cd15f0f5be
# Objective Take advantage of the "impl Bundle for Component" changes in #2975 / add the follow up changes discussed there. ## Solution - Change `insert` and `remove` to accept a Bundle instead of a Component (for both Commands and World) - Deprecate `insert_bundle`, `remove_bundle`, and `remove_bundle_intersection` - Add `remove_intersection` --- ## Changelog - Change `insert` and `remove` now accept a Bundle instead of a Component (for both Commands and World) - `insert_bundle` and `remove_bundle` are deprecated ## Migration Guide Replace `insert_bundle` with `insert`: ```rust // Old (0.8) commands.spawn().insert_bundle(SomeBundle::default()); // New (0.9) commands.spawn().insert(SomeBundle::default()); ``` Replace `remove_bundle` with `remove`: ```rust // Old (0.8) commands.entity(some_entity).remove_bundle::<SomeBundle>(); // New (0.9) commands.entity(some_entity).remove::<SomeBundle>(); ``` Replace `remove_bundle_intersection` with `remove_intersection`: ```rust // Old (0.8) world.entity_mut(some_entity).remove_bundle_intersection::<SomeBundle>(); // New (0.9) world.entity_mut(some_entity).remove_intersection::<SomeBundle>(); ``` Consider consolidating as many operations as possible to improve ergonomics and cut down on archetype moves: ```rust // Old (0.8) commands.spawn() .insert_bundle(SomeBundle::default()) .insert(SomeComponent); // New (0.9) - Option 1 commands.spawn().insert(( SomeBundle::default(), SomeComponent, )) // New (0.9) - Option 2 commands.spawn_bundle(( SomeBundle::default(), SomeComponent, )) ``` ## Next Steps Consider changing `spawn` to accept a bundle and deprecate `spawn_bundle`.
48 lines
1.2 KiB
Rust
48 lines
1.2 KiB
Rust
//! This example creates a custom [`SystemParam`] struct that counts the number of players.
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use bevy::{ecs::system::SystemParam, prelude::*};
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fn main() {
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App::new()
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.insert_resource(PlayerCount(0))
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.add_startup_system(spawn)
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.add_system(count_players)
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.run();
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}
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#[derive(Component)]
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pub struct Player;
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#[derive(Resource)]
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pub struct PlayerCount(usize);
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/// The [`SystemParam`] struct can contain any types that can also be included in a
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/// system function signature.
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///
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/// In this example, it includes a query and a mutable resource.
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#[derive(SystemParam)]
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struct PlayerCounter<'w, 's> {
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players: Query<'w, 's, &'static Player>,
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count: ResMut<'w, PlayerCount>,
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}
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impl<'w, 's> PlayerCounter<'w, 's> {
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fn count(&mut self) {
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self.count.0 = self.players.iter().len();
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}
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}
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/// Spawn some players to count
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fn spawn(mut commands: Commands) {
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commands.spawn_bundle(Player);
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commands.spawn_bundle(Player);
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commands.spawn_bundle(Player);
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}
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/// The [`SystemParam`] can be used directly in a system argument.
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fn count_players(mut counter: PlayerCounter) {
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counter.count();
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println!("{} players in the game", counter.count.0);
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}
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