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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
		
			
				
	
	
		
			81 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! Showcases the `RelativeCursorPosition` component, used to check the position of the cursor relative to a UI node.
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| 
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| use bevy::{prelude::*, ui::RelativeCursorPosition, winit::WinitSettings};
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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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|         // Only run the app when there is user input. This will significantly reduce CPU/GPU use.
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|         .insert_resource(WinitSettings::desktop_app())
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|         .add_startup_system(setup)
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|         .add_system(relative_cursor_position_system)
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|         .run();
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| }
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| 
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| fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
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|     commands.spawn(Camera2dBundle::default());
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| 
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|     commands
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|         .spawn(NodeBundle {
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|             style: Style {
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|                 size: Size::new(Val::Percent(100.0), Val::Percent(100.0)),
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|                 align_items: AlignItems::Center,
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|                 justify_content: JustifyContent::Center,
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|                 flex_direction: FlexDirection::Column,
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|                 ..default()
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|             },
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|             ..default()
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|         })
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|         .with_children(|parent| {
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|             parent
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|                 .spawn(NodeBundle {
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|                     style: Style {
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|                         size: Size::new(Val::Px(250.0), Val::Px(250.0)),
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|                         margin: UiRect::new(Val::Px(0.), Val::Px(0.), Val::Px(0.), Val::Px(15.)),
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|                         ..default()
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|                     },
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|                     background_color: Color::rgb(235., 35., 12.).into(),
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|                     ..default()
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|                 })
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|                 .insert(RelativeCursorPosition::default());
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| 
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|             parent.spawn(TextBundle {
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|                 text: Text::from_section(
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|                     "(0.0, 0.0)",
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|                     TextStyle {
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|                         font: asset_server.load("fonts/FiraSans-Bold.ttf"),
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|                         font_size: 40.0,
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|                         color: Color::rgb(0.9, 0.9, 0.9),
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|                     },
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|                 ),
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|                 ..default()
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|             });
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|         });
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| }
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| 
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| /// This systems polls the relative cursor position and displays its value in a text component.
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| fn relative_cursor_position_system(
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|     relative_cursor_position_query: Query<&RelativeCursorPosition>,
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|     mut output_query: Query<&mut Text>,
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| ) {
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|     let relative_cursor_position = relative_cursor_position_query.single();
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| 
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|     let mut output = output_query.single_mut();
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| 
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|     output.sections[0].value =
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|         if let Some(relative_cursor_position) = relative_cursor_position.normalized {
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|             format!(
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|                 "({:.1}, {:.1})",
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|                 relative_cursor_position.x, relative_cursor_position.y
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|             )
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|         } else {
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|             "unknown".to_string()
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|         };
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| 
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|     output.sections[0].style.color = if relative_cursor_position.mouse_over() {
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|         Color::rgb(0.1, 0.9, 0.1)
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|     } else {
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|         Color::rgb(0.9, 0.1, 0.1)
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|     };
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| }
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