Merge branch 'bevyengine:main' into schema-types-metadata

Cargo.toml

@@ -3543,6 +3543,17 @@ description = "Illustrates how to use 9 Slicing for TextureAtlases in UI"
 category = "UI (User Interface)"
 wasm = true
 
+[[example]]
+name = "ui_transform"
+path = "examples/ui/ui_transform.rs"
+doc-scrape-examples = true
+
+[package.metadata.example.ui_transform]
+name = "UI Transform"
+description = "An example demonstrating how to translate, rotate and scale UI elements."
+category = "UI (User Interface)"
+wasm = true
+
 [[example]]
 name = "viewport_debug"
 path = "examples/ui/viewport_debug.rs"

crates/bevy_ecs/README.md

@@ -340,8 +340,8 @@ let mut world = World::new();
 let entity = world.spawn_empty().id();
 
 world.add_observer(|trigger: Trigger<Explode>, mut commands: Commands| {
-    println!("Entity {} goes BOOM!", trigger.target());
+    println!("Entity {} goes BOOM!", trigger.target().unwrap());
-    commands.entity(trigger.target()).despawn();
+    commands.entity(trigger.target().unwrap()).despawn();
 });
 
 world.flush();

crates/bevy_ecs/macros/src/lib.rs

@@ -1,4 +1,5 @@
-#![expect(missing_docs, reason = "Not all docs are written yet, see #3492.")]
+//! Macros for deriving ECS traits.
+
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
 
 extern crate proc_macro;
@@ -29,6 +30,7 @@ enum BundleFieldKind {
 const BUNDLE_ATTRIBUTE_NAME: &str = "bundle";
 const BUNDLE_ATTRIBUTE_IGNORE_NAME: &str = "ignore";
 
+/// Implement the `Bundle` trait.
 #[proc_macro_derive(Bundle, attributes(bundle))]
 pub fn derive_bundle(input: TokenStream) -> TokenStream {
     let ast = parse_macro_input!(input as DeriveInput);
@@ -187,6 +189,7 @@ pub fn derive_bundle(input: TokenStream) -> TokenStream {
     })
 }
 
+/// Implement the `MapEntities` trait.
 #[proc_macro_derive(MapEntities, attributes(entities))]
 pub fn derive_map_entities(input: TokenStream) -> TokenStream {
     let ast = parse_macro_input!(input as DeriveInput);
@@ -522,16 +525,19 @@ pub(crate) fn bevy_ecs_path() -> syn::Path {
     BevyManifest::shared().get_path("bevy_ecs")
 }
 
+/// Implement the `Event` trait.
 #[proc_macro_derive(Event, attributes(event))]
 pub fn derive_event(input: TokenStream) -> TokenStream {
     component::derive_event(input)
 }
 
+/// Implement the `Resource` trait.
 #[proc_macro_derive(Resource)]
 pub fn derive_resource(input: TokenStream) -> TokenStream {
     component::derive_resource(input)
 }
 
+/// Implement the `Component` trait.
 #[proc_macro_derive(
     Component,
     attributes(component, require, relationship, relationship_target, entities)
@@ -540,6 +546,7 @@ pub fn derive_component(input: TokenStream) -> TokenStream {
     component::derive_component(input)
 }
 
+/// Implement the `FromWorld` trait.
 #[proc_macro_derive(FromWorld, attributes(from_world))]
 pub fn derive_from_world(input: TokenStream) -> TokenStream {
     let bevy_ecs_path = bevy_ecs_path();

crates/bevy_ecs/src/bundle.rs

@@ -1143,7 +1143,7 @@ impl<'w> BundleInserter<'w> {
                 if archetype.has_replace_observer() {
                     deferred_world.trigger_observers(
                         ON_REPLACE,
-                        entity,
+                        Some(entity),
                         archetype_after_insert.iter_existing(),
                         caller,
                     );
@@ -1328,7 +1328,7 @@ impl<'w> BundleInserter<'w> {
             if new_archetype.has_add_observer() {
                 deferred_world.trigger_observers(
                     ON_ADD,
-                    entity,
+                    Some(entity),
                     archetype_after_insert.iter_added(),
                     caller,
                 );
@@ -1346,7 +1346,7 @@ impl<'w> BundleInserter<'w> {
                     if new_archetype.has_insert_observer() {
                         deferred_world.trigger_observers(
                             ON_INSERT,
-                            entity,
+                            Some(entity),
                             archetype_after_insert.iter_inserted(),
                             caller,
                         );
@@ -1365,7 +1365,7 @@ impl<'w> BundleInserter<'w> {
                     if new_archetype.has_insert_observer() {
                         deferred_world.trigger_observers(
                             ON_INSERT,
-                            entity,
+                            Some(entity),
                             archetype_after_insert.iter_added(),
                             caller,
                         );
@@ -1519,7 +1519,7 @@ impl<'w> BundleRemover<'w> {
             if self.old_archetype.as_ref().has_replace_observer() {
                 deferred_world.trigger_observers(
                     ON_REPLACE,
-                    entity,
+                    Some(entity),
                     bundle_components_in_archetype(),
                     caller,
                 );
@@ -1534,7 +1534,7 @@ impl<'w> BundleRemover<'w> {
             if self.old_archetype.as_ref().has_remove_observer() {
                 deferred_world.trigger_observers(
                     ON_REMOVE,
-                    entity,
+                    Some(entity),
                     bundle_components_in_archetype(),
                     caller,
                 );
@@ -1785,7 +1785,7 @@ impl<'w> BundleSpawner<'w> {
             if archetype.has_add_observer() {
                 deferred_world.trigger_observers(
                     ON_ADD,
-                    entity,
+                    Some(entity),
                     bundle_info.iter_contributed_components(),
                     caller,
                 );
@@ -1800,7 +1800,7 @@ impl<'w> BundleSpawner<'w> {
             if archetype.has_insert_observer() {
                 deferred_world.trigger_observers(
                     ON_INSERT,
-                    entity,
+                    Some(entity),
                     bundle_info.iter_contributed_components(),
                     caller,
                 );

crates/bevy_ecs/src/change_detection.rs

@@ -898,63 +898,39 @@ impl_debug!(Ref<'w, T>,);
 
 /// Unique mutable borrow of an entity's component or of a resource.
 ///
-/// This can be used in queries to opt into change detection on both their mutable and immutable forms, as opposed to
+/// This can be used in queries to access change detection from immutable query methods, as opposed
-/// `&mut T`, which only provides access to change detection while in its mutable form:
+/// to `&mut T` which only provides access to change detection from mutable query methods.
 ///
 /// ```rust
 /// # use bevy_ecs::prelude::*;
 /// # use bevy_ecs::query::QueryData;
 /// #
-/// #[derive(Component, Clone)]
+/// #[derive(Component, Clone, Debug)]
 /// struct Name(String);
 ///
-/// #[derive(Component, Clone, Copy)]
+/// #[derive(Component, Clone, Copy, Debug)]
 /// struct Health(f32);
 ///
-/// #[derive(Component, Clone, Copy)]
+/// fn my_system(mut query: Query<(Mut<Name>, &mut Health)>) {
-/// struct Position {
+///     // Mutable access provides change detection information for both parameters:
-///     x: f32,
+///     // - `name` has type `Mut<Name>`
-///     y: f32,
+///     // - `health` has type `Mut<Health>`
-/// };
+///     for (name, health) in query.iter_mut() {
-///
+///         println!("Name: {:?} (last changed {:?})", name, name.last_changed());
-/// #[derive(Component, Clone, Copy)]
+///         println!("Health: {:?} (last changed: {:?})", health, health.last_changed());
-/// struct Player {
+/// #        println!("{}{}", name.0, health.0); // Silence dead_code warning
-///     id: usize,
-/// };
-///
-/// #[derive(QueryData)]
-/// #[query_data(mutable)]
-/// struct PlayerQuery {
-///     id: &'static Player,
-///
-///     // Reacting to `PlayerName` changes is expensive, so we need to enable change detection when reading it.
-///     name: Mut<'static, Name>,
-///
-///     health: &'static mut Health,
-///     position: &'static mut Position,
 ///     }
 ///
-/// fn update_player_avatars(players_query: Query<PlayerQuery>) {
+///     // Immutable access only provides change detection for `Name`:
-///     // The item returned by the iterator is of type `PlayerQueryReadOnlyItem`.
+///     // - `name` has type `Ref<Name>`
-///     for player in players_query.iter() {
+///     // - `health` has type `&Health`
-///         if player.name.is_changed() {
+///     for (name, health) in query.iter() {
-///             // Update the player's name. This clones a String, and so is more expensive.
+///         println!("Name: {:?} (last changed {:?})", name, name.last_changed());
-///             update_player_name(player.id, player.name.clone());
+///         println!("Health: {:?}", health);
-///         }
-///
-///         // Update the health bar.
-///         update_player_health(player.id, *player.health);
-///
-///         // Update the player's position.
-///         update_player_position(player.id, *player.position);
 ///     }
 /// }
 ///
-/// # bevy_ecs::system::assert_is_system(update_player_avatars);
+/// # bevy_ecs::system::assert_is_system(my_system);
-///
-/// # fn update_player_name(player: &Player, new_name: Name) {}
-/// # fn update_player_health(player: &Player, new_health: Health) {}
-/// # fn update_player_position(player: &Player, new_position: Position) {}
 /// ```
 pub struct Mut<'w, T: ?Sized> {
     pub(crate) value: &'w mut T,

crates/bevy_ecs/src/observer/mod.rs

@@ -68,7 +68,7 @@ impl<'w, E, B: Bundle> Trigger<'w, E, B> {
     }
 
     /// Returns the [`Entity`] that was targeted by the `event` that triggered this observer. It may
-    /// be [`Entity::PLACEHOLDER`].
+    /// be [`None`] if the trigger is not for a particular entity.
     ///
     /// Observable events can target specific entities. When those events fire, they will trigger
     /// any observers on the targeted entities. In this case, the `target()` and `observer()` are
@@ -81,7 +81,7 @@ impl<'w, E, B: Bundle> Trigger<'w, E, B> {
     ///
     /// This is an important distinction: the entity reacting to an event is not always the same as
     /// the entity triggered by the event.
-    pub fn target(&self) -> Entity {
+    pub fn target(&self) -> Option<Entity> {
         self.trigger.target
     }
 
@@ -341,7 +341,7 @@ pub struct ObserverTrigger {
     /// The [`ComponentId`]s the trigger targeted.
     components: SmallVec<[ComponentId; 2]>,
     /// The entity the trigger targeted.
-    pub target: Entity,
+    pub target: Option<Entity>,
     /// The location of the source code that triggered the observer.
     pub caller: MaybeLocation,
 }
@@ -416,7 +416,7 @@ impl Observers {
     pub(crate) fn invoke<T>(
         mut world: DeferredWorld,
         event_type: ComponentId,
-        target: Entity,
+        target: Option<Entity>,
         components: impl Iterator<Item = ComponentId> + Clone,
         data: &mut T,
         propagate: &mut bool,
@@ -455,8 +455,8 @@ impl Observers {
         observers.map.iter().for_each(&mut trigger_observer);
 
         // Trigger entity observers listening for this kind of trigger
-        if target != Entity::PLACEHOLDER {
+        if let Some(target_entity) = target {
-            if let Some(map) = observers.entity_observers.get(&target) {
+            if let Some(map) = observers.entity_observers.get(&target_entity) {
                 map.iter().for_each(&mut trigger_observer);
             }
         }
@@ -469,8 +469,8 @@ impl Observers {
                     .iter()
                     .for_each(&mut trigger_observer);
 
-                if target != Entity::PLACEHOLDER {
+                if let Some(target_entity) = target {
-                    if let Some(map) = component_observers.entity_map.get(&target) {
+                    if let Some(map) = component_observers.entity_map.get(&target_entity) {
                         map.iter().for_each(&mut trigger_observer);
                     }
                 }
@@ -695,7 +695,7 @@ impl World {
             unsafe {
                 world.trigger_observers_with_data::<_, E::Traversal>(
                     event_id,
-                    Entity::PLACEHOLDER,
+                    None,
                     targets.components(),
                     event_data,
                     false,
@@ -708,7 +708,7 @@ impl World {
                 unsafe {
                     world.trigger_observers_with_data::<_, E::Traversal>(
                         event_id,
-                        target_entity,
+                        Some(target_entity),
                         targets.components(),
                         event_data,
                         E::AUTO_PROPAGATE,
@@ -999,20 +999,20 @@ mod tests {
         world.add_observer(
             |obs: Trigger<OnAdd, A>, mut res: ResMut<Order>, mut commands: Commands| {
                 res.observed("add_a");
-                commands.entity(obs.target()).insert(B);
+                commands.entity(obs.target().unwrap()).insert(B);
             },
         );
         world.add_observer(
             |obs: Trigger<OnRemove, A>, mut res: ResMut<Order>, mut commands: Commands| {
                 res.observed("remove_a");
-                commands.entity(obs.target()).remove::<B>();
+                commands.entity(obs.target().unwrap()).remove::<B>();
             },
         );
 
         world.add_observer(
             |obs: Trigger<OnAdd, B>, mut res: ResMut<Order>, mut commands: Commands| {
                 res.observed("add_b");
-                commands.entity(obs.target()).remove::<A>();
+                commands.entity(obs.target().unwrap()).remove::<A>();
             },
         );
         world.add_observer(|_: Trigger<OnRemove, B>, mut res: ResMut<Order>| {
@@ -1181,7 +1181,7 @@ mod tests {
         };
         world.spawn_empty().observe(system);
         world.add_observer(move |obs: Trigger<EventA>, mut res: ResMut<Order>| {
-            assert_eq!(obs.target(), Entity::PLACEHOLDER);
+            assert_eq!(obs.target(), None);
             res.observed("event_a");
         });
 
@@ -1208,7 +1208,7 @@ mod tests {
             .observe(|_: Trigger<EventA>, mut res: ResMut<Order>| res.observed("a_1"))
             .id();
         world.add_observer(move |obs: Trigger<EventA>, mut res: ResMut<Order>| {
-            assert_eq!(obs.target(), entity);
+            assert_eq!(obs.target().unwrap(), entity);
             res.observed("a_2");
         });
 
@@ -1628,7 +1628,7 @@ mod tests {
 
         world.add_observer(
             |trigger: Trigger<EventPropagating>, query: Query<&A>, mut res: ResMut<Order>| {
-                if query.get(trigger.target()).is_ok() {
+                if query.get(trigger.target().unwrap()).is_ok() {
                     res.observed("event");
                 }
             },
@@ -1651,7 +1651,7 @@ mod tests {
     fn observer_modifies_relationship() {
         fn on_add(trigger: Trigger<OnAdd, A>, mut commands: Commands) {
             commands
-                .entity(trigger.target())
+                .entity(trigger.target().unwrap())
                 .with_related_entities::<crate::hierarchy::ChildOf>(|rsc| {
                     rsc.spawn_empty();
                 });

crates/bevy_ecs/src/observer/runner.rs

@@ -123,8 +123,8 @@ pub type ObserverRunner = fn(DeferredWorld, ObserverTrigger, PtrMut, propagate:
 /// struct Explode;
 ///
 /// world.add_observer(|trigger: Trigger<Explode>, mut commands: Commands| {
-///     println!("Entity {} goes BOOM!", trigger.target());
+///     println!("Entity {} goes BOOM!", trigger.target().unwrap());
-///     commands.entity(trigger.target()).despawn();
+///     commands.entity(trigger.target().unwrap()).despawn();
 /// });
 ///
 /// world.flush();
@@ -157,7 +157,7 @@ pub type ObserverRunner = fn(DeferredWorld, ObserverTrigger, PtrMut, propagate:
 /// # struct Explode;
 /// world.entity_mut(e1).observe(|trigger: Trigger<Explode>, mut commands: Commands| {
 ///     println!("Boom!");
-///     commands.entity(trigger.target()).despawn();
+///     commands.entity(trigger.target().unwrap()).despawn();
 /// });
 ///
 /// world.entity_mut(e2).observe(|trigger: Trigger<Explode>, mut commands: Commands| {

crates/bevy_ecs/src/query/fetch.rs

@@ -47,6 +47,8 @@ use variadics_please::all_tuples;
 /// - **[`Ref`].**
 ///   Similar to change detection filters but it is used as a query fetch parameter.
 ///   It exposes methods to check for changes to the wrapped component.
+/// - **[`Mut`].**
+///   Mutable component access, with change detection data.
 /// - **[`Has`].**
 ///   Returns a bool indicating whether the entity has the specified component.
 ///

crates/bevy_ecs/src/relationship/related_methods.rs

@@ -1,6 +1,7 @@
 use crate::{
     bundle::Bundle,
     entity::{hash_set::EntityHashSet, Entity},
+    prelude::Children,
     relationship::{
         Relationship, RelationshipHookMode, RelationshipSourceCollection, RelationshipTarget,
     },
@@ -302,6 +303,15 @@ impl<'w> EntityWorldMut<'w> {
         self
     }
 
+    /// Despawns the children of this entity.
+    /// This entity will not be despawned.
+    ///
+    /// This is a specialization of [`despawn_related`](EntityWorldMut::despawn_related), a more general method for despawning via relationships.
+    pub fn despawn_children(&mut self) -> &mut Self {
+        self.despawn_related::<Children>();
+        self
+    }
+
     /// Inserts a component or bundle of components into the entity and all related entities,
     /// traversing the relationship tracked in `S` in a breadth-first manner.
     ///
@@ -467,6 +477,14 @@ impl<'a> EntityCommands<'a> {
         })
     }
 
+    /// Despawns the children of this entity.
+    /// This entity will not be despawned.
+    ///
+    /// This is a specialization of [`despawn_related`](EntityCommands::despawn_related), a more general method for despawning via relationships.
+    pub fn despawn_children(&mut self) -> &mut Self {
+        self.despawn_related::<Children>()
+    }
+
     /// Inserts a component or bundle of components into the entity and all related entities,
     /// traversing the relationship tracked in `S` in a breadth-first manner.
     ///

crates/bevy_ecs/src/schedule/executor/mod.rs

@@ -20,7 +20,7 @@ use crate::{
     prelude::{IntoSystemSet, SystemSet},
     query::{Access, FilteredAccessSet},
     schedule::{BoxedCondition, InternedSystemSet, NodeId, SystemTypeSet},
-    system::{ScheduleSystem, System, SystemIn, SystemParamValidationError},
+    system::{ScheduleSystem, System, SystemIn, SystemParamValidationError, SystemStateFlags},
     world::{unsafe_world_cell::UnsafeWorldCell, DeferredWorld, World},
 };
 
@@ -171,26 +171,9 @@ impl System for ApplyDeferred {
         const { &FilteredAccessSet::new() }
     }
 
-    fn is_send(&self) -> bool {
+    fn flags(&self) -> SystemStateFlags {
-        // Although this system itself does nothing on its own, the system
+        // non-send , exclusive , no deferred
-        // executor uses it to apply deferred commands. Commands must be allowed
+        SystemStateFlags::NON_SEND | SystemStateFlags::EXCLUSIVE
-        // to access non-send resources, so this system must be non-send for
-        // scheduling purposes.
-        false
-    }
-
-    fn is_exclusive(&self) -> bool {
-        // This system is labeled exclusive because it is used by the system
-        // executor to find places where deferred commands should be applied,
-        // and commands can only be applied with exclusive access to the world.
-        true
-    }
-
-    fn has_deferred(&self) -> bool {
-        // This system itself doesn't have any commands to apply, but when it
-        // is pulled from the schedule to be ran, the executor will apply
-        // deferred commands from other systems.
-        false
     }
 
     unsafe fn run_unsafe(

crates/bevy_ecs/src/schedule/mod.rs

@@ -874,7 +874,6 @@ mod tests {
         }
 
         #[test]
-        #[ignore = "Known failing but fix is non-trivial: https://github.com/bevyengine/bevy/issues/4381"]
         fn filtered_components() {
             let mut world = World::new();
             world.spawn(A);

crates/bevy_ecs/src/schedule/schedule.rs

@@ -1418,9 +1418,8 @@ impl ScheduleGraph {
             if system_a.is_exclusive() || system_b.is_exclusive() {
                 conflicting_systems.push((a, b, Vec::new()));
             } else {
-                let access_a = system_a.component_access();
+                let access_a = system_a.component_access_set();
-                let access_b = system_b.component_access();
+                let access_b = system_b.component_access_set();
-                if !access_a.is_compatible(access_b) {
                 match access_a.get_conflicts(access_b) {
                     AccessConflicts::Individual(conflicts) => {
                         let conflicts: Vec<_> = conflicts
@@ -1440,7 +1439,6 @@ impl ScheduleGraph {
                 }
             }
         }
-        }
 
         conflicting_systems
     }

crates/bevy_ecs/src/system/adapter_system.rs

@@ -137,16 +137,9 @@ where
         self.system.component_access_set()
     }
 
-    fn is_send(&self) -> bool {
+    #[inline]
-        self.system.is_send()
+    fn flags(&self) -> super::SystemStateFlags {
-    }
+        self.system.flags()
-
-    fn is_exclusive(&self) -> bool {
-        self.system.is_exclusive()
-    }
-
-    fn has_deferred(&self) -> bool {
-        self.system.has_deferred()
     }
 
