenshot 2024-06-10
194609](https://github.com/bevyengine/bevy/assets/62256001/b1630e71-6e94-4293-b7b5-da8d9cc98faf)

---------

Co-authored-by: Jakub Marcowski <37378746+Chubercik@users.noreply.github.com>
2024-06-10 21:15:21 +00:00
T.J. Given
70a38ab1f6
Re-name and Extend Run Conditions API (#13784)
# Objective

- My attempt at fulfilling #13629.

## Solution

Renames the `and_then` / `or_else` run condition methods to `and` /
`or`, respectively.

Extends the run conditions API to include a suite of binary logical
operators:
- `and`
- `or`
- `nand`
- `nor`
- `xor`
- `xnor`

## Testing

- Did you test these changes? If so, how?
- The test **run_condition_combinators** was extended to include the
added run condition combinators. A **double_counter** system was added
to test for combinators running on even count cycles.

- Are there any parts that need more testing?
- I'm not too sure how I feel about the "counter" style of testing but I
wanted to keep it consistent. If it's just a unit test I would prefer
simply to just assert `true` == _combinator output_ or `false` ==
_combinator output_ .

- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- Nothing too specific. The added methods should be equivalent to the
logical operators they are analogous to (`&&` , `||`, `^`, `!`).

- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
    - Should not be relevant, I'm using Windows.

## Changelog

- What changed as a result of this PR?
    - The run conditions API.

- If applicable, organize changes under "Added", "Changed", or "Fixed"
sub-headings
    - Changed:
        - `and_then` run condition combinator renamed to simply `and`
        - `or_else` run condition combinator renamed to simply `or`
    - Added:
        - `nand` run condition combinator.
        - `nor` run condition combinator.
        - `xor` run condition combinator.
        - `xnor` run condition combinator.

## Migration Guide

- The `and_then` run condition method has been replaced with the `and`
run condition method.
- The `or_else` run condition method has been replaced with the `or` run
condition method.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Andres O. Vela <andresovela@users.noreply.github.com>
2024-06-10 13:41:56 +00:00
MiniaczQ
6d0b7504a2
Add more granular system sets for state transition schedule ordering (#13763)
# Objective

Fixes #13711 

## Solution

Introduce smaller, generic system sets for each schedule variant, which
are ordered against other generic variants:
- `ExitSchedules<S>` - For `OnExit` schedules, runs from leaf states to
root states.
- `TransitionSchedules<S>` - For `OnTransition` schedules, runs in
arbitrary order.
- `EnterSchedules<S>` - For `OnEnter` schedules, runs from root states
to leaf states.

Also unified `ApplyStateTransition<S>` schedule which works in basically
the same way, just for internals.

## Testing

- One test that tests schedule execution order

---------

Co-authored-by: Lee-Orr <lee-orr@users.noreply.github.com>
2024-06-10 13:13:58 +00:00
Matty
a569b35c18
Stable interpolation and smooth following (#13741)
# Objective

Partially address #13408 

Rework of #13613

Unify the very nice forms of interpolation specifically present in
`bevy_math` under a shared trait upon which further behavior can be
based.

The ideas in this PR were prompted by [Lerp smoothing is broken by Freya
Holmer](https://www.youtube.com/watch?v=LSNQuFEDOyQ).

