Migration Guides

Migration Guide: 0.11 to 0.12

Bevy relies heavily on improvements in the Rust language and compiler. As a result, the Minimum Supported Rust Version (MSRV) is "the latest stable release" of Rust.

API updates to the AnimationPlayer #

Animation

Some methods on AnimationPlayer have changed.

  • elapsed was removed. Use seek_time.
  • set_elapsed was removed. Use seek_to.
  • stop_repeating was removed. Use set_repeat(RepeatAnimation::Never).

If you were manually resetting animation state, you can use the new replay method instead.

Fix run-once runners #

App

app.ready() has been replaced by app.plugins_state() which will return more details on the current state of plugins in the app

Add support for KHR_materials_emissive_strength #

Assets

The GLTF asset loader will now factor in emissiveStrength when converting to Bevy’s StandardMaterial::emissive. Blender will export emissive materials using this field. Remove the field from your GLTF files or manually modify your materials post-asset-load to match how Bevy would load these files in previous versions.

Bevy Asset V2 #

Assets

Migrating a custom asset loader #

Existing asset loaders will need a few small changes to get them to work with Bevy Assets V2.

First, you’ll need to add the asset type as an associated type of the loader. This type is called Asset and represents the type of the “default asset” produced by the loader.

You’ll also need to add a Settings type which represents options that can be passed to the loader when you request an asset. If your asset has no settings, then you can just set it to the unit type.

pub struct MyAssetLoader;

impl AssetLoader for MyAssetLoader {
    type Asset = MyAsset;
    type Settings = ();

You’ll need to make a couple small changes to the load function as well. The load function now takes a settings parameter whose type is, you guessed it, Settings:

    fn load<'a>(
        &'a self,
        reader: &'a mut Reader,
        settings: &'a Self::Settings,
        load_context: &'a mut LoadContext,
    ) -> BoxedFuture<'a, Result<Self::Asset, anyhow::Error>> {

Again, if you are not using settings, then you can just ignore the parameter (prefix it with “_”).

Also, the second argument is now a reader rather than vector of bytes. If your existing code expects bytes, you can simply read the entire stream:

    fn load<'a>(
        &'a self,
        reader: &'a mut Reader,
        _settings: &'a Self::Settings,
        load_context: &'a mut LoadContext,
    ) -> BoxedFuture<'a, Result<Self::Asset, anyhow::Error>> {
        Box::pin(async move {
            let mut bytes = Vec::new();
            reader.read_to_end(&mut bytes).await?;

Finally, you’ll need to write the code which returns the default asset. This used to be done via a call to load_context.set_default_asset(), however in V2 you simply return the asset from the load function:

    fn load<'a>(
        &'a self,
        reader: &'a mut Reader,
        _settings: &'a Self::Settings,
        load_context: &'a mut LoadContext,
    ) -> BoxedFuture<'a, Result<Self::Asset, anyhow::Error>> {
        Box::pin(async move {
            let mut bytes = Vec::new();
            reader.read_to_end(&mut bytes).await?;
        let mut asset: MyAsset =
            serde_json::from_slice(&bytes).expect("unable to decode asset");
        Ok(asset)
    }

To use the new loader, make sure you register both the loader and the asset type:

app.register_asset_loader(MyAssetLoader)
    .init_asset::<MyAsset>()

Asset hot-reloading #

The feature filesystem_watcher has been renamed to file_watcher. In addition, you no longer need to manually configure the ChangeWatcher in the AssetPlugin as it is now configured automatically when the feature is enabled.

Labeled assets #

If your loader allows labeled assets, there are a couple of different ways to handle them. The simplest is to call load_context.labeled_asset_scope:

// Assume `asset.children` is a HashMap or something.
// Using `drain` here so that we take ownership and don't end up with
// multiple references to the same asset.
asset.children.drain().for_each(|(label, mut item)| {
    load_context.labeled_asset_scope(label, |lc| {
        // Do any additional processing on the item
        // Use 'lc' to load dependencies
        item
    });
});

You can use the provided load context (lc) to load additional assets. These will automatically be registered as dependencies of the labeled asset.

Using assets #

The actual call to load hasn’t changed:

let handle = server.load("path/to/my/asset.json");

// ...

let data = assets.get(&handle).unwrap();

Asset events #

There are a few changes to asset events. The event no longer contains a handle field, instead the event contains a field called id:

for ev in ev_template.read() {
    match ev {
        AssetEvent::Added { id } => {
            println!("Asset added");
        }
        AssetEvent::LoadedWithDependencies { id } => {
            println!("Asset loaded");
        }
        AssetEvent::Modified { id } => {
            println!("Asset modified");
        }
        AssetEvent::Removed { id } => {
            println!("Asset removed");
        }
    }
}

The id can be used to get access to the asset data, the asset’s path or load status. Asset handles also contain an id field which can be used to compare for equality:

AssetEvent::Modified { id } => {
    for cmp in query.iter() {
       if cmp.handle.id() == id {
           println!("Found it!");
       }
    }
}

Also, as you may have noticed, the set of events has changed. The most important of these is LoadedWithDependencies which tells you that the asset and all its dependencies have finished loading into memory.

