e9daac4f11
176 Commits
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7063c86ed4
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Fix some typos (#9934)
# Objective To celebrate the turning of the seasons, I took a small walk through the codebase guided by the "[code spell checker](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker)" VS Code extension and fixed a few typos. |
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462d2ff238
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Move Val into geometry (#9818)
# Objective `Val`'s natural place is in the `geometry` module with `UiRect`, not in `ui_node` with the components. ## Solution Move `Val` into `geometry`. |
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0aa079fcf6
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Fix doc comments for align items (#9739)
# Objective One-line fix to a doc-comment for AlignItems Co-authored-by: Charles Bournhonesque <cbournhonesque@snapchat.com> |
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5eb292dc10
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Bevy Asset V2 (#8624)
# 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> |
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64dcaf002b
|
Rename Val evaluate to resolve and implement viewport variant support (#9568)
# 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` |
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9f27f011c1
|
Remove Val 's try_* arithmetic methods (#9609)
# Objective Remove `Val`'s `try_*` arithmetic methods. fixes #9571 ## Changelog Removed these methods from `bevy_ui::ui_node::Val`: - `try_add` - `try_sub` - `try_add_assign_with_size` - `try_sub_assign_with_size` - `try_add_assign` - `try_sub_assign` - `try_add_assign_with_size` - `try_sub_assign_with_size` ## Migration Guide `Val`'s `try_*` arithmetic methods have been removed. To perform arithmetic on `Val`s deconstruct them using pattern matching. |
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a2bd93aedc
|
Make GridPlacement 's fields non-zero and add accessor functions. (#9486)
# 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`. |
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90b3ac7f3a
|
Added Val::ZERO Constant (#9566)
# 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. |
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f813831409
|
fix incorrect docs for JustifyItems and JustifySelf (#9539)
# Objective Fixes incorrect docs in `bevy_ui` for `JustifyItems` and `JustifySelf`. ## Solution `JustifyItems` and `JustifySelf` target the main axis and not the cross axis. |
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546f7fc194
|
Add some missing pub in ui_node (#9529)
# 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 |
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b4bc9e4a11
|
bevy_ui: fix doc formatting for some Style fields (#9295)
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. |
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6bca129440
|
Remove out-of-date paragraph in Style::border (#9103)
# Objective - bevy now renders borders, doc is out of date ## Solution - Fix blatant lie |
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ffc572728f
|
Fix typos throughout the project (#9090)
# 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](
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9655acebb6
|
Divide by UiScale when converting UI coordinates from physical to logical (#8720)
# 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> |
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aeeb20ec4c
|
bevy_reflect: FromReflect Ergonomics Implementation (#6056)
# 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> |
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8b5bf42c28
|
UI texture atlas support (#8822)
# 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> |
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7fc6db32ce
|
Add FromReflect where Reflect is used (#8776)
# 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> |
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960e797388
|
Add UiRect::px() and UiRect::percent() utils (#8866)
# 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. |
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f7aa83a247
|
Ui Node Borders (#7795)
# 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> |
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08bf1a6c2e
|
Flatten UI Style properties that use Size + remove Size (#8548)
# 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> |
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a35ed552fa
|
Fix Node::physical_rect and add a physical_size method (#8551)
# 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. |
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85c3251c10
|
bevy_ui: Add FromReflect derives (#8495)
# 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. |
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abf12f3b3b
|
Fixed several missing links in docs. (#8117)
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> |
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09df19bcad
|
Split UI Overflow by axis (#8095)
# 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()` |
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30ac157b80
|
Register some extra types to type registry (#8430)
# 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` |
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363d0f0c7c
|
Add CSS Grid support to bevy_ui (#8026)
# 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> |
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ffc62c1a81
|
text_system split (#7779)
# 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> |
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ff9f2234f3
|
UiImage helper functions (#8199)
# 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. |
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9079f6d976
|
Fix UI node docs (#8287)
# Objective - Fix some (probably) incorrect docs. |
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2d5ef75c9f
|
Val viewport unit variants (#8137)
# 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. |
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3b51e1c8d9
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Improve the 'Val` doc comments (#8134)
# 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. |
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87dda354dd
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Remove Val::Undefined (#7485)
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f554700108
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Add methods for calculating the size and postion of UI nodes (#7930)
Co-authored-by: François <mockersf@gmail.com> |
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cfc280cbef |
Change the Node doc comments to state that it stores the size in logical pixels (#7896)
# 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. |
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76058bcf33 |
Upgrade to Taffy 0.3.3 (#7859)
# 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. |
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9153bd0e78 |
Document the border field of Style . (#7868)
# Objective Document the `border` field of `Style`. |
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f420c518c0 |
Document how padding and margin behave with percentage values (#7785)
# Objective Add a comment explaining that percentage padding is calculated based on the width of the parent node. |
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11c7e5807a |
Improve the documentation for flex-basis (#7685)
# 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. |
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5a71831b31 |
The size field of CalculatedSize should not be a Size (#7641)
# 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`. |
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16ce3859e3 |
Document how Style 's size constraints interact (#7613)
# Objective Document how `Style`'s size constraints interact. # Changelog * Added extra doc comments to `Style`'s size fields. |
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2d1dcbff7b |
Fix the AlignSelf documentation (#7577)