## Solution

There is a new trait `StableInterpolate` in `bevy_math::common_traits`
which enshrines a quite-specific notion of interpolation with a lot of
guarantees:
```rust
/// A type with a natural interpolation that provides strong subdivision guarantees.
///
/// Although the only required method is `interpolate_stable`, many things are expected of it:
///
/// 1. The notion of interpolation should follow naturally from the semantics of the type, so
///    that inferring the interpolation mode from the type alone is sensible.
///
/// 2. The interpolation recovers something equivalent to the starting value at `t = 0.0`
///    and likewise with the ending value at `t = 1.0`.
///
/// 3. Importantly, the interpolation must be *subdivision-stable*: for any interpolation curve
///    between two (unnamed) values and any parameter-value pairs `(t0, p)` and `(t1, q)`, the
///    interpolation curve between `p` and `q` must be the *linear* reparametrization of the original
///    interpolation curve restricted to the interval `[t0, t1]`.
///
/// The last of these conditions is very strong and indicates something like constant speed. It
/// is called "subdivision stability" because it guarantees that breaking up the interpolation
/// into segments and joining them back together has no effect.
///
/// Here is a diagram depicting it:
/// ```text
/// top curve = u.interpolate_stable(v, t)
///
///              t0 => p   t1 => q    
///   |-------------|---------|-------------|
/// 0 => u         /           \          1 => v
///              /               \
///            /                   \
///          /        linear         \
///        /     reparametrization     \
///      /   t = t0 * (1 - s) + t1 * s   \
///    /                                   \
///   |-------------------------------------|
/// 0 => p                                1 => q
///
/// bottom curve = p.interpolate_stable(q, s)
/// ```
///
/// Note that some common forms of interpolation do not satisfy this criterion. For example,
/// [`Quat::lerp`] and [`Rot2::nlerp`] are not subdivision-stable.
///
/// Furthermore, this is not to be used as a general trait for abstract interpolation.
/// Consumers rely on the strong guarantees in order for behavior based on this trait to be
/// well-behaved.
///
/// [`Quat::lerp`]: crate::Quat::lerp
/// [`Rot2::nlerp`]: crate::Rot2::nlerp
pub trait StableInterpolate: Clone {
    /// Interpolate between this value and the `other` given value using the parameter `t`.
    /// Note that the parameter `t` is not necessarily clamped to lie between `0` and `1`.
    /// When `t = 0.0`, `self` is recovered, while `other` is recovered at `t = 1.0`,
    /// with intermediate values lying between the two.
    fn interpolate_stable(&self, other: &Self, t: f32) -> Self;
}
```

This trait has a blanket implementation over `NormedVectorSpace`, where
`lerp` is used, along with implementations for `Rot2`, `Quat`, and the
direction types using variants of `slerp`. Other areas may choose to
implement this trait in order to hook into its functionality, but the
stringent requirements must actually be met.

This trait bears no direct relationship with `bevy_animation`'s
`Animatable` trait, although they may choose to use `interpolate_stable`
in their trait implementations if they wish, as both traits involve
type-inferred interpolations of the same kind. `StableInterpolate` is
not a supertrait of `Animatable` for a couple reasons:
1. Notions of interpolation in animation are generally going to be much
more general than those allowed under these constraints.
2. Laying out these generalized interpolation notions is the domain of
`bevy_animation` rather than of `bevy_math`. (Consider also that
inferring interpolation from types is not universally desirable.)

Similarly, this is not implemented on `bevy_color`'s color types,
although their current mixing behavior does meet the conditions of the
trait.

As an aside, the subdivision-stability condition is of interest
specifically for the [Curve
RFC](https://github.com/bevyengine/rfcs/pull/80), where it also ensures
a kind of stability for subsampling.

