# Objective
- Choose LOD based on normal simplification error in addition to
position error
- Update meshoptimizer to 0.22, which has a bunch of simplifier
improvements
## Testing
- Did you test these changes? If so, how?
- Visualize normals, and compare LOD changes before and after. Normals
no longer visibly change as the LOD cut changes.
- Are there any parts that need more testing?
- No
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- Run the meshlet example in this PR and on main and move around to
change the LOD cut. Before running each example, in
meshlet_mesh_material.wgsl, replace `let color = vec3(rand_f(&rng),
rand_f(&rng), rand_f(&rng));` with `let color =
(vertex_output.world_normal + 1.0) / 2.0;`. Make sure to download the
appropriate bunny asset for each branch!
# Objective
clean up example get_single method, make code clean;
## Solution
- replace `Query` with `Single` Query
- remove `get_single` or `get_single_mut` condition block
# Objective
This example is really confusing to look at and tell at a glance whether
it's broken or not.
It's displaying a strange shape -- a cube with two vertices stretched in
a couple dimensions at an odd angle, and doing its vertex position
modification in a way where the intent isn't obvious.
## Solution
- Change the gltf geometry so that the object is a recognizable regular
shape
- Change the vertex modification so that the entire cube top is being
"lifted" from the cube
- Adjust colors, lighting, and camera location so we can see what's
going on
- Also remove some irrelevant shadow and environment map setup
## Before
## After
<img width="1280" alt="image"
src="https://github.com/user-attachments/assets/59cab60d-efbc-47c3-8688-e4544b462421">
Take a bunch more improvements from @zeux's nanite.cpp code.
* Use position-only vertices (discard other attributes) to determine
meshlet connectivity for grouping
* Rather than using the lock borders flag when simplifying meshlet
groups, provide the locked vertices ourselves. The lock borders flag
locks the entire border of the meshlet group, but really we only want to
lock the edges between meshlet groups - outwards facing edges are fine
to unlock. This gives a really significant increase to the DAG quality.
* Add back stuck meshlets (group has only a single meshlet,
simplification failed) to the simplification queue to allow them to get
used later on and have another attempt at simplifying
* Target 8 meshlets per group instead of 4 (second biggest improvement
after manual locks)
* Provide a seed to metis for deterministic meshlet building
* Misc other improvements
We can remove the usage of unsafe after the next upstream meshopt
release, but for now we need to use the ffi function directly. I'll do
another round of improvements later, mainly attribute-aware
simplification and using spatial weights for meshlet grouping.
Need to merge https://github.com/bevyengine/bevy/pull/15846 first.
# Objective
Bevy seems to want to standardize on "American English" spellings. Not
sure if this is laid out anywhere in writing, but see also #15947.
While perusing the docs for `typos`, I noticed that it has a `locale`
config option and tried it out.
## Solution
Switch to `en-us` locale in the `typos` config and run `typos -w`
## Migration Guide
The following methods or fields have been renamed from `*dependants*` to
`*dependents*`.
- `ProcessorAssetInfo::dependants`
- `ProcessorAssetInfos::add_dependant`
- `ProcessorAssetInfos::non_existent_dependants`
- `AssetInfo::dependants_waiting_on_load`
- `AssetInfo::dependants_waiting_on_recursive_dep_load`
- `AssetInfos::loader_dependants`
- `AssetInfos::remove_dependants_and_labels`
# 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
Fixes#15976
## Solution
I haven't been following the recent camera changes but on a whim I
inverted the scale and it restored the old behavior.
It seems that a similar inversion was done when migrating the
`pixel_grid_snap` example in #15976.
## Testing
`cargo run --example pbr`
# Objective
Fixes#15791.
As raised in #11022, scaling orthographic cameras is confusing! In Bevy
0.14, there were multiple completely redundant ways to do this, and no
clear guidance on which to use.
As a result, #15075 removed the `scale` field from
`OrthographicProjection` completely, solving the redundancy issue.
However, this resulted in an unintuitive API and a painful migration, as
discussed in #15791. Users simply want to change a single parameter to
zoom, rather than deal with the irrelevant details of how the camera is
being scaled.
## Solution
This PR reverts #15075, and takes an alternate, more nuanced approach to
the redundancy problem. `ScalingMode::WindowSize` was by far the biggest
offender. This was the default variant, and stored a float that was
*fully* redundant to setting `scale`.
All of the other variants contained meaningful semantic information and
had an intuitive scale. I could have made these unitless, storing an
aspect ratio, but this would have been a worse API and resulted in a
pointlessly painful migration.
In the course of this work I've also:
- improved the documentation to explain that you should just set `scale`
to zoom cameras
- swapped to named fields for all of the variants in `ScalingMode` for
more clarity about the parameter meanings
- substantially improved the `projection_zoom` example
- removed the footgunny `Mul` and `Div` impls for `ScalingMode`,
especially since these no longer have the intended effect on
`ScalingMode::WindowSize`.
- removed a rounding step because this is now redundant 🎉
## Testing
I've tested these changes as part of my work in the `projection_zoom`
example, and things seem to work fine.
## Migration Guide
`ScalingMode` has been refactored for clarity, especially on how to zoom
orthographic cameras and their projections:
- `ScalingMode::WindowSize` no longer stores a float, and acts as if its
value was 1. Divide your camera's scale by any previous value to achieve
identical results.
- `ScalingMode::FixedVertical` and `FixedHorizontal` now use named
fields.
---------
Co-authored-by: MiniaczQ <xnetroidpl@gmail.com>
# Objective
Adjust instruction text in some newer examples to match the [example
visual
guidelines](https://bevyengine.org/learn/contribute/helping-out/creating-examples/#visual-guidelines).
