bevy/examples/ui/window_fallthrough.rs
2025-07-07 21:59:15 +02:00

57 lines
2.1 KiB
Rust

//! This example illustrates how have a mouse's clicks/wheel/movement etc fall through the spawned transparent window to a window below.
//! If you build this, and hit 'P' it should toggle on/off the mouse's passthrough.
//! Note: this example will not work on following platforms: iOS / Android / Web / X11. Window fall through is not supported there.
use bevy::{
prelude::*,
window::{CursorOptions, PrimaryWindow, WindowLevel},
};
fn main() {
App::new()
.insert_resource(ClearColor(Color::NONE)) // Use a transparent window, to make effects obvious.
.add_plugins(DefaultPlugins)
.add_observer(configure_window)
.add_systems(Startup, setup)
.add_systems(Update, toggle_mouse_passthrough) // This allows us to hit 'P' to toggle on/off the mouse's passthrough
.run();
}
fn configure_window(trigger: On<Add, PrimaryWindow>, mut window: Query<&mut Window>) {
let mut window = window.get_mut(trigger.target()).unwrap();
window.transparent = true;
window.decorations = true;
window.window_level = WindowLevel::AlwaysOnTop;
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
// UI camera
commands.spawn(Camera2d);
// Text with one span
commands.spawn((
// Accepts a `String` or any type that converts into a `String`, such as `&str`
Text::new("Hit 'P' then scroll/click around!"),
TextFont {
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
font_size: 83.0, // Nice and big so you can see it!
..default()
},
// Set the style of the TextBundle itself.
Node {
position_type: PositionType::Absolute,
bottom: Val::Px(5.),
right: Val::Px(10.),
..default()
},
));
}
// A simple system to handle some keyboard input and toggle on/off the hit test.
fn toggle_mouse_passthrough(
keyboard_input: Res<ButtonInput<KeyCode>>,
mut cursor_options: Single<&mut CursorOptions>,
) {
if keyboard_input.just_pressed(KeyCode::KeyP) {
cursor_options.hit_test = !cursor_options.hit_test;
}
}