# Objective
- Improve rendering performance, particularly by avoiding the large
system commands costs of using the ECS in the way that the render world
does.
## Solution
- Define `EntityHasher` that calculates a hash from the
`Entity.to_bits()` by `i | (i.wrapping_mul(0x517cc1b727220a95) << 32)`.
`0x517cc1b727220a95` is something like `u64::MAX / N` for N that gives a
value close to π and that works well for hashing. Thanks for @SkiFire13
for the suggestion and to @nicopap for alternative suggestions and
discussion. This approach comes from `rustc-hash` (a.k.a. `FxHasher`)
with some tweaks for the case of hashing an `Entity`. `FxHasher` and
`SeaHasher` were also tested but were significantly slower.
- Define `EntityHashMap` type that uses the `EntityHashser`
- Use `EntityHashMap<Entity, T>` for render world entity storage,
including:
- `RenderMaterialInstances` - contains the `AssetId<M>` of the material
associated with the entity. Also for 2D.
- `RenderMeshInstances` - contains mesh transforms, flags and properties
about mesh entities. Also for 2D.
- `SkinIndices` and `MorphIndices` - contains the skin and morph index
for an entity, respectively
- `ExtractedSprites`
- `ExtractedUiNodes`
## Benchmarks
All benchmarks have been conducted on an M1 Max connected to AC power.
The tests are run for 1500 frames. The 1000th frame is captured for
comparison to check for visual regressions. There were none.
### 2D Meshes
`bevymark --benchmark --waves 160 --per-wave 1000 --mode mesh2d`
#### `--ordered-z`
This test spawns the 2D meshes with z incrementing back to front, which
is the ideal arrangement allocation order as it matches the sorted
render order which means lookups have a high cache hit rate.
<img width="1112" alt="Screenshot 2023-09-27 at 07 50 45"
src="https://github.com/bevyengine/bevy/assets/302146/e140bc98-7091-4a3b-8ae1-ab75d16d2ccb">
-39.1% median frame time.
#### Random
This test spawns the 2D meshes with random z. This not only makes the
batching and transparent 2D pass lookups get a lot of cache misses, it
also currently means that the meshes are almost certain to not be
batchable.
<img width="1108" alt="Screenshot 2023-09-27 at 07 51 28"
src="https://github.com/bevyengine/bevy/assets/302146/29c2e813-645a-43ce-982a-55df4bf7d8c4">
-7.2% median frame time.
### 3D Meshes
`many_cubes --benchmark`
<img width="1112" alt="Screenshot 2023-09-27 at 07 51 57"
src="https://github.com/bevyengine/bevy/assets/302146/1a729673-3254-4e2a-9072-55e27c69f0fc">
-7.7% median frame time.
### Sprites
**NOTE: On `main` sprites are using `SparseSet<Entity, T>`!**
`bevymark --benchmark --waves 160 --per-wave 1000 --mode sprite`
#### `--ordered-z`
This test spawns the sprites with z incrementing back to front, which is
the ideal arrangement allocation order as it matches the sorted render
order which means lookups have a high cache hit rate.
<img width="1116" alt="Screenshot 2023-09-27 at 07 52 31"
src="https://github.com/bevyengine/bevy/assets/302146/bc8eab90-e375-4d31-b5cd-f55f6f59ab67">
+13.0% median frame time.
#### Random
This test spawns the sprites with random z. This makes the batching and
transparent 2D pass lookups get a lot of cache misses.
<img width="1109" alt="Screenshot 2023-09-27 at 07 53 01"
src="https://github.com/bevyengine/bevy/assets/302146/22073f5d-99a7-49b0-9584-d3ac3eac3033">
+0.6% median frame time.
### UI
**NOTE: On `main` UI is using `SparseSet<Entity, T>`!**
`many_buttons`
<img width="1111" alt="Screenshot 2023-09-27 at 07 53 26"
src="https://github.com/bevyengine/bevy/assets/302146/66afd56d-cbe4-49e7-8b64-2f28f6043d85">
+15.1% median frame time.
## Alternatives
- Cart originally suggested trying out `SparseSet<Entity, T>` and indeed
that is slightly faster under ideal conditions. However,
`PassHashMap<Entity, T>` has better worst case performance when data is
randomly distributed, rather than in sorted render order, and does not
have the worst case memory usage that `SparseSet`'s dense `Vec<usize>`
that maps from the `Entity` index to sparse index into `Vec<T>`. This
dense `Vec` has to be as large as the largest Entity index used with the
`SparseSet`.
- I also tested `PassHashMap<u32, T>`, intending to use `Entity.index()`
as the key, but this proved to sometimes be slower and mostly no
different.
- The only outstanding approach that has not been implemented and tested
is to _not_ clear the render world of its entities each frame. That has
its own problems, though they could perhaps be solved.
- Performance-wise, if the entities and their component data were not
cleared, then they would incur table moves on spawn, and should not
thereafter, rather just their component data would be overwritten.
Ideally we would have a neat way of either updating data in-place via
`&mut T` queries, or inserting components if not present. This would
likely be quite cumbersome to have to remember to do everywhere, but
perhaps it only needs to be done in the more performance-sensitive
systems.
- The main problem to solve however is that we want to both maintain a
mapping between main world entities and render world entities, be able
to run the render app and world in parallel with the main app and world
for pipelined rendering, and at the same time be able to spawn entities
in the render world in such a way that those Entity ids do not collide
with those spawned in the main world. This is potentially quite
solvable, but could well be a lot of ECS work to do it in a way that
makes sense.
---
## Changelog
- Changed: Component data for entities to be drawn are no longer stored
on entities in the render world. Instead, data is stored in a
`EntityHashMap<Entity, T>` in various resources. This brings significant
performance benefits due to the way the render app clears entities every
frame. Resources of most interest are `RenderMeshInstances` and
`RenderMaterialInstances`, and their 2D counterparts.
## Migration Guide
Previously the render app extracted mesh entities and their component
data from the main world and stored them as entities and components in
the render world. Now they are extracted into essentially
`EntityHashMap<Entity, T>` where `T` are structs containing an
appropriate group of data. This means that while extract set systems
will continue to run extract queries against the main world they will
store their data in hash maps. Also, systems in later sets will either
need to look up entities in the available resources such as
`RenderMeshInstances`, or maintain their own `EntityHashMap<Entity, T>`
for their own data.
Before:
```rust
fn queue_custom(
material_meshes: Query<(Entity, &MeshTransforms, &Handle<Mesh>), With<InstanceMaterialData>>,
) {
...
for (entity, mesh_transforms, mesh_handle) in &material_meshes {
...
}
}
```
After:
```rust
fn queue_custom(
render_mesh_instances: Res<RenderMeshInstances>,
instance_entities: Query<Entity, With<InstanceMaterialData>>,
) {
...
for entity in &instance_entities {
let Some(mesh_instance) = render_mesh_instances.get(&entity) else { continue; };
// The mesh handle in `AssetId<Mesh>` form, and the `MeshTransforms` can now
// be found in `mesh_instance` which is a `RenderMeshInstance`
...
}
}
```
---------
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
# Objective
The scetion for guides about flexbox has a link to grid and the section
for grid has a link to a guide about flexbox.
## Solution
Swapped links for flexbox and grid.
---
# Objective
Some beginners spend time trying to manually set the position of a
`TextBundle`, without realizing that `Text2dBundle` exists.
## Solution
Mention `Text2dBundle` in the documentation of `TextBundle`.
---------
Co-authored-by: Rob Parrett <robparrett@gmail.com>
derive `Reflect` to `GlyphAtlasInfo`,`PositionedGlyph` and
`TextLayoutInfo`.
# Objective
- I need reflection gets all components of the `TextBundle` and
`clone_value` it
## Solution
- registry it
# Objective
- Implement the foundations of automatic batching/instancing of draw
commands as the next step from #89
- NOTE: More performance improvements will come when more data is
managed and bound in ways that do not require rebinding such as mesh,
material, and texture data.
## Solution
- The core idea for batching of draw commands is to check whether any of
the information that has to be passed when encoding a draw command
changes between two things that are being drawn according to the sorted
render phase order. These should be things like the pipeline, bind
groups and their dynamic offsets, index/vertex buffers, and so on.
- The following assumptions have been made:
- Only entities with prepared assets (pipelines, materials, meshes) are
queued to phases
- View bindings are constant across a phase for a given draw function as
phases are per-view
- `batch_and_prepare_render_phase` is the only system that performs this
batching and has sole responsibility for preparing the per-object data.
As such the mesh binding and dynamic offsets are assumed to only vary as
a result of the `batch_and_prepare_render_phase` system, e.g. due to
having to split data across separate uniform bindings within the same
buffer due to the maximum uniform buffer binding size.
- Implement `GpuArrayBuffer` for `Mesh2dUniform` to store Mesh2dUniform
in arrays in GPU buffers rather than each one being at a dynamic offset
in a uniform buffer. This is the same optimisation that was made for 3D
not long ago.
- Change batch size for a range in `PhaseItem`, adding API for getting
or mutating the range. This is more flexible than a size as the length
of the range can be used in place of the size, but the start and end can
be otherwise whatever is needed.
- Add an optional mesh bind group dynamic offset to `PhaseItem`. This
avoids having to do a massive table move just to insert
`GpuArrayBufferIndex` components.
## Benchmarks
All tests have been run on an M1 Max on AC power. `bevymark` and
`many_cubes` were modified to use 1920x1080 with a scale factor of 1. I
run a script that runs a separate Tracy capture process, and then runs
the bevy example with `--features bevy_ci_testing,trace_tracy` and
`CI_TESTING_CONFIG=../benchmark.ron` with the contents of
`../benchmark.ron`:
```rust
(
exit_after: Some(1500)
)
```
...in order to run each test for 1500 frames.
The recent changes to `many_cubes` and `bevymark` added reproducible
random number generation so that with the same settings, the same rng
will occur. They also added benchmark modes that use a fixed delta time
for animations. Combined this means that the same frames should be
rendered both on main and on the branch.
The graphs compare main (yellow) to this PR (red).
### 3D Mesh `many_cubes --benchmark`
<img width="1411" alt="Screenshot 2023-09-03 at 23 42 10"
src="https://github.com/bevyengine/bevy/assets/302146/2088716a-c918-486c-8129-090b26fd2bc4">
The mesh and material are the same for all instances. This is basically
the best case for the initial batching implementation as it results in 1
draw for the ~11.7k visible meshes. It gives a ~30% reduction in median
frame time.
The 1000th frame is identical using the flip tool:
```
Mean: 0.000000
Weighted median: 0.000000
1st weighted quartile: 0.000000
3rd weighted quartile: 0.000000
Min: 0.000000
Max: 0.000000
Evaluation time: 0.4615 seconds
```
### 3D Mesh `many_cubes --benchmark --material-texture-count 10`
<img width="1404" alt="Screenshot 2023-09-03 at 23 45 18"
src="https://github.com/bevyengine/bevy/assets/302146/5ee9c447-5bd2-45c6-9706-ac5ff8916daf">
This run uses 10 different materials by varying their textures. The
materials are randomly selected, and there is no sorting by material
bind group for opaque 3D so any batching is 'random'. The PR produces a
~5% reduction in median frame time. If we were to sort the opaque phase
by the material bind group, then this should be a lot faster. This
produces about 10.5k draws for the 11.7k visible entities. This makes
sense as randomly selecting from 10 materials gives a chance that two
adjacent entities randomly select the same material and can be batched.
The 1000th frame is identical in flip:
```
Mean: 0.000000
Weighted median: 0.000000
1st weighted quartile: 0.000000
3rd weighted quartile: 0.000000
Min: 0.000000
Max: 0.000000
Evaluation time: 0.4537 seconds
```
### 3D Mesh `many_cubes --benchmark --vary-per-instance`
<img width="1394" alt="Screenshot 2023-09-03 at 23 48 44"
src="https://github.com/bevyengine/bevy/assets/302146/f02a816b-a444-4c18-a96a-63b5436f3b7f">
This run varies the material data per instance by randomly-generating
its colour. This is the worst case for batching and that it performs
about the same as `main` is a good thing as it demonstrates that the
batching has minimal overhead when dealing with ~11k visible mesh
entities.
The 1000th frame is identical according to flip:
```
Mean: 0.000000
Weighted median: 0.000000
1st weighted quartile: 0.000000
3rd weighted quartile: 0.000000
Min: 0.000000
Max: 0.000000
Evaluation time: 0.4568 seconds
```
### 2D Mesh `bevymark --benchmark --waves 160 --per-wave 1000 --mode
mesh2d`
<img width="1412" alt="Screenshot 2023-09-03 at 23 59 56"
src="https://github.com/bevyengine/bevy/assets/302146/cb02ae07-237b-4646-ae9f-fda4dafcbad4">
This spawns 160 waves of 1000 quad meshes that are shaded with
ColorMaterial. Each wave has a different material so 160 waves currently
should result in 160 batches. This results in a 50% reduction in median
frame time.
Capturing a screenshot of the 1000th frame main vs PR gives:
```
Mean: 0.001222
Weighted median: 0.750432
1st weighted quartile: 0.453494
3rd weighted quartile: 0.969758
Min: 0.000000
Max: 0.990296
Evaluation time: 0.4255 seconds
```
So they seem to produce the same results. I also double-checked the
number of draws. `main` does 160000 draws, and the PR does 160, as
expected.
### 2D Mesh `bevymark --benchmark --waves 160 --per-wave 1000 --mode
mesh2d --material-texture-count 10`
<img width="1392" alt="Screenshot 2023-09-04 at 00 09 22"
src="https://github.com/bevyengine/bevy/assets/302146/4358da2e-ce32-4134-82df-3ab74c40849c">
This generates 10 textures and generates materials for each of those and
then selects one material per wave. The median frame time is reduced by
50%. Similar to the plain run above, this produces 160 draws on the PR
and 160000 on `main` and the 1000th frame is identical (ignoring the fps
counter text overlay).
```
Mean: 0.002877
Weighted median: 0.964980
1st weighted quartile: 0.668871
3rd weighted quartile: 0.982749
Min: 0.000000
Max: 0.992377
Evaluation time: 0.4301 seconds
```
### 2D Mesh `bevymark --benchmark --waves 160 --per-wave 1000 --mode
mesh2d --vary-per-instance`
<img width="1396" alt="Screenshot 2023-09-04 at 00 13 53"
src="https://github.com/bevyengine/bevy/assets/302146/b2198b18-3439-47ad-919a-cdabe190facb">
This creates unique materials per instance by randomly-generating the
material's colour. This is the worst case for 2D batching. Somehow, this
PR manages a 7% reduction in median frame time. Both main and this PR
issue 160000 draws.
The 1000th frame is the same:
```
Mean: 0.001214
Weighted median: 0.937499
1st weighted quartile: 0.635467
3rd weighted quartile: 0.979085
Min: 0.000000
Max: 0.988971
Evaluation time: 0.4462 seconds
```
### 2D Sprite `bevymark --benchmark --waves 160 --per-wave 1000 --mode
sprite`
<img width="1396" alt="Screenshot 2023-09-04 at 12 21 12"
src="https://github.com/bevyengine/bevy/assets/302146/8b31e915-d6be-4cac-abf5-c6a4da9c3d43">
This just spawns 160 waves of 1000 sprites. There should be and is no
notable difference between main and the PR.
### 2D Sprite `bevymark --benchmark --waves 160 --per-wave 1000 --mode
sprite --material-texture-count 10`
<img width="1389" alt="Screenshot 2023-09-04 at 12 36 08"
src="https://github.com/bevyengine/bevy/assets/302146/45fe8d6d-c901-4062-a349-3693dd044413">
This spawns the sprites selecting a texture at random per instance from
the 10 generated textures. This has no significant change vs main and
shouldn't.
### 2D Sprite `bevymark --benchmark --waves 160 --per-wave 1000 --mode
sprite --vary-per-instance`
<img width="1401" alt="Screenshot 2023-09-04 at 12 29 52"
src="https://github.com/bevyengine/bevy/assets/302146/762c5c60-352e-471f-8dbe-bbf10e24ebd6">
This sets the sprite colour as being unique per instance. This can still
all be drawn using one batch. There should be no difference but the PR
produces median frame times that are 4% higher. Investigation showed no
clear sources of cost, rather a mix of give and take that should not
happen. It seems like noise in the results.
### Summary
| Benchmark | % change in median frame time |
| ------------- | ------------- |
| many_cubes | 🟩 -30% |
| many_cubes 10 materials | 🟩 -5% |
| many_cubes unique materials | 🟩 ~0% |
| bevymark mesh2d | 🟩 -50% |
| bevymark mesh2d 10 materials | 🟩 -50% |
| bevymark mesh2d unique materials | 🟩 -7% |
| bevymark sprite | 🟥 2% |
| bevymark sprite 10 materials | 🟥 0.6% |
| bevymark sprite unique materials | 🟥 4.1% |
---
## Changelog
- Added: 2D and 3D mesh entities that share the same mesh and material
(same textures, same data) are now batched into the same draw command
for better performance.
---------
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Nicola Papale <nico@nicopap.ch>
# Objective
- When adding/removing bindings in large binding lists, git would
generate very difficult-to-read diffs
## Solution
- Move the `@group(X) @binding(Y)` into the same line as the binding
type declaration
# Objective
Make `bevy_ui` "root" nodes more intuitive to use/style by:
- Removing the implicit flexbox styling (such as stretch alignment) that
is applied to them, and replacing it with more intuitive CSS Grid
styling (notably with stretch alignment disabled in both axes).
- Making root nodes layout independently of each other. Instead of there
being a single implicit "viewport" node that all root nodes are children
of, there is now an implicit "viewport" node *per root node*. And layout
of each tree is computed separately.
## Solution
- Remove the global implicit viewport node, and instead create an
implicit viewport node for each user-specified root node.
- Keep track of both the user-specified root nodes and the implicit
viewport nodes in a separate `Vec`.
- Use the window's size as the `available_space` parameter to
`Taffy.compute_layout` rather than setting it on the implicit viewport
node (and set the viewport to `height: 100%; width: 100%` to make this
"just work").
---
## Changelog
- Bevy UI now lays out root nodes independently of each other in
separate layout contexts.
- The implicit viewport node (which contains each user-specified root
node) is now `Display::Grid` with `align_items` and `justify_items` both
set to `Start`.
## Migration Guide
- Bevy UI now lays out root nodes independently of each other in
separate layout contexts. If you were relying on your root nodes being
able to affect each other's layouts, then you may need to wrap them in a
single root node.
- The implicit viewport node (which contains each user-specified root
node) is now `Display::Grid` with `align_items` and `justify_items` both
set to `Start`. You may need to add `height: Val::Percent(100.)` to your
root nodes if you were previously relying on being implicitly set.
# Objective
Replace instances of
```rust
for x in collection.iter{_mut}() {
```
with
```rust
for x in &{mut} collection {
```
This also changes CI to no longer suppress this lint. Note that since
this lint only shows up when using clippy in pedantic mode, it was
probably unnecessary to suppress this lint in the first place.
# Objective
If you remove a `ContentSize` component from a Bevy UI entity and then
replace it `ui_layout_system` will remove the measure func from the
internal Taffy layout tree but no new measure func will be generated to
replace it since it's the widget systems that are responsible for
creating their respective measure funcs not `ui_layout_system`. The
widget systems only perform a measure func update on changes to a widget
entity's content. This means that until its content is changed in some
way, no content will be displayed by the node.
### Example
This example spawns a text node which disappears after a few moments
once its `ContentSize` component is replaced.
