 015f2c69ca
			
		
	
	
		015f2c69ca
		
			
		
	
	
	
	
		
			
			# Objective Continue improving the user experience of our UI Node API in the direction specified by [Bevy's Next Generation Scene / UI System](https://github.com/bevyengine/bevy/discussions/14437) ## Solution As specified in the document above, merge `Style` fields into `Node`, and move "computed Node fields" into `ComputedNode` (I chose this name over something like `ComputedNodeLayout` because it currently contains more than just layout info. If we want to break this up / rename these concepts, lets do that in a separate PR). `Style` has been removed. This accomplishes a number of goals: ## Ergonomics wins Specifying both `Node` and `Style` is now no longer required for non-default styles Before: ```rust commands.spawn(( Node::default(), Style { width: Val::Px(100.), ..default() }, )); ``` After: ```rust commands.spawn(Node { width: Val::Px(100.), ..default() }); ``` ## Conceptual clarity `Style` was never a comprehensive "style sheet". It only defined "core" style properties that all `Nodes` shared. Any "styled property" that couldn't fit that mold had to be in a separate component. A "real" style system would style properties _across_ components (`Node`, `Button`, etc). We have plans to build a true style system (see the doc linked above). By moving the `Style` fields to `Node`, we fully embrace `Node` as the driving concept and remove the "style system" confusion. ## Next Steps * Consider identifying and splitting out "style properties that aren't core to Node". This should not happen for Bevy 0.15. --- ## Migration Guide Move any fields set on `Style` into `Node` and replace all `Style` component usage with `Node`. Before: ```rust commands.spawn(( Node::default(), Style { width: Val::Px(100.), ..default() }, )); ``` After: ```rust commands.spawn(Node { width: Val::Px(100.), ..default() }); ``` For any usage of the "computed node properties" that used to live on `Node`, use `ComputedNode` instead: Before: ```rust fn system(nodes: Query<&Node>) { for node in &nodes { let computed_size = node.size(); } } ``` After: ```rust fn system(computed_nodes: Query<&ComputedNode>) { for computed_node in &computed_nodes { let computed_size = computed_node.size(); } } ```
		
			
				
	
	
		
			76 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! A simple scene to demonstrate picking events
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| 
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| use bevy::{color::palettes::tailwind::CYAN_400, prelude::*};
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| 
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| fn main() {
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|     let mut app = App::new();
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|     app.add_plugins(DefaultPlugins);
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| 
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|     app.add_systems(Startup, setup);
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| 
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|     app.run();
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| }
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| 
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| /// set up a simple 3D scene
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| fn setup(
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|     mut commands: Commands,
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|     mut meshes: ResMut<Assets<Mesh>>,
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|     mut materials: ResMut<Assets<StandardMaterial>>,
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| ) {
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|     commands
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|         .spawn((
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|             Text::new("Click Me to get a box"),
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|             Node {
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|                 position_type: PositionType::Absolute,
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|                 top: Val::Percent(12.0),
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|                 left: Val::Percent(12.0),
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|                 ..default()
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|             },
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|         ))
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|         .observe(
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|             |_click: Trigger<Pointer<Click>>,
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|              mut commands: Commands,
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|              mut meshes: ResMut<Assets<Mesh>>,
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|              mut materials: ResMut<Assets<StandardMaterial>>,
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|              mut num: Local<usize>| {
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|                 commands.spawn((
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|                     Mesh3d(meshes.add(Cuboid::new(1.0, 1.0, 1.0))),
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|                     MeshMaterial3d(materials.add(Color::srgb_u8(124, 144, 255))),
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|                     Transform::from_xyz(0.0, 0.5 + 1.1 * *num as f32, 0.0),
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|                 ));
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|                 *num += 1;
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|             },
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|         )
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|         .observe(
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|             |evt: Trigger<Pointer<Out>>, mut texts: Query<&mut TextColor>| {
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|                 let mut color = texts.get_mut(evt.entity()).unwrap();
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|                 color.0 = Color::WHITE;
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|             },
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|         )
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|         .observe(
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|             |evt: Trigger<Pointer<Over>>, mut texts: Query<&mut TextColor>| {
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|                 let mut color = texts.get_mut(evt.entity()).unwrap();
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|                 color.0 = CYAN_400.into();
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|             },
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|         );
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|     // circular base
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|     commands.spawn((
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|         Mesh3d(meshes.add(Circle::new(4.0))),
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|         MeshMaterial3d(materials.add(Color::WHITE)),
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|         Transform::from_rotation(Quat::from_rotation_x(-std::f32::consts::FRAC_PI_2)),
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|     ));
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|     // light
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|     commands.spawn((
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|         PointLight {
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|             shadows_enabled: true,
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|             ..default()
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|         },
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|         Transform::from_xyz(4.0, 8.0, 4.0),
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|     ));
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|     // camera
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|     commands.spawn((
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|         Camera3d::default(),
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|         Transform::from_xyz(-2.5, 4.5, 9.0).looking_at(Vec3::ZERO, Vec3::Y),
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|     ));
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| }
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