## Solution
Move text 12px from edge of screen
## Testing
```
cargo run --example alter_mesh
cargo run --example alter_sprite
cargo run --example camera_orbit
cargo run --example projection_zoom
cargo run --example irradiance_volumes
cargo run --example log_layers_ecs
cargo run --example multi_asset_sync
cargo run --example multiple_windows
cargo run --example order_independent_transparency
```
## Additional information
This isn't comprehensive, just the most trivial cases. I'll double check
my notes and probably follow up with an issue to look into visual
guidelines for a few other examples.
Fixes#15834
## Migration Guide
The APIs of `Time`, `Timer` and `Stopwatch` have been cleaned up for
consistency with each other and the standard library's `Duration` type.
The following methods have been renamed:
- `Stowatch::paused` -> `Stopwatch::is_paused`
- `Time::elapsed_seconds` -> `Time::elasped_secs` (including `_f64` and
`_wrapped` variants)
# Objective
Cleanup naming and docs, add missing migration guide after #15591
All text root nodes now use `Text` (UI) / `Text2d`.
All text readers/writers use `Text<Type>Reader`/`Text<Type>Writer`
convention.
---
## Migration Guide
Doubles as #15591 migration guide.
Text bundles (`TextBundle` and `Text2dBundle`) were removed in favor of
`Text` and `Text2d`.
Shared configuration fields were replaced with `TextLayout`, `TextFont`
and `TextColor` components.
Just `TextBundle`'s additional field turned into `TextNodeFlags`
component,
while `Text2dBundle`'s additional fields turned into `TextBounds` and
`Anchor` components.
Text sections were removed in favor of hierarchy-based approach.
For root text entities with `Text` or `Text2d` components, child
entities with `TextSpan` will act as additional text sections.
To still access text spans by index, use the new `TextUiReader`,
`Text2dReader` and `TextUiWriter`, `Text2dWriter` system parameters.
# Objective
The type `AssetLoadError` has `PartialEq` and `Eq` impls, which is
problematic due to the fact that the `AssetLoaderError` and
`AddAsyncError` variants lie in their impls: they will return `true` for
any `Box<dyn Error>` with the same `TypeId`, even if the actual value is
different. This can lead to subtle bugs if a user relies on the equality
comparison to ensure that two values are equal.
The same is true for `DependencyLoadState`,
`RecursiveDependencyLoadState`.
More generally, it is an anti-pattern for large error types involving
dynamic dispatch, such as `AssetLoadError`, to have equality
comparisons. Directly comparing two errors for equality is usually not
desired -- if some logic needs to branch based on the value of an error,
it is usually more correct to check for specific variants and inspect
their fields.
As far as I can tell, the only reason these errors have equality
comparisons is because the `LoadState` enum wraps `AssetLoadError` for
its `Failed` variant. This equality comparison is only used to check for
`== LoadState::Loaded`, which we can easily replace with an `is_loaded`
method.
## Solution
Remove the `{Partial}Eq` impls from `LoadState`, which also allows us to
remove it from the error types.
## Migration Guide
The types `bevy_asset::AssetLoadError` and `bevy_asset::LoadState` no
longer support equality comparisons. If you need to check for an asset's
load state, consider checking for a specific variant using
`LoadState::is_loaded` or the `matches!` macro. Similarly, consider
using the `matches!` macro to check for specific variants of the
`AssetLoadError` type if you need to inspect the value of an asset load
error in your code.
`DependencyLoadState` and `RecursiveDependencyLoadState` are not
released yet, so no migration needed,
---------
Co-authored-by: Joseph <21144246+JoJoJet@users.noreply.github.com>
# Objective
- closes#15866
## Solution
- Simply migrate where possible.
## Testing
- Expect that CI will do most of the work. Examples is another way of
testing this, as most of the work is in that area.
---
## Notes
For now, this PR doesn't migrate `QueryState::single` and friends as for
now, this look like another issue. So for example, QueryBuilders that
used single or `World::query` that used single wasn't migrated. If there
is a easy way to migrate those, please let me know.
Most of the uses of `Query::single` were removed, the only other uses
that I found was related to tests of said methods, so will probably be
removed when we remove `Query::single`.
# Objective
- Required components replace bundles, but `SpatialBundle` is yet to be
deprecated
## Solution
- Deprecate `SpatialBundle`
- Insert `Transform` and `Visibility` instead in examples using it
- In `spawn` or `insert` inserting a default `Transform` or `Visibility`
with component already requiring either, remove those components from
the tuple
## Testing
- Did you test these changes? If so, how?
Yes, I ran the examples I changed and tests
- Are there any parts that need more testing?
The `gamepad_viewer` and and `custom_shader_instancing` examples don't
work as intended due to entirely unrelated code, didn't check main.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
Run examples, or just check that all spawned values are identical
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
Linux, wayland trough x11 (cause that's the default feature)
---
## Migration Guide
`SpatialBundle` is now deprecated, insert `Transform` and `Visibility`
instead which will automatically insert all other components that were
in the bundle. If you do not specify these values and any other
components in your `spawn`/`insert` call already requires either of
these components you can leave that one out.
before:
```rust
commands.spawn(SpatialBundle::default());
```
after:
```rust
commands.spawn((Transform::default(), Visibility::default());
```
# Objective
Closes#15545.
`bevy_picking` supports UI and sprite picking, but not mesh picking.
Being able to pick meshes would be extremely useful for various games,
tools, and our own examples, as well as scene editors and inspectors.
