# Objective
- Resolves#10853
## Solution
- ~~Changed the name of `Input` struct to `PressableInput`.~~
- Changed the name of `Input` struct to `ButtonInput`.
## Migration Guide
- Breaking Change: Users need to rename `Input` to `ButtonInput` in
their projects.
# Objective
The name `TextAlignment` is really deceptive and almost every new user
gets confused about the differences between aligning text with
`TextAlignment`, aligning text with `Style` and aligning text with
anchor (when using `Text2d`).
## Solution
* Rename `TextAlignment` to `JustifyText`. The associated helper methods
are also renamed.
* Improve the doc comments for text explaining explicitly how the
`JustifyText` component affects the arrangement of text.
* Add some extra cases to the `text_debug` example that demonstate the
differences between alignment using `JustifyText` and alignment using
`Style`.
<img width="757" alt="text_debug_2"
src="https://github.com/bevyengine/bevy/assets/27962798/9d53e647-93f9-4bc7-8a20-0d9f783304d2">
---
## Changelog
* `TextAlignment` has been renamed to `JustifyText`
* `TextBundle::with_text_alignment` has been renamed to
`TextBundle::with_text_justify`
* `Text::with_alignment` has been renamed to `Text::with_justify`
* The `text_alignment` field of `TextMeasureInfo` has been renamed to
`justification`
## Migration Guide
* `TextAlignment` has been renamed to `JustifyText`
* `TextBundle::with_text_alignment` has been renamed to
`TextBundle::with_text_justify`
* `Text::with_alignment` has been renamed to `Text::with_justify`
* The `text_alignment` field of `TextMeasureInfo` has been renamed to
`justification`
# Objective
Problems:
* The clipped, non-visible regions of UI nodes are interactive.
* `RelativeCursorPostion` is set relative to the visible part of the
node. It should be relative to the whole node.
* The `RelativeCursorPostion::mouse_over` method returns `true` when the
mouse is over a clipped part of a node.
fixes#10470
## Solution
Intersect a node's bounding rect with its clipping rect before checking
if it contains the cursor.
Added the field `normalized_visible_node_rect` to
`RelativeCursorPosition`. This is set to the bounds of the unclipped
area of the node rect by `ui_focus_system` expressed in normalized
coordinates relative to the entire node.
Instead of checking if the normalized cursor position lies within a unit
square, it instead checks if it is contained by
`normalized_visible_node_rect`.
Added outlines to the `overflow` example that appear when the cursor is
over the visible part of the images, but not the clipped area.
---
## Changelog
* `ui_focus_system` intersects a node's bounding rect with its clipping
rect before checking if mouse over.
* Added the field `normalized_visible_node_rect` to
`RelativeCursorPosition`. This is set to the bounds of the unclipped
area of the node rect by `ui_focus_system` expressed in normalized
coordinates relative to the entire node.
* `RelativeCursorPostion` is calculated relative to the whole node's
position and size, not only the visible part.
* `RelativeCursorPosition::mouse_over` only returns true when the mouse
is over an unclipped region of the UI node.
* Removed the `Deref` and `DerefMut` derives from
`RelativeCursorPosition` as it is no longer a single field struct.
* Added some outlines to the `overflow` example that respond to
`Interaction` changes.
## Migration Guide
The clipped areas of UI nodes are no longer interactive.
`RelativeCursorPostion` is now calculated relative to the whole node's
position and size, not only the visible part. Its `mouse_over` method
only returns true when the cursor is over an unclipped part of the node.
`RelativeCursorPosition` no longer implements `Deref` and `DerefMut`.
# Objective
- Fix adding `#![allow(clippy::type_complexity)]` everywhere. like #9796
## Solution
- Use the new [lints] table that will land in 1.74
(https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#lints)
- inherit lint to the workspace, crates and examples.