UntypedHandle #

HandleUntyped has been renamed to UntypedHandle. HandleId has been replaced with UntypedAssetId and its typed equivalent AssetId<T>.

The new way to construct an untyped handle looks like this:

// 0.11
const MESH_HANDLE: HandleUntyped =
    HandleUntyped::weak_from_u64(Mesh::TYPE_UUID, 0x1f40128bac02a9b);
// 0.12
const MESH_HANDLE: UntypedHandle =
    UntypedHandle::Weak(UntypedAssetId::Uuid { type_id: TypeId::of::<Mesh>(), uuid: Uuid::from_u128(0x1f40128bac02a9b) });

Copy on Write AssetPaths #

Assets
// 0.11
AssetPath::new("logo.png", None);

// 0.12
AssetPath::from("logo.png");

// 0.11
AssetPath::new("scene.gltf", Some("Mesh0"));

// 0.12
AssetPath::from("scene.gltf").with_label("Mesh0");

AssetPath now serializes as AssetPath("some_path.extension#Label") instead of as AssetPath { path: "some_path.extension", label: Some("Label) }

Removed anyhow #

Assets
  • anyhow is no longer exported by bevy_asset; Add it to your own project (if required).
  • AssetLoader and AssetSaver have an associated type Error; Define an appropriate error type (e.g., using thiserror), or use a pre-made error type (e.g., anyhow::Error). Note that using anyhow::Error is a drop-in replacement.
  • AssetLoaderError has been removed; Define a new error type, or use an alternative (e.g., anyhow::Error)
  • All the first-party AssetLoaders and AssetSavers now return relevant (and narrow) error types instead of a single ambiguous type; Match over the specific error type, or encapsulate (Box<dyn>, thiserror, anyhow, etc.)

Non-blocking load_untyped using a wrapper asset #

Assets

Whenever possible use the typed API in order to directly get a handle to your asset. If you do not know the type or need to use load_untyped for a different reason, Bevy 0.12 introduces an additional layer of indirection. The asset server will return a handle to a LoadedUntypedAsset, which will load in the background. Once it is loaded, the untyped handle to the asset file can be retrieved from the LoadedUntypedAssets field handle.

reflect: TypePath part 2 #

Assets
Reflection
  • Rely on TypePath instead of std::any::type_name for all stability guarantees and for use in all reflection contexts, this is used through with one of the following APIs:
    • TypePath::type_path if you have a concrete type and not a value.
    • DynamicTypePath::reflect_type_path if you have an dyn Reflect value without a concrete type.
    • TypeInfo::type_path for use through the registry or if you want to work with the represented type of a DynamicFoo.
  • Remove type_name from manual Reflect implementations.
  • Use type_path and type_path_table in place of type_name on TypeInfo-like structs.
  • Use get_with_type_path(_mut) over get_with_type_name(_mut).

More ergonomic spatial audio #

Audio

Spatial audio now automatically uses the transform of the AudioBundle and of an entity with a SpatialListener component.

If you were manually scaling emitter/listener positions, you can use the spatial_scale field of AudioPlugin instead.

// 0.11
commands.spawn(
    SpatialAudioBundle {
        source: asset_server.load("sounds/Windless Slopes.ogg"),
        settings: PlaybackSettings::LOOP,
        spatial: SpatialSettings::new(listener_position, gap, emitter_position),
    },
);

fn update(
    emitter_query: Query<(&Transform, &SpatialAudioSink)>,
    listener_query: Query<&Transform, With<Listener>>,
) {
    let listener = listener_query.single();

    for (transform, sink) in &emitter_query {
        sink.set_emitter_position(transform.translation);
        sink.set_listener_position(*listener, gap);
    }
}

// 0.12
commands.spawn((
    SpatialBundle::from_transform(Transform::from_translation(emitter_position)),
    AudioBundle {
        source: asset_server.load("sounds/Windless Slopes.ogg"),
        settings: PlaybackSettings::LOOP.with_spatial(true),
    },
));

commands.spawn((
    SpatialBundle::from_transform(Transform::from_translation(listener_position)),
    SpatialListener::new(gap),
));

Simplify parallel iteration methods #

ECS

The method QueryParIter::for_each_mut has been deprecated and is no longer functional. Use for_each instead, which now supports mutable queries.

// 0.11
query.par_iter_mut().for_each_mut(|x| ...);

// 0.12
query.par_iter_mut().for_each(|x| ...);

The method QueryParIter::for_each now takes ownership of the QueryParIter, rather than taking a shared reference.

// 0.11
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...
    });
});

// 0.12
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...
    });
});

Fix safety invariants for WorldQuery::fetch and simplify cloning #

ECS

fetch invariants

The function WorldQuery::fetch has had the following safety invariant added:

If update_component_access includes any mutable accesses, then the caller must ensure that fetch is called no more than once for each entity/table_row in each archetype. If Self implements ReadOnlyWorldQuery, then this can safely be called multiple times.

This invariant was always required for soundness, but was previously undocumented. If you called this function manually anywhere, you should check to make sure that this invariant is not violated.

Removed clone_fetch

The function WorldQuery::clone_fetch has been removed. The associated type WorldQuery::Fetch now has the bound Clone.