```rust
use bevy::prelude::*;
use bevy::ui::ContentSize;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, delayed_replacement)
.run();
}
fn setup(mut commands: Commands) {
commands.spawn(Camera2dBundle::default());
commands.spawn(
TextBundle::from_section(
"Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.",
TextStyle::default(),
)
);
}
// Waits a few frames to make sure the font is loaded and the text's glyph layout has been generated.
fn delayed_replacement(mut commands: Commands, mut count: Local<usize>, query: Query<Entity, With<Style>>) {
*count += 1;
if *count == 10 {
for item in query.iter() {
commands
.entity(item)
.remove::<ContentSize>()
.insert(ContentSize::default());
}
}
}
```
## Solution
Perform `ui_layout_system`'s `ContentSize` removal detection and
resolution first, before the measure func updates.
Then in the widget systems, generate a new `Measure` when a
`ContentSize` component is added to a widget entity.
## Changelog
* `measure_text_system`, `update_image_content_size_system` and
`update_atlas_content_size_system` generate a new `Measure` when a
`ContentSize` component is added.
# Objective
`Val`'s natural place is in the `geometry` module with `UiRect`, not in
`ui_node` with the components.
## Solution
Move `Val` into `geometry`.
# Objective
Rename RemovedComponents::iter/iter_with_id to read/read_with_id to make
it clear that it consume the data
Fixes#9755.
(It's my first pull request, if i've made any mistake, please let me
know)
## Solution
Refactor RemovedComponents::iter/iter_with_id to read/read_with_id
## Changelog
Refactor RemovedComponents::iter/iter_with_id to read/read_with_id
Deprecate RemovedComponents::iter/iter_with_id
Remove IntoIterator implementation
Update removal_detection example accordingly
---
## Migration Guide
Rename calls of RemovedComponents::iter/iter_with_id to
read/read_with_id
Replace IntoIterator iteration (&mut <RemovedComponents>) with .read()
---------
Co-authored-by: denshi_ika <mojang2824@gmail.com>
# Objective
Add tests for `ui_layout_system` and `UiSurface` to the
`bevy_ui::Layout` module.
## Solution
Spawn a dummy window entity with `Window` and `PrimaryWindow` components
so that `ui_layout_system` can run in a test without a window present.
---
## Changelog
Added tests to the `bevy_ui::layout` module.
# Objective
Implement `From<String>` and `From<&str>` for `TextSection`
Example from something I was working on earlier:
```rust
parent.spawn(TextBundle::from_sections([
TextSection::new("press ".to_string(), TextStyle::default()),
TextSection::new("space".to_string(), TextStyle { color: Color::YELLOW, ..default() }),
TextSection::new(" to advance frames".to_string(), TextStyle::default()),
]));
```
After an `impl From<&str> for TextSection` :
```rust
parent.spawn(TextBundle::from_sections([
"press ".into(),
TextSection::new("space".to_string(), TextStyle { color: Color::YELLOW, ..default() }),
" to advance frames".into(),
]));
```
* Potentially unhelpful without a default font, so behind the
`default_font` feature.
Co-authored-by: [hate](https://github.com/hate)
---------
Co-authored-by: hate <15314665+hate@users.noreply.github.com>
# Objective
`TextLayoutInfo::size` isn't the drawn size of the text, but a scaled
value. This is fragile, counter-intuitive and makes it awkward to
retrieve the correct value.
## Solution
Multiply `TextLayoutInfo::size` by the reciprocal of the window's scale
factor after generating the text layout in `update_text2d_layout` and
`bevy_ui::widget::text_system`.
---
fixes: #7787
## Changelog
* Multiply `TextLayoutInfo::size` by the reciprocal of the scale factor
after text computation to reflect the actual size of the text as drawn.
* Reorder the operations in `extract_text2d_sprite` to apply the
alignment offset before the scale factor scaling.
## Migration Guide
The `size` value of `TextLayoutInfo` is stored in logical pixels and has
been renamed to `logical_size`. There is no longer any need to divide by
the window's scale factor to get the logical size.
# Bevy Asset V2 Proposal
## Why Does Bevy Need A New Asset System?
Asset pipelines are a central part of the gamedev process. Bevy's
current asset system is missing a number of features that make it
non-viable for many classes of gamedev. After plenty of discussions and
[a long community feedback
period](https://github.com/bevyengine/bevy/discussions/3972), we've
identified a number missing features:
* **Asset Preprocessing**: it should be possible to "preprocess" /
"compile" / "crunch" assets at "development time" rather than when the
game starts up. This enables offloading expensive work from deployed
apps, faster asset loading, less runtime memory usage, etc.
* **Per-Asset Loader Settings**: Individual assets cannot define their
own loaders that override the defaults. Additionally, they cannot
provide per-asset settings to their loaders. This is a huge limitation,
as many asset types don't provide all information necessary for Bevy
_inside_ the asset. For example, a raw PNG image says nothing about how
it should be sampled (ex: linear vs nearest).
* **Asset `.meta` files**: assets should have configuration files stored
adjacent to the asset in question, which allows the user to configure
asset-type-specific settings. These settings should be accessible during
the pre-processing phase. Modifying a `.meta` file should trigger a
re-processing / re-load of the asset. It should be possible to configure
asset loaders from the meta file.
* **Processed Asset Hot Reloading**: Changes to processed assets (or
their dependencies) should result in re-processing them and re-loading
the results in live Bevy Apps.
* **Asset Dependency Tracking**: The current bevy_asset has no good way
to wait for asset dependencies to load. It punts this as an exercise for
consumers of the loader apis, which is unreasonable and error prone.
There should be easy, ergonomic ways to wait for assets to load and
block some logic on an asset's entire dependency tree loading.
* **Runtime Asset Loading**: it should be (optionally) possible to load
arbitrary assets dynamically at runtime. This necessitates being able to
deploy and run the asset server alongside Bevy Apps on _all platforms_.
For example, we should be able to invoke the shader compiler at runtime,
stream scenes from sources like the internet, etc. To keep deployed
binaries (and startup times) small, the runtime asset server
configuration should be configurable with different settings compared to
the "pre processor asset server".
* **Multiple Backends**: It should be possible to load assets from
arbitrary sources (filesystems, the internet, remote asset serves, etc).
* **Asset Packing**: It should be possible to deploy assets in
compressed "packs", which makes it easier and more efficient to
distribute assets with Bevy Apps.
* **Asset Handoff**: It should be possible to hold a "live" asset
handle, which correlates to runtime data, without actually holding the
asset in memory. Ex: it must be possible to hold a reference to a GPU
mesh generated from a "mesh asset" without keeping the mesh data in CPU
memory
* **Per-Platform Processed Assets**: Different platforms and app
distributions have different capabilities and requirements. Some
platforms need lower asset resolutions or different asset formats to
operate within the hardware constraints of the platform. It should be
possible to define per-platform asset processing profiles. And it should
be possible to deploy only the assets required for a given platform.
These features have architectural implications that are significant
enough to require a full rewrite. The current Bevy Asset implementation
got us this far, but it can take us no farther. This PR defines a brand
new asset system that implements most of these features, while laying
the foundations for the remaining features to be built.
## Bevy Asset V2
Here is a quick overview of the features introduced in this PR.
* **Asset Preprocessing**: Preprocess assets at development time into
more efficient (and configurable) representations
* **Dependency Aware**: Dependencies required to process an asset are
tracked. If an asset's processed dependency changes, it will be
reprocessed
* **Hot Reprocessing/Reloading**: detect changes to asset source files,
reprocess them if they have changed, and then hot-reload them in Bevy
Apps.
* **Only Process Changes**: Assets are only re-processed when their
source file (or meta file) has changed. This uses hashing and timestamps
to avoid processing assets that haven't changed.
* **Transactional and Reliable**: Uses write-ahead logging (a technique
commonly used by databases) to recover from crashes / forced-exits.
Whenever possible it avoids full-reprocessing / only uncompleted
transactions will be reprocessed. When the processor is running in
parallel with a Bevy App, processor asset writes block Bevy App asset
reads. Reading metadata + asset bytes is guaranteed to be transactional
/ correctly paired.
* **Portable / Run anywhere / Database-free**: The processor does not
rely on an in-memory database (although it uses some database techniques
for reliability). This is important because pretty much all in-memory
databases have unsupported platforms or build complications.
* **Configure Processor Defaults Per File Type**: You can say "use this
processor for all files of this type".
* **Custom Processors**: The `Processor` trait is flexible and
unopinionated. It can be implemented by downstream plugins.
* **LoadAndSave Processors**: Most asset processing scenarios can be
expressed as "run AssetLoader A, save the results using AssetSaver X,
and then load the result using AssetLoader B". For example, load this
png image using `PngImageLoader`, which produces an `Image` asset and
then save it using `CompressedImageSaver` (which also produces an
`Image` asset, but in a compressed format), which takes an `Image` asset
as input. This means if you have an `AssetLoader` for an asset, you are
already half way there! It also means that you can share AssetSavers
across multiple loaders. Because `CompressedImageSaver` accepts Bevy's
generic Image asset as input, it means you can also use it with some
future `JpegImageLoader`.
* **Loader and Saver Settings**: Asset Loaders and Savers can now define
their own settings types, which are passed in as input when an asset is
loaded / saved. Each asset can define its own settings.
* **Asset `.meta` files**: configure asset loaders, their settings,
enable/disable processing, and configure processor settings
* **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex:
if an asset contains a `Handle<Image>`) are tracked by the asset server.
An event is emitted when an asset and all of its dependencies have been
loaded
* **Unprocessed Asset Loading**: Assets do not require preprocessing.
They can be loaded directly. A processed asset is just a "normal" asset
with some extra metadata. Asset Loaders don't need to know or care about
whether or not an asset was processed.
* **Async Asset IO**: Asset readers/writers use async non-blocking
interfaces. Note that because Rust doesn't yet support async traits,
there is a bit of manual Boxing / Future boilerplate. This will
hopefully be removed in the near future when Rust gets async traits.
* **Pluggable Asset Readers and Writers**: Arbitrary asset source
readers/writers are supported, both by the processor and the asset
server.
* **Better Asset Handles**
* **Single Arc Tree**: Asset Handles now use a single arc tree that
represents the lifetime of the asset. This makes their implementation
simpler, more efficient, and allows us to cheaply attach metadata to
handles. Ex: the AssetPath of a handle is now directly accessible on the
handle itself!
* **Const Typed Handles**: typed handles can be constructed in a const
context. No more weird "const untyped converted to typed at runtime"
patterns!
* **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed
`Handle<T>` is now much smaller in memory and `AssetId<T>` is even
smaller.
* **Weak Handle Usage Reduction**: In general Handles are now considered
to be "strong". Bevy features that previously used "weak `Handle<T>`"
have been ported to `AssetId<T>`, which makes it statically clear that
the features do not hold strong handles (while retaining strong type
information). Currently Handle::Weak still exists, but it is very
possible that we can remove that entirely.
* **Efficient / Dense Asset Ids**: Assets now have efficient dense
runtime asset ids, which means we can avoid expensive hash lookups.
Assets are stored in Vecs instead of HashMaps. There are now typed and
untyped ids, which means we no longer need to store dynamic type
information in the ID for typed handles. "AssetPathId" (which was a
nightmare from a performance and correctness standpoint) has been
entirely removed in favor of dense ids (which are retrieved for a path
on load)
* **Direct Asset Loading, with Dependency Tracking**: Assets that are
defined at runtime can still have their dependencies tracked by the
Asset Server (ex: if you create a material at runtime, you can still
wait for its textures to load). This is accomplished via the (currently
optional) "asset dependency visitor" trait. This system can also be used
to define a set of assets to load, then wait for those assets to load.
* **Async folder loading**: Folder loading also uses this system and
immediately returns a handle to the LoadedFolder asset, which means
folder loading no longer blocks on directory traversals.
* **Improved Loader Interface**: Loaders now have a specific "top level
asset type", which makes returning the top-level asset simpler and
statically typed.
* **Basic Image Settings and Processing**: Image assets can now be
processed into the gpu-friendly Basic Universal format. The ImageLoader
now has a setting to define what format the image should be loaded as.
Note that this is just a minimal MVP ... plenty of additional work to do
here. To demo this, enable the `basis-universal` feature and turn on
asset processing.
* **Simpler Audio Play / AudioSink API**: Asset handle providers are
cloneable, which means the Audio resource can mint its own handles. This
means you can now do `let sink_handle = audio.play(music)` instead of
`let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that
this might still be replaced by
https://github.com/bevyengine/bevy/pull/8424.
**Removed Handle Casting From Engine Features**: Ex: FontAtlases no
longer use casting between handle types
## Using The New Asset System
### Normal Unprocessed Asset Loading
By default the `AssetPlugin` does not use processing. It behaves pretty
much the same way as the old system.
If you are defining a custom asset, first derive `Asset`:
```rust
#[derive(Asset)]
struct Thing {
value: String,
}
```
Initialize the asset:
```rust
app.init_asset:<Thing>()
```
Implement a new `AssetLoader` for it:
```rust
#[derive(Default)]
struct ThingLoader;
#[derive(Serialize, Deserialize, Default)]
pub struct ThingSettings {
some_setting: bool,
}
impl AssetLoader for ThingLoader {
type Asset = Thing;
type Settings = ThingSettings;
fn load<'a>(
&'a self,
reader: &'a mut Reader,
settings: &'a ThingSettings,
load_context: &'a mut LoadContext,
) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> {
Box::pin(async move {
let mut bytes = Vec::new();
reader.read_to_end(&mut bytes).await?;
// convert bytes to value somehow
Ok(Thing {
value
})
})
}
fn extensions(&self) -> &[&str] {
&["thing"]
}
}
```
Note that this interface will get much cleaner once Rust gets support
for async traits. `Reader` is an async futures_io::AsyncRead. You can
stream bytes as they come in or read them all into a `Vec<u8>`,
depending on the context. You can use `let handle =
load_context.load(path)` to kick off a dependency load, retrieve a
handle, and register the dependency for the asset.
Then just register the loader in your Bevy app:
```rust
app.init_asset_loader::<ThingLoader>()
```
Now just add your `Thing` asset files into the `assets` folder and load
them like this:
```rust
fn system(asset_server: Res<AssetServer>) {
let handle = Handle<Thing> = asset_server.load("cool.thing");
}
```
You can check load states directly via the asset server:
```rust
if asset_server.load_state(&handle) == LoadState::Loaded { }
```
You can also listen for events:
```rust
fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) {
for event in events.iter() {
if event.is_loaded_with_dependencies(&handle) {
}
}
}
```
Note the new `AssetEvent::LoadedWithDependencies`, which only fires when
the asset is loaded _and_ all dependencies (and their dependencies) have
loaded.
Unlike the old asset system, for a given asset path all `Handle<T>`
values point to the same underlying Arc. This means Handles can cheaply
hold more asset information, such as the AssetPath:
```rust
// prints the AssetPath of the handle
info!("{:?}", handle.path())
```
### Processed Assets
Asset processing can be enabled via the `AssetPlugin`. When developing
Bevy Apps with processed assets, do this:
```rust
app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))
```
This runs the `AssetProcessor` in the background with hot-reloading. It
reads assets from the `assets` folder, processes them, and writes them
to the `.imported_assets` folder. Asset loads in the Bevy App will wait
for a processed version of the asset to become available. If an asset in
the `assets` folder changes, it will be reprocessed and hot-reloaded in
the Bevy App.
When deploying processed Bevy apps, do this:
```rust
app.add_plugins(DefaultPlugins.set(AssetPlugin::processed()))
```
This does not run the `AssetProcessor` in the background. It behaves
like `AssetPlugin::unprocessed()`, but reads assets from
`.imported_assets`.
When the `AssetProcessor` is running, it will populate sibling `.meta`
files for assets in the `assets` folder. Meta files for assets that do
not have a processor configured look like this:
```rust
(
meta_format_version: "1.0",
asset: Load(
loader: "bevy_render::texture::image_loader::ImageLoader",
settings: (
format: FromExtension,
),
),
)
```
This is metadata for an image asset. For example, if you have
`assets/my_sprite.png`, this could be the metadata stored at
`assets/my_sprite.png.meta`. Meta files are totally optional. If no
metadata exists, the default settings will be used.
In short, this file says "load this asset with the ImageLoader and use
the file extension to determine the image type". This type of meta file
is supported in all AssetPlugin modes. If in `Unprocessed` mode, the
asset (with the meta settings) will be loaded directly. If in
`ProcessedDev` mode, the asset file will be copied directly to the
`.imported_assets` folder. The meta will also be copied directly to the
`.imported_assets` folder, but with one addition:
```rust
(
meta_format_version: "1.0",
processed_info: Some((
hash: 12415480888597742505,
full_hash: 14344495437905856884,
process_dependencies: [],
)),
asset: Load(
loader: "bevy_render::texture::image_loader::ImageLoader",
settings: (
format: FromExtension,
),
),
)
```
`processed_info` contains `hash` (a direct hash of the asset and meta
bytes), `full_hash` (a hash of `hash` and the hashes of all
`process_dependencies`), and `process_dependencies` (the `path` and
`full_hash` of every process_dependency). A "process dependency" is an
asset dependency that is _directly_ used when processing the asset.
Images do not have process dependencies, so this is empty.
When the processor is enabled, you can use the `Process` metadata
config:
```rust
(
meta_format_version: "1.0",
asset: Process(
processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>",
settings: (
loader_settings: (
format: FromExtension,
),
saver_settings: (
generate_mipmaps: true,
),
),
),
)
```
This configures the asset to use the `LoadAndSave` processor, which runs
an AssetLoader and feeds the result into an AssetSaver (which saves the
given Asset and defines a loader to load it with). (for terseness
LoadAndSave will likely get a shorter/friendlier type name when [Stable
Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common
processor type, but arbitrary processors are supported.
`CompressedImageSaver` saves an `Image` in the Basis Universal format
and configures the ImageLoader to load it as basis universal. The
`AssetProcessor` will read this meta, run it through the LoadAndSave
processor, and write the basis-universal version of the image to
`.imported_assets`. The final metadata will look like this:
```rust
(
meta_format_version: "1.0",
processed_info: Some((
hash: 905599590923828066,
full_hash: 9948823010183819117,
process_dependencies: [],
)),
asset: Load(
loader: "bevy_render::texture::image_loader::ImageLoader",
settings: (
format: Format(Basis),
),
),
)
```
To try basis-universal processing out in Bevy examples, (for example
`sprite.rs`), change `add_plugins(DefaultPlugins)` to
`add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run
with the `basis-universal` feature enabled: `cargo run
--features=basis-universal --example sprite`.
To create a custom processor, there are two main paths:
1. Use the `LoadAndSave` processor with an existing `AssetLoader`.
Implement the `AssetSaver` trait, register the processor using
`asset_processor.register_processor::<LoadAndSave<ImageLoader,
CompressedImageSaver>>(image_saver.into())`.
2. Implement the `Process` trait directly and register it using:
`asset_processor.register_processor(thing_processor)`.
You can configure default processors for file extensions like this:
```rust
asset_processor.set_default_processor::<ThingProcessor>("thing")
```
There is one more metadata type to be aware of:
```rust
(
meta_format_version: "1.0",
asset: Ignore,
)
```
This will ignore the asset during processing / prevent it from being
written to `.imported_assets`.
The AssetProcessor stores a transaction log at `.imported_assets/log`
and uses it to gracefully recover from unexpected stops. This means you
can force-quit the processor (and Bevy Apps running the processor in
parallel) at arbitrary times!
`.imported_assets` is "local state". It should _not_ be checked into
source control. It should also be considered "read only". In practice,
you _can_ modify processed assets and processed metadata if you really
need to test something. But those modifications will not be represented
in the hashes of the assets, so the processed state will be "out of
sync" with the source assets. The processor _will not_ fix this for you.
Either revert the change after you have tested it, or delete the
processed files so they can be re-populated.
