# Objective
In the Render World, there are a number of collections that are derived
from Main World entities and are used to drive rendering. The most
notable are:
- `VisibleEntities`, which is generated in the `check_visibility` system
and contains visible entities for a view.
- `ExtractedInstances`, which maps entity ids to asset ids.
In the old model, these collections were trivially kept in sync -- any
extracted phase item could look itself up because the render entity id
was guaranteed to always match the corresponding main world id.
After #15320, this became much more complicated, and was leading to a
number of subtle bugs in the Render World. The main rendering systems,
i.e. `queue_material_meshes` and `queue_material2d_meshes`, follow a
similar pattern:
```rust
for visible_entity in visible_entities.iter::<With<Mesh2d>>() {
let Some(mesh_instance) = render_mesh_instances.get_mut(visible_entity) else {
continue;
};
// Look some more stuff up and specialize the pipeline...
let bin_key = Opaque2dBinKey {
pipeline: pipeline_id,
draw_function: draw_opaque_2d,
asset_id: mesh_instance.mesh_asset_id.into(),
material_bind_group_id: material_2d.get_bind_group_id().0,
};
opaque_phase.add(
bin_key,
*visible_entity,
BinnedRenderPhaseType::mesh(mesh_instance.automatic_batching),
);
}
```
In this case, `visible_entities` and `render_mesh_instances` are both
collections that are created and keyed by Main World entity ids, and so
this lookup happens to work by coincidence. However, there is a major
unintentional bug here: namely, because `visible_entities` is a
collection of Main World ids, the phase item being queued is created
with a Main World id rather than its correct Render World id.
This happens to not break mesh rendering because the render commands
used for drawing meshes do not access the `ItemQuery` parameter, but
demonstrates the confusion that is now possible: our UI phase items are
correctly being queued with Render World ids while our meshes aren't.
Additionally, this makes it very easy and error prone to use the wrong
entity id to look up things like assets. For example, if instead we
ignored visibility checks and queued our meshes via a query, we'd have
to be extra careful to use `&MainEntity` instead of the natural
`Entity`.
## Solution
Make all collections that are derived from Main World data use
`MainEntity` as their key, to ensure type safety and avoid accidentally
looking up data with the wrong entity id:
```rust
pub type MainEntityHashMap<V> = hashbrown::HashMap<MainEntity, V, EntityHash>;
```
Additionally, we make all `PhaseItem` be able to provide both their Main
and Render World ids, to allow render phase implementors maximum
flexibility as to what id should be used to look up data.
You can think of this like tracking at the type level whether something
in the Render World should use it's "primary key", i.e. entity id, or
needs to use a foreign key, i.e. `MainEntity`.
## Testing
##### TODO:
This will require extensive testing to make sure things didn't break!
Additionally, some extraction logic has become more complicated and
needs to be checked for regressions.
## Migration Guide
With the advent of the retained render world, collections that contain
references to `Entity` that are extracted into the render world have
been changed to contain `MainEntity` in order to prevent errors where a
render world entity id is used to look up an item by accident. Custom
rendering code may need to be changed to query for `&MainEntity` in
order to look up the correct item from such a collection. Additionally,
users who implement their own extraction logic for collections of main
world entity should strongly consider extracting into a different
collection that uses `MainEntity` as a key.
Additionally, render phases now require specifying both the `Entity` and
`MainEntity` for a given `PhaseItem`. Custom render phases should ensure
`MainEntity` is available when queuing a phase item.
# Objective
Fixes#15828
## Solution
Ran the example to generate `load_scene_example-new.scn.ron` and
replaced `load_scene_example.scn.ron` with the contents.
## Testing
`cargo run --example scene`
# Objective
Fixes#15824
## Solution
Looks like this was just a goof in migrating the example itself.
Added back in the rotation component of the transform that got dropped.
## Testing
`cargo run --example auto_exposure`
# Objective
I tried to improve gitignore. I am not a programming expert yet, so I
don't know all the junk files. If someone provides me with a list of
other files, can you point me to it below? I also tried to sort them
logically, hope it works.
> This is also my first PR in the history of this engine. and I'm very
happy 😄
# Objective
- Closes#15716
- Closes#15718
## Solution
- Replace `Handle<MeshletMesh>` with a new `MeshletMesh3d` component
- As expected there were some random things that needed fixing:
- A couple tests were storing handles just to prevent them from being
dropped I believe, which seems to have been unnecessary in some.
- The `SpriteBundle` still had a `Handle<Image>` field. I've removed
this.
- Tests in `bevy_sprite` incorrectly added a `Handle<Image>` field
outside of the `Sprite` component.
- A few examples were still inserting `Handle`s, switched those to their
corresponding wrappers.