// 0.11
struct MyFetch<'w> { ... }

unsafe impl WorldQuery for MyQuery {
    ...
    type Fetch<'w> = MyFetch<'w>
    unsafe fn clone_fetch<'w>(fetch: &Self::Fetch<'w>) -> Self::Fetch<'w> {
        MyFetch {
            field1: fetch.field1,
            field2: fetch.field2.clone(),
            ...
        }
    }
}

// 0.12
#[derive(Clone)]
struct MyFetch<'w> { ... }

unsafe impl WorldQuery for MyQuery {
    ...
    type Fetch<'w> = MyFetch<'w>;
}

Opt-out multi-threaded feature flag #

ECS

The multi-threaded feature in bevy_ecs and bevy_tasks is no longer enabled by default. However, this remains a default feature for the umbrella bevy crate.

if you are using bevy without default-features, or if you depend on bevy_ecs or bevy_tasks directly, you most likely want to enable this to allow systems to run in parallel.

ECS

ScheduleBuildError now has strings in more of its variants. You may need to adjust code that is handling these variants.

Add system.map(...) for transforming the output of a system #

ECS

The system_adapter functions have been deprecated: use .map instead, which is a lightweight alternative to .pipe.

// 0.11
my_system.pipe(system_adapter::ignore)
my_system.pipe(system_adapter::unwrap)
my_system.pipe(system_adapter::new(T::from))

// 0.12
my_system.map(std::mem::drop)
my_system.map(Result::unwrap)
my_system.map(T::from)

// 0.11
my_system.pipe(system_adapter::info)
my_system.pipe(system_adapter::dbg)
my_system.pipe(system_adapter::warn)
my_system.pipe(system_adapter::error)

// 0.12
my_system.map(bevy_utils::info)
my_system.map(bevy_utils::dbg)
my_system.map(bevy_utils::warn)
my_system.map(bevy_utils::error)

Replaced EntityMap with HashMap #

ECS
  • Calls to EntityMap::world_scope can be directly replaced with the following: map.world_scope(&mut world) -> world.world_scope(&mut map)
  • Calls to legacy EntityMap methods such as EntityMap::get must explicitly include de/reference symbols: let entity = map.get(parent); -> let &entity = map.get(&parent);

Rename ManualEventIterator #

ECS

The type ManualEventIterator has been renamed to EventIterator. Additionally, ManualEventIteratorWithId has been renamed to EventIteratorWithId.

Replaced EntityCommand Implementation for FnOnce #

ECS

1. New-Type FnOnce

Create an EntityCommand type which implements the method you previously wrote:

pub struct ClassicEntityCommand<F>(pub F);

impl<F> EntityCommand for ClassicEntityCommand<F>
where
    F: FnOnce(Entity, &mut World) + Send + 'static,
{
    fn apply(self, id: Entity, world: &mut World) {
        (self.0)(id, world);
    }
}

commands.add(ClassicEntityCommand(|id: Entity, world: &mut World| {
    /* ... */
}));

2. Extract (Entity, &mut World) from EntityMut

The method into_world_mut can be used to gain access to the World from an EntityMut.

let old = |id: Entity, world: &mut World| {
    /* ... */
};

let new = |mut entity: EntityWorldMut| {
    let id = entity.id();
    let world = entity.into_world_mut();
    /* ... */
};

Move schedule name into Schedule #

ECS

Schedule::new and App::add_schedule

// 0.11
let schedule = Schedule::new();
app.add_schedule(MyLabel, schedule);

// 0.12
let schedule = Schedule::new(MyLabel);
app.add_schedule(schedule);

if you aren’t inserting the schedule into the world and are using the schedule directly you can use the default constructor which reuses a default label.

// 0.11
let schedule = Schedule::new();
schedule.run(world);

// 0.12
let schedule = Schedule::default();
schedule.run(world);

Schedules::insert

// 0.11
let schedule = Schedule::new();
schedules.insert(MyLabel, schedule);

// 0.12
let schedule = Schedule::new(MyLabel);
schedules.insert(schedule);

World::add_schedule

// 0.11
let schedule = Schedule::new();
world.add_schedule(MyLabel, schedule);

// 0.12
let schedule = Schedule::new(MyLabel);
world.add_schedule(schedule);

Refactor EventReader::iter to read #

ECS
  • 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.

Replace IntoSystemSetConfig with IntoSystemSetConfigs #

ECS
  • Use App::configure_sets instead of App::configure_set
  • Use Schedule::configure_sets instead of Schedule::configure_set

Moved get_component(_unchecked_mut) from Query to QueryState #

ECS

use bevy_ecs::system::QueryComponentError; -> use bevy_ecs::query::QueryComponentError;

Fix naming on "tick" Column and ComponentSparseSet methods #

ECS

The following method names were renamed, from foo_ticks_bar to foo_tick_bar (ticks is now singular, tick):

  • ComponentSparseSet::get_added_ticksget_added_tick
  • ComponentSparseSet::get_changed_ticksget_changed_tick
  • Column::get_added_ticksget_added_tick
  • Column::get_changed_ticksget_changed_tick
  • Column::get_added_ticks_uncheckedget_added_tick_unchecked
  • Column::get_changed_ticks_uncheckedget_changed_tick_unchecked

Return a boolean from set_if_neq #

ECS

The trait method DetectChangesMut::set_if_neq now returns a boolean value indicating whether or not the value was changed. If you were implementing this function manually, you must now return true if the value was overwritten and false if the value was not.