     #[inline]

crates/bevy_ecs/src/system/combinator.rs

@@ -152,16 +152,9 @@ where
         &self.component_access_set
     }
 
-    fn is_send(&self) -> bool {
+    #[inline]
-        self.a.is_send() && self.b.is_send()
+    fn flags(&self) -> super::SystemStateFlags {
-    }
+        self.a.flags() | self.b.flags()
-
-    fn is_exclusive(&self) -> bool {
-        self.a.is_exclusive() || self.b.is_exclusive()
-    }
-
-    fn has_deferred(&self) -> bool {
-        self.a.has_deferred() || self.b.has_deferred()
     }
 
     unsafe fn run_unsafe(
@@ -378,16 +371,9 @@ where
         &self.component_access_set
     }
 
-    fn is_send(&self) -> bool {
+    #[inline]
-        self.a.is_send() && self.b.is_send()
+    fn flags(&self) -> super::SystemStateFlags {
-    }
+        self.a.flags() | self.b.flags()
-
-    fn is_exclusive(&self) -> bool {
-        self.a.is_exclusive() || self.b.is_exclusive()
-    }
-
-    fn has_deferred(&self) -> bool {
-        self.a.has_deferred() || self.b.has_deferred()
     }
 
     unsafe fn run_unsafe(

crates/bevy_ecs/src/system/exclusive_function_system.rs

@@ -13,7 +13,7 @@ use alloc::{borrow::Cow, vec, vec::Vec};
 use core::marker::PhantomData;
 use variadics_please::all_tuples;
 
-use super::SystemParamValidationError;
+use super::{SystemParamValidationError, SystemStateFlags};
 
 /// A function system that runs with exclusive [`World`] access.
 ///
@@ -98,22 +98,12 @@ where
     }
 
     #[inline]
-    fn is_send(&self) -> bool {
+    fn flags(&self) -> SystemStateFlags {
-        // exclusive systems should have access to non-send resources
+        // non-send , exclusive , no deferred
         // the executor runs exclusive systems on the main thread, so this
         // field reflects that constraint
-        false
-    }
-
-    #[inline]
-    fn is_exclusive(&self) -> bool {
-        true
-    }
-
-    #[inline]
-    fn has_deferred(&self) -> bool {
         // exclusive systems have no deferred system params
-        false
+        SystemStateFlags::NON_SEND | SystemStateFlags::EXCLUSIVE
     }
 
     #[inline]

crates/bevy_ecs/src/system/function_system.rs

@@ -17,7 +17,9 @@ use variadics_please::all_tuples;
 #[cfg(feature = "trace")]
 use tracing::{info_span, Span};
 
-use super::{IntoSystem, ReadOnlySystem, SystemParamBuilder, SystemParamValidationError};
+use super::{
+    IntoSystem, ReadOnlySystem, SystemParamBuilder, SystemParamValidationError, SystemStateFlags,
+};
 
 /// The metadata of a [`System`].
 #[derive(Clone)]
@@ -29,8 +31,7 @@ pub struct SystemMeta {
     pub(crate) component_access_set: FilteredAccessSet<ComponentId>,
     // NOTE: this must be kept private. making a SystemMeta non-send is irreversible to prevent
     // SystemParams from overriding each other
-    is_send: bool,
+    flags: SystemStateFlags,
-    has_deferred: bool,
     pub(crate) last_run: Tick,
     #[cfg(feature = "trace")]
     pub(crate) system_span: Span,
@@ -44,8 +45,7 @@ impl SystemMeta {
         Self {
             name: name.into(),
             component_access_set: FilteredAccessSet::default(),
-            is_send: true,
+            flags: SystemStateFlags::empty(),
-            has_deferred: false,
             last_run: Tick::new(0),
             #[cfg(feature = "trace")]
             system_span: info_span!("system", name = name),
@@ -78,7 +78,7 @@ impl SystemMeta {
     /// Returns true if the system is [`Send`].
     #[inline]
     pub fn is_send(&self) -> bool {
-        self.is_send
+        !self.flags.intersects(SystemStateFlags::NON_SEND)
     }
 
     /// Sets the system to be not [`Send`].
@@ -86,20 +86,20 @@ impl SystemMeta {
     /// This is irreversible.
     #[inline]
     pub fn set_non_send(&mut self) {
-        self.is_send = false;
+        self.flags |= SystemStateFlags::NON_SEND;
     }
 
     /// Returns true if the system has deferred [`SystemParam`]'s
     #[inline]
     pub fn has_deferred(&self) -> bool {
-        self.has_deferred
+        self.flags.intersects(SystemStateFlags::DEFERRED)
     }
 
     /// Marks the system as having deferred buffers like [`Commands`](`super::Commands`)
     /// This lets the scheduler insert [`ApplyDeferred`](`crate::prelude::ApplyDeferred`) systems automatically.
     #[inline]
     pub fn set_has_deferred(&mut self) {
-        self.has_deferred = true;
+        self.flags |= SystemStateFlags::DEFERRED;
     }
 
     /// Returns a reference to the [`FilteredAccessSet`] for [`ComponentId`].
@@ -631,18 +631,8 @@ where
     }
 
     #[inline]
-    fn is_send(&self) -> bool {
+    fn flags(&self) -> SystemStateFlags {
-        self.system_meta.is_send
+        self.system_meta.flags
-    }
-
-    #[inline]
-    fn is_exclusive(&self) -> bool {
-        false
-    }
-
-    #[inline]
-    fn has_deferred(&self) -> bool {
-        self.system_meta.has_deferred
     }
 
     #[inline]

crates/bevy_ecs/src/system/observer_system.rs

@@ -127,18 +127,8 @@ where
     }
 
     #[inline]
-    fn is_send(&self) -> bool {
+    fn flags(&self) -> super::SystemStateFlags {
-        self.observer.is_send()
+        self.observer.flags()
-    }
-
-    #[inline]
-    fn is_exclusive(&self) -> bool {
-        self.observer.is_exclusive()
-    }
-
-    #[inline]
-    fn has_deferred(&self) -> bool {
-        self.observer.has_deferred()
     }
 
     #[inline]

crates/bevy_ecs/src/system/query.rs

@@ -2016,17 +2016,67 @@ impl<'w, 's, D: QueryData, F: QueryFilter> Query<'w, 's, D, F> {
         self.as_nop().get(entity).is_ok()
     }
 
-    /// Returns a [`QueryLens`] that can be used to get a query with a more general fetch.
+    /// Returns a [`QueryLens`] that can be used to construct a new [`Query`] giving more
+    /// restrictive access to the entities matched by the current query.
     ///
-    /// For example, this can transform a `Query<(&A, &mut B)>` to a `Query<&B>`.
+    /// A transmute is valid only if `NewD` has a subset of the read, write, and required access
-    /// This can be useful for passing the query to another function. Note that since
+    /// of the current query. A precise description of the access required by each parameter
-    /// filter terms are dropped, non-archetypal filters like [`Added`](crate::query::Added),
+    /// type is given in the table below, but typical uses are to:
-    /// [`Changed`](crate::query::Changed) and [`Spawned`](crate::query::Spawned) will not be
+    /// * Remove components, e.g. `Query<(&A, &B)>` to `Query<&A>`.
-    /// respected. To maintain or change filter terms see [`Self::transmute_lens_filtered`]
+    /// * Retrieve an existing component with reduced or equal access, e.g. `Query<&mut A>` to `Query<&A>`
+    ///   or `Query<&T>` to `Query<Ref<T>>`.
+    /// * Add parameters with no new access, for example adding an `Entity` parameter.
+    ///
+    /// Note that since filter terms are dropped, non-archetypal filters like
+    /// [`Added`], [`Changed`] and [`Spawned`] will not be respected. To maintain or change filter
+    /// terms see [`Self::transmute_lens_filtered`].
+    ///
+    /// |`QueryData` parameter type|Access required|
+    /// |----|----|
+    /// |[`Entity`], [`EntityLocation`], [`SpawnDetails`], [`&Archetype`], [`Has<T>`], [`PhantomData<T>`]|No access|
+    /// |[`EntityMut`]|Read and write access to all components, but no required access|
+    /// |[`EntityRef`]|Read access to all components, but no required access|
+    /// |`&T`, [`Ref<T>`]|Read and required access to `T`|
+    /// |`&mut T`, [`Mut<T>`]|Read, write and required access to `T`|
+    /// |[`Option<T>`], [`AnyOf<(D, ...)>`]|Read and write access to `T`, but no required access|
+    /// |Tuples of query data and<br/>`#[derive(QueryData)]` structs|The union of the access of their subqueries|
+    /// |[`FilteredEntityRef`], [`FilteredEntityMut`]|Determined by the [`QueryBuilder`] used to construct them. Any query can be transmuted to them, and they will receive the access of the source query. When combined with other `QueryData`, they will receive any access of the source query that does not conflict with the other data|
+    ///
+    /// `transmute_lens` drops filter terms, but [`Self::transmute_lens_filtered`] supports returning a [`QueryLens`] with a new
+    /// filter type - the access required by filter parameters are as follows.
+    ///
+    /// |`QueryFilter` parameter type|Access required|
+    /// |----|----|
+    /// |[`Added<T>`], [`Changed<T>`]|Read and required access to `T`|
+    /// |[`With<T>`], [`Without<T>`]|No access|
+    /// |[`Or<(T, ...)>`]|Read access of the subqueries, but no required access|
+    /// |Tuples of query filters and `#[derive(QueryFilter)]` structs|The union of the access of their subqueries|
+    ///
+    /// [`Added`]: crate::query::Added
+    /// [`Added<T>`]: crate::query::Added
+    /// [`AnyOf<(D, ...)>`]: crate::query::AnyOf
+    /// [`&Archetype`]: crate::archetype::Archetype
+    /// [`Changed`]: crate::query::Changed
+    /// [`Changed<T>`]: crate::query::Changed
+    /// [`EntityMut`]: crate::world::EntityMut
+    /// [`EntityLocation`]: crate::entity::EntityLocation
+    /// [`EntityRef`]: crate::world::EntityRef
+    /// [`FilteredEntityRef`]: crate::world::FilteredEntityRef
+    /// [`FilteredEntityMut`]: crate::world::FilteredEntityMut
+    /// [`Has<T>`]: crate::query::Has
+    /// [`Mut<T>`]: crate::world::Mut
+    /// [`Or<(T, ...)>`]: crate::query::Or
+    /// [`QueryBuilder`]: crate::query::QueryBuilder
+    /// [`Ref<T>`]: crate::world::Ref
+    /// [`SpawnDetails`]: crate::query::SpawnDetails
+    /// [`Spawned`]: crate::query::Spawned
+    /// [`With<T>`]: crate::query::With
+    /// [`Without<T>`]: crate::query::Without
     ///
     /// ## Panics
     ///
-    /// This will panic if `NewD` is not a subset of the original fetch `D`
+    /// This will panic if the access required by `NewD` is not a subset of that required by
+    /// the original fetch `D`.
     ///
     /// ## Example
     ///
@@ -2065,30 +2115,6 @@ impl<'w, 's, D: QueryData, F: QueryFilter> Query<'w, 's, D, F> {
     /// # schedule.run(&mut world);
     /// ```
     ///
-    /// ## Allowed Transmutes
-    ///
-    /// Besides removing parameters from the query,
-    /// you can also make limited changes to the types of parameters.
-    /// The new query must have a subset of the *read*, *write*, and *required* access of the original query.
-    ///
-    /// * `&mut T` and [`Mut<T>`](crate::change_detection::Mut) have read, write, and required access to `T`
-    /// * `&T` and [`Ref<T>`](crate::change_detection::Ref) have read and required access to `T`
-    /// * [`Option<D>`] and [`AnyOf<(D, ...)>`](crate::query::AnyOf) have the read and write access of the subqueries, but no required access
-    /// * Tuples of query data and `#[derive(QueryData)]` structs have the union of the access of their subqueries
-    /// * [`EntityMut`](crate::world::EntityMut) has read and write access to all components, but no required access
-    /// * [`EntityRef`](crate::world::EntityRef) has read access to all components, but no required access
-    /// * [`Entity`], [`EntityLocation`], [`SpawnDetails`], [`&Archetype`], [`Has<T>`], and [`PhantomData<T>`] have no access at all,
-    ///   so can be added to any query
-    /// * [`FilteredEntityRef`](crate::world::FilteredEntityRef) and [`FilteredEntityMut`](crate::world::FilteredEntityMut)
-    ///   have access determined by the [`QueryBuilder`](crate::query::QueryBuilder) used to construct them.
-    ///   Any query can be transmuted to them, and they will receive the access of the source query.
-    ///   When combined with other `QueryData`, they will receive any access of the source query that does not conflict with the other data.
-    /// * [`Added<T>`](crate::query::Added) and [`Changed<T>`](crate::query::Changed) filters have read and required access to `T`
-    /// * [`With<T>`](crate::query::With) and [`Without<T>`](crate::query::Without) filters have no access at all,
-    ///   so can be added to any query
-    /// * Tuples of query filters and `#[derive(QueryFilter)]` structs have the union of the access of their subqueries
-    /// * [`Or<(F, ...)>`](crate::query::Or) filters have the read access of the subqueries, but no required access
-    ///
     /// ### Examples of valid transmutes
     ///
     /// ```rust
@@ -2165,28 +2191,21 @@ impl<'w, 's, D: QueryData, F: QueryFilter> Query<'w, 's, D, F> {
     /// // Nested inside of an `Or` filter, they have the same access as `Option<&T>`.
     /// assert_valid_transmute_filtered::<Option<&T>, (), Entity, Or<(Changed<T>, With<U>)>>();
     /// ```
-    ///
-    /// [`EntityLocation`]: crate::entity::EntityLocation
-    /// [`SpawnDetails`]: crate::query::SpawnDetails
-    /// [`&Archetype`]: crate::archetype::Archetype
-    /// [`Has<T>`]: crate::query::Has
     #[track_caller]
     pub fn transmute_lens<NewD: QueryData>(&mut self) -> QueryLens<'_, NewD> {
         self.transmute_lens_filtered::<NewD, ()>()
     }
 
-    /// Returns a [`QueryLens`] that can be used to get a query with a more general fetch.
+    /// Returns a [`QueryLens`] that can be used to construct a new `Query` giving more restrictive
+    /// access to the entities matched by the current query.
+    ///
     /// This consumes the [`Query`] to return results with the actual "inner" world lifetime.
     ///
-    /// For example, this can transform a `Query<(&A, &mut B)>` to a `Query<&B>`.
+    /// See [`Self::transmute_lens`] for a description of allowed transmutes.
-    /// This can be useful for passing the query to another function. Note that since
-    /// filter terms are dropped, non-archetypal filters like [`Added`](crate::query::Added),
-    /// [`Changed`](crate::query::Changed) and [`Spawned`](crate::query::Spawned) will not be
-    /// respected. To maintain or change filter terms see [`Self::transmute_lens_filtered`]
     ///
     /// ## Panics
     ///
-    /// This will panic if `NewD` is not a subset of the original fetch `Q`
+    /// This will panic if `NewD` is not a subset of the original fetch `D`
     ///
     /// ## Example
     ///
@@ -2225,22 +2244,6 @@ impl<'w, 's, D: QueryData, F: QueryFilter> Query<'w, 's, D, F> {
     /// # schedule.run(&mut world);
     /// ```
     ///
-    /// ## Allowed Transmutes
-    ///
-    /// Besides removing parameters from the query, you can also
-    /// make limited changes to the types of parameters.
-    ///
-    /// * Can always add/remove [`Entity`]
-    /// * Can always add/remove [`EntityLocation`]
-    /// * Can always add/remove [`&Archetype`]
-    /// * `Ref<T>` <-> `&T`
-    /// * `&mut T` -> `&T`
-    /// * `&mut T` -> `Ref<T>`
-    /// * [`EntityMut`](crate::world::EntityMut) -> [`EntityRef`](crate::world::EntityRef)
-    ///
-    /// [`EntityLocation`]: crate::entity::EntityLocation
-    /// [`&Archetype`]: crate::archetype::Archetype
-    ///
     /// # See also
     ///
     /// - [`transmute_lens`](Self::transmute_lens) to convert to a lens using a mutable borrow of the [`Query`].
@@ -2251,6 +2254,8 @@ impl<'w, 's, D: QueryData, F: QueryFilter> Query<'w, 's, D, F> {
 
     /// Equivalent to [`Self::transmute_lens`] but also includes a [`QueryFilter`] type.
     ///
+    /// See [`Self::transmute_lens`] for a description of allowed transmutes.
+    ///
     /// Note that the lens will iterate the same tables and archetypes as the original query. This means that
     /// additional archetypal query terms like [`With`](crate::query::With) and [`Without`](crate::query::Without)
     /// will not necessarily be respected and non-archetypal terms like [`Added`](crate::query::Added),
@@ -2266,10 +2271,13 @@ impl<'w, 's, D: QueryData, F: QueryFilter> Query<'w, 's, D, F> {
     /// Equivalent to [`Self::transmute_lens_inner`] but also includes a [`QueryFilter`] type.
     /// This consumes the [`Query`] to return results with the actual "inner" world lifetime.
     ///
+    /// See [`Self::transmute_lens`] for a description of allowed transmutes.
+    ///
     /// Note that the lens will iterate the same tables and archetypes as the original query. This means that
     /// additional archetypal query terms like [`With`](crate::query::With) and [`Without`](crate::query::Without)
     /// will not necessarily be respected and non-archetypal terms like [`Added`](crate::query::Added),
     /// [`Changed`](crate::query::Changed) and [`Spawned`](crate::query::Spawned) will only be respected if they
+    /// are in the type signature.
     ///
     /// # See also
     ///

crates/bevy_ecs/src/system/schedule_system.rs

@@ -8,7 +8,7 @@ use crate::{
     world::{unsafe_world_cell::UnsafeWorldCell, DeferredWorld, FromWorld, World},
 };
 
-use super::{IntoSystem, SystemParamValidationError};
+use super::{IntoSystem, SystemParamValidationError, SystemStateFlags};
 
 /// A wrapper system to change a system that returns `()` to return `Ok(())` to make it into a [`ScheduleSystem`]
 pub struct InfallibleSystemWrapper<S: System<In = ()>>(S);
@@ -44,18 +44,8 @@ impl<S: System<In = ()>> System for InfallibleSystemWrapper<S> {
     }
 
     #[inline]
-    fn is_send(&self) -> bool {
+    fn flags(&self) -> SystemStateFlags {
-        self.0.is_send()
+        self.0.flags()
-    }
-
-    #[inline]
-    fn is_exclusive(&self) -> bool {
-        self.0.is_exclusive()
-    }
-
-    #[inline]
-    fn has_deferred(&self) -> bool {
-        self.0.has_deferred()
     }
 
     #[inline]
@@ -172,16 +162,9 @@ where
         self.system.component_access_set()
     }
 
-    fn is_send(&self) -> bool {
+    #[inline]
-        self.system.is_send()
+    fn flags(&self) -> SystemStateFlags {
-    }
+        self.system.flags()
-
-    fn is_exclusive(&self) -> bool {
-        self.system.is_exclusive()
-    }
-
-    fn has_deferred(&self) -> bool {
-        self.system.has_deferred()
     }
 
     unsafe fn run_unsafe(
@@ -281,16 +264,9 @@ where
         self.system.component_access_set()
     }
 
-    fn is_send(&self) -> bool {
+    #[inline]
-        self.system.is_send()
+    fn flags(&self) -> SystemStateFlags {
-    }
+        self.system.flags()
-
-    fn is_exclusive(&self) -> bool {
-        self.system.is_exclusive()
-    }
-
-    fn has_deferred(&self) -> bool {
-        self.system.has_deferred()
     }
 
     unsafe fn run_unsafe(

crates/bevy_ecs/src/system/system.rs

@@ -2,6 +2,7 @@
     clippy::module_inception,
     reason = "This instance of module inception is being discussed; see #17353."
 )]
+use bitflags::bitflags;
 use core::fmt::Debug;
 use log::warn;
 use thiserror::Error;
@@ -19,6 +20,18 @@ use core::any::TypeId;
 
 use super::{IntoSystem, SystemParamValidationError};
 
