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		dcc03724a5
		
	
	
	
	
		
			
			# Objective NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267. "Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365). ## Solution This adds "base sets" as a variant of `SystemSet`: A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive: ```rust #[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)] #[system_set(base)] enum MyBaseSet { A, B, } ``` **Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build. **Base sets cannot belong to other sets**: this is where the word "base" comes from Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set. ```rust app.add_system(foo.in_base_set(MyBaseSet::A)) // X must be a normal set ... base sets cannot be added to base sets .configure_set(X.in_base_set(MyBaseSet::A)) ``` Base sets can still be configured like normal sets: ```rust app.add_system(MyBaseSet::B.after(MyBaseSet::Ap)) ``` The primary use case for base sets is enabling a "default base set": ```rust schedule.set_default_base_set(CoreSet::Update) // this will belong to CoreSet::Update by default .add_system(foo) // this will override the default base set with PostUpdate .add_system(bar.in_base_set(CoreSet::PostUpdate)) ``` This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides. --- ## Changelog - Added "base sets" and ported CoreSet to use them. ## Migration Guide TODO
		
			
				
	
	
		
			66 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! Update a scene from a glTF file, either by spawning the scene as a child of another entity,
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| //! or by accessing the entities of the scene.
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| 
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| use bevy::prelude::*;
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| 
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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(move_scene_entities)
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|         .run();
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| }
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| 
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| #[derive(Component)]
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| struct MovedScene;
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| 
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| fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
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|     commands.spawn(PointLightBundle {
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|         transform: Transform::from_xyz(4.0, 5.0, 4.0),
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|         ..default()
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|     });
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|     commands.spawn(Camera3dBundle {
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|         transform: Transform::from_xyz(1.05, 0.9, 1.5)
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|             .looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y),
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|         ..default()
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|     });
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| 
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|     // Spawn the scene as a child of this entity at the given transform
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|     commands.spawn(SceneBundle {
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|         transform: Transform::from_xyz(0.0, 0.0, -1.0),
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|         scene: asset_server.load("models/FlightHelmet/FlightHelmet.gltf#Scene0"),
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|         ..default()
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|     });
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| 
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|     // Spawn a second scene, and add a tag component to be able to target it later
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|     commands.spawn((
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|         SceneBundle {
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|             scene: asset_server.load("models/FlightHelmet/FlightHelmet.gltf#Scene0"),
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|             ..default()
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|         },
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|         MovedScene,
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|     ));
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| }
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| 
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| // This system will move all entities that are descendants of MovedScene (which will be all entities spawned in the scene)
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| fn move_scene_entities(
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|     time: Res<Time>,
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|     moved_scene: Query<Entity, With<MovedScene>>,
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|     children: Query<&Children>,
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|     mut transforms: Query<&mut Transform>,
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| ) {
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|     for moved_scene_entity in &moved_scene {
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|         let mut offset = 0.;
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|         for entity in children.iter_descendants(moved_scene_entity) {
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|             if let Ok(mut transform) = transforms.get_mut(entity) {
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|                 transform.translation = Vec3::new(
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|                     offset * time.elapsed_seconds().sin() / 20.,
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|                     0.,
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|                     time.elapsed_seconds().cos() / 20.,
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|                 );
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|                 offset += 1.0;
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|             }
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|         }
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|     }
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| }
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