## Open Questions
There are a number of open questions to be discussed. We should decide
if they need to be addressed in this PR and if so, how we will address
them:
### Implied Dependencies vs Dependency Enumeration
There are currently two ways to populate asset dependencies:
* **Implied via AssetLoaders**: if an AssetLoader loads an asset (and
retrieves a handle), a dependency is added to the list.
* **Explicit via the optional Asset::visit_dependencies**: if
`server.load_asset(my_asset)` is called, it will call
`my_asset.visit_dependencies`, which will grab dependencies that have
been manually defined for the asset via the Asset trait impl (which can
be derived).
This means that defining explicit dependencies is optional for "loaded
assets". And the list of dependencies is always accurate because loaders
can only produce Handles if they register dependencies. If an asset was
loaded with an AssetLoader, it only uses the implied dependencies. If an
asset was created at runtime and added with
`asset_server.load_asset(MyAsset)`, it will use
`Asset::visit_dependencies`.
However this can create a behavior mismatch between loaded assets and
equivalent "created at runtime" assets if `Assets::visit_dependencies`
doesn't exactly match the dependencies produced by the AssetLoader. This
behavior mismatch can be resolved by completely removing "implied loader
dependencies" and requiring `Asset::visit_dependencies` to supply
dependency data. But this creates two problems:
* It makes defining loaded assets harder and more error prone: Devs must
remember to manually annotate asset dependencies with `#[dependency]`
when deriving `Asset`. For more complicated assets (such as scenes), the
derive likely wouldn't be sufficient and a manual `visit_dependencies`
impl would be required.
* Removes the ability to immediately kick off dependency loads: When
AssetLoaders retrieve a Handle, they also immediately kick off an asset
load for the handle, which means it can start loading in parallel
_before_ the asset finishes loading. For large assets, this could be
significant. (although this could be mitigated for processed assets if
we store dependencies in the processed meta file and load them ahead of
time)
### Eager ProcessorDev Asset Loading
I made a controversial call in the interest of fast startup times ("time
to first pixel") for the "processor dev mode configuration". When
initializing the AssetProcessor, current processed versions of unchanged
assets are yielded immediately, even if their dependencies haven't been
checked yet for reprocessing. This means that
non-current-state-of-filesystem-but-previously-valid assets might be
returned to the App first, then hot-reloaded if/when their dependencies
change and the asset is reprocessed.
Is this behavior desirable? There is largely one alternative: do not
yield an asset from the processor to the app until all of its
dependencies have been checked for changes. In some common cases (load
dependency has not changed since last run) this will increase startup
time. The main question is "by how much" and is that slower startup time
worth it in the interest of only yielding assets that are true to the
current state of the filesystem. Should this be configurable? I'm
starting to think we should only yield an asset after its (historical)
dependencies have been checked for changes + processed as necessary, but
I'm curious what you all think.
### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs?
In this implementation AssetPaths are the only canonical asset
identifier (just like the previous Bevy Asset system and Godot). Moving
assets will result in re-scans (and currently reprocessing, although
reprocessing can easily be avoided with some changes). Asset
renames/moves will break code and assets that rely on specific paths,
unless those paths are fixed up.
Do we want / need "stable asset uuids"? Introducing them is very
possible:
1. Generate a UUID and include it in .meta files
2. Support UUID in AssetPath
3. Generate "asset indices" which are loaded on startup and map UUIDs to
paths.
4 (maybe). Consider only supporting UUIDs for processed assets so we can
generate quick-to-load indices instead of scanning meta files.
The main "pro" is that assets referencing UUIDs don't need to be
migrated when a path changes. The main "con" is that UUIDs cannot be
"lazily resolved" like paths. They need a full view of all assets to
answer the question "does this UUID exist". Which means UUIDs require
the AssetProcessor to fully finish startup scans before saying an asset
doesnt exist. And they essentially require asset pre-processing to use
in apps, because scanning all asset metadata files at runtime to resolve
a UUID is not viable for medium-to-large apps. It really requires a
pre-generated UUID index, which must be loaded before querying for
assets.
I personally think this should be investigated in a separate PR. Paths
aren't going anywhere ... _everyone_ uses filesystems (and
filesystem-like apis) to manage their asset source files. I consider
them permanent canonical asset information. Additionally, they behave
well for both processed and unprocessed asset modes. Given that Bevy is
supporting both, this feels like the right canonical ID to start with.
UUIDS (and maybe even other indexed-identifier types) can be added later
as necessary.
### Folder / File Naming Conventions
All asset processing config currently lives in the `.imported_assets`
folder. The processor transaction log is in `.imported_assets/log`.
Processed assets are added to `.imported_assets/Default`, which will
make migrating to processed asset profiles (ex: a
`.imported_assets/Mobile` profile) a non-breaking change. It also allows
us to create top-level files like `.imported_assets/log` without it
being interpreted as an asset. Meta files currently have a `.meta`
suffix. Do we like these names and conventions?
### Should the `AssetPlugin::processed_dev` configuration enable
`watch_for_changes` automatically?
Currently it does (which I think makes sense), but it does make it the
only configuration that enables watch_for_changes by default.
### Discuss on_loaded High Level Interface:
This PR includes a very rough "proof of concept" `on_loaded` system
adapter that uses the `LoadedWithDependencies` event in combination with
`asset_server.load_asset` dependency tracking to support this pattern
```rust
fn main() {
App::new()
.init_asset::<MyAssets>()
.add_systems(Update, on_loaded(create_array_texture))
.run();
}
#[derive(Asset, Clone)]
struct MyAssets {
#[dependency]
picture_of_my_cat: Handle<Image>,
#[dependency]
picture_of_my_other_cat: Handle<Image>,
}
impl FromWorld for ArrayTexture {
fn from_world(world: &mut World) -> Self {
picture_of_my_cat: server.load("meow.png"),
picture_of_my_other_cat: server.load("meeeeeeeow.png"),
}
}
fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) {
commands.spawn(SpriteBundle {
texture: my_assets.picture_of_my_cat.clone(),
..default()
});
commands.spawn(SpriteBundle {
texture: my_assets.picture_of_my_other_cat.clone(),
..default()
});
}
```
The implementation is _very_ rough. And it is currently unsafe because
`bevy_ecs` doesn't expose some internals to do this safely from inside
`bevy_asset`. There are plenty of unanswered questions like:
* "do we add a Loadable" derive? (effectively automate the FromWorld
implementation above)
* Should `MyAssets` even be an Asset? (largely implemented this way
because it elegantly builds on `server.load_asset(MyAsset { .. })`
dependency tracking).
We should think hard about what our ideal API looks like (and if this is
a pattern we want to support). Not necessarily something we need to
solve in this PR. The current `on_loaded` impl should probably be
removed from this PR before merging.
## Clarifying Questions
### What about Assets as Entities?
This Bevy Asset V2 proposal implementation initially stored Assets as
ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used
`Entity` as the asset id and Asset values were just ECS components.
There are plenty of compelling reasons to do this:
1. Easier to inline assets in Bevy Scenes (as they are "just" normal
entities + components)
2. More flexible queries: use the power of the ECS to filter assets (ex:
`Query<Mesh, With<Tree>>`).
3. Extensible. Users can add arbitrary component data to assets.
4. Things like "component visualization tools" work out of the box to
visualize asset data.
However Assets as Entities has a ton of caveats right now:
* We need to be able to allocate entity ids without a direct World
reference (aka rework id allocator in Entities ... i worked around this
in my prototypes by just pre allocating big chunks of entities)
* We want asset change events in addition to ECS change tracking ... how
do we populate them when mutations can come from anywhere? Do we use
Changed queries? This would require iterating over the change data for
all assets every frame. Is this acceptable or should we implement a new
"event based" component change detection option?
* Reconciling manually created assets with asset-system managed assets
has some nuance (ex: are they "loaded" / do they also have that
component metadata?)
* "how do we handle "static" / default entity handles" (ties in to the
Entity Indices discussion:
https://github.com/bevyengine/bevy/discussions/8319). This is necessary
for things like "built in" assets and default handles in things like
SpriteBundle.
* Storing asset information as a component makes it easy to "invalidate"
asset state by removing the component (or forcing modifications).
Ideally we have ways to lock this down (some combination of Rust type
privacy and ECS validation)
In practice, how we store and identify assets is a reasonably
superficial change (porting off of Assets as Entities and implementing
dedicated storage + ids took less than a day). So once we sort out the
remaining challenges the flip should be straightforward. Additionally, I
do still have "Assets as Entities" in my commit history, so we can reuse
that work. I personally think "assets as entities" is a good endgame,
but it also doesn't provide _significant_ value at the moment and it
certainly isn't ready yet with the current state of things.
### Why not Distill?
[Distill](https://github.com/amethyst/distill) is a high quality fully
featured asset system built in Rust. It is very natural to ask "why not
just use Distill?".
It is also worth calling out that for awhile, [we planned on adopting
Distill / I signed off on
it](https://github.com/bevyengine/bevy/issues/708).
However I think Bevy has a number of constraints that make Distill
adoption suboptimal:
* **Architectural Simplicity:**
* Distill's processor requires an in-memory database (lmdb) and RPC
networked API (using Cap'n Proto). Each of these introduces API
complexity that increases maintenance burden and "code grokability".
Ignoring tests, documentation, and examples, Distill has 24,237 lines of
Rust code (including generated code for RPC + database interactions). If
you ignore generated code, it has 11,499 lines.
* Bevy builds the AssetProcessor and AssetServer using pluggable
AssetReader/AssetWriter Rust traits with simple io interfaces. They do
not necessitate databases or RPC interfaces (although Readers/Writers
could use them if that is desired). Bevy Asset V2 (at the time of
writing this PR) is 5,384 lines of Rust code (ignoring tests,
documentation, and examples). Grain of salt: Distill does have more
features currently (ex: Asset Packing, GUIDS, remote-out-of-process
asset processor). I do plan to implement these features in Bevy Asset V2
and I personally highly doubt they will meaningfully close the 6115
lines-of-code gap.
* This complexity gap (which while illustrated by lines of code, is much
bigger than just that) is noteworthy to me. Bevy should be hackable and
there are pillars of Distill that are very hard to understand and
extend. This is a matter of opinion (and Bevy Asset V2 also has
complicated areas), but I think Bevy Asset V2 is much more approachable
for the average developer.
* Necessary disclaimer: counting lines of code is an extremely rough
complexity metric. Read the code and form your own opinions.
* **Optional Asset Processing:** Not all Bevy Apps (or Bevy App
developers) need / want asset preprocessing. Processing increases the
complexity of the development environment by introducing things like
meta files, imported asset storage, running processors in the
background, waiting for processing to finish, etc. Distill _requires_
preprocessing to work. With Bevy Asset V2 processing is fully opt-in.
The AssetServer isn't directly aware of asset processors at all.
AssetLoaders only care about converting bytes to runtime Assets ... they
don't know or care if the bytes were pre-processed or not. Processing is
"elegantly" (forgive my self-congratulatory phrasing) layered on top and
builds on the existing Asset system primitives.
* **Direct Filesystem Access to Processed Asset State:** Distill stores
processed assets in a database. This makes debugging / inspecting the
processed outputs harder (either requires special tooling to query the
database or they need to be "deployed" to be inspected). Bevy Asset V2,
on the other hand, stores processed assets in the filesystem (by default
... this is configurable). This makes interacting with the processed
state more natural. Note that both Godot and Unity's new asset system
store processed assets in the filesystem.
* **Portability**: Because Distill's processor uses lmdb and RPC
networking, it cannot be run on certain platforms (ex: lmdb is a
non-rust dependency that cannot run on the web, some platforms don't
support running network servers). Bevy should be able to process assets
everywhere (ex: run the Bevy Editor on the web, compile + process
shaders on mobile, etc). Distill does partially mitigate this problem by
supporting "streaming" assets via the RPC protocol, but this is not a
full solve from my perspective. And Bevy Asset V2 can (in theory) also
stream assets (without requiring RPC, although this isn't implemented
yet)
Note that I _do_ still think Distill would be a solid asset system for
Bevy. But I think the approach in this PR is a better solve for Bevy's
specific "asset system requirements".
### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the
point?
"True async file io" has limited / spotty platform support. async-fs
(and the rust async ecosystem generally ... ex Tokio) currently use
async wrappers over std::fs that offload blocking requests to separate
threads. This may feel unsatisfying, but it _does_ still provide value
because it prevents our task pools from blocking on file system
operations (which would prevent progress when there are many tasks to
do, but all threads in a pool are currently blocking on file system
ops).
Additionally, using async APIs for our AssetReaders and AssetWriters
also provides value because we can later add support for "true async
file io" for platforms that support it. _And_ we can implement other
"true async io" asset backends (such as networked asset io).
## Draft TODO
- [x] Fill in missing filesystem event APIs: file removed event (which
is expressed as dangling RenameFrom events in some cases), file/folder
renamed event
- [x] Assets without loaders are not moved to the processed folder. This
breaks things like referenced `.bin` files for GLTFs. This should be
configurable per-non-asset-type.
- [x] Initial implementation of Reflect and FromReflect for Handle. The
"deserialization" parity bar is low here as this only worked with static
UUIDs in the old impl ... this is a non-trivial problem. Either we add a
Handle::AssetPath variant that gets "upgraded" to a strong handle on
scene load or we use a separate AssetRef type for Bevy scenes (which is
converted to a runtime Handle on load). This deserves its own discussion
in a different pr.
- [x] Populate read_asset_bytes hash when run by the processor (a bit of
a special case .. when run by the processor the processed meta will
contain the hash so we don't need to compute it on the spot, but we
don't want/need to read the meta when run by the main AssetServer)
- [x] Delay hot reloading: currently filesystem events are handled
immediately, which creates timing issues in some cases. For example hot
reloading images can sometimes break because the image isn't finished
writing. We should add a delay, likely similar to the [implementation in
this PR](https://github.com/bevyengine/bevy/pull/8503).
- [x] Port old platform-specific AssetIo implementations to the new
AssetReader interface (currently missing Android and web)
- [x] Resolve on_loaded unsafety (either by removing the API entirely or
removing the unsafe)
- [x] Runtime loader setting overrides
- [x] Remove remaining unwraps that should be error-handled. There are
number of TODOs here
- [x] Pretty AssetPath Display impl
- [x] Document more APIs
- [x] Resolve spurious "reloading because it has changed" events (to
repro run load_gltf with `processed_dev()`)
- [x] load_dependency hot reloading currently only works for processed
assets. If processing is disabled, load_dependency changes are not hot
reloaded.
- [x] Replace AssetInfo dependency load/fail counters with
`loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from
(potentially) breaking counters. Storing this will also enable
"dependency reloaded" events (see [Next Steps](#next-steps))
- [x] Re-add filesystem watcher cargo feature gate (currently it is not
optional)
- [ ] Migration Guide
- [ ] Changelog
## Followup TODO
- [ ] Replace "eager unchanged processed asset loading" behavior with
"don't returned unchanged processed asset until dependencies have been
checked".
- [ ] Add true `Ignore` AssetAction that does not copy the asset to the
imported_assets folder.
- [ ] Finish "live asset unloading" (ex: free up CPU asset memory after
uploading an image to the GPU), rethink RenderAssets, and port renderer
features. The `Assets` collection uses `Option<T>` for asset storage to
support its removal. (1) the Option might not actually be necessary ...
might be able to just remove from the collection entirely (2) need to
finalize removal apis
- [ ] Try replacing the "channel based" asset id recycling with
something a bit more efficient (ex: we might be able to use raw atomic
ints with some cleverness)
- [ ] Consider adding UUIDs to processed assets (scoped just to helping
identify moved assets ... not exposed to load queries ... see [Next
Steps](#next-steps))
- [ ] Store "last modified" source asset and meta timestamps in
processed meta files to enable skipping expensive hashing when the file
wasn't changed
- [ ] Fix "slow loop" handle drop fix
- [ ] Migrate to TypeName
- [x] Handle "loader preregistration". See #9429
## Next Steps
* **Configurable per-type defaults for AssetMeta**: It should be
possible to add configuration like "all png image meta should default to
using nearest sampling" (currently this hard-coded per-loader/processor
Settings::default() impls). Also see the "Folder Meta" bullet point.
* **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical
asset ids" discussion in [Open Questions](#open-questions) and the
relevant bullet point in [Draft TODO](#draft-todo). Even without
canonical ids, folder renames could avoid reprocessing in some cases.
* **Multiple Asset Sources**: Expand AssetPath to support "asset source
names" and support multiple AssetReaders in the asset server (ex:
`webserver://some_path/image.png` backed by an Http webserver
AssetReader). The "default" asset reader would use normal
`some_path/image.png` paths. Ideally this works in combination with
multiple AssetWatchers for hot-reloading
* **Stable Type Names**: this pr removes the TypeUuid requirement from
assets in favor of `std::any::type_name`. This makes defining assets
easier (no need to generate a new uuid / use weird proc macro syntax).
It also makes reading meta files easier (because things have "friendly
names"). We also use type names for components in scene files. If they
are good enough for components, they are good enough for assets. And
consistency across Bevy pillars is desirable. However,
`std::any::type_name` is not guaranteed to be stable (although in
practice it is). We've developed a [stable type
path](https://github.com/bevyengine/bevy/pull/7184) to resolve this,
which should be adopted when it is ready.
* **Command Line Interface**: It should be possible to run the asset
processor in a separate process from the command line. This will also
require building a network-server-backed AssetReader to communicate
between the app and the processor. We've been planning to build a "bevy
cli" for awhile. This seems like a good excuse to build it.
* **Asset Packing**: This is largely an additive feature, so it made
sense to me to punt this until we've laid the foundations in this PR.
* **Per-Platform Processed Assets**: It should be possible to generate
assets for multiple platforms by supporting multiple "processor
profiles" per asset (ex: compress with format X on PC and Y on iOS). I
think there should probably be arbitrary "profiles" (which can be
separate from actual platforms), which are then assigned to a given
platform when generating the final asset distribution for that platform.
Ex: maybe devs want a "Mobile" profile that is shared between iOS and
Android. Or a "LowEnd" profile shared between web and mobile.
* **Versioning and Migrations**: Assets, Loaders, Savers, and Processors
need to have versions to determine if their schema is valid. If an asset
/ loader version is incompatible with the current version expected at
runtime, the processor should be able to migrate them. I think we should
try using Bevy Reflect for this, as it would allow us to load the old
version as a dynamic Reflect type without actually having the old Rust
type. It would also allow us to define "patches" to migrate between
versions (Bevy Reflect devs are currently working on patching). The
`.meta` file already has its own format version. Migrating that to new
versions should also be possible.
* **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write
type) currently used by AssetPath can still result in String clones that
aren't actually necessary (cloning an Owned Cow clones the contents).
Bevy's asset system requires cloning AssetPaths in a number of places,
which result in actual clones of the internal Strings. This is not
efficient. AssetPath internals should be reworked to exhibit truer
cow-like-behavior that reduces String clones to the absolute minimum.
* **Consider processor-less processing**: In theory the AssetServer
could run processors "inline" even if the background AssetProcessor is
disabled. If we decide this is actually desirable, we could add this.
But I don't think its a priority in the short or medium term.
* **Pre-emptive dependency loading**: We could encode dependencies in
processed meta files, which could then be used by the Asset Server to
kick of dependency loads as early as possible (prior to starting the
actual asset load). Is this desirable? How much time would this save in
practice?
* **Optimize Processor With UntypedAssetIds**: The processor exclusively
uses AssetPath to identify assets currently. It might be possible to
swap these out for UntypedAssetIds in some places, which are smaller /
cheaper to hash and compare.
* **One to Many Asset Processing**: An asset source file that produces
many assets currently must be processed into a single "processed" asset
source. If labeled assets can be written separately they can each have
their own configured savers _and_ they could be loaded more granularly.
