# Bevy Asset V2 Proposal
## Why Does Bevy Need A New Asset System?
Asset pipelines are a central part of the gamedev process. Bevy's
current asset system is missing a number of features that make it
non-viable for many classes of gamedev. After plenty of discussions and
[a long community feedback
period](https://github.com/bevyengine/bevy/discussions/3972), we've
identified a number missing features:
* **Asset Preprocessing**: it should be possible to "preprocess" /
"compile" / "crunch" assets at "development time" rather than when the
game starts up. This enables offloading expensive work from deployed
apps, faster asset loading, less runtime memory usage, etc.
* **Per-Asset Loader Settings**: Individual assets cannot define their
own loaders that override the defaults. Additionally, they cannot
provide per-asset settings to their loaders. This is a huge limitation,
as many asset types don't provide all information necessary for Bevy
_inside_ the asset. For example, a raw PNG image says nothing about how
it should be sampled (ex: linear vs nearest).
* **Asset `.meta` files**: assets should have configuration files stored
adjacent to the asset in question, which allows the user to configure
asset-type-specific settings. These settings should be accessible during
the pre-processing phase. Modifying a `.meta` file should trigger a
re-processing / re-load of the asset. It should be possible to configure
asset loaders from the meta file.
* **Processed Asset Hot Reloading**: Changes to processed assets (or
their dependencies) should result in re-processing them and re-loading
the results in live Bevy Apps.
* **Asset Dependency Tracking**: The current bevy_asset has no good way
to wait for asset dependencies to load. It punts this as an exercise for
consumers of the loader apis, which is unreasonable and error prone.
There should be easy, ergonomic ways to wait for assets to load and
block some logic on an asset's entire dependency tree loading.
* **Runtime Asset Loading**: it should be (optionally) possible to load
arbitrary assets dynamically at runtime. This necessitates being able to
deploy and run the asset server alongside Bevy Apps on _all platforms_.
For example, we should be able to invoke the shader compiler at runtime,
stream scenes from sources like the internet, etc. To keep deployed
binaries (and startup times) small, the runtime asset server
configuration should be configurable with different settings compared to
the "pre processor asset server".
* **Multiple Backends**: It should be possible to load assets from
arbitrary sources (filesystems, the internet, remote asset serves, etc).
* **Asset Packing**: It should be possible to deploy assets in
compressed "packs", which makes it easier and more efficient to
distribute assets with Bevy Apps.
* **Asset Handoff**: It should be possible to hold a "live" asset
handle, which correlates to runtime data, without actually holding the
asset in memory. Ex: it must be possible to hold a reference to a GPU
mesh generated from a "mesh asset" without keeping the mesh data in CPU
memory
* **Per-Platform Processed Assets**: Different platforms and app
distributions have different capabilities and requirements. Some
platforms need lower asset resolutions or different asset formats to
operate within the hardware constraints of the platform. It should be
possible to define per-platform asset processing profiles. And it should
be possible to deploy only the assets required for a given platform.
These features have architectural implications that are significant
enough to require a full rewrite. The current Bevy Asset implementation
got us this far, but it can take us no farther. This PR defines a brand
new asset system that implements most of these features, while laying
the foundations for the remaining features to be built.
## Bevy Asset V2
Here is a quick overview of the features introduced in this PR.
* **Asset Preprocessing**: Preprocess assets at development time into
more efficient (and configurable) representations
* **Dependency Aware**: Dependencies required to process an asset are
tracked. If an asset's processed dependency changes, it will be
reprocessed
* **Hot Reprocessing/Reloading**: detect changes to asset source files,
reprocess them if they have changed, and then hot-reload them in Bevy
Apps.
* **Only Process Changes**: Assets are only re-processed when their
source file (or meta file) has changed. This uses hashing and timestamps
to avoid processing assets that haven't changed.
* **Transactional and Reliable**: Uses write-ahead logging (a technique
commonly used by databases) to recover from crashes / forced-exits.
Whenever possible it avoids full-reprocessing / only uncompleted
transactions will be reprocessed. When the processor is running in
parallel with a Bevy App, processor asset writes block Bevy App asset
reads. Reading metadata + asset bytes is guaranteed to be transactional
/ correctly paired.
* **Portable / Run anywhere / Database-free**: The processor does not
rely on an in-memory database (although it uses some database techniques
for reliability). This is important because pretty much all in-memory
databases have unsupported platforms or build complications.
* **Configure Processor Defaults Per File Type**: You can say "use this
processor for all files of this type".
* **Custom Processors**: The `Processor` trait is flexible and
unopinionated. It can be implemented by downstream plugins.
* **LoadAndSave Processors**: Most asset processing scenarios can be
expressed as "run AssetLoader A, save the results using AssetSaver X,
and then load the result using AssetLoader B". For example, load this
png image using `PngImageLoader`, which produces an `Image` asset and
then save it using `CompressedImageSaver` (which also produces an
`Image` asset, but in a compressed format), which takes an `Image` asset
as input. This means if you have an `AssetLoader` for an asset, you are
already half way there! It also means that you can share AssetSavers
across multiple loaders. Because `CompressedImageSaver` accepts Bevy's
generic Image asset as input, it means you can also use it with some
future `JpegImageLoader`.
* **Loader and Saver Settings**: Asset Loaders and Savers can now define
their own settings types, which are passed in as input when an asset is
loaded / saved. Each asset can define its own settings.
* **Asset `.meta` files**: configure asset loaders, their settings,
enable/disable processing, and configure processor settings
* **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex:
if an asset contains a `Handle<Image>`) are tracked by the asset server.
An event is emitted when an asset and all of its dependencies have been
loaded
* **Unprocessed Asset Loading**: Assets do not require preprocessing.
They can be loaded directly. A processed asset is just a "normal" asset
with some extra metadata. Asset Loaders don't need to know or care about
whether or not an asset was processed.
* **Async Asset IO**: Asset readers/writers use async non-blocking
interfaces. Note that because Rust doesn't yet support async traits,
there is a bit of manual Boxing / Future boilerplate. This will
hopefully be removed in the near future when Rust gets async traits.
* **Pluggable Asset Readers and Writers**: Arbitrary asset source
readers/writers are supported, both by the processor and the asset
server.
* **Better Asset Handles**
* **Single Arc Tree**: Asset Handles now use a single arc tree that
represents the lifetime of the asset. This makes their implementation
simpler, more efficient, and allows us to cheaply attach metadata to
handles. Ex: the AssetPath of a handle is now directly accessible on the
handle itself!
* **Const Typed Handles**: typed handles can be constructed in a const
context. No more weird "const untyped converted to typed at runtime"
patterns!
* **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed
`Handle<T>` is now much smaller in memory and `AssetId<T>` is even
smaller.
* **Weak Handle Usage Reduction**: In general Handles are now considered
to be "strong". Bevy features that previously used "weak `Handle<T>`"
have been ported to `AssetId<T>`, which makes it statically clear that
the features do not hold strong handles (while retaining strong type
information). Currently Handle::Weak still exists, but it is very
possible that we can remove that entirely.
* **Efficient / Dense Asset Ids**: Assets now have efficient dense
runtime asset ids, which means we can avoid expensive hash lookups.
Assets are stored in Vecs instead of HashMaps. There are now typed and
untyped ids, which means we no longer need to store dynamic type
information in the ID for typed handles. "AssetPathId" (which was a
nightmare from a performance and correctness standpoint) has been
entirely removed in favor of dense ids (which are retrieved for a path
on load)
* **Direct Asset Loading, with Dependency Tracking**: Assets that are
defined at runtime can still have their dependencies tracked by the
Asset Server (ex: if you create a material at runtime, you can still
wait for its textures to load). This is accomplished via the (currently
optional) "asset dependency visitor" trait. This system can also be used
to define a set of assets to load, then wait for those assets to load.
* **Async folder loading**: Folder loading also uses this system and
immediately returns a handle to the LoadedFolder asset, which means
folder loading no longer blocks on directory traversals.
* **Improved Loader Interface**: Loaders now have a specific "top level
asset type", which makes returning the top-level asset simpler and
statically typed.
* **Basic Image Settings and Processing**: Image assets can now be
processed into the gpu-friendly Basic Universal format. The ImageLoader
now has a setting to define what format the image should be loaded as.
Note that this is just a minimal MVP ... plenty of additional work to do
here. To demo this, enable the `basis-universal` feature and turn on
asset processing.
* **Simpler Audio Play / AudioSink API**: Asset handle providers are
cloneable, which means the Audio resource can mint its own handles. This
means you can now do `let sink_handle = audio.play(music)` instead of
`let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that
this might still be replaced by
https://github.com/bevyengine/bevy/pull/8424.
**Removed Handle Casting From Engine Features**: Ex: FontAtlases no
longer use casting between handle types
## Using The New Asset System
### Normal Unprocessed Asset Loading
By default the `AssetPlugin` does not use processing. It behaves pretty
much the same way as the old system.