+bitflags! {
+    /// Bitflags representing system states and requirements.
+    #[derive(Clone, Copy, PartialEq, Eq, Hash)]
+    pub struct SystemStateFlags: u8 {
+        /// Set if system cannot be sent across threads
+        const NON_SEND       = 1 << 0;
+        /// Set if system requires exclusive World access
+        const EXCLUSIVE      = 1 << 1;
+        /// Set if system has deferred buffers.
+        const DEFERRED       = 1 << 2;
+    }
+}
 /// An ECS system that can be added to a [`Schedule`](crate::schedule::Schedule)
 ///
 /// Systems are functions with all arguments implementing
@@ -50,14 +63,26 @@ pub trait System: Send + Sync + 'static {
     /// Returns the system's component [`FilteredAccessSet`].
     fn component_access_set(&self) -> &FilteredAccessSet<ComponentId>;
 
+    /// Returns the [`SystemStateFlags`] of the system.
+    fn flags(&self) -> SystemStateFlags;
+
     /// Returns true if the system is [`Send`].
-    fn is_send(&self) -> bool;
+    #[inline]
+    fn is_send(&self) -> bool {
+        !self.flags().intersects(SystemStateFlags::NON_SEND)
+    }
 
     /// Returns true if the system must be run exclusively.
-    fn is_exclusive(&self) -> bool;
+    #[inline]
+    fn is_exclusive(&self) -> bool {
+        self.flags().intersects(SystemStateFlags::EXCLUSIVE)
+    }
 
     /// Returns true if system has deferred buffers.
-    fn has_deferred(&self) -> bool;
+    #[inline]
+    fn has_deferred(&self) -> bool {
+        self.flags().intersects(SystemStateFlags::DEFERRED)
+    }
 
     /// Runs the system with the given input in the world. Unlike [`System::run`], this function
     /// can be called in parallel with other systems and may break Rust's aliasing rules

crates/bevy_ecs/src/world/deferred_world.rs

@@ -23,7 +23,7 @@ use super::{unsafe_world_cell::UnsafeWorldCell, Mut, World, ON_INSERT, ON_REPLAC
 ///
 /// This means that in order to add entities, for example, you will need to use commands instead of the world directly.
 pub struct DeferredWorld<'w> {
-    // SAFETY: Implementors must not use this reference to make structural changes
+    // SAFETY: Implementers must not use this reference to make structural changes
     world: UnsafeWorldCell<'w>,
 }
 
@@ -157,7 +157,7 @@ impl<'w> DeferredWorld<'w> {
             if archetype.has_replace_observer() {
                 self.trigger_observers(
                     ON_REPLACE,
-                    entity,
+                    Some(entity),
                     [component_id].into_iter(),
                     MaybeLocation::caller(),
                 );
@@ -197,7 +197,7 @@ impl<'w> DeferredWorld<'w> {
             if archetype.has_insert_observer() {
                 self.trigger_observers(
                     ON_INSERT,
-                    entity,
+                    Some(entity),
                     [component_id].into_iter(),
                     MaybeLocation::caller(),
                 );
@@ -738,7 +738,7 @@ impl<'w> DeferredWorld<'w> {
     pub(crate) unsafe fn trigger_observers(
         &mut self,
         event: ComponentId,
-        target: Entity,
+        target: Option<Entity>,
         components: impl Iterator<Item = ComponentId> + Clone,
         caller: MaybeLocation,
     ) {
@@ -761,7 +761,7 @@ impl<'w> DeferredWorld<'w> {
     pub(crate) unsafe fn trigger_observers_with_data<E, T>(
         &mut self,
         event: ComponentId,
-        mut target: Entity,
+        target: Option<Entity>,
         components: impl Iterator<Item = ComponentId> + Clone,
         data: &mut E,
         mut propagate: bool,
@@ -769,7 +769,6 @@ impl<'w> DeferredWorld<'w> {
     ) where
         T: Traversal<E>,
     {
-        loop {
         Observers::invoke::<_>(
             self.reborrow(),
             event,
@@ -779,8 +778,11 @@ impl<'w> DeferredWorld<'w> {
             &mut propagate,
             caller,
         );
+        let Some(mut target) = target else { return };
+
+        loop {
             if !propagate {
-                break;
+                return;
             }
             if let Some(traverse_to) = self
                 .get_entity(target)
@@ -792,6 +794,15 @@ impl<'w> DeferredWorld<'w> {
             } else {
                 break;
             }
+            Observers::invoke::<_>(
+                self.reborrow(),
+                event,
+                Some(target),
+                components.clone(),
+                data,
+                &mut propagate,
+                caller,
+            );
         }
     }
 

crates/bevy_ecs/src/world/entity_ref.rs

@@ -2371,7 +2371,7 @@ impl<'w> EntityWorldMut<'w> {
             if archetype.has_despawn_observer() {
                 deferred_world.trigger_observers(
                     ON_DESPAWN,
-                    self.entity,
+                    Some(self.entity),
                     archetype.components(),
                     caller,
                 );
@@ -2385,7 +2385,7 @@ impl<'w> EntityWorldMut<'w> {
             if archetype.has_replace_observer() {
                 deferred_world.trigger_observers(
                     ON_REPLACE,
-                    self.entity,
+                    Some(self.entity),
                     archetype.components(),
                     caller,
                 );
@@ -2400,7 +2400,7 @@ impl<'w> EntityWorldMut<'w> {
             if archetype.has_remove_observer() {
                 deferred_world.trigger_observers(
                     ON_REMOVE,
-                    self.entity,
+                    Some(self.entity),
                     archetype.components(),
                     caller,
                 );
@@ -5749,7 +5749,9 @@ mod tests {
         let entity = world
             .spawn_empty()
             .observe(|trigger: Trigger<TestEvent>, mut commands: Commands| {
-                commands.entity(trigger.target()).insert(TestComponent(0));
+                commands
+                    .entity(trigger.target().unwrap())
+                    .insert(TestComponent(0));
             })
             .id();
 
@@ -5769,7 +5771,7 @@ mod tests {
         let mut world = World::new();
         world.add_observer(
             |trigger: Trigger<OnAdd, TestComponent>, mut commands: Commands| {
-                commands.entity(trigger.target()).despawn();
+                commands.entity(trigger.target().unwrap()).despawn();
             },
         );
         let entity = world.spawn_empty().id();

crates/bevy_image/src/image_loader.rs

@@ -81,19 +81,35 @@ impl ImageLoader {
     }
 }
 
+/// How to determine an image's format when loading.
 #[derive(Serialize, Deserialize, Default, Debug, Clone)]
 pub enum ImageFormatSetting {
+    /// Determine the image format from its file extension.
+    ///
+    /// This is the default.
     #[default]
     FromExtension,
+    /// Declare the image format explicitly.
     Format(ImageFormat),
+    /// Guess the image format by looking for magic bytes at the
+    /// beginning of its data.
     Guess,
 }
 
+/// Settings for loading an [`Image`] using an [`ImageLoader`].
 #[derive(Serialize, Deserialize, Debug, Clone)]
 pub struct ImageLoaderSettings {
+    /// How to determine the image's format.
     pub format: ImageFormatSetting,
+    /// Specifies whether image data is linear
+    /// or in sRGB space when this is not determined by
+    /// the image format.
     pub is_srgb: bool,
+    /// [`ImageSampler`] to use when rendering - this does
+    /// not affect the loading of the image data.
     pub sampler: ImageSampler,
+    /// Where the asset will be used - see the docs on
+    /// [`RenderAssetUsages`] for details.
     pub asset_usage: RenderAssetUsages,
 }
 
@@ -108,11 +124,14 @@ impl Default for ImageLoaderSettings {
     }
 }
 
+/// An error when loading an image using [`ImageLoader`].
 #[non_exhaustive]
 #[derive(Debug, Error)]
 pub enum ImageLoaderError {
-    #[error("Could load shader: {0}")]
+    /// An error occurred while trying to load the image bytes.
+    #[error("Failed to load image bytes: {0}")]
     Io(#[from] std::io::Error),
+    /// An error occurred while trying to decode the image bytes.
     #[error("Could not load texture file: {0}")]
     FileTexture(#[from] FileTextureError),
 }
@@ -170,7 +189,7 @@ impl AssetLoader for ImageLoader {
 
 /// An error that occurs when loading a texture from a file.
 #[derive(Error, Debug)]
-#[error("Error reading image file {path}: {error}, this is an error in `bevy_render`.")]
+#[error("Error reading image file {path}: {error}.")]
 pub struct FileTextureError {
     error: TextureError,
     path: String,

crates/bevy_input_focus/src/lib.rs

@@ -394,7 +394,7 @@ mod tests {
         trigger: Trigger<FocusedInput<KeyboardInput>>,
         mut query: Query<&mut GatherKeyboardEvents>,
     ) {
-        if let Ok(mut gather) = query.get_mut(trigger.target()) {
+        if let Ok(mut gather) = query.get_mut(trigger.target().unwrap()) {
             if let Key::Character(c) = &trigger.input.logical_key {
                 gather.0.push_str(c.as_str());
             }

crates/bevy_pbr/src/render/light.rs

@@ -551,7 +551,7 @@ pub(crate) fn add_light_view_entities(
     trigger: Trigger<OnAdd, (ExtractedDirectionalLight, ExtractedPointLight)>,
     mut commands: Commands,
 ) {
-    if let Ok(mut v) = commands.get_entity(trigger.target()) {
+    if let Ok(mut v) = commands.get_entity(trigger.target().unwrap()) {
         v.insert(LightViewEntities::default());
     }
 }
@@ -561,7 +561,7 @@ pub(crate) fn extracted_light_removed(
     trigger: Trigger<OnRemove, (ExtractedDirectionalLight, ExtractedPointLight)>,
     mut commands: Commands,
 ) {
-    if let Ok(mut v) = commands.get_entity(trigger.target()) {
+    if let Ok(mut v) = commands.get_entity(trigger.target().unwrap()) {
         v.try_remove::<LightViewEntities>();
     }
 }
@@ -571,7 +571,7 @@ pub(crate) fn remove_light_view_entities(
     query: Query<&LightViewEntities>,
     mut commands: Commands,
 ) {
-    if let Ok(entities) = query.get(trigger.target()) {
+    if let Ok(entities) = query.get(trigger.target().unwrap()) {
         for v in entities.0.values() {
             for e in v.iter().copied() {
                 if let Ok(mut v) = commands.get_entity(e) {

crates/bevy_picking/src/hover.rs

@@ -208,18 +208,6 @@ pub fn update_interactions(
     mut pointers: Query<(&PointerId, &PointerPress, &mut PointerInteraction)>,
     mut interact: Query<&mut PickingInteraction>,
 ) {
-    // Clear all previous hover data from pointers and entities
-    for (pointer, _, mut pointer_interaction) in &mut pointers {
-        pointer_interaction.sorted_entities.clear();
-        if let Some(previously_hovered_entities) = previous_hover_map.get(pointer) {
-            for entity in previously_hovered_entities.keys() {
-                if let Ok(mut interaction) = interact.get_mut(*entity) {
-                    *interaction = PickingInteraction::None;
-                }
-            }
-        }
-    }
-
     // Create a map to hold the aggregated interaction for each entity. This is needed because we
     // need to be able to insert the interaction component on entities if they do not exist. To do
     // so we need to know the final aggregated interaction state to avoid the scenario where we set
@@ -239,13 +227,29 @@ pub fn update_interactions(
     }
 
     // Take the aggregated entity states and update or insert the component if missing.
-    for (hovered_entity, new_interaction) in new_interaction_state.drain() {
+    for (&hovered_entity, &new_interaction) in new_interaction_state.iter() {
         if let Ok(mut interaction) = interact.get_mut(hovered_entity) {
-            *interaction = new_interaction;
+            interaction.set_if_neq(new_interaction);
         } else if let Ok(mut entity_commands) = commands.get_entity(hovered_entity) {
             entity_commands.try_insert(new_interaction);
         }
     }
+
+    // Clear all previous hover data from pointers that are no longer hovering any entities.
+    // We do this last to preserve change detection for picking interactions.
+    for (pointer, _, _) in &mut pointers {
+        let Some(previously_hovered_entities) = previous_hover_map.get(pointer) else {
+            continue;
+        };
+
+        for entity in previously_hovered_entities.keys() {
+            if !new_interaction_state.contains_key(entity) {
+                if let Ok(mut interaction) = interact.get_mut(*entity) {
+                    interaction.set_if_neq(PickingInteraction::None);
+                }
+            }
+        }
+    }
 }
 
 /// Merge the interaction state of this entity into the aggregated map.

crates/bevy_picking/src/lib.rs

@@ -55,13 +55,13 @@
 //!         // Spawn your entity here, e.g. a Mesh.
 //!         // When dragged, mutate the `Transform` component on the dragged target entity:
 //!         .observe(|trigger: Trigger<Pointer<Drag>>, mut transforms: Query<&mut Transform>| {
-//!             let mut transform = transforms.get_mut(trigger.target()).unwrap();
+//!             let mut transform = transforms.get_mut(trigger.target().unwrap()).unwrap();
 //!             let drag = trigger.event();
 //!             transform.rotate_local_y(drag.delta.x / 50.0);
 //!         })
 //!         .observe(|trigger: Trigger<Pointer<Click>>, mut commands: Commands| {
-//!             println!("Entity {} goes BOOM!", trigger.target());
+//!             println!("Entity {} goes BOOM!", trigger.target().unwrap());
-//!             commands.entity(trigger.target()).despawn();
+//!             commands.entity(trigger.target().unwrap()).despawn();
 //!         })
 //!         .observe(|trigger: Trigger<Pointer<Over>>, mut events: EventWriter<Greeting>| {
 //!             events.write(Greeting);

crates/bevy_render/Cargo.toml

@@ -119,7 +119,7 @@ wesl = { version = "0.1.2", optional = true }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 # Omit the `glsl` feature in non-WebAssembly by default.
-naga_oil = { version = "0.17", default-features = false, features = [
+naga_oil = { version = "0.17.1", default-features = false, features = [
   "test_shader",
 ] }
 
@@ -127,7 +127,7 @@ naga_oil = { version = "0.17", default-features = false, features = [
 proptest = "1"
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
-naga_oil = "0.17"
+naga_oil = "0.17.1"
 js-sys = "0.3"
 web-sys = { version = "0.3.67", features = [
   'Blob',

crates/bevy_render/src/camera/camera.rs

@@ -1060,6 +1060,7 @@ pub fn camera_system(
 #[reflect(opaque)]
 #[reflect(Component, Default, Clone)]
 pub struct CameraMainTextureUsages(pub TextureUsages);
+
 impl Default for CameraMainTextureUsages {
     fn default() -> Self {
         Self(
@@ -1070,6 +1071,13 @@ impl Default for CameraMainTextureUsages {
     }
 }
 
+impl CameraMainTextureUsages {
+    pub fn with(mut self, usages: TextureUsages) -> Self {
+        self.0 |= usages;
+        self
+    }
+}
+
 #[derive(Component, Debug)]
 pub struct ExtractedCamera {
     pub target: Option<NormalizedRenderTarget>,

crates/bevy_render/src/render_resource/bind_group_entries.rs

@@ -147,6 +147,13 @@ impl<'a> IntoBinding<'a> for &'a TextureView {
     }
 }
 
+impl<'a> IntoBinding<'a> for &'a wgpu::TextureView {
+    #[inline]
+    fn into_binding(self) -> BindingResource<'a> {
+        BindingResource::TextureView(self)
+    }
+}
+
 impl<'a> IntoBinding<'a> for &'a [&'a wgpu::TextureView] {
     #[inline]
     fn into_binding(self) -> BindingResource<'a> {
@@ -161,6 +168,13 @@ impl<'a> IntoBinding<'a> for &'a Sampler {
     }
 }
 
+impl<'a> IntoBinding<'a> for &'a [&'a wgpu::Sampler] {
+    #[inline]
+    fn into_binding(self) -> BindingResource<'a> {
+        BindingResource::SamplerArray(self)
+    }
+}
+
 impl<'a> IntoBinding<'a> for BindingResource<'a> {
     #[inline]
     fn into_binding(self) -> BindingResource<'a> {
@@ -175,6 +189,13 @@ impl<'a> IntoBinding<'a> for wgpu::BufferBinding<'a> {
     }
 }
 
+impl<'a> IntoBinding<'a> for &'a [wgpu::BufferBinding<'a>] {
+    #[inline]
+    fn into_binding(self) -> BindingResource<'a> {
+        BindingResource::BufferArray(self)
+    }
+}
+
 pub trait IntoBindingArray<'b, const N: usize> {
     fn into_array(self) -> [BindingResource<'b>; N];
 }

crates/bevy_render/src/render_resource/bind_group_layout_entries.rs

@@ -568,4 +568,8 @@ pub mod binding_types {
         }
         .into_bind_group_layout_entry_builder()
     }
+
+    pub fn acceleration_structure() -> BindGroupLayoutEntryBuilder {
+        BindingType::AccelerationStructure.into_bind_group_layout_entry_builder()
+    }
 }

crates/bevy_render/src/render_resource/mod.rs

@@ -38,18 +38,21 @@ pub use wgpu::{
         BufferInitDescriptor, DispatchIndirectArgs, DrawIndexedIndirectArgs, DrawIndirectArgs,
         TextureDataOrder,
     },
-    AdapterInfo as WgpuAdapterInfo, AddressMode, AstcBlock, AstcChannel, BindGroupDescriptor,
+    AccelerationStructureFlags, AccelerationStructureGeometryFlags,
-    BindGroupEntry, BindGroupLayoutDescriptor, BindGroupLayoutEntry, BindingResource, BindingType,
+    AccelerationStructureUpdateMode, AdapterInfo as WgpuAdapterInfo, AddressMode, AstcBlock,
+    AstcChannel, BindGroupDescriptor, BindGroupEntry, BindGroupLayoutDescriptor,
+    BindGroupLayoutEntry, BindingResource, BindingType, Blas, BlasBuildEntry, BlasGeometries,
+    BlasGeometrySizeDescriptors, BlasTriangleGeometry, BlasTriangleGeometrySizeDescriptor,
     BlendComponent, BlendFactor, BlendOperation, BlendState, BufferAddress, BufferAsyncError,
     BufferBinding, BufferBindingType, BufferDescriptor, BufferSize, BufferUsages, ColorTargetState,
     ColorWrites, CommandEncoder, CommandEncoderDescriptor, CompareFunction, ComputePass,
     ComputePassDescriptor, ComputePipelineDescriptor as RawComputePipelineDescriptor,
-    DepthBiasState, DepthStencilState, DownlevelFlags, Extent3d, Face, Features as WgpuFeatures,
+    CreateBlasDescriptor, CreateTlasDescriptor, DepthBiasState, DepthStencilState, DownlevelFlags,
-    FilterMode, FragmentState as RawFragmentState, FrontFace, ImageSubresourceRange, IndexFormat,
+    Extent3d, Face, Features as WgpuFeatures, FilterMode, FragmentState as RawFragmentState,
-    Limits as WgpuLimits, LoadOp, Maintain, MapMode, MultisampleState, Operations, Origin3d,
+    FrontFace, ImageSubresourceRange, IndexFormat, Limits as WgpuLimits, LoadOp, Maintain, MapMode,
-    PipelineCompilationOptions, PipelineLayout, PipelineLayoutDescriptor, PolygonMode,
+    MultisampleState, Operations, Origin3d, PipelineCompilationOptions, PipelineLayout,
-    PrimitiveState, PrimitiveTopology, PushConstantRange, RenderPassColorAttachment,
+    PipelineLayoutDescriptor, PolygonMode, PrimitiveState, PrimitiveTopology, PushConstantRange,
-    RenderPassDepthStencilAttachment, RenderPassDescriptor,
+    RenderPassColorAttachment, RenderPassDepthStencilAttachment, RenderPassDescriptor,
     RenderPipelineDescriptor as RawRenderPipelineDescriptor, Sampler as WgpuSampler,
     SamplerBindingType, SamplerBindingType as WgpuSamplerBindingType, SamplerDescriptor,
     ShaderModule, ShaderModuleDescriptor, ShaderSource, ShaderStages, StencilFaceState,
@@ -57,8 +60,9 @@ pub use wgpu::{
     TexelCopyBufferLayout, TexelCopyTextureInfo, TextureAspect, TextureDescriptor,
     TextureDimension, TextureFormat, TextureFormatFeatureFlags, TextureFormatFeatures,
     TextureSampleType, TextureUsages, TextureView as WgpuTextureView, TextureViewDescriptor,
-    TextureViewDimension, VertexAttribute, VertexBufferLayout as RawVertexBufferLayout,
+    TextureViewDimension, Tlas, TlasInstance, TlasPackage, VertexAttribute,
-    VertexFormat, VertexState as RawVertexState, VertexStepMode, COPY_BUFFER_ALIGNMENT,
+    VertexBufferLayout as RawVertexBufferLayout, VertexFormat, VertexState as RawVertexState,
+    VertexStepMode, COPY_BUFFER_ALIGNMENT,
 };
 
 pub use crate::mesh::VertexBufferLayout;

crates/bevy_render/src/sync_world.rs

@@ -94,14 +94,14 @@ impl Plugin for SyncWorldPlugin {
         app.init_resource::<PendingSyncEntity>();
         app.add_observer(
             |trigger: Trigger<OnAdd, SyncToRenderWorld>, mut pending: ResMut<PendingSyncEntity>| {
-                pending.push(EntityRecord::Added(trigger.target()));
+                pending.push(EntityRecord::Added(trigger.target().unwrap()));
             },
         );
         app.add_observer(
             |trigger: Trigger<OnRemove, SyncToRenderWorld>,
              mut pending: ResMut<PendingSyncEntity>,
              query: Query<&RenderEntity>| {
-                if let Ok(e) = query.get(trigger.target()) {
+                if let Ok(e) = query.get(trigger.target().unwrap()) {
                     pending.push(EntityRecord::Removed(*e));
                 };
             },
@@ -512,14 +512,14 @@ mod tests {
 
         main_world.add_observer(
             |trigger: Trigger<OnAdd, SyncToRenderWorld>, mut pending: ResMut<PendingSyncEntity>| {
-                pending.push(EntityRecord::Added(trigger.target()));
+                pending.push(EntityRecord::Added(trigger.target().unwrap()));
             },
         );
         main_world.add_observer(
             |trigger: Trigger<OnRemove, SyncToRenderWorld>,
              mut pending: ResMut<PendingSyncEntity>,
              query: Query<&RenderEntity>| {
-                if let Ok(e) = query.get(trigger.target()) {
+                if let Ok(e) = query.get(trigger.target().unwrap()) {
                     pending.push(EntityRecord::Removed(*e));
                 };
             },

crates/bevy_scene/src/scene_spawner.rs

@@ -721,7 +721,7 @@ mod tests {
             .expect("Failed to run dynamic scene builder system.")
     }
 