# 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), )); } }); } }); } ``` |
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3dd8b42f72 |
Fix various typos (#7096)
I stumbled across a typo in some docs. Fixed some more while I was in there. |
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df3673f679 |
Add const to methods and const defaults to bevy_ui (#5542)
# Objective - Fixes #5529 ## Solution - Add assosciated constants named DEFAULT to as many types as possible - Add const to as many methods in bevy_ui as possible I have not applied the same treatment to the bundles in bevy_ui as it would require going into other bevy crates to implement const defaults for structs in bevy_text or relies on UiImage which calls HandleUntyped.typed() which isn't const safe. Alternatively the defaults could relatively easily be turned into a macro to regain some of the readability and conciseness at the cost of explicitness. Such a macro that partially implements this exists as a crate here: [const-default](https://docs.rs/const-default/latest/const_default/derive.ConstDefault.html) but does not support enums. Let me know if there's anything I've missed or if I should push further into other crates. Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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2938792c7d |
Upgrade to Taffy 0.2 (#6743)
# Objective Upgrade to Taffy 0.2 ## Solution Do it ## Changelog Upgraded to Taffy 0.2, improving UI layout performance significantly and adding the flexbox `gap` property and `AlignContent::SpaceEvenly`. ## Notes `many_buttons` is 8% faster! speed improvements for more highly nested UIs will be much more dramatic. Great work, Team Taffy. |
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8545580214 |
text aspect ratio bug fix (#6825)
## Objective Bevy UI uses a `MeasureFunc` that preserves the aspect ratio of text, not just images. This means that the extent of flex-items containing text may be calculated incorrectly depending on the ratio of the text size compared to the size of its containing node. Fixes #6748 Related to #6724 with Bevy 0.9:  with this PR (accurately matching the behavior of Flexbox):  ## Solution Only perform the aspect ratio calculations if the uinode contains an image. ## Changelog * Added a field `preserve_aspect_ratio` to `CalculatedSize` * The `MeasureFunc` only preserves the aspect ratio when `preserve_aspect_ratio` is true. * `update_image_calculated_size_system` sets `preserve_aspect_ratio` to true for nodes with images. |
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5f1261110f |
Flip UI image (#6292)
# Objective Fixes #3225, Allow for flippable UI Images ## Solution Add flip_x and flip_y fields to UiImage, and swap the UV coordinates accordingly in ui_prepare_nodes. ## Changelog * Changes UiImage to a struct with texture, flip_x, and flip_y fields. * Adds flip_x and flip_y fields to ExtractedUiNode. * Changes extract_uinodes to extract the flip_x and flip_y values from UiImage. * Changes prepare_uinodes to swap the UV coordinates as required. * Changes UiImage derefs to texture field accesses. |
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7231e00507 |
Note about flex in Style docs (#6616)
# Objective - Fixes #6606 ## Solution - Deleted the note Bevy's UI being upside down since it's no longer true as of version 0.9.0 |
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4b5a33d970 |
Add z-index support with a predictable UI stack (#5877)
# Objective Add consistent UI rendering and interaction where deep nodes inside two different hierarchies will never render on top of one-another by default and offer an escape hatch (z-index) for nodes to change their depth. ## The problem with current implementation The current implementation of UI rendering is broken in that regard, mainly because [it sets the Z value of the `Transform` component based on a "global Z" space](https://github.com/bevyengine/bevy/blob/main/crates/bevy_ui/src/update.rs#L43) shared by all nodes in the UI. This doesn't account for the fact that each node's final `GlobalTransform` value will be relative to its parent. This effectively makes the depth unpredictable when two deep trees are rendered on top of one-another. At the moment, it's also up to each part of the UI code to sort all of the UI nodes. The solution that's offered here does the full sorting of UI node entities once and offers the result through a resource so that all systems can use it. ## Solution ### New ZIndex component This adds a new optional `ZIndex` enum component for nodes which offers two mechanism: - `ZIndex::Local(i32)`: Overrides the depth of the node relative to its siblings. - `ZIndex::Global(i32)`: Overrides the depth of the node relative to the UI root. This basically allows any node in the tree to "escape" the parent and be ordered relative to the entire UI. Note that in the current implementation, omitting `ZIndex` on a node has the same result as adding `ZIndex::Local(0)`. Additionally, the "global" stacking context is essentially a way to add your node to the root stacking context, so using `ZIndex::Local(n)` on a root node (one without parent) will share that space with all nodes using `Index::Global(n)`. ### New UiStack resource This adds a new `UiStack` resource which is calculated from both hierarchy and `ZIndex` during UI update and contains a vector of all node entities in the UI, ordered by depth (from farthest from camera to closest). This is exposed publicly by the bevy_ui crate with the hope that it can be used for consistent ordering and to reduce the amount of sorting that needs to be done by UI systems (i.e. instead of sorting everything by `global_transform.z` in every system, this array can be iterated over). ### New z_index example This also adds a new z_index example that showcases the new `ZIndex` component. It's also a good general demo of the new UI stack system, because making this kind of UI was very broken with the old system (e.g. nodes would render on top of each other, not respecting hierarchy or insert order at all).  --- ## Changelog - Added the `ZIndex` component to bevy_ui. - Added the `UiStack` resource to bevy_ui, and added implementation in a new `stack.rs` module. - Removed the previous Z updating system from bevy_ui, because it was replaced with the above. - Changed bevy_ui rendering to use UiStack instead of z ordering. - Changed bevy_ui focus/interaction system to use UiStack instead of z ordering. - Added a new z_index example. ## ZIndex demo Here's a demo I wrote to test these features https://user-images.githubusercontent.com/1060971/188329295-d7beebd6-9aee-43ab-821e-d437df5dbe8a.mp4 Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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9066d51420 |
Utility methods for Val (#6134)
# Objective Adds a better interface for performing mathematical operations with UI unit `Val`. Fixes #6080. ## Solution - Added `try_add` and `try_sub` methods to Val. - Removed the `Add` and `AddAssign` impls for `Val` that introduced unintuitive and bug-prone behaviour. - As a consequence of the prior, ~~changed the `Add` and `Sub` impls for the `Size` struct to take a `(Val, Val)` instead of `Vec2`~~ deleted the `Add` and `Sub` impls for the `Size` struct - Added a `From<(Val, Val)>` impl for the `Size` struct - Added `evaluate(size: f32)` method that converts from `Val::Percent` to `Val::Px`. - Added `try_add_with_size` and `try_sub_with_size` methods to `Val`, which evaluate `Val::Percent` values into `Val::Px` values before adding. --- ## Migration Guide Instead of using the + and - operators, perform calculations on `Val`s using the new `try_add` and `try_sub` methods. Multiplication and division remained unchanged. Also, when adding or subtracting from `Size`, ~~use a `Val` tuple instead of `Vec2`~~ perform the addition on `width` and `height` separately. Co-authored-by: Dawid Piotrowski <41804418+Pietrek14@users.noreply.github.com> |
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05c7babba2 |
Clarify bevy::ui::Node field and documentation (#5995)
# Objective Fixes #5820 ## Solution Change field name and documentation from `bevy::ui::Node` struct --- ## Changelog `bevy::ui::Node` `size` field has renamed to `calculated_size` ## Migration Guide All references to the old `size` name has been changed, to access `bevy::ui::Node` `size` field use `calculated_size` |
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6ce7ce208e |