Definitely worth exploring!
* **Automatically Track "Runtime-only" Asset Dependencies**: Right now,
tracking "created at runtime" asset dependencies requires adding them
via `asset_server.load_asset(StandardMaterial::default())`. I think with
some cleverness we could also do this for
`materials.add(StandardMaterial::default())`, making tracking work
"everywhere". There are challenges here relating to change detection /
ensuring the server is made aware of dependency changes. This could be
expensive in some cases.
* **"Dependency Changed" events**: Some assets have runtime artifacts
that need to be re-generated when one of their dependencies change (ex:
regenerate a material's bind group when a Texture needs to change). We
are generating the dependency graph so we can definitely produce these
events. Buuuuut generating these events will have a cost / they could be
high frequency for some assets, so we might want this to be opt-in for
specific cases.
* **Investigate Storing More Information In Handles**: Handles can now
store arbitrary information, which makes it cheaper and easier to
access. How much should we move into them? Canonical asset load states
(via atomics)? (`handle.is_loaded()` would be very cool). Should we
store the entire asset and remove the `Assets<T>` collection?
(`Arc<RwLock<Option<Image>>>`?)
* **Support processing and loading files without extensions**: This is a
pretty arbitrary restriction and could be supported with very minimal
changes.
* **Folder Meta**: It would be nice if we could define per folder
processor configuration defaults (likely in a `.meta` or `.folder_meta`
file). Things like "default to linear filtering for all Images in this
folder".
* **Replace async_broadcast with event-listener?** This might be
approximately drop-in for some uses and it feels more light weight
* **Support Running the AssetProcessor on the Web**: Most of the hard
work is done here, but there are some easy straggling TODOs (make the
transaction log an interface instead of a direct file writer so we can
write a web storage backend, implement an AssetReader/AssetWriter that
reads/writes to something like LocalStorage).
* **Consider identifying and preventing circular dependencies**: This is
especially important for "processor dependencies", as processing will
silently never finish in these cases.
* **Built-in/Inlined Asset Hot Reloading**: This PR regresses
"built-in/inlined" asset hot reloading (previously provided by the
DebugAssetServer). I'm intentionally punting this because I think it can
be cleanly implemented with "multiple asset sources" by registering a
"debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset
paths) in combination with an AssetWatcher for that asset source and
support for "manually loading pats with asset bytes instead of
AssetReaders". The old DebugAssetServer was quite nasty and I'd love to
avoid that hackery going forward.
* **Investigate ways to remove double-parsing meta files**: Parsing meta
files currently involves parsing once with "minimal" versions of the
meta file to extract the type name of the loader/processor config, then
parsing again to parse the "full" meta. This is suboptimal. We should be
able to define custom deserializers that (1) assume the loader/processor
type name comes first (2) dynamically looks up the loader/processor
registrations to deserialize settings in-line (similar to components in
the bevy scene format). Another alternative: deserialize as dynamic
Reflect objects and then convert.
* **More runtime loading configuration**: Support using the Handle type
as a hint to select an asset loader (instead of relying on AssetPath
extensions)
* **More high level Processor trait implementations**: For example, it
might be worth adding support for arbitrary chains of "asset transforms"
that modify an in-memory asset representation between loading and
saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by
a `flip_normals` transform, then save the mesh to an efficient
compressed format).
* **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO
item](#draft-todo) for context)
* **Explore High Level Load Interfaces**: See [this
discussion](#discuss-on_loaded-high-level-interface) for one prototype.
* **Asset Streaming**: It would be great if we could stream Assets (ex:
stream a long video file piece by piece)
* **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than
they need to be because they have a Uuid enum variant. If we implement
an "id exchanging" system that trades Uuids for "efficient runtime ids",
we can cut down on the size of AssetIds, making them more efficient.
This has some open design questions, such as how to spawn entities with
"default" handle values (as these wouldn't have access to the exchange
api in the current system).
* **Asset Path Fixup Tooling**: Assets that inline asset paths inside
them will break when an asset moves. The asset system provides the
functionality to detect when paths break. We should build a framework
that enables formats to define "path migrations". This is especially
important for scene files. For editor-generated files, we should also
consider using UUIDs (see other bullet point) to avoid the need to
migrate in these cases.
---------
Co-authored-by: BeastLe9enD <beastle9end@outlook.de>
Co-authored-by: Mike <mike.hsu@gmail.com>
Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
# Objective
Fix#8267.
Fixes half of #7840.
The `ComputedVisibility` component contains two flags: hierarchy
visibility, and view visibility (whether its visible to any cameras).
Due to the modular and open-ended way that view visibility is computed,
it triggers change detection every single frame, even when the value
does not change. Since hierarchy visibility is stored in the same
component as view visibility, this means that change detection for
inherited visibility is completely broken.
At the company I work for, this has become a real issue. We are using
change detection to only re-render scenes when necessary. The broken
state of change detection for computed visibility means that we have to
to rely on the non-inherited `Visibility` component for now. This is
workable in the early stages of our project, but since we will
inevitably want to use the hierarchy, we will have to either:
1. Roll our own solution for computed visibility.
2. Fix the issue for everyone.
## Solution
Split the `ComputedVisibility` component into two: `InheritedVisibilty`
and `ViewVisibility`.
This allows change detection to behave properly for
`InheritedVisibility`.
View visiblity is still erratic, although it is less useful to be able
to detect changes
for this flavor of visibility.
Overall, this actually simplifies the API. Since the visibility system
consists of
self-explaining components, it is much easier to document the behavior
and usage.
This approach is more modular and "ECS-like" -- one could
strip out the `ViewVisibility` component entirely if it's not needed,
and rely only on inherited visibility.
---
## Changelog
- `ComputedVisibility` has been removed in favor of:
`InheritedVisibility` and `ViewVisiblity`.
## Migration Guide
The `ComputedVisibilty` component has been split into
`InheritedVisiblity` and
`ViewVisibility`. Replace any usages of
`ComputedVisibility::is_visible_in_hierarchy`
with `InheritedVisibility::get`, and replace
`ComputedVisibility::is_visible_in_view`
with `ViewVisibility::get`.
```rust
// Before:
commands.spawn(VisibilityBundle {
visibility: Visibility::Inherited,
computed_visibility: ComputedVisibility::default(),
});
// After:
commands.spawn(VisibilityBundle {
visibility: Visibility::Inherited,
inherited_visibility: InheritedVisibility::default(),
view_visibility: ViewVisibility::default(),
});
```
```rust
// Before:
fn my_system(q: Query<&ComputedVisibilty>) {
for vis in &q {
if vis.is_visible_in_hierarchy() {
// After:
fn my_system(q: Query<&InheritedVisibility>) {
for inherited_visibility in &q {
if inherited_visibility.get() {
```
```rust
// Before:
fn my_system(q: Query<&ComputedVisibilty>) {
for vis in &q {
if vis.is_visible_in_view() {
// After:
fn my_system(q: Query<&ViewVisibility>) {
for view_visibility in &q {
if view_visibility.get() {
```
```rust
// Before:
fn my_system(mut q: Query<&mut ComputedVisibilty>) {
for vis in &mut q {
vis.set_visible_in_view();
// After:
fn my_system(mut q: Query<&mut ViewVisibility>) {
for view_visibility in &mut q {
view_visibility.set();
```
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
# Objective
- The current `EventReader::iter` has been determined to cause confusion
among new Bevy users. It was suggested by @JoJoJet to rename the method
to better clarify its usage.
- Solves #9624
## Solution
- Rename `EventReader::iter` to `EventReader::read`.
- Rename `EventReader::iter_with_id` to `EventReader::read_with_id`.
- Rename `ManualEventReader::iter` to `ManualEventReader::read`.
- Rename `ManualEventReader::iter_with_id` to
`ManualEventReader::read_with_id`.
---
## Changelog
- `EventReader::iter` has been renamed to `EventReader::read`.
- `EventReader::iter_with_id` has been renamed to
`EventReader::read_with_id`.
- `ManualEventReader::iter` has been renamed to
`ManualEventReader::read`.
- `ManualEventReader::iter_with_id` has been renamed to
`ManualEventReader::read_with_id`.
- Deprecated `EventReader::iter`
- Deprecated `EventReader::iter_with_id`
- Deprecated `ManualEventReader::iter`
- Deprecated `ManualEventReader::iter_with_id`
## Migration Guide
- Existing usages of `EventReader::iter` and `EventReader::iter_with_id`
will have to be changed to `EventReader::read` and
`EventReader::read_with_id` respectively.
- Existing usages of `ManualEventReader::iter` and
`ManualEventReader::iter_with_id` will have to be changed to
`ManualEventReader::read` and `ManualEventReader::read_with_id`
respectively.
# Objective
Rename `Val`'s `evaluate` method to `resolve`.
Implement `resolve` support for `Val`'s viewport variants.
fixes#9535
---
## Changelog
`bevy_ui::ui_node::Val`:
* Renamed the following methods and added a `viewport_size` parameter:
- `evaluate` to `resolve`
- `try_add_with_size` to `try_add_with_context`
- `try_add_assign_with_size` to `try_add_assign_with_context`
- `try_sub_with_size` to `try_sub_with_context`
- `try_sub_assign_with_size` to `try_sub_assign_with_context`
* Implemented `resolve` support for `Val`'s viewport coordinate types
## Migration Guide
* Renamed the following `Val` methods and added a `viewport_size`
parameter:
- `evaluate` to `resolve`
- `try_add_with_size` to `try_add_with_context`
- `try_add_assign_with_size` to `try_add_assign_with_context`
- `try_sub_with_size` to `try_sub_with_context`
- `try_sub_assign_with_size` to `try_sub_assign_with_context`
Legitimately, bevy emits a WARN when encountering entities in UI trees
without NodeBunlde components.
Bevy pretty much always panics when such a thing happens, due to the
update_clipping system.
However, sometimes, it's perfectly legitimate to have a child without UI
nodes in a UI tree. For example, as a "seed" entity that is consumed by
a 3rd party plugin, which will later spawn a valid UI tree. In loading
scenarios, you are pretty much guaranteed to have incomplete children.
The presence of the WARN hints that bevy does not intend to panic on
such occasion (otherwise the warn! would be a panic!) so I assume panic
is an unintended behavior, aka a bug.
## Solution
Early-return instead of panicking.
I did only test that it indeed fixed the panic, not checked for UI
inconsistencies. Though on a logical level, it can only have changed
code that would otherwise panic.
## Alternatives
Instead of early-returning on invalid entity in `update_clipping`, do
not call it with invalid entity in its recursive call.
---
## Changelog
- Do not panic on non-UI child of UI entity
# Objective
Doc comment for the `global_transform` field in `NodeBundle` says:
```
/// This field is automatically managed by the UI layout system.
```
The `GlobalTransform` component is the thing being managed, not the
`global_transform` field, and the `TransformPropagate` systems do the
managing, not the UI layout system.
# Objective
* There is no way to read the fields of `GridPlacement` once set.
* Values of `0` for `GridPlacement`'s fields are invalid but can be set.
* A non-zero representation would be half the size.
fixes#9474
## Solution
* Add `get_start`, `get_end` and `get_span` accessor methods.
* Change`GridPlacement`'s constructor functions to panic on arguments of
zero.
* Use non-zero types instead of primitives for `GridPlacement`'s fields.
---
## Changelog
`bevy_ui::ui_node::GridPlacement`:
* Field types have been changed to `Option<NonZeroI16>` and
`Option<NonZeroU16>`. This is because zero values are not valid for
`GridPlacement`. Previously, Taffy interpreted these as auto variants.
* Constructor functions for `GridPlacement` panic on arguments of `0`.
* Added accessor functions: `get_start`, `get_end`, and `get_span`.
These return the inner primitive value (if present) of the respective
fields.
## Migration Guide
`GridPlacement`'s constructor functions no longer accept values of `0`.
Given any argument of `0` they will panic with a `GridPlacementError`.
## Objective
- `bevy_text/src/pipeline.rs` had some crufty code.
## Solution
Remove the cruft.
- `&mut self` argument was unused by
`TextPipeline::create_text_measure`, so we replace it with a constructor
`TextMeasureInfo::from_text`.
- We also pass a `&Text` to `from_text` since there is no reason to
split the struct before passing it as argument.
- from_text also checks beforehand that every Font exist in the
Assets<Font>. This allows rust to skip the drop code on the Vecs we
create in the method, since there is no early exit.
- We also remove the scaled_fonts field on `TextMeasureInfo`. This
avoids an additional allocation. We can re-use the font on `fonts`
instead in `compute_size`. Building a `ScaledFont` seems fairly cheap,
when looking at the ab_glyph internals.
- We also implement ToSectionText on TextMeasureSection, this let us
skip creating a whole new Vec each time we call compute_size.
- This let us remove compute_size_from_section_text, since its only
purpose was to not have to allocate the Vec we just made redundant.
- Make some immutabe `Vec<T>` into `Box<[T]>` and `String` into
`Box<str>`
- `{min,max}_width_content_size` fields of `TextMeasureInfo` have name
`width` in them, yet the contain information on both width and height.
- `TextMeasureInfo::linebreak_behaviour` -> `linebreak_behavior`
## Migration Guide
- The `ResMut<TextPipeline>` argument to `measure_text_system` doesn't
exist anymore. If you were calling this system manually, you should
remove the argument.
- The `{min,max}_width_content_size` fields of `TextMeasureInfo` are
renamed to `min` and `max` respectively
- Other changes to `TextMeasureInfo` may also break your code if you
were manually building it. Please consider using the new
`TextMeasureInfo::from_text` to build one instead.
- `TextPipeline::create_text_measure` has been removed in favor of
`TextMeasureInfo::from_text`
# Objective
- Fix the `borders`, `ui` and `text_wrap_debug` examples.
## Solution
- Swap `TransparentUi` to use a stable sort
---
This is the smallest change to fix the examples but ideally this is
fixed by setting better sort keys for the UI elements such that we can
swap back to an unstable sort.
This is a continuation of this PR: #8062
# Objective
- Reorder render schedule sets to allow data preparation when phase item
order is known to support improved batching
- Part of the batching/instancing etc plan from here:
https://github.com/bevyengine/bevy/issues/89#issuecomment-1379249074
- The original idea came from @inodentry and proved to be a good one.
Thanks!
- Refactor `bevy_sprite` and `bevy_ui` to take advantage of the new
ordering
## Solution
- Move `Prepare` and `PrepareFlush` after `PhaseSortFlush`
- Add a `PrepareAssets` set that runs in parallel with other systems and
sets in the render schedule.
- Put prepare_assets systems in the `PrepareAssets` set
- If explicit dependencies are needed on Mesh or Material RenderAssets
then depend on the appropriate system.
- Add `ManageViews` and `ManageViewsFlush` sets between
`ExtractCommands` and Queue
- Move `queue_mesh*_bind_group` to the Prepare stage
- Rename them to `prepare_`
- Put systems that prepare resources (buffers, textures, etc.) into a
`PrepareResources` set inside `Prepare`
- Put the `prepare_..._bind_group` systems into a `PrepareBindGroup` set
after `PrepareResources`
- Move `prepare_lights` to the `ManageViews` set
- `prepare_lights` creates views and this must happen before `Queue`
- This system needs refactoring to stop handling all responsibilities
- Gather lights, sort, and create shadow map views. Store sorted light
entities in a resource
- Remove `BatchedPhaseItem`
- Replace `batch_range` with `batch_size` representing how many items to
skip after rendering the item or to skip the item entirely if
`batch_size` is 0.
- `queue_sprites` has been split into `queue_sprites` for queueing phase
items and `prepare_sprites` for batching after the `PhaseSort`
- `PhaseItem`s are still inserted in `queue_sprites`
- After sorting adjacent compatible sprite phase items are accumulated
into `SpriteBatch` components on the first entity of each batch,
containing a range of vertex indices. The associated `PhaseItem`'s
`batch_size` is updated appropriately.
- `SpriteBatch` items are then drawn skipping over the other items in
the batch based on the value in `batch_size`
- A very similar refactor was performed on `bevy_ui`
---
## Changelog
Changed:
- Reordered and reworked render app schedule sets. The main change is
that data is extracted, queued, sorted, and then prepared when the order
of data is known.
- Refactor `bevy_sprite` and `bevy_ui` to take advantage of the
reordering.
## Migration Guide
- Assets such as materials and meshes should now be created in
`PrepareAssets` e.g. `prepare_assets<Mesh>`
- Queueing entities to `RenderPhase`s continues to be done in `Queue`
e.g. `queue_sprites`
- Preparing resources (textures, buffers, etc.) should now be done in
`PrepareResources`, e.g. `prepare_prepass_textures`,
`prepare_mesh_uniforms`
- Prepare bind groups should now be done in `PrepareBindGroups` e.g.
`prepare_mesh_bind_group`
- Any batching or instancing can now be done in `Prepare` where the
order of the phase items is known e.g. `prepare_sprites`
## Next Steps
- Introduce some generic mechanism to ensure items that can be batched
are grouped in the phase item order, currently you could easily have
`[sprite at z 0, mesh at z 0, sprite at z 0]` preventing batching.
- Investigate improved orderings for building the MeshUniform buffer
- Implementing batching across the rest of bevy
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
# Objective
- Fixes#9533
## Solution
* Added `Val::ZERO` as a constant which is defined as `Val::Px(0.)`.
* Added manual `PartialEq` implementation for `Val` which allows any
zero value to equal any other zero value. E.g., `Val::Px(0.) ==
Val::Percent(0.)` etc. This is technically a breaking change, as
`Val::Px(0.) == Val::Percent(0.)` now equals `true` instead of `false`
(as an example)
* Replaced instances of `Val::Px(0.)`, `Val::Percent(0.)`, etc. with
`Val::ZERO`
* Fixed `bevy_ui::layout::convert::tests::test_convert_from` test to
account for Taffy not equating `Points(0.)` and `Percent(0.)`. These
tests now use `assert_eq!(...)` instead of `assert!(matches!(...))`
which gives easier to diagnose error messages.
# Objective
[Rust 1.72.0](https://blog.rust-lang.org/2023/08/24/Rust-1.72.0.html) is
now stable.
# Notes
- `let-else` formatting has arrived!
- I chose to allow `explicit_iter_loop` due to
https://github.com/rust-lang/rust-clippy/issues/11074.
We didn't hit any of the false positives that prevent compilation, but
fixing this did produce a lot of the "symbol soup" mentioned, e.g. `for
image in &mut *image_events {`.
Happy to undo this if there's consensus the other way.
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
Fixes incorrect docs in `bevy_ui` for `JustifyItems` and `JustifySelf`.
## Solution
`JustifyItems` and `JustifySelf` target the main axis and not the cross
axis.
# Objective
`round_ties_up` checks the predicate:
```rust
0. <= value || value.fract() != 0.5
```
which is meant to determine if the value is negative with a fractional
part of `0.5`.
However given a negative value, `fract` returns a negative fraction so
the predicate is true for all numeric values and `ceil` is never called.
## Solution
Changed the predicate to `value.fract() != -0.5` and added a test.
Also improved the comments a bit.
# Objective
- A few of the `const DEFAULT` properties of the grid feature are not
marked as pub. This is an issue because it means you can't have a
`const` `Style` declaration anymore. Most of the existing properties are
already pub.
## Solution
- add the missing pub
# Objective
- Resolves https://github.com/bevyengine/bevy/issues/9440
## Solution
- Remove the doc string mentioning the position of a `NodeBundle`, since
the doc string for the `style` component already explains this ability.
