# Objective
Now that #13432 has been merged, it's important we update our reflected
types to properly opt into this feature. If we do not, then this could
cause issues for users downstream who want to make use of
reflection-based cloning.
## Solution
This PR is broken into 4 commits:
1. Add `#[reflect(Clone)]` on all types marked `#[reflect(opaque)]` that
are also `Clone`. This is mandatory as these types would otherwise cause
the cloning operation to fail for any type that contains it at any
depth.
2. Update the reflection example to suggest adding `#[reflect(Clone)]`
on opaque types.
3. Add `#[reflect(clone)]` attributes on all fields marked
`#[reflect(ignore)]` that are also `Clone`. This prevents the ignored
field from causing the cloning operation to fail.
Note that some of the types that contain these fields are also `Clone`,
and thus can be marked `#[reflect(Clone)]`. This makes the
`#[reflect(clone)]` attribute redundant. However, I think it's safer to
keep it marked in the case that the `Clone` impl/derive is ever removed.
I'm open to removing them, though, if people disagree.
4. Finally, I added `#[reflect(Clone)]` on all types that are also
`Clone`. While not strictly necessary, it enables us to reduce the
generated output since we can just call `Clone::clone` directly instead
of calling `PartialReflect::reflect_clone` on each variant/field. It
also means we benefit from any optimizations or customizations made in
the `Clone` impl, including directly dereferencing `Copy` values and
increasing reference counters.
Along with that change I also took the liberty of adding any missing
registrations that I saw could be applied to the type as well, such as
`Default`, `PartialEq`, and `Hash`. There were hundreds of these to
edit, though, so it's possible I missed quite a few.
That last commit is **_massive_**. There were nearly 700 types to
update. So it's recommended to review the first three before moving onto
that last one.
Additionally, I can break the last commit off into its own PR or into
smaller PRs, but I figured this would be the easiest way of doing it
(and in a timely manner since I unfortunately don't have as much time as
I used to for code contributions).
## Testing
You can test locally with a `cargo check`:
```
cargo check --workspace --all-features
```
# Objective
Add a `UiRect::AUTO` const which is a `UiRect` with all its edge values
set to `Val::Auto`.
IIRC `UiRect`'s default for its fields a few versions ago was
`Val::Auto` because positions were represented using a `UiRect` and they
required `Val::Auto` as a default. Then when position was split up and
the `UiRect` default was changed, we forgot add a `UiRect::AUTO` const.
# Objective
- `ValArithmeticError` contains a typo, and one of it's variants is not
used
## Solution
- Rename `NonEvaluateable::NonEvaluateable ` variant to
`NonEvaluateable::NonEvaluable`.
- Remove variant `ValArithmeticError:: NonIdenticalVariants`.
## Testing
- `cargo run -p ci`
---
## Migration Guide
- `ValArithmeticError::NonEvaluateable` has been renamed to
`NonEvaluateable::NonEvaluable`
- `ValArithmeticError::NonIdenticalVariants ` has been removed
# Objective
This PR implements `FromStr` for `Val`, so developers can parse values
like `10px` and `50%`
## Testing
Added tests for this. I think they cover pretty much everything, and
it's a fairly simple unit test.
## Limitations
Currently the following float values are not parsed:
- `inf`, `-inf`, `+infinity`, `NaN`
- `2.5E10`, `2.5e10`, `2.5E-10`
For my use case this is perfectly fine but other developers might want
to support these values
# Objective
Destructuring in const code blocks isn't allowed, thus using UIRect in
const code can be a hassle as it initialisation function aren't const.
This Pr makes them const.
## Solution
Removed all destructuring in the UIRect implementation
## Testing
- I've ran a few ui examples to check if i didn't make a mistake,
---
# Objective
- Remove `derive_more`'s error derivation and replace it with
`thiserror`
## Solution
- Added `derive_more`'s `error` feature to `deny.toml` to prevent it
sneaking back in.
- Reverted to `thiserror` error derivation
## Notes
Merge conflicts were too numerous to revert the individual changes, so
this reversion was done manually. Please scrutinise carefully during
review.
