# Objective
`RemoveChildren` could remove the `Parent` component from children belonging to a different parent, which breaks the hierarchy.
This change looks a little funny because I'm reusing the events to avoid needing to clone the parent's `Children`.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
- Taking the API improvement out of #5431
- `iter_instance_entities` used to return an option of iterator, now it just returns an iterator
---
## Changelog
- If you use `SceneSpawner::iter_instance_entities`, it no longer returns an `Option`. The iterator will be empty if the return value used to be `None`
# Objective
- Adding Debug implementations for App, Stage, Schedule, Query, QueryState.
- Fixes#1130.
## Solution
- Implemented std::fmt::Debug for a number of structures.
---
## Changelog
Also added Debug implementations for ParallelSystemExecutor, SingleThreadedExecutor, various RunCriteria structures, SystemContainer, and SystemDescriptor.
Opinions are sure to differ as to what information to provide in a Debug implementation. Best guess was taken for this initial version for these structures.
Co-authored-by: targrub <62773321+targrub@users.noreply.github.com>
See commit message.
I noticed I couldn't use `globals.time` when using `Material2d`.
I copied the solution from 8073362039 , and now `Material2d` works for me.
Perhaps some of these struct definitions could be shared in the future, but for now I've just copy pasted it (it looked like the `View` struct was done that way).
Ping @IceSentry , I saw a comment on the linked commit that you intended to do this work at some point in the future.
# Objective
- It's possible to create a mesh without positions or normals, but currently bevy forces these attributes to be present on any mesh.
## Solution
- Don't assume these attributes are present and add a shader defs for each attributes
- I updated 2d and 3d meshes to use the same logic.
---
## Changelog
- Meshes don't require any attributes
# Notes
I didn't update the pbr.wgsl shader because I'm not sure how to handle it. It doesn't really make sense to use it without positions or normals.
# Objective
- `process_touch_event` in `bevy_input` don't update position info. `TouchPhase::Ended` and `TouchPhase::Cancelled` should use the position info from `pressed`. Otherwise, it'll not update. The position info is updated from `TouchPhase::Moved`.
## Solution
- Use updated touch info.
---
## Changelog
> This section is optional. If this was a trivial fix, or has no externally-visible impact, feel free to skip this section.
- Fixed: bevy_input, fix process touch event, update touch info
# Objective
When designing an API, you may wish to provide access only to a specific field of a component or resource. The current options for doing this in safe code are
* `*Mut::into_inner`, which flags a change no matter what.
* `*Mut::bypass_change_detection`, which misses all changes.
## Solution
Add the method `map_unchanged`.
### Example
```rust
// When run, zeroes the translation of every entity.
fn reset_all(mut transforms: Query<&mut Transform>) {
for transform in &mut transforms {
// We pinky promise not to modify `t` within the closure.
let translation = transform.map_unchanged(|t| &mut t.translation);
// Only reset the translation if it isn't already zero.
translation.set_if_not_equal(Vec2::ZERO);
}
}
```
---
## Changelog
+ Added the method `map_unchanged` to types `Mut<T>`, `ResMut<T>`, and `NonSendMut<T>`.
This is a holdover from back when `Transform` was backed by a private `Mat4` two years ago.
Not particularly useful anymore :)
## Migration Guide
`Transform::apply_non_uniform_scale` has been removed.
It can be replaced with the following snippet:
```rust
transform.scale *= scale_factor;
```
Co-authored-by: devil-ira <justthecooldude@gmail.com>
The docs ended up quite verbose :v
Also added a missing `#[inline]` to `GlobalTransform::mul_transform`.
I'd say this resolves#5500
# Migration Guide
`Transform::mul_vec3` has been renamed to `transform_point`.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
Make `GlobalTransform` constructible from scripts, in the same vein as #6187.
## Solution
- Use the derive macro to reflect default
---
## Changelog
> This section is optional. If this was a trivial fix, or has no externally-visible impact, you can delete this section.
