 25bfa80e60
			
		
	
	
		25bfa80e60
		
			
		
	
	
	
	
		
			
			# 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.
		
			
				
	
	
		
			81 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! How to use an external thread to run an infinite task and communicate with a channel.
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| 
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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::{Rng, SeedableRng};
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| use rand_chacha::ChaCha8Rng;
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| use std::time::{Duration, Instant};
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| 
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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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| 
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| #[derive(Resource, Deref)]
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| struct StreamReceiver(Receiver<u32>);
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| 
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| #[derive(Event)]
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| struct StreamEvent(u32);
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| 
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| fn setup(mut commands: Commands) {
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|     commands.spawn(Camera2d);
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| 
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|     let (tx, rx) = bounded::<u32>(10);
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|     std::thread::spawn(move || {
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|         // We're seeding the PRNG here to make this example deterministic for testing purposes.
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|         // This isn't strictly required in practical use unless you need your app to be deterministic.
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|         let mut rng = ChaCha8Rng::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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| 
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|             tx.send(rng.gen_range(0..2000)).unwrap();
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|         }
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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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| 
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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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| 
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| fn spawn_text(mut commands: Commands, mut reader: EventReader<StreamEvent>) {
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|     let text_style = TextStyle::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_justify(JustifyText::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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| 
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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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