-    fn observe_trigger(app: &mut App, scene_id: InstanceId, scene_entity: Entity) {
+    fn observe_trigger(app: &mut App, scene_id: InstanceId, scene_entity: Option<Entity>) {
         // Add observer
         app.world_mut().add_observer(
             move |trigger: Trigger<SceneInstanceReady>,
@@ -773,7 +773,7 @@ mod tests {
             .unwrap();
 
         // Check trigger.
-        observe_trigger(&mut app, scene_id, Entity::PLACEHOLDER);
+        observe_trigger(&mut app, scene_id, None);
     }
 
     #[test]
@@ -792,7 +792,7 @@ mod tests {
             .unwrap();
 
         // Check trigger.
-        observe_trigger(&mut app, scene_id, Entity::PLACEHOLDER);
+        observe_trigger(&mut app, scene_id, None);
     }
 
     #[test]
@@ -816,7 +816,7 @@ mod tests {
             .unwrap();
 
         // Check trigger.
-        observe_trigger(&mut app, scene_id, scene_entity);
+        observe_trigger(&mut app, scene_id, Some(scene_entity));
     }
 
     #[test]
@@ -840,7 +840,7 @@ mod tests {
             .unwrap();
 
         // Check trigger.
-        observe_trigger(&mut app, scene_id, scene_entity);
+        observe_trigger(&mut app, scene_id, Some(scene_entity));
     }
 
     #[test]

crates/bevy_ui/src/accessibility.rs

@@ -1,6 +1,7 @@
 use crate::{
     experimental::UiChildren,
     prelude::{Button, Label},
+    ui_transform::UiGlobalTransform,
     widget::{ImageNode, TextUiReader},
     ComputedNode,
 };
@@ -13,11 +14,9 @@ use bevy_ecs::{
     system::{Commands, Query},
     world::Ref,
 };
-use bevy_math::Vec3Swizzles;
-use bevy_render::camera::CameraUpdateSystems;
-use bevy_transform::prelude::GlobalTransform;
 
 use accesskit::{Node, Rect, Role};
+use bevy_render::camera::CameraUpdateSystems;
 
 fn calc_label(
     text_reader: &mut TextUiReader,
@@ -40,12 +39,12 @@ fn calc_bounds(
     mut nodes: Query<(
         &mut AccessibilityNode,
         Ref<ComputedNode>,
-        Ref<GlobalTransform>,
+        Ref<UiGlobalTransform>,
     )>,
 ) {
     for (mut accessible, node, transform) in &mut nodes {
         if node.is_changed() || transform.is_changed() {
-            let center = transform.translation().xy();
+            let center = transform.translation;
             let half_size = 0.5 * node.size;
             let min = center - half_size;
             let max = center + half_size;

crates/bevy_ui/src/focus.rs

@@ -1,18 +1,21 @@
-use crate::{CalculatedClip, ComputedNode, ComputedNodeTarget, ResolvedBorderRadius, UiStack};
+use crate::{
+    picking_backend::clip_check_recursive, ui_transform::UiGlobalTransform, ComputedNode,
+    ComputedNodeTarget, Node, UiStack,
+};
 use bevy_ecs::{
     change_detection::DetectChangesMut,
     entity::{ContainsEntity, Entity},
+    hierarchy::ChildOf,
     prelude::{Component, With},
     query::QueryData,
     reflect::ReflectComponent,
     system::{Local, Query, Res},
 };
 use bevy_input::{mouse::MouseButton, touch::Touches, ButtonInput};
-use bevy_math::{Rect, Vec2};
+use bevy_math::Vec2;
 use bevy_platform::collections::HashMap;
 use bevy_reflect::{std_traits::ReflectDefault, Reflect};
 use bevy_render::{camera::NormalizedRenderTarget, prelude::Camera, view::InheritedVisibility};
-use bevy_transform::components::GlobalTransform;
 use bevy_window::{PrimaryWindow, Window};
 
 use smallvec::SmallVec;
@@ -67,12 +70,12 @@ impl Default for Interaction {
     }
 }
 
-/// A component storing the position of the mouse relative to the node, (0., 0.) being the top-left corner and (1., 1.) being the bottom-right
+/// A component storing the position of the mouse relative to the node, (0., 0.) being the center and (0.5, 0.5) being the bottom-right
-/// If the mouse is not over the node, the value will go beyond the range of (0., 0.) to (1., 1.)
+/// If the mouse is not over the node, the value will go beyond the range of (-0.5, -0.5) to (0.5, 0.5)
 ///
 /// It can be used alongside [`Interaction`] to get the position of the press.
 ///
-/// The component is updated when it is in the same entity with [`Node`](crate::Node).
+/// The component is updated when it is in the same entity with [`Node`].
 #[derive(Component, Copy, Clone, Default, PartialEq, Debug, Reflect)]
 #[reflect(Component, Default, PartialEq, Debug, Clone)]
 #[cfg_attr(
@@ -81,8 +84,8 @@ impl Default for Interaction {
     reflect(Serialize, Deserialize)
 )]
 pub struct RelativeCursorPosition {
-    /// Visible area of the Node relative to the size of the entire Node.
+    /// True if the cursor position is over an unclipped area of the Node.
-    pub normalized_visible_node_rect: Rect,
+    pub cursor_over: bool,
     /// Cursor position relative to the size and position of the Node.
     /// A None value indicates that the cursor position is unknown.
     pub normalized: Option<Vec2>,
@@ -90,9 +93,8 @@ pub struct RelativeCursorPosition {
 
 impl RelativeCursorPosition {
     /// A helper function to check if the mouse is over the node
-    pub fn mouse_over(&self) -> bool {
+    pub fn cursor_over(&self) -> bool {
-        self.normalized
+        self.cursor_over
-            .is_some_and(|position| self.normalized_visible_node_rect.contains(position))
     }
 }
 
@@ -133,11 +135,10 @@ pub struct State {
 pub struct NodeQuery {
     entity: Entity,
     node: &'static ComputedNode,
-    global_transform: &'static GlobalTransform,
+    transform: &'static UiGlobalTransform,
     interaction: Option<&'static mut Interaction>,
     relative_cursor_position: Option<&'static mut RelativeCursorPosition>,
     focus_policy: Option<&'static FocusPolicy>,
-    calculated_clip: Option<&'static CalculatedClip>,
     inherited_visibility: Option<&'static InheritedVisibility>,
     target_camera: &'static ComputedNodeTarget,
 }
@@ -154,6 +155,8 @@ pub fn ui_focus_system(
     touches_input: Res<Touches>,
     ui_stack: Res<UiStack>,
     mut node_query: Query<NodeQuery>,
+    clipping_query: Query<(&ComputedNode, &UiGlobalTransform, &Node)>,
+    child_of_query: Query<&ChildOf>,
 ) {
     let primary_window = primary_window.iter().next();
 
@@ -234,46 +237,30 @@ pub fn ui_focus_system(
             }
             let camera_entity = node.target_camera.camera()?;
 
-            let node_rect = Rect::from_center_size(
-                node.global_transform.translation().truncate(),
-                node.node.size(),
-            );
-
-            // Intersect with the calculated clip rect to find the bounds of the visible region of the node
-            let visible_rect = node
-                .calculated_clip
-                .map(|clip| node_rect.intersect(clip.clip))
-                .unwrap_or(node_rect);
-
             let cursor_position = camera_cursor_positions.get(&camera_entity);
 
+            let contains_cursor = cursor_position.is_some_and(|point| {
+                node.node.contains_point(*node.transform, *point)
+                    && clip_check_recursive(*point, *entity, &clipping_query, &child_of_query)
+            });
+
             // The mouse position relative to the node
-            // (0., 0.) is the top-left corner, (1., 1.) is the bottom-right corner
+            // (-0.5, -0.5) is the top-left corner, (0.5, 0.5) is the bottom-right corner
             // Coordinates are relative to the entire node, not just the visible region.
-            let relative_cursor_position = cursor_position.and_then(|cursor_position| {
+            let normalized_cursor_position = cursor_position.and_then(|cursor_position| {
                 // ensure node size is non-zero in all dimensions, otherwise relative position will be
                 // +/-inf. if the node is hidden, the visible rect min/max will also be -inf leading to
                 // false positives for mouse_over (#12395)
-                (node_rect.size().cmpgt(Vec2::ZERO).all())
+                node.node.normalize_point(*node.transform, *cursor_position)
-                    .then_some((*cursor_position - node_rect.min) / node_rect.size())
             });
 
             // If the current cursor position is within the bounds of the node's visible area, consider it for
             // clicking
             let relative_cursor_position_component = RelativeCursorPosition {
-                normalized_visible_node_rect: visible_rect.normalize(node_rect),
+                cursor_over: contains_cursor,
-                normalized: relative_cursor_position,
+                normalized: normalized_cursor_position,
             };
 
-            let contains_cursor = relative_cursor_position_component.mouse_over()
-                && cursor_position.is_some_and(|point| {
-                    pick_rounded_rect(
-                        *point - node_rect.center(),
-                        node_rect.size(),
-                        node.node.border_radius,
-                    )
-                });
-
             // Save the relative cursor position to the correct component
             if let Some(mut node_relative_cursor_position_component) = node.relative_cursor_position
             {
@@ -284,7 +271,8 @@ pub fn ui_focus_system(
                 Some(*entity)
             } else {
                 if let Some(mut interaction) = node.interaction {
-                    if *interaction == Interaction::Hovered || (relative_cursor_position.is_none())
+                    if *interaction == Interaction::Hovered
+                        || (normalized_cursor_position.is_none())
                     {
                         interaction.set_if_neq(Interaction::None);
                     }
@@ -334,26 +322,3 @@ pub fn ui_focus_system(
         }
     }
 }
-
-// Returns true if `point` (relative to the rectangle's center) is within the bounds of a rounded rectangle with
-// the given size and border radius.
-//
-// Matches the sdf function in `ui.wgsl` that is used by the UI renderer to draw rounded rectangles.
-pub(crate) fn pick_rounded_rect(
-    point: Vec2,
-    size: Vec2,
-    border_radius: ResolvedBorderRadius,
-) -> bool {
-    let [top, bottom] = if point.x < 0. {
-        [border_radius.top_left, border_radius.bottom_left]
-    } else {
-        [border_radius.top_right, border_radius.bottom_right]
-    };
-    let r = if point.y < 0. { top } else { bottom };
-
-    let corner_to_point = point.abs() - 0.5 * size;
-    let q = corner_to_point + r;
-    let l = q.max(Vec2::ZERO).length();
-    let m = q.max_element().min(0.);
-    l + m - r < 0.
-}

crates/bevy_ui/src/layout/convert.rs

@@ -448,6 +448,8 @@ impl RepeatedGridTrack {
 
 #[cfg(test)]
 mod tests {
+    use bevy_math::Vec2;
+
     use super::*;
 
     #[test]
@@ -523,7 +525,7 @@ mod tests {
             grid_column: GridPlacement::start(4),
             grid_row: GridPlacement::span(3),
         };
-        let viewport_values = LayoutContext::new(1.0, bevy_math::Vec2::new(800., 600.));
+        let viewport_values = LayoutContext::new(1.0, Vec2::new(800., 600.));
         let taffy_style = from_node(&node, &viewport_values, false);
         assert_eq!(taffy_style.display, taffy::style::Display::Flex);
         assert_eq!(taffy_style.box_sizing, taffy::style::BoxSizing::ContentBox);
@@ -661,7 +663,7 @@ mod tests {
     #[test]
     fn test_into_length_percentage() {
         use taffy::style::LengthPercentage;
-        let context = LayoutContext::new(2.0, bevy_math::Vec2::new(800., 600.));
+        let context = LayoutContext::new(2.0, Vec2::new(800., 600.));
         let cases = [
             (Val::Auto, LengthPercentage::Length(0.)),
             (Val::Percent(1.), LengthPercentage::Percent(0.01)),

crates/bevy_ui/src/layout/mod.rs

@@ -1,5 +1,6 @@
 use crate::{
     experimental::{UiChildren, UiRootNodes},
+    ui_transform::{UiGlobalTransform, UiTransform},
     BorderRadius, ComputedNode, ComputedNodeTarget, ContentSize, Display, LayoutConfig, Node,
     Outline, OverflowAxis, ScrollPosition,
 };
@@ -12,9 +13,9 @@ use bevy_ecs::{
     system::{Commands, Query, ResMut},
     world::Ref,
 };
-use bevy_math::Vec2;
+
+use bevy_math::{Affine2, Vec2};
 use bevy_sprite::BorderRect;
-use bevy_transform::components::Transform;
 use thiserror::Error;
 use tracing::warn;
 use ui_surface::UiSurface;
@@ -81,9 +82,10 @@ pub fn ui_layout_system(
     )>,
     computed_node_query: Query<(Entity, Option<Ref<ChildOf>>), With<ComputedNode>>,
     ui_children: UiChildren,
-    mut node_transform_query: Query<(
+    mut node_update_query: Query<(
         &mut ComputedNode,
-        &mut Transform,
+        &UiTransform,
+        &mut UiGlobalTransform,
         &Node,
         Option<&LayoutConfig>,
         Option<&BorderRadius>,
@@ -175,7 +177,8 @@ with UI components as a child of an entity without UI components, your UI layout
             &mut ui_surface,
             true,
             computed_target.physical_size().as_vec2(),
-            &mut node_transform_query,
+            Affine2::IDENTITY,
+            &mut node_update_query,
             &ui_children,
             computed_target.scale_factor.recip(),
             Vec2::ZERO,
@@ -190,9 +193,11 @@ with UI components as a child of an entity without UI components, your UI layout
         ui_surface: &mut UiSurface,
         inherited_use_rounding: bool,
         target_size: Vec2,
-        node_transform_query: &mut Query<(
+        mut inherited_transform: Affine2,
+        node_update_query: &mut Query<(
             &mut ComputedNode,
-            &mut Transform,
+            &UiTransform,
+            &mut UiGlobalTransform,
             &Node,
             Option<&LayoutConfig>,
             Option<&BorderRadius>,
@@ -206,13 +211,14 @@ with UI components as a child of an entity without UI components, your UI layout
     ) {
         if let Ok((
             mut node,
-            mut transform,
+            transform,
+            mut global_transform,
             style,
             maybe_layout_config,
             maybe_border_radius,
             maybe_outline,
             maybe_scroll_position,
-        )) = node_transform_query.get_mut(entity)
+        )) = node_update_query.get_mut(entity)
         {
             let use_rounding = maybe_layout_config
                 .map(|layout_config| layout_config.use_rounding)
@@ -224,10 +230,11 @@ with UI components as a child of an entity without UI components, your UI layout
 
             let layout_size = Vec2::new(layout.size.width, layout.size.height);
 
+            // Taffy layout position of the top-left corner of the node, relative to its parent.
             let layout_location = Vec2::new(layout.location.x, layout.location.y);
 
-            // The position of the center of the node, stored in the node's transform
+            // The position of the center of the node relative to its top-left corner.
-            let node_center =
+            let local_center =
                 layout_location - parent_scroll_position + 0.5 * (layout_size - parent_size);
 
             // only trigger change detection when the new values are different
@@ -253,6 +260,16 @@ with UI components as a child of an entity without UI components, your UI layout
             node.bypass_change_detection().border = taffy_rect_to_border_rect(layout.border);
             node.bypass_change_detection().padding = taffy_rect_to_border_rect(layout.padding);
 
+            // Computer the node's new global transform
+            let mut local_transform =
+                transform.compute_affine(inverse_target_scale_factor, layout_size, target_size);
+            local_transform.translation += local_center;
+            inherited_transform *= local_transform;
+
+            if inherited_transform != **global_transform {
+                *global_transform = inherited_transform.into();
+            }
+
             if let Some(border_radius) = maybe_border_radius {
                 // We don't trigger change detection for changes to border radius
                 node.bypass_change_detection().border_radius = border_radius.resolve(
@@ -290,10 +307,6 @@ with UI components as a child of an entity without UI components, your UI layout
                     .max(0.);
             }
 
-            if transform.translation.truncate() != node_center {
-                transform.translation = node_center.extend(0.);
-            }
-
             let scroll_position: Vec2 = maybe_scroll_position
                 .map(|scroll_pos| {
                     Vec2::new(
@@ -333,7 +346,8 @@ with UI components as a child of an entity without UI components, your UI layout
                     ui_surface,
                     use_rounding,
                     target_size,
-                    node_transform_query,
+                    inherited_transform,
+                    node_update_query,
                     ui_children,
                     inverse_target_scale_factor,
                     layout_size,
@@ -356,10 +370,7 @@ mod tests {
     use bevy_platform::collections::HashMap;
     use bevy_render::{camera::ManualTextureViews, prelude::Camera};
     use bevy_transform::systems::mark_dirty_trees;
-    use bevy_transform::{
+    use bevy_transform::systems::{propagate_parent_transforms, sync_simple_transforms};
-        prelude::GlobalTransform,
-        systems::{propagate_parent_transforms, sync_simple_transforms},
-    };
     use bevy_utils::prelude::default;
     use bevy_window::{
         PrimaryWindow, Window, WindowCreated, WindowResized, WindowResolution,
@@ -684,23 +695,20 @@ mod tests {
         ui_schedule.run(&mut world);
 
         let overlap_check = world
-            .query_filtered::<(Entity, &ComputedNode, &GlobalTransform), Without<ChildOf>>()
+            .query_filtered::<(Entity, &ComputedNode, &UiGlobalTransform), Without<ChildOf>>()
             .iter(&world)
             .fold(
                 Option::<(Rect, bool)>::None,
-                |option_rect, (entity, node, global_transform)| {
+                |option_rect, (entity, node, transform)| {
-                    let current_rect = Rect::from_center_size(
+                    let current_rect = Rect::from_center_size(transform.translation, node.size());
-                        global_transform.translation().truncate(),
-                        node.size(),
-                    );
                     assert!(
                         current_rect.height().abs() + current_rect.width().abs() > 0.,
                         "root ui node {entity} doesn't have a logical size"
                     );
                     assert_ne!(
-                        global_transform.affine(),
+                        *transform,
-                        GlobalTransform::default().affine(),
+                        UiGlobalTransform::default(),
-                        "root ui node {entity} global transform is not populated"
+                        "root ui node {entity} transform is not populated"
                     );
                     let Some((rect, is_overlapping)) = option_rect else {
                         return Some((current_rect, false));

crates/bevy_ui/src/lib.rs

@@ -18,6 +18,7 @@ pub mod widget;
 pub mod gradients;
 #[cfg(feature = "bevy_ui_picking_backend")]
 pub mod picking_backend;
+pub mod ui_transform;
 
 use bevy_derive::{Deref, DerefMut};
 #[cfg(feature = "bevy_ui_picking_backend")]
@@ -42,6 +43,7 @@ pub use measurement::*;
 pub use render::*;
 pub use ui_material::*;
 pub use ui_node::*;
+pub use ui_transform::*;
 
 use widget::{ImageNode, ImageNodeSize, ViewportNode};
 
@@ -64,6 +66,7 @@ pub mod prelude {
             gradients::*,
             ui_material::*,
             ui_node::*,
+            ui_transform::*,
             widget::{Button, ImageNode, Label, NodeImageMode, ViewportNode},
             Interaction, MaterialNode, UiMaterialPlugin, UiScale,
         },

crates/bevy_ui/src/picking_backend.rs

@@ -24,14 +24,13 @@
 
 #![deny(missing_docs)]
 