# Objective
Inconvenient initialization of `UiScale`
## Solution
Change `UiScale` to a tuple struct
## Migration Guide
Replace initialization of `UiScale` like ```UiScale { scale: 1.0 }```
with ```UiScale(1.0)```
# Objective
The default for `ContentSize` should have the `measure_func` field set
to `None`, instead of a fixed size of zero. This means that until a
measure func is set the size of the UI node will be determined by its
`Style` constraints. This is preferable as it allows users to specify
the space the Node should take up in the layout while waiting for
content to load.
## Solution
Derive `Default` for `ContentSize`.
The PR also adds a `fixed_size` helper function to make it a bit easier
to access the old behaviour.
## Changelog
* Derived `Default` for `ContentSize`
* Added a `fixed_size` helper function to `ContentSize` that creates a
new `ContentSize` with a `MeasureFunc` that always returns the same
value, regardless of layout constraints.
## Migration Guide
The default for `ContentSize` now sets its `measure_func` to `None`,
instead of a fixed size measure that returns `Vec2::ZERO`.
The helper function `fixed_size` can be called with
`ContentSize::fixed_size(Vec2::ZERO)` to get the previous behaviour.
# Objective
The doc comment for `text_system` is not quite correct. It implies that
a new `TextLayoutInfo` is generated on changes to `Text` and `Style`.
While changes to those components might indirectly trigger a
regeneration of the text layout, `text_system` itself only queries for
changes to `Node`
Also added details to `measure_text_system`'s doc comments explaining
how it reacts to changes.
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
This doc comment for the `set` method of `ContentSize`:
```
Set a `Measure` for this function
```
doesn't seem to make sense, `ContentSize` is not a function.
# Solution
Replace it.
# Objective
Remove the `With<Parent>` query filter from the `parent_node_query`
parameter of the `bevy_ui::render::extract_uinode_borders` function.
This is a bug, the query is only used to retrieve the size of the
current node's parent. We don't care if that parent node has a `Parent`
or not.
---------
Co-authored-by: François <mockersf@gmail.com>
The previous formatting didn't render as you'd expect, with 'For CSS
Grid containers' getting adopted by the prior bullet point. Rather than
fixing that directly I opted for a slight reformatting for consistency
with other fields, notably left/right/top/bottom.
# Objective
Fixes https://github.com/bevyengine/bevy/issues/9234
re-breaks: The issues that were linked in #9169
## Solution
Revert the PR that broke tonemapping/postprocessing/etc.
Any passes that are post msaa resolve need to use the main textures, not
the msaa texture.
## Changelog
Idk what to put here since it's a revert.
# Objective
Fixes#9097
## Solution
Reorder the `ExtractSchedule` so that the `extract_text_uinodes` and
`extract_uinode_borders` systems are run after `extract_atlas_uinodes`.
## Changelog
`bevy_ui::render`:
* Added the `ExtractAtlasNode` variant to `RenderUiSystem`.
* Changed `ExtractSchedule` so that `extract_uinode_borders` and
`extract_text_uinodes` run after `extract_atlas_uinodes`.
# Objective
Fixes#8894Fixes#7944
## Solution
The UI pipeline's `MultisampleState::count` is set to 1 whereas the
`MultisampleState::count` for the camera's ViewTarget is taken from the
`Msaa` resource, and corruption occurs when these two values are
different.
This PR solves the problem by setting `MultisampleState::count` for the
UI pipeline to the value from the Msaa resource too.
I don't know much about Bevy's rendering internals or graphics hardware,
so maybe there is a better solution than this. UI MSAA was probably
disabled for a good reason (performance?).
## Changelog
* Enabled multisampling for the UI pipeline.
# Objective
Continue #7867 now that we have URect #7984
- Return `URect` instead of `(UVec2, UVec2)` in
`Camera::physical_viewport_rect`
- Add `URect` and `IRect` to prelude
## Changelog
- Changed `Camera::physical_viewport_rect` return type from `(UVec2,
UVec2)` to `URect`
- `URect` and `IRect` were added to prelude
## Migration Guide
Before:
```rust
fn view_physical_camera_rect(camera_query: Query<&Camera>) {
let camera = camera_query.single();
let Some((min, max)) = camera.physical_viewport_rect() else { return };
dbg!(min, max);
}
```
After:
```rust
fn view_physical_camera_rect(camera_query: Query<&Camera>) {
let camera = camera_query.single();
let Some(URect { min, max }) = camera.physical_viewport_rect() else { return };
dbg!(min, max);
}
```
# Objective
`ExtractedUiNodes` is cleared by the `extract_uinodes` function during
the extraction schedule. Because the Bevy UI renderer uses a painters
algorithm, this makes it impossible for users to create a custom
extraction function that adds items for a node to be drawn behind the
rectangle added by `extract_uniodes`.
## Solution
Drain `ExtractedUiNodes` in `prepare_ui_nodes` instead, after the
extraction schedule has finished.
# Objective
Fix typos throughout the project.
## Solution
[`typos`](https://github.com/crate-ci/typos) project was used for
scanning, but no automatic corrections were applied. I checked
everything by hand before fixing.
Most of the changes are documentation/comments corrections. Also, there
are few trivial changes to code (variable name, pub(crate) function name
and a few error/panic messages).
## Unsolved
`bevy_reflect_derive` has
[typo](1b51053f19/crates/bevy_reflect/bevy_reflect_derive/src/type_path.rs (L76))
in enum variant name that I didn't fix. Enum is `pub(crate)`, so there
shouldn't be any trouble if fixed. However, code is tightly coupled with
macro usage, so I decided to leave it for more experienced contributor
just in case.
# Objective
fixes#8911, #7712
## Solution
Rounding was added to Taffy which fixed issue #7712.
The implementation uses the f32 `round` method which rounds ties
(fractional part is a half) away from zero. Issue #8911 occurs when a
node's min and max bounds on either axis are "ties" and zero is between
them. Then the bounds are rounded away from each other, and the node
grows by a pixel. This alone shouldn't cause the node to expand
continuously, but I think there is some interaction with the way Taffy
recomputes a layout from its cached data that I didn't identify.
This PR fixes#8911 by first disabling Taffy's internal rounding and
using an alternative rounding function that rounds ties up.
Then, instead of rounding the values of the internal layout tree as
Taffy's built-in rounding does, we leave those values unmodified and
only the values stored in the components are rounded. This requires
walking the tree for the UI node geometry update rather than iterating
through a query.
Because the component values are regenerated each update, that should
mean that UI updates are idempotent (ish) now and make the growing node
behaviour seen in issue #8911 impossible.
I expected a performance regression, but it's an improvement on main:
```
cargo run --profile stress-test --features trace_tracy --example many_buttons
```
<img width="461" alt="ui-rounding-fix-compare"
src="https://github.com/bevyengine/bevy/assets/27962798/914bfd50-e18a-4642-b262-fafa69005432">
I guess it makes sense to do the rounding together with the node size
and position updates.
---
## Changelog
`bevy_ui::layout`:
* Taffy's built-in rounding is disabled and rounding is now performed by
`ui_layout_system`.
* Instead of rounding the values of the internal layout tree as Taffy's
built-in rounding does, we leave those values unmodified and only the
values stored in the components are rounded. This requires walking the
tree for the UI node geometry update rather than iterating through a
query. Because the component values are regenerated each update, that
should mean that UI updates are idempotent now and make the growing node
behaviour seen in issue #8911 impossible.
* Added two helper functions `round_ties_up` and
`round_layout_coordinates`.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
After the UI layout is computed when the coordinates are converted back
from physical coordinates to logical coordinates the `UiScale` is
ignored. This results in a confusing situation where we have two
different systems of logical coordinates.
Example:
```rust
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, update)
.run();
}
fn setup(mut commands: Commands, mut ui_scale: ResMut<UiScale>) {
ui_scale.scale = 4.;
commands.spawn(Camera2dBundle::default());
commands.spawn(NodeBundle {
style: Style {
align_items: AlignItems::Center,
justify_content: JustifyContent::Center,
width: Val::Percent(100.),
..Default::default()
},
..Default::default()
})
.with_children(|builder| {
builder.spawn(NodeBundle {
style: Style {
width: Val::Px(100.),
height: Val::Px(100.),
..Default::default()
},
background_color: Color::MAROON.into(),
..Default::default()
}).with_children(|builder| {
builder.spawn(TextBundle::from_section("", TextStyle::default());
});
});
}
fn update(
mut text_query: Query<(&mut Text, &Parent)>,
node_query: Query<Ref<Node>>,
) {
for (mut text, parent) in text_query.iter_mut() {
let node = node_query.get(parent.get()).unwrap();
if node.is_changed() {
text.sections[0].value = format!("size: {}", node.size());
}
}
}
```
result:
We asked for a 100x100 UI node but the Node's size is multiplied by the
value of `UiScale` to give a logical size of 400x400.
## Solution
Divide the output physical coordinates by `UiScale` in
`ui_layout_system` and multiply the logical viewport size by `UiScale`
when creating the projection matrix for the UI's `ExtractedView` in
`extract_default_ui_camera_view`.
---
## Changelog
* The UI layout's physical coordinates are divided by both the window
scale factor and `UiScale` when converting them back to logical
coordinates. The logical size of Ui nodes now matches the values given
to their size constraints.
* Multiply the logical viewport size by `UiScale` before creating the
projection matrix for the UI's `ExtractedView` in
`extract_default_ui_camera_view`.
* In `ui_focus_system` the cursor position returned from `Window` is
divided by `UiScale`.
* Added a scale factor parameter to `Node::physical_size` and
`Node::physical_rect`.
* The example `viewport_debug` now uses a `UiScale` of 2. to ensure that
viewport coordinates are working correctly with a non-unit `UiScale`.
## Migration Guide
Physical UI coordinates are now divided by both the `UiScale` and the
window's scale factor to compute the logical sizes and positions of UI
nodes.
This ensures that UI Node size and position values, held by the `Node`
and `GlobalTransform` components, conform to the same logical coordinate
system as the style constraints from which they are derived,
irrespective of the current `scale_factor` and `UiScale`.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Fix#8984
### Solution
- Address compilation errors
I admit: I did sneak it an unrelated mini-refactor. of the
`measurment.rs` module. it seemed to me that directly importing `taffy`
types helped reduce a lot of boilerplate, so I did it.
# Objective
**This implementation is based on
https://github.com/bevyengine/rfcs/pull/59.**
---
Resolves#4597
Full details and motivation can be found in the RFC, but here's a brief
summary.
`FromReflect` is a very powerful and important trait within the
reflection API. It allows Dynamic types (e.g., `DynamicList`, etc.) to
be formed into Real ones (e.g., `Vec<i32>`, etc.).
This mainly comes into play concerning deserialization, where the
reflection deserializers both return a `Box<dyn Reflect>` that almost
always contain one of these Dynamic representations of a Real type. To
convert this to our Real type, we need to use `FromReflect`.
It also sneaks up in other ways. For example, it's a required bound for
`T` in `Vec<T>` so that `Vec<T>` as a whole can be made `FromReflect`.
It's also required by all fields of an enum as it's used as part of the
`Reflect::apply` implementation.
So in other words, much like `GetTypeRegistration` and `Typed`, it is
very much a core reflection trait.
The problem is that it is not currently treated like a core trait and is
not automatically derived alongside `Reflect`. This makes using it a bit
cumbersome and easy to forget.
## Solution
Automatically derive `FromReflect` when deriving `Reflect`.
Users can then choose to opt-out if needed using the
`#[reflect(from_reflect = false)]` attribute.
```rust
#[derive(Reflect)]
struct Foo;
#[derive(Reflect)]
#[reflect(from_reflect = false)]
struct Bar;
fn test<T: FromReflect>(value: T) {}
test(Foo); // <-- OK
test(Bar); // <-- Panic! Bar does not implement trait `FromReflect`
```
#### `ReflectFromReflect`
This PR also automatically adds the `ReflectFromReflect` (introduced in
#6245) registration to the derived `GetTypeRegistration` impl— if the
type hasn't opted out of `FromReflect` of course.
<details>
<summary><h4>Improved Deserialization</h4></summary>
> **Warning**
> This section includes changes that have since been descoped from this
PR. They will likely be implemented again in a followup PR. I am mainly
leaving these details in for archival purposes, as well as for reference
when implementing this logic again.
And since we can do all the above, we might as well improve
deserialization. We can now choose to deserialize into a Dynamic type or
automatically convert it using `FromReflect` under the hood.
`[Un]TypedReflectDeserializer::new` will now perform the conversion and
return the `Box`'d Real type.
`[Un]TypedReflectDeserializer::new_dynamic` will work like what we have
now and simply return the `Box`'d Dynamic type.
```rust
// Returns the Real type
let reflect_deserializer = UntypedReflectDeserializer::new(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
let output: SomeStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?;
// Returns the Dynamic type
let reflect_deserializer = UntypedReflectDeserializer::new_dynamic(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
let output: DynamicStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?;
```
</details>
---
## Changelog
* `FromReflect` is now automatically derived within the `Reflect` derive
macro
* This includes auto-registering `ReflectFromReflect` in the derived
`GetTypeRegistration` impl
* ~~Renamed `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` to
`TypedReflectDeserializer::new_dynamic` and
`UntypedReflectDeserializer::new_dynamic`, respectively~~ **Descoped**
* ~~Changed `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` to automatically convert the
deserialized output using `FromReflect`~~ **Descoped**
## Migration Guide
* `FromReflect` is now automatically derived within the `Reflect` derive
macro. Items with both derives will need to remove the `FromReflect`
one.
```rust
// OLD
#[derive(Reflect, FromReflect)]
struct Foo;
// NEW
#[derive(Reflect)]
struct Foo;
```
If using a manual implementation of `FromReflect` and the `Reflect`
derive, users will need to opt-out of the automatic implementation.
```rust
// OLD
#[derive(Reflect)]
struct Foo;
impl FromReflect for Foo {/* ... */}
// NEW
#[derive(Reflect)]
#[reflect(from_reflect = false)]
struct Foo;
impl FromReflect for Foo {/* ... */}
```
<details>
<summary><h4>Removed Migrations</h4></summary>
> **Warning**
> This section includes changes that have since been descoped from this
PR. They will likely be implemented again in a followup PR. I am mainly
leaving these details in for archival purposes, as well as for reference
when implementing this logic again.
* The reflect deserializers now perform a `FromReflect` conversion
internally. The expected output of `TypedReflectDeserializer::new` and
`UntypedReflectDeserializer::new` is no longer a Dynamic (e.g.,
`DynamicList`), but its Real counterpart (e.g., `Vec<i32>`).
```rust
let reflect_deserializer =
UntypedReflectDeserializer::new_dynamic(®istry);
let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?;
// OLD
let output: DynamicStruct = reflect_deserializer.deserialize(&mut
deserializer)?.take()?;
// NEW
let output: SomeStruct = reflect_deserializer.deserialize(&mut
deserializer)?.take()?;
```
Alternatively, if this behavior isn't desired, use the
`TypedReflectDeserializer::new_dynamic` and
`UntypedReflectDeserializer::new_dynamic` methods instead:
```rust
// OLD
let reflect_deserializer = UntypedReflectDeserializer::new(®istry);
// NEW
let reflect_deserializer =
UntypedReflectDeserializer::new_dynamic(®istry);
```
</details>
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
operate on naga IR directly to improve handling of shader modules.
- give codespan reporting into imported modules
- allow glsl to be used from wgsl and vice-versa
the ultimate objective is to make it possible to
- provide user hooks for core shader functions (to modify light
behaviour within the standard pbr pipeline, for example)
- make automatic binding slot allocation possible
but ... since this is already big, adds some value and (i think) is at
feature parity with the existing code, i wanted to push this now.
## Solution
i made a crate called naga_oil (https://github.com/robtfm/naga_oil -
unpublished for now, could be part of bevy) which manages modules by
- building each module independantly to naga IR
- creating "header" files for each supported language, which are used to
build dependent modules/shaders
- make final shaders by combining the shader IR with the IR for imported
modules
then integrated this into bevy, replacing some of the existing shader
processing stuff. also reworked examples to reflect this.
## Migration Guide
shaders that don't use `#import` directives should work without changes.
the most notable user-facing difference is that imported
functions/variables/etc need to be qualified at point of use, and
there's no "leakage" of visible stuff into your shader scope from the
imports of your imports, so if you used things imported by your imports,
you now need to import them directly and qualify them.
the current strategy of including/'spreading' `mesh_vertex_output`
directly into a struct doesn't work any more, so these need to be
modified as per the examples (e.g. color_material.wgsl, or many others).
mesh data is assumed to be in bindgroup 2 by default, if mesh data is
bound into bindgroup 1 instead then the shader def `MESH_BINDGROUP_1`
needs to be added to the pipeline shader_defs.
# Objective
In Bevy 10.1 and before, the only way to enable text wrapping was to set
a local `Val::Px` width constraint on the text node itself.
`Val::Percent` constraints and constraints on the text node's ancestors
did nothing.
#7779 fixed those problems. But perversely displaying unwrapped text is
really difficult now, and requires users to nest each `TextBundle` in a
`NodeBundle` and apply `min_width` and `max_width` constraints. Some
constructions may even need more than one layer of nesting. I've seen
several people already who have really struggled with this when porting
their projects to main in advance of 0.11.
## Solution
Add a `NoWrap` variant to the `BreakLineOn` enum.
If `NoWrap` is set, ignore any constraints on the width for the text and
call `TextPipeline::queue_text` with a width bound of `f32::INFINITY`.
---
## Changelog
* Added a `NoWrap` variant to the `BreakLineOn` enum.
* If `NoWrap` is set, any constraints on the width for the text are
ignored and `TextPipeline::queue_text` is called with a width bound of
`f32::INFINITY`.
* Changed the `size` field of `FixedMeasure` to `pub`. This shouldn't
have been private, it was always intended to have `pub` visibility.
* Added a `with_no_wrap` method to `TextBundle`.
## Migration Guide
`bevy_text::text::BreakLineOn` has a new variant `NoWrap` that disables
text wrapping for the `Text`.
Text wrapping can also be disabled using the `with_no_wrap` method of
`TextBundle`.
# Objective
- Fix this error to be able to run UI examples in WebGPU
```
1 error(s) generated while compiling the shader:
:31:18 error: integral user-defined vertex outputs must have a flat interpolation attribute
@location(3) mode: u32,
^^^^
:36:1 note: while analyzing entry point 'vertex'
fn vertex(
^^
```
It was introduce in #8793
## Solution
- Add `@interpolate(flat)` to the `mode` field
# Objective
In Bevy main, the unconstrained size of an `ImageBundle` or
`AtlasImageBundle` UI node is based solely on the size of its texture
and doesn't change with window scale factor or `UiScale`.
## Solution
* The size field of each `ImageMeasure` should be multiplied by the
current combined scale factor.
* Each `ImageMeasure` should be updated when the combined scale factor
is changed.
## Example:
```rust
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.insert_resource(UiScale { scale: 1.5 })
.add_systems(Startup, setup)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2dBundle::default());
commands.spawn(NodeBundle {
style: Style {
// The size of the "bevy_logo_dark.png" texture is 520x130 pixels
width: Val::Px(520.),
height: Val::Px(130.),
..Default::default()
},
background_color: Color::RED.into(),
..Default::default()
});
commands
.spawn(ImageBundle {
style: Style {
position_type: PositionType::Absolute,
..Default::default()
},
image: UiImage::new(asset_server.load("bevy_logo_dark.png")),
..Default::default()
});
}
```
The red node is given a size with the same dimensions as the texture. So
we would expect the texture to fill the node exactly.
* Result with Bevy main branch bb59509d44:
<img width="400" alt="image-size-broke"
src="https://github.com/bevyengine/bevy/assets/27962798/19fd927d-ecc5-49a7-be05-c121a8df163f">
* Result with this PR (and Bevy 0.10.1):
<img width="400" alt="image-size-fixed"
src="https://github.com/bevyengine/bevy/assets/27962798/40b47820-5f2d-408f-88ef-9e2beb9c92a0">
---
## Changelog
`bevy_ui::widget::image`
* Update all `ImageMeasure`s on changes to the window scale factor or
`UiScale`.