So, we need a mesh picking backend!
Luckily,
[`bevy_mod_picking`](https://github.com/aevyrie/bevy_mod_picking) (which
`bevy_picking` is based on) by @aevyrie already has a [backend for
it](74f0c3c0fb/backends/bevy_picking_raycast/src/lib.rs)
using [`bevy_mod_raycast`](https://github.com/aevyrie/bevy_mod_raycast).
As a side product of adding mesh picking, we also get support for
performing ray casts on meshes!
## Solution
Upstream a large chunk of the immediate-mode ray casting functionality
from `bevy_mod_raycast`, and add a mesh picking backend based on
`bevy_mod_picking`. Huge thanks to @aevyrie who did all the hard work on
these incredible crates!
All meshes are pickable by default. Picking can be disabled for
individual entities by adding `PickingBehavior::IGNORE`, like normal.
Or, if you want mesh picking to be entirely opt-in, you can set
`MeshPickingBackendSettings::require_markers` to `true` and add a
`RayCastPickable` component to the desired camera and target entities.
You can also use the new `MeshRayCast` system parameter to cast rays
into the world manually:
```rust
fn ray_cast_system(mut ray_cast: MeshRayCast, foo_query: Query<(), With<Foo>>) {
let ray = Ray3d::new(Vec3::ZERO, Dir3::X);
// Only ray cast against entities with the `Foo` component.
let filter = |entity| foo_query.contains(entity);
// Never early-exit. Note that you can change behavior per-entity.
let early_exit_test = |_entity| false;
// Ignore the visibility of entities. This allows ray casting hidden entities.
let visibility = RayCastVisibility::Any;
let settings = RayCastSettings::default()
.with_filter(&filter)
.with_early_exit_test(&early_exit_test)
.with_visibility(visibility);
// Cast the ray with the settings, returning a list of intersections.
let hits = ray_cast.cast_ray(ray, &settings);
}
```
This is largely a direct port, but I did make several changes to match
our APIs better, remove things we don't need or that I think are
unnecessary, and do some general improvements to code quality and
documentation.
### Changes Relative to `bevy_mod_raycast` and `bevy_mod_picking`
- Every `Raycast` and "raycast" has been renamed to `RayCast` and "ray
cast" (similar reasoning as the "Naming" section in #15724)
- `Raycast` system param has been renamed to `MeshRayCast` to avoid
naming conflicts and to be explicit that it is not for colliders
- `RaycastBackend` has been renamed to `MeshPickingBackend`
- `RayCastVisibility` variants are now `Any`, `Visible`, and
`VisibleInView` instead of `Ignore`, `MustBeVisible`, and
`MustBeVisibleAndInView`
- `NoBackfaceCulling` has been renamed to `RayCastBackfaces`, to avoid
implying that it affects the rendering of backfaces for meshes (it
doesn't)
- `SimplifiedMesh` and `RayCastBackfaces` live near other ray casting
API types, not in their own 10 LoC module
- All intersection logic and types are in the same `intersections`
module, not split across several modules
- Some intersection types have been renamed to be clearer and more
consistent
- `IntersectionData` -> `RayMeshHit`
- `RayHit` -> `RayTriangleHit`
- General documentation and code quality improvements
### Removed / Not Ported
- Removed unused ray helpers and types, like `PrimitiveIntersection`
- Removed getters on intersection types, and made their properties
public
- There is no `2d` feature, and `Raycast::mesh_query` and
`Raycast::mesh2d_query` have been merged into `MeshRayCast::mesh_query`,
which handles both 2D and 3D
- I assume this existed previously because `Mesh2dHandle` used to be in
`bevy_sprite`. Now both the 2D and 3D mesh are in `bevy_render`.
- There is no `debug` feature or ray debug rendering
- There is no deferred API (`RaycastSource`)
- There is no `CursorRayPlugin` (the picking backend handles this)
### Note for Reviewers
In case it's helpful, the [first
commit](281638ef10)
here is essentially a one-to-one port. The rest of the commits are
primarily refactoring and cleaning things up in the ways listed earlier,
as well as changes to the module structure.
It may also be useful to compare the original [picking
backend](74f0c3c0fb/backends/bevy_picking_raycast/src/lib.rs)
and [`bevy_mod_raycast`](https://github.com/aevyrie/bevy_mod_raycast) to
this PR. Feel free to mention if there are any changes that I should
revert or something I should not include in this PR.
## Testing
I tested mesh picking and relevant components in some examples, for both
2D and 3D meshes, and added a new `mesh_picking` example. I also
~~stole~~ ported over the [ray-mesh intersection
benchmark](dbc5ef32fe/benches/ray_mesh_intersection.rs)
from `bevy_mod_raycast`.
---
## Showcase
Below is a version of the `2d_shapes` example modified to demonstrate 2D
mesh picking. This is not included in this PR.
https://github.com/user-attachments/assets/7742528c-8630-4c00-bacd-81576ac432bf
And below is the new `mesh_picking` example:
https://github.com/user-attachments/assets/b65c7a5a-fa3a-4c2d-8bbd-e7a2c772986e
There is also a really cool new `mesh_ray_cast` example ported over from
`bevy_mod_raycast`:
https://github.com/user-attachments/assets/3c5eb6c0-bd94-4fb0-bec6-8a85668a06c9
---------
Co-authored-by: Aevyrie <aevyrie@gmail.com>
Co-authored-by: Trent <2771466+tbillington@users.noreply.github.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
# Objective
Currently text is recomputed unnecessarily on any changes to its color,
which is extremely expensive.
## Solution
Split up `TextStyle` into two separate components `TextFont` and
`TextColor`.