-use crate::{focus::pick_rounded_rect, prelude::*, UiStack};
+use crate::{prelude::*, ui_transform::UiGlobalTransform, UiStack};
 use bevy_app::prelude::*;
 use bevy_ecs::{prelude::*, query::QueryData};
-use bevy_math::{Rect, Vec2};
+use bevy_math::Vec2;
 use bevy_platform::collections::HashMap;
 use bevy_reflect::{std_traits::ReflectDefault, Reflect};
 use bevy_render::prelude::*;
-use bevy_transform::prelude::*;
 use bevy_window::PrimaryWindow;
 
 use bevy_picking::backend::prelude::*;
@@ -91,9 +90,8 @@ impl Plugin for UiPickingPlugin {
 pub struct NodeQuery {
     entity: Entity,
     node: &'static ComputedNode,
-    global_transform: &'static GlobalTransform,
+    transform: &'static UiGlobalTransform,
     pickable: Option<&'static Pickable>,
-    calculated_clip: Option<&'static CalculatedClip>,
     inherited_visibility: Option<&'static InheritedVisibility>,
     target_camera: &'static ComputedNodeTarget,
 }
@@ -110,6 +108,8 @@ pub fn ui_picking(
     ui_stack: Res<UiStack>,
     node_query: Query<NodeQuery>,
     mut output: EventWriter<PointerHits>,
+    clipping_query: Query<(&ComputedNode, &UiGlobalTransform, &Node)>,
+    child_of_query: Query<&ChildOf>,
 ) {
     // For each camera, the pointer and its position
     let mut pointer_pos_by_camera = HashMap::<Entity, HashMap<PointerId, Vec2>>::default();
@@ -181,43 +181,33 @@ pub fn ui_picking(
             continue;
         };
 
-        let node_rect = Rect::from_center_size(
-            node.global_transform.translation().truncate(),
-            node.node.size(),
-        );
-
         // Nodes with Display::None have a (0., 0.) logical rect and can be ignored
-        if node_rect.size() == Vec2::ZERO {
+        if node.node.size() == Vec2::ZERO {
             continue;
         }
 
-        // Intersect with the calculated clip rect to find the bounds of the visible region of the node
-        let visible_rect = node
-            .calculated_clip
-            .map(|clip| node_rect.intersect(clip.clip))
-            .unwrap_or(node_rect);
-
         let pointers_on_this_cam = pointer_pos_by_camera.get(&camera_entity);
 
-        // The mouse position relative to the node
+        // Find the normalized cursor position relative to the node.
-        // (0., 0.) is the top-left corner, (1., 1.) is the bottom-right corner
+        // (±0., 0.) is the center with the corners at points (±0.5, ±0.5).
         // Coordinates are relative to the entire node, not just the visible region.
         for (pointer_id, cursor_position) in pointers_on_this_cam.iter().flat_map(|h| h.iter()) {
-            let relative_cursor_position = (*cursor_position - node_rect.min) / node_rect.size();
+            if node.node.contains_point(*node.transform, *cursor_position)
-
+                && clip_check_recursive(
-            if visible_rect
+                    *cursor_position,
-                .normalize(node_rect)
+                    *node_entity,
-                .contains(relative_cursor_position)
+                    &clipping_query,
-                && pick_rounded_rect(
+                    &child_of_query,
-                    *cursor_position - node_rect.center(),
-                    node_rect.size(),
-                    node.node.border_radius,
                 )
             {
                 hit_nodes
                     .entry((camera_entity, *pointer_id))
                     .or_default()
-                    .push((*node_entity, relative_cursor_position));
+                    .push((
+                        *node_entity,
+                        node.transform.inverse().transform_point2(*cursor_position)
+                            / node.node.size(),
+                    ));
             }
         }
     }
@@ -262,3 +252,27 @@ pub fn ui_picking(
         output.write(PointerHits::new(*pointer, picks, order));
     }
 }
+
+/// Walk up the tree child-to-parent checking that `point` is not clipped by any ancestor node.
+pub fn clip_check_recursive(
+    point: Vec2,
+    entity: Entity,
+    clipping_query: &Query<'_, '_, (&ComputedNode, &UiGlobalTransform, &Node)>,
+    child_of_query: &Query<&ChildOf>,
+) -> bool {
+    if let Ok(child_of) = child_of_query.get(entity) {
+        let parent = child_of.0;
+        if let Ok((computed_node, transform, node)) = clipping_query.get(parent) {
+            if !computed_node
+                .resolve_clip_rect(node.overflow, node.overflow_clip_margin)
+                .contains(transform.inverse().transform_point2(point))
+            {
+                // The point is clipped and should be ignored by picking
+                return false;
+            }
+        }
+        return clip_check_recursive(point, parent, clipping_query, child_of_query);
+    }
+    // Reached root, point unclipped by all ancestors
+    true
+}

crates/bevy_ui/src/render/box_shadow.rs

@@ -2,6 +2,7 @@
 
 use core::{hash::Hash, ops::Range};
 
+use crate::prelude::UiGlobalTransform;
 use crate::{
     BoxShadow, BoxShadowSamples, CalculatedClip, ComputedNode, ComputedNodeTarget, RenderUiSystems,
     ResolvedBorderRadius, TransparentUi, Val,
@@ -18,7 +19,7 @@ use bevy_ecs::{
     },
 };
 use bevy_image::BevyDefault as _;
-use bevy_math::{vec2, FloatOrd, Mat4, Rect, Vec2, Vec3Swizzles, Vec4Swizzles};
+use bevy_math::{vec2, Affine2, FloatOrd, Rect, Vec2};
 use bevy_render::sync_world::MainEntity;
 use bevy_render::RenderApp;
 use bevy_render::{
@@ -29,7 +30,6 @@ use bevy_render::{
     view::*,
     Extract, ExtractSchedule, Render, RenderSystems,
 };
-use bevy_transform::prelude::GlobalTransform;
 use bytemuck::{Pod, Zeroable};
 
 use super::{stack_z_offsets, UiCameraMap, UiCameraView, QUAD_INDICES, QUAD_VERTEX_POSITIONS};
@@ -211,7 +211,7 @@ impl SpecializedRenderPipeline for BoxShadowPipeline {
 /// Description of a shadow to be sorted and queued for rendering
 pub struct ExtractedBoxShadow {
     pub stack_index: u32,
-    pub transform: Mat4,
+    pub transform: Affine2,
     pub bounds: Vec2,
     pub clip: Option<Rect>,
     pub extracted_camera_entity: Entity,
@@ -236,7 +236,7 @@ pub fn extract_shadows(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             &BoxShadow,
             Option<&CalculatedClip>,
@@ -302,7 +302,7 @@ pub fn extract_shadows(
             extracted_box_shadows.box_shadows.push(ExtractedBoxShadow {
                 render_entity: commands.spawn(TemporaryRenderEntity).id(),
                 stack_index: uinode.stack_index,
-                transform: transform.compute_matrix() * Mat4::from_translation(offset.extend(0.)),
+                transform: Affine2::from(transform) * Affine2::from_translation(offset),
                 color: drop_shadow.color.into(),
                 bounds: shadow_size + 6. * blur_radius,
                 clip: clip.map(|clip| clip.clip),
@@ -405,11 +405,15 @@ pub fn prepare_shadows(
                     .get(item.index)
                     .filter(|n| item.entity() == n.render_entity)
                 {
-                    let rect_size = box_shadow.bounds.extend(1.0);
+                    let rect_size = box_shadow.bounds;
 
                     // Specify the corners of the node
-                    let positions = QUAD_VERTEX_POSITIONS
+                    let positions = QUAD_VERTEX_POSITIONS.map(|pos| {
-                        .map(|pos| (box_shadow.transform * (pos * rect_size).extend(1.)).xyz());
+                        box_shadow
+                            .transform
+                            .transform_point2(pos * rect_size)
+                            .extend(0.)
+                    });
 
                     // Calculate the effect of clipping
                     // Note: this won't work with rotation/scaling, but that's much more complex (may need more that 2 quads)
@@ -443,7 +447,7 @@ pub fn prepare_shadows(
                         positions[3] + positions_diff[3].extend(0.),
                     ];
 
-                    let transformed_rect_size = box_shadow.transform.transform_vector3(rect_size);
+                    let transformed_rect_size = box_shadow.transform.transform_vector2(rect_size);
 
                     // Don't try to cull nodes that have a rotation
                     // In a rotation around the Z-axis, this value is 0.0 for an angle of 0.0 or π
@@ -492,7 +496,7 @@ pub fn prepare_shadows(
                             size: box_shadow.size.into(),
                             radius,
                             blur: box_shadow.blur_radius,
-                            bounds: rect_size.xy().into(),
+                            bounds: rect_size.into(),
                         });
                     }
 

crates/bevy_ui/src/render/debug_overlay.rs

@@ -1,5 +1,6 @@
 use crate::shader_flags;
 use crate::ui_node::ComputedNodeTarget;
+use crate::ui_transform::UiGlobalTransform;
 use crate::CalculatedClip;
 use crate::ComputedNode;
 use bevy_asset::AssetId;
@@ -16,7 +17,6 @@ use bevy_render::sync_world::TemporaryRenderEntity;
 use bevy_render::view::InheritedVisibility;
 use bevy_render::Extract;
 use bevy_sprite::BorderRect;
-use bevy_transform::components::GlobalTransform;
 
 use super::ExtractedUiItem;
 use super::ExtractedUiNode;
@@ -62,9 +62,9 @@ pub fn extract_debug_overlay(
         Query<(
             Entity,
             &ComputedNode,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
-            &GlobalTransform,
             &ComputedNodeTarget,
         )>,
     >,
@@ -76,7 +76,7 @@ pub fn extract_debug_overlay(
 
     let mut camera_mapper = camera_map.get_mapper();
 
-    for (entity, uinode, visibility, maybe_clip, transform, computed_target) in &uinode_query {
+    for (entity, uinode, transform, visibility, maybe_clip, computed_target) in &uinode_query {
         if !debug_options.show_hidden && !visibility.get() {
             continue;
         }
@@ -102,7 +102,7 @@ pub fn extract_debug_overlay(
             extracted_camera_entity,
             item: ExtractedUiItem::Node {
                 atlas_scaling: None,
-                transform: transform.compute_matrix(),
+                transform: transform.into(),
                 flip_x: false,
                 flip_y: false,
                 border: BorderRect::all(debug_options.line_width / uinode.inverse_scale_factor()),

crates/bevy_ui/src/render/gradient.rs

@@ -17,8 +17,9 @@ use bevy_ecs::{
 use bevy_image::prelude::*;
 use bevy_math::{
     ops::{cos, sin},
-    FloatOrd, Mat4, Rect, Vec2, Vec3Swizzles, Vec4Swizzles,
+    FloatOrd, Rect, Vec2,
 };
+use bevy_math::{Affine2, Vec2Swizzles};
 use bevy_render::sync_world::MainEntity;
 use bevy_render::{
     render_phase::*,
@@ -29,7 +30,6 @@ use bevy_render::{
     Extract, ExtractSchedule, Render, RenderSystems,
 };
 use bevy_sprite::BorderRect;
-use bevy_transform::prelude::GlobalTransform;
 use bytemuck::{Pod, Zeroable};
 
 use super::shader_flags::BORDER_ALL;
@@ -238,7 +238,7 @@ pub enum ResolvedGradient {
 
 pub struct ExtractedGradient {
     pub stack_index: u32,
-    pub transform: Mat4,
+    pub transform: Affine2,
     pub rect: Rect,
     pub clip: Option<Rect>,
     pub extracted_camera_entity: Entity,
@@ -354,7 +354,7 @@ pub fn extract_gradients(
             Entity,
             &ComputedNode,
             &ComputedNodeTarget,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             AnyOf<(&BackgroundGradient, &BorderGradient)>,
@@ -414,7 +414,7 @@ pub fn extract_gradients(
                             border_radius: uinode.border_radius,
                             border: uinode.border,
                             node_type,
-                            transform: transform.compute_matrix(),
+                            transform: transform.into(),
                         },
                         main_entity: entity.into(),
                         render_entity: commands.spawn(TemporaryRenderEntity).id(),
@@ -439,7 +439,7 @@ pub fn extract_gradients(
                         extracted_gradients.items.push(ExtractedGradient {
                             render_entity: commands.spawn(TemporaryRenderEntity).id(),
                             stack_index: uinode.stack_index,
-                            transform: transform.compute_matrix(),
+                            transform: transform.into(),
                             stops_range: range_start..extracted_color_stops.0.len(),
                             rect: Rect {
                                 min: Vec2::ZERO,
@@ -487,7 +487,7 @@ pub fn extract_gradients(
                         extracted_gradients.items.push(ExtractedGradient {
                             render_entity: commands.spawn(TemporaryRenderEntity).id(),
                             stack_index: uinode.stack_index,
-                            transform: transform.compute_matrix(),
+                            transform: transform.into(),
                             stops_range: range_start..extracted_color_stops.0.len(),
                             rect: Rect {
                                 min: Vec2::ZERO,
@@ -541,7 +541,7 @@ pub fn extract_gradients(
                         extracted_gradients.items.push(ExtractedGradient {
                             render_entity: commands.spawn(TemporaryRenderEntity).id(),
                             stack_index: uinode.stack_index,
-                            transform: transform.compute_matrix(),
+                            transform: transform.into(),
                             stops_range: range_start..extracted_color_stops.0.len(),
                             rect: Rect {
                                 min: Vec2::ZERO,
@@ -675,12 +675,16 @@ pub fn prepare_gradient(
                     *item.batch_range_mut() = item_index as u32..item_index as u32 + 1;
                     let uinode_rect = gradient.rect;
 
-                    let rect_size = uinode_rect.size().extend(1.0);
+                    let rect_size = uinode_rect.size();
 
                     // Specify the corners of the node
-                    let positions = QUAD_VERTEX_POSITIONS
+                    let positions = QUAD_VERTEX_POSITIONS.map(|pos| {
-                        .map(|pos| (gradient.transform * (pos * rect_size).extend(1.)).xyz());
+                        gradient
-                    let corner_points = QUAD_VERTEX_POSITIONS.map(|pos| pos.xy() * rect_size.xy());
+                            .transform
+                            .transform_point2(pos * rect_size)
+                            .extend(0.)
+                    });
+                    let corner_points = QUAD_VERTEX_POSITIONS.map(|pos| pos * rect_size);
 
                     // Calculate the effect of clipping
                     // Note: this won't work with rotation/scaling, but that's much more complex (may need more that 2 quads)
@@ -721,7 +725,7 @@ pub fn prepare_gradient(
                         corner_points[3] + positions_diff[3],
                     ];
 
-                    let transformed_rect_size = gradient.transform.transform_vector3(rect_size);
+                    let transformed_rect_size = gradient.transform.transform_vector2(rect_size);
 
                     // Don't try to cull nodes that have a rotation
                     // In a rotation around the Z-axis, this value is 0.0 for an angle of 0.0 or π

crates/bevy_ui/src/render/mod.rs

@@ -8,7 +8,9 @@ pub mod ui_texture_slice_pipeline;
 mod debug_overlay;
 mod gradient;
 
+use crate::prelude::UiGlobalTransform;
 use crate::widget::{ImageNode, ViewportNode};
+
 use crate::{
     BackgroundColor, BorderColor, BoxShadowSamples, CalculatedClip, ComputedNode,
     ComputedNodeTarget, Outline, ResolvedBorderRadius, TextShadow, UiAntiAlias,
@@ -22,7 +24,7 @@ use bevy_core_pipeline::{core_2d::Camera2d, core_3d::Camera3d};
 use bevy_ecs::prelude::*;
 use bevy_ecs::system::SystemParam;
 use bevy_image::prelude::*;
-use bevy_math::{FloatOrd, Mat4, Rect, UVec4, Vec2, Vec3, Vec3Swizzles, Vec4Swizzles};
+use bevy_math::{Affine2, FloatOrd, Mat4, Rect, UVec4, Vec2};
 use bevy_render::load_shader_library;
 use bevy_render::render_graph::{NodeRunError, RenderGraphContext};
 use bevy_render::render_phase::ViewSortedRenderPhases;
@@ -243,7 +245,7 @@ pub enum ExtractedUiItem {
         /// Ordering: left, top, right, bottom.
         border: BorderRect,
         node_type: NodeType,
-        transform: Mat4,
+        transform: Affine2,
     },
     /// A contiguous sequence of text glyphs from the same section
     Glyphs {
@@ -253,7 +255,7 @@ pub enum ExtractedUiItem {
 }
 
 pub struct ExtractedGlyph {
-    pub transform: Mat4,
+    pub transform: Affine2,
     pub rect: Rect,
 }
 
@@ -344,7 +346,7 @@ pub fn extract_uinode_background_colors(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -383,7 +385,7 @@ pub fn extract_uinode_background_colors(
             extracted_camera_entity,
             item: ExtractedUiItem::Node {
                 atlas_scaling: None,
-                transform: transform.compute_matrix(),
+                transform: transform.into(),
                 flip_x: false,
                 flip_y: false,
                 border: uinode.border(),
@@ -403,7 +405,7 @@ pub fn extract_uinode_images(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -467,7 +469,7 @@ pub fn extract_uinode_images(
             extracted_camera_entity,
             item: ExtractedUiItem::Node {
                 atlas_scaling,
-                transform: transform.compute_matrix(),
+                transform: transform.into(),
                 flip_x: image.flip_x,
                 flip_y: image.flip_y,
                 border: uinode.border,
@@ -487,7 +489,7 @@ pub fn extract_uinode_borders(
             Entity,
             &Node,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -503,7 +505,7 @@ pub fn extract_uinode_borders(
         entity,
         node,
         computed_node,
-        global_transform,
+        transform,
         inherited_visibility,
         maybe_clip,
         camera,
@@ -567,7 +569,7 @@ pub fn extract_uinode_borders(
                         extracted_camera_entity,
                         item: ExtractedUiItem::Node {
                             atlas_scaling: None,
-                            transform: global_transform.compute_matrix(),
+                            transform: transform.into(),
                             flip_x: false,
                             flip_y: false,
                             border: computed_node.border(),
@@ -600,7 +602,7 @@ pub fn extract_uinode_borders(
                 clip: maybe_clip.map(|clip| clip.clip),
                 extracted_camera_entity,
                 item: ExtractedUiItem::Node {
-                    transform: global_transform.compute_matrix(),
+                    transform: transform.into(),
                     atlas_scaling: None,
                     flip_x: false,
                     flip_y: false,
@@ -749,7 +751,7 @@ pub fn extract_viewport_nodes(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -792,7 +794,7 @@ pub fn extract_viewport_nodes(
             extracted_camera_entity,
             item: ExtractedUiItem::Node {
                 atlas_scaling: None,
-                transform: transform.compute_matrix(),
+                transform: transform.into(),
                 flip_x: false,
                 flip_y: false,
                 border: uinode.border(),
@@ -812,7 +814,7 @@ pub fn extract_text_sections(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -830,7 +832,7 @@ pub fn extract_text_sections(
     for (
         entity,
         uinode,
-        global_transform,
+        transform,
         inherited_visibility,
         clip,
         camera,
@@ -847,8 +849,7 @@ pub fn extract_text_sections(
             continue;
         };
 
-        let transform = global_transform.affine()
+        let transform = Affine2::from(*transform) * Affine2::from_translation(-0.5 * uinode.size());
-            * bevy_math::Affine3A::from_translation((-0.5 * uinode.size()).extend(0.));
 
         for (
             i,
@@ -866,7 +867,7 @@ pub fn extract_text_sections(
                 .textures[atlas_info.location.glyph_index]
                 .as_rect();
             extracted_uinodes.glyphs.push(ExtractedGlyph {
-                transform: transform * Mat4::from_translation(position.extend(0.)),
+                transform: transform * Affine2::from_translation(*position),
                 rect,
             });
 
@@ -910,8 +911,8 @@ pub fn extract_text_shadows(
         Query<(
             Entity,
             &ComputedNode,
+            &UiGlobalTransform,
             &ComputedNodeTarget,
-            &GlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &TextLayoutInfo,
@@ -924,16 +925,8 @@ pub fn extract_text_shadows(
     let mut end = start + 1;
 
     let mut camera_mapper = camera_map.get_mapper();
-    for (
+    for (entity, uinode, transform, target, inherited_visibility, clip, text_layout_info, shadow) in
-        entity,
+        &uinode_query
-        uinode,
-        target,
-        global_transform,
-        inherited_visibility,
-        clip,
-        text_layout_info,
-        shadow,
-    ) in &uinode_query
     {
         // Skip if not visible or if size is set to zero (e.g. when a parent is set to `Display::None`)
         if !inherited_visibility.get() || uinode.is_empty() {
@@ -944,9 +937,9 @@ pub fn extract_text_shadows(
             continue;
         };
 