Importantly, this trait ensures that the "smooth following" behavior
defined in this PR behaves predictably:
```rust
    /// Smoothly nudge this value towards the `target` at a given decay rate. The `decay_rate`
    /// parameter controls how fast the distance between `self` and `target` decays relative to
    /// the units of `delta`; the intended usage is for `decay_rate` to generally remain fixed,
    /// while `delta` is something like `delta_time` from an updating system. This produces a
    /// smooth following of the target that is independent of framerate.
    ///
    /// More specifically, when this is called repeatedly, the result is that the distance between
    /// `self` and a fixed `target` attenuates exponentially, with the rate of this exponential
    /// decay given by `decay_rate`.
    ///
    /// For example, at `decay_rate = 0.0`, this has no effect.
    /// At `decay_rate = f32::INFINITY`, `self` immediately snaps to `target`.
    /// In general, higher rates mean that `self` moves more quickly towards `target`.
    ///
    /// # Example
    /// ```
    /// # use bevy_math::{Vec3, StableInterpolate};
    /// # let delta_time: f32 = 1.0 / 60.0;
    /// let mut object_position: Vec3 = Vec3::ZERO;
    /// let target_position: Vec3 = Vec3::new(2.0, 3.0, 5.0);
    /// // Decay rate of ln(10) => after 1 second, remaining distance is 1/10th
    /// let decay_rate = f32::ln(10.0);
    /// // Calling this repeatedly will move `object_position` towards `target_position`:
    /// object_position.smooth_nudge(&target_position, decay_rate, delta_time);
    /// ```
    fn smooth_nudge(&mut self, target: &Self, decay_rate: f32, delta: f32) {
        self.interpolate_stable_assign(target, 1.0 - f32::exp(-decay_rate * delta));
    }
```

As the documentation indicates, the intention is for this to be called
in game update systems, and `delta` would be something like
`Time::delta_seconds` in Bevy, allowing positions, orientations, and so
on to smoothly follow a target. A new example, `smooth_follow`,
demonstrates a basic implementation of this, with a sphere smoothly
following a sharply moving target:


https://github.com/bevyengine/bevy/assets/2975848/7124b28b-6361-47e3-acf7-d1578ebd0347


## Testing

Tested by running the example with various parameters.
2024-06-10 12:50:59 +00:00
Julian
33dff0d3f7
2D top-down camera example (#12720)
# Objective

This PR addresses the 2D part of #12658. I plan to separate the examples
and make one PR per camera example.

## Solution

Added a new top-down example composed of:

- [x] Player keyboard movements
- [x] UI for keyboard instructions
- [x] Colors and bloom effect to see the movement of the player
- [x] Camera smooth movement towards the player (lerp)

## Testing

```bash
cargo run --features="wayland,bevy/dynamic_linking" --example 2d_top_down_camera
```



https://github.com/bevyengine/bevy/assets/10638479/95db0587-e5e0-4f55-be11-97444b795793
2024-06-10 12:33:48 +00:00
François Mockers
95edd2ea71
async_compute example: don't block in the task (#13699)
# Objective

- Fixes #13672 

## Solution

- Don't use blocking sleep in the tasks, so that it won't block the task
pool
2024-06-06 00:21:33 +00:00
IceSentry
16207e4043
Use BufferVec for gpu_readback example (#13668)
# Objective

- Where possible, it's recommended to use `BufferVec` over
`encase::StorageBuffer` for performance reason. It doesn't really matter
for the example, but it's still important to teach the better solution.

## Solution

- Use BufferVec in the gpu_readback example
2024-06-04 19:31:44 +00:00
Lynn
fd82ef8956
Meshable extrusions (#13478)
# Objective

- Implement `Meshable` for `Extrusion<T>`

## Solution

- `Meshable` requires `Meshable::Output: MeshBuilder` now. This means
that all `some_primitive.mesh()` calls now return a `MeshBuilder`. These
were added for primitives that did not have one prior to this.
- A new trait `Extrudable: MeshBuilder` has been added. This trait
allows you to specify the indices of the perimeter of the mesh created
by this `MeshBuilder` and whether they are to be shaded smooth or flat.
- `Extrusion<P: Primitive2d + Meshable>` is now `Meshable` aswell. The
associated `MeshBuilder` is `ExtrusionMeshBuilder` which is generic over
`P` and uses the `MeshBuilder` of its baseshape internally.
- `ExtrusionMeshBuilder` exposes the configuration functions of its
base-shapes builder.
- Updated the `3d_shapes` example to include `Extrusion`s

## Migration Guide

- Depending on the context, you may need to explicitly call
`.mesh().build()` on primitives where you have previously called
`.mesh()`
- The `Output` type of custom `Meshable` implementations must now derive
`MeshBuilder`.