Change UI coordinate system to have origin at top left corner (#6000)
# Objective Fixes #5572 ## Solution Approach is to invert the Y-axis of the UI Camera by changing the UI projection matrix to render the UI upside down. After that I'm trying to fix all issues, that pop up: - interaction expected the "old" position - images and text were displayed upside-down - baseline of text was based on the top of the glyph instead of bottom ... probably a lot more. --- Result when running examples: <details> <summary>Button example</summary> main branch:  this pr:  </details> <details> <summary>Text example</summary> m  ain branch: this pr:  </details> <details> <summary>Text debug example</summary> main branch:  this pr:  </details> <details> <summary>Transparency UI example</summary> main branch:  this pr:  </details> <details> <summary>UI example</summary> **ui example** main branch:  this pr:  </details> ## Changelog UI coordinate system and cursor position was changed from bottom left origin, y+ up to top left origin, y+ down. ## Migration Guide All flex layout should be inverted (ColumnReverse => Column, FlexStart => FlexEnd, WrapReverse => Wrap) System where dealing with cursor position should be changed to account for cursor position being based on the top left instead of bottom left |
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481eec2c92 |
Rename UiColor to BackgroundColor (#6087)
# Objective Fixes #6078. The `UiColor` component is unhelpfully named: it is unclear, ambiguous with border color and ## Solution Rename the `UiColor` component (and associated fields) to `BackgroundColor` / `background_colorl`. ## Migration Guide `UiColor` has been renamed to `BackgroundColor`. This change affects `NodeBundle`, `ButtonBundle` and `ImageBundle`. In addition, the corresponding field on `ExtractedUiNode` has been renamed to `background_color` for consistency. |
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8b7b44d839 |
Move sprite::Rect into bevy_math (#5686)
# Objective Promote the `Rect` utility of `sprite::Rect`, which defines a rectangle by its minimum and maximum corners, to the `bevy_math` crate to make it available as a general math type to all crates without the need to depend on the `bevy_sprite` crate. Fixes #5575 ## Solution Move `sprite::Rect` into `bevy_math` and fix all uses. Implement `Reflect` for `Rect` directly into the `bevy_reflect` crate by having `bevy_reflect` depend on `bevy_math`. This looks like a new dependency, but the `bevy_reflect` was "cheating" for other math types by directly depending on `glam` to reflect other math types, thereby giving the illusion that there was no dependency on `bevy_math`. In practice conceptually Bevy's math types are reflected into the `bevy_reflect` crate to avoid a dependency of that crate to a "lower level" utility crate like `bevy_math` (which in turn would make `bevy_reflect` be a dependency of most other crates, and increase the risk of circular dependencies). So this change simply formalizes that dependency in `Cargo.toml`. The `Rect` struct is also augmented in this change with a collection of utility methods to improve its usability. A few uses cases are updated to use those new methods, resulting is more clear and concise syntax. --- ## Changelog ### Changed - Moved the `sprite::Rect` type into `bevy_math`. ### Added - Added several utility methods to the `math::Rect` type. ## Migration Guide The `bevy::sprite::Rect` type moved to the math utility crate as `bevy::math::Rect`. You should change your imports from `use bevy::sprite::Rect` to `use bevy::math::Rect`. |
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675607a7e6 |
Add AUTO and UNDEFINED const constructors for Size (#5761)
# Objective Very small convenience constructors added to `Size`. Does not change current examples too much but I'm working on a rather complex UI use-case where this cuts down on some extra typing :) |
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bd008589f3 |
bevy_reflect: Update enum derives (#5473)
> In draft until #4761 is merged. See the relevant commits [here](
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bf085ee1d2 |
Remove Size and UiRect generics (#5404)
# Objective - Migrate changes from #3503. ## Solution - Change `Size<T>` and `UiRect<T>` to `Size` and `UiRect` using `Val`. - Implement `Sub`, `SubAssign`, `Mul`, `MulAssign`, `Div` and `DivAssign` for `Val`. - Update tests for `Size`. --- ## Changelog ### Changed - The generic `T` of `Size` and `UiRect` got removed and instead they both now always use `Val`. ## Migration Guide - The generic `T` of `Size` and `UiRect` got removed and instead they both now always use `Val`. If you used a `Size<f32>` consider replacing it with a `Vec2` which is way more powerful. Co-authored-by: KDecay <KDecayMusic@protonmail.com> |
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cfee0e882e |
Fix various typos (#5417)
## Objective - Fix some typos ## Solution - Fix em. - My favorite was `maxizimed` |
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01f5f8cbe3 |
Disable UI node Interaction when ComputedVisibility is false (#5361)
# Objective UI nodes can be hidden by setting their `Visibility` property. Since #5310 was merged, this is now ergonomic to use, as visibility is now inherited. However, UI nodes still receive (and store) interactions when hidden, resulting in surprising hidden state (and an inability to otherwise disable UI nodes. ## Solution Fixes #5360. I've updated the `ui_focus_system` to accomplish this in a minimally intrusive way, and updated the docs to match. **NOTE:** I have not added automated tests to verify this behavior, as we do not currently have a good testing paradigm for `bevy_ui`. I'm not thrilled with that by any means, but I'm not sure fixing it is within scope. ## Paths not taken ### Separate `Disabled` component This is a much larger and more controversial change, and not well-scoped to UI. Furthermore, it is extremely rare that you want hidden UI elements to function: the most common cases are for things like changing tabs, collapsing elements or so on. Splitting this behavior would be more complex, and substantially violate user expectations. ### A separate limbo world Mentioned in the linked issue. Super cool, but all of the problems of the `Disabled` component solution with a whole new RFC-worth of complexity. ### Using change detection to reduce the amount of redundant work Adds a lot of complexity for questionable performance gains. Likely involves a complete refactor of the entire system. We simply don't have the tests or benchmarks here to justify this. ## Changelog - UI nodes are now always in an `Interaction::None` state while they are hidden (via the `ComputedVisibility` component). |
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49ff42cc69 |
fix new clippy lints (#5160)
# Objective - Nightly clippy lints should be fixed before they get stable and break CI ## Solution - fix new clippy lints - ignore `significant_drop_in_scrutinee` since it isn't relevant in our loop https://github.com/rust-lang/rust-clippy/issues/8987 ```rust for line in io::stdin().lines() { ... } ``` Co-authored-by: Jakob Hellermann <hellermann@sipgate.de> |
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5e1756954f |
Derive default for enums where possible (#5158)
# Objective Fixes #5153 ## Solution Search for all enums and manually check if they have default impls that can use this new derive. By my reckoning: | enum | num | |-|-| | total | 159 | | has default impl | 29 | | default is unit variant | 23 | |
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f000c2b951 |
Clippy improvements (#4665)
