# 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(); } } ```
		
			
				
	
	
		
			82 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
//! Showcase how to use and configure FPS overlay.
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use bevy::{
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    dev_tools::fps_overlay::{FpsOverlayConfig, FpsOverlayPlugin},
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    prelude::*,
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    text::FontSmoothing,
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};
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struct OverlayColor;
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impl OverlayColor {
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    const RED: Color = Color::srgb(1.0, 0.0, 0.0);
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    const GREEN: Color = Color::srgb(0.0, 1.0, 0.0);
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}
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fn main() {
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    App::new()
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        .add_plugins((
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            DefaultPlugins,
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            FpsOverlayPlugin {
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                config: FpsOverlayConfig {
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                    text_config: TextFont {
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                        // Here we define size of our overlay
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                        font_size: 42.0,
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                        // If we want, we can use a custom font
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                        font: default(),
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                        // We could also disable font smoothing,
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                        font_smoothing: FontSmoothing::default(),
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                    },
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                    // We can also change color of the overlay
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                    text_color: OverlayColor::GREEN,
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                    enabled: true,
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                },
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            },
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        ))
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        .add_systems(Startup, setup)
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        .add_systems(Update, customize_config)
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        .run();
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}
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fn setup(mut commands: Commands) {
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    // We need to spawn a camera (2d or 3d) to see the overlay
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    commands.spawn(Camera2d);
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    // Instruction text
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    commands.spawn((
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        Text::new(concat!(
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            "Press 1 to toggle the overlay color.\n",
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            "Press 2 to decrease the overlay size.\n",
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            "Press 3 to increase the overlay size.\n",
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            "Press 4 to toggle the overlay visibility."
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        )),
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        Node {
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            position_type: PositionType::Absolute,
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            bottom: Val::Px(12.),
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            left: Val::Px(12.),
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            ..default()
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        },
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    ));
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}
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fn customize_config(input: Res<ButtonInput<KeyCode>>, mut overlay: ResMut<FpsOverlayConfig>) {
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    if input.just_pressed(KeyCode::Digit1) {
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        // Changing resource will affect overlay
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        if overlay.text_color == OverlayColor::GREEN {
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            overlay.text_color = OverlayColor::RED;
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        } else {
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            overlay.text_color = OverlayColor::GREEN;
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        }
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    }
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    if input.just_pressed(KeyCode::Digit2) {
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        overlay.text_config.font_size -= 2.0;
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    }
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    if input.just_pressed(KeyCode::Digit3) {
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        overlay.text_config.font_size += 2.0;
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    }
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    if input.just_pressed(KeyCode::Digit4) {
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        overlay.enabled = !overlay.enabled;
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    }
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}
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