## Testing
I added this system to `many_buttons`:
```rust
fn set_text_colors_changed(mut colors: Query<&mut TextColor>) {
for mut text_color in colors.iter_mut() {
text_color.set_changed();
}
}
```
reports ~4fps on main, ~50fps with this PR.
## Migration Guide
`TextStyle` has been renamed to `TextFont` and its `color` field has
been moved to a separate component named `TextColor` which newtypes
`Color`.
# Objective
Fixes a mistake in the migration done in #15591.
## Solution
Restore a line of instructions that was accidentally dropped.
## Testing
`cargo run --example motion_blur`
Tested that instructions make sense and text updates correctly when keys
are pressed.
# 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
- 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.
**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
- 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
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
- 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>`.
# Objective
Fixes#15560
Fixes (most of) #15570
Currently a lot of examples (and presumably some user code) depend on
toggling certain render features by adding/removing a single component
to an entity, e.g. `SpotLight` to toggle a light. Because of the
retained render world this no longer works: Extract will add any new
components, but when it is removed the entity persists unchanged in the
render world.
## Solution
Add `SyncComponentPlugin<C: Component>` that registers
`SyncToRenderWorld` as a required component for `C`, and adds a
component hook that will clear all components from the render world
entity when `C` is removed. We add this plugin to
`ExtractComponentPlugin` which fixes most instances of the problem. For
custom extraction logic we can manually add `SyncComponentPlugin` for
that component.
We also rename `WorldSyncPlugin` to `SyncWorldPlugin` so we start a
naming convention like all the `Extract` plugins.
In this PR I also fixed a bunch of breakage related to the retained
render world, stemming from old code that assumed that `Entity` would be
the same in both worlds.
I found that using the `RenderEntity` wrapper instead of `Entity` in
data structures when referring to render world entities makes intent
much clearer, so I propose we make this an official pattern.
## Testing
Run examples like
```
cargo run --features pbr_multi_layer_material_textures --example clearcoat
cargo run --example volumetric_fog
```
and see that they work, and that toggles work correctly. But really we
should test every single example, as we might not even have caught all
the breakage yet.
---
## Migration Guide
The retained render world notes should be updated to explain this edge
case and `SyncComponentPlugin`
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Trashtalk217 <trashtalk217@gmail.com>
# Objective
- Prepare for streaming by storing vertex data per-meshlet, rather than
per-mesh (this means duplicating vertices per-meshlet)
- Compress vertex data to reduce the cost of this
## Solution
The important parts are in from_mesh.rs, the changes to the Meshlet type
in asset.rs, and the changes in meshlet_bindings.wgsl. Everything else
is pretty secondary/boilerplate/straightforward changes.
- Positions are quantized in centimeters with a user-provided power of 2
factor (ideally auto-determined, but that's a TODO for the future),
encoded as an offset relative to the minimum value within the meshlet,
and then stored as a packed list of bits using the minimum number of
bits needed for each vertex position channel for that meshlet
- E.g. quantize positions (lossly, throws away precision that's not
needed leading to using less bits in the bitstream encoding)
- Get the min/max quantized value of each X/Y/Z channel of the quantized
positions within a meshlet
- Encode values relative to the min value of the meshlet. E.g. convert
from [min, max] to [0, max - min]
- The new max value in the meshlet is (max - min), which only takes N
bits, so we only need N bits to store each channel within the meshlet
(lossless)
- We can store the min value and that it takes N bits per channel in the
meshlet metadata, and reconstruct the position from the bitstream
- Normals are octahedral encoded and than snorm2x16 packed and stored as
a single u32.
- Would be better to implement the precise variant of octhedral encoding
for extra precision (no extra decode cost), but decided to keep it
simple for now and leave that as a followup
- Tried doing a quantizing and bitstream encoding scheme like I did for
positions, but struggled to get it smaller. Decided to go with this for
simplicity for now
- UVs are uncompressed and take a full 64bits per vertex which is
expensive
- In the future this should be improved
- Tangents, as of the previous PR, are not explicitly stored and are
instead derived from screen space gradients
- While I'm here, split up MeshletMeshSaverLoader into two separate
types
Other future changes include implementing a smaller encoding of triangle
data (3 u8 indices = 24 bits per triangle currently), and more
disk-oriented compression schemes.
References:
* "A Deep Dive into UE5's Nanite Virtualized Geometry"
https://advances.realtimerendering.com/s2021/Karis_Nanite_SIGGRAPH_Advances_2021_final.pdf#page=128
(also available on youtube)
* "Towards Practical Meshlet Compression"
https://arxiv.org/pdf/2404.06359
* "Vertex quantization in Omniforce Game Engine"
https://daniilvinn.github.io/2024/05/04/omniforce-vertex-quantization.html
## Testing
- Did you test these changes? If so, how?
- Converted the stanford bunny, and rendered it with a debug material
showing normals, and confirmed that it's identical to what's on main.
EDIT: See additional testing in the comments below.
- Are there any parts that need more testing?
- Could use some more size comparisons on various meshes, and testing
different quantization factors. Not sure if 4 is a good default. EDIT:
See additional testing in the comments below.