```
[lints]
workspace = true
```
## Changelog
- Bump rust version to 1.74
- Enable lints table for the workspace
```toml
[workspace.lints.clippy]
type_complexity = "allow"
```
- Allow type complexity for all crates and examples
```toml
[lints]
workspace = true
```
---------
Co-authored-by: Martín Maita <47983254+mnmaita@users.noreply.github.com>
# Objective
Closes#10319
## Changelog
* Added a new `Color::rgba_from_array([f32; 4]) -> Color` method.
* Added a new `Color::rgb_from_array([f32; 3]) -> Color` method.
* Added a new `Color::rgba_linear_from_array([f32; 4]) -> Color` method.
* Added a new `Color::rgb_linear_from_array([f32; 3]) -> Color` method.
* Added a new `Color::hsla_from_array([f32; 4]) -> Color` method.
* Added a new `Color::hsl_from_array([f32; 3]) -> Color` method.
* Added a new `Color::lcha_from_array([f32; 4]) -> Color` method.
* Added a new `Color::lch_from_array([f32; 3]) -> Color` method.
* Added a new `Color::rgba_to_vec4(&self) -> Vec4` method.
* Added a new `Color::rgba_to_array(&self) -> [f32; 4]` method.
* Added a new `Color::rgb_to_vec3(&self) -> Vec3` method.
* Added a new `Color::rgb_to_array(&self) -> [f32; 3]` method.
* Added a new `Color::rgba_linear_to_vec4(&self) -> Vec4` method.
* Added a new `Color::rgba_linear_to_array(&self) -> [f32; 4]` method.
* Added a new `Color::rgb_linear_to_vec3(&self) -> Vec3` method.
* Added a new `Color::rgb_linear_to_array(&self) -> [f32; 3]` method.
* Added a new `Color::hsla_to_vec4(&self) -> Vec4` method.
* Added a new `Color::hsla_to_array(&self) -> [f32; 4]` method.
* Added a new `Color::hsl_to_vec3(&self) -> Vec3` method.
* Added a new `Color::hsl_to_array(&self) -> [f32; 3]` method.
* Added a new `Color::lcha_to_vec4(&self) -> Vec4` method.
* Added a new `Color::lcha_to_array(&self) -> [f32; 4]` method.
* Added a new `Color::lch_to_vec3(&self) -> Vec3` method.
* Added a new `Color::lch_to_array(&self) -> [f32; 3]` method.
## Migration Guide
`Color::from(Vec4)` is now `Color::rgba_from_array(impl Into<[f32; 4]>)`
`Vec4::from(Color)` is now `Color::rgba_to_vec4(&self)`
Before:
```rust
let color_vec4 = Vec4::new(0.5, 0.5, 0.5);
let color_from_vec4 = Color::from(color_vec4);
let color_array = [0.5, 0.5, 0.5];
let color_from_array = Color::from(color_array);
```
After:
```rust
let color_vec4 = Vec4::new(0.5, 0.5, 0.5);
let color_from_vec4 = Color::rgba_from_array(color_vec4);
let color_array = [0.5, 0.5, 0.5];
let color_from_array = Color::rgba_from_array(color_array);
```
# Objective
Fixes#10439
`Timer::percent()` and `Timer::percent_left()` return values in the
range of 0.0 to 1.0, even though their names contain "percent".
These functions should be renamed for clarity.
## Solution
- Rename `Timer::percent()` to `Timer::fraction()`
- Rename `Timer::percent_left()` to `Timer::fraction_remaining()`
---
## Changelog
### Changed
- Renamed `Timer::percent()` to `Timer::fraction()`
- Renamed `Timer::percent_left()` to `Timer::fraction_remaining()`
## Migration Guide
- `Timer::percent()` has been renamed to `Timer::fraction()`
- `Timer::percent_left()` has been renamed to
`Timer::fraction_remaining()`
When `cargo doc -Zunstable-options -Zrustdoc-scrape-examples` (trying to
figure out why it doesn't work with bevy), I had the following warnings:
```
warning: unresolved link to `Quad`
--> examples/2d/mesh2d.rs:1:66
|
1 | //! Shows how to render a polygonal [`Mesh`], generated from a [`Quad`] primitive, in a 2D scene.
