bevy/examples/window/window_settings.rs
Jan Hohenheim a750cfe4a1
Split CursorOptions off of Window (#19668)
# Objective

- Fixes #19627 
- Tackles part of #19644 
- Supersedes #19629
- `Window` has become a very very very big component
- As such, our change detection does not *really* work on it, as e.g.
moving the mouse will cause a change for the entire window
- We circumvented this with a cache
- But, some things *shouldn't* be cached as they can be changed from
outside the user's control, notably the cursor grab mode on web
- So, we need to disable the cache for that
- But because change detection is broken, that would result in the
cursor grab mode being set every frame the mouse is moved
- That is usually *not* what a dev wants, as it forces the cursor to be
locked even when the end-user is trying to free the cursor on the
browser
  - the cache in this situation is invalid due to #8949

## Solution

- Split `Window` into multiple components, each with working change
detection
- Disable caching of the cursor grab mode
- This will only attempt to force the grab mode when the `CursorOptions`
were touched by the user, which is *much* rarer than simply moving the
mouse.
- If this PR is merged, I'll do the exact same for the other
constituents of `Window` as a follow-up

## Testing

- Ran all the changed examples
2025-06-17 20:20:13 +00:00

201 lines
7.5 KiB
Rust

//! Illustrates how to change window settings and shows how to affect
//! the mouse pointer in various ways.
#[cfg(feature = "custom_cursor")]
use bevy::winit::cursor::{CustomCursor, CustomCursorImage};
use bevy::{
diagnostic::{FrameCount, FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
prelude::*,
window::{
CursorGrabMode, CursorOptions, PresentMode, SystemCursorIcon, WindowLevel, WindowTheme,
},
winit::cursor::CursorIcon,
};
fn main() {
App::new()
.add_plugins((
DefaultPlugins.set(WindowPlugin {
primary_window: Some(Window {
title: "I am a window!".into(),
name: Some("bevy.app".into()),
resolution: (500., 300.).into(),
present_mode: PresentMode::AutoVsync,
// Tells Wasm to resize the window according to the available canvas
fit_canvas_to_parent: true,
// Tells Wasm not to override default event handling, like F5, Ctrl+R etc.
prevent_default_event_handling: false,
window_theme: Some(WindowTheme::Dark),
enabled_buttons: bevy::window::EnabledButtons {
maximize: false,
..Default::default()
},
// This will spawn an invisible window
// The window will be made visible in the make_visible() system after 3 frames.
// This is useful when you want to avoid the white window that shows up before the GPU is ready to render the app.
visible: false,
..default()
}),
..default()
}),
LogDiagnosticsPlugin::default(),
FrameTimeDiagnosticsPlugin::default(),
))
.add_systems(Startup, init_cursor_icons)
.add_systems(
Update,
(
change_title,
toggle_theme,
toggle_cursor,
toggle_vsync,
toggle_window_controls,
cycle_cursor_icon,
switch_level,
make_visible,
),
)
.run();
}
fn make_visible(mut window: Single<&mut Window>, frames: Res<FrameCount>) {
// The delay may be different for your app or system.
if frames.0 == 3 {
// At this point the gpu is ready to show the app so we can make the window visible.
// Alternatively, you could toggle the visibility in Startup.
// It will work, but it will have one white frame before it starts rendering
window.visible = true;
}
}
/// This system toggles the vsync mode when pressing the button V.
/// You'll see fps increase displayed in the console.
fn toggle_vsync(input: Res<ButtonInput<KeyCode>>, mut window: Single<&mut Window>) {
if input.just_pressed(KeyCode::KeyV) {
window.present_mode = if matches!(window.present_mode, PresentMode::AutoVsync) {
PresentMode::AutoNoVsync
} else {
PresentMode::AutoVsync
};
info!("PRESENT_MODE: {:?}", window.present_mode);