Rename RemovedComponents::iter/iter_with_id to read/read_with_id #

ECS
fn react_on_removal(mut removed: RemovedComponents<MyComponent>) {
    // 0.11
    for entity in removed.iter() { /* ... */ }
    for (entity, id) in removed.iter_with_id() { /* ... */ }
    for entity in &mut removed { /* ... */ }

    // 0.12
    for entity in removed.read() { /* ... */ }
    for (entity, id) in removed.read_with_id() { /* ... */ }
    for entity in removed.read() { /* ... */ }
}

Remove States::variants and remove enum-only restriction its derive #

ECS

States::variants no longer exists. If you relied on this function, consider using a library that provides enum iterators.

Replace all labels with interned labels #

ECS
  • Replace BoxedScheduleLabel and Box<dyn ScheduleLabel> with InternedScheduleLabel or Interned<dyn ScheduleLabel>.

  • Replace BoxedSystemSet and Box<dyn SystemSet> with InternedSystemSet or Interned<dyn SystemSet>.

  • Replace AppLabelId with InternedAppLabel or Interned<dyn AppLabel>.

  • Types manually implementing ScheduleLabel, AppLabel or SystemSet need to implement:

    • dyn_hash directly instead of implementing DynHash
    • as_dyn_eq
  • Pass labels to World::try_schedule_scope, World::schedule_scope, World::try_run_schedule. World::run_schedule, Schedules::remove, Schedules::remove_entry, Schedules::contains, Schedules::get and Schedules::get_mut by value instead of by reference.

Add configure_schedules to App and Schedules to apply ScheduleBuildSettings to all schedules #

ECS
App
  • No breaking changes.
  • Adds Schedule::get_build_settings() getter for the schedule’s ScheduleBuildSettings.
  • Can replaced manual configuration of all schedules:
// 0.11
for (_, schedule) in app.world.resource_mut::<Schedules>().iter_mut() {
    schedule.set_build_settings(build_settings);
}

// 0.l2
app.configure_schedules(build_settings);

Only run event systems if they have tangible work to do #

ECS
App

Events<T>::update_system has been split off from the type and can be found at bevy_ecs::event::event_update_system.

Allow disjoint mutable world access via EntityMut #

ECS
Reflection

Removed the method EntityRef::world, to fix a soundness issue with queries. If you need access to &World while using an EntityRef, consider passing the world as a separate parameter.

EntityMut can no longer perform ‘structural’ world mutations, such as adding or removing components, or despawning the entity. Additionally, EntityMut::world, EntityMut::world_mut, EntityMut::into_world_mut, and EntityMut::world_scope have been removed. Instead, use the newly-added type EntityWorldMut, which is a helper type for working with &mut World.

Make builder types take and return Self #

ECS
Scenes

When using bevy_ecs::DynamicSceneBuilder and bevy_ecs::SceneBuilder, instead of binding the builder to a variable, directly use it. Methods on those types now consume Self, so you will need to re-bind the builder if you don’t build it immediately.

// 0.11
let mut scene_builder = DynamicSceneBuilder::from_world(&world);
let scene = scene_builder.extract_entity(a).extract_entity(b).build();

// 0.12
let scene = DynamicSceneBuilder::from_world(&world)
   .extract_entity(a)
   .extract_entity(b)
   .build();

Change AxisSettings livezone default #

Input

The default live zone bounds have been changed from -0.95..=0.95 to -1.0..=1.0 to align with more common usage. If you were relying on the old default, you can change this by modifying GamepadSettings::default_axis_settings.

Rename bevy_math::rects conversion methods #

Math

Replace Rect::as_urect with Rect::as_irect, Rect::as_rect with Rect::as_urect, and URect::as_urect with URect::as_irect.

Rename Bezier to CubicBezier for clarity #

Math

Change all Bezier references to CubicBezier

Add Cubic prefix to all cubic curve generators #

Math
  • Rename: BSpline -> CubicBSpline
  • Rename: CardinalSpline -> CubicCardinalSpline
  • Rename: Hermite -> CubicHermite

Remove the bevy_dylib feature #

Meta

If you were using Bevy’s bevy_dylib feature, use Bevy’s dynamic_linking feature instead.

# 0.11
cargo run --features bevy/bevy_dylib

# 0.12
cargo run --features bevy/dynamic_linking
[dependencies]
# 0.11
bevy = { version = "0.11", features = ["bevy_dylib"] }

# 0.12
bevy = { version = "0.12", features = ["dynamic_linking"] }

Refactor path module of bevy_reflect #

Reflection

If you were matching on the Err(ReflectPathError) value returned by GetPath and ParsedPath methods, now only the parse-related errors and the offset are publicly accessible. You can always use the fmt::Display to get a clear error message, but if you need programmatic access to the error types, please open an issue.