| ^^^^ no item named `Quad` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "mesh2d") generated 1 warning
warning: unresolved link to `update_weights`
--> examples/animation/morph_targets.rs:6:17
|
6 | //! See the [`update_weights`] system for details.
| ^^^^^^^^^^^^^^ no item named `update_weights` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: public documentation for `morph_targets` links to private item `name_morphs`
--> examples/animation/morph_targets.rs:7:43
|
7 | //! - How to read morph target names in [`name_morphs`].
| ^^^^^^^^^^^ this item is private
|
= note: this link will resolve properly if you pass `--document-private-items`
= note: `#[warn(rustdoc::private_intra_doc_links)]` on by default
warning: public documentation for `morph_targets` links to private item `setup_animations`
--> examples/animation/morph_targets.rs:8:48
|
8 | //! - How to play morph target animations in [`setup_animations`].
| ^^^^^^^^^^^^^^^^ this item is private
|
= note: this link will resolve properly if you pass `--document-private-items`
warning: `bevy` (example "morph_targets") generated 3 warnings
warning: unresolved link to `Quad`
--> examples/2d/mesh2d_vertex_color_texture.rs:1:66
|
1 | //! Shows how to render a polygonal [`Mesh`], generated from a [`Quad`] primitive, in a 2D scene.
| ^^^^ no item named `Quad` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "mesh2d_vertex_color_texture") generated 1 warning
warning: unresolved link to `UIScale`
--> examples/ui/ui_scaling.rs:1:36
|
1 | //! This example illustrates the [`UIScale`] resource from `bevy_ui`.
| ^^^^^^^ no item named `UIScale` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "ui_scaling") generated 1 warning
warning: unresolved link to `dependencies`
--> examples/app/headless.rs:5:6
|
5 | //! [dependencies]
| ^^^^^^^^^^^^ no item named `dependencies` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "headless") generated 1 warning
warning: unresolved link to `Material2d`
--> examples/2d/mesh2d_manual.rs:3:26
|
3 | //! It doesn't use the [`Material2d`] abstraction, but changes the vertex buffer to include verte...
| ^^^^^^^^^^ no item named `Material2d` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "mesh2d_manual") generated 1 warning
```
# Objective
- Changes the default clear color to match the code block color on
Bevy's website.
## Solution
- Changed the clear color, updated text in examples to ensure adequate
contrast. Inconsistent usage of white text color set to use the default
color instead, which is already white.
- Additionally, updated the `3d_scene` example to make it look a bit
better, and use bevy's branding colors.
# Objective
Add support for drawing outlines outside the borders of UI nodes.
## Solution
Add a new `Outline` component with `width`, `offset` and `color` fields.
Added `outline_width` and `outline_offset` fields to `Node`. This is set
after layout recomputation by the `resolve_outlines_system`.
Properties of outlines:
* Unlike borders, outlines have to be the same width on each edge.
* Outlines do not occupy any space in the layout.
* The `Outline` component won't be added to any of the UI node bundles,
it needs to be inserted separately.
* Outlines are drawn outside the node's border, so they are clipped
using the clipping rect of their entity's parent UI node (if it exists).
* `Val::Percent` outline widths are resolved based on the width of the
outlined UI node.
* The offset of the `Outline` adds space between an outline and the edge
of its node.
I was leaning towards adding an `outline` field to `Style` but a
separate component seems more efficient for queries and change
detection. The `Outline` component isn't added to bundles for the same
reason.
