bevy/examples/ui/font_atlas_debug.rs
Lena Milizé 73605f43b6 Replace the bool argument of Timer with TimerMode (#6247)
As mentioned in #2926, it's better to have an explicit type that clearly communicates the intent of the timer mode rather than an opaque boolean, which can be only understood when knowing the signature or having to look up the documentation.

This also opens up a way to merge different timers, such as `Stopwatch`, and possibly future ones, such as `DiscreteStopwatch` and `DiscreteTimer` from #2683, into one struct.

Signed-off-by: Lena Milizé <me@lvmn.org>

# Objective

Fixes #2926.

## Solution

Introduce `TimerMode` which replaces the `bool` argument of `Timer` constructors. A `Default` value for `TimerMode` is `Once`.

---

## Changelog

### Added

- `TimerMode` enum, along with variants `TimerMode::Once` and `TimerMode::Repeating`

### Changed

- Replace `bool` argument of `Timer::new` and `Timer::from_seconds` with `TimerMode`
- Change `repeating: bool` field of `Timer` with `mode: TimerMode`

## Migration Guide

- Replace `Timer::new(duration, false)` with `Timer::new(duration, TimerMode::Once)`.
- Replace `Timer::new(duration, true)` with `Timer::new(duration, TimerMode::Repeating)`.
- Replace `Timer::from_seconds(seconds, false)` with `Timer::from_seconds(seconds, TimerMode::Once)`.
- Replace `Timer::from_seconds(seconds, true)` with `Timer::from_seconds(seconds, TimerMode::Repeating)`.
- Change `timer.repeating()` to `timer.mode() == TimerMode::Repeating`.
2022-10-17 13:47:01 +00:00

108 lines
3.2 KiB
Rust

//! This example illustrates how `FontAtlas`'s are populated.
//! Bevy uses `FontAtlas`'s under the hood to optimize text rendering.
use bevy::{prelude::*, text::FontAtlasSet};
fn main() {
App::new()
.init_resource::<State>()
.insert_resource(ClearColor(Color::BLACK))
.add_plugins(DefaultPlugins)
.add_startup_system(setup)
.add_system(text_update_system)
.add_system(atlas_render_system)
.run();
}
#[derive(Resource)]
struct State {
atlas_count: u32,
handle: Handle<Font>,
timer: Timer,
}
impl Default for State {
fn default() -> Self {
Self {
atlas_count: 0,
handle: Handle::default(),
timer: Timer::from_seconds(0.05, TimerMode::Repeating),
}
}
}
fn atlas_render_system(
mut commands: Commands,
mut state: ResMut<State>,
font_atlas_sets: Res<Assets<FontAtlasSet>>,
texture_atlases: Res<Assets<TextureAtlas>>,
) {
if let Some(set) = font_atlas_sets.get(&state.handle.as_weak::<FontAtlasSet>()) {
if let Some((_size, font_atlas)) = set.iter().next() {
let x_offset = state.atlas_count as f32;
if state.atlas_count == font_atlas.len() as u32 {
return;
}
let texture_atlas = texture_atlases
.get(&font_atlas[state.atlas_count as usize].texture_atlas)
.unwrap();
state.atlas_count += 1;
commands.spawn(ImageBundle {
image: texture_atlas.texture.clone().into(),
style: Style {
position_type: PositionType::Absolute,
position: UiRect {
top: Val::Px(0.0),
left: Val::Px(512.0 * x_offset),
..default()
},
..default()
},
..default()
});
}
}
}
fn text_update_system(mut state: ResMut<State>, time: Res<Time>, mut query: Query<&mut Text>) {
if state.timer.tick(time.delta()).finished() {
for mut text in &mut query {
let c = rand::random::<u8>() as char;
let string = &mut text.sections[0].value;
if !string.contains(c) {
string.push(c);
}
}
state.timer.reset();
}
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>, mut state: ResMut<State>) {
let font_handle = asset_server.load("fonts/FiraSans-Bold.ttf");
state.handle = font_handle.clone();
commands.spawn(Camera2dBundle::default());
commands
.spawn(NodeBundle {
background_color: Color::NONE.into(),
style: Style {
position_type: PositionType::Absolute,
position: UiRect {
bottom: Val::Px(0.0),
..default()
},
..default()
},
..default()
})
.with_children(|parent| {
parent.spawn(TextBundle::from_section(
"a",
TextStyle {
font: font_handle,
font_size: 60.0,
color: Color::YELLOW,
},
));
});
}