If you are defining a custom asset, first derive `Asset`:
```rust
#[derive(Asset)]
struct Thing {
value: String,
}
```
Initialize the asset:
```rust
app.init_asset:<Thing>()
```
Implement a new `AssetLoader` for it:
```rust
#[derive(Default)]
struct ThingLoader;
#[derive(Serialize, Deserialize, Default)]
pub struct ThingSettings {
some_setting: bool,
}
impl AssetLoader for ThingLoader {
type Asset = Thing;
type Settings = ThingSettings;
fn load<'a>(
&'a self,
reader: &'a mut Reader,
settings: &'a ThingSettings,
load_context: &'a mut LoadContext,
) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> {
Box::pin(async move {
let mut bytes = Vec::new();
reader.read_to_end(&mut bytes).await?;
// convert bytes to value somehow
Ok(Thing {
value
})
})
}
fn extensions(&self) -> &[&str] {
&["thing"]
}
}
```
Note that this interface will get much cleaner once Rust gets support
for async traits. `Reader` is an async futures_io::AsyncRead. You can
stream bytes as they come in or read them all into a `Vec<u8>`,
depending on the context. You can use `let handle =
load_context.load(path)` to kick off a dependency load, retrieve a
handle, and register the dependency for the asset.
Then just register the loader in your Bevy app:
```rust
app.init_asset_loader::<ThingLoader>()
```
Now just add your `Thing` asset files into the `assets` folder and load
them like this:
```rust
fn system(asset_server: Res<AssetServer>) {
let handle = Handle<Thing> = asset_server.load("cool.thing");
}
```
You can check load states directly via the asset server:
```rust
if asset_server.load_state(&handle) == LoadState::Loaded { }
```
You can also listen for events:
```rust
fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) {
for event in events.iter() {
if event.is_loaded_with_dependencies(&handle) {
}
}
}
```
Note the new `AssetEvent::LoadedWithDependencies`, which only fires when
the asset is loaded _and_ all dependencies (and their dependencies) have
loaded.
Unlike the old asset system, for a given asset path all `Handle<T>`
values point to the same underlying Arc. This means Handles can cheaply
hold more asset information, such as the AssetPath:
```rust
// prints the AssetPath of the handle
info!("{:?}", handle.path())
```
### Processed Assets
Asset processing can be enabled via the `AssetPlugin`. When developing
Bevy Apps with processed assets, do this:
```rust
app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))
```
This runs the `AssetProcessor` in the background with hot-reloading. It
reads assets from the `assets` folder, processes them, and writes them
to the `.imported_assets` folder. Asset loads in the Bevy App will wait
for a processed version of the asset to become available. If an asset in
the `assets` folder changes, it will be reprocessed and hot-reloaded in
the Bevy App.
When deploying processed Bevy apps, do this:
```rust
app.add_plugins(DefaultPlugins.set(AssetPlugin::processed()))
```
This does not run the `AssetProcessor` in the background. It behaves
like `AssetPlugin::unprocessed()`, but reads assets from
`.imported_assets`.
When the `AssetProcessor` is running, it will populate sibling `.meta`
files for assets in the `assets` folder. Meta files for assets that do
not have a processor configured look like this:
```rust
(
meta_format_version: "1.0",
asset: Load(
loader: "bevy_render::texture::image_loader::ImageLoader",
settings: (
format: FromExtension,
),
),
)
```
This is metadata for an image asset. For example, if you have
`assets/my_sprite.png`, this could be the metadata stored at
`assets/my_sprite.png.meta`. Meta files are totally optional. If no
metadata exists, the default settings will be used.
In short, this file says "load this asset with the ImageLoader and use
the file extension to determine the image type". This type of meta file
is supported in all AssetPlugin modes. If in `Unprocessed` mode, the
asset (with the meta settings) will be loaded directly. If in
`ProcessedDev` mode, the asset file will be copied directly to the
`.imported_assets` folder. The meta will also be copied directly to the
`.imported_assets` folder, but with one addition:
```rust
(
meta_format_version: "1.0",
processed_info: Some((
hash: 12415480888597742505,
full_hash: 14344495437905856884,
process_dependencies: [],
)),
asset: Load(
loader: "bevy_render::texture::image_loader::ImageLoader",
settings: (
format: FromExtension,
),
),
)
```
`processed_info` contains `hash` (a direct hash of the asset and meta
bytes), `full_hash` (a hash of `hash` and the hashes of all
`process_dependencies`), and `process_dependencies` (the `path` and
`full_hash` of every process_dependency). A "process dependency" is an
asset dependency that is _directly_ used when processing the asset.
Images do not have process dependencies, so this is empty.
When the processor is enabled, you can use the `Process` metadata
config:
```rust
(
meta_format_version: "1.0",
asset: Process(
processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>",
settings: (
loader_settings: (
format: FromExtension,
),
saver_settings: (
generate_mipmaps: true,
),
),
),
)
```
This configures the asset to use the `LoadAndSave` processor, which runs
an AssetLoader and feeds the result into an AssetSaver (which saves the
given Asset and defines a loader to load it with). (for terseness
LoadAndSave will likely get a shorter/friendlier type name when [Stable
Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common
processor type, but arbitrary processors are supported.
`CompressedImageSaver` saves an `Image` in the Basis Universal format
and configures the ImageLoader to load it as basis universal. The
`AssetProcessor` will read this meta, run it through the LoadAndSave
processor, and write the basis-universal version of the image to
`.imported_assets`. The final metadata will look like this:
```rust
(
meta_format_version: "1.0",
processed_info: Some((
hash: 905599590923828066,
full_hash: 9948823010183819117,
process_dependencies: [],
)),
asset: Load(
loader: "bevy_render::texture::image_loader::ImageLoader",
settings: (
format: Format(Basis),
),
),
)
```
To try basis-universal processing out in Bevy examples, (for example
`sprite.rs`), change `add_plugins(DefaultPlugins)` to
`add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run
with the `basis-universal` feature enabled: `cargo run
--features=basis-universal --example sprite`.
To create a custom processor, there are two main paths:
1. Use the `LoadAndSave` processor with an existing `AssetLoader`.
Implement the `AssetSaver` trait, register the processor using
`asset_processor.register_processor::<LoadAndSave<ImageLoader,
CompressedImageSaver>>(image_saver.into())`.
2. Implement the `Process` trait directly and register it using:
`asset_processor.register_processor(thing_processor)`.
You can configure default processors for file extensions like this:
```rust
asset_processor.set_default_processor::<ThingProcessor>("thing")
```
There is one more metadata type to be aware of:
```rust
(
meta_format_version: "1.0",
asset: Ignore,
)
```
This will ignore the asset during processing / prevent it from being
written to `.imported_assets`.
The AssetProcessor stores a transaction log at `.imported_assets/log`
and uses it to gracefully recover from unexpected stops. This means you
can force-quit the processor (and Bevy Apps running the processor in
parallel) at arbitrary times!
`.imported_assets` is "local state". It should _not_ be checked into
source control. It should also be considered "read only". In practice,
you _can_ modify processed assets and processed metadata if you really
need to test something. But those modifications will not be represented
in the hashes of the assets, so the processed state will be "out of
sync" with the source assets. The processor _will not_ fix this for you.
Either revert the change after you have tested it, or delete the
processed files so they can be re-populated.
## Open Questions
There are a number of open questions to be discussed. We should decide
if they need to be addressed in this PR and if so, how we will address
them:
### Implied Dependencies vs Dependency Enumeration
There are currently two ways to populate asset dependencies:
* **Implied via AssetLoaders**: if an AssetLoader loads an asset (and
retrieves a handle), a dependency is added to the list.
* **Explicit via the optional Asset::visit_dependencies**: if
`server.load_asset(my_asset)` is called, it will call
`my_asset.visit_dependencies`, which will grab dependencies that have
been manually defined for the asset via the Asset trait impl (which can
be derived).
This means that defining explicit dependencies is optional for "loaded
assets". And the list of dependencies is always accurate because loaders
can only produce Handles if they register dependencies. If an asset was
loaded with an AssetLoader, it only uses the implied dependencies. If an
asset was created at runtime and added with
`asset_server.load_asset(MyAsset)`, it will use
`Asset::visit_dependencies`.
However this can create a behavior mismatch between loaded assets and
equivalent "created at runtime" assets if `Assets::visit_dependencies`
doesn't exactly match the dependencies produced by the AssetLoader. This
behavior mismatch can be resolved by completely removing "implied loader
dependencies" and requiring `Asset::visit_dependencies` to supply
dependency data. But this creates two problems:
* It makes defining loaded assets harder and more error prone: Devs must
remember to manually annotate asset dependencies with `#[dependency]`
when deriving `Asset`. For more complicated assets (such as scenes), the
derive likely wouldn't be sufficient and a manual `visit_dependencies`
impl would be required.
* Removes the ability to immediately kick off dependency loads: When
AssetLoaders retrieve a Handle, they also immediately kick off an asset
load for the handle, which means it can start loading in parallel
_before_ the asset finishes loading. For large assets, this could be
significant. (although this could be mitigated for processed assets if
we store dependencies in the processed meta file and load them ahead of
time)
### Eager ProcessorDev Asset Loading
I made a controversial call in the interest of fast startup times ("time
to first pixel") for the "processor dev mode configuration". When
initializing the AssetProcessor, current processed versions of unchanged
assets are yielded immediately, even if their dependencies haven't been
checked yet for reprocessing. This means that
non-current-state-of-filesystem-but-previously-valid assets might be
returned to the App first, then hot-reloaded if/when their dependencies
change and the asset is reprocessed.