---
## Examples
* This image is from the `borders` example from the Bevy UI examples but
modified to include outlines. The UI nodes are the dark red rectangles,
the bright red rectangles are borders and the white lines offset from
each node are the outlines. The yellow rectangles are separate nodes
contained with the dark red nodes:
<img width="406" alt="outlines"
src="https://github.com/bevyengine/bevy/assets/27962798/4e6f315a-019f-42a4-94ee-cca8e684d64a">
* This is from the same example but using a branch that implements
border-radius. Here the the outlines are in orange and there is no
offset applied. I broke the borders implementation somehow during the
merge, which is why some of the borders from the first screenshot are
missing 😅. The outlines work nicely though (as long as you
can forgive the lack of anti-aliasing):
---
## Notes
As I explained above, I don't think the `Outline` component should be
added to UI node bundles. We can have helper functions though, perhaps
something as simple as:
```rust
impl NodeBundle {
pub fn with_outline(self, outline: Outline) -> (Self, Outline) {
(self, outline)
}
}
```
I didn't include anything like this as I wanted to keep the PR's scope
as narrow as possible. Maybe `with_outline` should be in a trait that we
implement for each UI node bundle.
---
## Changelog
Added support for outlines to Bevy UI.
* The `Outline` component adds an outline to a UI node.
* The `outline_width` field added to `Node` holds the resolved width of
the outline, which is set by the `resolve_outlines_system` after layout
recomputation.
* Outlines are drawn by the system `extract_uinode_outlines`.
# Objective
- See fewer warnings when running `cargo clippy` locally.
## Solution
- allow `clippy::type_complexity` in more places, which also signals to
users they should do the same.
# 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
- Compile all targets without warnings about unused doc comments.
## Solution
- Turn unused doc comments into regular comments. Doc comments aren't
supported on expressions, so they can just be regular comments.
# 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>
# 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
The `viewport_debug` example opens a window that is physically very
large. Probably larger than the screen for the majority of machines.
## Solution
Remove the custom resolution and adjust the pixel coordinates so that
everything lines up.
At the default resolution, everything is still whole numbers even
without adjusting the viewport coordinates.
# 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
- 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
Fix a few issues with some of the examples:
* Root UI nodes have an implicit parent with `FlexDirection::Row` and
`AlignItems::Stretch` set. Only a width constraint is needed to fill the
viewport. Specifying ```height: Val::Percent(100.)``` is unnecessary and
can cause confusing overflow behaviour.
* The default for position and size constraint properties is
`Val::Auto`. Setting `left: Val::Auto`, `max_height: Val::Auto`, etc
does nothing.
## Solution
Delete those lines. There should be no observable differences in the
behaviours of any of the examples.
Also changed a padding setting in the `flex_layout` example to use the
`axes` helper function.
# 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
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
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
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`.
`Style` flattened `size`, `min_size` and `max_size` to its root struct,
causing compilation errors.
I uncommented the code to avoid further silent error not caught by CI,
but hid the view to keep the same behaviour.
# 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
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
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
The AccessKit PR removed the loading of the image logo from the UI
example.
It also added some alt text with `TextStyle::default()` as a child of
the logo image node.
If you give an image node a child, then its size is no longer determined
by the measurefunc that preserves its aspect ratio. Instead, its width
and height are determined by the constraints set on the node and the
size of the contents of the node. In this case, the image node is set to
have a width of 500 with no constraints on its height. So it looks at
its child node to determine what height it should take. Because the
child has `TextStyle::default` it allocates no space for the text, the
height of the image node is set to zero and the logo isn't drawn.
Fixes#8805
## Solution
Load the image, and set min_size and max_size constraints of 500 by 125
pixels.
# Objective
Be consistent with `Resource`s and `Components` and have `Event` types
be more self-documenting.
Although not susceptible to accidentally using a function instead of a
value due to `Event`s only being initialized by their type, much of the
same reasoning for removing the blanket impl on `Resource` also applies
here.
* Not immediately obvious if a type is intended to be an event
* Prevent invisible conflicts if the same third-party or primitive types
are used as events
* Allows for further extensions (e.g. opt-in warning for missed events)
## Solution
Remove the blanket impl for the `Event` trait. Add a derive macro for
it.
---
## Changelog
- `Event` is no longer implemented for all applicable types. Add the
`#[derive(Event)]` macro for events.