# Objective Follow up to my previous MR #3718 to add new clippy warnings to bevy: - [x] [~~option_if_let_else~~](https://rust-lang.github.io/rust-clippy/master/#option_if_let_else) (reverted) - [x] [redundant_else](https://rust-lang.github.io/rust-clippy/master/#redundant_else) - [x] [match_same_arms](https://rust-lang.github.io/rust-clippy/master/#match_same_arms) - [x] [semicolon_if_nothing_returned](https://rust-lang.github.io/rust-clippy/master/#semicolon_if_nothing_returned) - [x] [explicit_iter_loop](https://rust-lang.github.io/rust-clippy/master/#explicit_iter_loop) - [x] [map_flatten](https://rust-lang.github.io/rust-clippy/master/#map_flatten) There is one commit per clippy warning, and the matching flags are added to the CI execution. To test the CI execution you may run `cargo run -p ci -- clippy` at the root. I choose the add the flags in the `ci` tool crate to avoid having them in every `lib.rs` but I guess it could become an issue with suprise warnings coming up after a commit/push Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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1bbd5c25c0 |
Enforce type safe usage of Handle::get (#4794)
# Objective - Sometimes, people might load an asset as one type, then use it with an `Asset`s for a different type. - See e.g. #4784. - This is especially likely with the Gltf types, since users may not have a clear conceptual model of what types the assets will be. - We had an instance of this ourselves, in the `scene_viewer` example ## Solution - Make `Assets::get` require a type safe handle. --- ## Changelog ### Changed - `Assets::<T>::get` and `Assets::<T>::get_mut` now require that the passed handles are `Handle<T>`, improving the type safety of handles. ### Added - `HandleUntyped::typed_weak`, a helper function for creating a weak typed version of an exisitng `HandleUntyped`. ## Migration Guide `Assets::<T>::get` and `Assets::<T>::get_mut` now require that the passed handles are `Handle<T>`, improving the type safety of handles. If you were previously passing in: - a `HandleId`, use `&Handle::weak(id)` instead, to create a weak handle. You may have been able to store a type safe `Handle` instead. - a `HandleUntyped`, use `&handle_untyped.typed_weak()` to create a weak handle of the specified type. This is most likely to be the useful when using [load_folder](https://docs.rs/bevy_asset/latest/bevy_asset/struct.AssetServer.html#method.load_folder) - a `Handle<U>` of of a different type, consider whether this is the correct handle type to store. If it is (i.e. the same handle id is used for multiple different Asset types) use `Handle::weak(handle.id)` to cast to a different type. |
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2b6e67f4cb |
add #[reflect(Default)] to create default value for reflected types (#3733)
### Problem It currently isn't possible to construct the default value of a reflected type. Because of that, it isn't possible to use `add_component` of `ReflectComponent` to add a new component to an entity because you can't know what the initial value should be. ### Solution 1. add `ReflectDefault` type ```rust #[derive(Clone)] pub struct ReflectDefault { default: fn() -> Box<dyn Reflect>, } impl ReflectDefault { pub fn default(&self) -> Box<dyn Reflect> { (self.default)() } } impl<T: Reflect + Default> FromType<T> for ReflectDefault { fn from_type() -> Self { ReflectDefault { default: || Box::new(T::default()), } } } ``` 2. add `#[reflect(Default)]` to all component types that implement `Default` and are user facing (so not `ComputedSize`, `CubemapVisibleEntities` etc.) This makes it possible to add the default value of a component to an entity without any compile-time information: ```rust fn main() { let mut app = App::new(); app.register_type::<Camera>(); let type_registry = app.world.get_resource::<TypeRegistry>().unwrap(); let type_registry = type_registry.read(); let camera_registration = type_registry.get(std::any::TypeId::of::<Camera>()).unwrap(); let reflect_default = camera_registration.data::<ReflectDefault>().unwrap(); let reflect_component = camera_registration .data::<ReflectComponent>() .unwrap() .clone(); let default = reflect_default.default(); drop(type_registry); let entity = app.world.spawn().id(); reflect_component.add_component(&mut app.world, entity, &*default); let camera = app.world.entity(entity).get::<Camera>().unwrap(); dbg!(&camera); } ``` ### Open questions - should we have `ReflectDefault` or `ReflectFromWorld` or both? |
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989fb8a78d |
Move Rect to bevy_ui and rename it to UiRect (#4276)
# Objective - Closes #335. - Related #4285. - Part of the splitting process of #3503. ## Solution - Move `Rect` to `bevy_ui` and rename it to `UiRect`. ## Reasons - `Rect` is only used in `bevy_ui` and therefore calling it `UiRect` makes the intent clearer. - We have two types that are called `Rect` currently and it's missleading (see `bevy_sprite::Rect` and #335). - Discussion in #3503. ## Changelog ### Changed - The `Rect` type got moved from `bevy_math` to `bevy_ui` and renamed to `UiRect`. ## Migration Guide - The `Rect` type got renamed to `UiRect`. To migrate you just have to change every occurrence of `Rect` to `UiRect`. Co-authored-by: KDecay <KDecayMusic@protonmail.com> |
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7a7f097485 |
Move Size to bevy_ui (#4285)
# Objective - Related #4276. - Part of the splitting process of #3503. ## Solution - Move `Size` to `bevy_ui`. ## Reasons - `Size` is only needed in `bevy_ui` (because it needs to use `Val` instead of `f32`), but it's also used as a worse `Vec2` replacement in other areas. - `Vec2` is more powerful than `Size` so it should be used whenever possible. - Discussion in #3503. ## Changelog ### Changed - The `Size` type got moved from `bevy_math` to `bevy_ui`. ## Migration Guide - The `Size` type got moved from `bevy::math` to `bevy::ui`. To migrate you just have to import `bevy::ui::Size` instead of `bevy::math::Math` or use the `bevy::prelude` instead. Co-authored-by: KDecay <KDecayMusic@protonmail.com> |
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32f7997c56 |
Partially document bevy_ui (#3526)
# Objective Updated the docs for bevy_ui as requested by #3492 ## Solution I have documented the parts I understand. anchors.rs is not in use and should be removed, thus I haven't documented that, and some of the more renderer-heavy code is beyond me and needs input from either cart or someone familiar with bevy rendering Co-authored-by: Troels Jessen <kairyuka@gmail.com> |
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340957994d |
Implement the Overflow::Hidden style property for UI (#3296)
# Objective This PR implements the `overflow` style property in `bevy_ui`. When set to `Overflow::Hidden`, the children of that node are clipped so that overflowing parts are not rendered. This is an important building block for UI widgets. ## Solution Clipping is done on the CPU so that it does not break batching. The clip regions update was implemented as a separate system for clarity, but it could be merged with the other UI systems to avoid doing an additional tree traversal. (I don't think it's important until we fix the layout performance issues though). A scrolling list was added to the `ui_pipelined` example to showcase `Overflow::Hidden`. For the sake of simplicity, it can only be scrolled with a mouse. |
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ffecb05a0a |
Replace old renderer with new renderer (#3312)
This makes the [New Bevy Renderer](#2535) the default (and only) renderer. The new renderer isn't _quite_ ready for the final release yet, but I want as many people as possible to start testing it so we can identify bugs and address feedback prior to release. The examples are all ported over and operational with a few exceptions: * I removed a good portion of the examples in the `shader` folder. We still have some work to do in order to make these examples possible / ergonomic / worthwhile: #3120 and "high level shader material plugins" are the big ones. This is a temporary measure. * Temporarily removed the multiple_windows example: doing this properly in the new renderer will require the upcoming "render targets" changes. Same goes for the render_to_texture example. * Removed z_sort_debug: entity visibility sort info is no longer available in app logic. we could do this on the "render app" side, but i dont consider it a priority. |
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a5c675f336 |
Add docstring comment to Style to reference CSS (#2936)
Mention the fact that the UI layout system is based on the CSS layout model through a docstring comment on the `Style` type. # Objective Explain to new users that the Bevy UI uses the CSS layout model, to lower the barrier to entry given the fact documentation (book and code) is fairly limited on the topic. ## Solution Fix as discussed with @alice-i-cecile on #2918. |