* Multiply `ImageMeasure::size` by the window scale factor and
`UiScale`.
## Migration Guide
# Objective
`prepare_uinodes` creates a new `UiBatch` whenever the texture changes,
when most often it's just queuing untextured quads. Instead of switching
textures, we can reduce the number of batches generated significantly by
adding a condition to the fragment shader so that it only multiplies by
the `textureSample` value when drawing a textured quad.
# Solution
Add a `mode` field to `UiVertex`.
In `prepare_uinodes` set `mode` to 0 if the quad is textured or 1 if
untextured.
Add a condition to the fragment shader that only multiplies by the
`color` value from `textureSample` if `mode` is set to 1.
---
## Changelog
* Added a `mode` field to `UiVertex`, and added an extra `u32` vertex
attribute to the shader and vertex buffer layout.
* In `prepare_uinodes` mode is set to 0 for the vertices of textured
quads, and 1 if untextured.
* Added a condition to the fragment shader in `ui.wgsl` that only
multiplies by the `color` value from `textureSample` if the mode is
equal to 0.
# Objective
- Better consistency with `add_systems`.
- Deprecating `add_plugin` in favor of a more powerful `add_plugins`.
- Allow passing `Plugin` to `add_plugins`.
- Allow passing tuples to `add_plugins`.
## Solution
- `App::add_plugins` now takes an `impl Plugins` parameter.
- `App::add_plugin` is deprecated.
- `Plugins` is a new sealed trait that is only implemented for `Plugin`,
`PluginGroup` and tuples over `Plugins`.
- All examples, benchmarks and tests are changed to use `add_plugins`,
using tuples where appropriate.
---
## Changelog
### Changed
- `App::add_plugins` now accepts all types that implement `Plugins`,
which is implemented for:
- Types that implement `Plugin`.
- Types that implement `PluginGroup`.
- Tuples (up to 16 elements) over types that implement `Plugins`.
- Deprecated `App::add_plugin` in favor of `App::add_plugins`.
## Migration Guide
- Replace `app.add_plugin(plugin)` calls with `app.add_plugins(plugin)`.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
The "bevy_text" feature attributes for the `PrimaryWindow`, `Window` and
`TextureAtlas` imports in `bevy_ui::render` are used by non-text systems
(`extract_uinode_borders` and `extract_atlas_uinodes`) and need to be
removed.
# Objective
This adds support for using texture atlas sprites in UI. From
discussions today in the ui-dev discord it seems this is a much wanted
feature.
This was previously attempted in #5070 by @ManevilleF however that was
blocked #5103. This work can be easily modified to support #5103 changes
after that merges.
## Solution
I created a new UI bundle that reuses the existing texture atlas
infrastructure. I create a new atlas image component to prevent it from
being drawn by the existing non-UI systems and to remove unused
parameters.
In extract I added new system to calculate the required values for the
texture atlas image, this extracts into the same resource as the
existing UI Image and Text components.
This should have minimal performance impact because if texture atlas is
not present then the exact same code path is followed. Also there should
be no unintended behavior changes because without the new components the
existing systems write the extract same resulting data.
I also added an example showing the sprite working and a system to
advance the animation on space bar presses.
Naming is hard and I would accept any feedback on the bundle name!
---
## Changelog
> Added TextureAtlasImageBundle
---------
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
# Objective
Discovered that PointLight did not implement FromReflect. Adding
FromReflect where Reflect is used. I overreached and applied this rule
everywhere there was a Reflect without a FromReflect, except from where
the compiler wouldn't allow me.
Based from question: https://github.com/bevyengine/bevy/discussions/8774
## Solution
- Adding FromReflect where Reflect was already derived
## Notes
First PR I do in this ecosystem, so not sure if this is the usual
approach, that is, to touch many files at once.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Make the UI code more concise.
## Solution
Add two utility methods to make manipulating `UiRect` from code more
concise:
- `UiRect::px()` create a new `UiRect` like the `new()` function, but
with values in logical pixels directly.
- `UiRect::percent()` is similar, with values as percentages.
This saves a lot of typing and makes UI code more compact while
retaining readability.
---
## Changelog
### Added
Added two new constructors `UiRect::px()` and `UiRect::percent()` to
create a new `UiRect` from values directly specified in logical pixels
and percentages, respectively. The argument order is the same as
`UiRect::new()`, but avoids having to repeat `Val::Px` and
`Val::Percent`, respectively.
# Objective
Implement borders for UI nodes.
Relevant discussion: #7785
Related: #5924, #3991
<img width="283" alt="borders"
src="https://user-images.githubusercontent.com/27962798/220968899-7661d5ec-6f5b-4b0f-af29-bf9af02259b5.PNG">
## Solution
Add an extraction function to draw the borders.
---
Can only do one colour rectangular borders due to the limitations of the
Bevy UI renderer.
Maybe it can be combined with #3991 eventually to add curved border
support.
## Changelog
* Added a component `BorderColor`.
* Added the `extract_uinode_borders` system to the UI Render App.
* Added the UI example `borders`
---------
Co-authored-by: Nico Burns <nico@nicoburns.com>
# Objective
- Some reflect components weren't properly registered.
## Solution
- We register them
- I also sorted the register lines in `Plugin::build` in `bevy_ui`
### Note
How I did I find them:
- I picked up the list of `Component`s from the `Component` trait page
in rustdoc.
- Then I tried to register all of them. Removing the registration when
it doesn't implement `Reflect` to pass compilation.
- Then I added `app.register_type_data::<T, Foo>()`, for all Reflect
components. It panics if `T` is not registered.
- I repeated the last line N times until bevy stopped panicking at
startup
---
## Changelog
- Register the following components: `PrimaryWindow` `Fxaa`
`FogSettings` `NotShadowCaster` `NotShadowReceiver` `CalculatedClip`
`RelativeCursorPosition`
# Objective
This calculation is performed componentwise but all the values are
vectors so it should be using vector operations.
Works correctly with the `relative_cursor_position` example.
# Objective
- Simplify API and make authoring styles easier
See:
https://github.com/bevyengine/bevy/issues/8540#issuecomment-1536177102
## Solution
- The `size`, `min_size`, `max_size`, and `gap` properties have been
replaced by `width`, `height`, `min_width`, `min_height`, `max_width`,
`max_height`, `row_gap`, and `column_gap` properties
---
## Changelog
- Flattened `Style` properties that have a `Size` value directly into
`Style`
## Migration Guide
- The `size`, `min_size`, `max_size`, and `gap` properties have been
replaced by the `width`, `height`, `min_width`, `min_height`,
`max_width`, `max_height`, `row_gap`, and `column_gap` properties. Use
the new properties instead.
---------
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
# Objective
* `Node::physical_rect` divides the logical size of the node by the
scale factor, when it should multiply.
* Add a `physical_size` method to `Node` that calculates the physical
size of a node.
---
## Changelog
* Added a method `physical_size` to `Node` that calculates the physical
size of the `Node` based on the given scale factor.
* Fixed the `Node::physical_rect` method, the logical size should be
multiplied by the scale factor to get the physical size.
* Removed the `scale_value` function from the `text` widget module and
replaced its usage with `Node::physical_size`.
* Derived `Copy` for `Node` (since it's only a wrapped `Vec2`).
* Made `Node::size` const.
# Objective
Replace `Query<&T, Changed<T>>` style queries with the more efficient
`Query<Ref<T>>` form in two of the UI systems.
---
## Changelog
Replaced use of `Changed` with `Ref` in queries in the
`ui_layout_system` and `calc_bounds` UI systems.
# Objective
`text_system` and `measure_text_system` both keep local queues to keep
track of text node entities that need recomputations/remeasurement,
which scales very badly with large numbers of text entities (O(n^2)) and
makes the code quite difficult to understand.
Also `text_system` filters for `Changed<Text>`, this isn't something
that it should do. When a text node entity fails to be processed by
`measure_text_system` because a font can't be found, the text node will
still be added to `text_system`'s local queue for recomputation. `Text`
should only ever be queued by `text_system` when a text node's geometry
is modified or a new measure is added.
## Solution
Remove the local text queues and use a component `TextFlags` to schedule
remeasurements and recomputations.
## Changelog
* Created a component `TextFlags` with fields `remeasure` and
`recompute`, which can be used to schedule a text `remeasure` or
`recomputation` respectively and added it to `TextBundle`.
* Removed the local text queues from `measure_text_system` and
`text_system` and instead use the `TextFlags` component to schedule
remeasurements and recomputations.
## Migration Guide
The component `TextFlags` has been added to `TextBundle`.
# Objective
Copy the `debug::print_tree` function from Taffy except display entity
ids instead of Taffy's node ids and indicate which ui nodes have a
measure func.
# Objective
- Support WebGPU
- alternative to #5027 that doesn't need any async / await
- fixes#8315
- Surprise fix#7318
## Solution
### For async renderer initialisation
- Update the plugin lifecycle:
- app builds the plugin
- calls `plugin.build`
- registers the plugin
- app starts the event loop
- event loop waits for `ready` of all registered plugins in the same
order
- returns `true` by default
- then call all `finish` then all `cleanup` in the same order as
registered
- then execute the schedule
In the case of the renderer, to avoid anything async:
- building the renderer plugin creates a detached task that will send
back the initialised renderer through a mutex in a resource
- `ready` will wait for the renderer to be present in the resource
- `finish` will take that renderer and place it in the expected
resources by other plugins
- other plugins (that expect the renderer to be available) `finish` are
called and they are able to set up their pipelines
- `cleanup` is called, only custom one is still for pipeline rendering
### For WebGPU support
- update the `build-wasm-example` script to support passing `--api
webgpu` that will build the example with WebGPU support
- feature for webgl2 was always enabled when building for wasm. it's now
in the default feature list and enabled on all platforms, so check for
this feature must also check that the target_arch is `wasm32`
---
## Migration Guide
- `Plugin::setup` has been renamed `Plugin::cleanup`
- `Plugin::finish` has been added, and plugins adding pipelines should
do it in this function instead of `Plugin::build`
```rust
// Before
impl Plugin for MyPlugin {
fn build(&self, app: &mut App) {
app.insert_resource::<MyResource>
.add_systems(Update, my_system);
let render_app = match app.get_sub_app_mut(RenderApp) {
Ok(render_app) => render_app,
Err(_) => return,
};
render_app
.init_resource::<RenderResourceNeedingDevice>()
.init_resource::<OtherRenderResource>();
}
}
// After
impl Plugin for MyPlugin {
fn build(&self, app: &mut App) {
app.insert_resource::<MyResource>
.add_systems(Update, my_system);
let render_app = match app.get_sub_app_mut(RenderApp) {
Ok(render_app) => render_app,
Err(_) => return,
};
render_app
.init_resource::<OtherRenderResource>();
}
fn finish(&self, app: &mut App) {
let render_app = match app.get_sub_app_mut(RenderApp) {
Ok(render_app) => render_app,
Err(_) => return,
};
render_app
.init_resource::<RenderResourceNeedingDevice>();
}
}
```
# Objective
fixes#8516
* Give `CalculatedSize` a more specific and intuitive name.
* `MeasureFunc`s should only be updated when their `CalculatedSize` is
modified by the systems managing their content.
For example, suppose that you have a UI displaying an image using an
`ImageNode`. When the window is resized, the node's `MeasureFunc` will
be updated even though the dimensions of the texture contained by the
node are unchanged.
* Fix the `CalculatedSize` API so that it no longer requires the extra
boxing and the `dyn_clone` method.
## Solution
* Rename `CalculatedSize` to `ContentSize`
* Only update `MeasureFunc`s on `CalculatedSize` changes.
* Remove the `dyn_clone` method from `Measure` and move the `Measure`
from the `ContentSize` component rather than cloning it.
* Change the measure_func field of `ContentSize` to type
`Option<taffy::node::MeasureFunc>`. Add a `set` method that wraps the
given measure appropriately.
---
## Changelog
* Renamed `CalculatedSize` to `ContentSize`.
* Replaced `upsert_leaf` with a function `update_measure` that only
updates the node's `MeasureFunc`.
* `MeasureFunc`s are only updated when the `ContentSize` changes and not
when the layout changes.
* Scale factor is no longer applied to the size values passed to the
`MeasureFunc`.
* Remove the `ContentSize` scaling in `text_system`.
* The `dyn_clone` method has been removed from the `Measure` trait.
* `Measure`s are moved from the `ContentSize` component instead of
cloning them.
* Added `set` method to `ContentSize` that replaces the `new` function.
## Migration Guide
* `CalculatedSize` has been renamed to `ContentSize`.
* The `upsert_leaf` function has been removed from `UiSurface` and
replaced with `update_measure` which updates the `MeasureFunc` without
node insertion.
* The `dyn_clone` method has been removed from the `Measure` trait.
* The new function of `CalculatedSize` has been replaced with the method
`set`.
# Objective
A lot of items in `bevy_ui` could be `FromReflect` but aren't. This
prevents users and library authors from being able to convert from a
`dyn Reflect` to one of these items.
## Solution
Derive `FromReflect` where possible. Also register the
`ReflectFromReflect` type data.
Links in the api docs are nice. I noticed that there were several places
where structs / functions and other things were referenced in the docs,
but weren't linked. I added the links where possible / logical.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
# Objective
The first query of `measure_text_system`'s `text_queries` `ParamSet`
queries for all changed `Text` meaning that non-UI `Text` entities could
be added to its queue.
## Solution
Add a `With<Node>` query filter.
---
## Changelog
changes:
* Added a `With<Node>` query filter to first query of
`measure_text_system`'s `text_queries` `ParamSet` to ensure that only UI
node entities are added to its local queue.
* Fixed comment (text is not computed on changes to style).
# Objective
If a UI node has a changed `CalculatedSize` component and either the UI
does a full update or the node also has a changed `Style` component, the
node's corresponding Taffy node will be updated twice by
`flex_node_system`.
## Solution
Add a `Without<Calculated>` query filter so that the two changed node
queries in `flex_node_system` are mutually exclusive and move the
`CalculatedSize` node updater into the else block of the full-update if
conditional.
# Objective
Split the UI overflow enum so that overflow can be set for each axis
separately.
## Solution
Change `Overflow` from an enum to a struct with `x` and `y`
`OverflowAxis` fields, where `OverflowAxis` is an enum with `Clip` and
`Visible` variants. Modify `update_clipping` to calculate clipping for
each axis separately. If only one axis is clipped, the other axis is
given infinite bounds.
<img width="642" alt="overflow"
src="https://user-images.githubusercontent.com/27962798/227592983-568cf76f-7e40-48c4-a511-43c886f5e431.PNG">
---
## Changelog
* Split the UI overflow implementation so overflow can be set for each
axis separately.
* Added the enum `OverflowAxis` with `Clip` and `Visible` variants.
* Changed `Overflow` to a struct with `x` and `y` fields of type
`OverflowAxis`.
* `Overflow` has new methods `visible()` and `hidden()` that replace its
previous `Clip` and `Visible` variants.
* Added `Overflow` helper methods `clip_x()` and `clip_y()` that return
a new `Overflow` value with the given axis clipped.
* Modified `update_clipping` so it calculates clipping for each axis
separately. If a node is only clipped on a single axis, the other axis
is given `-f32::INFINITY` to `f32::INFINITY` clipping bounds.
## Migration Guide
The `Style` property `Overflow` is now a struct with `x` and `y` fields,
that allow for per-axis overflow control.
Use these helper functions to replace the variants of `Overflow`:
* Replace `Overflow::Visible` with `Overflow::visible()`
* Replace `Overflow::Hidden` with `Overflow::clip()`
# Objective
Fixes#8415.
## Solution
I simply added the missing types to the type registry.
## Changelog
Added `#[reflect(Component]` to `bevi_ui::ui_node::ZIndex`, since it
impls `Component` and `Reflect.`
The following types have been added to the type registry:
1. `bevy_ui::ZIndex`
2. `bevy_math::Rect`
3. `bevy_text::BreakLineOn`
4. `bevy_text::Text2dBounds`
# Objective
Followup to #7779 which tweaks the actual text measurement algorithm to
be more robust.
Before:
<img width="822" alt="Screenshot 2023-04-17 at 18 12 05"
src="https://user-images.githubusercontent.com/1007307/232566858-3d3f0fd5-f3d4-400a-8371-3c2a3f541e56.png">
After:
<img width="810" alt="Screenshot 2023-04-17 at 18 41 40"
src="https://user-images.githubusercontent.com/1007307/232566919-4254cbfa-1cc3-4ea7-91ed-8ca1b759bacf.png">
(note extra space taken up in header in before example)
## Solution
- Text layout of horizontal text (currently the only kind of text we
support) is now based solely on the layout constraints in the horizontal
axis. It ignores constraints in the vertical axis and computes vertical
size based on wrapping subject to the horizontal axis constraints.
- I've also added a paragraph to the `grid` example for testing / demo
purposes.
# Objective
- Incorrectly resolved merge conflicts in
https://github.com/bevyengine/bevy/pull/8026 have caused UI text to not
render at all.
## Solution
Restore correct system schedule for text systems
# Objective
An easy way to create 2D grid layouts
## Solution
Enable the `grid` feature in Taffy and add new style types for defining
grids.
## Notes
- ~I'm having a bit of trouble getting `#[derive(Reflect)]` to work
properly. Help with that would be appreciated (EDIT: got it to compile
by ignoring the problematic fields, but this presumably can't be
merged).~ This is now fixed
- ~The alignment types now have a `Normal` variant because I couldn't
get reflect to work with `Option`.~ I've decided to stick with the
flattened variant, as it saves a level of wrapping when authoring
styles. But I've renamed the variants from `Normal` to `Default`.
- ~This currently exposes a simplified API on top of grid. In particular
the following is not currently supported:~
- ~Negative grid indices~ Now supported.
- ~Custom `end` values for grid placement (you can only use `start` and
`span`)~ Now supported
- ~`minmax()` track sizing functions~ minmax is now support through a
`GridTrack::minmax()` constructor
- ~`repeat()`~ repeat is now implemented as `RepeatedGridTrack`
- ~Documentation still needs to be improved.~ An initial pass over the
documentation has been completed.
## Screenshot
<img width="846" alt="Screenshot 2023-03-10 at 17 56 21"
src="https://user-images.githubusercontent.com/1007307/224435332-69aa9eac-123d-4856-b75d-5449d3f1d426.png">
---
## Changelog
- Support for CSS Grid layout added to `bevy_ui`
---------
Co-authored-by: Rob Parrett <robparrett@gmail.com>
Co-authored-by: Andreas Weibye <13300393+Weibye@users.noreply.github.com>
# Objective
`text_system` runs before the UI layout is calculated and the size of
the text node is determined, so it cannot correctly shape the text to
fit the layout, and has no way of determining if the text needs to be
wrapped.
The function `text_constraint` attempts to determine the size of the
node from the local size constraints in the `Style` component. It can't
be made to work, you have to compute the whole layout to get the correct
size. A simple example of where this fails completely is a text node set
to stretch to fill the empty space adjacent to a node with size
constraints set to `Val::Percent(50.)`. The text node will take up half
the space, even though its size constraints are `Val::Auto`
Also because the `text_system` queries for changes to the `Style`
component, when a style value is changed that doesn't affect the node's
geometry the text is recomputed unnecessarily.
Querying on changes to `Node` is not much better. The UI layout is
changed to fit the `CalculatedSize` of the text, so the size of the node
is changed and so the text and UI layout get recalculated multiple times
from a single change to a `Text`.
Also, the `MeasureFunc` doesn't work at all, it doesn't have enough
information to fit the text correctly and makes no attempt.