- `GlobalTransform` now reflects the `Default` trait.
…
# Objective
- Fixes Camera not being serializable due to missing registrations in core functionality.
- Fixes#6169
## Solution
- Updated Bevy_Render CameraPlugin with registrations for Option<Viewport> and then Bevy_Core CorePlugin with registrations for ReflectSerialize and ReflectDeserialize for type data Range<f32> respectively according to the solution in #6169
Co-authored-by: Noah <noahshomette@gmail.com>
# Background
Incremental implementation of #4299. The code is heavily borrowed from that PR.
# Objective
The execution order ambiguity checker often emits false positives, since bevy is not aware of invariants upheld by the user.
## Solution
Title
---
## Changelog
+ Added methods `SystemDescriptor::ignore_all_ambiguities` and `::ambiguous_with`. These allow you to silence warnings for specific system-order ambiguities.
## Migration Guide
***Note for maintainers**: This should replace the migration guide for #5916*
Ambiguity sets have been replaced with a simpler API.
```rust
// These systems technically conflict, but we don't care which order they run in.
fn jump_on_click(mouse: Res<Input<MouseButton>>, mut transforms: Query<&mut Transform>) { ... }
fn jump_on_spacebar(keys: Res<Input<KeyCode>>, mut transforms: Query<&mut Transform>) { ... }
//
// Before
#[derive(AmbiguitySetLabel)]
struct JumpSystems;
app
.add_system(jump_on_click.in_ambiguity_set(JumpSystems))
.add_system(jump_on_spacebar.in_ambiguity_set(JumpSystems));
//
// After
app
.add_system(jump_on_click.ambiguous_with(jump_on_spacebar))
.add_system(jump_on_spacebar);
```
# Objective
There is no Srgb support on some GPU and display protocols with `winit` (for example, Nvidia's GPUs with Wayland). Thus `TextureFormat::bevy_default()` which returns `Rgba8UnormSrgb` or `Bgra8UnormSrgb` will cause panics on such platforms. This patch will resolve this problem. Fix https://github.com/bevyengine/bevy/issues/3897.
## Solution
Make `initialize_renderer` expose `wgpu::Adapter` and `first_available_texture_format`, use the `first_available_texture_format` by default.
## Changelog
* Fixed https://github.com/bevyengine/bevy/issues/3897.
# Objective
Closes#6202.
The default background color for `NodeBundle` is currently white.
However, it's very rare that you actually want a white background color.
Instead, you often want a background color specific to the style of your game or a transparent background (e.g. for UI layout nodes).
## Solution
`Default` is not derived for `NodeBundle` anymore, but explicitly specified.
The default background color is now transparent (`Color::NONE.into()`) as this is the most common use-case, is familiar from the web and makes specifying a layout for your UI less tedious.
---
## Changelog
- Changed the default `NodeBundle.background_color` to be transparent (`Color::NONE.into()`).
## Migration Guide
If you want a `NodeBundle` with a white background color, you must explicitly specify it:
Before:
```rust
let node = NodeBundle {
..default()
}
```
After:
```rust
let node = NodeBundle {
background_color: Color::WHITE.into(),
..default()
}
```
# Objective
Allow `Mesh2d` shaders to work with meshes that have vertex tangents
## Solution
Correctly pass `mesh.model` into `mesh2d_tangent_local_to_world`
# Objective
Fixes#6010
## Solution
As discussed in #6010, this makes it so the `Children` component is removed from the entity whenever all of its children are removed. The behavior is now consistent between all of the commands that may remove children from a parent, and this is tested via two new test functions (one for world functions and one for commands).
Documentation was also added to `insert_children`, `push_children`, `add_child` and `remove_children` commands to make this behavior clearer for users.
## Changelog
- Fixed `Children` component not getting removed from entity when all its children are moved to a new parent.
