Find out when a tweener is done repeating

[musjj]

It looks like that when you use something like Repeat::times(8), SpanTweenerEnded is reported every time a repetition is completed. Is there a way to find out when the tweener is actually done?

[musjj]

Never mind, you can do that pretty easily:

if let Some(repeat) = ended.with_repeat {
    if repeat.exhausted() {
        // do something
    }
}

[musjj]

Hmmm, I'm getting a weird behavior here. Let's say I have Repeat::times(8) and I have this code:

if let Some(repeat) = ended.with_repeat {
    println!("repeat");
    if repeat.exhausted() {
        println!("done");
    }
}

This is what I see in the console:

repeat
repeat
repeat
repeat
repeat
repeat
repeat
repeat
done
repeat
done

What's going on here?

[Multirious]

Is it possibly because of how events are buffered by 1 frame? If repeat.exhausted() is fired 2 times per entity then surely one of my example must have caught it. (The example click use the event to remove an entity after completion. It would've crashed if the entity is despawned 2 times) I will do further testing for Repeat::times (I didn't bother testing them 😅).

Site note: You can use the is_completed method on the event.

[Multirious]

Here the test result came back

use bevy::prelude::*;
use bevy_tween::prelude::*;

fn main() {
    App::new()
        .add_plugins((MinimalPlugins, DefaultTweenPlugins))
        .add_systems(Startup, setup)
        .add_systems(Update, check_event)
        .run();
}

fn setup(mut commands: Commands) {
    commands.spawn(SpanTweenerBundle::new(Duration::from_secs(2)).with_repeat(Repeat::times(3)));
}

fn check_event(mut event: EventReader<SpanTweenerEnded>) {
    for ended in event.read() {
        if let Some(repeat) = ended.with_repeat {
            if repeat.exhausted() {
                println!("done");
            } else {
                println!("repeated");
            }
        }
    }
}

output:

repeated
repeated
repeated
done

seems good to me

[musjj]

This isn't the same bug, but I think the problem was related with RepeatStyle::PingPong. This only prints done once (with the latest main):

use bevy::prelude::*;
use bevy_tween::prelude::*;

fn main() {
    App::new()
        .add_plugins((MinimalPlugins, DefaultTweenPlugins))
        .add_systems(Startup, setup)
        .add_systems(Update, check_event)
        .run();
}

fn setup(mut commands: Commands) {
    commands.spawn(
        SpanTweenerBundle::new(Duration::from_secs_f32(0.5))
            .with_repeat(Repeat::times(8))
            .with_repeat_style(RepeatStyle::PingPong),
    );
}

fn check_event(mut event: EventReader<SpanTweenerEnded>) {
    for ended in event.read() {
        if ended.is_completed() {
            println!("done");
        } else {
            println!("repeated");
        }
    }
}

[Multirious]

Apparently the bug is introduced by bd6841c 🙈. Now fixed by eac77aa

[musjj]

Thanks, it works fine now! No idea what was causing the original problem, but I can't reproduce it anymore.