winit-sonoma-fix/examples/multithreaded.rs
Robert Bragg 0d366ffbda Re-work event loop run() API so it can return a Result
This re-works the portable `run()` API that consumes the `EventLoop` and
runs the loop on the calling thread until the app exits.

This can be supported across _all_ platforms and compared to the
previous `run() -> !` API is now able to return a `Result` status on all
platforms except iOS and Web. Fixes: #2709

By moving away from `run() -> !` we stop calling `std::process::exit()`
internally as a means to kill the process without returning which means
it's possible to return an exit status and applications can return from
their `main()` function normally.

This also fixes Android support where an Activity runs in a thread but
we can't assume to have full ownership of the process (other services
could be running in separate threads).

Additionally all examples have generally been updated so that `main()`
returns a `Result` from `run()`

Fixes: #2709
2023-07-28 03:04:32 +04:00

213 lines
10 KiB
Rust

#![allow(clippy::single_match)]
#[cfg(not(wasm_platform))]
fn main() -> Result<(), impl std::error::Error> {
use std::{collections::HashMap, sync::mpsc, thread, time::Duration};
use simple_logger::SimpleLogger;
use winit::{
dpi::{PhysicalPosition, PhysicalSize, Position, Size},
event::{ElementState, Event, KeyEvent, WindowEvent},
event_loop::EventLoop,
keyboard::{Key, ModifiersState},
window::{CursorGrabMode, CursorIcon, Fullscreen, WindowBuilder, WindowLevel},
};
const WINDOW_COUNT: usize = 3;
const WINDOW_SIZE: PhysicalSize<u32> = PhysicalSize::new(600, 400);
SimpleLogger::new().init().unwrap();
let event_loop = EventLoop::new();
let mut window_senders = HashMap::with_capacity(WINDOW_COUNT);
for _ in 0..WINDOW_COUNT {
let window = WindowBuilder::new()
.with_inner_size(WINDOW_SIZE)
.build(&event_loop)
.unwrap();
let mut video_modes: Vec<_> = window.current_monitor().unwrap().video_modes().collect();
let mut video_mode_id = 0usize;
let (tx, rx) = mpsc::channel();
window_senders.insert(window.id(), tx);
let mut modifiers = ModifiersState::default();
thread::spawn(move || {
while let Ok(event) = rx.recv() {
match event {
WindowEvent::Moved { .. } => {
// We need to update our chosen video mode if the window
// was moved to an another monitor, so that the window
// appears on this monitor instead when we go fullscreen
let previous_video_mode = video_modes.get(video_mode_id).cloned();
video_modes = window.current_monitor().unwrap().video_modes().collect();
video_mode_id = video_mode_id.min(video_modes.len());
let video_mode = video_modes.get(video_mode_id);
// Different monitors may support different video modes,
// and the index we chose previously may now point to a
// completely different video mode, so notify the user
if video_mode != previous_video_mode.as_ref() {
println!(
"Window moved to another monitor, picked video mode: {}",
video_modes.get(video_mode_id).unwrap()
);
}
}
WindowEvent::ModifiersChanged(new) => {
modifiers = new.state();
}
WindowEvent::KeyboardInput {
event:
KeyEvent {
state: ElementState::Released,
logical_key: key,
..
},
..
} => {
use Key::{ArrowLeft, ArrowRight};
window.set_title(&format!("{key:?}"));
let state = !modifiers.shift_key();
match key {
// Cycle through video modes
Key::ArrowRight | Key::ArrowLeft => {
video_mode_id = match key {
ArrowLeft => video_mode_id.saturating_sub(1),
ArrowRight => (video_modes.len() - 1).min(video_mode_id + 1),
_ => unreachable!(),
};
println!("Picking video mode: {}", video_modes[video_mode_id]);
}
// WARNING: Consider using `key_without_modifers()` if available on your platform.
// See the `key_binding` example
Key::Character(ch) => match ch.to_lowercase().as_str() {
"1" => window.set_window_level(WindowLevel::AlwaysOnTop),
"2" => window.set_window_level(WindowLevel::AlwaysOnBottom),
"3" => window.set_window_level(WindowLevel::Normal),
"c" => window.set_cursor_icon(match state {
true => CursorIcon::Progress,
false => CursorIcon::Default,
}),
"d" => window.set_decorations(!state),
"f" => window.set_fullscreen(match (state, modifiers.alt_key()) {
(true, false) => Some(Fullscreen::Borderless(None)),
(true, true) => Some(Fullscreen::Exclusive(
video_modes[video_mode_id].clone(),
)),
(false, _) => None,
}),
"l" if state => {
if let Err(err) = window.set_cursor_grab(CursorGrabMode::Locked)
{
println!("error: {err}");
}
}
"g" if state => {
if let Err(err) =
window.set_cursor_grab(CursorGrabMode::Confined)
{
println!("error: {err}");
}
}
"g" | "l" if !state => {
if let Err(err) = window.set_cursor_grab(CursorGrabMode::None) {
println!("error: {err}");
}
}
"h" => window.set_cursor_visible(!state),
"i" => {
println!("Info:");
println!("-> outer_position : {:?}", window.outer_position());
println!("-> inner_position : {:?}", window.inner_position());
println!("-> outer_size : {:?}", window.outer_size());
println!("-> inner_size : {:?}", window.inner_size());
println!("-> fullscreen : {:?}", window.fullscreen());
}
"l" => window.set_min_inner_size(match state {
true => Some(WINDOW_SIZE),
false => None,
}),
"m" => window.set_maximized(state),
"p" => window.set_outer_position({
let mut position = window.outer_position().unwrap();
let sign = if state { 1 } else { -1 };
position.x += 10 * sign;
position.y += 10 * sign;
position
}),
"q" => window.request_redraw(),
"r" => window.set_resizable(state),
"s" => {
let _ = window.request_inner_size(match state {
true => PhysicalSize::new(
WINDOW_SIZE.width + 100,
WINDOW_SIZE.height + 100,
),
false => WINDOW_SIZE,
});
}
"w" => {
if let Size::Physical(size) = WINDOW_SIZE.into() {
window
.set_cursor_position(Position::Physical(
PhysicalPosition::new(
size.width as i32 / 2,
size.height as i32 / 2,
),
))
.unwrap()
}
}
"z" => {
window.set_visible(false);
thread::sleep(Duration::from_secs(1));
window.set_visible(true);
}
_ => (),
},
_ => (),
}
}
_ => (),
}
}
});
}
event_loop.run(move |event, _event_loop, control_flow| {
match !window_senders.is_empty() {
true => control_flow.set_wait(),
false => control_flow.set_exit(),
};
match event {
Event::WindowEvent { event, window_id } => match event {
WindowEvent::CloseRequested
| WindowEvent::Destroyed
| WindowEvent::KeyboardInput {
event:
KeyEvent {
state: ElementState::Released,
logical_key: Key::Escape,
..
},
..
} => {
window_senders.remove(&window_id);
}
_ => {
if let Some(tx) = window_senders.get(&window_id) {
if let Some(event) = event.to_static() {
tx.send(event).unwrap();
}
}
}
},
_ => {}
}
})
}
#[cfg(wasm_platform)]
fn main() {
panic!("Example not supported on Wasm");
}