mirror of
https://github.com/bevyengine/bevy
synced 2024-12-22 11:03:06 +00:00
7482a0d26d
Fixes #15834 ## Migration Guide The APIs of `Time`, `Timer` and `Stopwatch` have been cleaned up for consistency with each other and the standard library's `Duration` type. The following methods have been renamed: - `Stowatch::paused` -> `Stopwatch::is_paused` - `Time::elapsed_seconds` -> `Time::elasped_secs` (including `_f64` and `_wrapped` variants)
77 lines
2.5 KiB
Rust
77 lines
2.5 KiB
Rust
//! How to use an external thread to run an infinite task and communicate with a channel.
|
|
|
|
use bevy::prelude::*;
|
|
// Using crossbeam_channel instead of std as std `Receiver` is `!Sync`
|
|
use crossbeam_channel::{bounded, Receiver};
|
|
use rand::{Rng, SeedableRng};
|
|
use rand_chacha::ChaCha8Rng;
|
|
use std::time::{Duration, Instant};
|
|
|
|
fn main() {
|
|
App::new()
|
|
.add_event::<StreamEvent>()
|
|
.add_plugins(DefaultPlugins)
|
|
.add_systems(Startup, setup)
|
|
.add_systems(Update, (read_stream, spawn_text, move_text))
|
|
.run();
|
|
}
|
|
|
|
#[derive(Resource, Deref)]
|
|
struct StreamReceiver(Receiver<u32>);
|
|
|
|
#[derive(Event)]
|
|
struct StreamEvent(u32);
|
|
|
|
fn setup(mut commands: Commands) {
|
|
commands.spawn(Camera2d);
|
|
|
|
let (tx, rx) = bounded::<u32>(10);
|
|
std::thread::spawn(move || {
|
|
// We're seeding the PRNG here to make this example deterministic for testing purposes.
|
|
// This isn't strictly required in practical use unless you need your app to be deterministic.
|
|
let mut rng = ChaCha8Rng::seed_from_u64(19878367467713);
|
|
loop {
|
|
// Everything here happens in another thread
|
|
// This is where you could connect to an external data source
|
|
let start_time = Instant::now();
|
|
let duration = Duration::from_secs_f32(rng.gen_range(0.0..0.2));
|
|
while start_time.elapsed() < duration {
|
|
// Spinning for 'duration', simulating doing hard work!
|
|
}
|
|
|
|
tx.send(rng.gen_range(0..2000)).unwrap();
|
|
}
|
|
});
|
|
|
|
commands.insert_resource(StreamReceiver(rx));
|
|
}
|
|
|
|
// This system reads from the receiver and sends events to Bevy
|
|
fn read_stream(receiver: Res<StreamReceiver>, mut events: EventWriter<StreamEvent>) {
|
|
for from_stream in receiver.try_iter() {
|
|
events.send(StreamEvent(from_stream));
|
|
}
|
|
}
|
|
|
|
fn spawn_text(mut commands: Commands, mut reader: EventReader<StreamEvent>) {
|
|
for (per_frame, event) in reader.read().enumerate() {
|
|
commands.spawn((
|
|
Text2d::new(event.0.to_string()),
|
|
TextLayout::new_with_justify(JustifyText::Center),
|
|
Transform::from_xyz(per_frame as f32 * 100.0, 300.0, 0.0),
|
|
));
|
|
}
|
|
}
|
|
|
|
fn move_text(
|
|
mut commands: Commands,
|
|
mut texts: Query<(Entity, &mut Transform), With<Text2d>>,
|
|
time: Res<Time>,
|
|
) {
|
|
for (entity, mut position) in &mut texts {
|
|
position.translation -= Vec3::new(0.0, 100.0 * time.delta_secs(), 0.0);
|
|
if position.translation.y < -300.0 {
|
|
commands.entity(entity).despawn();
|
|
}
|
|
}
|
|
}
|