Is this behavior desirable? There is largely one alternative: do not
yield an asset from the processor to the app until all of its
dependencies have been checked for changes. In some common cases (load
dependency has not changed since last run) this will increase startup
time. The main question is "by how much" and is that slower startup time
worth it in the interest of only yielding assets that are true to the
current state of the filesystem. Should this be configurable? I'm
starting to think we should only yield an asset after its (historical)
dependencies have been checked for changes + processed as necessary, but
I'm curious what you all think.
### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs?
In this implementation AssetPaths are the only canonical asset
identifier (just like the previous Bevy Asset system and Godot). Moving
assets will result in re-scans (and currently reprocessing, although
reprocessing can easily be avoided with some changes). Asset
renames/moves will break code and assets that rely on specific paths,
unless those paths are fixed up.
Do we want / need "stable asset uuids"? Introducing them is very
possible:
1. Generate a UUID and include it in .meta files
2. Support UUID in AssetPath
3. Generate "asset indices" which are loaded on startup and map UUIDs to
paths.
4 (maybe). Consider only supporting UUIDs for processed assets so we can
generate quick-to-load indices instead of scanning meta files.
The main "pro" is that assets referencing UUIDs don't need to be
migrated when a path changes. The main "con" is that UUIDs cannot be
"lazily resolved" like paths. They need a full view of all assets to
answer the question "does this UUID exist". Which means UUIDs require
the AssetProcessor to fully finish startup scans before saying an asset
doesnt exist. And they essentially require asset pre-processing to use
in apps, because scanning all asset metadata files at runtime to resolve
a UUID is not viable for medium-to-large apps. It really requires a
pre-generated UUID index, which must be loaded before querying for
assets.
I personally think this should be investigated in a separate PR. Paths
aren't going anywhere ... _everyone_ uses filesystems (and
filesystem-like apis) to manage their asset source files. I consider
them permanent canonical asset information. Additionally, they behave
well for both processed and unprocessed asset modes. Given that Bevy is
supporting both, this feels like the right canonical ID to start with.
UUIDS (and maybe even other indexed-identifier types) can be added later
as necessary.
### Folder / File Naming Conventions
All asset processing config currently lives in the `.imported_assets`
folder. The processor transaction log is in `.imported_assets/log`.
Processed assets are added to `.imported_assets/Default`, which will
make migrating to processed asset profiles (ex: a
`.imported_assets/Mobile` profile) a non-breaking change. It also allows
us to create top-level files like `.imported_assets/log` without it
being interpreted as an asset. Meta files currently have a `.meta`
suffix. Do we like these names and conventions?
### Should the `AssetPlugin::processed_dev` configuration enable
`watch_for_changes` automatically?
Currently it does (which I think makes sense), but it does make it the
only configuration that enables watch_for_changes by default.
### Discuss on_loaded High Level Interface:
This PR includes a very rough "proof of concept" `on_loaded` system
adapter that uses the `LoadedWithDependencies` event in combination with
`asset_server.load_asset` dependency tracking to support this pattern
```rust
fn main() {
App::new()
.init_asset::<MyAssets>()
.add_systems(Update, on_loaded(create_array_texture))
.run();
}
#[derive(Asset, Clone)]
struct MyAssets {
#[dependency]
picture_of_my_cat: Handle<Image>,
#[dependency]
picture_of_my_other_cat: Handle<Image>,
}
impl FromWorld for ArrayTexture {
fn from_world(world: &mut World) -> Self {
picture_of_my_cat: server.load("meow.png"),
picture_of_my_other_cat: server.load("meeeeeeeow.png"),
}
}
fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) {
commands.spawn(SpriteBundle {
texture: my_assets.picture_of_my_cat.clone(),
..default()
});
commands.spawn(SpriteBundle {
texture: my_assets.picture_of_my_other_cat.clone(),
..default()
});
}
```
The implementation is _very_ rough. And it is currently unsafe because
`bevy_ecs` doesn't expose some internals to do this safely from inside
`bevy_asset`. There are plenty of unanswered questions like:
* "do we add a Loadable" derive? (effectively automate the FromWorld
implementation above)
* Should `MyAssets` even be an Asset? (largely implemented this way
because it elegantly builds on `server.load_asset(MyAsset { .. })`
dependency tracking).
We should think hard about what our ideal API looks like (and if this is
a pattern we want to support). Not necessarily something we need to
solve in this PR. The current `on_loaded` impl should probably be
removed from this PR before merging.
## Clarifying Questions
### What about Assets as Entities?
This Bevy Asset V2 proposal implementation initially stored Assets as
ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used
`Entity` as the asset id and Asset values were just ECS components.
There are plenty of compelling reasons to do this:
1. Easier to inline assets in Bevy Scenes (as they are "just" normal
entities + components)
2. More flexible queries: use the power of the ECS to filter assets (ex:
`Query<Mesh, With<Tree>>`).
3. Extensible. Users can add arbitrary component data to assets.
4. Things like "component visualization tools" work out of the box to
visualize asset data.
However Assets as Entities has a ton of caveats right now:
* We need to be able to allocate entity ids without a direct World
reference (aka rework id allocator in Entities ... i worked around this
in my prototypes by just pre allocating big chunks of entities)
* We want asset change events in addition to ECS change tracking ... how
do we populate them when mutations can come from anywhere? Do we use
Changed queries? This would require iterating over the change data for
all assets every frame. Is this acceptable or should we implement a new
"event based" component change detection option?
* Reconciling manually created assets with asset-system managed assets
has some nuance (ex: are they "loaded" / do they also have that
component metadata?)
* "how do we handle "static" / default entity handles" (ties in to the
Entity Indices discussion:
https://github.com/bevyengine/bevy/discussions/8319). This is necessary
for things like "built in" assets and default handles in things like
SpriteBundle.
* Storing asset information as a component makes it easy to "invalidate"
asset state by removing the component (or forcing modifications).
Ideally we have ways to lock this down (some combination of Rust type
privacy and ECS validation)
In practice, how we store and identify assets is a reasonably
superficial change (porting off of Assets as Entities and implementing
dedicated storage + ids took less than a day). So once we sort out the
remaining challenges the flip should be straightforward. Additionally, I
do still have "Assets as Entities" in my commit history, so we can reuse
that work. I personally think "assets as entities" is a good endgame,
but it also doesn't provide _significant_ value at the moment and it
certainly isn't ready yet with the current state of things.
### Why not Distill?
[Distill](https://github.com/amethyst/distill) is a high quality fully
featured asset system built in Rust. It is very natural to ask "why not
just use Distill?".
It is also worth calling out that for awhile, [we planned on adopting
Distill / I signed off on
it](https://github.com/bevyengine/bevy/issues/708).
However I think Bevy has a number of constraints that make Distill
adoption suboptimal:
* **Architectural Simplicity:**
* Distill's processor requires an in-memory database (lmdb) and RPC
networked API (using Cap'n Proto). Each of these introduces API
complexity that increases maintenance burden and "code grokability".
Ignoring tests, documentation, and examples, Distill has 24,237 lines of
Rust code (including generated code for RPC + database interactions). If
you ignore generated code, it has 11,499 lines.
* Bevy builds the AssetProcessor and AssetServer using pluggable
AssetReader/AssetWriter Rust traits with simple io interfaces. They do
not necessitate databases or RPC interfaces (although Readers/Writers
could use them if that is desired). Bevy Asset V2 (at the time of
writing this PR) is 5,384 lines of Rust code (ignoring tests,
documentation, and examples). Grain of salt: Distill does have more
features currently (ex: Asset Packing, GUIDS, remote-out-of-process
asset processor). I do plan to implement these features in Bevy Asset V2
and I personally highly doubt they will meaningfully close the 6115
lines-of-code gap.
* This complexity gap (which while illustrated by lines of code, is much
bigger than just that) is noteworthy to me. Bevy should be hackable and
there are pillars of Distill that are very hard to understand and
extend. This is a matter of opinion (and Bevy Asset V2 also has
complicated areas), but I think Bevy Asset V2 is much more approachable
for the average developer.
* Necessary disclaimer: counting lines of code is an extremely rough
complexity metric. Read the code and form your own opinions.
* **Optional Asset Processing:** Not all Bevy Apps (or Bevy App
developers) need / want asset preprocessing. Processing increases the
complexity of the development environment by introducing things like
meta files, imported asset storage, running processors in the
background, waiting for processing to finish, etc. Distill _requires_
preprocessing to work. With Bevy Asset V2 processing is fully opt-in.
The AssetServer isn't directly aware of asset processors at all.
AssetLoaders only care about converting bytes to runtime Assets ... they
don't know or care if the bytes were pre-processed or not. Processing is
"elegantly" (forgive my self-congratulatory phrasing) layered on top and
builds on the existing Asset system primitives.
* **Direct Filesystem Access to Processed Asset State:** Distill stores
processed assets in a database. This makes debugging / inspecting the
processed outputs harder (either requires special tooling to query the
database or they need to be "deployed" to be inspected). Bevy Asset V2,
on the other hand, stores processed assets in the filesystem (by default
... this is configurable). This makes interacting with the processed
state more natural. Note that both Godot and Unity's new asset system
store processed assets in the filesystem.
