Use hooks and observers for component initialization

src/collision/collider/backend.rs

@@ -91,6 +91,9 @@ impl<C: ScalableCollider> Plugin for ColliderBackendPlugin<C> {
  app.insert_resource(ColliderRemovalSystem(collider_removed_id));
  }
 
+ // Initialize missing components for colliders.
+ app.observe(on_add_collider::<C>);
+
  // Register a component hook that updates mass properties of rigid bodies
  // when the colliders attached to them are removed.
  // Also removes `ColliderMarker` components.
@@ -197,7 +200,6 @@ impl<C: ScalableCollider> Plugin for ColliderBackendPlugin<C> {
  app.add_systems(
  self.schedule,
  (
- init_colliders::<C>.in_set(PrepareSet::InitColliders),
  init_transforms::<C>
  .in_set(PrepareSet::InitTransforms)
  .after(init_transforms::<RigidBody>),
@@ -214,9 +216,7 @@ impl<C: ScalableCollider> Plugin for ColliderBackendPlugin<C> {
  // Update collider parents for colliders that are on the same entity as the rigid body.
  app.add_systems(
  self.schedule,
- update_root_collider_parents::<C>
- .after(PrepareSet::InitColliders)
- .before(PrepareSet::Finalize),
+ update_root_collider_parents::<C>.before(PrepareSet::Finalize),
  );
 
  let physics_schedule = app
@@ -251,12 +251,11 @@ impl<C: ScalableCollider> Plugin for ColliderBackendPlugin<C> {
 pub struct ColliderMarker;
 
 /// Initializes missing components for [colliders](Collider).
-#[allow(clippy::type_complexity)]
-pub(crate) fn init_colliders<C: AnyCollider>(
+pub(crate) fn on_add_collider<C: AnyCollider>(
+ trigger: Trigger<OnAdd, C>,
  mut commands: Commands,
- mut colliders: Query<
+ colliders: Query<
  (
- Entity,
  &C,
  Option<&ColliderAabb>,
  Option<&ColliderDensity>,
@@ -265,28 +264,29 @@ pub(crate) fn init_colliders<C: AnyCollider>(
  Added<C>,
  >,
 ) {
- for (entity, collider, aabb, density, is_sensor) in &mut colliders {
- let density = *density.unwrap_or(&ColliderDensity::default());
- let mass_properties = if is_sensor {
- ColliderMassProperties::ZERO
- } else {
- collider.mass_properties(density.0)
- };
-
- commands.entity(entity).try_insert((
- *aabb.unwrap_or(&collider.aabb(Vector::ZERO, Rotation::default())),
- density,
- mass_properties,
- CollidingEntities::default(),
- ColliderMarker,
- ));
- }
+ let Ok((collider, aabb, density, is_sensor)) = colliders.get(trigger.entity()) else {
+ return;
+ };
+
+ let density = *density.unwrap_or(&ColliderDensity::default());
+ let mass_properties = if is_sensor {
+ ColliderMassProperties::ZERO
+ } else {
+ collider.mass_properties(density.0)
+ };
+
+ commands.entity(trigger.entity()).try_insert((
+ *aabb.unwrap_or(&collider.aabb(Vector::ZERO, Rotation::default())),
+ density,
+ mass_properties,
+ CollidingEntities::default(),
+ ColliderMarker,
+ ));
 }
 
 /// Updates [`ColliderParent`] for colliders that are on the same entity as the [`RigidBody`].
 ///
 /// The [`ColliderHierarchyPlugin`] should be used to handle hierarchies.
-#[allow(clippy::type_complexity)]
 fn update_root_collider_parents<C: AnyCollider>(
  mut commands: Commands,
  mut bodies: Query<

src/collision/collider/hierarchy.rs

@@ -58,17 +58,13 @@ impl Plugin for ColliderHierarchyPlugin {
 
  app.configure_sets(
  self.schedule,
- MarkColliderAncestors
- .after(PrepareSet::InitColliders)
- .before(PrepareSet::PropagateTransforms),
+ MarkColliderAncestors.before(PrepareSet::PropagateTransforms),
  );
 
  // Update collider parents.
  app.add_systems(
  self.schedule,
- update_collider_parents
- .after(PrepareSet::InitColliders)
- .before(PrepareSet::Finalize),
+ update_collider_parents.before(PrepareSet::Finalize),
  );
 
  // Run transform propagation if new colliders without rigid bodies have been added.

src/dynamics/ccd/mod.rs

@@ -226,11 +226,11 @@
 //! Finally, making the [physics timestep](Physics) smaller can also help.
 //! However, this comes at the cost of worse performance for the entire simulation.
 
