Add AssetChanged query filter

crates/bevy_asset/src/assets.rs

@@ -1,11 +1,12 @@
+use crate::asset_changed::AssetChanges;
 use crate::{
     self as bevy_asset, Asset, AssetEvent, AssetHandleProvider, AssetId, AssetServer, Handle,
     UntypedHandle,
 };
 use alloc::sync::Arc;
 use bevy_ecs::{
     prelude::EventWriter,
-    system::{Res, ResMut, Resource},
+    system::{Res, ResMut, Resource, SystemChangeTick},
 };
 use bevy_reflect::{Reflect, TypePath};
 use bevy_utils::HashMap;
@@ -559,7 +560,24 @@ impl<A: Asset> Assets<A> {
     /// A system that applies accumulated asset change events to the [`Events`] resource.
     ///
     /// [`Events`]: bevy_ecs::event::Events
-    pub fn asset_events(mut assets: ResMut<Self>, mut events: EventWriter<AssetEvent<A>>) {
+    pub(crate) fn asset_events(
+        mut assets: ResMut<Self>,
+        mut events: EventWriter<AssetEvent<A>>,
+        asset_changes: Option<ResMut<AssetChanges<A>>>,
+        ticks: SystemChangeTick,
+    ) {
+        use AssetEvent::{Added, LoadedWithDependencies, Modified, Removed};
+
+        if let Some(mut asset_changes) = asset_changes {
+            for new_event in &assets.queued_events {
+                match new_event {
+                    Removed { id } | AssetEvent::Unused { id } => asset_changes.remove(id),
+                    Added { id } | Modified { id } | LoadedWithDependencies { id } => {
+                        asset_changes.insert(*id, ticks.this_run());
+                    }
+                };
+            }
+        }
         events.send_batch(assets.queued_events.drain(..));
     }
 

crates/bevy_asset/src/lib.rs

@@ -141,13 +141,15 @@
 // FIXME(3492): remove once docs are ready
 // FIXME(15321): solve CI failures, then replace with `#![expect()]`.
 #![allow(missing_docs, reason = "Not all docs are written yet, see #3492.")]
+#![allow(unsafe_code)]
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
 #![doc(
     html_logo_url = "https://bevyengine.org/assets/icon.png",
     html_favicon_url = "https://bevyengine.org/assets/icon.png"
 )]
 
 extern crate alloc;
+extern crate core;
 
 pub mod io;
 pub mod meta;
@@ -159,13 +161,17 @@ pub mod transformer;
 ///
 /// This includes the most common types in this crate, re-exported for your convenience.
 pub mod prelude {
+    #[doc(hidden)]
+    pub use crate::asset_changed::AssetChanged;
+
     #[doc(hidden)]
     pub use crate::{
         Asset, AssetApp, AssetEvent, AssetId, AssetMode, AssetPlugin, AssetServer, Assets,
         DirectAssetAccessExt, Handle, UntypedHandle,
     };
 }
 
+mod asset_changed;
 mod assets;
 mod direct_access_ext;
 mod event;
@@ -205,6 +211,7 @@ use crate::{
 };
 use alloc::sync::Arc;
 use bevy_app::{App, Last, Plugin, PreUpdate};
+use bevy_ecs::prelude::Component;
 use bevy_ecs::{
     reflect::AppTypeRegistry,
     schedule::{IntoSystemConfigs, IntoSystemSetConfigs, SystemSet},
@@ -400,6 +407,15 @@ impl Plugin for AssetPlugin {
 )]
 pub trait Asset: VisitAssetDependencies + TypePath + Send + Sync + 'static {}
 
+/// A trait for newtypes that can be used as asset identifiers, i.e. handle wrappers.
+pub trait AsAssetId: Component {
+    /// The underlying asset type.
+    type Asset: Asset;
+
+    /// Converts this component to an asset id.
+    fn as_asset_id(&self) -> AssetId<Self::Asset>;
+}
+
 /// This trait defines how to visit the dependencies of an asset.
 /// For example, a 3D model might require both textures and meshes to be loaded.
 ///

crates/bevy_ecs/macros/src/world_query.rs

@@ -195,9 +195,10 @@ pub(crate) fn world_query_impl(
                 }
             }
 