* **Portability**: Because Distill's processor uses lmdb and RPC
networking, it cannot be run on certain platforms (ex: lmdb is a
non-rust dependency that cannot run on the web, some platforms don't
support running network servers). Bevy should be able to process assets
everywhere (ex: run the Bevy Editor on the web, compile + process
shaders on mobile, etc). Distill does partially mitigate this problem by
supporting "streaming" assets via the RPC protocol, but this is not a
full solve from my perspective. And Bevy Asset V2 can (in theory) also
stream assets (without requiring RPC, although this isn't implemented
yet)
Note that I _do_ still think Distill would be a solid asset system for
Bevy. But I think the approach in this PR is a better solve for Bevy's
specific "asset system requirements".
### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the
point?
"True async file io" has limited / spotty platform support. async-fs
(and the rust async ecosystem generally ... ex Tokio) currently use
async wrappers over std::fs that offload blocking requests to separate
threads. This may feel unsatisfying, but it _does_ still provide value
because it prevents our task pools from blocking on file system
operations (which would prevent progress when there are many tasks to
do, but all threads in a pool are currently blocking on file system
ops).
Additionally, using async APIs for our AssetReaders and AssetWriters
also provides value because we can later add support for "true async
file io" for platforms that support it. _And_ we can implement other
"true async io" asset backends (such as networked asset io).
## Draft TODO
- [x] Fill in missing filesystem event APIs: file removed event (which
is expressed as dangling RenameFrom events in some cases), file/folder
renamed event
- [x] Assets without loaders are not moved to the processed folder. This
breaks things like referenced `.bin` files for GLTFs. This should be
configurable per-non-asset-type.
- [x] Initial implementation of Reflect and FromReflect for Handle. The
"deserialization" parity bar is low here as this only worked with static
UUIDs in the old impl ... this is a non-trivial problem. Either we add a
Handle::AssetPath variant that gets "upgraded" to a strong handle on
scene load or we use a separate AssetRef type for Bevy scenes (which is
converted to a runtime Handle on load). This deserves its own discussion
in a different pr.
- [x] Populate read_asset_bytes hash when run by the processor (a bit of
a special case .. when run by the processor the processed meta will
contain the hash so we don't need to compute it on the spot, but we
don't want/need to read the meta when run by the main AssetServer)
- [x] Delay hot reloading: currently filesystem events are handled
immediately, which creates timing issues in some cases. For example hot
reloading images can sometimes break because the image isn't finished
writing. We should add a delay, likely similar to the [implementation in
this PR](https://github.com/bevyengine/bevy/pull/8503).
- [x] Port old platform-specific AssetIo implementations to the new
AssetReader interface (currently missing Android and web)
- [x] Resolve on_loaded unsafety (either by removing the API entirely or
removing the unsafe)
- [x] Runtime loader setting overrides
- [x] Remove remaining unwraps that should be error-handled. There are
number of TODOs here
- [x] Pretty AssetPath Display impl
- [x] Document more APIs
- [x] Resolve spurious "reloading because it has changed" events (to
repro run load_gltf with `processed_dev()`)
- [x] load_dependency hot reloading currently only works for processed
assets. If processing is disabled, load_dependency changes are not hot
reloaded.
- [x] Replace AssetInfo dependency load/fail counters with
`loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from
(potentially) breaking counters. Storing this will also enable
"dependency reloaded" events (see [Next Steps](#next-steps))
- [x] Re-add filesystem watcher cargo feature gate (currently it is not
optional)
- [ ] Migration Guide
- [ ] Changelog
## Followup TODO
- [ ] Replace "eager unchanged processed asset loading" behavior with
"don't returned unchanged processed asset until dependencies have been
checked".
- [ ] Add true `Ignore` AssetAction that does not copy the asset to the
imported_assets folder.
- [ ] Finish "live asset unloading" (ex: free up CPU asset memory after
uploading an image to the GPU), rethink RenderAssets, and port renderer
features. The `Assets` collection uses `Option<T>` for asset storage to
support its removal. (1) the Option might not actually be necessary ...
might be able to just remove from the collection entirely (2) need to
finalize removal apis
- [ ] Try replacing the "channel based" asset id recycling with
something a bit more efficient (ex: we might be able to use raw atomic
ints with some cleverness)
- [ ] Consider adding UUIDs to processed assets (scoped just to helping
identify moved assets ... not exposed to load queries ... see [Next
Steps](#next-steps))
- [ ] Store "last modified" source asset and meta timestamps in
processed meta files to enable skipping expensive hashing when the file
wasn't changed
- [ ] Fix "slow loop" handle drop fix
- [ ] Migrate to TypeName
- [x] Handle "loader preregistration". See #9429
## Next Steps
* **Configurable per-type defaults for AssetMeta**: It should be
possible to add configuration like "all png image meta should default to
using nearest sampling" (currently this hard-coded per-loader/processor
Settings::default() impls). Also see the "Folder Meta" bullet point.
* **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical
asset ids" discussion in [Open Questions](#open-questions) and the
relevant bullet point in [Draft TODO](#draft-todo). Even without
canonical ids, folder renames could avoid reprocessing in some cases.
* **Multiple Asset Sources**: Expand AssetPath to support "asset source
names" and support multiple AssetReaders in the asset server (ex:
`webserver://some_path/image.png` backed by an Http webserver
AssetReader). The "default" asset reader would use normal
`some_path/image.png` paths. Ideally this works in combination with
multiple AssetWatchers for hot-reloading
* **Stable Type Names**: this pr removes the TypeUuid requirement from
assets in favor of `std::any::type_name`. This makes defining assets
easier (no need to generate a new uuid / use weird proc macro syntax).
It also makes reading meta files easier (because things have "friendly
names"). We also use type names for components in scene files. If they
are good enough for components, they are good enough for assets. And
consistency across Bevy pillars is desirable. However,
`std::any::type_name` is not guaranteed to be stable (although in
practice it is). We've developed a [stable type
path](https://github.com/bevyengine/bevy/pull/7184) to resolve this,
which should be adopted when it is ready.
* **Command Line Interface**: It should be possible to run the asset
processor in a separate process from the command line. This will also
require building a network-server-backed AssetReader to communicate
between the app and the processor. We've been planning to build a "bevy
cli" for awhile. This seems like a good excuse to build it.
* **Asset Packing**: This is largely an additive feature, so it made
sense to me to punt this until we've laid the foundations in this PR.
* **Per-Platform Processed Assets**: It should be possible to generate
assets for multiple platforms by supporting multiple "processor
profiles" per asset (ex: compress with format X on PC and Y on iOS). I
think there should probably be arbitrary "profiles" (which can be
separate from actual platforms), which are then assigned to a given
platform when generating the final asset distribution for that platform.
Ex: maybe devs want a "Mobile" profile that is shared between iOS and
Android. Or a "LowEnd" profile shared between web and mobile.
* **Versioning and Migrations**: Assets, Loaders, Savers, and Processors
need to have versions to determine if their schema is valid. If an asset
/ loader version is incompatible with the current version expected at
runtime, the processor should be able to migrate them. I think we should
try using Bevy Reflect for this, as it would allow us to load the old
version as a dynamic Reflect type without actually having the old Rust
type. It would also allow us to define "patches" to migrate between
versions (Bevy Reflect devs are currently working on patching). The
`.meta` file already has its own format version. Migrating that to new
versions should also be possible.
* **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write
type) currently used by AssetPath can still result in String clones that
aren't actually necessary (cloning an Owned Cow clones the contents).
Bevy's asset system requires cloning AssetPaths in a number of places,
which result in actual clones of the internal Strings. This is not
efficient. AssetPath internals should be reworked to exhibit truer
cow-like-behavior that reduces String clones to the absolute minimum.
* **Consider processor-less processing**: In theory the AssetServer
could run processors "inline" even if the background AssetProcessor is
disabled. If we decide this is actually desirable, we could add this.
But I don't think its a priority in the short or medium term.
* **Pre-emptive dependency loading**: We could encode dependencies in
processed meta files, which could then be used by the Asset Server to
kick of dependency loads as early as possible (prior to starting the
actual asset load). Is this desirable? How much time would this save in
practice?
* **Optimize Processor With UntypedAssetIds**: The processor exclusively
uses AssetPath to identify assets currently. It might be possible to
swap these out for UntypedAssetIds in some places, which are smaller /
cheaper to hash and compare.
* **One to Many Asset Processing**: An asset source file that produces
many assets currently must be processed into a single "processed" asset
source. If labeled assets can be written separately they can each have
their own configured savers _and_ they could be loaded more granularly.
Definitely worth exploring!
* **Automatically Track "Runtime-only" Asset Dependencies**: Right now,
tracking "created at runtime" asset dependencies requires adding them
via `asset_server.load_asset(StandardMaterial::default())`. I think with
some cleverness we could also do this for
`materials.add(StandardMaterial::default())`, making tracking work
"everywhere". There are challenges here relating to change detection /
ensuring the server is made aware of dependency changes. This could be
expensive in some cases.
* **"Dependency Changed" events**: Some assets have runtime artifacts
that need to be re-generated when one of their dependencies change (ex:
regenerate a material's bind group when a Texture needs to change). We
are generating the dependency graph so we can definitely produce these
events. Buuuuut generating these events will have a cost / they could be
high frequency for some assets, so we might want this to be opt-in for
specific cases.
