bevy/examples/ui/ui_scaling.rs
Alice Cecile de004da8d5
Rename bevy_render::Color to LegacyColor (#12069)
# Objective

The migration process for `bevy_color` (#12013) will be fairly involved:
there will be hundreds of affected files, and a large number of APIs.

## Solution

To allow us to proceed granularly, we're going to keep both
`bevy_color::Color` (new) and `bevy_render::Color` (old) around until
the migration is complete.

However, simply doing this directly is confusing! They're both called
`Color`, making it very hard to tell when a portion of the code has been
ported.

As discussed in #12056, by renaming the old `Color` type, we can make it
easier to gradually migrate over, one API at a time.

## Migration Guide

THIS MIGRATION GUIDE INTENTIONALLY LEFT BLANK.

This change should not be shipped to end users: delete this section in
the final migration guide!

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
2024-02-24 21:35:32 +00:00

148 lines
4.3 KiB
Rust

//! This example illustrates the [`UiScale`] resource from `bevy_ui`.
use bevy::{prelude::*, text::TextSettings, utils::Duration};
const SCALE_TIME: u64 = 400;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.insert_resource(TextSettings {
allow_dynamic_font_size: true,
..default()
})
.insert_resource(TargetScale {
start_scale: 1.0,
target_scale: 1.0,
target_time: Timer::new(Duration::from_millis(SCALE_TIME), TimerMode::Once),
})
.add_systems(Startup, setup)
.add_systems(
Update,
(change_scaling, apply_scaling.after(change_scaling)),
)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2dBundle::default());
let text_style = TextStyle {
font: asset_server.load("fonts/FiraMono-Medium.ttf"),
font_size: 16.,
color: LegacyColor::BLACK,
};
commands
.spawn(NodeBundle {
style: Style {
width: Val::Percent(50.0),
height: Val::Percent(50.0),
position_type: PositionType::Absolute,
left: Val::Percent(25.),
top: Val::Percent(25.),
justify_content: JustifyContent::SpaceAround,
align_items: AlignItems::Center,
..default()
},
background_color: LegacyColor::ANTIQUE_WHITE.into(),
..default()
})
.with_children(|parent| {
parent
.spawn(NodeBundle {
style: Style {
width: Val::Px(40.0),
height: Val::Px(40.0),
..default()
},
background_color: LegacyColor::RED.into(),
..default()
})
.with_children(|parent| {
parent.spawn(TextBundle::from_section("Size!", text_style));
});
parent.spawn(NodeBundle {
style: Style {
width: Val::Percent(15.0),
height: Val::Percent(15.0),
..default()
},
background_color: LegacyColor::BLUE.into(),
..default()
});
parent.spawn(ImageBundle {
style: Style {
width: Val::Px(30.0),
height: Val::Px(30.0),
..default()
},
image: asset_server.load("branding/icon.png").into(),
..default()
});
});
}
/// System that changes the scale of the ui when pressing up or down on the keyboard.
fn change_scaling(input: Res<ButtonInput<KeyCode>>, mut ui_scale: ResMut<TargetScale>) {
if input.just_pressed(KeyCode::ArrowUp) {
let scale = (ui_scale.target_scale * 2.0).min(8.);
ui_scale.set_scale(scale);
info!("Scaling up! Scale: {}", ui_scale.target_scale);
}
if input.just_pressed(KeyCode::ArrowDown) {
let scale = (ui_scale.target_scale / 2.0).max(1. / 8.);
ui_scale.set_scale(scale);
info!("Scaling down! Scale: {}", ui_scale.target_scale);
}
}
#[derive(Resource)]
struct TargetScale {
start_scale: f32,
target_scale: f32,
target_time: Timer,
}
impl TargetScale {
fn set_scale(&mut self, scale: f32) {
self.start_scale = self.current_scale();
self.target_scale = scale;
self.target_time.reset();
}
fn current_scale(&self) -> f32 {
let completion = self.target_time.fraction();
let t = ease_in_expo(completion);
self.start_scale.lerp(self.target_scale, t)
}
fn tick(&mut self, delta: Duration) -> &Self {
self.target_time.tick(delta);
self
}
fn already_completed(&self) -> bool {
self.target_time.finished() && !self.target_time.just_finished()
}
}
fn apply_scaling(
time: Res<Time>,
mut target_scale: ResMut<TargetScale>,
mut ui_scale: ResMut<UiScale>,
) {
if target_scale.tick(time.delta()).already_completed() {
return;
}
ui_scale.0 = target_scale.current_scale();
}
fn ease_in_expo(x: f32) -> f32 {
if x == 0. {
0.
} else {
2.0f32.powf(5. * x - 5.)
}
}