# Objective
Continue improving the user experience of our UI Node API in the
direction specified by [Bevy's Next Generation Scene / UI
System](https://github.com/bevyengine/bevy/discussions/14437)
## Solution
As specified in the document above, merge `Style` fields into `Node`,
and move "computed Node fields" into `ComputedNode` (I chose this name
over something like `ComputedNodeLayout` because it currently contains
more than just layout info. If we want to break this up / rename these
concepts, lets do that in a separate PR). `Style` has been removed.
This accomplishes a number of goals:
## Ergonomics wins
Specifying both `Node` and `Style` is now no longer required for
non-default styles
Before:
```rust
commands.spawn((
Node::default(),
Style {
width: Val::Px(100.),
..default()
},
));
```
After:
```rust
commands.spawn(Node {
width: Val::Px(100.),
..default()
});
```
## Conceptual clarity
`Style` was never a comprehensive "style sheet". It only defined "core"
style properties that all `Nodes` shared. Any "styled property" that
couldn't fit that mold had to be in a separate component. A "real" style
system would style properties _across_ components (`Node`, `Button`,
etc). We have plans to build a true style system (see the doc linked
above).
By moving the `Style` fields to `Node`, we fully embrace `Node` as the
driving concept and remove the "style system" confusion.
## Next Steps
* Consider identifying and splitting out "style properties that aren't
core to Node". This should not happen for Bevy 0.15.
---
## Migration Guide
Move any fields set on `Style` into `Node` and replace all `Style`
component usage with `Node`.
Before:
```rust
commands.spawn((
Node::default(),
Style {
width: Val::Px(100.),
..default()
},
));
```
After:
```rust
commands.spawn(Node {
width: Val::Px(100.),
..default()
});
```
For any usage of the "computed node properties" that used to live on
`Node`, use `ComputedNode` instead:
Before:
```rust
fn system(nodes: Query<&Node>) {
for node in &nodes {
let computed_size = node.size();
}
}
```
After:
```rust
fn system(computed_nodes: Query<&ComputedNode>) {
for computed_node in &computed_nodes {
let computed_size = computed_node.size();
}
}
```
# Objective
Another clippy-lint fix: the goal is so that `ci lints` actually
displays the problems that a contributor caused, and not a bunch of
existing stuff in the repo. (when run on nightly)
## Solution
This fixes all but the `clippy::needless_lifetimes` lint, which will
result in substantially more fixes and be in other PR(s). I also
explicitly allow `non_local_definitions` since it is [not working
correctly, but will be
fixed](https://github.com/rust-lang/rust/issues/131643).
A few things were manually fixed: for example, some places had an
explicitly defined `div_ceil` function that was used, which is no longer
needed since this function is stable on unsigned integers. Also, empty
lines in doc comments were handled individually.
## Testing
I ran `cargo clippy --workspace --all-targets --all-features --fix
--allow-staged` with the `clippy::needless_lifetimes` lint marked as
`allow` in `Cargo.toml` to avoid fixing that too. It now passes with all
but the listed lint.
# Objective
- Fixes#6370
- Closes#6581
## Solution
- Added the following lints to the workspace:
- `std_instead_of_core`
- `std_instead_of_alloc`
- `alloc_instead_of_core`
- Used `cargo +nightly fmt` with [item level use
formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Item%5C%3A)
to split all `use` statements into single items.
- Used `cargo clippy --workspace --all-targets --all-features --fix
--allow-dirty` to _attempt_ to resolve the new linting issues, and
intervened where the lint was unable to resolve the issue automatically
(usually due to needing an `extern crate alloc;` statement in a crate
root).
- Manually removed certain uses of `std` where negative feature gating
prevented `--all-features` from finding the offending uses.
- Used `cargo +nightly fmt` with [crate level use
formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Crate%5C%3A)
to re-merge all `use` statements matching Bevy's previous styling.
- Manually fixed cases where the `fmt` tool could not re-merge `use`
statements due to conditional compilation attributes.
## Testing
- Ran CI locally
## Migration Guide
The MSRV is now 1.81. Please update to this version or higher.
## Notes
- This is a _massive_ change to try and push through, which is why I've
outlined the semi-automatic steps I used to create this PR, in case this
fails and someone else tries again in the future.
- Making this change has no impact on user code, but does mean Bevy
contributors will be warned to use `core` and `alloc` instead of `std`
where possible.
- This lint is a critical first step towards investigating `no_std`
options for Bevy.
