68d419d40f
Repeating timers will reset themselves upon finishing, carrying over any excess time during the last tick. This fixes timer drift upon resetting.
57 lines
1.4 KiB
Rust
57 lines
1.4 KiB
Rust
use bevy::prelude::*;
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/// This example creates a new event, a system that triggers the event once per second,
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/// and a system that prints a message whenever the event is received.
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fn main() {
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App::build()
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.add_default_plugins()
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.add_event::<MyEvent>()
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.init_resource::<EventTriggerState>()
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.init_resource::<EventListenerState>()
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.add_system(event_trigger_system.system())
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.add_system(event_listener_system.system())
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.run();
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}
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struct MyEvent {
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pub message: String,
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}
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struct EventTriggerState {
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event_timer: Timer,
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}
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impl Default for EventTriggerState {
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fn default() -> Self {
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EventTriggerState {
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event_timer: Timer::from_seconds(1.0, true),
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}
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}
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}
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// sends MyEvent every second
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fn event_trigger_system(
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time: Res<Time>,
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mut state: ResMut<EventTriggerState>,
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mut my_events: ResMut<Events<MyEvent>>,
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) {
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state.event_timer.tick(time.delta_seconds);
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if state.event_timer.finished {
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my_events.send(MyEvent {
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message: "MyEvent just happened!".to_string(),
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});
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}
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}
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#[derive(Default)]
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struct EventListenerState {
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my_event_reader: EventReader<MyEvent>,
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}
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// prints events as they come in
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fn event_listener_system(mut state: ResMut<EventListenerState>, my_events: Res<Events<MyEvent>>) {
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for my_event in state.my_event_reader.iter(&my_events) {
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println!("{}", my_event.message);
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}
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}
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