- 2 examples that were still querying for `Handle<Image>` were changed
to query `Sprite`
## Testing
- I've verified that the changed example work now
## Migration Guide
`Handle` can no longer be used as a `Component`. All existing Bevy types
using this pattern have been wrapped in their own semantically
meaningful type. You should do the same for any custom `Handle`
components your project needs.
The `Handle<MeshletMesh>` component is now `MeshletMesh3d`.
The `WithMeshletMesh` type alias has been removed. Use
`With<MeshletMesh3d>` instead.
# Objective
If a `Resource` implements `FromWorld` or `Default`, it's nicer to be
able to write:
```rust
let foo = world.get_resource_or_init::<Foo>();
```
Rather than:
```rust
let foo = world.get_resource_or_insert_with(Foo::default);
```
The latter is also not possible if a type implements `FromWorld` only,
and not `Default`.
## Solution
Added:
```rust
impl World {
pub fn get_resource_or_init<R: Resource + FromWorld>(&mut self) -> Mut<'_, R>;
}
```
Turns out all current in-engine uses of `get_resource_or_insert_with`
are exactly the above, so they've also been replaced.
## Testing
- Added a doc-test.
- Also added a doc-test for `World::get_resource_or_insert_with`.
In order to create texture atlases from other systems (custom game
solutions) that are compatible with the ones generated by the bevy
builders, it would be nice to have the interface be fully public. This
field is pub(crate). Unless there's a good reason, can we promote this
to pub?
Alternatives:
- Don't do it.
**Ready for review. Examples migration progress: 100%.**
# Objective
- Implement https://github.com/bevyengine/bevy/discussions/15014
## Solution
This implements [cart's
proposal](https://github.com/bevyengine/bevy/discussions/15014#discussioncomment-10574459)
faithfully except for one change. I separated `TextSpan` from
`TextSpan2d` because `TextSpan` needs to require the `GhostNode`
component, which is a `bevy_ui` component only usable by UI.
Extra changes:
- Added `EntityCommands::commands_mut` that returns a mutable reference.
This is a blocker for extension methods that return something other than
`self`. Note that `sickle_ui`'s `UiBuilder::commands` returns a mutable
reference for this reason.
## Testing
- [x] Text examples all work.
---
## Showcase
TODO: showcase-worthy
## Migration Guide
TODO: very breaking
### Accessing text spans by index
Text sections are now text sections on different entities in a
hierarchy, Use the new `TextReader` and `TextWriter` system parameters
to access spans by index.
Before:
```rust
fn refresh_text(mut query: Query<&mut Text, With<TimeText>>, time: Res<Time>) {
let text = query.single_mut();
text.sections[1].value = format_time(time.elapsed());
}
```
After:
```rust
fn refresh_text(
query: Query<Entity, With<TimeText>>,
mut writer: UiTextWriter,
time: Res<Time>
) {
let entity = query.single();
*writer.text(entity, 1) = format_time(time.elapsed());
}
```
### Iterating text spans
Text spans are now entities in a hierarchy, so the new `UiTextReader`
and `UiTextWriter` system parameters provide ways to iterate that
hierarchy. The `UiTextReader::iter` method will give you a normal
iterator over spans, and `UiTextWriter::for_each` lets you visit each of
the spans.
---------
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Another step towards #15716
- Remove trait implementations that are dependent on `Handle<T>` being a
`Component`
## Solution
- Remove unused `ExtractComponent` trait implementation for `Handle<T>`
- Remove unused `ExtractInstance` trait implementation for `AssetId`
- Although the `ExtractInstance` trait wasn't used, the `AssetId`s were
being stored inside of `ExtractedInstances` which has an
`ExtractInstance` trait bound on its contents.
I've upgraded the `RenderMaterialInstances` type alias to be its own
resource, identical to `ExtractedInstances<AssetId<M>>` to get around
that with minimal breakage.
## Testing
Tested `many_cubes`, rendering did not explode
# Objective
A bunch of code is used only if you care about the `Curve` trait. Put it
behind a feature so it can be ignored if wanted.
## Solution
Added a default feature `curve` to `bevy_math` which feature-gates the
`curve` module and internal integrations.
## Testing
Tested compiling with the feature enabled and disabled.
# Objective
Continue migration of bevy APIs to required components, following
guidance of https://hackmd.io/@bevy/required_components/
## Solution
- Make `Sprite` require `Transform` and `Visibility` and
`SyncToRenderWorld`
- move image and texture atlas handles into `Sprite`
- deprecate `SpriteBundle`
- remove engine uses of `SpriteBundle`
## Testing
ran cargo tests on bevy_sprite and tested several sprite examples.