---------
Co-authored-by: François Mockers <francois.mockers@vleue.com>
# Objective
Originally proposed as part of #8973. Adds `with_` methods for each side
of `UiRect`
## Solution
Add `with_left`, `with_right`, `with_top`, `with_bottom` to `UiRect`.
# Objective
- Fixes#11119
## Solution
- Creation of the serialize feature to ui
---
## Changelog
### Changed
- Changed all the structs that implement Serialize and Deserialize to
only implement when feature is on
## Migration Guide
- If you want to use serialize and deserialize with types from bevy_ui,
you need to use the feature serialize in your TOML
```toml
[dependencies.bevy]
features = ["serialize"]
```
# Objective
- Revert #10296
## Solution
- Avoid implementing `Display` without a justification
- `Display` implementation is a guarantee without a direct use, takes
additional time to compile and require work to maintain
- `Debug`, `Reflect` or `Serialize` should cover all needs
# Objective
`Val`'s natural place is in the `geometry` module with `UiRect`, not in
`ui_node` with the components.
## Solution
Move `Val` into `geometry`.
# Objective
- Fixes#9533
## Solution
* Added `Val::ZERO` as a constant which is defined as `Val::Px(0.)`.
* Added manual `PartialEq` implementation for `Val` which allows any
zero value to equal any other zero value. E.g., `Val::Px(0.) ==
Val::Percent(0.)` etc. This is technically a breaking change, as
`Val::Px(0.) == Val::Percent(0.)` now equals `true` instead of `false`
(as an example)
* Replaced instances of `Val::Px(0.)`, `Val::Percent(0.)`, etc. with
`Val::ZERO`
* Fixed `bevy_ui::layout::convert::tests::test_convert_from` test to
account for Taffy not equating `Points(0.)` and `Percent(0.)`. These
tests now use `assert_eq!(...)` instead of `assert!(matches!(...))`
which gives easier to diagnose error messages.
# Objective
**This implementation is based on
https://github.com/bevyengine/rfcs/pull/59.**
---
Resolves#4597
Full details and motivation can be found in the RFC, but here's a brief
summary.
`FromReflect` is a very powerful and important trait within the
reflection API. It allows Dynamic types (e.g., `DynamicList`, etc.) to
be formed into Real ones (e.g., `Vec<i32>`, etc.).
This mainly comes into play concerning deserialization, where the
reflection deserializers both return a `Box<dyn Reflect>` that almost
always contain one of these Dynamic representations of a Real type. To
convert this to our Real type, we need to use `FromReflect`.
It also sneaks up in other ways. For example, it's a required bound for
`T` in `Vec<T>` so that `Vec<T>` as a whole can be made `FromReflect`.
It's also required by all fields of an enum as it's used as part of the
`Reflect::apply` implementation.
So in other words, much like `GetTypeRegistration` and `Typed`, it is
very much a core reflection trait.
The problem is that it is not currently treated like a core trait and is
not automatically derived alongside `Reflect`. This makes using it a bit
cumbersome and easy to forget.
## Solution
Automatically derive `FromReflect` when deriving `Reflect`.
Users can then choose to opt-out if needed using the
`#[reflect(from_reflect = false)]` attribute.
```rust
#[derive(Reflect)]
struct Foo;
#[derive(Reflect)]
#[reflect(from_reflect = false)]
struct Bar;
fn test<T: FromReflect>(value: T) {}
test(Foo); // <-- OK
test(Bar); // <-- Panic! Bar does not implement trait `FromReflect`
```
#### `ReflectFromReflect`
This PR also automatically adds the `ReflectFromReflect` (introduced in
#6245) registration to the derived `GetTypeRegistration` impl— if the
type hasn't opted out of `FromReflect` of course.
<details>
<summary><h4>Improved Deserialization</h4></summary>
> **Warning**
> This section includes changes that have since been descoped from this
PR. They will likely be implemented again in a followup PR. I am mainly
leaving these details in for archival purposes, as well as for reference
when implementing this logic again.
And since we can do all the above, we might as well improve
deserialization. We can now choose to deserialize into a Dynamic type or
automatically convert it using `FromReflect` under the hood.
`[Un]TypedReflectDeserializer::new` will now perform the conversion and
return the `Box`'d Real type.
`[Un]TypedReflectDeserializer::new_dynamic` will work like what we have
now and simply return the `Box`'d Dynamic type.