## Additional information
- The extrusions UVs are done so that 
- the front face (`+Z`) is in the area between `(0, 0)` and `(0.5,
0.5)`,
- the back face (`-Z`) is in the area between `(0.5, 0)` and `(1, 0.5)`
- the mantle is in the area between `(0, 0.5)` and `(1, 1)`. Each
`PerimeterSegment` you specified in the `Extrudable` implementation will
be allocated an equal portion of this area.
- The UVs of the base shape are scaled to be in the front/back area so
whatever method of filling the full UV-space the base shape used is how
these areas will be filled.

Here is an example of what that looks like on a capsule:


https://github.com/bevyengine/bevy/assets/62256001/425ad288-fbbc-4634-9d3f-5e846cdce85f

This is the texture used:

![extrusion
uvs](https://github.com/bevyengine/bevy/assets/62256001/4e54e421-bfda-44b9-8571-412525cebddf)

The `3d_shapes` example now looks like this:


![image_2024-05-22_235915753](https://github.com/bevyengine/bevy/assets/62256001/3d8bc86d-9ed1-47f2-899a-27aac0a265dd)

---------

Co-authored-by: Lynn Büttgenbach <62256001+solis-lumine-vorago@users.noreply.github.com>
Co-authored-by: Matty <weatherleymatthew@gmail.com>
Co-authored-by: Matty <2975848+mweatherley@users.noreply.github.com>
2024-06-04 17:27:32 +00:00
Patrick Walton
ace4c6023b
Implement subpixel morphological antialiasing, or SMAA. (#13423)
This commit implements a large subset of [*subpixel morphological
antialiasing*], better known as SMAA. SMAA is a 2011 antialiasing
technique that detects jaggies in an aliased image and smooths them out.
Despite its age, it's been a continual staple of games for over a
decade. Four quality presets are available: *low*, *medium*, *high*, and
*ultra*. I set the default to *high*, on account of modern GPUs being
significantly faster than they were in 2011.

Like the already-implemented FXAA, SMAA works on an unaliased image.
Unlike FXAA, it requires three passes: (1) edge detection; (2) blending
weight calculation; (3) neighborhood blending. Each of the first two
passes writes an intermediate texture for use by the next pass. The
first pass also writes to a stencil buffer in order to dramatically
reduce the number of pixels that the second pass has to examine. Also
unlike FXAA, two built-in lookup textures are required; I bundle them
into the library in compressed KTX2 format.

The [reference implementation of SMAA] is in HLSL, with abundant use of
preprocessor macros to achieve GLSL compatibility. Unfortunately, the
reference implementation predates WGSL by over a decade, so I had to
translate the HLSL to WGSL manually. As much as was reasonably possible
without sacrificing readability, I tried to translate line by line,
preserving comments, both to aid reviewing and to allow patches to the
HLSL to more easily apply to the WGSL. Most of SMAA's features are
supported, but in the interests of making this patch somewhat less huge,
I skipped a few of the more exotic ones:

* The temporal variant is currently unsupported. This is and has been
used in shipping games, so supporting temporal SMAA would be useful
follow-up work. It would, however, require some significant work on TAA
to ensure compatibility, so I opted to skip it in this patch.

* Depth- and chroma-based edge detection are unimplemented; only luma
is. Depth is lower-quality, but faster; chroma is higher-quality, but
slower. Luma is the suggested default edge detection algorithm. (Note
that depth-based edge detection wouldn't work on WebGL 2 anyway, because
of the Naga bug whereby depth sampling is miscompiled in GLSL. This is
the same bug that prevents depth of field from working on that
platform.)

* Predicated thresholding is currently unsupported.

* My implementation is incompatible with SSAA and MSAA, unlike the
original; MSAA must be turned off to use SMAA in Bevy. I believe this
feature was rarely used in practice.