- Also did not test runtime performance of the shaders. EDIT: See
additional testing in the comments below.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- Use my unholy script, replacing the meshlet example
https://paste.rs/7xQHk.rs (must make MeshletMesh fields pub instead of
pub crate, must add lz4_flex as a dev-dependency) (must compile with
meshlet and meshlet_processor features, mesh must have only positions,
normals, and UVs, no vertex colors or tangents)
---
## Migration Guide
- TBD by JMS55 at the end of the release
# Objective
- Adds better comments and includes an example where the aspect ratio
between `size` and `full_size` differ
- Fixes#15576
## Solution
- Viewports are dynamically scaled to window size
## Testing
- Tested with moving the window around and by manually setting the
window scaling factor
- Just to make sure nothing else is going on, someone on macOS should
also test this
## Showcase
Since calculating padding from window size is a hassle, the example now
looks a bit more squished together:
# Objective
- Alpha blending can easily fail in many situations and requires sorting
on the cpu
## Solution
- Implement order independent transparency (OIT) as an alternative to
alpha blending
- The implementation uses 2 passes
- The first pass records all the fragments colors and position to a
buffer that is the size of N layers * the render target resolution.
- The second pass sorts the fragments, blends them and draws them to the
screen. It also currently does manual depth testing because early-z
fails in too many cases in the first pass.
## Testing
- We've been using this implementation at foresight in production for
many months now and we haven't had any issues related to OIT.
---
## Showcase
## Future work
- Add an example showing how to use OIT for a custom material
- Next step would be to implement a per-pixel linked list to reduce
memory use
- I'd also like to investigate using a BinnedRenderPhase instead of a
SortedRenderPhase. If it works, it would make the transparent pass
significantly faster.
---------
Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
Co-authored-by: Charlotte McElwain <charlotte.c.mcelwain@gmail.com>
This example was missed during the port to required components for
meshes and materials.
Easy fix, I checked that it works as it did in the PR that added the
example (#13912).
# Objective
Yet another PR for migrating stuff to required components. This time,
cameras!
## Solution
As per the [selected
proposal](https://hackmd.io/tsYID4CGRiWxzsgawzxG_g#Combined-Proposal-1-Selected),
deprecate `Camera2dBundle` and `Camera3dBundle` in favor of `Camera2d`
and `Camera3d`.
Adding a `Camera` without `Camera2d` or `Camera3d` now logs a warning,
as suggested by Cart [on
Discord](https://discord.com/channels/691052431525675048/1264881140007702558/1291506402832945273).
I would personally like cameras to work a bit differently and be split
into a few more components, to avoid some footguns and confusing
semantics, but that is more controversial, and shouldn't block this core
migration.
## Testing
I ran a few 2D and 3D examples, and tried cameras with and without
render graphs.
---
## Migration Guide
`Camera2dBundle` and `Camera3dBundle` have been deprecated in favor of
`Camera2d` and `Camera3d`. Inserting them will now also insert the other
components required by them automatically.
The components needed for `DirectionalLight` are added automatically
since #15554
`create_point_light` already existed and returns a `PointLight` with
these same settings
Early implementation. I still have to fix the documentation and consider
writing a small migration guide.
Questions left to answer:
* [x] should thickness be an overridable constant?
* [x] is there a better way to implement `Eq`/`Hash` for `SSAOMethod`?
* [x] do we want to keep the linear sampler for the depth texture?
* [x] is there a better way to separate the logic than preprocessor
macros?
## Migration guide
SSAO algorithm was changed from GTAO to VBAO (visibility bitmasks). A
new field, `constant_object_thickness`, was added to
`ScreenSpaceAmbientOcclusion`. `ScreenSpaceAmbientOcclusion` also lost
its `Eq` and `Hash` implementations.
---------
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
As discussed in #15521
- Partial revert of #14897, reverting the change to the methods to
consume `self`
- The `insert_if` method is kept
The migration guide of #14897 should be removed
Closes#15521
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Again, a step forward in the migration to required components: a bunch
of camera rendering cormponents!
Note that this does not include the camera components themselves yet,
because the naming and API for `Camera` hasn't been fully decided yet.
## Solution
As per the [selected
proposals](https://hackmd.io/@bevy/required_components/%2FpiqD9GOdSFKZZGzzh3C7Uw):
- Deprecate `MotionBlurBundle` in favor of the `MotionBlur` component
- Deprecate `TemporalAntiAliasBundle` in favor of the
`TemporalAntiAliasing` component
- Deprecate `ScreenSpaceAmbientOcclusionBundle` in favor of the
`ScreenSpaceAmbientOcclusion` component
- Deprecate `ScreenSpaceReflectionsBundle` in favor of the
`ScreenSpaceReflections` component
---
## Migration Guide
`MotionBlurBundle`, `TemporalAntiAliasBundle`,
`ScreenSpaceAmbientOcclusionBundle`, and `ScreenSpaceReflectionsBundle`
have been deprecated in favor of the `MotionBlur`,
`TemporalAntiAliasing`, `ScreenSpaceAmbientOcclusion`, and
`ScreenSpaceReflections` components instead. Inserting them will now
also insert the other components required by them automatically.
# Objective
A step in the migration to required components: scenes!
## Solution
As per the [selected
proposal](https://hackmd.io/@bevy/required_components/%2FPJtNGVMMQhyM0zIvCJSkbA):
- Deprecate `SceneBundle` and `DynamicSceneBundle`.
- Add `SceneRoot` and `DynamicSceneRoot` components, which wrap a
`Handle<Scene>` and `Handle<DynamicScene>` respectively.
## Migration Guide
Asset handles for scenes and dynamic scenes must now be wrapped in the
`SceneRoot` and `DynamicSceneRoot` components. Raw handles as components
no longer spawn scenes.
Additionally, `SceneBundle` and `DynamicSceneBundle` have been
deprecated. Instead, use the scene components directly.