* **Investigate Storing More Information In Handles**: Handles can now
store arbitrary information, which makes it cheaper and easier to
access. How much should we move into them? Canonical asset load states
(via atomics)? (`handle.is_loaded()` would be very cool). Should we
store the entire asset and remove the `Assets<T>` collection?
(`Arc<RwLock<Option<Image>>>`?)
* **Support processing and loading files without extensions**: This is a
pretty arbitrary restriction and could be supported with very minimal
changes.
* **Folder Meta**: It would be nice if we could define per folder
processor configuration defaults (likely in a `.meta` or `.folder_meta`
file). Things like "default to linear filtering for all Images in this
folder".
* **Replace async_broadcast with event-listener?** This might be
approximately drop-in for some uses and it feels more light weight
* **Support Running the AssetProcessor on the Web**: Most of the hard
work is done here, but there are some easy straggling TODOs (make the
transaction log an interface instead of a direct file writer so we can
write a web storage backend, implement an AssetReader/AssetWriter that
reads/writes to something like LocalStorage).
* **Consider identifying and preventing circular dependencies**: This is
especially important for "processor dependencies", as processing will
silently never finish in these cases.
* **Built-in/Inlined Asset Hot Reloading**: This PR regresses
"built-in/inlined" asset hot reloading (previously provided by the
DebugAssetServer). I'm intentionally punting this because I think it can
be cleanly implemented with "multiple asset sources" by registering a
"debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset
paths) in combination with an AssetWatcher for that asset source and
support for "manually loading pats with asset bytes instead of
AssetReaders". The old DebugAssetServer was quite nasty and I'd love to
avoid that hackery going forward.
* **Investigate ways to remove double-parsing meta files**: Parsing meta
files currently involves parsing once with "minimal" versions of the
meta file to extract the type name of the loader/processor config, then
parsing again to parse the "full" meta. This is suboptimal. We should be
able to define custom deserializers that (1) assume the loader/processor
type name comes first (2) dynamically looks up the loader/processor
registrations to deserialize settings in-line (similar to components in
the bevy scene format). Another alternative: deserialize as dynamic
Reflect objects and then convert.
* **More runtime loading configuration**: Support using the Handle type
as a hint to select an asset loader (instead of relying on AssetPath
extensions)
* **More high level Processor trait implementations**: For example, it
might be worth adding support for arbitrary chains of "asset transforms"
that modify an in-memory asset representation between loading and
saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by
a `flip_normals` transform, then save the mesh to an efficient
compressed format).
* **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO
item](#draft-todo) for context)
* **Explore High Level Load Interfaces**: See [this
discussion](#discuss-on_loaded-high-level-interface) for one prototype.
* **Asset Streaming**: It would be great if we could stream Assets (ex:
stream a long video file piece by piece)
* **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than
they need to be because they have a Uuid enum variant. If we implement
an "id exchanging" system that trades Uuids for "efficient runtime ids",
we can cut down on the size of AssetIds, making them more efficient.
This has some open design questions, such as how to spawn entities with
"default" handle values (as these wouldn't have access to the exchange
api in the current system).
* **Asset Path Fixup Tooling**: Assets that inline asset paths inside
them will break when an asset moves. The asset system provides the
functionality to detect when paths break. We should build a framework
that enables formats to define "path migrations". This is especially
important for scene files. For editor-generated files, we should also
consider using UUIDs (see other bullet point) to avoid the need to
migrate in these cases.
---------
Co-authored-by: BeastLe9enD <beastle9end@outlook.de>
Co-authored-by: Mike <mike.hsu@gmail.com>
Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
# Objective
fix #8185, #6710
replace #7005 (closed)
rgb and rgba 16 bit textures currently default to `Rgba16Uint`, the more
common use is `Rgba16Unorm`, which also matches the default type of rgb8
and rgba8 textures.
## Solution
Change default to `Rgba16Unorm`
# Objective
Bevy currently crashes when meshes with different vertex counts for
attributes are provided.
## Solution
Instead of crashing we can warn and take the min length of all the given
attributes.
# Objective
- Fixes#9244.
## Solution
- Changed the `(Into)SystemSetConfigs` traits and structs be more like
the `(Into)SystemConfigs` traits and structs.
- Replaced uses of `IntoSystemSetConfig` with `IntoSystemSetConfigs`
- Added generic `ItemConfig` and `ItemConfigs` types.
- Changed `SystemConfig(s)` and `SystemSetConfig(s)` to be type aliases
to `ItemConfig(s)`.
- Added generic `process_configs` to `ScheduleGraph`.
- Changed `configure_sets_inner` and `add_systems_inner` to reuse
`process_configs`.
---
## Changelog
- Added `run_if` to `IntoSystemSetConfigs`
- Deprecated `Schedule::configure_set` and `App::configure_set`
- Removed `IntoSystemSetConfig`
## Migration Guide
- Use `App::configure_sets` instead of `App::configure_set`
- Use `Schedule::configure_sets` instead of `Schedule::configure_set`
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
This PR aims to fix a handful of problems with the `SpatialBundle` docs:
The docs describe the role of the single components of the bundle,
overshadowing the purpose of `SpatialBundle` itself. Also, those items
may be added, removed or changed over time, as it happened with #9497,
requiring a higher maintenance effort, which will often result in
errors, as it happened.
## Solution
Just describe the role of `SpatialBundle` and of the transform and
visibility concepts, without mentioning the specific component types.
Since the bundle has public fields, the reader can easily click them and
read the documentation if they need to know more. I removed the mention
of numbers of components since they were four, now they are five, and
who knows how many they will be in the future. In this process, I
removed the bullet points, which are no longer needed, and were
contextually wrong in the first place, since they were meant to list the
components, but ended up describing use-cases and requirements for
hierarchies.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Supercedes #8872
- Improve sprite rendering performance after the regression in #9236
## Solution
- Use an instance-rate vertex buffer to store per-instance data.
- Store color, UV offset and scale, and a transform per instance.
- Convert Sprite rect, custom_size, anchor, and flip_x/_y to an affine
3x4 matrix and store the transpose of that in the per-instance data.
This is similar to how MeshUniform uses transpose affine matrices.
- Use a special index buffer that has batches of 6 indices referencing 4
vertices. The lower 2 bits indicate the x and y of a quad such that the
corners are:
```
10 11
00 01
```
UVs are implicit but get modified by UV offset and scale The remaining
upper bits contain the instance index.
## Benchmarks
I will compare versus `main` before #9236 because the results should be
as good as or faster than that. Running `bevymark -- 10000 16` on an M1
Max with `main` at `e8b38925` in yellow, this PR in red:
![Screenshot 2023-08-27 at 18 44
10](https://github.com/bevyengine/bevy/assets/302146/bdc5c929-d547-44bb-b519-20dce676a316)
Looking at the median frame times, that's a 37% reduction from before.
---
## Changelog
- Changed: Improved sprite rendering performance by leveraging an
instance-rate vertex buffer.
---------
Co-authored-by: Giacomo Stevanato <giaco.stevanato@gmail.com>
# Objective
Fix#8267.
Fixes half of #7840.
The `ComputedVisibility` component contains two flags: hierarchy
visibility, and view visibility (whether its visible to any cameras).
Due to the modular and open-ended way that view visibility is computed,
it triggers change detection every single frame, even when the value
does not change. Since hierarchy visibility is stored in the same
component as view visibility, this means that change detection for
inherited visibility is completely broken.
At the company I work for, this has become a real issue. We are using
change detection to only re-render scenes when necessary. The broken
state of change detection for computed visibility means that we have to
to rely on the non-inherited `Visibility` component for now. This is
workable in the early stages of our project, but since we will
inevitably want to use the hierarchy, we will have to either:
1. Roll our own solution for computed visibility.
2. Fix the issue for everyone.
## Solution
Split the `ComputedVisibility` component into two: `InheritedVisibilty`
and `ViewVisibility`.
This allows change detection to behave properly for
`InheritedVisibility`.
View visiblity is still erratic, although it is less useful to be able
to detect changes
for this flavor of visibility.
Overall, this actually simplifies the API. Since the visibility system
consists of
self-explaining components, it is much easier to document the behavior
and usage.
This approach is more modular and "ECS-like" -- one could
strip out the `ViewVisibility` component entirely if it's not needed,
and rely only on inherited visibility.
---
## Changelog
- `ComputedVisibility` has been removed in favor of:
`InheritedVisibility` and `ViewVisiblity`.
## Migration Guide
The `ComputedVisibilty` component has been split into
`InheritedVisiblity` and
`ViewVisibility`. Replace any usages of
`ComputedVisibility::is_visible_in_hierarchy`
with `InheritedVisibility::get`, and replace
`ComputedVisibility::is_visible_in_view`
with `ViewVisibility::get`.