Make it so ParsedPath can be passed to GetPath #

Reflection

GetPath now requires Reflect. This reduces a lot of boilerplate on bevy’s side. If you were implementing manually GetPath on your own type, please get in touch!

ParsedPath::element[_mut] isn’t an inherent method of ParsedPath, you must now import ReflectPath. This is only relevant if you weren’t importing the bevy prelude.

-use bevy::reflect::ParsedPath;
+use bevy::reflect::{ParsedPath, ReflectPath};

parsed_path.element(reflect_type).unwrap()

Remove TypeRegistry re-export rename #

Reflection
  • TypeRegistry as re-exported by the wrapper bevy crate is now TypeRegistryArc
  • TypeRegistryInternal as re-exported by the wrapper bevy crate is now TypeRegistry

Provide getters for fields of ReflectFromPtr #

Reflection
  • ReflectFromPtr::as_reflect_ptr is now ReflectFromPtr::as_reflect
  • ReflectFromPtr::as_reflect_ptr_mut is now ReflectFromPtr::as_reflect_mut

bevy_reflect: Fix ignored/skipped field order #

Reflection
  • Fields marked #[reflect(skip_serializing)] now must implement Default or specify a custom default function with #[reflect(default = "path::to::some_func")]
#[derive(Reflect)]
struct MyStruct {
  #[reflect(skip_serializing)]
  #[reflect(default = "get_foo_default")]
  foo: Foo, // <- `Foo` does not impl `Default` so requires a custom function
  #[reflect(skip_serializing)]
  bar: Bar, // <- `Bar` impls `Default`
}

#[derive(Reflect)]
struct Foo(i32);

#[derive(Reflect, Default)]
struct Bar(i32);

fn get_foo_default() -> Foo {
  Foo(123)
}
  • SerializationData::new has been changed to expect an iterator of (usize, SkippedField) rather than one of just usize
// 0.11
SerializationData::new([0, 3].into_iter());

// 0.12
SerializationData::new([
  (0, SkippedField::new(field_0_default_fn)),
  (3, SkippedField::new(field_3_default_fn)),
].into_iter());
  • Serialization::is_ignored_field has been renamed to Serialization::is_field_skipped
  • Fields marked #[reflect(skip_serializing)] are now included in deserialization output. This may affect logic that expected those fields to be absent.

Return URect instead of (UVec2, UVec2) in Camera::physical_viewport_rect #

Rendering
// 0.11
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);
}

// 0.12
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);
}

Update bevy_window::PresentMode to mirror wgpu::PresentMode #

Rendering

Handle bevy_window::PresentMode::FifoRelaxed when tweaking window present mode manually.

Use GpuArrayBuffer for MeshUniform #

Rendering

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:

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 Meshes for the batch:

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.

Reduce the size of MeshUniform to improve performance #

Rendering

Sphere::intersects_obb and Frustum::intersects_obb now take an Affine3A instead of a Mat4. You can use Affine3A::from_mat4 or Transform::compute_affine to get an Affine3A.

MeshUniform now stores its current and previous model transforms as 4x3 matrices. Helper functions were added to bevy_pbr::mesh_functions to unpack the data.

// 0.11
var model = mesh[instance_index].model;

// 0.12
#import bevy_pbr::mesh_functions::affine_to_square

var model = affine_to_square(mesh[instance_index].model);

Reorder render sets, refactor bevy_sprite to take advantage #

Rendering
  • Assets such as materials and meshes should now be created in PrepareAssets e.g. prepare_assets<Mesh>
  • Queueing entities to RenderPhases 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

Split ComputedVisibility into two components to allow for accurate change detection and speed up visibility propagation #

Rendering

The ComputedVisibility component has been split into InheritedVisibility and ViewVisibility. Replace any usages of ComputedVisibility::is_visible_in_hierarchy with InheritedVisibility::get, and replace ComputedVisibility::is_visible_in_view with ViewVisibility::get.

// 0.11:
commands.spawn(VisibilityBundle {
    visibility: Visibility::Inherited,
    computed_visibility: ComputedVisibility::default(),
});

// 0.12:
commands.spawn(VisibilityBundle {
    visibility: Visibility::Inherited,
    inherited_visibility: InheritedVisibility::default(),
    view_visibility: ViewVisibility::default(),
});
// 0.11:
fn my_system(q: Query<&ComputedVisibility>) {
    for vis in &q {
        if vis.is_visible_in_hierarchy() {

// 0.12:
fn my_system(q: Query<&InheritedVisibility>) {
    for inherited_visibility in &q {
        if inherited_visibility.get() {
// 0.11:
fn my_system(q: Query<&ComputedVisibility>) {
    for vis in &q {
        if vis.is_visible_in_view() {

// 0.12:
fn my_system(q: Query<&ViewVisibility>) {
    for view_visibility in &q {
        if view_visibility.get() {
// 0.11:
fn my_system(mut q: Query<&mut ComputedVisibility>) {
    for vis in &mut q {
        vis.set_visible_in_view();

// 0.12:
fn my_system(mut q: Query<&mut ViewVisibility>) {
    for view_visibility in &mut q {
        view_visibility.set();

Cleanup visibility module #

Rendering

The check_visibility system’s Option<&NoFrustumCulling> parameter has been replaced by Has<NoFrustumCulling>, if you were calling it manually, you should change the type to match it

Allow other plugins to create renderer resources #

Rendering

The RenderPlugin now takes a RenderCreation enum instead of WgpuSettings. RenderSettings::default() returns RenderSettings::Automatic(WgpuSettings::default()). RenderSettings also implements From<WgpuSettings>.