-        let transform = global_transform.affine()
+        let node_transform = Affine2::from(*transform)
-            * Mat4::from_translation(
+            * Affine2::from_translation(
-                (-0.5 * uinode.size() + shadow.offset / uinode.inverse_scale_factor()).extend(0.),
+                -0.5 * uinode.size() + shadow.offset / uinode.inverse_scale_factor(),
             );
 
         for (
@@ -965,7 +958,7 @@ pub fn extract_text_shadows(
                 .textures[atlas_info.location.glyph_index]
                 .as_rect();
             extracted_uinodes.glyphs.push(ExtractedGlyph {
-                transform: transform * Mat4::from_translation(position.extend(0.)),
+                transform: node_transform * Affine2::from_translation(*position),
                 rect,
             });
 
@@ -998,7 +991,7 @@ pub fn extract_text_background_colors(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -1021,8 +1014,8 @@ pub fn extract_text_background_colors(
             continue;
         };
 
-        let transform = global_transform.affine()
+        let transform =
-            * bevy_math::Affine3A::from_translation(-0.5 * uinode.size().extend(0.));
+            Affine2::from(global_transform) * Affine2::from_translation(-0.5 * uinode.size());
 
         for &(section_entity, rect) in text_layout_info.section_rects.iter() {
             let Ok(text_background_color) = text_background_colors_query.get(section_entity) else {
@@ -1042,7 +1035,7 @@ pub fn extract_text_background_colors(
                 extracted_camera_entity,
                 item: ExtractedUiItem::Node {
                     atlas_scaling: None,
-                    transform: transform * Mat4::from_translation(rect.center().extend(0.)),
+                    transform: transform * Affine2::from_translation(rect.center()),
                     flip_x: false,
                     flip_y: false,
                     border: uinode.border(),
@@ -1093,11 +1086,11 @@ impl Default for UiMeta {
     }
 }
 
-pub(crate) const QUAD_VERTEX_POSITIONS: [Vec3; 4] = [
+pub(crate) const QUAD_VERTEX_POSITIONS: [Vec2; 4] = [
-    Vec3::new(-0.5, -0.5, 0.0),
+    Vec2::new(-0.5, -0.5),
-    Vec3::new(0.5, -0.5, 0.0),
+    Vec2::new(0.5, -0.5),
-    Vec3::new(0.5, 0.5, 0.0),
+    Vec2::new(0.5, 0.5),
-    Vec3::new(-0.5, 0.5, 0.0),
+    Vec2::new(-0.5, 0.5),
 ];
 
 pub(crate) const QUAD_INDICES: [usize; 6] = [0, 2, 3, 0, 1, 2];
@@ -1321,12 +1314,12 @@ pub fn prepare_uinodes(
 
                             let mut uinode_rect = extracted_uinode.rect;
 
-                            let rect_size = uinode_rect.size().extend(1.0);
+                            let rect_size = uinode_rect.size();
 
                             // Specify the corners of the node
                             let positions = QUAD_VERTEX_POSITIONS
-                                .map(|pos| (*transform * (pos * rect_size).extend(1.)).xyz());
+                                .map(|pos| transform.transform_point2(pos * rect_size).extend(0.));
-                            let points = QUAD_VERTEX_POSITIONS.map(|pos| pos.xy() * rect_size.xy());
+                            let points = QUAD_VERTEX_POSITIONS.map(|pos| pos * rect_size);
 
                             // Calculate the effect of clipping
                             // Note: this won't work with rotation/scaling, but that's much more complex (may need more that 2 quads)
@@ -1367,7 +1360,7 @@ pub fn prepare_uinodes(
                                 points[3] + positions_diff[3],
                             ];
 
-                            let transformed_rect_size = transform.transform_vector3(rect_size);
+                            let transformed_rect_size = transform.transform_vector2(rect_size);
 
                             // Don't try to cull nodes that have a rotation
                             // In a rotation around the Z-axis, this value is 0.0 for an angle of 0.0 or π
@@ -1448,7 +1441,7 @@ pub fn prepare_uinodes(
                                         border_radius.bottom_left,
                                     ],
                                     border: [border.left, border.top, border.right, border.bottom],
-                                    size: rect_size.xy().into(),
+                                    size: rect_size.into(),
                                     point: points[i].into(),
                                 });
                             }
@@ -1470,13 +1463,14 @@ pub fn prepare_uinodes(
                             let color = extracted_uinode.color.to_f32_array();
                             for glyph in &extracted_uinodes.glyphs[range.clone()] {
                                 let glyph_rect = glyph.rect;
-                                let size = glyph.rect.size();
+                                let rect_size = glyph_rect.size();
-
-                                let rect_size = glyph_rect.size().extend(1.0);
 
                                 // Specify the corners of the glyph
                                 let positions = QUAD_VERTEX_POSITIONS.map(|pos| {
-                                    (glyph.transform * (pos * rect_size).extend(1.)).xyz()
+                                    glyph
+                                        .transform
+                                        .transform_point2(pos * glyph_rect.size())
+                                        .extend(0.)
                                 });
 
                                 let positions_diff = if let Some(clip) = extracted_uinode.clip {
@@ -1511,7 +1505,7 @@ pub fn prepare_uinodes(
 
                                 // cull nodes that are completely clipped
                                 let transformed_rect_size =
-                                    glyph.transform.transform_vector3(rect_size);
+                                    glyph.transform.transform_vector2(rect_size);
                                 if positions_diff[0].x - positions_diff[1].x
                                     >= transformed_rect_size.x.abs()
                                     || positions_diff[1].y - positions_diff[2].y
@@ -1548,7 +1542,7 @@ pub fn prepare_uinodes(
                                         flags: shader_flags::TEXTURED | shader_flags::CORNERS[i],
                                         radius: [0.0; 4],
                                         border: [0.0; 4],
-                                        size: size.into(),
+                                        size: rect_size.into(),
                                         point: [0.0; 2],
                                     });
                                 }

crates/bevy_ui/src/render/ui_material_pipeline.rs

@@ -1,9 +1,7 @@
-use core::{hash::Hash, marker::PhantomData, ops::Range};
-
 use crate::*;
 use bevy_asset::*;
 use bevy_ecs::{
-    prelude::Component,
+    prelude::{Component, With},
     query::ROQueryItem,
     system::{
         lifetimeless::{Read, SRes},
@@ -11,24 +9,22 @@ use bevy_ecs::{
     },
 };
 use bevy_image::BevyDefault as _;
-use bevy_math::{FloatOrd, Mat4, Rect, Vec2, Vec4Swizzles};
+use bevy_math::{Affine2, FloatOrd, Rect, Vec2};
 use bevy_render::{
     extract_component::ExtractComponentPlugin,
     globals::{GlobalsBuffer, GlobalsUniform},
+    load_shader_library,
     render_asset::{PrepareAssetError, RenderAsset, RenderAssetPlugin, RenderAssets},
     render_phase::*,
     render_resource::{binding_types::uniform_buffer, *},
     renderer::{RenderDevice, RenderQueue},
+    sync_world::{MainEntity, TemporaryRenderEntity},
     view::*,
     Extract, ExtractSchedule, Render, RenderSystems,
 };
-use bevy_render::{
-    load_shader_library,
-    sync_world::{MainEntity, TemporaryRenderEntity},
-};
 use bevy_sprite::BorderRect;
-use bevy_transform::prelude::GlobalTransform;
 use bytemuck::{Pod, Zeroable};
+use core::{hash::Hash, marker::PhantomData, ops::Range};
 
 /// Adds the necessary ECS resources and render logic to enable rendering entities using the given
 /// [`UiMaterial`] asset type (which includes [`UiMaterial`] types).
@@ -321,7 +317,7 @@ impl<P: PhaseItem, M: UiMaterial> RenderCommand<P> for DrawUiMaterialNode<M> {
 
 pub struct ExtractedUiMaterialNode<M: UiMaterial> {
     pub stack_index: u32,
-    pub transform: Mat4,
+    pub transform: Affine2,
     pub rect: Rect,
     pub border: BorderRect,
     pub border_radius: ResolvedBorderRadius,
@@ -356,7 +352,7 @@ pub fn extract_ui_material_nodes<M: UiMaterial>(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &MaterialNode<M>,
             &InheritedVisibility,
             Option<&CalculatedClip>,
@@ -387,7 +383,7 @@ pub fn extract_ui_material_nodes<M: UiMaterial>(
         extracted_uinodes.uinodes.push(ExtractedUiMaterialNode {
             render_entity: commands.spawn(TemporaryRenderEntity).id(),
             stack_index: computed_node.stack_index,
-            transform: transform.compute_matrix(),
+            transform: transform.into(),
             material: handle.id(),
             rect: Rect {
                 min: Vec2::ZERO,
@@ -459,10 +455,13 @@ pub fn prepare_uimaterial_nodes<M: UiMaterial>(
 
                     let uinode_rect = extracted_uinode.rect;
 
-                    let rect_size = uinode_rect.size().extend(1.0);
+                    let rect_size = uinode_rect.size();
 
                     let positions = QUAD_VERTEX_POSITIONS.map(|pos| {
-                        (extracted_uinode.transform * (pos * rect_size).extend(1.0)).xyz()
+                        extracted_uinode
+                            .transform
+                            .transform_point2(pos * rect_size)
+                            .extend(1.0)
                     });
 
                     let positions_diff = if let Some(clip) = extracted_uinode.clip {
@@ -496,7 +495,7 @@ pub fn prepare_uimaterial_nodes<M: UiMaterial>(
                     ];
 
                     let transformed_rect_size =
-                        extracted_uinode.transform.transform_vector3(rect_size);
+                        extracted_uinode.transform.transform_vector2(rect_size);
 
                     // Don't try to cull nodes that have a rotation
                     // In a rotation around the Z-axis, this value is 0.0 for an angle of 0.0 or π

crates/bevy_ui/src/render/ui_texture_slice_pipeline.rs

@@ -1,5 +1,6 @@
 use core::{hash::Hash, ops::Range};
 
+use crate::prelude::UiGlobalTransform;
 use crate::*;
 use bevy_asset::*;
 use bevy_color::{Alpha, ColorToComponents, LinearRgba};
@@ -11,7 +12,7 @@ use bevy_ecs::{
     },
 };
 use bevy_image::prelude::*;
-use bevy_math::{FloatOrd, Mat4, Rect, Vec2, Vec4Swizzles};
+use bevy_math::{Affine2, FloatOrd, Rect, Vec2};
 use bevy_platform::collections::HashMap;
 use bevy_render::sync_world::MainEntity;
 use bevy_render::{
@@ -25,7 +26,6 @@ use bevy_render::{
     Extract, ExtractSchedule, Render, RenderSystems,
 };
 use bevy_sprite::{SliceScaleMode, SpriteAssetEvents, SpriteImageMode, TextureSlicer};
-use bevy_transform::prelude::GlobalTransform;
 use binding_types::{sampler, texture_2d};
 use bytemuck::{Pod, Zeroable};
 use widget::ImageNode;
@@ -218,7 +218,7 @@ impl SpecializedRenderPipeline for UiTextureSlicePipeline {
 
 pub struct ExtractedUiTextureSlice {
     pub stack_index: u32,
-    pub transform: Mat4,
+    pub transform: Affine2,
     pub rect: Rect,
     pub atlas_rect: Option<Rect>,
     pub image: AssetId<Image>,
@@ -246,7 +246,7 @@ pub fn extract_ui_texture_slices(
         Query<(
             Entity,
             &ComputedNode,
-            &GlobalTransform,
+            &UiGlobalTransform,
             &InheritedVisibility,
             Option<&CalculatedClip>,
             &ComputedNodeTarget,
@@ -306,7 +306,7 @@ pub fn extract_ui_texture_slices(
         extracted_ui_slicers.slices.push(ExtractedUiTextureSlice {
             render_entity: commands.spawn(TemporaryRenderEntity).id(),
             stack_index: uinode.stack_index,
-            transform: transform.compute_matrix(),
+            transform: transform.into(),
             color: image.color.into(),
             rect: Rect {
                 min: Vec2::ZERO,
@@ -497,11 +497,12 @@ pub fn prepare_ui_slices(
 
                     let uinode_rect = texture_slices.rect;
 
-                    let rect_size = uinode_rect.size().extend(1.0);
+                    let rect_size = uinode_rect.size();
 
                     // Specify the corners of the node
-                    let positions = QUAD_VERTEX_POSITIONS
+                    let positions = QUAD_VERTEX_POSITIONS.map(|pos| {
-                        .map(|pos| (texture_slices.transform * (pos * rect_size).extend(1.)).xyz());
+                        (texture_slices.transform.transform_point2(pos * rect_size)).extend(0.)
+                    });
 
                     // Calculate the effect of clipping
                     // Note: this won't work with rotation/scaling, but that's much more complex (may need more that 2 quads)
@@ -536,7 +537,7 @@ pub fn prepare_ui_slices(
                     ];
 
                     let transformed_rect_size =
-                        texture_slices.transform.transform_vector3(rect_size);
+                        texture_slices.transform.transform_vector2(rect_size);
 
                     // Don't try to cull nodes that have a rotation
                     // In a rotation around the Z-axis, this value is 0.0 for an angle of 0.0 or π

crates/bevy_ui/src/ui_node.rs

@@ -1,4 +1,7 @@
-use crate::{FocusPolicy, UiRect, Val};
+use crate::{
+    ui_transform::{UiGlobalTransform, UiTransform},
+    FocusPolicy, UiRect, Val,
+};
 use bevy_color::{Alpha, Color};
 use bevy_derive::{Deref, DerefMut};
 use bevy_ecs::{prelude::*, system::SystemParam};
@@ -9,7 +12,6 @@ use bevy_render::{
     view::Visibility,
 };
 use bevy_sprite::BorderRect;
-use bevy_transform::components::Transform;
 use bevy_utils::once;
 use bevy_window::{PrimaryWindow, WindowRef};
 use core::{f32, num::NonZero};
@@ -229,6 +231,73 @@ impl ComputedNode {
     pub const fn inverse_scale_factor(&self) -> f32 {
         self.inverse_scale_factor
     }
+
+    // Returns true if `point` within the node.
+    //
+    // Matches the sdf function in `ui.wgsl` that is used by the UI renderer to draw rounded rectangles.
+    pub fn contains_point(&self, transform: UiGlobalTransform, point: Vec2) -> bool {
+        let Some(local_point) = transform
+            .try_inverse()
+            .map(|transform| transform.transform_point2(point))
+        else {
+            return false;
+        };
+        let [top, bottom] = if local_point.x < 0. {
+            [self.border_radius.top_left, self.border_radius.bottom_left]
+        } else {
+            [
+                self.border_radius.top_right,
+                self.border_radius.bottom_right,
+            ]
+        };
+        let r = if local_point.y < 0. { top } else { bottom };
+        let corner_to_point = local_point.abs() - 0.5 * self.size;
+        let q = corner_to_point + r;
+        let l = q.max(Vec2::ZERO).length();
+        let m = q.max_element().min(0.);
+        l + m - r < 0.
+    }
+
+    /// Transform a point to normalized node space with the center of the node at the origin and the corners at [+/-0.5, +/-0.5]
+    pub fn normalize_point(&self, transform: UiGlobalTransform, point: Vec2) -> Option<Vec2> {
+        self.size
+            .cmpgt(Vec2::ZERO)
+            .all()
+            .then(|| transform.try_inverse())
+            .flatten()
+            .map(|transform| transform.transform_point2(point) / self.size)
+    }
+
+    /// Resolve the node's clipping rect in local space
+    pub fn resolve_clip_rect(
+        &self,
+        overflow: Overflow,
+        overflow_clip_margin: OverflowClipMargin,
+    ) -> Rect {
+        let mut clip_rect = Rect::from_center_size(Vec2::ZERO, self.size);
+
+        let clip_inset = match overflow_clip_margin.visual_box {
+            OverflowClipBox::BorderBox => BorderRect::ZERO,
+            OverflowClipBox::ContentBox => self.content_inset(),
+            OverflowClipBox::PaddingBox => self.border(),
+        };
+
+        clip_rect.min.x += clip_inset.left;
+        clip_rect.min.y += clip_inset.top;
+        clip_rect.max.x -= clip_inset.right;
+        clip_rect.max.y -= clip_inset.bottom;
+
+        if overflow.x == OverflowAxis::Visible {
+            clip_rect.min.x = -f32::INFINITY;
+            clip_rect.max.x = f32::INFINITY;
+        }
+        if overflow.y == OverflowAxis::Visible {
+            clip_rect.min.y = -f32::INFINITY;
+            clip_rect.max.y = f32::INFINITY;
+        }
+
+        clip_rect
+    }
 }
 
 impl ComputedNode {
@@ -323,12 +392,12 @@ impl From<Vec2> for ScrollPosition {
 #[require(
     ComputedNode,
     ComputedNodeTarget,
+    UiTransform,
     BackgroundColor,
     BorderColor,
     BorderRadius,
     FocusPolicy,
     ScrollPosition,
-    Transform,
     Visibility,
     ZIndex
 )]

crates/bevy_ui/src/ui_transform.rs

@@ -0,0 +1,191 @@
+use crate::Val;
+use bevy_derive::Deref;
+use bevy_ecs::component::Component;
+use bevy_ecs::prelude::ReflectComponent;
+use bevy_math::Affine2;
+use bevy_math::Rot2;
+use bevy_math::Vec2;
+use bevy_reflect::prelude::*;
+
+/// A pair of [`Val`]s used to represent a 2-dimensional size or offset.
+#[derive(Debug, PartialEq, Clone, Copy, Reflect)]
+#[reflect(Default, PartialEq, Debug, Clone)]
+#[cfg_attr(
+    feature = "serialize",
+    derive(serde::Serialize, serde::Deserialize),
+    reflect(Serialize, Deserialize)
+)]
+pub struct Val2 {
+    /// Translate the node along the x-axis.
+    /// `Val::Percent` values are resolved based on the computed width of the Ui Node.
+    /// `Val::Auto` is resolved to `0.`.
+    pub x: Val,
+    /// Translate the node along the y-axis.
+    /// `Val::Percent` values are resolved based on the computed height of the UI Node.
+    /// `Val::Auto` is resolved to `0.`.
+    pub y: Val,
+}
+
+impl Val2 {
+    pub const ZERO: Self = Self {
+        x: Val::ZERO,
+        y: Val::ZERO,
+    };
+
+    /// Creates a new [`Val2`] where both components are in logical pixels
+    pub const fn px(x: f32, y: f32) -> Self {
+        Self {
+            x: Val::Px(x),
+            y: Val::Px(y),
+        }
+    }
+
+    /// Creates a new [`Val2`] where both components are percentage values
+    pub const fn percent(x: f32, y: f32) -> Self {
+        Self {
+            x: Val::Percent(x),
+            y: Val::Percent(y),
+        }
+    }
+
+    /// Creates a new [`Val2`]
+    pub const fn new(x: Val, y: Val) -> Self {
+        Self { x, y }
+    }
+
+    /// Resolves this [`Val2`] from the given `scale_factor`, `parent_size`,
+    /// and `viewport_size`.
+    ///
+    /// Component values of [`Val::Auto`] are resolved to 0.
+    pub fn resolve(&self, scale_factor: f32, base_size: Vec2, viewport_size: Vec2) -> Vec2 {
+        Vec2::new(
+            self.x
+                .resolve(scale_factor, base_size.x, viewport_size)
+                .unwrap_or(0.),
+            self.y
+                .resolve(scale_factor, base_size.y, viewport_size)
+                .unwrap_or(0.),
+        )
+    }
+}
+
+impl Default for Val2 {
+    fn default() -> Self {
+        Self::ZERO
+    }
+}
+
+/// Relative 2D transform for UI nodes
+///
+/// [`UiGlobalTransform`] is automatically inserted whenever [`UiTransform`] is inserted.
+#[derive(Component, Debug, PartialEq, Clone, Copy, Reflect)]
+#[reflect(Component, Default, PartialEq, Debug, Clone)]
+#[cfg_attr(
+    feature = "serialize",
+    derive(serde::Serialize, serde::Deserialize),
+    reflect(Serialize, Deserialize)
+)]
+#[require(UiGlobalTransform)]
+pub struct UiTransform {
+    /// Translate the node.
+    pub translation: Val2,
+    /// Scale the node. A negative value reflects the node in that axis.
+    pub scale: Vec2,
+    /// Rotate the node clockwise.
+    pub rotation: Rot2,
+}
+
+impl UiTransform {
+    pub const IDENTITY: Self = Self {
+        translation: Val2::ZERO,
+        scale: Vec2::ONE,
+        rotation: Rot2::IDENTITY,
+    };
+
+    /// Creates a UI transform representing a rotation.
+    pub fn from_rotation(rotation: Rot2) -> Self {
+        Self {
+            rotation,
+            ..Self::IDENTITY
+        }
+    }
+
+    /// Creates a UI transform representing a responsive translation.
+    pub fn from_translation(translation: Val2) -> Self {
+        Self {
+            translation,
+            ..Self::IDENTITY
+        }
+    }
+
+    /// Creates a UI transform representing a scaling.
+    pub fn from_scale(scale: Vec2) -> Self {
+        Self {
+            scale,
+            ..Self::IDENTITY
+        }
+    }
+
+    /// Resolves the translation from the given `scale_factor`, `base_value`, and `target_size`
+    /// and returns a 2d affine transform from the resolved translation, and the `UiTransform`'s rotation, and scale.
+    pub fn compute_affine(&self, scale_factor: f32, base_size: Vec2, target_size: Vec2) -> Affine2 {
+        Affine2::from_scale_angle_translation(
+            self.scale,
+            self.rotation.as_radians(),
+            self.translation
+                .resolve(scale_factor, base_size, target_size),
+        )
+    }
+}
+
+impl Default for UiTransform {
+    fn default() -> Self {
+        Self::IDENTITY
+    }
+}
+
+/// Absolute 2D transform for UI nodes
+///
+/// [`UiGlobalTransform`]s are updated from [`UiTransform`] and [`Node`](crate::ui_node::Node)
+///  in [`ui_layout_system`](crate::layout::ui_layout_system)
+#[derive(Component, Debug, PartialEq, Clone, Copy, Reflect, Deref)]
+#[reflect(Component, Default, PartialEq, Debug, Clone)]
+#[cfg_attr(
+    feature = "serialize",
+    derive(serde::Serialize, serde::Deserialize),
+    reflect(Serialize, Deserialize)
+)]
+pub struct UiGlobalTransform(Affine2);
+
+impl Default for UiGlobalTransform {
+    fn default() -> Self {
+        Self(Affine2::IDENTITY)
+    }
+}
+
+impl UiGlobalTransform {
+    /// If the transform is invertible returns its inverse.
+    /// Otherwise returns `None`.
+    #[inline]
+    pub fn try_inverse(&self) -> Option<Affine2> {
+        (self.matrix2.determinant() != 0.).then_some(self.inverse())
+    }
+}
+
+impl From<Affine2> for UiGlobalTransform {
+    fn from(value: Affine2) -> Self {
+        Self(value)
+    }
+}
+
+impl From<UiGlobalTransform> for Affine2 {
+    fn from(value: UiGlobalTransform) -> Self {
+        value.0
+    }
+}
+
+impl From<&UiGlobalTransform> for Affine2 {
+    fn from(value: &UiGlobalTransform) -> Self {
+        value.0
+    }
+}