}
}
/// This system switches the window level when pressing the T button
/// You'll notice it won't be covered by other windows, or will be covered by all the other
/// windows depending on the level.
///
/// This feature only works on some platforms. Please check the
/// [documentation](https://docs.rs/bevy/latest/bevy/prelude/struct.Window.html#structfield.window_level)
/// for more details.
fn switch_level(input: Res<ButtonInput<KeyCode>>, mut window: Single<&mut Window>) {
if input.just_pressed(KeyCode::KeyT) {
window.window_level = match window.window_level {
WindowLevel::AlwaysOnBottom => WindowLevel::Normal,
WindowLevel::Normal => WindowLevel::AlwaysOnTop,
WindowLevel::AlwaysOnTop => WindowLevel::AlwaysOnBottom,
};
info!("WINDOW_LEVEL: {:?}", window.window_level);
}
}
/// This system toggles the window controls when pressing buttons 1, 2 and 3
///
/// This feature only works on some platforms. Please check the
/// [documentation](https://docs.rs/bevy/latest/bevy/prelude/struct.Window.html#structfield.enabled_buttons)
/// for more details.
fn toggle_window_controls(input: Res<ButtonInput<KeyCode>>, mut window: Single<&mut Window>) {
let toggle_minimize = input.just_pressed(KeyCode::Digit1);
let toggle_maximize = input.just_pressed(KeyCode::Digit2);
let toggle_close = input.just_pressed(KeyCode::Digit3);
if toggle_minimize || toggle_maximize || toggle_close {
if toggle_minimize {
window.enabled_buttons.minimize = !window.enabled_buttons.minimize;
}
if toggle_maximize {
window.enabled_buttons.maximize = !window.enabled_buttons.maximize;
}
if toggle_close {
window.enabled_buttons.close = !window.enabled_buttons.close;
}
}
}
/// This system will then change the title during execution
fn change_title(mut window: Single<&mut Window>, time: Res<Time>) {
window.title = format!(
"Seconds since startup: {}",
time.elapsed().as_secs_f32().round()
);
}
fn toggle_cursor(mut cursor_options: Single<&mut CursorOptions>, input: Res<ButtonInput<KeyCode>>) {
if input.just_pressed(KeyCode::Space) {
cursor_options.visible = !cursor_options.visible;
cursor_options.grab_mode = match cursor_options.grab_mode {
CursorGrabMode::None => CursorGrabMode::Locked,
CursorGrabMode::Locked | CursorGrabMode::Confined => CursorGrabMode::None,
};
}
}
// This system will toggle the color theme used by the window
fn toggle_theme(mut window: Single<&mut Window>, input: Res<ButtonInput<KeyCode>>) {
if input.just_pressed(KeyCode::KeyF) {
if let Some(current_theme) = window.window_theme {
window.window_theme = match current_theme {
WindowTheme::Light => Some(WindowTheme::Dark),
WindowTheme::Dark => Some(WindowTheme::Light),
};
}
}
}
#[derive(Resource)]
struct CursorIcons(Vec<CursorIcon>);
fn init_cursor_icons(
mut commands: Commands,
#[cfg(feature = "custom_cursor")] asset_server: Res<AssetServer>,
) {
commands.insert_resource(CursorIcons(vec![
SystemCursorIcon::Default.into(),
SystemCursorIcon::Pointer.into(),
SystemCursorIcon::Wait.into(),
SystemCursorIcon::Text.into(),
#[cfg(feature = "custom_cursor")]
CustomCursor::Image(CustomCursorImage {
handle: asset_server.load("branding/icon.png"),
hotspot: (128, 128),
..Default::default()
})
.into(),
]));
}
/// This system cycles the cursor's icon through a small set of icons when clicking
fn cycle_cursor_icon(
mut commands: Commands,
window: Single<Entity, With<Window>>,
input: Res<ButtonInput<MouseButton>>,
mut index: Local<usize>,
cursor_icons: Res<CursorIcons>,
) {
if input.just_pressed(MouseButton::Left) {
*index = (*index + 1) % cursor_icons.0.len();
commands
.entity(*window)
.insert(cursor_icons.0[*index].clone());
} else if input.just_pressed(MouseButton::Right) {
*index = if *index == 0 {
cursor_icons.0.len() - 1
} else {
*index - 1
};
commands
.entity(*window)
.insert(cursor_icons.0[*index].clone());
}
}