// 0.11
RenderPlugin {
    wgpu_settings: WgpuSettings {
    ...
    },
}

// 0.12
RenderPlugin {
    render_creation: RenderCreation::Automatic(WgpuSettings {
    ...
    }),
}
// or
RenderPlugin {
    render_creation: WgpuSettings {
    ...
    }.into(),
}

Use EntityHashMap<Entity, T> for render world entity storage for better performance #

Rendering

Previously the render app extracted mesh entities and their component data from the main world and stored them as entities and components in the render world. Now they are extracted into essentially EntityHashMap<Entity, T> where T are structs containing an appropriate group of data. This means that while extract set systems will continue to run extract queries against the main world they will store their data in hash maps. Also, systems in later sets will either need to look up entities in the available resources such as RenderMeshInstances, or maintain their own EntityHashMap<Entity, T> for their own data.

// 0.11
fn queue_custom(
    material_meshes: Query<(Entity, &MeshTransforms, &Handle<Mesh>), With<InstanceMaterialData>>,
) {
    ...
    for (entity, mesh_transforms, mesh_handle) in &material_meshes {
        ...
    }
}

// 0.12
fn queue_custom(
    render_mesh_instances: Res<RenderMeshInstances>,
    instance_entities: Query<Entity, With<InstanceMaterialData>>,
) {
    ...
    for entity in &instance_entities {
        let Some(mesh_instance) = render_mesh_instances.get(&entity) else { continue; };
        // The mesh handle in `AssetId<Mesh>` form, and the `MeshTransforms` can now
        // be found in `mesh_instance` which is a `RenderMeshInstance`
        ...
    }
}

PCF For DirectionalLight/SpotLight Shadows #

Rendering

Shadows cast by directional lights or spotlights now have smoother edges. To revert to the old behavior, add ShadowFilteringMethod::Hardware2x2 to your cameras.

use Material for wireframes #

Rendering

WireframePipeline was removed. If you were using it directly, please create an issue explaining your use case.

Deferred Renderer #

Rendering

pbr shader cleanup #

Rendering

in custom material shaders:

  • pbr_functions::pbr no longer calls to pbr_functions::alpha_discard. if you were using the pbr function in a custom shader with alpha mask mode you now also need to call alpha_discard manually
  • rename imports of bevy_pbr::mesh_vertex_output to bevy_pbr::forward_io
  • rename instances of MeshVertexOutput to VertexOutput

in custom material prepass shaders:

  • rename instances of VertexOutput::clip_position to VertexOutput::position

*_PREPASS Shader Def Cleanup #

Rendering

When using functions from bevy_pbr::prepass_utils (prepass_depth(), prepass_normal(), prepass_motion_vector()) in contexts where these prepasses might be disabled, you should now wrap your calls with the appropriate #ifdef guards, (#ifdef DEPTH_PREPASS, #ifdef NORMAL_PREPASS, #ifdef MOTION_VECTOR_PREPASS) providing fallback logic where applicable.

Allow extensions to StandardMaterial #

Rendering

Manual implementations of AsBindGroup will need to be adjusted, the changes are pretty straightforward and can be seen in the diff for e.g. the texture_binding_array example.

Variable MeshPipeline View Bind Group Layout #

Rendering

MeshPipeline::view_layout and MeshPipeline::view_layout_multisampled have been replaced with a private array to accommodate for variable view bind group layouts. To obtain a view bind group layout for the current pipeline state, use the new MeshPipeline::get_view_layout() or MeshPipeline::get_view_layout_from_key() methods.

Update shader imports #

Rendering

naga_oil 0.10 reworks the import mechanism to support more syntax to make it more rusty, and test for item use before importing to determine which imports are modules and which are items, which allows:

  • use rust-style imports
#import bevy_pbr::{
    pbr_functions::{alpha_discard as discard, apply_pbr_lighting},
    mesh_bindings,
}
  • import partial paths:
#import part::of::path
// ...
path::remainder::function();

which will call to part::of::path::remainder::function

  • use fully qualified paths without importing:
// #import bevy_pbr::pbr_functions
bevy_pbr::pbr_functions::pbr()
  • use imported items without qualifying
#import bevy_pbr::pbr_functions::pbr
// for backwards compatibility the old style is still supported:
// #import bevy_pbr::pbr_functions pbr
// ...
pbr()
  • allows most imported items to end with _ and numbers (naga_oil#30). still doesn’t allow struct members to end with _ or numbers but it’s progress.
  • the vast majority of existing shader code will work without changes, but will emit “deprecated” warnings for old-style imports. these can be suppressed with the allow-deprecated feature.
  • partly breaks overrides (as far as i’m aware nobody uses these yet) - now overrides will only be applied if the overriding module is added as an additional import in the arguments to Composer::make_naga_module or Composer::add_composable_module. this is necessary to support determining whether imports are modules or items.