Fixes#7663, #6717, #5834, #1490,
## Solution
Split the `text_system` into two functions:
* `measure_text_system` which calculates the size constraints for the
text node and runs before `UiSystem::Flex`
* `text_system` which runs after `UiSystem::Flex` and generates the
actual text.
* Fix the `MeasureFunc` calculations.
---
Text wrapping in main:
<img width="961" alt="Capturemain"
src="https://user-images.githubusercontent.com/27962798/220425740-4fe4bf46-24fb-4685-a1cf-bc01e139e72d.PNG">
With this PR:
<img width="961" alt="captured_wrap"
src="https://user-images.githubusercontent.com/27962798/220425807-949996b0-f127-4637-9f33-56a6da944fb0.PNG">
## Changelog
* Removed the previous fields from `CalculatedSize`. `CalculatedSize`
now contains a boxed `Measure`.
* Added `measurement` module to `bevy_ui`.
* Added the method `create_text_measure` to `TextPipeline`.
* Added a new system `measure_text_system` that runs before
`UiSystem::Flex` that creates a `MeasureFunc` for the text.
* Rescheduled `text_system` to run after `UiSystem::Flex`.
* Added a trait `Measure`. A `Measure` is used to compute the size of a
UI node when the size of that node is based on its content.
* Added `ImageMeasure` and `TextMeasure` which implement `Measure`.
* Added a new component `UiImageSize` which is used by
`update_image_calculated_size_system` to track image size changes.
* Added a `UiImageSize` component to `ImageBundle`.
## Migration Guide
`ImageBundle` has a new component `UiImageSize` which contains the size
of the image bundle's texture and is updated automatically by
`update_image_calculated_size_system`
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
We don't have a constructor function for `UiRect` that sets uniform
horizontal and vertical values, even though it is a common pattern.
## Solution
Add a constructor function to `UiRect` called `axes`, that sets both
`left` and `right` to the same given horizontal value,
and sets both `top` and `bottom` to same given vertical value.
## Changelog
* Added a constructor function `axes` to `UiRect`.
# Objective
The clippy lint `type_complexity` is known not to play well with bevy.
It frequently triggers when writing complex queries, and taking the
lint's advice of using a type alias almost always just obfuscates the
code with no benefit. Because of this, this lint is currently ignored in
CI, but unfortunately it still shows up when viewing bevy code in an
IDE.
As someone who's made a fair amount of pull requests to this repo, I
will say that this issue has been a consistent thorn in my side. Since
bevy code is filled with spurious, ignorable warnings, it can be very
difficult to spot the *real* warnings that must be fixed -- most of the
time I just ignore all warnings, only to later find out that one of them
was real after I'm done when CI runs.
## Solution
Suppress this lint in all bevy crates. This was previously attempted in
#7050, but the review process ended up making it more complicated than
it needs to be and landed on a subpar solution.
The discussion in https://github.com/rust-lang/rust-clippy/pull/10571
explores some better long-term solutions to this problem. Since there is
no timeline on when these solutions may land, we should resolve this
issue in the meantime by locally suppressing these lints.
### Unresolved issues
Currently, these lints are not suppressed in our examples, since that
would require suppressing the lint in every single source file. They are
still ignored in CI.
# Objective
Make the coordinate systems of screen-space items (cursor position, UI,
viewports, etc.) consistent.
## Solution
Remove the weird double inversion of the cursor position's Y origin.
Once in bevy_winit to the bottom and then again in bevy_ui back to the
top.
This leaves the origin at the top left like it is in every other popular
app framework.
Update the `world_to_viewport`, `viewport_to_world`, and
`viewport_to_world_2d` methods to flip the Y origin (as they should
since the viewport coordinates were always relative to the top left).
## Migration Guide
`Window::cursor_position` now returns the position of the cursor
relative to the top left instead of the bottom left.
This now matches other screen-space coordinates like
`RelativeCursorPosition`, UI, and viewports.
The `world_to_viewport`, `viewport_to_world`, and `viewport_to_world_2d`
methods on `Camera` now return/take the viewport position relative to
the top left instead of the bottom left.
If you were using `world_to_viewport` to position a UI node the returned
`y` value should now be passed into the `top` field on `Style` instead
of the `bottom` field.
Note that this might shift the position of the UI node as it is now
anchored at the top.
If you were passing `Window::cursor_position` to `viewport_to_world` or
`viewport_to_world_2d` no change is necessary.
# Objective
Text glyphs that were clipped were not sized correctly because the
transform extracted from the `extract_text_uinodes` had a scaling on it
that wasn't accounted for.
fixes#8167
## Solution
Remove the scaling from the transform and multiply the size of the
glyphs by the inverse of the scale factor.
# Objective
Add helper functions to `UiImage` for creating flipped images.
## Changelog
* Added `with_flip_x` and `with_flip_y` methods to `UiImage` that return
the `UiImage` flipped along the respective axis.
# Objective
When a `CalculatedSize` component from a UI Node entity is removed, the
corresponding Taffy measure isn't removed which will mess up the layout
in confusing, unpredictable ways.
## Solution
Iterate through all the entities with removed `CalculatedSize`
components and remove the corresponding Taffy measures.
# Objective
In the
[`Text`](3442a13d2c/crates/bevy_text/src/text.rs (L18))
struct the field is named: `linebreak_behaviour`, the British spelling
of _behavior_.
**Update**, also found:
- `FileDragAndDrop::HoveredFileCancelled`
- `TouchPhase::Cancelled`
- `Touches.just_cancelled`
The majority of all spelling is in the US but when you have a lot of
contributors across the world, sometimes
spelling differences can pop up in APIs such as in this case.
For consistency, I think it would be worth a while to ensure that the
API is persistent.
Some examples:
`from_reflect.rs` has `DefaultBehavior`
TextStyle has `color` and uses the `Color` struct.
In `bevy_input/src/Touch.rs` `TouchPhase::Cancelled` and _canceled_ are
used interchangeably in the documentation
I've found that there is also the same type of discrepancies in the
documentation, though this is a low priority but is worth checking.
**Update**: I've now checked the documentation (See #8291)
## Solution
I've only renamed the inconsistencies that have breaking changes and
documentation pertaining to them. The rest of the documentation will be
changed via #8291.
Do note that the winit API is written with UK spelling, thus this may be
a cause for confusion:
`winit::event::TouchPhase::Cancelled => TouchPhase::Canceled`
`winit::event::WindowEvent::HoveredFileCancelled` -> Related to
`FileDragAndDrop::HoveredFileCanceled`
But I'm hoping to maybe outline other spelling inconsistencies in the
API, and maybe an addition to the contribution guide.
---
## Changelog
- `Text` field `linebreak_behaviour` has been renamed to
`linebreak_behavior`.
- Event `FileDragAndDrop::HoveredFileCancelled` has been renamed to
`HoveredFileCanceled`
- Function `Touches.just_cancelled` has been renamed to
`Touches.just_canceled`
- Event `TouchPhase::Cancelled` has been renamed to
`TouchPhase::Canceled`
## Migration Guide
Update where `linebreak_behaviour` is used to `linebreak_behavior`
Updated the event `FileDragAndDrop::HoveredFileCancelled` where used to
`HoveredFileCanceled`
Update `Touches.just_cancelled` where used as `Touches.just_canceled`
The event `TouchPhase::Cancelled` is now called `TouchPhase::Canceled`
# Objective
Fixes#8089.
## Solution
Splits the MainPass3dNode into 2 nodes, one for the opaque + alpha
passes and one for the transparent pass.
---
## Changelog
- Split MainPass3dNode into MainOpaquePass3dNode and
MainTransparentPass3dNode
- Combine opaque and alpha phases in MainOpaquePass3dNode into one pass
- Create `START_MAIN_PASS` and `END_MAIN_PASS` empty nodes as labels
- Main pass becomes `START_MAIN_PASS -> MAIN_OPAQUE_PASS ->
MAIN_TRANSPARENT_PASS -> END_MAIN_PASS`
## Migration Guide
Nodes that previously added edges involving `MAIN_PASS` should now add
edges to or from `START_MAIN_PASS` or `END_MAIN_PASS` respectively.
# Objective
- Currently, the render graph slots are only used to pass the
view_entity around. This introduces significant boilerplate for very
little value. Instead of using slots for this, make the view_entity part
of the `RenderGraphContext`. This also means we won't need to have
`IN_VIEW` on every node and and we'll be able to use the default impl of
`Node::input()`.
## Solution
- Add `view_entity: Option<Entity>` to the `RenderGraphContext`
- Update all nodes to use this instead of entity slot input
---
## Changelog
- Add optional `view_entity` to `RenderGraphContext`
## Migration Guide
You can now get the view_entity directly from the `RenderGraphContext`.
When implementing the Node:
```rust
// 0.10
struct FooNode;
impl FooNode {
const IN_VIEW: &'static str = "view";
}
impl Node for FooNode {
fn input(&self) -> Vec<SlotInfo> {
vec![SlotInfo::new(Self::IN_VIEW, SlotType::Entity)]
}
fn run(
&self,
graph: &mut RenderGraphContext,
// ...
) -> Result<(), NodeRunError> {
let view_entity = graph.get_input_entity(Self::IN_VIEW)?;
// ...
Ok(())
}
}
// 0.11
struct FooNode;
impl Node for FooNode {
fn run(
&self,
graph: &mut RenderGraphContext,
// ...
) -> Result<(), NodeRunError> {
let view_entity = graph.view_entity();
// ...
Ok(())
}
}
```
When adding the node to the graph, you don't need to specify a slot_edge
for the view_entity.
```rust
// 0.10
let mut graph = RenderGraph::default();
graph.add_node(FooNode::NAME, node);
let input_node_id = draw_2d_graph.set_input(vec![SlotInfo::new(
graph::input::VIEW_ENTITY,
SlotType::Entity,
)]);
graph.add_slot_edge(
input_node_id,
graph::input::VIEW_ENTITY,
FooNode::NAME,
FooNode::IN_VIEW,
);
// add_node_edge ...
// 0.11
let mut graph = RenderGraph::default();
graph.add_node(FooNode::NAME, node);
// add_node_edge ...
```
## Notes
This PR paired with #8007 will help reduce a lot of annoying boilerplate
with the render nodes. Depending on which one gets merged first. It will
require a bit of clean up work to make both compatible.
I tagged this as a breaking change, because using the old system to get
the view_entity will break things because it's not a node input slot
anymore.
## Notes for reviewers
A lot of the diffs are just removing the slots in every nodes and graph
creation. The important part is mostly in the
graph_runner/CameraDriverNode.
# Objective
Add viewport variants to `Val` that specify a percentage length based on
the size of the window.
## Solution
Add the variants `Vw`, `Vh`, `VMin` and `VMax` to `Val`.
Add a physical window size parameter to the `from_style` function and
use it to convert the viewport variants to Taffy Points values.
One issue: It isn't responsive to window resizes. So `flex_node_system`
has to do a full update every time the window size changes. Perhaps this
can be fixed with support from Taffy.
---
## Changelog
* Added `Val` viewport unit variants `Vw`, `Vh`, `VMin` and `VMax`.
* Modified `convert` module to support the new `Val` variants.
* Changed `flex_node_system` to support the new `Val` variants.
* Perform full layout update on screen resizing, to propagate the new
viewport size to all nodes.
# Objective
Add comments explaining:
* That `Val::Px` is a value in logical pixels
* That `Val::Percent` is based on the length of its parent along a
specific axis.
* How the layout algorithm determines which axis the percentage should
be based on.
# Objective
Current `Node` doc comment:
```rust
/// The size of the node as width and height in pixels
/// automatically calculated by [`super::flex::flex_node_system`]
```
It should be changed to make it clear that `Node` stores the size in logical pixels, not physical.
# Objective
Upgrade to Taffy 0.3.3
Fixes: #7712
## Solution
Upgrade to Taffy 0.3.3 with the `grid` feature disabled.
---
## Changelog
* Changed Taffy version to 0.3.3 and disabled its `grid` feature.
* Added the `Start` and `End` variants to `AlignItems`, `AlignSelf`, `AlignContent` and `JustifyContent`.
* Added the `SpaceEvenly` variant to `AlignContent`.
* Updated `from_style` for Taffy 0.3.3.
# Objective
- Fixes#7874.
- The `bevy_text` dependency is optional for `bevy_ui`, but the `accessibility` module depended on it.
## Solution
- Guard the `accessibility` module behind the `bevy_text` feature and only add the plugin when it's enabled.
# Objective
UIs created for Bevy cannot currently be made accessible. This PR aims to address that.
## Solution
Integrate AccessKit as a dependency, adding accessibility support to existing bevy_ui widgets.
## Changelog
### Added
* Integrate with and expose [AccessKit](https://accesskit.dev) for platform accessibility.
* Add `Label` for marking text specifically as a label for UI controls.
# Objective
Support the following syntax for adding systems:
```rust
App::new()
.add_system(setup.on_startup())
.add_systems((
show_menu.in_schedule(OnEnter(GameState::Paused)),
menu_ssytem.in_set(OnUpdate(GameState::Paused)),
hide_menu.in_schedule(OnExit(GameState::Paused)),
))
```
## Solution
Add the traits `IntoSystemAppConfig{s}`, which provide the extension methods necessary for configuring which schedule a system belongs to. These extension methods return `IntoSystemAppConfig{s}`, which `App::add_system{s}` uses to choose which schedule to add systems to.
---
## Changelog
+ Added the extension methods `in_schedule(label)` and `on_startup()` for configuring the schedule a system belongs to.
## Future Work
* Replace all uses of `add_startup_system` in the engine.
* Deprecate this method
# Objective
- `bevy_text` used to be "optional". the feature could be disabled, which meant that the systems were not added but `bevy_text` was still compiled because of a hard dependency in `bevy_ui`
- Running something without `bevy_text` enabled and with `bevy_ui` enabled now crashes:
```
thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', /bevy/crates/bevy_ecs/src/schedule/schedule.rs:1147:34
```
- This is because `bevy_ui` declares some of its systems in ambiguity sets with systems from `bevy_text`, which were not added if `bevy_text` is disabled
## Solution
- Make `bevy_text` completely optional
## Migration Guide
- feature `bevy_text` now completely removes `bevy_text` from the dependencies when not enabled. Enable feature `bevy_text` if you use Bevy to render text
# Objective
`TextBundle` should have a `BackgroundColor` component.
Apart from adding emphasis etc to text, adding a background color to text nodes can be extremely useful for understanding how Bevy aligns, sizes and positions text, and identifying and debugging problems.
It's easy for users to insert the `BackgroundColor` component themselves but not immediately obvious or discoverable that it's possible. A `BackgroundColor` component allows us to add a `with_background_color` helper function to `TextBundle`.
related issue: #5935
## Solution
Add a `BackgroundColor` component to `TextBundle`.
---
## Changelog
* Added a `BackgroundColor` component to `TextBundle`.
* Added a helper method `with_background_color` to `TextBundle`.
## Migration Guide
`TextBundle` now has a `BackgroundColor` component.
Use `TextBundle`'s `background_color` field or the `with_background_color` method to set a background color for text when spawning a text node, in place of manual insertion of a `BackgroundColor` component.
# Objective
Splits tone mapping from https://github.com/bevyengine/bevy/pull/6677 into a separate PR.
Address https://github.com/bevyengine/bevy/issues/2264.
Adds tone mapping options:
- None: Bypasses tonemapping for instances where users want colors output to match those set.
- Reinhard
- Reinhard Luminance: Bevy's exiting tonemapping
- [ACES](https://github.com/TheRealMJP/BakingLab/blob/master/BakingLab/ACES.hlsl) (Fitted version, based on the same implementation that Godot 4 uses) see https://github.com/bevyengine/bevy/issues/2264
- [AgX](https://github.com/sobotka/AgX)
- SomewhatBoringDisplayTransform
- TonyMcMapface
- Blender Filmic
This PR also adds support for EXR images so they can be used to compare tonemapping options with reference images.
## Migration Guide
- Tonemapping is now an enum with NONE and the various tonemappers.
- The DebandDither is now a separate component.
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
# Objective
Allow for creating pipelines that use push constants. To be able to use push constants. Fixes#4825
As of right now, trying to call `RenderPass::set_push_constants` will trigger the following error:
```
thread 'main' panicked at 'wgpu error: Validation Error
Caused by:
In a RenderPass
note: encoder = `<CommandBuffer-(0, 59, Vulkan)>`
In a set_push_constant command
provided push constant is for stage(s) VERTEX | FRAGMENT | VERTEX_FRAGMENT, however the pipeline layout has no push constant range for the stage(s) VERTEX | FRAGMENT | VERTEX_FRAGMENT
```
## Solution
Add a field push_constant_ranges to` RenderPipelineDescriptor` and `ComputePipelineDescriptor`.
This PR supersedes #4908 which now contains merge conflicts due to significant changes to `bevy_render`.
Meanwhile, this PR also made the `layout` field of `RenderPipelineDescriptor` and `ComputePipelineDescriptor` non-optional. If the user do not need to specify the bind group layouts, they can simply supply an empty vector here. No need for it to be optional.
---
## Changelog
- Add a field push_constant_ranges to RenderPipelineDescriptor and ComputePipelineDescriptor
- Made the `layout` field of RenderPipelineDescriptor and ComputePipelineDescriptor non-optional.
## Migration Guide
- Add push_constant_ranges: Vec::new() to every `RenderPipelineDescriptor` and `ComputePipelineDescriptor`
- Unwrap the optional values on the `layout` field of `RenderPipelineDescriptor` and `ComputePipelineDescriptor`. If the descriptor has no layout, supply an empty vector.
Co-authored-by: Zhixing Zhang <me@neoto.xin>
# Objective
The current doc comment for `flex-basis` states that it is "The initial size of the item", which is a bit confusing since size in Bevy is mostly used to refer to two-dimensional extents but `flex-basis` is a one-dimensional value.
It also needs to explain that:
* `flex-basis` sets the initial length of the main axis.
* Overrides `size` on the main axis.
* Obeys the `min_size` and `max_size` constraints.
# Objective
The text contained by a text node is only recomputed when its `Style` or `Text` components change, or when the scale factor changes. Not when the geometry of the text node is modified.
Make it so that any change in text node size triggers a text recomputation.
## Solution
Change `text_system` so that it queries for text nodes with changed `Node` components and recomputes their text.
---
Most users won't notice any difference but it should fix some confusing edge cases in more complicated and interactive layouts.
## Changelog
* Added `Changed<Node>` to the change detection query of `text_system`. This ensures that any change in the size of a text node will cause any text it contains to be recomputed.
# Objective
Add doc tests for the `Size` constructor functions.
Also changed the function descriptions so they explicitly state the values that elided values are given.
## Changelog
* Added doc tests for the `Size` constructor functions.
# Objective
The `size` field of `CalculatedSize` shouldn't be a `Size` as it only ever stores (unscaled) pixel values. By default its fields are `Val::Auto` but these are converted to `0`s before being sent to Taffy.
## Solution
Change the `size` field of `CalculatedSize` to a Vec2.
## Changelog
* Changed the `size` field of `CalculatedSize` to a Vec2.
* Removed the `Val` <-> `f32` conversion code for `CalculatedSize`.
## Migration Guide
* The size field of `CalculatedSize` has been changed to a `Vec2`.
# Objective
`Size::width` sets the `height` field to `Val::DEFAULT` which is `Val::Undefined`, but the default for `Size` `height` is `Val::Auto`.
`Size::height` has the same problem, but with the `width` field.
The UI examples specify numeric values in many places where they could either be elided or replaced by composition of the Flex enum properties.
related: https://github.com/bevyengine/bevy/pull/7468
fixes: https://github.com/bevyengine/bevy/issues/6498
## Solution
Change `Size::width` so it sets `height` to `Val::AUTO` and change `Size::height` so it sets `width` to `Val::AUTO`.