-use crate::{collision::broad_phase::AabbIntersections, prelude::*, prepare::PrepareSet};
+use crate::{collision::broad_phase::AabbIntersections, prelude::*};
 #[cfg(any(feature = "parry-f32", feature = "parry-f64"))]
 use bevy::ecs::query::QueryData;
 use bevy::{
- ecs::{intern::Interned, schedule::ScheduleLabel},
+ ecs::component::{ComponentHooks, StorageType},
  prelude::*,
 };
 use derive_more::From;
@@ -240,36 +240,12 @@ use parry::query::{
 };
 
 /// A plugin for [Continuous Collision Detection](self).
-pub struct CcdPlugin {
- schedule: Interned<dyn ScheduleLabel>,
-}
-
-impl CcdPlugin {
- /// Creates a [`CcdPlugin`] with the schedule that is used for running the [`PhysicsSchedule`].
- ///
- /// The default schedule is `PostUpdate`.
- pub fn new(schedule: impl ScheduleLabel) -> Self {
- Self {
- schedule: schedule.intern(),
- }
- }
-}
-
-impl Default for CcdPlugin {
- fn default() -> Self {
- Self::new(PostUpdate)
- }
-}
+pub struct CcdPlugin;
 
 impl Plugin for CcdPlugin {
  fn build(&self, app: &mut App) {
  app.register_type::<SweptCcd>().register_type::<SweepMode>();
 
- app.add_systems(
- self.schedule,
- init_ccd_aabb_intersections.in_set(PrepareSet::InitColliders),
- );
-
  // Get the `PhysicsSchedule`, and panic if it doesn't exist.
  let physics = app
  .get_schedule_mut(PhysicsSchedule)
@@ -397,7 +373,7 @@ impl SpeculativeMargin {
 /// ));
 /// }
 /// ```
-#[derive(Component, Clone, Copy, Debug, PartialEq, Reflect)]
+#[derive(Clone, Copy, Debug, PartialEq, Reflect)]
 #[reflect(Component)]
 pub struct SweptCcd {
  /// The type of sweep used for swept CCD.
@@ -481,6 +457,19 @@ impl SweptCcd {
  }
 }
 
+impl Component for SweptCcd {
+ const STORAGE_TYPE: StorageType = StorageType::Table;
+
+ fn register_component_hooks(hooks: &mut ComponentHooks) {
+ hooks.on_add(|mut world, entity, _| {
+ world
+ .commands()
+ .entity(entity)
+ .insert(AabbIntersections::default());
+ });
+ }
+}
+
 /// The algorithm used for [Swept Continuous Collision Detection](self#swept-ccd).
 ///
 /// If two entities with different sweep modes collide, [`SweepMode::NonLinear`]
@@ -510,12 +499,6 @@ pub enum SweepMode {
  NonLinear,
 }
 
-fn init_ccd_aabb_intersections(mut commands: Commands, query: Query<Entity, Added<SweptCcd>>) {
- for entity in &query {
- commands.entity(entity).insert(AabbIntersections::default());
- }
-}
-
 #[cfg(any(feature = "parry-f32", feature = "parry-f64"))]
 #[derive(QueryData)]
 #[query_data(mutable)]

src/lib.rs

@@ -735,9 +735,9 @@ impl PluginGroup for PhysicsPlugins {
  .add(ContactReportingPlugin)
  .add(IntegratorPlugin::default())
  .add(SolverPlugin::new_with_length_unit(self.length_unit))
- .add(CcdPlugin::new(self.schedule))
+ .add(CcdPlugin)
  .add(SleepingPlugin)
- .add(SpatialQueryPlugin::new(self.schedule))
+ .add(SpatialQueryPlugin)
  .add(SyncPlugin::new(self.schedule))
  }
 }