# Objective - The current `EventReader::iter` has been determined to cause confusion among new Bevy users. It was suggested by @JoJoJet to rename the method to better clarify its usage. - Solves #9624 ## Solution - Rename `EventReader::iter` to `EventReader::read`. - Rename `EventReader::iter_with_id` to `EventReader::read_with_id`. - Rename `ManualEventReader::iter` to `ManualEventReader::read`. - Rename `ManualEventReader::iter_with_id` to `ManualEventReader::read_with_id`. --- ## Changelog - `EventReader::iter` has been renamed to `EventReader::read`. - `EventReader::iter_with_id` has been renamed to `EventReader::read_with_id`. - `ManualEventReader::iter` has been renamed to `ManualEventReader::read`. - `ManualEventReader::iter_with_id` has been renamed to `ManualEventReader::read_with_id`. - Deprecated `EventReader::iter` - Deprecated `EventReader::iter_with_id` - Deprecated `ManualEventReader::iter` - Deprecated `ManualEventReader::iter_with_id` ## Migration Guide - Existing usages of `EventReader::iter` and `EventReader::iter_with_id` will have to be changed to `EventReader::read` and `EventReader::read_with_id` respectively. - Existing usages of `ManualEventReader::iter` and `ManualEventReader::iter_with_id` will have to be changed to `ManualEventReader::read` and `ManualEventReader::read_with_id` respectively.
		
			
				
	
	
		
			82 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
//! How to use an external thread to run an infinite task and communicate with a channel.
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use bevy::prelude::*;
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// Using crossbeam_channel instead of std as std `Receiver` is `!Sync`
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use crossbeam_channel::{bounded, Receiver};
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use rand::{rngs::StdRng, Rng, SeedableRng};
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use std::time::{Duration, Instant};
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fn main() {
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    App::new()
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        .add_event::<StreamEvent>()
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        .add_plugins(DefaultPlugins)
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        .add_systems(Startup, setup)
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        .add_systems(Update, (read_stream, spawn_text, move_text))
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        .run();
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}
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#[derive(Resource, Deref)]
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struct StreamReceiver(Receiver<u32>);
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#[derive(Event)]
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struct StreamEvent(u32);
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fn setup(mut commands: Commands) {
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    commands.spawn(Camera2dBundle::default());
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    let (tx, rx) = bounded::<u32>(10);
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    std::thread::spawn(move || {
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        let mut rng = StdRng::seed_from_u64(19878367467713);
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        loop {
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            // Everything here happens in another thread
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            // This is where you could connect to an external data source
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            let start_time = Instant::now();
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            let duration = Duration::from_secs_f32(rng.gen_range(0.0..0.2));
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            while start_time.elapsed() < duration {
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                // Spinning for 'duration', simulating doing hard work!
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            }
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            tx.send(rng.gen_range(0..2000)).unwrap();
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        }
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    });
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    commands.insert_resource(StreamReceiver(rx));
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}
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// This system reads from the receiver and sends events to Bevy
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fn read_stream(receiver: Res<StreamReceiver>, mut events: EventWriter<StreamEvent>) {
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    for from_stream in receiver.try_iter() {
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        events.send(StreamEvent(from_stream));
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    }
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}
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fn spawn_text(mut commands: Commands, mut reader: EventReader<StreamEvent>) {
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    let text_style = TextStyle {
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        font_size: 20.0,
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        color: Color::WHITE,
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        ..default()
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    };
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    for (per_frame, event) in reader.read().enumerate() {
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        commands.spawn(Text2dBundle {
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            text: Text::from_section(event.0.to_string(), text_style.clone())
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                .with_alignment(TextAlignment::Center),
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            transform: Transform::from_xyz(per_frame as f32 * 100.0, 300.0, 0.0),
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            ..default()
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        });
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    }
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}
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fn move_text(
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    mut commands: Commands,
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    mut texts: Query<(Entity, &mut Transform), With<Text>>,
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    time: Res<Time>,
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) {
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    for (entity, mut position) in &mut texts {
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        position.translation -= Vec3::new(0.0, 100.0 * time.delta_seconds(), 0.0);
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        if position.translation.y < -300.0 {
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            commands.entity(entity).despawn();
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        }
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    }
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}
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