Bind group entries #

Rendering
  • Calls to RenderDevice::create_bind_group({BindGroupDescriptor { label, layout, entries }) must be amended to RenderDevice::create_bind_group(label, layout, entries).
  • If labels have been specified as "bind_group_name".into(), they need to change to just "bind_group_name". Some("bind_group_name") and None will still work, but Some("bind_group_name") can optionally be simplified to just "bind_group_name".

Detect cubemap for dds textures #

Rendering

If you are matching on a TextureError, you will need to add a new branch to handle TextureError::IncompleteCubemap.

Add convenient methods for Image #

Rendering

Replace calls to the Image::size() method with size_f32(). Replace calls to the Image::aspect_2d() method with aspect_ratio().

Use “specular occlusion” term to consistently extinguish fresnel on Ambient and Environment Map lights #

Rendering
  • If Fresnel highlights from Ambient and Environment Map lights are no longer visible in your materials, make sure you’re using a higher, physically plausible value of reflectance (⪆ 0.35).

Fix fog color being inaccurate #

Rendering

Colors in FogSettings struct (color and directional_light_color) are now sent to the GPU in linear space. If you were using Color::rgb()/Color::rgba() and would like to retain the previous colors, you can quickly fix it by switching to Color::rgb_linear()/Color::rgba_linear().

Image Sampler Improvements #

Rendering
  • When using the Image API, use ImageSamplerDescriptor instead of wgpu::SamplerDescriptor
  • If writing custom wgpu renderer features that work with Image, call &image_sampler.as_wgpu() to convert to a wgpu descriptor.

StandardMaterial Light Transmission #

Rendering
  • SsaoPipelineKey::temporal_noise has been renamed to SsaoPipelineKey::temporal_jitter
  • The TAA shader def (controlled by the presence of the TemporalAntiAliasSettings component in the camera) has been replaced with the TEMPORAL_JITTER shader def (controlled by the presence of the TemporalJitter component in the camera)
  • MeshPipelineKey::TAA has been replaced by MeshPipelineKey::TEMPORAL_JITTER
  • The TEMPORAL_NOISE shader def has been consolidated with TEMPORAL_JITTER

Increase default normal bias to avoid common artifacts #

Rendering

The default shadow_normal_bias value for DirectionalLight and SpotLight has changed to accommodate artifacts introduced with the new shadow PCF changes. It is unlikely (especially given the new PCF shadow behaviors with these values), but you might need to manually tweak this value if your scene requires a lower bias and it relied on the previous default value.

Make DirectionalLight Cascades computation generic over CameraProjection #

Rendering

If you have a component MyCustomProjection that implements CameraProjection:

  • You need to implement a new required associated method, get_frustum_corners, returning an array of the corners of a subset of the frustum with given z_near and z_far, in local camera space.
  • You can now add the build_directional_light_cascades::<MyCustomProjection> system in SimulationLightSystems::UpdateDirectionalLightCascades after clear_directional_light_cascades for your projection to work with directional lights.

Move skin code to a separate module #

Rendering
Animation

Renamed skinning systems, resources and components:

  • extract_skinned_meshes -> extract_skins
  • prepare_skinned_meshes -> prepare_skins
  • SkinnedMeshUniform -> SkinUniform
  • SkinnedMeshJoints -> SkinIndex

Move scene spawner systems to SpawnScene schedule #

Scenes

scene_spawner_system was moved to a new SpawnScene schedule which is run between Update and PostUpdate.

If you were ordering your own systems to run before scene_spawner_system in Update, that might no longer be necessary. If your system needs to run after scene_spawner_system, it should be moved to the SpawnScene or PostUpdate schedule.

Remove Resource and add Debug to TaskPoolOptions #

Tasks

If for some reason anyone is still using TaskPoolOptions as a Resource, they would now have to use a wrapper type:

#[derive(Resource)]
pub struct MyTaskPoolOptions(pub TaskPoolOptions);

Global TaskPool API improvements #

Tasks

Uses of ComputeTaskPool::init, AsyncComputeTaskPool::init and IoTaskPool::init should be changed to ::get_or_init.

Unify FixedTime and Time while fixing several problems #

Time
  • Change all Res<Time> instances that access raw_delta(), raw_elapsed() and related methods to Res<Time<Real>> and delta(), elapsed(), etc.
  • Change access to period from Res<FixedTime> to Res<Time<Fixed>> and use delta().
  • The default timestep has been changed from 60 Hz to 64 Hz. If you wish to restore the old behaviour, use app.insert_resource(Time::<Fixed>::from_hz(60.0)).
  • Change app.insert_resource(FixedTime::new(duration)) to app.insert_resource(Time::<Fixed>::from_duration(duration))
  • Change app.insert_resource(FixedTime::new_from_secs(secs)) to app.insert_resource(Time::<Fixed>::from_seconds(secs))
  • Change system.on_fixed_timer(duration) to system.on_timer(duration). Timers in systems placed in FixedUpdate schedule automatically use the fixed time clock.
  • Change ResMut<Time> calls to pause(), is_paused(), set_relative_speed() and related methods to ResMut<Time<Virtual>> calls. The API is the same, with the exception that relative_speed() will return the actual last ste relative speed, while effective_relative_speed() returns 0.0 if the time is paused and corresponds to the speed that was set when the update for the current frame started.