## Migration Guide
* Add the `#[derive(Event)]` macro for events. Third-party types used as
events should be wrapped in a newtype.
# Objective
I was trying to add some `Diagnostics` to have a better break down of
performance but I noticed that the current implementation uses a
`ResMut` which forces the functions to all run sequentially whereas
before they could run in parallel. This created too great a performance
penalty to be usable.
## Solution
This PR reworks how the diagnostics work with a couple of breaking
changes. The idea is to change how `Diagnostics` works by changing it to
a `SystemParam`. This allows us to hold a `Deferred` buffer of
measurements that can be applied later, avoiding the need for multiple
mutable references to the hashmap. This means we can run systems that
write diagnostic measurements in parallel.
Firstly, we rename the old `Diagnostics` to `DiagnosticsStore`. This
clears up the original name for the new interface while allowing us to
preserve more closely the original API.
Then we create a new `Diagnostics` struct which implements `SystemParam`
and contains a deferred `SystemBuffer`. This can be used very similar to
the old `Diagnostics` for writing new measurements.
```rust
fn system(diagnostics: ResMut<Diagnostics>) { diagnostics.new_measurement(ID, || 10.0)}
// changes to
fn system(mut diagnostics: Diagnostics) { diagnostics.new_measurement(ID, || 10.0)}
```
For reading the diagnostics, the user needs to change from `Diagnostics`
to `DiagnosticsStore` but otherwise the function calls are the same.
Finally, we add a new method to the `App` for registering diagnostics.
This replaces the old method of creating a startup system and adding it
manually.
Testing it, this PR does indeed allow Diagnostic systems to be run in
parallel.
## Changelog
- Change `Diagnostics` to implement `SystemParam` which allows
diagnostic systems to run in parallel.
## Migration Guide
- Register `Diagnostic`'s using the new
`app.register_diagnostic(Diagnostic::new(DIAGNOSTIC_ID,
"diagnostic_name", 10));`
- In systems for writing new measurements, change `mut diagnostics:
ResMut<Diagnostics>` to `mut diagnostics: Diagnostics` to allow the
systems to run in parallel.
- In systems for reading measurements, change `diagnostics:
Res<Diagnostics>` to `diagnostics: Res<DiagnosticsStore>`.
# Objective
- fix clippy lints early to make sure CI doesn't break when they get
promoted to stable
- have a noise-free `clippy` experience for nightly users
## Solution
- `cargo clippy --fix`
- replace `filter_map(|x| x.ok())` with `map_while(|x| x.ok())` to fix
potential infinite loop in case of IO error
# 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>
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
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
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
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>
Fixes issue mentioned in PR #8285.
_Note: By mistake, this is currently dependent on #8285_
# Objective
Ensure consistency in the spelling of the documentation.
Exceptions:
`crates/bevy_mikktspace/src/generated.rs` - Has not been changed from
licence to license as it is part of a licensing agreement.
Maybe for further consistency,
https://github.com/bevyengine/bevy-website should also be given a look.
## Solution
### Changed the spelling of the current words (UK/CN/AU -> US) :
cancelled -> canceled (Breaking API changes in #8285)
behaviour -> behavior (Breaking API changes in #8285)
neighbour -> neighbor
grey -> gray
recognise -> recognize
centre -> center
metres -> meters
colour -> color
### ~~Update [`engine_style_guide.md`]~~ Moved to #8324
---
## Changelog
Changed UK spellings in documentation to US
## Migration Guide
Non-breaking changes*
\* If merged after #8285
# Objective
- Add a new example that helps debug different UI overflow scenarios
- This example tests the clipping behavior for images and text when the
node is moved, scaled or rotated.
## Solution
- Add a new `overflow_debug` example
# Preview
**Note:** Only top-left is working properly right now.
https://user-images.githubusercontent.com/188612/227629093-26c94c67-1781-437d-8410-e854b6f1adc1.mp4
---
Related #8095, #8167
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