Previously:
```rust
let model_scene = asset_server.load(GltfAssetLabel::Scene(0).from_asset("model.gltf"));
commands.spawn(SceneBundle {
scene: model_scene,
transform: Transform::from_xyz(-4.0, 0.0, -3.0),
..default()
});
```
Now:
```rust
let model_scene = asset_server.load(GltfAssetLabel::Scene(0).from_asset("model.gltf"));
commands.spawn((
SceneRoot(model_scene),
Transform::from_xyz(-4.0, 0.0, -3.0),
));
```
# Objective
A big step in the migration to required components: meshes and
materials!
## Solution
As per the [selected
proposal](https://hackmd.io/@bevy/required_components/%2Fj9-PnF-2QKK0on1KQ29UWQ):
- Deprecate `MaterialMesh2dBundle`, `MaterialMeshBundle`, and
`PbrBundle`.
- Add `Mesh2d` and `Mesh3d` components, which wrap a `Handle<Mesh>`.
- Add `MeshMaterial2d<M: Material2d>` and `MeshMaterial3d<M: Material>`,
which wrap a `Handle<M>`.
- Meshes *without* a mesh material should be rendered with a default
material. The existence of a material is determined by
`HasMaterial2d`/`HasMaterial3d`, which is required by
`MeshMaterial2d`/`MeshMaterial3d`. This gets around problems with the
generics.
Previously:
```rust
commands.spawn(MaterialMesh2dBundle {
mesh: meshes.add(Circle::new(100.0)).into(),
material: materials.add(Color::srgb(7.5, 0.0, 7.5)),
transform: Transform::from_translation(Vec3::new(-200., 0., 0.)),
..default()
});
```
Now:
```rust
commands.spawn((
Mesh2d(meshes.add(Circle::new(100.0))),
MeshMaterial2d(materials.add(Color::srgb(7.5, 0.0, 7.5))),
Transform::from_translation(Vec3::new(-200., 0., 0.)),
));
```
If the mesh material is missing, previously nothing was rendered. Now,
it renders a white default `ColorMaterial` in 2D and a
`StandardMaterial` in 3D (this can be overridden). Below, only every
other entity has a material:
Why white? This is still open for discussion, but I think white makes
sense for a *default* material, while *invalid* asset handles pointing
to nothing should have something like a pink material to indicate that
something is broken (I don't handle that in this PR yet). This is kind
of a mix of Godot and Unity: Godot just renders a white material for
non-existent materials, while Unity renders nothing when no materials
exist, but renders pink for invalid materials. I can also change the
default material to pink if that is preferable though.
## Testing
I ran some 2D and 3D examples to test if anything changed visually. I
have not tested all examples or features yet however. If anyone wants to
test more extensively, it would be appreciated!
## Implementation Notes
- The relationship between `bevy_render` and `bevy_pbr` is weird here.
`bevy_render` needs `Mesh3d` for its own systems, but `bevy_pbr` has all
of the material logic, and `bevy_render` doesn't depend on it. I feel
like the two crates should be refactored in some way, but I think that's
out of scope for this PR.
- I didn't migrate meshlets to required components yet. That can
probably be done in a follow-up, as this is already a huge PR.
- It is becoming increasingly clear to me that we really, *really* want
to disallow raw asset handles as components. They caused me a *ton* of
headache here already, and it took me a long time to find every place
that queried for them or inserted them directly on entities, since there
were no compiler errors for it. If we don't remove the `Component`
derive, I expect raw asset handles to be a *huge* footgun for users as
we transition to wrapper components, especially as handles as components
have been the norm so far. I personally consider this to be a blocker
for 0.15: we need to migrate to wrapper components for asset handles
everywhere, and remove the `Component` derive. Also see
https://github.com/bevyengine/bevy/issues/14124.
---
## Migration Guide
Asset handles for meshes and mesh materials must now be wrapped in the
`Mesh2d` and `MeshMaterial2d` or `Mesh3d` and `MeshMaterial3d`
components for 2D and 3D respectively. Raw handles as components no
longer render meshes.
Additionally, `MaterialMesh2dBundle`, `MaterialMeshBundle`, and
`PbrBundle` have been deprecated. Instead, use the mesh and material
components directly.
Previously:
```rust
commands.spawn(MaterialMesh2dBundle {
mesh: meshes.add(Circle::new(100.0)).into(),
material: materials.add(Color::srgb(7.5, 0.0, 7.5)),
transform: Transform::from_translation(Vec3::new(-200., 0., 0.)),
..default()
});
```
Now:
```rust
commands.spawn((
Mesh2d(meshes.add(Circle::new(100.0))),
MeshMaterial2d(materials.add(Color::srgb(7.5, 0.0, 7.5))),
Transform::from_translation(Vec3::new(-200., 0., 0.)),
));
```
If the mesh material is missing, a white default material is now used.
Previously, nothing was rendered if the material was missing.
The `WithMesh2d` and `WithMesh3d` query filter type aliases have also
been removed. Simply use `With<Mesh2d>` or `With<Mesh3d>`.
---------
Co-authored-by: Tim Blackbird <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Another part of the migration to required components: fog volumes!
## Solution
Deprecate `FogVolumeBundle` and make `FogVolume` require `Transform` and
`Visibility`, as per the [chosen
proposal](https://hackmd.io/@bevy/required_components/%2FcO7JPSAQR5G0J_j5wNwtOQ).
---
## Migration Guide
Replace all insertions of `FogVolumeBundle` with the `Visibility`
component. The other components required by it will now be inserted
automatically.
# Objective
- This PR fixes#12488
## Solution
- This PR adds a new property to `Camera` that emulates the
functionality of the
[setViewOffset()](https://threejs.org/docs/#api/en/cameras/PerspectiveCamera.setViewOffset)
API in three.js.