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2974293682 |
Add ControlNode for UI (#2908)
This PR adds a ControlNode which marks an entity as "transparent" to the UI layout system, meaning the children of this entity will be treated as the children of this entity s parent by the layout system(s). |
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07ed1d053e |
Implement and require #[derive(Component)] on all component structs (#2254)
This implements the most minimal variant of #1843 - a derive for marker trait. This is a prerequisite to more complicated features like statically defined storage type or opt-out component reflection. In order to make component struct's purpose explicit and avoid misuse, it must be annotated with `#[derive(Component)]` (manual impl is discouraged for compatibility). Right now this is just a marker trait, but in the future it might be expanded. Making this change early allows us to make further changes later without breaking backward compatibility for derive macro users. This already prevents a lot of issues, like using bundles in `insert` calls. Primitive types are no longer valid components as well. This can be easily worked around by adding newtype wrappers and deriving `Component` for them. One funny example of prevented bad code (from our own tests) is when an newtype struct or enum variant is used. Previously, it was possible to write `insert(Newtype)` instead of `insert(Newtype(value))`. That code compiled, because function pointers (in this case newtype struct constructor) implement `Send + Sync + 'static`, so we allowed them to be used as components. This is no longer the case and such invalid code will trigger a compile error. Co-authored-by: = <=> Co-authored-by: TheRawMeatball <therawmeatball@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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958f8b124a |
Use Explicit Names for Flex Direction (#2672)
# Objective - Clarify vague meaning of "Ltr" and "Rtl". For someone familiar with Flex Box, this is easy to understand, but being more explicit will help beginners or those unfamiliar, without the need to do research. ## Solution - Change three letter abbreviation to fully descriptive name. |
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be1c317d4e |
Resolve (most) internal system ambiguities (#1606)
* Adds labels and orderings to systems that need them (uses the new many-to-many labels for InputSystem) * Removes the Event, PreEvent, Scene, and Ui stages in favor of First, PreUpdate, and PostUpdate (there is more collapsing potential, such as the Asset stages and _maybe_ removing First, but those have more nuance so they should be handled separately) * Ambiguity detection now prints component conflicts * Removed broken change filters from flex calculation (which implicitly relied on the z-update system always modifying translation.z). This will require more work to make it behave as expected so i just removed it (and it was already doing this work every frame). |
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faeccd7a09 |
Reflection cleanup (#1536)
This is an effort to provide the correct `#[reflect_value(...)]` attributes where they are needed. Supersedes #1533 and resolves #1528. --- I am working under the following assumptions (thanks to @bjorn3 and @Davier for advice here): - Any `enum` that derives `Reflect` and one or more of { `Serialize`, `Deserialize`, `PartialEq`, `Hash` } needs a `#[reflect_value(...)]` attribute containing the same subset of { `Serialize`, `Deserialize`, `PartialEq`, `Hash` } that is present on the derive. - Same as above for `struct` and `#[reflect(...)]`, respectively. - If a `struct` is used as a component, it should also have `#[reflect(Component)]` - All reflected types should be registered in their plugins I treated the following as components (added `#[reflect(Component)]` if necessary): - `bevy_render` - `struct RenderLayers` - `bevy_transform` - `struct GlobalTransform` - `struct Parent` - `struct Transform` - `bevy_ui` - `struct Style` Not treated as components: - `bevy_math` - `struct Size<T>` - `struct Rect<T>` - Note: The updates for `Size<T>` and `Rect<T>` in `bevy::math::geometry` required using @Davier's suggestion to add `+ PartialEq` to the trait bound. I then registered the specific types used over in `bevy_ui` such as `Size<Val>`, etc. in `bevy_ui`'s plugin, since `bevy::math` does not contain a plugin. - `bevy_render` - `struct Color` - `struct PipelineSpecialization` - `struct ShaderSpecialization` - `enum PrimitiveTopology` - `enum IndexFormat` Not Addressed: - I am not searching for components in Bevy that are _not_ reflected. So if there are components that are not reflected that should be reflected, that will need to be figured out in another PR. - I only added `#[reflect(...)]` or `#[reflect_value(...)]` entries for the set of four traits { `Serialize`, `Deserialize`, `PartialEq`, `Hash` } _if they were derived via `#[derive(...)]`_. I did not look for manual trait implementations of the same set of four, nor did I consider any traits outside the four. Are those other possibilities something that needs to be looked into? |
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3a2a68852c |
Bevy ECS V2 (#1525)
# Bevy ECS V2 This is a rewrite of Bevy ECS (basically everything but the new executor/schedule, which are already awesome). The overall goal was to improve the performance and versatility of Bevy ECS. Here is a quick bulleted list of changes before we dive into the details: * Complete World rewrite * Multiple component storage types: * Tables: fast cache friendly iteration, slower add/removes (previously called Archetypes) * Sparse Sets: fast add/remove, slower iteration * Stateful Queries (caches query results for faster iteration. fragmented iteration is _fast_ now) * Stateful System Params (caches expensive operations. inspired by @DJMcNab's work in #1364) * Configurable System Params (users can set configuration when they construct their systems. once again inspired by @DJMcNab's work) * Archetypes are now "just metadata", component storage is separate * Archetype Graph (for faster archetype changes) * Component Metadata * Configure component storage type * Retrieve information about component size/type/name/layout/send-ness/etc * Components are uniquely identified by a densely packed ComponentId * TypeIds are now totally optional (which should make implementing scripting easier) * Super fast "for_each" query iterators * Merged Resources into World. Resources are now just a special type of component * EntityRef/EntityMut builder apis (more efficient and more ergonomic) * Fast bitset-backed `Access<T>` replaces old hashmap-based approach everywhere * Query conflicts are determined by component access instead of archetype component access (to avoid random failures at runtime) * With/Without are still taken into account for conflicts, so this should still be comfy to use * Much simpler `IntoSystem` impl * Significantly reduced the amount of hashing throughout the ecs in favor of Sparse Sets (indexed by densely packed ArchetypeId, ComponentId, BundleId, and TableId) * Safety Improvements * Entity reservation uses a normal world reference instead of unsafe transmute * QuerySets no longer transmute lifetimes * Made traits "unsafe" where relevant * More thorough safety docs * WorldCell * Exposes safe mutable access to multiple resources at a time in a World * Replaced "catch all" `System::update_archetypes(world: &World)` with `System::new_archetype(archetype: &Archetype)` * Simpler Bundle implementation * Replaced slow "remove_bundle_one_by_one" used as fallback for Commands::remove_bundle with fast "remove_bundle_intersection" * Removed `Mut<T>` query impl. it is better to only support one way: `&mut T` * Removed with() from `Flags<T>` in favor of `Option<Flags<T>>`, which allows querying for flags to be "filtered" by default * Components now have is_send property (currently only resources support non-send) * More granular module organization * New `RemovedComponents<T>` SystemParam that replaces `query.removed::<T>()` * `world.resource_scope()` for mutable access to resources and world at the same time * WorldQuery