crates/bevy_ui/src/update.rs

@@ -2,6 +2,7 @@
 
 use crate::{
     experimental::{UiChildren, UiRootNodes},
+    ui_transform::UiGlobalTransform,
     CalculatedClip, ComputedNodeTarget, DefaultUiCamera, Display, Node, OverflowAxis, UiScale,
     UiTargetCamera,
 };
@@ -17,7 +18,6 @@ use bevy_ecs::{
 use bevy_math::{Rect, UVec2};
 use bevy_render::camera::Camera;
 use bevy_sprite::BorderRect;
-use bevy_transform::components::GlobalTransform;
 
 /// Updates clipping for all nodes
 pub fn update_clipping_system(
@@ -26,7 +26,7 @@ pub fn update_clipping_system(
     mut node_query: Query<(
         &Node,
         &ComputedNode,
-        &GlobalTransform,
+        &UiGlobalTransform,
         Option<&mut CalculatedClip>,
     )>,
     ui_children: UiChildren,
@@ -48,14 +48,13 @@ fn update_clipping(
     node_query: &mut Query<(
         &Node,
         &ComputedNode,
-        &GlobalTransform,
+        &UiGlobalTransform,
         Option<&mut CalculatedClip>,
     )>,
     entity: Entity,
     mut maybe_inherited_clip: Option<Rect>,
 ) {
-    let Ok((node, computed_node, global_transform, maybe_calculated_clip)) =
+    let Ok((node, computed_node, transform, maybe_calculated_clip)) = node_query.get_mut(entity)
-        node_query.get_mut(entity)
     else {
         return;
     };
@@ -91,10 +90,7 @@ fn update_clipping(
         maybe_inherited_clip
     } else {
         // Find the current node's clipping rect and intersect it with the inherited clipping rect, if one exists
-        let mut clip_rect = Rect::from_center_size(
+        let mut clip_rect = Rect::from_center_size(transform.translation, computed_node.size());
-            global_transform.translation().truncate(),
-            computed_node.size(),
-        );
 
         // Content isn't clipped at the edges of the node but at the edges of the region specified by [`Node::overflow_clip_margin`].
         //

crates/bevy_ui/src/widget/viewport.rs

@@ -171,11 +171,6 @@ pub fn update_viewport_render_target_size(
             height: u32::max(1, size.y as u32),
             ..default()
         };
-        let image = images.get_mut(image_handle).unwrap();
+        images.get_mut(image_handle).unwrap().resize(size);
-        if image.data.is_some() {
-            image.resize(size);
-        } else {
-            image.texture_descriptor.size = size;
-        }
     }
 }

crates/bevy_winit/src/cursor.rs

@@ -194,7 +194,7 @@ fn update_cursors(
 fn on_remove_cursor_icon(trigger: Trigger<OnRemove, CursorIcon>, mut commands: Commands) {
     // Use `try_insert` to avoid panic if the window is being destroyed.
     commands
-        .entity(trigger.target())
+        .entity(trigger.target().unwrap())
         .try_insert(PendingCursor(Some(CursorSource::System(
             convert_system_cursor_icon(SystemCursorIcon::Default),
         ))));

examples/3d/edit_material_on_gltf.rs

@@ -65,12 +65,12 @@ fn change_material(
     mut asset_materials: ResMut<Assets<StandardMaterial>>,
 ) {
     // Get the `ColorOverride` of the entity, if it does not have a color override, skip
-    let Ok(color_override) = color_override.get(trigger.target()) else {
+    let Ok(color_override) = color_override.get(trigger.target().unwrap()) else {
         return;
     };
 
     // Iterate over all children recursively
-    for descendants in children.iter_descendants(trigger.target()) {
+    for descendants in children.iter_descendants(trigger.target().unwrap()) {
         // Get the material of the descendant
         if let Some(material) = mesh_materials
             .get(descendants)

examples/README.md

@@ -571,6 +571,7 @@ Example | Description
 [UI Texture Atlas Slice](../examples/ui/ui_texture_atlas_slice.rs) | Illustrates how to use 9 Slicing for TextureAtlases in UI
 [UI Texture Slice](../examples/ui/ui_texture_slice.rs) | Illustrates how to use 9 Slicing in UI
 [UI Texture Slice Flipping and Tiling](../examples/ui/ui_texture_slice_flip_and_tile.rs) | Illustrates how to flip and tile images with 9 Slicing in UI
+[UI Transform](../examples/ui/ui_transform.rs) | An example demonstrating how to translate, rotate and scale UI elements.
 [UI Z-Index](../examples/ui/z_index.rs) | Demonstrates how to control the relative depth (z-position) of UI elements
 [Viewport Debug](../examples/ui/viewport_debug.rs) | An example for debugging viewport coordinates
 [Viewport Node](../examples/ui/viewport_node.rs) | Demonstrates how to create a viewport node with picking support

examples/animation/animated_mesh.rs

@@ -70,12 +70,12 @@ fn play_animation_when_ready(
 ) {
     // The entity we spawned in `setup_mesh_and_animation` is the trigger's target.
     // Start by finding the AnimationToPlay component we added to that entity.
-    if let Ok(animation_to_play) = animations_to_play.get(trigger.target()) {
+    if let Ok(animation_to_play) = animations_to_play.get(trigger.target().unwrap()) {
         // The SceneRoot component will have spawned the scene as a hierarchy
         // of entities parented to our entity. Since the asset contained a skinned
         // mesh and animations, it will also have spawned an animation player
         // component. Search our entity's descendants to find the animation player.
-        for child in children.iter_descendants(trigger.target()) {
+        for child in children.iter_descendants(trigger.target().unwrap()) {
             if let Ok(mut player) = players.get_mut(child) {
                 // Tell the animation player to start the animation and keep
                 // repeating it.

examples/animation/animated_mesh_events.rs

@@ -47,7 +47,10 @@ fn observe_on_step(
     transforms: Query<&GlobalTransform>,
     mut seeded_rng: ResMut<SeededRng>,
 ) {
-    let translation = transforms.get(trigger.target()).unwrap().translation();
+    let translation = transforms
+        .get(trigger.target().unwrap())
+        .unwrap()
+        .translation();
     // Spawn a bunch of particles.
     for _ in 0..14 {
         let horizontal = seeded_rng.0.r#gen::<Dir2>() * seeded_rng.0.gen_range(8.0..12.0);

examples/ecs/entity_disabling.rs

@@ -40,7 +40,7 @@ fn disable_entities_on_click(
     valid_query: Query<&DisableOnClick>,
     mut commands: Commands,
 ) {
-    let clicked_entity = trigger.target();
+    let clicked_entity = trigger.target().unwrap();
     // Windows and text are entities and can be clicked!
     // We definitely don't want to disable the window itself,
     // because that would cause the app to close!

examples/ecs/observer_propagation.rs

@@ -78,14 +78,14 @@ fn attack_armor(entities: Query<Entity, With<Armor>>, mut commands: Commands) {
 }
 
 fn attack_hits(trigger: Trigger<Attack>, name: Query<&Name>) {
-    if let Ok(name) = name.get(trigger.target()) {
+    if let Ok(name) = name.get(trigger.target().unwrap()) {
         info!("Attack hit {}", name);
     }
 }
 
 /// A callback placed on [`Armor`], checking if it absorbed all the [`Attack`] damage.
 fn block_attack(mut trigger: Trigger<Attack>, armor: Query<(&Armor, &Name)>) {
-    let (armor, name) = armor.get(trigger.target()).unwrap();
+    let (armor, name) = armor.get(trigger.target().unwrap()).unwrap();
     let attack = trigger.event_mut();
     let damage = attack.damage.saturating_sub(**armor);
     if damage > 0 {
@@ -110,14 +110,14 @@ fn take_damage(
     mut app_exit: EventWriter<AppExit>,
 ) {
     let attack = trigger.event();
-    let (mut hp, name) = hp.get_mut(trigger.target()).unwrap();
+    let (mut hp, name) = hp.get_mut(trigger.target().unwrap()).unwrap();
     **hp = hp.saturating_sub(attack.damage);
 
     if **hp > 0 {
         info!("{} has {:.1} HP", name, hp.0);
     } else {
         warn!("💀 {} has died a gruesome death", name);
-        commands.entity(trigger.target()).despawn();
+        commands.entity(trigger.target().unwrap()).despawn();
         app_exit.write(AppExit::Success);
     }
 

examples/ecs/observers.rs

@@ -117,12 +117,16 @@ fn on_add_mine(
     query: Query<&Mine>,
     mut index: ResMut<SpatialIndex>,
 ) {
-    let mine = query.get(trigger.target()).unwrap();
+    let mine = query.get(trigger.target().unwrap()).unwrap();
     let tile = (
         (mine.pos.x / CELL_SIZE).floor() as i32,
         (mine.pos.y / CELL_SIZE).floor() as i32,
     );
-    index.map.entry(tile).or_default().insert(trigger.target());
+    index
+        .map
+        .entry(tile)
+        .or_default()
+        .insert(trigger.target().unwrap());
 }
 
 // Remove despawned mines from our index
@@ -131,19 +135,19 @@ fn on_remove_mine(
     query: Query<&Mine>,
     mut index: ResMut<SpatialIndex>,
 ) {
-    let mine = query.get(trigger.target()).unwrap();
+    let mine = query.get(trigger.target().unwrap()).unwrap();
     let tile = (
         (mine.pos.x / CELL_SIZE).floor() as i32,
         (mine.pos.y / CELL_SIZE).floor() as i32,
     );
     index.map.entry(tile).and_modify(|set| {
-        set.remove(&trigger.target());
+        set.remove(&trigger.target().unwrap());
     });
 }
 
 fn explode_mine(trigger: Trigger<Explode>, query: Query<&Mine>, mut commands: Commands) {
     // If a triggered event is targeting a specific entity you can access it with `.target()`
-    let id = trigger.target();
+    let id = trigger.target().unwrap();
     let Ok(mut entity) = commands.get_entity(id) else {
         return;
     };

examples/ecs/removal_detection.rs

@@ -50,7 +50,7 @@ fn remove_component(
 
 fn react_on_removal(trigger: Trigger<OnRemove, MyComponent>, mut query: Query<&mut Sprite>) {
     // The `OnRemove` trigger was automatically called on the `Entity` that had its `MyComponent` removed.
-    let entity = trigger.target();
+    let entity = trigger.target().unwrap();
     if let Ok(mut sprite) = query.get_mut(entity) {
         sprite.color = Color::srgb(0.5, 1., 1.);
     }

examples/no_std/library/src/lib.rs

@@ -127,7 +127,10 @@ fn tick_timers(
 }
 
 fn unwrap<B: Bundle>(trigger: Trigger<Unwrap>, world: &mut World) {
-    if let Ok(mut target) = world.get_entity_mut(trigger.target()) {
+    if let Some(mut target) = trigger
+        .target()
+        .and_then(|target| world.get_entity_mut(target).ok())
+    {
         if let Some(DelayedComponent(bundle)) = target.take::<DelayedComponent<B>>() {
             target.insert(bundle);
         }

examples/picking/debug_picking.rs

@@ -48,13 +48,13 @@ fn setup_scene(
         .observe(on_click_spawn_cube)
         .observe(
             |out: Trigger<Pointer<Out>>, mut texts: Query<&mut TextColor>| {
-                let mut text_color = texts.get_mut(out.target()).unwrap();
+                let mut text_color = texts.get_mut(out.target().unwrap()).unwrap();
                 text_color.0 = Color::WHITE;
             },
         )
         .observe(
             |over: Trigger<Pointer<Over>>, mut texts: Query<&mut TextColor>| {
-                let mut color = texts.get_mut(over.target()).unwrap();
+                let mut color = texts.get_mut(over.target().unwrap()).unwrap();
                 color.0 = bevy::color::palettes::tailwind::CYAN_400.into();
             },
         );
@@ -102,7 +102,7 @@ fn on_click_spawn_cube(
 }
 
 fn on_drag_rotate(drag: Trigger<Pointer<Drag>>, mut transforms: Query<&mut Transform>) {
-    if let Ok(mut transform) = transforms.get_mut(drag.target()) {
+    if let Ok(mut transform) = transforms.get_mut(drag.target().unwrap()) {
         transform.rotate_y(drag.delta.x * 0.02);
         transform.rotate_x(drag.delta.y * 0.02);
     }

examples/picking/mesh_picking.rs

@@ -164,7 +164,7 @@ fn update_material_on<E>(
     // versions of this observer, each triggered by a different event and with a different hardcoded
     // material. Instead, the event type is a generic, and the material is passed in.
     move |trigger, mut query| {
-        if let Ok(mut material) = query.get_mut(trigger.target()) {
+        if let Ok(mut material) = query.get_mut(trigger.target().unwrap()) {
             material.0 = new_material.clone();
         }
     }
@@ -191,7 +191,7 @@ fn rotate(mut query: Query<&mut Transform, With<Shape>>, time: Res<Time>) {
 
 /// An observer to rotate an entity when it is dragged
 fn rotate_on_drag(drag: Trigger<Pointer<Drag>>, mut transforms: Query<&mut Transform>) {
-    let mut transform = transforms.get_mut(drag.target()).unwrap();
+    let mut transform = transforms.get_mut(drag.target().unwrap()).unwrap();
     transform.rotate_y(drag.delta.x * 0.02);
     transform.rotate_x(drag.delta.y * 0.02);
 }

examples/picking/simple_picking.rs

@@ -27,13 +27,13 @@ fn setup_scene(
         .observe(on_click_spawn_cube)
         .observe(
             |out: Trigger<Pointer<Out>>, mut texts: Query<&mut TextColor>| {
-                let mut text_color = texts.get_mut(out.target()).unwrap();
+                let mut text_color = texts.get_mut(out.target().unwrap()).unwrap();
                 text_color.0 = Color::WHITE;
             },
         )
         .observe(
             |over: Trigger<Pointer<Over>>, mut texts: Query<&mut TextColor>| {
-                let mut color = texts.get_mut(over.target()).unwrap();
+                let mut color = texts.get_mut(over.target().unwrap()).unwrap();
                 color.0 = bevy::color::palettes::tailwind::CYAN_400.into();
             },
         );
@@ -80,7 +80,7 @@ fn on_click_spawn_cube(
 }
 
 fn on_drag_rotate(drag: Trigger<Pointer<Drag>>, mut transforms: Query<&mut Transform>) {
-    if let Ok(mut transform) = transforms.get_mut(drag.target()) {
+    if let Ok(mut transform) = transforms.get_mut(drag.target().unwrap()) {
         transform.rotate_y(drag.delta.x * 0.02);
         transform.rotate_x(drag.delta.y * 0.02);
     }

examples/picking/sprite_picking.rs

@@ -152,7 +152,7 @@ fn setup_atlas(
 // An observer listener that changes the target entity's color.
 fn recolor_on<E: Debug + Clone + Reflect>(color: Color) -> impl Fn(Trigger<E>, Query<&mut Sprite>) {
     move |ev, mut sprites| {
-        let Ok(mut sprite) = sprites.get_mut(ev.target()) else {
+        let Ok(mut sprite) = sprites.get_mut(ev.target().unwrap()) else {
             return;
         };
         sprite.color = color;

examples/testbed/3d.rs

@@ -281,7 +281,7 @@ mod animation {
         animation: Res<Animation>,
         mut players: Query<(Entity, &mut AnimationPlayer)>,
     ) {
-        for child in children.iter_descendants(trigger.target()) {
+        for child in children.iter_descendants(trigger.target().unwrap()) {
             if let Ok((entity, mut player)) = players.get_mut(child) {
                 let mut transitions = AnimationTransitions::new();
                 transitions

examples/testbed/full_ui.rs

@@ -228,7 +228,13 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                             parent.spawn((
                                 ImageNode::new(asset_server.load("branding/bevy_logo_light.png")),
                                 // Uses the transform to rotate the logo image by 45 degrees
-                                Transform::from_rotation(Quat::from_rotation_z(0.25 * PI)),
+                                Node {
+                                    ..Default::default()
+                                },
+                                UiTransform {
+                                    rotation: Rot2::radians(0.25 * PI),
+                                    ..Default::default()
+                                },
                                 BorderRadius::all(Val::Px(10.)),
                                 Outline {
                                     width: Val::Px(2.),

examples/ui/directional_navigation.rs

@@ -70,7 +70,7 @@ fn universal_button_click_behavior(
     mut trigger: Trigger<Pointer<Click>>,
     mut button_query: Query<(&mut BackgroundColor, &mut ResetTimer)>,
 ) {
-    let button_entity = trigger.target();
+    let button_entity = trigger.target().unwrap();
     if let Ok((mut color, mut reset_timer)) = button_query.get_mut(button_entity) {
         // This would be a great place to play a little sound effect too!
         color.0 = PRESSED_BUTTON.into();

examples/ui/gradients.rs

@@ -26,20 +26,20 @@ fn setup(mut commands: Commands) {
     commands
         .spawn(Node {
             flex_direction: FlexDirection::Column,
-            row_gap: Val::Px(30.),
+            row_gap: Val::Px(20.),
-            margin: UiRect::all(Val::Px(30.)),
+            margin: UiRect::all(Val::Px(20.)),
             ..Default::default()
         })
         .with_children(|commands| {
             for (b, stops) in [
                 (
-                    5.,
+                    4.,
                     vec![
                         ColorStop::new(Color::WHITE, Val::Percent(15.)),
                         ColorStop::new(Color::BLACK, Val::Percent(85.)),
                     ],
                 ),
-                (5., vec![RED.into(), BLUE.into(), LIME.into()]),
+                (4., vec![RED.into(), BLUE.into(), LIME.into()]),
                 (
                     0.,
                     vec![
@@ -64,11 +64,11 @@ fn setup(mut commands: Commands) {
                     commands
                         .spawn(Node {
                             flex_direction: FlexDirection::Column,
-                            row_gap: Val::Px(10.),
+                            row_gap: Val::Px(5.),
                             ..Default::default()
                         })
                         .with_children(|commands| {
-                            for (w, h) in [(100., 100.), (50., 100.), (100., 50.)] {
+                            for (w, h) in [(70., 70.), (35., 70.), (70., 35.)] {
                                 commands
                                     .spawn(Node {
                                         column_gap: Val::Px(10.),
@@ -108,7 +108,7 @@ fn setup(mut commands: Commands) {
                                 aspect_ratio: Some(1.),
                                 height: Val::Percent(100.),
                                 border: UiRect::all(Val::Px(b)),
-                                margin: UiRect::left(Val::Px(30.)),
+                                margin: UiRect::left(Val::Px(20.)),
                                 ..default()
                             },
                             BorderRadius::all(Val::Px(20.)),
@@ -128,7 +128,7 @@ fn setup(mut commands: Commands) {
                                 aspect_ratio: Some(1.),
                                 height: Val::Percent(100.),
                                 border: UiRect::all(Val::Px(b)),
-                                margin: UiRect::left(Val::Px(30.)),
+                                margin: UiRect::left(Val::Px(20.)),
                                 ..default()
                             },
                             BorderRadius::all(Val::Px(20.)),
@@ -148,7 +148,7 @@ fn setup(mut commands: Commands) {
                                 aspect_ratio: Some(1.),
                                 height: Val::Percent(100.),
                                 border: UiRect::all(Val::Px(b)),
-                                margin: UiRect::left(Val::Px(30.)),
+                                margin: UiRect::left(Val::Px(20.)),
                                 ..default()
                             },
                             BorderRadius::all(Val::Px(20.)),

examples/ui/overflow_debug.rs

@@ -4,7 +4,6 @@ use bevy::{input::common_conditions::input_just_pressed, prelude::*, ui::widget:
 use std::f32::consts::{FRAC_PI_2, PI, TAU};
 
 const CONTAINER_SIZE: f32 = 150.0;
-const HALF_CONTAINER_SIZE: f32 = CONTAINER_SIZE / 2.0;
 const LOOP_LENGTH: f32 = 4.0;
 
 fn main() {
@@ -41,16 +40,16 @@ struct AnimationState {
 struct Container(u8);
 
 trait UpdateTransform {
-    fn update(&self, t: f32, transform: &mut Transform);
+    fn update(&self, t: f32, transform: &mut UiTransform);
 }
 