## Migration Guide
- Queries with `Changed<Children>` will no longer match entities that had all of their children removed using `remove_children`.
- `RemovedComponents<Children>` will now contain entities that had all of their children remove using `remove_children`.
# Objective
- Reflecting `Default` is required for scripts to create `Reflect` types at runtime with no static type information.
- Reflecting `Default` on `Handle<T>` and `ComputedVisibility` should allow scripts from `bevy_mod_js_scripting` to actually spawn sprites from scratch, without needing any hand-holding from the host-game.
## Solution
- Derive `ReflectDefault` for `Handle<T>` and `ComputedVisiblity`.
---
## Changelog
> This section is optional. If this was a trivial fix, or has no externally-visible impact, you can delete this section.
- The `Default` trait is now reflected for `Handle<T>` and `ComputedVisibility`
# Objective
- Field `id` of `Handle<T>` is public: https://docs.rs/bevy/latest/bevy/asset/struct.Handle.html#structfield.id
- Changing the value of this field doesn't make sense as it could mean changing the previous handle without dropping it, breaking asset cleanup detection for the old handle and the new one
## Solution
- Make the field private, and add a public getter
Opened after discussion in #6171. Pinging @zicklag
---
## Migration Guide
- If you were accessing the value `handle.id`, you can now do so with `handle.id()`
# Objective
Add a method for getting a world space ray from a viewport position.
Opted to add a `Ray` type to `bevy_math` instead of returning a tuple of `Vec3`'s as this is clearer and easier to document
The docs on `viewport_to_world` are okay, but I'm not super happy with them.
## Changelog
* Add `Camera::viewport_to_world`
* Add `Camera::ndc_to_world`
* Add `Ray` to `bevy_math`
* Some doc tweaks
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
- Fix#5285
## Solution
- Put the panicking system in a single threaded stage during the test
- This way only the main thread will panic, which is handled by `cargo test`
# Objective
- Fixes contradictory docs in Window::PresentMode partaining to PresentMode fallback behavior. Fix based on commit history showing the most recent update didn't remove old references to the gracefal fallback for Immediate and Mailbox.
- Fixes#5831
## Solution
- Updated the docs for Window::PresentMode itself and for each individual enum variant to clarify which will fallback and which will panic.
Co-authored-by: Noah <noahshomette@gmail.com>
# Objective
fix error with pbr shader's spotlight direction calculation when direction.y ~= 0
## Solution
in pbr_lighting.wgsl, clamp `1-x^2-z^2` to `>= 0` so that we can safely `sqrt` it
# Objective
The `Wireframe` type implements `Reflect`, but is never registered, making its reflection inaccessible.
## Solution
Call `App::register_type::<Wireframe>()` in the `Plugin::build` implementation of `WireframePlugin`.
---
## Changelog
Fixed `Wireframe` type reflection not getting registered.
# Objective
Add more documentation on `StandardMaterial` and improve
consistency on existing doc.
Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
# Objective
Relaxes the trait bound for `World::resource_scope` to allow non-send resources. Fixes#6037.
## Solution
No big changes in code had to be made. Added a check so that the non-send resources won't be accessed from a different thread.
---
## Changelog
- `World::resource_scope` accepts non-send resources now
- `World::resource_scope` verifies non-send access if the resource is non-send
- Two new tests are added, one for valid use of `World::resource_scope` with a non-send resource, and one for invalid use (calling it from a different thread, resulting in panic)
Co-authored-by: Dawid Piotrowski <41804418+Pietrek14@users.noreply.github.com>
# Objective
As explained by #5960, `Commands::get_or_spawn` may return a dangling `EntityCommands` that references a non-existing entities. As explained in [this comment], it may be undesirable to make the method return an `Option`.
- Addresses #5960
- Alternative to #5961
## Solution
This PR adds a doc comment to the method to inform the user that the returned `EntityCommands` is not guaranteed to be valid. It also adds panic doc comments on appropriate `EntityCommands` methods.