```rust
// Returns the Real type
let reflect_deserializer = UntypedReflectDeserializer::new(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
let output: SomeStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?;
// Returns the Dynamic type
let reflect_deserializer = UntypedReflectDeserializer::new_dynamic(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
let output: DynamicStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?;
```
</details>
---
## Changelog
* `FromReflect` is now automatically derived within the `Reflect` derive
macro
* This includes auto-registering `ReflectFromReflect` in the derived
`GetTypeRegistration` impl
* ~~Renamed `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` to
`TypedReflectDeserializer::new_dynamic` and
`UntypedReflectDeserializer::new_dynamic`, respectively~~ **Descoped**
* ~~Changed `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` to automatically convert the
deserialized output using `FromReflect`~~ **Descoped**
## Migration Guide
* `FromReflect` is now automatically derived within the `Reflect` derive
macro. Items with both derives will need to remove the `FromReflect`
one.
```rust
// OLD
#[derive(Reflect, FromReflect)]
struct Foo;
// NEW
#[derive(Reflect)]
struct Foo;
```
If using a manual implementation of `FromReflect` and the `Reflect`
derive, users will need to opt-out of the automatic implementation.
```rust
// OLD
#[derive(Reflect)]
struct Foo;
impl FromReflect for Foo {/* ... */}
// NEW
#[derive(Reflect)]
#[reflect(from_reflect = false)]
struct Foo;
impl FromReflect for Foo {/* ... */}
```
<details>
<summary><h4>Removed Migrations</h4></summary>
> **Warning**
> This section includes changes that have since been descoped from this
PR. They will likely be implemented again in a followup PR. I am mainly
leaving these details in for archival purposes, as well as for reference
when implementing this logic again.
* The reflect deserializers now perform a `FromReflect` conversion
internally. The expected output of `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` is no longer a Dynamic (e.g.,
`DynamicList`), but its Real counterpart (e.g., `Vec<i32>`).
```rust
let reflect_deserializer =
UntypedReflectDeserializer::new_dynamic(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
// OLD
let output: DynamicStruct = reflect_deserializer.deserialize(&mut
deserializer)?.take()?;
// NEW
let output: SomeStruct = reflect_deserializer.deserialize(&mut
deserializer)?.take()?;
```
Alternatively, if this behavior isn't desired, use the
`TypedReflectDeserializer::new_dynamic` and
`UntypedReflectDeserializer::new_dynamic` methods instead:
```rust
// OLD
let reflect_deserializer = UntypedReflectDeserializer::new(®istry);
// NEW
let reflect_deserializer =
UntypedReflectDeserializer::new_dynamic(®istry);
```
</details>
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Make the UI code more concise.
## Solution
Add two utility methods to make manipulating `UiRect` from code more
concise:
- `UiRect::px()` create a new `UiRect` like the `new()` function, but
with values in logical pixels directly.
- `UiRect::percent()` is similar, with values as percentages.
This saves a lot of typing and makes UI code more compact while
retaining readability.
---
## Changelog
### Added
Added two new constructors `UiRect::px()` and `UiRect::percent()` to
create a new `UiRect` from values directly specified in logical pixels
and percentages, respectively. The argument order is the same as
`UiRect::new()`, but avoids having to repeat `Val::Px` and
`Val::Percent`, respectively.
# Objective
- Simplify API and make authoring styles easier
See:
https://github.com/bevyengine/bevy/issues/8540#issuecomment-1536177102
## Solution
- The `size`, `min_size`, `max_size`, and `gap` properties have been
replaced by `width`, `height`, `min_width`, `min_height`, `max_width`,
`max_height`, `row_gap`, and `column_gap` properties
---
## Changelog
- Flattened `Style` properties that have a `Size` value directly into
`Style`
## Migration Guide
- The `size`, `min_size`, `max_size`, and `gap` properties have been
replaced by the `width`, `height`, `min_width`, `min_height`,
`max_width`, `max_height`, `row_gap`, and `column_gap` properties. Use
the new properties instead.
---------
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
# Objective
A lot of items in `bevy_ui` could be `FromReflect` but aren't. This
prevents users and library authors from being able to convert from a
`dyn Reflect` to one of these items.
## Solution
Derive `FromReflect` where possible. Also register the
`ReflectFromReflect` type data.