Added some tests so this doesn't happen again.
## Changelog
Changed `Size::width` so it sets the `height` to `Val::AUTO`.
Changed `Size::height` so it sets the `width` to `Val::AUTO`.
Added tests to `geometry.rs` for `Size` and `UiRect` to ensure correct behaviour.
Simplified the UI examples. Replaced numeric values with the Flex property enums or elided them where possible, and removed the remaining use of auto margins.
## Migration Guide
The `Size::width` constructor function now sets the `height` to `Val::Auto` instead of `Val::Undefined`.
The `Size::height` constructor function now sets the `width` to `Val::Auto` instead of `Val::Undefined`.
fixes#6799
# Objective
We should be able to reuse the `Globals` or `View` shader struct definitions from anywhere (including third party plugins) without needing to worry about defining unrelated shader defs.
Also we'd like to refactor these structs to not be repeatedly defined.
## Solution
Refactor both `Globals` and `View` into separate importable shaders.
Use the imports throughout.
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
# Objective
The current `AlignSelf` doc comments:
```rust
pub enum AlignSelf {
/// Use the value of [`AlignItems`]
Auto,
/// If the parent has [`AlignItems::Center`] only this item will be at the start
FlexStart,
/// If the parent has [`AlignItems::Center`] only this item will be at the end
FlexEnd,
/// If the parent has [`AlignItems::FlexStart`] only this item will be at the center
Center,
/// If the parent has [`AlignItems::Center`] only this item will be at the baseline
Baseline,
/// If the parent has [`AlignItems::Center`] only this item will stretch along the whole cross axis
Stretch,
}
```
Actual behaviour of `AlignSelf` in Bevy main:
<img width="642" alt="align_self" src="https://user-images.githubusercontent.com/27962798/217795178-7a82638f-118d-4474-b7f9-ca27f204731d.PNG">
The white label at the top of each column is the parent node's `AlignItems` setting.
`AlignSelf` is always applied, not (as the documentation states) only when the parent has `AlignItems::Center` or `AlignItems::FlexStart` set.
```rust
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_startup_system(setup)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2dBundle::default());
commands.spawn(NodeBundle {
style: Style {
justify_content: JustifyContent::SpaceAround,
align_items: AlignItems::Center,
size: Size::new(Val::Percent(100.), Val::Percent(100.)),
..Default::default()
},
background_color: BackgroundColor(Color::NAVY),
..Default::default()
}).with_children(|builder| {
for align_items in [
AlignItems::Baseline,
AlignItems::FlexStart,
AlignItems::Center,
AlignItems::FlexEnd,
AlignItems::Stretch,
] {
builder.spawn(NodeBundle {
style: Style {
align_items,
flex_direction: FlexDirection::Column,
justify_content: JustifyContent::SpaceBetween,
size: Size::new(Val::Px(150.), Val::Px(500.)),
..Default::default()
},
background_color: BackgroundColor(Color::DARK_GRAY),
..Default::default()
}).with_children(|builder| {
builder.spawn((
TextBundle {
text: Text::from_section(
format!("AlignItems::{align_items:?}"),
TextStyle {
font: asset_server.load("fonts/FiraSans-Regular.ttf"),
font_size: 16.0,
color: Color::BLACK,
},
),
style: Style {
align_self: AlignSelf::Stretch,
..Default::default()
},
..Default::default()
},
BackgroundColor(Color::WHITE),
));
for align_self in [
AlignSelf::Auto,
AlignSelf::FlexStart,
AlignSelf::Center,
AlignSelf::FlexEnd,
AlignSelf::Baseline,
AlignSelf::Stretch,
] {
builder.spawn((
TextBundle {
text: Text::from_section(
format!("AlignSelf::{align_self:?}"),
TextStyle {
font: asset_server.load("fonts/FiraSans-Regular.ttf"),
font_size: 16.0,
color: Color::WHITE,
},
),
style: Style {
align_self,
..Default::default()
},
..Default::default()
},
BackgroundColor(Color::BLACK),
));
}
});
}
});
}
```
# Objective
Fix#7377Fix#7513
## Solution
Record the changes made to the Bevy `Window` from `winit` as 'canon' to avoid Bevy sending those changes back to `winit` again, causing a feedback loop.
## Changelog
* Removed `ModifiesWindows` system label.
Neither `despawn_window` nor `changed_window` actually modify the `Window` component so all the `.after(ModifiesWindows)` shouldn't be necessary.
* Moved `changed_window` and `despawn_window` systems to `CoreStage::Last` to avoid systems making changes to the `Window` between `changed_window` and the end of the frame as they would be ignored.
## Migration Guide
The `ModifiesWindows` system label was removed.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267.
"Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365).
## Solution
This adds "base sets" as a variant of `SystemSet`:
A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive:
```rust
#[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)]
#[system_set(base)]
enum MyBaseSet {
A,
B,
}
```
**Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build.
**Base sets cannot belong to other sets**: this is where the word "base" comes from
Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set.
```rust
app.add_system(foo.in_base_set(MyBaseSet::A))
// X must be a normal set ... base sets cannot be added to base sets
.configure_set(X.in_base_set(MyBaseSet::A))
```
Base sets can still be configured like normal sets:
```rust
app.add_system(MyBaseSet::B.after(MyBaseSet::Ap))
```
The primary use case for base sets is enabling a "default base set":
```rust
schedule.set_default_base_set(CoreSet::Update)
// this will belong to CoreSet::Update by default
.add_system(foo)
// this will override the default base set with PostUpdate
.add_system(bar.in_base_set(CoreSet::PostUpdate))
```
This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides.
---
## Changelog
- Added "base sets" and ported CoreSet to use them.
## Migration Guide
TODO
Huge thanks to @maniwani, @devil-ira, @hymm, @cart, @superdump and @jakobhellermann for the help with this PR.
# Objective
- Followup #6587.
- Minimal integration for the Stageless Scheduling RFC: https://github.com/bevyengine/rfcs/pull/45
## Solution
- [x] Remove old scheduling module
- [x] Migrate new methods to no longer use extension methods
- [x] Fix compiler errors
- [x] Fix benchmarks
- [x] Fix examples
- [x] Fix docs
- [x] Fix tests
## Changelog
### Added
- a large number of methods on `App` to work with schedules ergonomically
- the `CoreSchedule` enum
- `App::add_extract_system` via the `RenderingAppExtension` trait extension method
- the private `prepare_view_uniforms` system now has a public system set for scheduling purposes, called `ViewSet::PrepareUniforms`
### Removed
- stages, and all code that mentions stages
- states have been dramatically simplified, and no longer use a stack
- `RunCriteriaLabel`
- `AsSystemLabel` trait
- `on_hierarchy_reports_enabled` run criteria (now just uses an ad hoc resource checking run condition)
- systems in `RenderSet/Stage::Extract` no longer warn when they do not read data from the main world
- `RunCriteriaLabel`
- `transform_propagate_system_set`: this was a nonstandard pattern that didn't actually provide enough control. The systems are already `pub`: the docs have been updated to ensure that the third-party usage is clear.
### Changed
- `System::default_labels` is now `System::default_system_sets`.
- `App::add_default_labels` is now `App::add_default_sets`
- `CoreStage` and `StartupStage` enums are now `CoreSet` and `StartupSet`
- `App::add_system_set` was renamed to `App::add_systems`
- The `StartupSchedule` label is now defined as part of the `CoreSchedules` enum
- `.label(SystemLabel)` is now referred to as `.in_set(SystemSet)`
- `SystemLabel` trait was replaced by `SystemSet`
- `SystemTypeIdLabel<T>` was replaced by `SystemSetType<T>`
- The `ReportHierarchyIssue` resource now has a public constructor (`new`), and implements `PartialEq`
- Fixed time steps now use a schedule (`CoreSchedule::FixedTimeStep`) rather than a run criteria.
- Adding rendering extraction systems now panics rather than silently failing if no subapp with the `RenderApp` label is found.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied.
- `SceneSpawnerSystem` now runs under `CoreSet::Update`, rather than `CoreStage::PreUpdate.at_end()`.
- `bevy_pbr::add_clusters` is no longer an exclusive system
- the top level `bevy_ecs::schedule` module was replaced with `bevy_ecs::scheduling`
- `tick_global_task_pools_on_main_thread` is no longer run as an exclusive system. Instead, it has been replaced by `tick_global_task_pools`, which uses a `NonSend` resource to force running on the main thread.
## Migration Guide
- Calls to `.label(MyLabel)` should be replaced with `.in_set(MySet)`
- Stages have been removed. Replace these with system sets, and then add command flushes using the `apply_system_buffers` exclusive system where needed.
- The `CoreStage`, `StartupStage, `RenderStage` and `AssetStage` enums have been replaced with `CoreSet`, `StartupSet, `RenderSet` and `AssetSet`. The same scheduling guarantees have been preserved.
- Systems are no longer added to `CoreSet::Update` by default. Add systems manually if this behavior is needed, although you should consider adding your game logic systems to `CoreSchedule::FixedTimestep` instead for more reliable framerate-independent behavior.
- Similarly, startup systems are no longer part of `StartupSet::Startup` by default. In most cases, this won't matter to you.
- For example, `add_system_to_stage(CoreStage::PostUpdate, my_system)` should be replaced with
- `add_system(my_system.in_set(CoreSet::PostUpdate)`
- When testing systems or otherwise running them in a headless fashion, simply construct and run a schedule using `Schedule::new()` and `World::run_schedule` rather than constructing stages
- Run criteria have been renamed to run conditions. These can now be combined with each other and with states.
- Looping run criteria and state stacks have been removed. Use an exclusive system that runs a schedule if you need this level of control over system control flow.
- For app-level control flow over which schedules get run when (such as for rollback networking), create your own schedule and insert it under the `CoreSchedule::Outer` label.
- Fixed timesteps are now evaluated in a schedule, rather than controlled via run criteria. The `run_fixed_timestep` system runs this schedule between `CoreSet::First` and `CoreSet::PreUpdate` by default.
- Command flush points introduced by `AssetStage` have been removed. If you were relying on these, add them back manually.
- Adding extract systems is now typically done directly on the main app. Make sure the `RenderingAppExtension` trait is in scope, then call `app.add_extract_system(my_system)`.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. You may need to order your movement systems to occur before this system in order to avoid system order ambiguities in culling behavior.
- the `RenderLabel` `AppLabel` was renamed to `RenderApp` for clarity
- `App::add_state` now takes 0 arguments: the starting state is set based on the `Default` impl.
- Instead of creating `SystemSet` containers for systems that run in stages, simply use `.on_enter::<State::Variant>()` or its `on_exit` or `on_update` siblings.
- `SystemLabel` derives should be replaced with `SystemSet`. You will also need to add the `Debug`, `PartialEq`, `Eq`, and `Hash` traits to satisfy the new trait bounds.
- `with_run_criteria` has been renamed to `run_if`. Run criteria have been renamed to run conditions for clarity, and should now simply return a bool.
- States have been dramatically simplified: there is no longer a "state stack". To queue a transition to the next state, call `NextState::set`
## TODO
- [x] remove dead methods on App and World
- [x] add `App::add_system_to_schedule` and `App::add_systems_to_schedule`
- [x] avoid adding the default system set at inappropriate times
- [x] remove any accidental cycles in the default plugins schedule
- [x] migrate benchmarks
- [x] expose explicit labels for the built-in command flush points
- [x] migrate engine code
- [x] remove all mentions of stages from the docs
- [x] verify docs for States
- [x] fix uses of exclusive systems that use .end / .at_start / .before_commands
- [x] migrate RenderStage and AssetStage
- [x] migrate examples
- [x] ensure that transform propagation is exported in a sufficiently public way (the systems are already pub)
- [x] ensure that on_enter schedules are run at least once before the main app
- [x] re-enable opt-in to execution order ambiguities
- [x] revert change to `update_bounds` to ensure it runs in `PostUpdate`
- [x] test all examples
- [x] unbreak directional lights
- [x] unbreak shadows (see 3d_scene, 3d_shape, lighting, transparaency_3d examples)
- [x] game menu example shows loading screen and menu simultaneously
- [x] display settings menu is a blank screen
- [x] `without_winit` example panics
- [x] ensure all tests pass
- [x] SubApp doc test fails
- [x] runs_spawn_local tasks fails
- [x] [Fix panic_when_hierachy_cycle test hanging](https://github.com/alice-i-cecile/bevy/pull/120)
## Points of Difficulty and Controversy
**Reviewers, please give feedback on these and look closely**
1. Default sets, from the RFC, have been removed. These added a tremendous amount of implicit complexity and result in hard to debug scheduling errors. They're going to be tackled in the form of "base sets" by @cart in a followup.
2. The outer schedule controls which schedule is run when `App::update` is called.
3. I implemented `Label for `Box<dyn Label>` for our label types. This enables us to store schedule labels in concrete form, and then later run them. I ran into the same set of problems when working with one-shot systems. We've previously investigated this pattern in depth, and it does not appear to lead to extra indirection with nested boxes.
4. `SubApp::update` simply runs the default schedule once. This sucks, but this whole API is incomplete and this was the minimal changeset.
5. `time_system` and `tick_global_task_pools_on_main_thread` no longer use exclusive systems to attempt to force scheduling order
6. Implemetnation strategy for fixed timesteps
7. `AssetStage` was migrated to `AssetSet` without reintroducing command flush points. These did not appear to be used, and it's nice to remove these bottlenecks.
8. Migration of `bevy_render/lib.rs` and pipelined rendering. The logic here is unusually tricky, as we have complex scheduling requirements.
## Future Work (ideally before 0.10)
- Rename schedule_v3 module to schedule or scheduling
- Add a derive macro to states, and likely a `EnumIter` trait of some form
- Figure out what exactly to do with the "systems added should basically work by default" problem
- Improve ergonomics for working with fixed timesteps and states
- Polish FixedTime API to match Time
- Rebase and merge #7415
- Resolve all internal ambiguities (blocked on better tools, especially #7442)
- Add "base sets" to replace the removed default sets.
# Objective
Fixes#7476. UI scale was being incorrectly ignored when a primary window exists.
## Solution
Always take into account UI scale, regardless of whether a primary window exists.
Tested locally on @forbjok 's minimal repro project https://github.com/forbjok/bevy_ui_repro with this patch, and the issue is fixed on my machine.
The `DoubleEndedIterator` impls produce incorrect results on subsequent calls to `iter()` if the iterator is only partially consumed.
The following code shows what happens
```rust
fn next_back_is_bad() {
let mut events = Events::<TestEvent>::default();
events.send(TestEvent { i: 0 });
events.send(TestEvent { i: 1 });
events.send(TestEvent { i: 2 });
let mut reader = events.get_reader();
let mut iter = reader.iter(&events);
assert_eq!(iter.next_back(), Some(&TestEvent { i: 2 }));
assert_eq!(iter.next(), Some(&TestEvent { i: 0 }));
let mut iter = reader.iter(&events);
// `i: 2` event is returned twice! The `i: 1` event is missed.
assert_eq!(iter.next(), Some(&TestEvent { i: 2 }));
assert_eq!(iter.next(), None);
}
```
I don't think this can be fixed without adding some very convoluted bookkeeping.
## Migration Guide
`ManualEventIterator` and `ManualEventIteratorWithId` are no longer `DoubleEndedIterator`s.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
Removal events are unwieldy and require some knowledge of when to put systems that need to catch events for them, it is very easy to end up missing one and end up with memory leak-ish issues where you don't clean up after yourself.
## Solution
Consolidate removals with the benefits of `Events<...>` (such as double buffering and per system ticks for reading the events) and reduce the special casing of it, ideally I was hoping to move the removals to a `Resource` in the world, but that seems a bit more rough to implement/maintain because of double mutable borrowing issues.
This doesn't go the full length of change detection esque removal detection a la https://github.com/bevyengine/rfcs/pull/44.
Just tries to make the current workflow a bit more user friendly so detecting removals isn't such a scheduling nightmare.
---
## Changelog
- RemovedComponents<T> is now backed by an `Events<Entity>` for the benefits of double buffering.
## Migration Guide
- Add a `mut` for `removed: RemovedComponents<T>` since we are now modifying an event reader internally.
- Iterating over removed components now requires `&mut removed_components` or `removed_components.iter()` instead of `&removed_components`.
# Objective
In CSS Flexbox width and height are auto by default, whereas in Bevy their default is `Size::Undefined`.
This means that, unlike in CSS, if you elide a height or width value for a node it will be given zero length (unless it has an explicitly sized child node). This has misled users into falsely assuming that they have to explicitly set a value for both height and width all the time.
relevant issue: #7120
## Solution
Change the `Size` `width` and `height` default values to `Val::Auto`
## Changelog
* Changed the `Size` `width` and `height` default values to `Val::Auto`
## Migration Guide
The default values for `Size` `width` and `height` have been changed from `Val::Undefined` to `Val::Auto`.
It's unlikely to cause any issues with existing code.
## Objective
A common easy to miss mistake is to write something like:
``` rust
Size::new(Val::Percent(100.), Val::Px(100.));
```
`UiRect` has the `left`, `right`, `all`, `vertical`, etc constructor functions, `Size` is used a lot more frequently but lacks anything similar.
## Solution
Implement `all`, `width` and `height` functions for `Size`.
## Changelog
* Added `all`, `width` and `height` functions to `Size`.
# Problem
The field is called `background_color` but it is also used to hold the colors of text glyphs and images.
It's mildly confusing and longer to type than just `color`.
## Solution
Rename `background_color` to `color`.
## Changelog
* Renamed the `background_color` field of `ExtractedUiNode` to `color`.
## Migration Guide
* The `background_color` field of `ExtractedUiNode` is now named `color`.
## Objective
Remove `QueuedText`.
`QueuedText` isn't useful. It's exposed in the `bevy_ui` public interface but can't be used for anything because its `entities` field is private.
## Solution
Remove the `QueuedText` struct and use a `Local<Vec<Entity>` in its place.
## Changelog
* Removed `QueuedText`
# Objective
In simple cases we might want to derive the `ExtractComponent` trait.
This adds symmetry to the existing `ExtractResource` derive.
## Solution
Add an implementation of `#[derive(ExtractComponent)]`.
The implementation is adapted from the existing `ExtractResource` derive macro.
Additionally, there is an attribute called `extract_component_filter`. This allows specifying a query filter type used when extracting.
If not specified, no filter (equal to `()`) is used.
So:
```rust
#[derive(Component, Clone, ExtractComponent)]
#[extract_component_filter(With<Fuel>)]
pub struct Car {
pub wheels: usize,
}
```
would expand to (a bit cleaned up here):
```rust
impl ExtractComponent for Car
{
type Query = &'static Self;
type Filter = With<Fuel>;
type Out = Self;
fn extract_component(item: QueryItem<'_, Self::Query>) -> Option<Self::Out> {
Some(item.clone())
}
}
```
---
## Changelog
- Added the ability to `#[derive(ExtractComponent)]` with an optional filter.
Co-authored-by: Robert Swain <robert.swain@gmail.com>
# Objective
Implements cascaded shadow maps for directional lights, which produces better quality shadows without needing excessively large shadow maps.
Fixes#3629
Before
After
## Solution
Rather than rendering a single shadow map for directional light, the view frustum is divided into a series of cascades, each of which gets its own shadow map. The correct cascade is then sampled for shadow determination.
---
## Changelog
Directional lights now use cascaded shadow maps for improved shadow quality.
## Migration Guide
You no longer have to manually specify a `shadow_projection` for a directional light, and these settings should be removed. If customization of how cascaded shadow maps work is desired, modify the `CascadeShadowConfig` component instead.