Change the default for the measure_func field of ContentSize to None. #

UI

The default for ContentSize now sets its measure_func to None, instead of a fixed size measure that returns Vec2::ZERO. The helper function fixed_size can be called with ContentSize::fixed_size(Vec2::ZERO) to get the previous behaviour.

Change UiScale to a tuple struct #

UI

Replace initialization of UiScale like UiScale { scale: 1.0 } with UiScale(1.0)

Cleanup some bevy_text pipeline.rs #

UI
  • The ResMut<TextPipeline> argument to measure_text_system doesn’t exist anymore. If you were calling this system manually, you should remove the argument.
  • The {min,max}_width_content_size fields of TextMeasureInfo are renamed to min and max respectively
  • Other changes to TextMeasureInfo may also break your code if you were manually building it. Please consider using the new TextMeasureInfo::from_text to build one instead.
  • TextPipeline::create_text_measure has been removed in favor of TextMeasureInfo::from_text

Make GridPlacement's fields non-zero and add accessor functions. #

UI

GridPlacement’s constructor functions no longer accept values of 0. Given any argument of 0 they will panic with a GridPlacementError.

Remove Val's try_* arithmetic methods #

UI

Val’s try_* arithmetic methods have been removed. To perform arithmetic on Vals deconstruct them using pattern matching.

Rename Val evaluate to resolve and implement viewport variant support #

UI
  • 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

TextLayoutInfo::size should hold the drawn size of the text, and not a scaled value. #

UI

The size value of TextLayoutInfo is stored in logical pixels and has been renamed to logical_size. There is no longer any need to divide by the window’s scale factor to get the logical size.

Have a separate implicit viewport node per root node + make viewport node Display::Grid #

UI
  • Bevy UI now lays out root nodes independently of each other in separate layout contexts. If you were relying on your root nodes being able to affect each other’s layouts, then you may need to wrap them in a single root node.
  • The implicit viewport node (which contains each user-specified root node) is now Display::Grid with align_items and justify_items both set to Start. You may need to add height: Val::Percent(100.) to your root nodes if you were previously relying on being implicitly set.

Rename num_font_atlases to len. #

UI

The num_font_atlases method of FontAtlasSet has been renamed to len.

Various accessibility API updates. #

UI

Change direct accesses of AccessibilityRequested to use AccessibilityRequested.::get()/AccessibilityRequested::set()

// 0.11
use std::sync::atomic::Ordering;

// To access
accessibility_requested.load(Ordering::SeqCst)
// To update
accessibility_requested.store(true, Ordering::SeqCst);

// 0.12
// To access
accessibility_requested.get()
// To update
accessibility_requested.set(true);

Add some more docs for bevy_text. #

UI

Usages of TextSettings.max_font_atlases from bevy_text must be changed to TextSettings.soft_max_font_atlases.

Update UI alignment docs #

UI

The JustifyContents enum has been expanded to include JustifyContents::Stretch.

Add option to toggle window control buttons #

Windowing

Added an enabled_buttons member to the Window struct through which users can enable or disable specific window control buttons.

Improve bevy_winit documentation #

Windowing
  • UpdateMode::Reactive { max_wait: .. } -> UpdateMode::Reactive { wait: .. }
  • UpdateMode::ReactiveLowPower { max_wait: .. } -> UpdateMode::ReactiveLowPower { wait: .. }

Work around naga/wgpu WGSL instance_index -> GLSL gl_InstanceID bug on WebGL2 #

Rendering

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 {
    // ...
    let instance_index = bevy_render::instance_index::get_instance_index(vertex_no_morph.instance_index);
    var model = mesh[instance_index].model;
}

Remove IntoIterator impl for &mut EventReader #

No area label

&mut EventReader does not implement IntoIterator anymore. replace for foo in &mut events by for foo in events.iter()

Update default `ClearColor`` to better match Bevy's branding #

Rendering

The default app background color has changed. To use the old default, add a ClearColor resource.

App::new()
    .insert_resource(ClearColor(Color::rgb(0.4, 0.4, 0.4)))
    .add_plugins(DefaultPlugins)

View Transformations #

mesh_functions::mesh_position_world_to_clip was moved and renamed to view_transformations::position_world_to_clip. It now also takes a vec3 instead of a vec4 so you will need to use vec4.xyz to get a vec3.

// 0.11
#import bevy_pbr::mesh_functions::mesh_position_world_to_clip
fn mesh_position_local_to_clip(model: mat4x4<f32>, vertex_position: vec4<f32>) -> vec4<f32> {
    let world_position = mesh_position_local_to_world(model, vertex_position);
    return mesh_position_world_to_clip(world_position);
}

// 0.12
#import bevy_pbr::view_transformations::position_world_to_clip;
fn mesh_position_local_to_clip(model: mat4x4<f32>, vertex_position: vec4<f32>) -> vec4<f32> {
    let world_position = mesh_position_local_to_world(model, vertex_position);
    return position_world_to_clip(world_position.xyz);
}