[this comment]: https://github.com/bevyengine/bevy/pull/5961#issuecomment-1259870849
# Objective
- Alpha mask was previously ignored when using an unlit material.
- Fixes https://github.com/bevyengine/bevy/issues/4479
## Solution
- Extract the alpha discard to a separate function and use it when unlit is true
## Notes
I tried calling `alpha_discard()` before the `if` in pbr.wgsl, but I had errors related to having a `discard` at the beginning before doing the texture sampling. I'm not sure if there's a way to fix that instead of having the function being called in 2 places.
# Objective
- Currently, errors aren't logged as soon as they are found, they are logged only on the next frame. This means your shader could have an unreported error that could have been reported on the first frame.
## Solution
- Log the error as soon as they are found, don't wait until next frame
## Notes
I discovered this issue because I was simply unwrapping the `Result` from `PipelinCache::get_render_pipeline()` which caused it to fail without any explanations. Admittedly, this was a bit of a user error, I shouldn't have unwrapped that, but it seems a bit strange to wait until the next time the pipeline is processed to log the error instead of just logging it as soon as possible since we already have all the info necessary.
# Objective
- Add ability to create nested spawns. This is needed for stageless. The current executor spawns tasks for each system early and runs the system by communicating through a channel. In stageless we want to spawn the task late, so that archetypes can be updated right before the task is run. The executor is run on a separate task, so this enables the scope to be passed to the spawned executor.
- Fixes#4301
## Solution
- Instantiate a single threaded executor on the scope and use that instead of the LocalExecutor. This allows the scope to be Send, but still able to spawn tasks onto the main thread the scope is run on. This works because while systems can access nonsend data. The systems themselves are Send. Because of this change we lose the ability to spawn nonsend tasks on the scope, but I don't think this is being used anywhere. Users would still be able to use spawn_local on TaskPools.
- Steals the lifetime tricks the `std:🧵:scope` uses to allow nested spawns, but disallow scope to be passed to tasks or threads not associated with the scope.
- Change the storage for the tasks to a `ConcurrentQueue`. This is to allow a &Scope to be passed for spawning instead of a &mut Scope. `ConcurrentQueue` was chosen because it was already in our dependency tree because `async_executor` depends on it.
- removed the optimizations for 0 and 1 spawned tasks. It did improve those cases, but made the cases of more than 1 task slower.
---
## Changelog
Add ability to nest spawns
```rust
fn main() {
let pool = TaskPool::new();
pool.scope(|scope| {
scope.spawn(async move {
// calling scope.spawn from an spawn task was not possible before
scope.spawn(async move {
// do something
});
});
})
}
```
## Migration Guide
If you were using explicit lifetimes and Passing Scope you'll need to specify two lifetimes now.
```rust
fn scoped_function<'scope>(scope: &mut Scope<'scope, ()>) {}
// should become
fn scoped_function<'scope>(scope: &Scope<'_, 'scope, ()>) {}
```
`scope.spawn_local` changed to `scope.spawn_on_scope` this should cover cases where you needed to run tasks on the local thread, but does not cover spawning Nonsend Futures.
## TODO
* [x] think real hard about all the lifetimes
* [x] add doc about what 'env and 'scope mean.
* [x] manually check that the single threaded task pool still works
* [x] Get updated perf numbers
* [x] check and make sure all the transmutes are necessary
* [x] move commented out test into a compile fail test
* [x] look through the tests for scope on std and see if I should add any more tests
Co-authored-by: Michael Hsu <myhsu@benjaminelectric.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Make `Res` cloneable
## Solution
Add an associated fn `clone(self: &Self) -. Self` instead of `Copy + Clone` trait impls to avoid `res.clone()` failing to clone out the underlying `T`
# 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
Currently, arrays cannot indexed using the reflection path API.