The `anti_aliasing` example has been updated to allow experimentation
with and testing of the different SMAA quality presets. Along the way, I
refactored the example's help text rendering code a bit to eliminate
code repetition.

SMAA is fully supported on WebGL 2.

Fixes #9819.

[*subpixel morphological antialiasing*]: https://www.iryoku.com/smaa/

[reference implementation of SMAA]: https://github.com/iryoku/smaa

## Changelog

### Added

* Subpixel morphological antialiasing, or SMAA, is now available. To use
it, add the `SmaaSettings` component to your `Camera`.

![Screenshot 2024-05-18
134311](https://github.com/bevyengine/bevy/assets/157897/ffbd611c-1b32-4491-b2e2-e410688852ee)

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-06-04 17:07:34 +00:00
MiniaczQ
49338245ea
Generalize StateTransitionEvent<S> to allow identity transitions (#13579)
# Objective

This PR addresses one of the issues from [discord state
discussion](https://discord.com/channels/691052431525675048/1237949214017716356).
Same-state transitions can be desirable, so there should exist a hook
for them.

Fixes https://github.com/bevyengine/bevy/issues/9130.

## Solution

- Allow `StateTransitionEvent<S>` to contain identity transitions.
- Ignore identity transitions at schedule running level (`OnExit`,
`OnTransition`, `OnEnter`).
- Propagate identity transitions through `SubStates` and
`ComputedStates`.
- Add example about registering custom transition schedules.

## Changelog

- `StateTransitionEvent<S>` can be emitted with same `exited` and
`entered` state.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-06-04 14:23:24 +00:00
François Mockers
df57850310
rename touchpad to gesture, and add new gestures (#13660)
# Objective

- With the recent winit update, touchpad specific events can also be
triggered on mobile

## Solution

- Rename them to gestures and add support for the new ones

## Testing

- Tested on the mobile example on iOS


https://github.com/bevyengine/bevy/assets/8672791/da4ed23f-ff0a-41b2-9dcd-726e8546bef2


## Migration Guide

- `TouchpadMagnify` has been renamed to `PinchGesture`
- `TouchpadRotate` has been renamed to `RotationGesture `

---------

Co-authored-by: mike <ramirezmike2@gmail.com>
2024-06-04 12:44:25 +00:00
MiniaczQ
58a0c1336c
Move utilities from examples to bevy_state and add concept of state-scoped entities (#13649)
# Objective

Move `StateScoped` and `log_transitions` to `bevy_state`, since they're
useful for end users.

Addresses #12852, although not in the way the issue had in mind.

## Solution

- Added `bevy_hierarchy` to default features of `bevy_state`.
- Move `log_transitions` to `transitions` module.
- Move `StateScoped` to `state_scoped` module, gated behind
`bevy_hierarchy` feature.
- Refreshed implementation.
- Added `enable_state_coped_entities<S: States>()` to add required
machinery to `App` for clearing state-scoped entities.


## Changelog

- Added `log_transitions` for displaying state transitions.
- Added `StateScoped` for binding entity lifetime to state and app
`enable_state_coped_entities` to register cleaning behavior.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François Mockers <francois.mockers@vleue.com>
2024-06-04 11:44:34 +00:00
Patrick Walton
ad6872275f
Rename "point light" to "clusterable object" in cluster contexts. (#13654)
We want to use the clustering infrastructure for light probes and decals
as well, not just point lights. This patch builds on top of #13640 and
performs the rename.

To make this series easier to review, this patch makes no code changes.
Only identifiers and comments are modified.

## Migration Guide

* In the PBR shaders, `point_lights` is now known as
`clusterable_objects`, `PointLight` is now known as `ClusterableObject`,
and `cluster_light_index_lists` is now known as
`clusterable_object_index_lists`.
2024-06-04 11:01:13 +00:00