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`.
53 lines
1.5 KiB
Rust
53 lines
1.5 KiB
Rust
//! This example illustrates how to react to component change.
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use bevy::prelude::*;
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use rand::Rng;
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fn main() {
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App::new()
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.add_plugins(DefaultPlugins)
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.add_startup_system(setup)
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.add_system(change_component)
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.add_system(change_detection)
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.add_system(tracker_monitoring)
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.run();
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}
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#[derive(Component, Debug)]
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struct MyComponent(f64);
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fn setup(mut commands: Commands) {
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commands.spawn_bundle(MyComponent(0.));
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commands.spawn_bundle(Transform::IDENTITY);
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}
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fn change_component(time: Res<Time>, mut query: Query<(Entity, &mut MyComponent)>) {
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for (entity, mut component) in &mut query {
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if rand::thread_rng().gen_bool(0.1) {
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info!("changing component {:?}", entity);
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component.0 = time.seconds_since_startup();
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}
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}
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}
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// There are query filters for `Changed<T>` and `Added<T>`
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// Only entities matching the filters will be in the query
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fn change_detection(query: Query<(Entity, &MyComponent), Changed<MyComponent>>) {
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for (entity, component) in &query {
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info!("{:?} changed: {:?}", entity, component,);
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}
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}
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// By looking at trackers, the query is not filtered but the information is available
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fn tracker_monitoring(
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query: Query<(
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Entity,
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Option<&MyComponent>,
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Option<ChangeTrackers<MyComponent>>,
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)>,
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) {
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for (entity, component, trackers) in &query {
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info!("{:?}: {:?} -> {:?}", entity, component, trackers);
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}
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}
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