 #[derive(Component)]
 struct Move;
 
 impl UpdateTransform for Move {
-    fn update(&self, t: f32, transform: &mut Transform) {
+    fn update(&self, t: f32, transform: &mut UiTransform) {
-        transform.translation.x = ops::sin(t * TAU - FRAC_PI_2) * HALF_CONTAINER_SIZE;
+        transform.translation.x = Val::Percent(ops::sin(t * TAU - FRAC_PI_2) * 50.);
-        transform.translation.y = -ops::cos(t * TAU - FRAC_PI_2) * HALF_CONTAINER_SIZE;
+        transform.translation.y = Val::Percent(-ops::cos(t * TAU - FRAC_PI_2) * 50.);
     }
 }
 
@@ -58,7 +57,7 @@ impl UpdateTransform for Move {
 struct Scale;
 
 impl UpdateTransform for Scale {
-    fn update(&self, t: f32, transform: &mut Transform) {
+    fn update(&self, t: f32, transform: &mut UiTransform) {
         transform.scale.x = 1.0 + 0.5 * ops::cos(t * TAU).max(0.0);
         transform.scale.y = 1.0 + 0.5 * ops::cos(t * TAU + PI).max(0.0);
     }
@@ -68,9 +67,8 @@ impl UpdateTransform for Scale {
 struct Rotate;
 
 impl UpdateTransform for Rotate {
-    fn update(&self, t: f32, transform: &mut Transform) {
+    fn update(&self, t: f32, transform: &mut UiTransform) {
-        transform.rotation =
+        transform.rotation = Rot2::radians(ops::cos(t * TAU) * 45.0);
-            Quat::from_axis_angle(Vec3::Z, (ops::cos(t * TAU) * 45.0).to_radians());
     }
 }
 
@@ -175,10 +173,6 @@ fn spawn_container(
     update_transform: impl UpdateTransform + Component,
     spawn_children: impl FnOnce(&mut ChildSpawnerCommands),
 ) {
-    let mut transform = Transform::default();
-
-    update_transform.update(0.0, &mut transform);
-
     parent
         .spawn((
             Node {
@@ -198,11 +192,8 @@ fn spawn_container(
                     Node {
                         align_items: AlignItems::Center,
                         justify_content: JustifyContent::Center,
-                        top: Val::Px(transform.translation.x),
-                        left: Val::Px(transform.translation.y),
                         ..default()
                     },
-                    transform,
                     update_transform,
                 ))
                 .with_children(spawn_children);
@@ -233,13 +224,10 @@ fn update_animation(
 
 fn update_transform<T: UpdateTransform + Component>(
     animation: Res<AnimationState>,
-    mut containers: Query<(&mut Transform, &mut Node, &ComputedNode, &T)>,
+    mut containers: Query<(&mut UiTransform, &T)>,
 ) {
-    for (mut transform, mut node, computed_node, update_transform) in &mut containers {
+    for (mut transform, update_transform) in &mut containers {
         update_transform.update(animation.t, &mut transform);
-
-        node.left = Val::Px(transform.translation.x * computed_node.inverse_scale_factor());
-        node.top = Val::Px(transform.translation.y * computed_node.inverse_scale_factor());
     }
 }
 

examples/ui/relative_cursor_position.rs

@@ -78,7 +78,7 @@ fn relative_cursor_position_system(
         "unknown".to_string()
     };
 
-    text_color.0 = if relative_cursor_position.mouse_over() {
+    text_color.0 = if relative_cursor_position.cursor_over() {
         Color::srgb(0.1, 0.9, 0.1)
     } else {
         Color::srgb(0.9, 0.1, 0.1)

examples/ui/scroll.rs

@@ -93,7 +93,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                     mut commands: Commands
                                 | {
                                     if trigger.event().button == PointerButton::Primary {
-                                        commands.entity(trigger.target()).despawn();
+                                        commands.entity(trigger.target().unwrap()).despawn();
                                     }
                                 });
                             }

examples/ui/tab_navigation.rs

@@ -142,7 +142,7 @@ fn setup(mut commands: Commands) {
                                 .observe(
                                     |mut trigger: Trigger<Pointer<Click>>,
                                     mut focus: ResMut<InputFocus>| {
-                                        focus.0 = Some(trigger.target());
+                                        focus.0 = Some(trigger.target().unwrap());
                                         trigger.propagate(false);
                                     },
                                 );

examples/ui/ui_transform.rs

@@ -0,0 +1,302 @@
+//! An example demonstrating how to translate, rotate and scale UI elements.
+use bevy::color::palettes::css::DARK_GRAY;
+use bevy::color::palettes::css::RED;
+use bevy::color::palettes::css::YELLOW;
+use bevy::prelude::*;
+use core::f32::consts::FRAC_PI_8;
+
+fn main() {
+    App::new()
+        .add_plugins(DefaultPlugins)
+        .add_systems(Startup, setup)
+        .add_systems(Update, button_system)
+        .add_systems(Update, translation_system)
+        .run();
+}
+
+const NORMAL_BUTTON: Color = Color::WHITE;
+const HOVERED_BUTTON: Color = Color::Srgba(YELLOW);
+const PRESSED_BUTTON: Color = Color::Srgba(RED);
+
+/// A button that rotates the target node
+#[derive(Component)]
+pub struct RotateButton(pub Rot2);
+
+/// A button that scales the target node
+#[derive(Component)]
+pub struct ScaleButton(pub f32);
+
+/// Marker component so the systems know which entities to translate, rotate and scale
+#[derive(Component)]
+pub struct TargetNode;
+
+/// Handles button interactions
+fn button_system(
+    mut interaction_query: Query<
+        (
+            &Interaction,
+            &mut BackgroundColor,
+            Option<&RotateButton>,
+            Option<&ScaleButton>,
+        ),
+        (Changed<Interaction>, With<Button>),
+    >,
+    mut rotator_query: Query<&mut UiTransform, With<TargetNode>>,
+) {
+    for (interaction, mut color, maybe_rotate, maybe_scale) in &mut interaction_query {
+        match *interaction {
+            Interaction::Pressed => {
+                *color = PRESSED_BUTTON.into();
+                if let Some(step) = maybe_rotate {
+                    for mut transform in rotator_query.iter_mut() {
+                        transform.rotation *= step.0;
+                    }
+                }
+                if let Some(step) = maybe_scale {
+                    for mut transform in rotator_query.iter_mut() {
+                        transform.scale += step.0;
+                        transform.scale =
+                            transform.scale.clamp(Vec2::splat(0.25), Vec2::splat(3.0));
+                    }
+                }
+            }
+            Interaction::Hovered => {
+                *color = HOVERED_BUTTON.into();
+            }
+            Interaction::None => {
+                *color = NORMAL_BUTTON.into();
+            }
+        }
+    }
+}
+
+// move the rotating panel when the arrow keys are pressed
+fn translation_system(
+    time: Res<Time>,
+    input: Res<ButtonInput<KeyCode>>,
+    mut translation_query: Query<&mut UiTransform, With<TargetNode>>,
+) {
+    let controls = [
+        (KeyCode::ArrowLeft, -Vec2::X),
+        (KeyCode::ArrowRight, Vec2::X),
+        (KeyCode::ArrowUp, -Vec2::Y),
+        (KeyCode::ArrowDown, Vec2::Y),
+    ];
+    for &(key_code, direction) in &controls {
+        if input.pressed(key_code) {
+            for mut transform in translation_query.iter_mut() {
+                let d = direction * 50.0 * time.delta_secs();
+                let (Val::Px(x), Val::Px(y)) = (transform.translation.x, transform.translation.y)
+                else {
+                    continue;
+                };
+                let x = (x + d.x).clamp(-150., 150.);
+                let y = (y + d.y).clamp(-150., 150.);
+
+                transform.translation = Val2::px(x, y);
+            }
+        }
+    }
+}
+
+fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
+    // UI camera
+    commands.spawn(Camera2d);
+
+    // Root node filling the whole screen
+    commands.spawn((
+        Node {
+            width: Val::Percent(100.),
+            height: Val::Percent(100.),
+            align_items: AlignItems::Center,
+            justify_content: JustifyContent::Center,
+            ..default()
+        },
+        BackgroundColor(Color::BLACK),
+        children![(
+            Node {
+                align_items: AlignItems::Center,
+                justify_content: JustifyContent::SpaceEvenly,
+                column_gap: Val::Px(25.0),
+                row_gap: Val::Px(25.0),
+                ..default()
+            },
+            BackgroundColor(Color::BLACK),
+            children![
+                (
+                    Node {
+                        flex_direction: FlexDirection::Column,
+                        justify_content: JustifyContent::Center,
+                        row_gap: Val::Px(10.0),
+                        column_gap: Val::Px(10.0),
+                        padding: UiRect::all(Val::Px(10.0)),
+                        ..default()
+                    },
+                    BackgroundColor(Color::BLACK),
+                    GlobalZIndex(1),
+                    children![
+                        (
+                            Button,
+                            Node {
+                                height: Val::Px(50.0),
+                                width: Val::Px(50.0),
+                                align_items: AlignItems::Center,
+                                justify_content: JustifyContent::Center,
+                                ..default()
+                            },
+                            BackgroundColor(Color::WHITE),
+                            RotateButton(Rot2::radians(-FRAC_PI_8)),
+                            children![(Text::new("<--"), TextColor(Color::BLACK),)]
+                        ),
+                        (
+                            Button,
+                            Node {
+                                height: Val::Px(50.0),
+                                width: Val::Px(50.0),
+                                align_items: AlignItems::Center,
+                                justify_content: JustifyContent::Center,
+                                ..default()
+                            },
+                            BackgroundColor(Color::WHITE),
+                            ScaleButton(-0.25),
+                            children![(Text::new("-"), TextColor(Color::BLACK),)]
+                        ),
+                    ]
+                ),
+                // Target node with its own set of buttons
+                (
+                    Node {
+                        flex_direction: FlexDirection::Column,
+                        justify_content: JustifyContent::SpaceBetween,
+                        align_items: AlignItems::Center,
+                        width: Val::Px(300.0),
+                        height: Val::Px(300.0),
+                        ..default()
+                    },
+                    BackgroundColor(DARK_GRAY.into()),
+                    TargetNode,
+                    children![
+                        (
+                            Button,
+                            Node {
+                                width: Val::Px(80.0),
+                                height: Val::Px(80.0),
+                                align_items: AlignItems::Center,
+                                justify_content: JustifyContent::Center,
+                                ..default()
+                            },
+                            BackgroundColor(Color::WHITE),
+                            children![(Text::new("Top"), TextColor(Color::BLACK))]
+                        ),
+                        (
+                            Node {
+                                align_self: AlignSelf::Stretch,
+                                justify_content: JustifyContent::SpaceBetween,
+                                align_items: AlignItems::Center,
+                                ..default()
+                            },
+                            children![
+                                (
+                                    Button,
+                                    Node {
+                                        width: Val::Px(80.0),
+                                        height: Val::Px(80.0),
+                                        align_items: AlignItems::Center,
+                                        justify_content: JustifyContent::Center,
+                                        ..default()
+                                    },
+                                    BackgroundColor(Color::WHITE),
+                                    UiTransform::from_rotation(Rot2::radians(
+                                        -std::f32::consts::FRAC_PI_2
+                                    )),
+                                    children![(Text::new("Left"), TextColor(Color::BLACK),)]
+                                ),
+                                (
+                                    Node {
+                                        width: Val::Px(100.),
+                                        height: Val::Px(100.),
+                                        ..Default::default()
+                                    },
+                                    ImageNode {
+                                        image: asset_server.load("branding/icon.png"),
+                                        image_mode: NodeImageMode::Stretch,
+                                        ..default()
+                                    }
+                                ),
+                                (
+                                    Button,
+                                    Node {
+                                        width: Val::Px(80.0),
+                                        height: Val::Px(80.0),
+                                        align_items: AlignItems::Center,
+                                        justify_content: JustifyContent::Center,
+                                        ..default()
+                                    },
+                                    UiTransform::from_rotation(Rot2::radians(
+                                        core::f32::consts::FRAC_PI_2
+                                    )),
+                                    BackgroundColor(Color::WHITE),
+                                    children![(Text::new("Right"), TextColor(Color::BLACK))]
+                                ),
+                            ]
+                        ),
+                        (
+                            Button,
+                            Node {
+                                width: Val::Px(80.0),
+                                height: Val::Px(80.0),
+                                align_items: AlignItems::Center,
+                                justify_content: JustifyContent::Center,
+                                ..default()
+                            },
+                            BackgroundColor(Color::WHITE),
+                            UiTransform::from_rotation(Rot2::radians(std::f32::consts::PI)),
+                            children![(Text::new("Bottom"), TextColor(Color::BLACK),)]
+                        ),
+                    ]
+                ),
+                // Right column of controls
+                (
+                    Node {
+                        flex_direction: FlexDirection::Column,
+                        justify_content: JustifyContent::Center,
+                        row_gap: Val::Px(10.0),
+                        column_gap: Val::Px(10.0),
+                        padding: UiRect::all(Val::Px(10.0)),
+                        ..default()
+                    },
+                    BackgroundColor(Color::BLACK),
+                    GlobalZIndex(1),
+                    children![
+                        (
+                            Button,
+                            Node {
+                                height: Val::Px(50.0),
+                                width: Val::Px(50.0),
+                                align_items: AlignItems::Center,
+                                justify_content: JustifyContent::Center,
+                                ..default()
+                            },
+                            BackgroundColor(Color::WHITE),
+                            RotateButton(Rot2::radians(FRAC_PI_8)),
+                            children![(Text::new("-->"), TextColor(Color::BLACK),)]
+                        ),
+                        (
+                            Button,
+                            Node {
+                                height: Val::Px(50.0),
+                                width: Val::Px(50.0),
+                                align_items: AlignItems::Center,
+                                justify_content: JustifyContent::Center,
+                                ..default()
+                            },
+                            BackgroundColor(Color::WHITE),
+                            ScaleButton(0.25),
+                            children![(Text::new("+"), TextColor(Color::BLACK),)]
+                        ),
+                    ]
+                )
+            ]
+        )],
+    ));
+}

examples/ui/viewport_node.rs

@@ -91,7 +91,7 @@ fn test(
 
 fn on_drag_viewport(drag: Trigger<Pointer<Drag>>, mut node_query: Query<&mut Node>) {
     if matches!(drag.button, PointerButton::Secondary) {
-        let mut node = node_query.get_mut(drag.target()).unwrap();
+        let mut node = node_query.get_mut(drag.target().unwrap()).unwrap();
 
         if let (Val::Px(top), Val::Px(left)) = (node.top, node.left) {
             node.left = Val::Px(left + drag.delta.x);
@@ -102,7 +102,7 @@ fn on_drag_viewport(drag: Trigger<Pointer<Drag>>, mut node_query: Query<&mut Nod
 
 fn on_drag_cuboid(drag: Trigger<Pointer<Drag>>, mut transform_query: Query<&mut Transform>) {
     if matches!(drag.button, PointerButton::Primary) {
-        let mut transform = transform_query.get_mut(drag.target()).unwrap();
+        let mut transform = transform_query.get_mut(drag.target().unwrap()).unwrap();
         transform.rotate_y(drag.delta.x * 0.02);
         transform.rotate_x(drag.delta.y * 0.02);
     }

release-content/migration-guides/observer_triggers.md

@@ -0,0 +1,12 @@
+---
+title: Observer Triggers
+pull_requests: [19440]
+---
+
+Observers may be triggered on particular entities or globally.
+Previously, a global trigger would claim to trigger on a particular `Entity`, `Entity::PLACEHOLDER`.
+For correctness and transparency, triggers have been changed to `Option<Entity>`.
+
+`Trigger::target` now returns `Option<Entity>` and `ObserverTrigger::target` is now of type `Option<Entity>`.
+If you were checking for `Entity::PLACEHOLDER`, migrate to handling the `None` case.
+If you were not checking for `Entity::PLACEHOLDER`, migrate to unwrapping, as `Entity::PLACEHOLDER` would have caused a panic before, at a later point.

release-content/migration-guides/relative_cursor_position_is_object_centered.md

@@ -0,0 +1,6 @@
+---
+title: RelativeCursorPosition is object-centered
+pull_requests: [16615]
+---
+
+`RelativeCursorPosition`'s coordinates are now object-centered with (0,0) at the the center of the node and the corners at (±0.5, ±0.5). Its `normalized_visible_node_rect` field has been removed and replaced with a new `cursor_over: bool` field which is set to true when the cursor is hovering a visible section of the UI node.

release-content/migration-guides/specialized_ui_transform.md

@@ -0,0 +1,32 @@
+---
+title: Specialized UI transform
+pull_requests: [16615]
+---
+
+Bevy UI now uses specialized 2D UI transform components `UiTransform` and `UiGlobalTransform` in place of `Transform` and `GlobalTransform`.
+
+UiTransform is a 2d-only equivalent of Transform with a responsive translation in `Val`s. `UiGlobalTransform` newtypes `Affine2` and is updated in `ui_layout_system
+
+`Node` now requires `UiTransform` instead of `Transform`. `UiTransform` requires `UiGlobalTransform`.
+
+The `UiTransform` equivalent of the `Transform`:
+
+```rust
+Transform {
+    translation: Vec3 { x, y, z },
+    rotation:Quat::from_rotation_z(radians),
+    scale,
+}
+```
+
+is
+
+```rust
+UiTransform {
+    translation: Val2::px(x, y),
+    rotation: Rot2::from_rotation(radians),
+    scale: scale.xy(),
+} 
+```
+
+In previous versions of Bevy `ui_layout_system` would overwrite UI node's `Transform::translation` each frame. `UiTransform`s aren't overwritten and there is no longer any need for systems that cache and rewrite the transform for translated UI elements.

release-content/migration-guides/unified_system_state_flag.md

@@ -0,0 +1,43 @@
+---
+title: Unified system state flag
+pull_requests: [19506]
+---
+
+Now the system have a unified `SystemStateFlags` to represent its different states.
+
+If your code previously looked like this:
+
+```rust
+impl System for MyCustomSystem {
+    // ...
+
+    fn is_send(&self) -> bool {
+        false
+    }
+
+    fn is_exclusive(&self) -> bool {
+        true
+    }
+
+    fn has_deferred(&self) -> bool {
+        false
+    }
+
+    // ....
+}
+```
+
+You should migrate it to:
+
+```rust
+impl System for MyCustomSystem{
+  // ...
+
+  fn flags(&self) -> SystemStateFlags {
+    // non-send , exclusive , no deferred
+    SystemStateFlags::NON_SEND | SystemStateFlags::EXCLUSIVE
+  }
+
+  // ...
+}
+```

release-content/release-notes/specialized_ui_transform.md

@@ -0,0 +1,7 @@
+---
+title: Specialized UI Transform
+authors: ["@Ickshonpe"]
+pull_requests: [16615]
+---
+
+In Bevy UI `Transform` and `GlobalTransform` have been replaced by `UiTransform` and `UiGlobalTransform`.  `UiTransform` is a specialized 2D UI transform which supports responsive translations.