```rust
// Before:
commands.spawn(VisibilityBundle {
visibility: Visibility::Inherited,
computed_visibility: ComputedVisibility::default(),
});
// After:
commands.spawn(VisibilityBundle {
visibility: Visibility::Inherited,
inherited_visibility: InheritedVisibility::default(),
view_visibility: ViewVisibility::default(),
});
```
```rust
// Before:
fn my_system(q: Query<&ComputedVisibilty>) {
for vis in &q {
if vis.is_visible_in_hierarchy() {
// After:
fn my_system(q: Query<&InheritedVisibility>) {
for inherited_visibility in &q {
if inherited_visibility.get() {
```
```rust
// Before:
fn my_system(q: Query<&ComputedVisibilty>) {
for vis in &q {
if vis.is_visible_in_view() {
// After:
fn my_system(q: Query<&ViewVisibility>) {
for view_visibility in &q {
if view_visibility.get() {
```
```rust
// Before:
fn my_system(mut q: Query<&mut ComputedVisibilty>) {
for vis in &mut q {
vis.set_visible_in_view();
// After:
fn my_system(mut q: Query<&mut ViewVisibility>) {
for view_visibility in &mut q {
view_visibility.set();
```
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
# Objective
Make it easier to create bounding boxes in user code by providing a
constructor that computes a box surrounding an arbitrary number of
points.
## Solution
Add `Aabb::enclosing`, which accepts iterators, slices, or arrays.
---------
Co-authored-by: Tristan Guichaoua <33934311+tguichaoua@users.noreply.github.com>
# Objective
- The current `EventReader::iter` has been determined to cause confusion
among new Bevy users. It was suggested by @JoJoJet to rename the method
to better clarify its usage.
- Solves #9624
## Solution
- Rename `EventReader::iter` to `EventReader::read`.
- Rename `EventReader::iter_with_id` to `EventReader::read_with_id`.
- Rename `ManualEventReader::iter` to `ManualEventReader::read`.
- Rename `ManualEventReader::iter_with_id` to
`ManualEventReader::read_with_id`.
---
## Changelog
- `EventReader::iter` has been renamed to `EventReader::read`.
- `EventReader::iter_with_id` has been renamed to
`EventReader::read_with_id`.
- `ManualEventReader::iter` has been renamed to
`ManualEventReader::read`.
- `ManualEventReader::iter_with_id` has been renamed to
`ManualEventReader::read_with_id`.
- Deprecated `EventReader::iter`
- Deprecated `EventReader::iter_with_id`
- Deprecated `ManualEventReader::iter`
- Deprecated `ManualEventReader::iter_with_id`
## Migration Guide
- Existing usages of `EventReader::iter` and `EventReader::iter_with_id`
will have to be changed to `EventReader::read` and
`EventReader::read_with_id` respectively.
- Existing usages of `ManualEventReader::iter` and
`ManualEventReader::iter_with_id` will have to be changed to
`ManualEventReader::read` and `ManualEventReader::read_with_id`
respectively.
# Objective
As far as I can tell, this is no longer needed since the switch to
fancier shader imports via `naga_oil`.
This shouldn't have any affect on compile times because it's in our tree
from `naga_oil`, `tracing-subscriber`, and `rodio`.
# Objective
- Move schedule name into `Schedule` to allow the schedule name to be
used for errors and tracing in Schedule methods
- Fixes#9510
## Solution
- Move label onto `Schedule` and adjust api's on `World` and `Schedule`
to not pass explicit label where it makes sense to.
- add name to errors and tracing.
- `Schedule::new` now takes a label so either add the label or use
`Schedule::default` which uses a default label. `default` is mostly used
in doc examples and tests.
---
## Changelog
- move label onto `Schedule` to improve error message and logging for
schedules.
## Migration Guide
`Schedule::new` and `App::add_schedule`
```rust
// old
let schedule = Schedule::new();
app.add_schedule(MyLabel, schedule);
// new
let schedule = Schedule::new(MyLabel);
app.add_schedule(schedule);
```
if you aren't using a label and are using the schedule struct directly
you can use the default constructor.
```rust
// old
let schedule = Schedule::new();
schedule.run(world);
// new
let schedule = Schedule::default();
schedule.run(world);
```
`Schedules:insert`
```rust
// old
let schedule = Schedule::new();
schedules.insert(MyLabel, schedule);
// new
let schedule = Schedule::new(MyLabel);
schedules.insert(schedule);
```
`World::add_schedule`
```rust
// old
let schedule = Schedule::new();
world.add_schedule(MyLabel, schedule);
// new
let schedule = Schedule::new(MyLabel);
world.add_schedule(schedule);
```
# Objective
These new defaults match what is used by `Camera2dBundle::default()`,
removing a potential footgun from overriding a field in the projection
component of the bundle.
## Solution
Adjusted the near clipping plane of `OrthographicProjection::default()`
to `-1000.`.
---
## Changelog
Changed: `OrthographicProjection::default()` now matches the value used
in `Camera2dBundle::default()`
## Migration Guide
Workarounds used to keep the projection consistent with the bundle
defaults are no longer required. Meanwhile, uses of
`OrthographicProjection` in 2D scenes may need to be adjusted; the
`near` clipping plane default was changed from `0.0` to `-1000.0`.
# Objective
This PR's first aim is to fix a mistake in `HalfSpace`'s documentation.
When defining a `Frustum` myself in bevy_basic_portals, I realised that
the "distance" of the `HalfSpace` is not, as the current doc defines,
the "distance from the origin along the normal", but actually the
opposite of that.
See the example I gave in this PR.
This means one of two things:
1. The documentation about `HalfSpace` is wrong (it is either way
because of the `n.p + d > 0` formula given later anyway, which is how it
behaves, but in that formula `d` is indeed the opposite of the "distance
from the origin along the normal", otherwise it should be `n.p > d`)
2. The distance is supposed to be the "distance from the origin along
the normal" but when used in a Frustum it's used as the opposite, and it
is a mistake
3. Same as 2, but it is somehow intended
Since I think `HalfSpace` is only used for `Frustum`, and it's easier to
fix documentation than code, I assumed for this PR we're in case number
1. If we're in case number 3, the documentation of `Frustum` needs to
change, and in case number 2, the code needs to be fixed.
While I was at it, I also :
- Tried to improve the documentation for `Frustum`, `Aabb`, and
`VisibilitySystems`, among others, since they're all related to
`Frustum`.
- Fixed documentation about frustum culling not applying to 2d objects,
which is not true since https://github.com/bevyengine/bevy/pull/7885
## Remarks and questions
- What about a `HalfSpace` with an infinite distance, is it allowed and
does it represents the whole space? If so it should probably be
mentioned.
- I referenced the `update_frusta` system in
`bevy_render::view::visibility` directly instead of referencing its
system set, should I reference the system set instead? It's a bit
annoying since it's in 3 sets.
- `visibility_propagate` is not public for some reason, I think it
probably should be, but for now I only documented its system set, should
I make it public? I don't think that would count as a breaking change?
- Why is `Aabb` inserted by a system, with `NoFrustumCulling` as an
opt-out, instead of having it inserted by default in `PbrBundle` for
example and then the system calculating it when it's added? Is it
because there is still no way to have an optional component inside a
bundle?
---------
Co-authored-by: SpecificProtagonist <vincentjunge@posteo.net>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
This is a continuation of this PR: #8062
# Objective
- Reorder render schedule sets to allow data preparation when phase item
order is known to support improved batching
- Part of the batching/instancing etc plan from here:
https://github.com/bevyengine/bevy/issues/89#issuecomment-1379249074
- The original idea came from @inodentry and proved to be a good one.
Thanks!
- Refactor `bevy_sprite` and `bevy_ui` to take advantage of the new
ordering
## Solution
- Move `Prepare` and `PrepareFlush` after `PhaseSortFlush`
- Add a `PrepareAssets` set that runs in parallel with other systems and
sets in the render schedule.
- Put prepare_assets systems in the `PrepareAssets` set
- If explicit dependencies are needed on Mesh or Material RenderAssets
then depend on the appropriate system.
- Add `ManageViews` and `ManageViewsFlush` sets between
`ExtractCommands` and Queue
- Move `queue_mesh*_bind_group` to the Prepare stage
- Rename them to `prepare_`
- Put systems that prepare resources (buffers, textures, etc.) into a
`PrepareResources` set inside `Prepare`
- Put the `prepare_..._bind_group` systems into a `PrepareBindGroup` set
after `PrepareResources`
- Move `prepare_lights` to the `ManageViews` set
- `prepare_lights` creates views and this must happen before `Queue`
- This system needs refactoring to stop handling all responsibilities
- Gather lights, sort, and create shadow map views. Store sorted light
entities in a resource
- Remove `BatchedPhaseItem`
- Replace `batch_range` with `batch_size` representing how many items to
skip after rendering the item or to skip the item entirely if
`batch_size` is 0.
- `queue_sprites` has been split into `queue_sprites` for queueing phase
items and `prepare_sprites` for batching after the `PhaseSort`
- `PhaseItem`s are still inserted in `queue_sprites`
- After sorting adjacent compatible sprite phase items are accumulated
into `SpriteBatch` components on the first entity of each batch,
containing a range of vertex indices. The associated `PhaseItem`'s
`batch_size` is updated appropriately.
- `SpriteBatch` items are then drawn skipping over the other items in
the batch based on the value in `batch_size`
- A very similar refactor was performed on `bevy_ui`
---
## Changelog
Changed:
- Reordered and reworked render app schedule sets. The main change is
that data is extracted, queued, sorted, and then prepared when the order
of data is known.