and QueryFilter traits unified. FilterFetch trait added to enable "short circuit" filtering. Auto impled for cases that don't need it * Significantly slimmed down SystemState in favor of individual SystemParam state * System Commands changed from `commands: &mut Commands` back to `mut commands: Commands` (to allow Commands to have a World reference) Fixes #1320 ## `World` Rewrite This is a from-scratch rewrite of `World` that fills the niche that `hecs` used to. Yes, this means Bevy ECS is no longer a "fork" of hecs. We're going out our own! (the only shared code between the projects is the entity id allocator, which is already basically ideal) A huge shout out to @SanderMertens (author of [flecs](https://github.com/SanderMertens/flecs)) for sharing some great ideas with me (specifically hybrid ecs storage and archetype graphs). He also helped advise on a number of implementation details. ## Component Storage (The Problem) Two ECS storage paradigms have gained a lot of traction over the years: * **Archetypal ECS**: * Stores components in "tables" with static schemas. Each "column" stores components of a given type. Each "row" is an entity. * Each "archetype" has its own table. Adding/removing an entity's component changes the archetype. * Enables super-fast Query iteration due to its cache-friendly data layout * Comes at the cost of more expensive add/remove operations for an Entity's components, because all components need to be copied to the new archetype's "table" * **Sparse Set ECS**: * Stores components of the same type in densely packed arrays, which are sparsely indexed by densely packed unsigned integers (Entity ids) * Query iteration is slower than Archetypal ECS because each entity's component could be at any position in the sparse set. This "random access" pattern isn't cache friendly. Additionally, there is an extra layer of indirection because you must first map the entity id to an index in the component array. * Adding/removing components is a cheap, constant time operation Bevy ECS V1, hecs, legion, flec, and Unity DOTS are all "archetypal ecs-es". I personally think "archetypal" storage is a good default for game engines. An entity's archetype doesn't need to change frequently in general, and it creates "fast by default" query iteration (which is a much more common operation). It is also "self optimizing". Users don't need to think about optimizing component layouts for iteration performance. It "just works" without any extra boilerplate. Shipyard and EnTT are "sparse set ecs-es". They employ "packing" as a way to work around the "suboptimal by default" iteration performance for specific sets of components. This helps, but I didn't think this was a good choice for a general purpose engine like Bevy because: 1. "packs" conflict with each other. If bevy decides to internally pack the Transform and GlobalTransform components, users are then blocked if they want to pack some custom component with Transform. 2. users need to take manual action to optimize Developers selecting an ECS framework are stuck with a hard choice. Select an "archetypal" framework with "fast iteration everywhere" but without the ability to cheaply add/remove components, or select a "sparse set" framework to cheaply add/remove components but with slower iteration performance. ## Hybrid Component Storage (The Solution) In Bevy ECS V2, we get to have our cake and eat it too. It now has _both_ of the component storage types above (and more can be added later if needed): * **Tables** (aka "archetypal" storage) * The default storage. If you don't configure anything, this is what you get * Fast iteration by default * Slower add/remove operations * **Sparse Sets** * Opt-in * Slower iteration * Faster add/remove operations These storage types complement each other perfectly. By default Query iteration is fast. If developers know that they want to add/remove a component at high frequencies, they can set the storage to "sparse set": ```rust world.register_component( ComponentDescriptor:🆕:<MyComponent>(StorageType::SparseSet) ).unwrap(); ``` ## Archetypes Archetypes are now "just metadata" ... they no longer store components directly. They do store: * The `ComponentId`s of each of the Archetype's components (and that component's storage type) * Archetypes are uniquely defined by their component layouts * For example: entities with "table" components `[A, B, C]` _and_ "sparse set" components `[D, E]` will always be in the same archetype. * The `TableId` associated with the archetype * For now each archetype has exactly one table (which can have no components), * There is a 1->Many relationship from Tables->Archetypes. A given table could have any number of archetype components stored in it: * Ex: an entity with "table storage" components `[A, B, C]` and "sparse set" components `[D, E]` will share the same `[A, B, C]` table as an entity with `[A, B, C]` table component and `[F]` sparse set components. * This 1->Many relationship is how we preserve fast "cache friendly" iteration performance when possible (more on this later) * A list of entities that are in the archetype and the row id of the table they are in * ArchetypeComponentIds * unique densely packed identifiers for (ArchetypeId, ComponentId) pairs * used by the schedule executor for cheap system access control * "Archetype Graph Edges" (see the next section) ## The "Archetype Graph" Archetype changes in Bevy (and a number of other archetypal ecs-es) have historically been expensive to compute. First, you need to allocate a new vector of the entity's current component ids, add or remove components based on the operation performed, sort it (to ensure it is order-independent), then hash it to find the archetype (if it exists). And thats all before we get to the _already_ expensive full copy of all components to the new table storage. The solution is to build a "graph" of archetypes to cache these results. @SanderMertens first exposed me to the idea (and he got it from @gjroelofs, who came up with it). They propose adding directed edges between archetypes for add/remove component operations. If `ComponentId`s are densely packed, you can use sparse sets to cheaply jump between archetypes. Bevy takes this one step further by using add/remove `Bundle` edges instead of `Component` edges. Bevy encourages the use of `Bundles` to group add/remove operations. This is largely for "clearer game logic" reasons, but it also helps cut down on the number of archetype changes required. `Bundles` now also have densely-packed `BundleId`s. This allows us to use a _single_ edge for each bundle operation (rather than needing to traverse N edges ... one for each component). Single component operations are also bundles, so this is strictly an improvement over a "component only" graph. As a result, an operation that used to be _heavy_ (both for allocations and compute) is now two dirt-cheap array lookups and zero allocations. ## Stateful Queries World queries are now stateful. This allows us to: 1. Cache archetype (and table) matches * This resolves another issue with (naive) archetypal ECS: query performance getting worse as the number of archetypes goes up (and fragmentation occurs). 