Components as entities

benches/benches/bevy_ecs/empty_archetypes.rs

@@ -166,7 +166,6 @@ fn empty_archetypes(criterion: &mut Criterion) {
             schedule.add_systems(iter);
         });
         add_archetypes(&mut world, archetype_count);
-        world.clear_entities();
         let mut e = world.spawn_empty();
         e.insert(A::<0>(1.0));
         e.insert(A::<1>(1.0));
@@ -197,7 +196,6 @@ fn empty_archetypes(criterion: &mut Criterion) {
             schedule.add_systems(for_each);
         });
         add_archetypes(&mut world, archetype_count);
-        world.clear_entities();
         let mut e = world.spawn_empty();
         e.insert(A::<0>(1.0));
         e.insert(A::<1>(1.0));
@@ -228,7 +226,6 @@ fn empty_archetypes(criterion: &mut Criterion) {
             schedule.add_systems(par_for_each);
         });
         add_archetypes(&mut world, archetype_count);
-        world.clear_entities();
         let mut e = world.spawn_empty();
         e.insert(A::<0>(1.0));
         e.insert(A::<1>(1.0));

benches/benches/bevy_ecs/main.rs

@@ -15,13 +15,15 @@ mod fragmentation;
 mod iteration;
 mod observers;
 mod param;
+mod resources;
 mod scheduling;
 mod world;
 
 criterion_main!(
     bundles::benches,
     change_detection::benches,
     components::benches,
+    resources::benches,
     empty_archetypes::benches,
     entity_cloning::benches,
     events::benches,

benches/benches/bevy_ecs/resources.rs

@@ -0,0 +1,69 @@
+use std::{alloc::Layout, hint::black_box, ptr::NonNull};
+
+use benches::bench;
+use bevy_ecs::{
+    change_detection::MaybeLocation,
+    component::{ComponentCloneBehavior, ComponentDescriptor, StorageType},
+    prelude::*,
+    ptr::OwningPtr,
+};
+use criterion::{criterion_group, Criterion};
+
+criterion_group!(benches, get, get_mut, insert_remove);
+
+fn create_world() -> World {
+    let mut world = World::new();
+    for _ in 0..500 {
+        // SAFETY: Uses zero-sized value, never drops
+        unsafe {
+            let resource_id =
+                world.register_component_with_descriptor(ComponentDescriptor::new_with_layout(
+                    "",
+                    StorageType::SparseSet,
+                    Layout::new::<()>(),
+                    None,
+                    true,
+                    ComponentCloneBehavior::Default,
+                    None,
+                ));
+            world.insert_resource_by_id(
+                resource_id,
+                OwningPtr::new(NonNull::dangling()),
+                MaybeLocation::caller(),
+            );
+        }
+    }
+    world
+}
+
+#[derive(Resource)]
+struct R;
+
+pub fn get(criterion: &mut Criterion) {
+    let mut world = create_world();
+    world.insert_resource(R);
+    criterion.bench_function(bench!("get"), |bencher| {
+        bencher.iter(|| world.get_resource::<R>());
+    });
+}
+
+pub fn get_mut(criterion: &mut Criterion) {
+    let mut world = create_world();
+    world.insert_resource(R);
+    criterion.bench_function(bench!("get_mut"), |bencher| {
+        bencher.iter(|| {
+            black_box(world.get_resource_mut::<R>());
+        });
+    });
+}
+
+pub fn insert_remove(criterion: &mut Criterion) {
+    let mut world = create_world();
+    criterion.bench_function(bench!("insert_remove"), |bencher| {
+        bencher.iter(|| {
+            world.insert_resource(R);
+            black_box(&mut world);
+            world.remove_resource::<R>()
+        });
+    });
+}

crates/bevy_ecs/macros/src/component.rs

@@ -47,7 +47,7 @@ pub fn derive_resource(input: TokenStream) -> TokenStream {
         }
     });
 
-    let storage = storage_path(&bevy_ecs_path, StorageTy::Table);
+    let storage = storage_path(&bevy_ecs_path, StorageTy::SparseSet);
 
     let on_add_path = None;
     let on_remove_path = None;

crates/bevy_ecs/src/component/constants.rs

@@ -1,14 +1,14 @@
 //! Constant components included in every world.
 
-/// `usize` for the [`Add`](crate::lifecycle::Add) component used in lifecycle observers.
-pub const ADD: usize = 0;
-/// `usize` for the [`Insert`](crate::lifecycle::Insert) component used in lifecycle observers.
-pub const INSERT: usize = 1;
-/// `usize` for the [`Discard`](crate::lifecycle::Discard) component used in lifecycle observers.
-pub const DISCARD: usize = 2;
-/// `usize` for the [`Remove`](crate::lifecycle::Remove) component used in lifecycle observers.
-pub const REMOVE: usize = 3;
-/// `usize` for [`Despawn`](crate::lifecycle::Despawn) component used in lifecycle observers.
-pub const DESPAWN: usize = 4;
-/// `usize` of the [`IsResource`](crate::resource::IsResource) component used to mark entities with resources.
-pub const IS_RESOURCE: usize = 5;
+/// `u32` for the [`Add`](crate::lifecycle::Add) component used in lifecycle observers.
+pub const ADD: u32 = 0;
+/// `u32` for the [`Insert`](crate::lifecycle::Insert) component used in lifecycle observers.
+pub const INSERT: u32 = 1;
+/// `u32` for the [`Discard`](crate::lifecycle::Discard) component used in lifecycle observers.
+pub const DISCARD: u32 = 2;
+/// `u32` for the [`Remove`](crate::lifecycle::Remove) component used in lifecycle observers.
+pub const REMOVE: u32 = 3;
+/// `u32` for [`Despawn`](crate::lifecycle::Despawn) component used in lifecycle observers.
+pub const DESPAWN: u32 = 4;
+/// `u32` of the [`IsResource`](crate::resource::IsResource) component used to mark entities with resources.
+pub const IS_RESOURCE: u32 = 5;