- Refactor `bevy_sprite` and `bevy_ui` to take advantage of the
reordering.
## Migration Guide
- Assets such as materials and meshes should now be created in
`PrepareAssets` e.g. `prepare_assets<Mesh>`
- Queueing entities to `RenderPhase`s continues to be done in `Queue`
e.g. `queue_sprites`
- Preparing resources (textures, buffers, etc.) should now be done in
`PrepareResources`, e.g. `prepare_prepass_textures`,
`prepare_mesh_uniforms`
- Prepare bind groups should now be done in `PrepareBindGroups` e.g.
`prepare_mesh_bind_group`
- Any batching or instancing can now be done in `Prepare` where the
order of the phase items is known e.g. `prepare_sprites`
## Next Steps
- Introduce some generic mechanism to ensure items that can be batched
are grouped in the phase item order, currently you could easily have
`[sprite at z 0, mesh at z 0, sprite at z 0]` preventing batching.
- Investigate improved orderings for building the MeshUniform buffer
- Implementing batching across the rest of bevy
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
# Objective
[Rust 1.72.0](https://blog.rust-lang.org/2023/08/24/Rust-1.72.0.html) is
now stable.
# Notes
- `let-else` formatting has arrived!
- I chose to allow `explicit_iter_loop` due to
https://github.com/rust-lang/rust-clippy/issues/11074.
We didn't hit any of the false positives that prevent compilation, but
fixing this did produce a lot of the "symbol soup" mentioned, e.g. `for
image in &mut *image_events {`.
Happy to undo this if there's consensus the other way.
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
- Fixes#9552
## Solution
- Only n_pixels bytes of data was being copied instead of 1 byte per
component, i.e. n_pixels * 4
---
## Changelog
- Fixed: loading of Rgb8 ktx2 files.
# Objective
Allow users to specify the power preference when selecting a wgpu
adapter, which is useful for testing or workaround purposes, and makes
the behaviour consistent with the already present check for
`WGPU_BACKEND`.
## Solution
In `WgpuSettings::default()`, allow users to specify the
`WGPU_POWER_PREF` to affect the wgpu adapter choice.
# Objective
- Significantly reduce the size of MeshUniform by only including
necessary data.
## Solution
Local to world, model transforms are affine. This means they only need a
4x3 matrix to represent them.
`MeshUniform` stores the current, and previous model transforms, and the
inverse transpose of the current model transform, all as 4x4 matrices.
Instead we can store the current, and previous model transforms as 4x3
matrices, and we only need the upper-left 3x3 part of the inverse
transpose of the current model transform. This change allows us to
reduce the serialized MeshUniform size from 208 bytes to 144 bytes,
which is over a 30% saving in data to serialize, and VRAM bandwidth and
space.
## Benchmarks
On an M1 Max, running `many_cubes -- sphere`, main is in yellow, this PR
is in red:
<img width="1484" alt="Screenshot 2023-08-11 at 02 36 43"
src="https://github.com/bevyengine/bevy/assets/302146/7d99c7b3-f2bb-4004-a8d0-4c00f755cb0d">
A reduction in frame time of ~14%.
---
## Changelog
- Changed: Redefined `MeshUniform` to improve performance by using 4x3
affine transforms and reconstructing 4x4 matrices in the shader. Helper
functions were added to `bevy_pbr::mesh_functions` to unpack the data.
`affine_to_square` converts the packed 4x3 in 3x4 matrix data to a 4x4
matrix. `mat2x4_f32_to_mat3x3` converts the 3x3 in mat2x4 + f32 matrix
data back into a 3x3.
## Migration Guide
Shader code before:
```
var model = mesh[instance_index].model;
```
Shader code after:
```
#import bevy_pbr::mesh_functions affine_to_square
var model = affine_to_square(mesh[instance_index].model);
```
# Objective
- When loading gltf files during app creation (for example using a
FromWorld impl and adding that as a resource), no loader was found.
- As the gltf loader can load compressed formats, it needs to know what
the GPU supports so it's not available at app creation time.
## Solution
alternative to #9426
- add functionality to preregister the loader. loading assets with
matching extensions will block until a real loader is registered.
- preregister "gltf" and "glb".
- prereigster image formats.
the way this is set up, if a set of extensions are all registered with a
single preregistration call, then later a loader is added that matches
some of the extensions, assets using the remaining extensions will then
fail. i think that should work well for image formats that we don't know
are supported until later.
# Objective
Bevy prefers `mod.rs` inside `module_name` files over `module_name.rs`
collocated with `module_name`. In `bevy_render`, it seems the `window`
modules didn't follow this convention
## Solution
- Follow the `mod.rs` convention.
# Objective
Update a camera's frustum only when needed.
- Maybe a performance gain from not having to compute frusta when not
needed, at the cost of change detection (?)
- Making "fighting" with `update_frusta` less tedious, see
https://github.com/bevyengine/bevy/issues/9077 and
https://discord.com/channels/691052431525675048/743663924229963868/1127566087966433322
## Solution
Add change detection filter for `GlobalTransform` or `T:
CameraProjection` in `update_frusta`, since those are the cases when the
frustum needs to be updated.
## Note
I don't think a migration guide and changelog are needed, but I'm not
100% sure, I could put something like "if you're fighting against
`update_frusta`, you can do it only when there is a change to
`GlobalTransform` or `CameraProjection` now", what do you think? It's
not really a breaking change with a normal use case.
naga and wgpu should polyfill WGSL instance_index functionality where it
is not available in GLSL. Until that is done, we can work around it in
bevy using a push constant which is converted to a uniform by naga and
wgpu.
# Objective
- Fixes#9375
## Solution
- Use a push constant to pass in the base instance to the shader on
WebGL2 so that base instance + gl_InstanceID is used to correctly
represent the instance index.
## TODO
- [ ] Benchmark vs per-object dynamic offset MeshUniform as this will
now push a uniform value per-draw as well as update the dynamic offset
per-batch.
- [x] Test on DX12 AMD/NVIDIA to check that this PR does not regress any
problems that were observed there. (@Elabajaba @robtfm were testing that
last time - help appreciated. <3 )
---
## Changelog
- Added: `bevy_render::instance_index` shader import which includes a
workaround for the lack of a WGSL `instance_index` polyfill for WebGL2
in naga and wgpu for the time being. It uses a push_constant which gets
converted to a plain uniform by naga and wgpu.
## Migration Guide
Shader code before:
```
struct Vertex {
@builtin(instance_index) instance_index: u32,
...
}
@vertex
fn vertex(vertex_no_morph: Vertex) -> VertexOutput {
...
var model = mesh[vertex_no_morph.instance_index].model;
```
After:
```
#import bevy_render::instance_index
struct Vertex {
@builtin(instance_index) instance_index: u32,
...
}
@vertex
fn vertex(vertex_no_morph: Vertex) -> VertexOutput {
...
var model = mesh[bevy_render::instance_index::get_instance_index(vertex_no_morph.instance_index)].model;
```
# Objective
shader defs associated with a shader via `load_internal_asset!` or
`Shader::from_xxx_with_defs` were being accidentally ignored for
top-level shaders.
## Solution
include the defs for top level shaders.
# Objective
This PR continues https://github.com/bevyengine/bevy/pull/8885
It aims to improve the `Mesh` documentation in the following ways:
- Put everything at the "top level" instead of the "impl".
- Explain better what is a Mesh, how it can be created, and that it can
be edited.
- Explain it can be used with a `Material`, and mention
`StandardMaterial`, `PbrBundle`, `ColorMaterial`, and
`ColorMesh2dBundle` since those cover most cases
- Mention the glTF/Bevy vocabulary discrepancy for "Mesh"
- Add an image for the example
- Various nitpicky modifications
## Note
- The image I added is 90.3ko which I think is small enough?
- Since rustdoc doesn't allow cross-reference not in dependencies of a
subcrate [yet](https://github.com/rust-lang/rust/issues/74481), I have a
lot of backtick references that are not links :(
- Since rustdoc doesn't allow linking to code in the crate (?) I put
link to github directly.
- Since rustdoc doesn't allow embed images in doc
[yet](https://github.com/rust-lang/rust/issues/32104), maybe
[soon](https://github.com/rust-lang/rfcs/pull/3397), I had to put only a
link to the image. I don't think it's worth adding
[embed_doc_image](https://docs.rs/embed-doc-image/latest/embed_doc_image/)
as a dependency for this.
# Objective
This PR updates the name of the enum variant used in the docs for
`OrthographicProjection`.
## Solution
- Change the outdated 'WindowScale` to `WindowSize`.
# Objective
- Reduce the number of rebindings to enable batching of draw commands
## Solution
- Use the new `GpuArrayBuffer` for `MeshUniform` data to store all
`MeshUniform` data in arrays within fewer bindings
- Sort opaque/alpha mask prepass, opaque/alpha mask main, and shadow
phases also by the batch per-object data binding dynamic offset to
improve performance on WebGL2.
---
## Changelog
- Changed: Per-object `MeshUniform` data is now managed by
`GpuArrayBuffer` as arrays in buffers that need to be indexed into.