# Objective
We don't have a constructor function for `UiRect` that sets uniform
horizontal and vertical values, even though it is a common pattern.
## Solution
Add a constructor function to `UiRect` called `axes`, that sets both
`left` and `right` to the same given horizontal value,
and sets both `top` and `bottom` to same given vertical value.
## Changelog
* Added a constructor function `axes` to `UiRect`.
# Objective
Add doc tests for the `Size` constructor functions.
Also changed the function descriptions so they explicitly state the values that elided values are given.
## Changelog
* Added doc tests for the `Size` constructor functions.
# Objective
`Size::width` sets the `height` field to `Val::DEFAULT` which is `Val::Undefined`, but the default for `Size` `height` is `Val::Auto`.
`Size::height` has the same problem, but with the `width` field.
The UI examples specify numeric values in many places where they could either be elided or replaced by composition of the Flex enum properties.
related: https://github.com/bevyengine/bevy/pull/7468
fixes: https://github.com/bevyengine/bevy/issues/6498
## Solution
Change `Size::width` so it sets `height` to `Val::AUTO` and change `Size::height` so it sets `width` to `Val::AUTO`.
Added some tests so this doesn't happen again.
## Changelog
Changed `Size::width` so it sets the `height` to `Val::AUTO`.
Changed `Size::height` so it sets the `width` to `Val::AUTO`.
Added tests to `geometry.rs` for `Size` and `UiRect` to ensure correct behaviour.
Simplified the UI examples. Replaced numeric values with the Flex property enums or elided them where possible, and removed the remaining use of auto margins.
## Migration Guide
The `Size::width` constructor function now sets the `height` to `Val::Auto` instead of `Val::Undefined`.
The `Size::height` constructor function now sets the `width` to `Val::Auto` instead of `Val::Undefined`.
# Objective
In CSS Flexbox width and height are auto by default, whereas in Bevy their default is `Size::Undefined`.
This means that, unlike in CSS, if you elide a height or width value for a node it will be given zero length (unless it has an explicitly sized child node). This has misled users into falsely assuming that they have to explicitly set a value for both height and width all the time.
relevant issue: #7120
## Solution
Change the `Size` `width` and `height` default values to `Val::Auto`
## Changelog
* Changed the `Size` `width` and `height` default values to `Val::Auto`
## Migration Guide
The default values for `Size` `width` and `height` have been changed from `Val::Undefined` to `Val::Auto`.
It's unlikely to cause any issues with existing code.
## Objective
A common easy to miss mistake is to write something like:
``` rust
Size::new(Val::Percent(100.), Val::Px(100.));
```
`UiRect` has the `left`, `right`, `all`, `vertical`, etc constructor functions, `Size` is used a lot more frequently but lacks anything similar.
## Solution
Implement `all`, `width` and `height` functions for `Size`.
## Changelog
* Added `all`, `width` and `height` functions to `Size`.
# Objective
- Fixes#5529
## Solution
- Add assosciated constants named DEFAULT to as many types as possible
- Add const to as many methods in bevy_ui as possible
I have not applied the same treatment to the bundles in bevy_ui as it would require going into other bevy crates to implement const defaults for structs in bevy_text or relies on UiImage which calls HandleUntyped.typed() which isn't const safe.
Alternatively the defaults could relatively easily be turned into a macro to regain some of the readability and conciseness at the cost of explicitness.
Such a macro that partially implements this exists as a crate here: [const-default](https://docs.rs/const-default/latest/const_default/derive.ConstDefault.html) but does not support enums.
Let me know if there's anything I've missed or if I should push further into other crates.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Fixes#6594
## Solution
- `New` function for `Size` is now a `const` function :)
## Changelog
- `New` function for `Size` is now a `const` function
## Migration Guide
- Nothing has been changed
# Objective
Adds a better interface for performing mathematical operations with UI unit `Val`. Fixes#6080.
## Solution
- Added `try_add` and `try_sub` methods to Val.
- Removed the `Add` and `AddAssign` impls for `Val` that introduced unintuitive and bug-prone behaviour.
- As a consequence of the prior, ~~changed the `Add` and `Sub` impls for the `Size` struct to take a `(Val, Val)` instead of `Vec2`~~ deleted the `Add` and `Sub` impls for the `Size` struct
- Added a `From<(Val, Val)>` impl for the `Size` struct
- Added `evaluate(size: f32)` method that converts from `Val::Percent` to `Val::Px`.