-            fn get_state(components: &#path::component::Components) -> Option<#state_struct_name #user_ty_generics> {
+            fn get_state<'w>(world:  impl Into<#path::world::unsafe_world_cell::UnsafeWorldCell<'w>>) -> Option<#state_struct_name #user_ty_generics> {
+                let world = world.into();
                 Some(#state_struct_name {
-                    #(#named_field_idents: <#field_types>::get_state(components)?,)*
+                    #(#named_field_idents: <#field_types>::get_state(world)?,)*
                 })
             }
 

crates/bevy_ecs/src/query/fetch.rs

@@ -2,7 +2,7 @@ use crate::{
     archetype::{Archetype, Archetypes},
     bundle::Bundle,
     change_detection::{MaybeThinSlicePtrLocation, Ticks, TicksMut},
-    component::{Component, ComponentId, Components, Mutable, StorageType, Tick},
+    component::{Component, ComponentId, Mutable, StorageType, Tick},
     entity::{Entities, Entity, EntityLocation},
     query::{Access, DebugCheckedUnwrap, FilteredAccess, WorldQuery},
     storage::{ComponentSparseSet, Table, TableRow},
@@ -342,7 +342,7 @@ unsafe impl WorldQuery for Entity {
 
     fn init_state(_world: &mut World) {}
 
-    fn get_state(_components: &Components) -> Option<()> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<()> {
         Some(())
     }
 
@@ -418,7 +418,7 @@ unsafe impl WorldQuery for EntityLocation {
 
     fn init_state(_world: &mut World) {}
 
-    fn get_state(_components: &Components) -> Option<()> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<()> {
         Some(())
     }
 
@@ -501,7 +501,7 @@ unsafe impl<'a> WorldQuery for EntityRef<'a> {
 
     fn init_state(_world: &mut World) {}
 
-    fn get_state(_components: &Components) -> Option<()> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<()> {
         Some(())
     }
 
@@ -581,7 +581,7 @@ unsafe impl<'a> WorldQuery for EntityMut<'a> {
 
     fn init_state(_world: &mut World) {}
 
-    fn get_state(_components: &Components) -> Option<()> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<()> {
         Some(())
     }
 
@@ -673,7 +673,7 @@ unsafe impl<'a> WorldQuery for FilteredEntityRef<'a> {
         FilteredAccess::default()
     }
 
-    fn get_state(_components: &Components) -> Option<Self::State> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
         Some(FilteredAccess::default())
     }
 
@@ -767,7 +767,7 @@ unsafe impl<'a> WorldQuery for FilteredEntityMut<'a> {
         FilteredAccess::default()
     }
 
-    fn get_state(_components: &Components) -> Option<Self::State> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
         Some(FilteredAccess::default())
     }
 
@@ -853,12 +853,12 @@ where
     }
 
     fn init_state(world: &mut World) -> Self::State {
-        Self::get_state(world.components()).unwrap()
+        Self::get_state(world).unwrap()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
         let mut ids = SmallVec::new();
-        B::get_component_ids(components, &mut |maybe_id| {
+        B::get_component_ids(world.into().components(), &mut |maybe_id| {
             if let Some(id) = maybe_id {
                 ids.push(id);
             }
@@ -952,12 +952,12 @@ where
     }
 
     fn init_state(world: &mut World) -> Self::State {
-        Self::get_state(world.components()).unwrap()
+        Self::get_state(world).unwrap()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
         let mut ids = SmallVec::new();
-        B::get_component_ids(components, &mut |maybe_id| {
+        B::get_component_ids(world.into().components(), &mut |maybe_id| {
             if let Some(id) = maybe_id {
                 ids.push(id);
             }
@@ -1038,7 +1038,7 @@ unsafe impl WorldQuery for &Archetype {
 
     fn init_state(_world: &mut World) {}
 
-    fn get_state(_components: &Components) -> Option<()> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<()> {
         Some(())
     }
 