This change makes them behave like lists so `x.get_path("list[0]")` will behave the same way, whether x.list is a "List" (e.g. a Vec) or an array.
## Solution
When syntax is encounterd `[ <idx> ]` we check if the referenced type is either a `ReflectRef::List` or `ReflectRef::Array` (or `ReflectMut` for the mutable case). Since both provide the identical API for accessing entries, we do the same for both, although it requires code duplication as far as I can tell.
This was born from working on #5764, but since this seems to be an easier fix (and I am not sure if I can actually solve #5812) I figured it might be worth to split this out.
# Objective
Simple docs/comments only PR that just fixes some outdated file references left over from the render rewrite.
## Solution
- Change the references to point to the correct files
# Objective
The [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) involves allowing exclusive systems to be referenced and ordered relative to parallel systems. We've agreed that unifying systems under `System` is the right move.
This is an alternative to #4166 (see rationale in the comments I left there). Note that this builds on the learnings established there (and borrows some patterns).
## Solution
This unifies parallel and exclusive systems under the shared `System` trait, removing the old `ExclusiveSystem` trait / impls. This is accomplished by adding a new `ExclusiveFunctionSystem` impl similar to `FunctionSystem`. It is backed by `ExclusiveSystemParam`, which is similar to `SystemParam`. There is a new flattened out SystemContainer api (which cuts out a lot of trait and type complexity).
This means you can remove all cases of `exclusive_system()`:
```rust
// before
commands.add_system(some_system.exclusive_system());
// after
commands.add_system(some_system);
```
I've also implemented `ExclusiveSystemParam` for `&mut QueryState` and `&mut SystemState`, which makes this possible in exclusive systems:
```rust
fn some_exclusive_system(
world: &mut World,
transforms: &mut QueryState<&Transform>,
state: &mut SystemState<(Res<Time>, Query<&Player>)>,
) {
for transform in transforms.iter(world) {
println!("{transform:?}");
}
let (time, players) = state.get(world);
for player in players.iter() {
println!("{player:?}");
}
}
```
Note that "exclusive function systems" assume `&mut World` is present (and the first param). I think this is a fair assumption, given that the presence of `&mut World` is what defines the need for an exclusive system.
I added some targeted SystemParam `static` constraints, which removed the need for this:
``` rust
fn some_exclusive_system(state: &mut SystemState<(Res<'static, Time>, Query<&'static Player>)>) {}
```
## Related
- #2923
- #3001
- #3946
## Changelog
- `ExclusiveSystem` trait (and implementations) has been removed in favor of sharing the `System` trait.
- `ExclusiveFunctionSystem` and `ExclusiveSystemParam` were added, enabling flexible exclusive function systems
- `&mut SystemState` and `&mut QueryState` now implement `ExclusiveSystemParam`
- Exclusive and parallel System configuration is now done via a unified `SystemDescriptor`, `IntoSystemDescriptor`, and `SystemContainer` api.
## Migration Guide
Calling `.exclusive_system()` is no longer required (or supported) for converting exclusive system functions to exclusive systems:
```rust
// Old (0.8)
app.add_system(some_exclusive_system.exclusive_system());
// New (0.9)
app.add_system(some_exclusive_system);
```
Converting "normal" parallel systems to exclusive systems is done by calling the exclusive ordering apis:
```rust
// Old (0.8)
app.add_system(some_system.exclusive_system().at_end());
// New (0.9)
app.add_system(some_system.at_end());
```
Query state in exclusive systems can now be cached via ExclusiveSystemParams, which should be preferred for clarity and performance reasons:
```rust
// Old (0.8)
fn some_system(world: &mut World) {
let mut transforms = world.query::<&Transform>();
for transform in transforms.iter(world) {
}
}
// New (0.9)
fn some_system(world: &mut World, transforms: &mut QueryState<&Transform>) {
for transform in transforms.iter(world) {
}
}
```
# Objective
I was working with the TextBundle component bundle because I wanted to change the position of the text that the bundle was holding. I used the transform field on the TextBundle at first because that is normally what controls the position of sprites in Bevy and that's what I was used to working with.
