bevy/examples/window/window_resizing.rs
Joona Aalto 25bfa80e60
Migrate cameras to required components (#15641)
# Objective

Yet another PR for migrating stuff to required components. This time,
cameras!

## Solution

As per the [selected
proposal](https://hackmd.io/tsYID4CGRiWxzsgawzxG_g#Combined-Proposal-1-Selected),
deprecate `Camera2dBundle` and `Camera3dBundle` in favor of `Camera2d`
and `Camera3d`.

Adding a `Camera` without `Camera2d` or `Camera3d` now logs a warning,
as suggested by Cart [on
Discord](https://discord.com/channels/691052431525675048/1264881140007702558/1291506402832945273).
I would personally like cameras to work a bit differently and be split
into a few more components, to avoid some footguns and confusing
semantics, but that is more controversial, and shouldn't block this core
migration.

## Testing

I ran a few 2D and 3D examples, and tried cameras with and without
render graphs.

---

## Migration Guide

`Camera2dBundle` and `Camera3dBundle` have been deprecated in favor of
`Camera2d` and `Camera3d`. Inserting them will now also insert the other
components required by them automatically.
2024-10-05 01:59:52 +00:00

93 lines
2.7 KiB
Rust

//! This example illustrates how to resize windows, and how to respond to a window being resized.
use bevy::{prelude::*, window::WindowResized};
fn main() {
App::new()
.insert_resource(ResolutionSettings {
large: Vec2::new(1920.0, 1080.0),
medium: Vec2::new(800.0, 600.0),
small: Vec2::new(640.0, 360.0),
})
.add_plugins(DefaultPlugins)
.add_systems(Startup, (setup_camera, setup_ui))
.add_systems(Update, (on_resize_system, toggle_resolution))
.run();
}
/// Marker component for the text that displays the current resolution.
#[derive(Component)]
struct ResolutionText;
/// Stores the various window-resolutions we can select between.
#[derive(Resource)]
struct ResolutionSettings {
large: Vec2,
medium: Vec2,
small: Vec2,
}
// Spawns the camera that draws UI
fn setup_camera(mut commands: Commands) {
commands.spawn(Camera2d);
}
// Spawns the UI
fn setup_ui(mut commands: Commands) {
// Node that fills entire background
commands
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.),
..default()
},
..default()
})
.with_children(|root| {
// Text where we display current resolution
root.spawn((
TextBundle::from_section(
"Resolution",
TextStyle {
font_size: 42.0,
..default()
},
),
ResolutionText,
));
});
}
/// This system shows how to request the window to a new resolution
fn toggle_resolution(
keys: Res<ButtonInput<KeyCode>>,
mut windows: Query<&mut Window>,
resolution: Res<ResolutionSettings>,
) {
let mut window = windows.single_mut();
if keys.just_pressed(KeyCode::Digit1) {
let res = resolution.small;
window.resolution.set(res.x, res.y);
}
if keys.just_pressed(KeyCode::Digit2) {
let res = resolution.medium;
window.resolution.set(res.x, res.y);
}
if keys.just_pressed(KeyCode::Digit3) {
let res = resolution.large;
window.resolution.set(res.x, res.y);
}
}
/// This system shows how to respond to a window being resized.
/// Whenever the window is resized, the text will update with the new resolution.
fn on_resize_system(
mut q: Query<&mut Text, With<ResolutionText>>,
mut resize_reader: EventReader<WindowResized>,
) {
let mut text = q.single_mut();
for e in resize_reader.read() {
// When resolution is being changed
text.sections[0].value = format!("{:.1} x {:.1}", e.width, e.height);
}
}