---
## Migration Guide
Replace all uses of `SpriteBundle` with `Sprite`. There are several new
convenience constructors: `Sprite::from_image`,
`Sprite::from_atlas_image`, `Sprite::from_color`.
WARNING: use of `Handle<Image>` and `TextureAtlas` as components on
sprite entities will NO LONGER WORK. Use the fields on `Sprite` instead.
I would have removed the `Component` impls from `TextureAtlas` and
`Handle<Image>` except it is still used within ui. We should fix this
moving forward with the migration.
# Objective
- Closes#15752
Calling the functions `App::observe` and `World::observe` doesn't make
sense because you're not "observing" the `App` or `World`, you're adding
an observer that listens for an event that occurs *within* the `World`.
We should rename them to better fit this.
## Solution
Renames:
- `App::observe` -> `App::add_observer`
- `World::observe` -> `World::add_observer`
- `Commands::observe` -> `Commands::add_observer`
- `EntityWorldMut::observe_entity` -> `EntityWorldMut::observe`
(Note this isn't a breaking change as the original rename was introduced
earlier this cycle.)
## Testing
Reusing current tests.
# Objective
- The `scrolling_fog` example has a camera with the
`TemporalAntiAliasing` component, but it's missing the `Msaa::Off`
component, which leads to this warning being printed on current `main`:
```
WARN bevy_core_pipeline::taa: Temporal anti-aliasing requires MSAA to be disabled
```
## Solution
- This PR adds the `Msaa::Off` component to the example to explicitly
disable MSAA in favor of TAA.
# Objective
Fixes#15726
The extraction logic for components makes use of `FromReflect` to try
and ensure we have a concrete type for serialization. However, we did
not do the same for resources.
The reason we're seeing this for the glam types is that #15174 also made
a change to rely on the glam type's `Serialize` and `Deserialize` impls,
which I don't think should have been merged (I'll put up a PR addressing
this specifically soon).
## Solution
Use `FromReflect` on extracted resources.
## Testing
You can test locally by running:
```
cargo test --package bevy_scene
```
# Objective
Getting closer to the end! Another part of the required components
migration: reflection probes.
## Solution
As per the [proposal added by
Cart](https://hackmd.io/@bevy/required_components/%2FNmpIh0tGSiayGlswbfcEzw)
(Proposal 2), make `LightProbe` require `Transform` and `Visibility`,
and deprecate `ReflectionProbeBundle`.
Note that this proposal wasn't officially blessed yet, but it is the
only existing one that really works, so I implemented it here for
consideration.
## Testing
I ran the reflection probe example, and it appears to work.
---
## Migration Guide
`ReflectionProbeBundle` has been deprecated in favor of inserting the
`LightProbe` and `EnvironmentMapLight` components directly. Inserting
them will now automatically insert `Transform` and `Visibility`
components.
---------
Co-authored-by: Tim Blackbird <justthecooldude@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Fixes#15285
## Solution
`winit` sends resized to zero events when the window is minimized only
on Windows OS(rust-windowing/winit#2015).
This makes updating window viewport size to `(0, 0)` and panicking when
calculating aspect ratio.
~~So, just skip these kinds of events - resizing to (0, 0) when the
window is minimized - on Windows OS~~
Idially, the camera extraction excludes the cameras whose target size
width or height is zero here;
25bfa80e60/crates/bevy_render/src/camera/camera.rs (L1060-L1074)
but it seems that winit event loop sends resize events after extraction
and before post update schedule, so they might panics before the
extraction filters them out.
Alternatively, it might be possible to change event loop evaluating
order or defer them to the right schedule but I'm afraid that it might
cause some breaking changes, so just skip rendering logics for such
windows and they will be all filtered out by the extractions on the next
frame and thereafter.
## Testing
Running the example in the original issue and minimizing causes panic,
or just running `tests/window/minimising.rs` with `cargo run --example
minimising` panics without this PR and doesn't panics with this PR.
I think that we should run it in CI on Windows OS btw
# Objective
- Fixes (partially) #15701.
## Solution
- Use little-endian bytes over native-endian bytes where applicable.
## Testing
- Ran CI.
## Open Questions
- Should we config-gate these for big-endian targets? It looks like
there are [very few
targets](https://doc.rust-lang.org/nightly/rustc/platform-support.html)
that use big-endian.
# Objective
- Closes#15717
## Solution
- Wrap the handle in a new wrapper component: `AnimationGraphHandle`.
## Testing
Searched for all instances of `AnimationGraph` in the examples and
updated and tested those
## Migration Guide
`Handle<AnimationGraph>` is no longer a component. Instead, use the
`AnimationGraphHandle` component which contains a
`Handle<AnimationGraph>`.