But the actual way to change the position of text inside of a TextBundle is to use the Style's position field, not the TextBundle's transform field.
Anecdotally, it was mentioned on the discord that other users have had this issue too.
## Solution
I added a small doc comment to the TextBundle's transform telling users not to use it to set the position of text. And since this issue applies to the other UI bundles, I added comments there as well!
# Objective
Fixes#6078. The `UiColor` component is unhelpfully named: it is unclear, ambiguous with border color and
## Solution
Rename the `UiColor` component (and associated fields) to `BackgroundColor` / `background_colorl`.
## Migration Guide
`UiColor` has been renamed to `BackgroundColor`. This change affects `NodeBundle`, `ButtonBundle` and `ImageBundle`. In addition, the corresponding field on `ExtractedUiNode` has been renamed to `background_color` for consistency.
This is an adoption of #3775
This merges `TextureAtlas` `from_grid_with_padding` into `from_grid` , adding optional padding and optional offset.
Since the orignal PR, the offset had already been added to from_grid_with_padding through #4836
## Changelog
- Added `padding` and `offset` arguments to `TextureAtlas::from_grid`
- Removed `TextureAtlas::from_grid_with_padding`
## Migration Guide
`TextureAtlas::from_grid_with_padding` was merged into `from_grid` which takes two additional parameters for padding and an offset.
```
// 0.8
TextureAtlas::from_grid(texture_handle, Vec2::new(24.0, 24.0), 7, 1);
// 0.9
TextureAtlas::from_grid(texture_handle, Vec2::new(24.0, 24.0), 7, 1, None, None)
// 0.8
TextureAtlas::from_grid_with_padding(texture_handle, Vec2::new(24.0, 24.0), 7, 1, Vec2::new(4.0, 4.0));
// 0.9
TextureAtlas::from_grid(texture_handle, Vec2::new(24.0, 24.0), 7, 1, Some(Vec2::new(4.0, 4.0)), None)
```
Co-authored-by: olefish <88390729+oledfish@users.noreply.github.com>
# Objective
- Sometimes, like when using shaders, you can only use a time value in `f32`. Unfortunately this suffers from floating precision issues pretty quickly. The standard approach to this problem is to wrap the time after a given period
- This is necessary for https://github.com/bevyengine/bevy/pull/5409
## Solution
- Add a `seconds_since_last_wrapping_period` method on `Time` that returns a `f32` that is the `seconds_since_startup` modulo the `max_wrapping_period`
---
## Changelog
Added `seconds_since_last_wrapping_period` to `Time`
## Additional info
I'm very opened to hearing better names. I don't really like the current naming, I just went with something descriptive.
Co-authored-by: Charles <IceSentry@users.noreply.github.com>
# Objective
Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands).
## Solution
All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input:
```rust
// before:
commands
.spawn()
.insert((A, B, C));
world
.spawn()
.insert((A, B, C);
// after
commands.spawn((A, B, C));
world.spawn((A, B, C));
```
All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api.
By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`).
This improves spawn performance by over 10%:
![image](https://user-images.githubusercontent.com/2694663/191627587-4ab2f949-4ccd-4231-80eb-80dd4d9ad6b9.png)
To take this measurement, I added a new `world_spawn` benchmark.
Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main.
**Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).**
---
## Changelog
- All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input
- All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api
- World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior.
## Migration Guide
```rust
// Old (0.8):
commands
.spawn()
.insert_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));
// Old (0.8):
commands.spawn_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));
// Old (0.8):
let entity = commands.spawn().id();
// New (0.9)
let entity = commands.spawn_empty().id();
// Old (0.8)
let entity = world.spawn().id();
// New (0.9)
let entity = world.spawn_empty();
```