## Migration Guide
Accessing the `model` member of an individual mesh object's shader
`Mesh` struct the old way where each `MeshUniform` was stored at its own
dynamic offset:
```rust
struct Vertex {
@location(0) position: vec3<f32>,
};
fn vertex(vertex: Vertex) -> VertexOutput {
var out: VertexOutput;
out.clip_position = mesh_position_local_to_clip(
mesh.model,
vec4<f32>(vertex.position, 1.0)
);
return out;
}
```
The new way where one needs to index into the array of `Mesh`es for the
batch:
```rust
struct Vertex {
@builtin(instance_index) instance_index: u32,
@location(0) position: vec3<f32>,
};
fn vertex(vertex: Vertex) -> VertexOutput {
var out: VertexOutput;
out.clip_position = mesh_position_local_to_clip(
mesh[vertex.instance_index].model,
vec4<f32>(vertex.position, 1.0)
);
return out;
}
```
Note that using the instance_index is the default way to pass the
per-object index into the shader, but if you wish to do custom rendering
approaches you can pass it in however you like.
---------
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com>
This is not used directly within the rendering code.
# Objective
- Remove extraneous dependency on `wgpu-hal` as it is not used.
## Solution
- The dependency has been removed and should have no externally visible
impact.
# Objective
The `QueryParIter::for_each_mut` function is required when doing
parallel iteration with mutable queries.
This results in an unfortunate stutter:
`query.par_iter_mut().par_for_each_mut()` ('mut' is repeated).
## Solution
- Make `for_each` compatible with mutable queries, and deprecate
`for_each_mut`. In order to prevent `for_each` from being called
multiple times in parallel, we take ownership of the QueryParIter.
---
## Changelog
- `QueryParIter::for_each` is now compatible with mutable queries.
`for_each_mut` has been deprecated as it is now redundant.
## Migration Guide
The method `QueryParIter::for_each_mut` has been deprecated and is no
longer functional. Use `for_each` instead, which now supports mutable
queries.
```rust
// Before:
query.par_iter_mut().for_each_mut(|x| ...);
// After:
query.par_iter_mut().for_each(|x| ...);
```
The method `QueryParIter::for_each` now takes ownership of the
`QueryParIter`, rather than taking a shared reference.
```rust
// Before:
let par_iter = my_query.par_iter().batching_strategy(my_batching_strategy);
par_iter.for_each(|x| {
// ...Do stuff with x...
par_iter.for_each(|y| {
// ...Do nested stuff with y...
});
});
// After:
my_query.par_iter().batching_strategy(my_batching_strategy).for_each(|x| {
// ...Do stuff with x...
my_query.par_iter().batching_strategy(my_batching_strategy).for_each(|y| {
// ...Do nested stuff with y...
});
});
```
# Objective
Fixes#9121
Context:
- `ImageTextureLoader` depends on `RenderDevice` to work out which
compressed image formats it can support
- `RenderDevice` is initialised by `RenderPlugin`
- https://github.com/bevyengine/bevy/pull/8336 made `RenderPlugin`
initialisation async
- This caused `RenderDevice` to be missing at the time of
`ImageTextureLoader` initialisation, which in turn meant UASTC encoded
ktx2 textures were being converted to unsupported formats, and thus
caused panics
## Solution
- Delay `ImageTextureLoader` initialisation
---
## Changelog
- Moved `ImageTextureLoader` initialisation from `ImagePlugin::build()`
to `ImagePlugin::finish()`
- Default to `CompressedImageFormats::NONE` if `RenderDevice` resource
is missing
---------
Co-authored-by: 66OJ66 <hi0obxud@anonaddy.me>
# Objective
Fix#8936.
## Solution
Stop using `unwrap` in the core pipelined rendering logic flow.
Separately also scoped the `sub app` span to just running the render app
instead of including the blocking send.
Current unknowns: should we use `std::panic::catch_unwind` around
running the render app? Other engine threads use it defensively, but
we're letting it bubble up here, and a user-created panic could cause a
deadlock if it kills the thread.
---
## Changelog
Fixed: Pipelined rendering should no longer have spurious panics upon
app exit.
# Objective
- Add a type for uploading a Rust `Vec<T>` to a GPU `array<T>`.
- Makes progress towards https://github.com/bevyengine/bevy/issues/89.
## Solution
- Port @superdump's `BatchedUniformBuffer` to bevy main, as a fallback
for WebGL2, which doesn't support storage buffers.
- Rather than getting an `array<T>` in a shader, you get an `array<T,
N>`, and have to rebind every N elements via dynamic offsets.
- Add `GpuArrayBuffer` to abstract over
`StorageBuffer<Vec<T>>`/`BatchedUniformBuffer`.
## Future Work
Add a shader macro kinda thing to abstract over the following
automatically:
https://github.com/bevyengine/bevy/pull/8204#pullrequestreview-1396911727
---
## Changelog
* Added `GpuArrayBuffer`, `GpuComponentArrayBufferPlugin`,
`GpuArrayBufferable`, and `GpuArrayBufferIndex` types.
* Added `DynamicUniformBuffer::new_with_alignment()`.
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Teodor Tanasoaia <28601907+teoxoy@users.noreply.github.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
Co-authored-by: Vincent <9408210+konsolas@users.noreply.github.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
# Objective
AssetPath shader imports check if the shader is added using the path
without quotes. this causes them to be re-added even if already present,
which can cause previous dependents to get unloaded leading to a
"missing import" error.
## Solution
fix the module name of AssetPath shaders used for checking if it's
already added to correctly use the quoted name.
# Objective
Continue #7867 now that we have URect #7984
- Return `URect` instead of `(UVec2, UVec2)` in
`Camera::physical_viewport_rect`
- Add `URect` and `IRect` to prelude
## Changelog
- Changed `Camera::physical_viewport_rect` return type from `(UVec2,
UVec2)` to `URect`
- `URect` and `IRect` were added to prelude
## Migration Guide
Before:
```rust
fn view_physical_camera_rect(camera_query: Query<&Camera>) {
let camera = camera_query.single();
let Some((min, max)) = camera.physical_viewport_rect() else { return };
dbg!(min, max);
}
```
After:
```rust
fn view_physical_camera_rect(camera_query: Query<&Camera>) {
let camera = camera_query.single();
let Some(URect { min, max }) = camera.physical_viewport_rect() else { return };
dbg!(min, max);
}
```
CI-capable version of #9086
---------
Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François <mockersf@gmail.com>
# Objective
Fix typos throughout the project.
## Solution
[`typos`](https://github.com/crate-ci/typos) project was used for
scanning, but no automatic corrections were applied. I checked
everything by hand before fixing.
Most of the changes are documentation/comments corrections. Also, there
are few trivial changes to code (variable name, pub(crate) function name
and a few error/panic messages).
## Unsolved
`bevy_reflect_derive` has
[typo](1b51053f19/crates/bevy_reflect/bevy_reflect_derive/src/type_path.rs (L76))
in enum variant name that I didn't fix. Enum is `pub(crate)`, so there
shouldn't be any trouble if fixed. However, code is tightly coupled with
macro usage, so I decided to leave it for more experienced contributor
just in case.
I created this manually as Github didn't want to run CI for the
workflow-generated PR. I'm guessing we didn't hit this in previous
releases because we used bors.
Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
# Objective
bevy_render currently has a dependency on a random older version of
once_cell which is not used anywhere.
## Solution
Remove the dependency
## Changelog
N/A
## Migration Guide
N/A
# 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>
Added `GizmoConfig::render_layers`, which will ensure Gizmos are only
rendered on cameras that can see those `RenderLayers`.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
operate on naga IR directly to improve handling of shader modules.
- give codespan reporting into imported modules
- allow glsl to be used from wgsl and vice-versa
the ultimate objective is to make it possible to
- provide user hooks for core shader functions (to modify light
behaviour within the standard pbr pipeline, for example)
- make automatic binding slot allocation possible
but ... since this is already big, adds some value and (i think) is at
feature parity with the existing code, i wanted to push this now.
## Solution
i made a crate called naga_oil (https://github.com/robtfm/naga_oil -
unpublished for now, could be part of bevy) which manages modules by
- building each module independantly to naga IR
- creating "header" files for each supported language, which are used to
build dependent modules/shaders
- make final shaders by combining the shader IR with the IR for imported
modules
then integrated this into bevy, replacing some of the existing shader
processing stuff. also reworked examples to reflect this.
## Migration Guide
shaders that don't use `#import` directives should work without changes.
the most notable user-facing difference is that imported
functions/variables/etc need to be qualified at point of use, and
there's no "leakage" of visible stuff into your shader scope from the
imports of your imports, so if you used things imported by your imports,
you now need to import them directly and qualify them.
the current strategy of including/'spreading' `mesh_vertex_output`
directly into a struct doesn't work any more, so these need to be
modified as per the examples (e.g. color_material.wgsl, or many others).
mesh data is assumed to be in bindgroup 2 by default, if mesh data is
bound into bindgroup 1 instead then the shader def `MESH_BINDGROUP_1`
needs to be added to the pipeline shader_defs.
# Objective
- Closes#7323
- Reduce texture blurriness for TAA
## Solution
- Add a `MipBias` component and view uniform.
- Switch material `textureSample()` calls to `textureSampleBias()`.
- Add a `-1.0` bias to TAA.
---
## Changelog
- Added `MipBias` camera component, mostly for internal use.
---------
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>