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(); } } ```
97 lines
3.3 KiB
Rust
97 lines
3.3 KiB
Rust
//! This example illustrates how to create buttons with their textures sliced
|
|
//! and kept in proportion instead of being stretched by the button dimensions
|
|
|
|
use bevy::{
|
|
color::palettes::css::{GOLD, ORANGE},
|
|
prelude::*,
|
|
winit::WinitSettings,
|
|
};
|
|
|
|
fn main() {
|
|
App::new()
|
|
.add_plugins(DefaultPlugins)
|
|
// Only run the app when there is user input. This will significantly reduce CPU/GPU use.
|
|
.insert_resource(WinitSettings::desktop_app())
|
|
.add_systems(Startup, setup)
|
|
.add_systems(Update, button_system)
|
|
.run();
|
|
}
|
|
|
|
fn button_system(
|
|
mut interaction_query: Query<
|
|
(&Interaction, &Children, &mut UiImage),
|
|
(Changed<Interaction>, With<Button>),
|
|
>,
|
|
mut text_query: Query<&mut Text>,
|
|
) {
|
|
for (interaction, children, mut image) in &mut interaction_query {
|
|
let mut text = text_query.get_mut(children[0]).unwrap();
|
|
match *interaction {
|
|
Interaction::Pressed => {
|
|
**text = "Press".to_string();
|
|
image.color = GOLD.into();
|
|
}
|
|
Interaction::Hovered => {
|
|
**text = "Hover".to_string();
|
|
image.color = ORANGE.into();
|
|
}
|
|
Interaction::None => {
|
|
**text = "Button".to_string();
|
|
image.color = Color::WHITE;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
|
|
let image = asset_server.load("textures/fantasy_ui_borders/panel-border-010.png");
|
|
|
|
let slicer = TextureSlicer {
|
|
border: BorderRect::square(22.0),
|
|
center_scale_mode: SliceScaleMode::Stretch,
|
|
sides_scale_mode: SliceScaleMode::Stretch,
|
|
max_corner_scale: 1.0,
|
|
};
|
|
// ui camera
|
|
commands.spawn(Camera2d);
|
|
commands
|
|
.spawn(Node {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
align_items: AlignItems::Center,
|
|
justify_content: JustifyContent::Center,
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
for [w, h] in [[150.0, 150.0], [300.0, 150.0], [150.0, 300.0]] {
|
|
parent
|
|
.spawn((
|
|
Button,
|
|
Node {
|
|
width: Val::Px(w),
|
|
height: Val::Px(h),
|
|
// horizontally center child text
|
|
justify_content: JustifyContent::Center,
|
|
// vertically center child text
|
|
align_items: AlignItems::Center,
|
|
margin: UiRect::all(Val::Px(20.0)),
|
|
..default()
|
|
},
|
|
UiImage::new(image.clone()),
|
|
ImageScaleMode::Sliced(slicer.clone()),
|
|
))
|
|
.with_children(|parent| {
|
|
parent.spawn((
|
|
Text::new("Button"),
|
|
TextFont {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
font_size: 33.0,
|
|
..default()
|
|
},
|
|
TextColor(Color::srgb(0.9, 0.9, 0.9)),
|
|
));
|
|
});
|
|
}
|
|
});
|
|
}
|