2. Cache Fetch and Filter state * The expensive parts of fetch/filter operations (such as hashing the TypeId to find the ComponentId) now only happen once when the Query is first constructed 3. Incrementally build up state * When new archetypes are added, we only process the new archetypes (no need to rebuild state for old archetypes) As a result, the direct `World` query api now looks like this: ```rust let mut query = world.query::<(&A, &mut B)>(); for (a, mut b) in query.iter_mut(&mut world) { } ``` Requiring `World` to generate stateful queries (rather than letting the `QueryState` type be constructed separately) allows us to ensure that _all_ queries are properly initialized (and the relevant world state, such as ComponentIds). This enables QueryState to remove branches from its operations that check for initialization status (and also enables query.iter() to take an immutable world reference because it doesn't need to initialize anything in world). However in systems, this is a non-breaking change. State management is done internally by the relevant SystemParam. ## Stateful SystemParams Like Queries, `SystemParams` now also cache state. For example, `Query` system params store the "stateful query" state mentioned above. Commands store their internal `CommandQueue`. This means you can now safely use as many separate `Commands` parameters in your system as you want. `Local<T>` system params store their `T` value in their state (instead of in Resources). SystemParam state also enabled a significant slim-down of SystemState. It is much nicer to look at now. Per-SystemParam state naturally insulates us from an "aliased mut" class of errors we have hit in the past (ex: using multiple `Commands` system params). (credit goes to @DJMcNab for the initial idea and draft pr here #1364) ## Configurable SystemParams @DJMcNab also had the great idea to make SystemParams configurable. This allows users to provide some initial configuration / values for system parameters (when possible). Most SystemParams have no config (the config type is `()`), but the `Local<T>` param now supports user-provided parameters: ```rust fn foo(value: Local<usize>) { } app.add_system(foo.system().config(|c| c.0 = Some(10))); ``` ## Uber Fast "for_each" Query Iterators Developers now have the choice to use a fast "for_each" iterator, which yields ~1.5-3x iteration speed improvements for "fragmented iteration", and minor ~1.2x iteration speed improvements for unfragmented iteration. ```rust fn system(query: Query<(&A, &mut B)>) { // you now have the option to do this for a speed boost query.for_each_mut(|(a, mut b)| { }); // however normal iterators are still available for (a, mut b) in query.iter_mut() { } } ``` I think in most cases we should continue to encourage "normal" iterators as they are more flexible and more "rust idiomatic". But when that extra "oomf" is needed, it makes sense to use `for_each`. We should also consider using `for_each` for internal bevy systems to give our users a nice speed boost (but that should be a separate pr). ## Component Metadata `World` now has a `Components` collection, which is accessible via `world.components()`. This stores mappings from `ComponentId` to `ComponentInfo`, as well as `TypeId` to `ComponentId` mappings (where relevant). `ComponentInfo` stores information about the component, such as ComponentId, TypeId, memory layout, send-ness (currently limited to resources), and storage type. ## Significantly Cheaper `Access<T>` We used to use `TypeAccess<TypeId>` to manage read/write component/archetype-component access. This was expensive because TypeIds must be hashed and compared individually. The parallel executor got around this by "condensing" type ids into bitset-backed access types. This worked, but it had to be re-generated from the `TypeAccess<TypeId>`sources every time archetypes changed. This pr removes TypeAccess in favor of faster bitset access everywhere. We can do this thanks to the move to densely packed `ComponentId`s and `ArchetypeComponentId`s. ## Merged Resources into World Resources had a lot of redundant functionality with Components. They stored typed data, they had access control, they had unique ids, they were queryable via SystemParams, etc. In fact the _only_ major difference between them was that they were unique (and didn't correlate to an entity). Separate resources also had the downside of requiring a separate set of access controls, which meant the parallel executor needed to compare more bitsets per system and manage more state. I initially got the "separate resources" idea from `legion`. I think that design was motivated by the fact that it made the direct world query/resource lifetime interactions more manageable. It certainly made our lives easier when using Resources alongside hecs/bevy_ecs. However we already have a construct for safely and ergonomically managing in-world lifetimes: systems (which use `Access<T>` internally). This pr merges Resources into World: ```rust world.insert_resource(1); world.insert_resource(2.0); let a = world.get_resource::<i32>().unwrap(); let mut b = world.get_resource_mut::<f64>().unwrap(); *b = 3.0; ``` Resources are now just a special kind of component. They have their own ComponentIds (and their own resource TypeId->ComponentId scope, so they don't conflict wit components of the same type). They are stored in a special "resource archetype", which stores components inside the archetype using a new `unique_components` sparse set (note that this sparse set could later be used to implement Tags). This allows us to keep the code size small by reusing existing datastructures (namely Column, Archetype, ComponentFlags, and ComponentInfo). This allows us the executor to use a single `Access<ArchetypeComponentId>` per system. It should also make scripting language integration easier. _But_ this merge did create problems for people directly interacting with `World`. What if you need mutable access to multiple resources at the same time? `world.get_resource_mut()` borrows World mutably! ## WorldCell WorldCell applies the `Access<ArchetypeComponentId>` concept to direct world access: ```rust let world_cell = world.cell(); let a = world_cell.get_resource_mut::<i32>().unwrap(); let b = world_cell.get_resource_mut::<f64>().unwrap(); ``` This adds cheap runtime checks (a sparse set lookup of `ArchetypeComponentId` and a counter) to ensure that world accesses do not conflict with each other. Each operation returns a `WorldBorrow<'w, T>` or `WorldBorrowMut<'w, T>` wrapper type, which will release the relevant ArchetypeComponentId resources when dropped. World caches the access sparse set (and only one cell can exist at a time), so `world.cell()` is a cheap operation. WorldCell does _not_ use atomic operations. It is non-send, does a mutable borrow of world to prevent other accesses, and uses a simple `Rc<RefCell<ArchetypeComponentAccess>>` wrapper in each WorldBorrow pointer. The api is currently limited to resource access, but it can and should be extended to queries / entity component access. ## Resource Scopes WorldCell does not yet support component queries, and even when it does there are sometimes legitimate reasons to want a mutable world ref _and_ a mutable resource ref (ex: bevy_render and bevy_scene both need this). In these cases we could always drop down to the unsafe `world.get_resource_unchecked_mut()`, but that is not ideal! Instead developers can use a "resource scope" ```rust world.resource_scope(|world: &mut World, a: &mut A| { }) ``` This temporarily removes the `A` resource from `World`, provides mutable pointers to both, and re-adds A to World when finished. Thanks to the move to ComponentIds/sparse sets, this is a cheap operation. If multiple resources are required, scopes can be nested. We could also consider adding a "resource tuple" to the api if this pattern becomes common and the boilerplate gets nasty. ## Query Conflicts Use ComponentId Instead of ArchetypeComponentId For safety reasons, systems cannot contain queries that conflict with each other without wrapping them in a QuerySet. On bevy `main`, we use ArchetypeComponentIds to determine conflicts. This is nice because it can take into account filters: ```rust // these queries will never conflict due to their filters fn filter_system(a: Query<&mut A, With<B>>, b: Query<&mut B, Without<B>>) { } ``` But it also has a significant downside: ```rust // these queries will not conflict _until_ an entity with A, B, and C is spawned fn maybe_conflicts_system(a: Query<(&mut A, &C)>, b: Query<(&mut A, &B)>) { } ``` The system above will panic at runtime if an entity with A, B, and C is spawned. This makes it hard to trust that your game logic will run without crashing. In this pr, I switched to using `ComponentId` instead. This _is_ more constraining. `maybe_conflicts_system` will now always fail, but it will do it consistently at startup. Naively, it would also _disallow_ `filter_system`, which would be a significant downgrade in usability. Bevy has a number of internal systems that rely on disjoint queries and I expect it to be a common pattern in userspace. To resolve this, I added a new `FilteredAccess<T>` type, which wraps `Access<T>` and adds with/without filters. If two `FilteredAccess` have with/without values that prove they are disjoint, they will no longer conflict. ## EntityRef / EntityMut World entity operations on `main` require that the user passes