@@ -1197,8 +1197,8 @@ unsafe impl<T: Component> WorldQuery for &T {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -1396,8 +1396,8 @@ unsafe impl<'__w, T: Component> WorldQuery for Ref<'__w, T> {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -1595,8 +1595,8 @@ unsafe impl<'__w, T: Component> WorldQuery for &'__w mut T {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -1699,8 +1699,8 @@ unsafe impl<'__w, T: Component> WorldQuery for Mut<'__w, T> {
     }
 
     // Forwarded to `&mut T`
-    fn get_state(components: &Components) -> Option<ComponentId> {
-        <&mut T as WorldQuery>::get_state(components)
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<ComponentId> {
+        <&mut T as WorldQuery>::get_state(world)
     }
 
     // Forwarded to `&mut T`
@@ -1826,8 +1826,8 @@ unsafe impl<T: WorldQuery> WorldQuery for Option<T> {
         T::init_state(world)
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        T::get_state(components)
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        T::get_state(world)
     }
 
     fn matches_component_set(
@@ -1985,8 +1985,8 @@ unsafe impl<T: Component> WorldQuery for Has<T> {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -2144,8 +2144,9 @@ macro_rules! impl_anytuple_fetch {
                 ($($name::init_state(world),)*)
             }
             #[allow(unused_variables)]
-            fn get_state(components: &Components) -> Option<Self::State> {
-                Some(($($name::get_state(components)?,)*))
+            fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+                let world = world.into();
+                Some(($($name::get_state(world)?,)*))
             }
 
             fn matches_component_set(_state: &Self::State, _set_contains_id: &impl Fn(ComponentId) -> bool) -> bool {
@@ -2239,8 +2240,8 @@ unsafe impl<D: QueryData> WorldQuery for NopWorldQuery<D> {
         D::init_state(world)
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        D::get_state(components)
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        D::get_state(world)
     }
 
     fn matches_component_set(
@@ -2307,7 +2308,7 @@ unsafe impl<T: ?Sized> WorldQuery for PhantomData<T> {
 
     fn init_state(_world: &mut World) -> Self::State {}
 
-    fn get_state(_components: &Components) -> Option<Self::State> {
+    fn get_state<'w>(_world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
         Some(())
     }
 

crates/bevy_ecs/src/query/filter.rs

@@ -1,6 +1,6 @@
 use crate::{
     archetype::Archetype,
-    component::{Component, ComponentId, Components, StorageType, Tick},
+    component::{Component, ComponentId, StorageType, Tick},
     entity::Entity,
     query::{DebugCheckedUnwrap, FilteredAccess, StorageSwitch, WorldQuery},
     storage::{ComponentSparseSet, Table, TableRow},
@@ -194,8 +194,8 @@ unsafe impl<T: Component> WorldQuery for With<T> {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -305,8 +305,8 @@ unsafe impl<T: Component> WorldQuery for Without<T> {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<Self::State> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -488,8 +488,9 @@ macro_rules! impl_or_query_filter {
                 ($($filter::init_state(world),)*)
             }
 
-            fn get_state(components: &Components) -> Option<Self::State> {
-                Some(($($filter::get_state(components)?,)*))
+            fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<Self::State> {
+                let world = world.into();
+                Some(($($filter::get_state(world)?,)*))
             }
 
             fn matches_component_set(_state: &Self::State, _set_contains_id: &impl Fn(ComponentId) -> bool) -> bool {
@@ -763,8 +764,8 @@ unsafe impl<T: Component> WorldQuery for Added<T> {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<ComponentId> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<ComponentId> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(
@@ -996,8 +997,8 @@ unsafe impl<T: Component> WorldQuery for Changed<T> {
         world.register_component::<T>()
     }
 
-    fn get_state(components: &Components) -> Option<ComponentId> {
-        components.component_id::<T>()
+    fn get_state<'w>(world: impl Into<UnsafeWorldCell<'w>>) -> Option<ComponentId> {
+        world.into().components().component_id::<T>()
     }
 
     fn matches_component_set(