- Added `try_add_with_size` and `try_sub_with_size` methods to `Val`, which evaluate `Val::Percent` values into `Val::Px` values before adding.
---
## Migration Guide
Instead of using the + and - operators, perform calculations on `Val`s using the new `try_add` and `try_sub` methods. Multiplication and division remained unchanged. Also, when adding or subtracting from `Size`, ~~use a `Val` tuple instead of `Vec2`~~ perform the addition on `width` and `height` separately.
Co-authored-by: Dawid Piotrowski <41804418+Pietrek14@users.noreply.github.com>
# Objective
Often one wants to create a `UiRect` with a value only specifying a single field. These ways are already available, but not the most ergonomic:
```rust
UiRect::new(Val::Undefined, Val::Undefined, Val::Percent(25.0), Val::Undefined)
```
```rust
UiRect {
top: Val::Percent(25.0),
..default()
}
```
## Solution
Introduce 6 new constructors:
- `horizontal`
- `vertical`
- `left`
- `right`
- `top`
- `bottom`
So the above code can be written instead as:
```rust
UiRect::top(Val::Percent(25.0))
```
This solution is similar to the style fields `margin-left`, `padding-top`, etc. that you would see in CSS, from which bevy's UI has other inspiration. Therefore, it should still feel intuitive to users coming from CSS.
---
## Changelog
### Added
- Additional constructors for `UiRect` to specify values for specific fields
# Objective
Very small convenience constructors added to `Size`.
Does not change current examples too much but I'm working on a rather complex UI use-case where this cuts down on some extra typing :)
# Objective
- Migrate changes from #3503.
## Solution
- Change `Size<T>` and `UiRect<T>` to `Size` and `UiRect` using `Val`.
- Implement `Sub`, `SubAssign`, `Mul`, `MulAssign`, `Div` and `DivAssign` for `Val`.
- Update tests for `Size`.
---
## Changelog
### Changed
- The generic `T` of `Size` and `UiRect` got removed and instead they both now always use `Val`.
## Migration Guide
- The generic `T` of `Size` and `UiRect` got removed and instead they both now always use `Val`. If you used a `Size<f32>` consider replacing it with a `Vec2` which is way more powerful.
Co-authored-by: KDecay <KDecayMusic@protonmail.com>
# Objective
- Migrate changes from #3503.
## Solution
- Document `Size` and `UiRect`.
- I also removed the type alias from the `size_ops` test since it's unnecessary.
## Follow Up
After this change is merged I'd follow up with removing the generics from `Size` and `UiRect` since `Val` should be extensible enough. This was also discussed and decided on in #3503. let me know if this is not needed or wanted anymore!
# Objective
- Closes#335.
- Related #4285.
- Part of the splitting process of #3503.
## Solution
- Move `Rect` to `bevy_ui` and rename it to `UiRect`.
## Reasons
- `Rect` is only used in `bevy_ui` and therefore calling it `UiRect` makes the intent clearer.
- We have two types that are called `Rect` currently and it's missleading (see `bevy_sprite::Rect` and #335).
- Discussion in #3503.
## Changelog
### Changed
- The `Rect` type got moved from `bevy_math` to `bevy_ui` and renamed to `UiRect`.
## Migration Guide
- The `Rect` type got renamed to `UiRect`. To migrate you just have to change every occurrence of `Rect` to `UiRect`.
Co-authored-by: KDecay <KDecayMusic@protonmail.com>
# Objective
- Related #4276.
- Part of the splitting process of #3503.
## Solution
- Move `Size` to `bevy_ui`.
## Reasons
- `Size` is only needed in `bevy_ui` (because it needs to use `Val` instead of `f32`), but it's also used as a worse `Vec2` replacement in other areas.
- `Vec2` is more powerful than `Size` so it should be used whenever possible.
- Discussion in #3503.
## Changelog
### Changed
- The `Size` type got moved from `bevy_math` to `bevy_ui`.
## Migration Guide
- The `Size` type got moved from `bevy::math` to `bevy::ui`. To migrate you just have to import `bevy::ui::Size` instead of `bevy::math::Math` or use the `bevy::prelude` instead.
Co-authored-by: KDecay <KDecayMusic@protonmail.com>