- When set, the perspective and orthographic projections will restrict
the visible area of the camera to a part of the view frustum defined by
`offset` and `size`.
## Testing
- In the new `camera_sub_view` example, a fixed, moving and control sub
view is created for both perspective and orthographic projection
- Run the example with `cargo run --example camera_sub_view`
- The code can be tested by adding a `SubCameraView` to a camera
---
## Showcase
- Left Half: Perspective Projection
- Right Half: Orthographic Projection
- Small boxes in order:
- Sub view of the left half of the full image
- Sub view moving from the top left to the bottom right of the full
image
- Sub view of the full image (acting as a control)
- Large box: No sub view
<details>
<summary>Shortened camera setup of `camera_sub_view` example</summary>
```rust
// Main perspective Camera
commands.spawn(Camera3dBundle {
transform,
..default()
});
// Perspective camera left half
commands.spawn(Camera3dBundle {
camera: Camera {
sub_camera_view: Some(SubCameraView {
// Set the sub view camera to the left half of the full image
full_size: uvec2(500, 500),
offset: ivec2(0, 0),
size: uvec2(250, 500),
}),
order: 1,
..default()
},
transform,
..default()
});
// Perspective camera moving
commands.spawn((
Camera3dBundle {
camera: Camera {
sub_camera_view: Some(SubCameraView {
// Set the sub view camera to a fifth of the full view and
// move it in another system
full_size: uvec2(500, 500),
offset: ivec2(0, 0),
size: uvec2(100, 100),
}),
order: 2,
..default()
},
transform,
..default()
},
MovingCameraMarker,
));
// Perspective camera control
commands.spawn(Camera3dBundle {
camera: Camera {
sub_camera_view: Some(SubCameraView {
// Set the sub view to the full image, to ensure that it matches
// the projection without sub view
full_size: uvec2(450, 450),
offset: ivec2(0, 0),
size: uvec2(450, 450),
}),
order: 3,
..default()
},
transform,
..default()
});
// Main orthographic camera
commands.spawn(Camera3dBundle {
projection: OrthographicProjection {
...
}
.into(),
camera: Camera {
order: 4,
..default()
},
transform,
..default()
});
// Orthographic camera left half
commands.spawn(Camera3dBundle {
projection: OrthographicProjection {
...
}
.into(),
camera: Camera {
sub_camera_view: Some(SubCameraView {
// Set the sub view camera to the left half of the full image
full_size: uvec2(500, 500),
offset: ivec2(0, 0),
size: uvec2(250, 500),
}),
order: 5,
..default()
},
transform,
..default()
});
// Orthographic camera moving
commands.spawn((
Camera3dBundle {
projection: OrthographicProjection {
...
}
.into(),
camera: Camera {
sub_camera_view: Some(SubCameraView {
// Set the sub view camera to a fifth of the full view and
// move it in another system
full_size: uvec2(500, 500),
offset: ivec2(0, 0),
size: uvec2(100, 100),
}),
order: 6,
..default()
},
transform,
..default()
},
MovingCameraMarker,
));
// Orthographic camera control
commands.spawn(Camera3dBundle {
projection: OrthographicProjection {
...
}
.into(),
camera: Camera {
sub_camera_view: Some(SubCameraView {
// Set the sub view to the full image, to ensure that it matches
// the projection without sub view
full_size: uvec2(450, 450),
offset: ivec2(0, 0),
size: uvec2(450, 450),
}),
order: 7,
..default()
},
transform,
..default()
});
```
</details>
# Objective
Another step in the migration to required components: lights!
Note that this does not include `EnvironmentMapLight` or reflection
probes yet, because their API hasn't been fully chosen yet.
## Solution
As per the [selected
proposals](https://hackmd.io/@bevy/required_components/%2FLLnzwz9XTxiD7i2jiUXkJg):
- Deprecate `PointLightBundle` in favor of the `PointLight` component
- Deprecate `SpotLightBundle` in favor of the `PointLight` component
- Deprecate `DirectionalLightBundle` in favor of the `DirectionalLight`
component
## Testing
I ran some examples with lights.
---
## Migration Guide
`PointLightBundle`, `SpotLightBundle`, and `DirectionalLightBundle` have
been deprecated. Use the `PointLight`, `SpotLight`, and
`DirectionalLight` components instead. Adding them will now insert the
other components required by them automatically.
- Adopted from #14449
- Still fixes#12144.
## Migration Guide
The retained render world is a complex change: migrating might take one
of a few different forms depending on the patterns you're using.
For every example, we specify in which world the code is run. Most of
the changes affect render world code, so for the average Bevy user who's
using Bevy's high-level rendering APIs, these changes are unlikely to
affect your code.
### Spawning entities in the render world
Previously, if you spawned an entity with `world.spawn(...)`,
`commands.spawn(...)` or some other method in the rendering world, it
would be despawned at the end of each frame. In 0.15, this is no longer
the case and so your old code could leak entities. This can be mitigated
by either re-architecting your code to no longer continuously spawn
entities (like you're used to in the main world), or by adding the
`bevy_render::world_sync::TemporaryRenderEntity` component to the entity
you're spawning. Entities tagged with `TemporaryRenderEntity` will be
removed at the end of each frame (like before).
### Extract components with `ExtractComponentPlugin`
```
// main world
app.add_plugins(ExtractComponentPlugin::<ComponentToExtract>::default());
```
`ExtractComponentPlugin` has been changed to only work with synced
entities. Entities are automatically synced if `ComponentToExtract` is
added to them. However, entities are not "unsynced" if any given
`ComponentToExtract` is removed, because an entity may have multiple
components to extract. This would cause the other components to no
longer get extracted because the entity is not synced.