in an `entity` id to each operation: ```rust let entity = world.spawn((A, )); // create a new entity with A world.get::<A>(entity); world.insert(entity, (B, C)); world.insert_one(entity, D); ``` This means that each operation needs to look up the entity location / verify its validity. The initial spawn operation also requires a Bundle as input. This can be awkward when no components are required (or one component is required). These operations have been replaced by `EntityRef` and `EntityMut`, which are "builder-style" wrappers around world that provide read and read/write operations on a single, pre-validated entity: ```rust // spawn now takes no inputs and returns an EntityMut let entity = world.spawn() .insert(A) // insert a single component into the entity .insert_bundle((B, C)) // insert a bundle of components into the entity .id() // id returns the Entity id // Returns EntityMut (or panics if the entity does not exist) world.entity_mut(entity) .insert(D) .insert_bundle(SomeBundle::default()); { // returns EntityRef (or panics if the entity does not exist) let d = world.entity(entity) .get::<D>() // gets the D component .unwrap(); // world.get still exists for ergonomics let d = world.get::<D>(entity).unwrap(); } // These variants return Options if you want to check existence instead of panicing world.get_entity_mut(entity) .unwrap() .insert(E); if let Some(entity_ref) = world.get_entity(entity) { let d = entity_ref.get::<D>().unwrap(); } ``` This _does not_ affect the current Commands api or terminology. I think that should be a separate conversation as that is a much larger breaking change. ## Safety Improvements * Entity reservation in Commands uses a normal world borrow instead of an unsafe transmute * QuerySets no longer transmutes lifetimes * Made traits "unsafe" when implementing a trait incorrectly could cause unsafety * More thorough safety docs ## RemovedComponents SystemParam The old approach to querying removed components: `query.removed:<T>()` was confusing because it had no connection to the query itself. I replaced it with the following, which is both clearer and allows us to cache the ComponentId mapping in the SystemParamState: ```rust fn system(removed: RemovedComponents<T>) { for entity in removed.iter() { } } ``` ## Simpler Bundle implementation Bundles are no longer responsible for sorting (or deduping) TypeInfo. They are just a simple ordered list of component types / data. This makes the implementation smaller and opens the door to an easy "nested bundle" implementation in the future (which i might even add in this pr). Duplicate detection is now done once per bundle type by World the first time a bundle is used. ## Unified WorldQuery and QueryFilter types (don't worry they are still separate type _parameters_ in Queries .. this is a non-breaking change) WorldQuery and QueryFilter were already basically identical apis. With the addition of `FetchState` and more storage-specific fetch methods, the overlap was even clearer (and the redundancy more painful). QueryFilters are now just `F: WorldQuery where F::Fetch: FilterFetch`. FilterFetch requires `Fetch<Item = bool>` and adds new "short circuit" variants of fetch methods. This enables a filter tuple like `(With<A>, Without<B>, Changed<C>)` to stop evaluating the filter after the first mismatch is encountered. FilterFetch is automatically implemented for `Fetch` implementations that return bool. This forces fetch implementations that return things like `(bool, bool, bool)` (such as the filter above) to manually implement FilterFetch and decide whether or not to short-circuit. ## More Granular Modules World no longer globs all of the internal modules together. It now exports `core`, `system`, and `schedule` separately. I'm also considering exporting `core` submodules directly as that is still pretty "glob-ey" and unorganized (feedback welcome here). ## Remaining Draft Work (to be done in this pr) * ~~panic on conflicting WorldQuery fetches (&A, &mut A)~~ * ~~bevy `main` and hecs both currently allow this, but we should protect against it if possible~~ * ~~batch_iter / par_iter (currently stubbed out)~~ * ~~ChangedRes~~ * ~~I skipped this while we sort out #1313. This pr should be adapted to account for whatever we land on there~~. * ~~The `Archetypes` and `Tables` collections use hashes of sorted lists of component ids to uniquely identify each archetype/table. This hash is then used as the key in a HashMap to look up the relevant ArchetypeId or TableId. (which doesn't handle hash collisions properly)~~ * ~~It is currently unsafe to generate a Query from "World A", then use it on "World B" (despite the api claiming it is safe). We should probably close this gap. This could be done by adding a randomly generated WorldId to each world, then storing that id in each Query. They could then be compared to each other on each `query.do_thing(&world)` operation. This _does_ add an extra branch to each query operation, so I'm open to other suggestions if people have them.~~ * ~~Nested Bundles (if i find time)~~ ## Potential Future Work * Expand WorldCell to support queries. * Consider not allocating in the empty archetype on `world.spawn()` * ex: return something like EntityMutUninit, which turns into EntityMut after an `insert` or `insert_bundle` op * this actually regressed performance last time i tried it, but in theory it should be faster * Optimize SparseSet::insert (see `PERF` comment on insert) * Replace SparseArray `Option<T>` with T::MAX to cut down on branching * would enable cheaper get_unchecked() operations * upstream fixedbitset optimizations * fixedbitset could be allocation free for small block counts (store blocks in a SmallVec) * fixedbitset could have a const constructor * Consider implementing Tags (archetype-specific by-value data that affects archetype identity) * ex: ArchetypeA could have `[A, B, C]` table components and `[D(1)]` "tag" component. ArchetypeB could have `[A, B, C]` table components and a `[D(2)]` tag component. The archetypes are different, despite both having D tags because the value inside D is different. * this could potentially build on top of the `archetype.unique_components` added in this pr for resource storage. * Consider reverting `all_tuples` proc macro in favor of the old `macro_rules` implementation * all_tuples is more flexible and produces cleaner documentation (the macro_rules version produces weird type parameter orders due to parser constraints) * but unfortunately all_tuples also appears to make Rust Analyzer sad/slow when working inside of `bevy_ecs` (does not affect user code) * Consider "resource queries" and/or "mixed resource and entity component queries" as an alternative to WorldCell * this is basically just "systems" so maybe it's not worth it * Add more world ops * `world.clear()` * `world.reserve<T: Bundle>(count: usize)` * Try using the old archetype allocation strategy (allocate new memory on resize and copy everything over). I expect this to improve batch insertion performance at the cost of unbatched performance. But thats just a guess. I'm not an allocation perf pro :) * Adapt Commands apis for consistency with new World apis ## Benchmarks key: * `bevy_old`: bevy `main` branch * `bevy`: this branch * `_foreach`: uses an optimized for_each iterator * ` _sparse`: uses sparse set storage (if unspecified assume table storage) * `_system`: runs inside a system (if unspecified assume test happens via direct world ops) ### Simple Insert (from ecs_bench_suite)  ### Simpler Iter (from ecs_bench_suite)  ### Fragment Iter (from ecs_bench_suite)  ### Sparse Fragmented Iter Iterate a query that matches 5 entities from a single matching archetype, but there are 100 unmatching archetypes  ### Schedule (from ecs_bench_suite)  ### Add Remove Component (from ecs_bench_suite)  ### Add Remove Component Big Same as the test above, but each entity has 5 "large" matrix components and 1 "large" matrix component is added and removed  ### Get Component Looks up a single component value a large number of times  |
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e5b0c65c86 |
rename bevy_ui::node module so that bevy_ui::render::node isn't shadowed (#1464)
Previously the `mod node` shadowed the `pub use render::node`, and `CAMERA_UI`, `NODE` and `UI_PASS` constants couldn't be used. |