So be careful when only removing extracted components from entities in
the render world, because it might leave an entity behind in the render
world. The solution here is to avoid only removing extracted components
and instead despawn the entire entity.
### Manual extraction using `Extract<Query<(Entity, ...)>>`
```rust
// in render world, inspired by bevy_pbr/src/cluster/mod.rs
pub fn extract_clusters(
mut commands: Commands,
views: Extract<Query<(Entity, &Clusters, &Camera)>>,
) {
for (entity, clusters, camera) in &views {
// some code
commands.get_or_spawn(entity).insert(...);
}
}
```
One of the primary consequences of the retained rendering world is that
there's no longer a one-to-one mapping from entity IDs in the main world
to entity IDs in the render world. Unlike in Bevy 0.14, Entity 42 in the
main world doesn't necessarily map to entity 42 in the render world.
Previous code which called `get_or_spawn(main_world_entity)` in the
render world (`Extract<Query<(Entity, ...)>>` returns main world
entities). Instead, you should use `&RenderEntity` and
`render_entity.id()` to get the correct entity in the render world. Note
that this entity does need to be synced first in order to have a
`RenderEntity`.
When performing manual abstraction, this won't happen automatically
(like with `ExtractComponentPlugin`) so add a `SyncToRenderWorld` marker
component to the entities you want to extract.
This results in the following code:
```rust
// in render world, inspired by bevy_pbr/src/cluster/mod.rs
pub fn extract_clusters(
mut commands: Commands,
views: Extract<Query<(&RenderEntity, &Clusters, &Camera)>>,
) {
for (render_entity, clusters, camera) in &views {
// some code
commands.get_or_spawn(render_entity.id()).insert(...);
}
}
// in main world, when spawning
world.spawn(Clusters::default(), Camera::default(), SyncToRenderWorld)
```
### Looking up `Entity` ids in the render world
As previously stated, there's now no correspondence between main world
and render world `Entity` identifiers.
Querying for `Entity` in the render world will return the `Entity` id in
the render world: query for `MainEntity` (and use its `id()` method) to
get the corresponding entity in the main world.
This is also a good way to tell the difference between synced and
unsynced entities in the render world, because unsynced entities won't
have a `MainEntity` component.
---------
Co-authored-by: re0312 <re0312@outlook.com>
Co-authored-by: re0312 <45868716+re0312@users.noreply.github.com>
Co-authored-by: Periwink <charlesbour@gmail.com>
Co-authored-by: Anselmo Sampietro <ans.samp@gmail.com>
Co-authored-by: Emerson Coskey <56370779+ecoskey@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Christian Hughes <9044780+ItsDoot@users.noreply.github.com>
# Objective
`ui_stack_system` generates a tree of `StackingContexts` which it then
flattens to get the `UiStack`.
But there's no need to construct a new tree. We can query for nodes with
a global `ZIndex`, add those nodes to the root nodes list and then build
the `UiStack` from a walk of the existing layout tree, ignoring any
branches that have a global `Zindex`.
Fixes#9877
## Solution
Split the `ZIndex` enum into two separate components, `ZIndex` and
`GlobalZIndex`
Query for nodes with a `GlobalZIndex`, add those nodes to the root nodes
list and then build the `UiStack` from a walk of the existing layout
tree, filtering branches by `Without<GlobalZIndex>` so we don't revisit
nodes.
```
cargo run --profile stress-test --features trace_tracy --example many_buttons
```
<img width="672" alt="ui-stack-system-walk-split-enum"
src="https://github.com/bevyengine/bevy/assets/27962798/11e357a5-477f-4804-8ada-c4527c009421">
(Yellow is this PR, red is main)
---
## Changelog
`Zindex`
* The `ZIndex` enum has been split into two separate components `ZIndex`
(which replaces `ZIndex::Local`) and `GlobalZIndex` (which replaces
`ZIndex::Global`). An entity can have both a `ZIndex` and
`GlobalZIndex`, in comparisons `ZIndex` breaks ties if two
`GlobalZIndex` values are equal.
`ui_stack_system`
* Instead of generating a tree of `StackingContexts`, query for nodes
with a `GlobalZIndex`, add those nodes to the root nodes list and then
build the `UiStack` from a walk of the existing layout tree, filtering
branches by `Without<GlobalZIndex` so we don't revisit nodes.
## Migration Guide
The `ZIndex` enum has been split into two separate components `ZIndex`
(which replaces `ZIndex::Local`) and `GlobalZIndex` (which replaces
`ZIndex::Global`). An entity can have both a `ZIndex` and
`GlobalZIndex`, in comparisons `ZIndex` breaks ties if two
`GlobalZindex` values are equal.
---------
Co-authored-by: Gabriel Bourgeois <gabriel.bourgeoisv4si@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: UkoeHB <37489173+UkoeHB@users.noreply.github.com>
# Objective
- fixes https://github.com/bevyengine/bevy/issues/13473
## Solution
- When a single mesh is assigned multiple materials, it is divided into
several primitive nodes, with each primitive assigned a unique material.
Presently, these primitives are named using the format Mesh.index, which
complicates querying. To improve this, we can assign a specific name to
each primitive based on the material’s name, since each primitive
corresponds to one material exclusively.
## Testing
- I have included a simple example which shows how to query a material
and mesh part based on the new name component.
## Changelog
- adds `GltfMaterialName` component to the mesh entity of the gltf
primitive node.
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Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
