move targeting code into an event handler

src/hud.rs

@@ -21,16 +21,23 @@ pub struct HudPlugin;
 impl Plugin for HudPlugin {
     fn build(&self, app: &mut App) {
         app.add_systems(Startup, setup);
-        app.add_systems(Update, (update, handle_input));
+        app.add_systems(Update, (
+            update,
+            handle_input,
+            handle_target_event,
+            update_target_selectagon,
+        ));
         app.insert_resource(Log {
             logs: VecDeque::with_capacity(LOG_MAX),
             needs_rerendering: true,
         });
         app.insert_resource(FPSUpdateTimer(
                 Timer::from_seconds(HUD_REFRESH_TIME, TimerMode::Repeating)));
+        app.add_event::<TargetEvent>();
     }
 }
 
+#[derive(Event)] pub struct TargetEvent(pub Option<Entity>);
 #[derive(Component)] struct GaugesText;
 #[derive(Component)] struct ChatText;
 #[derive(Component)] struct Reticule;
@@ -574,9 +581,9 @@ fn handle_input(
     mut q_hud: Query<&mut Visibility, With<ToggleableHudElement>>,
     mut ew_sfx: EventWriter<audio::PlaySfxEvent>,
     mut ew_togglemusic: EventWriter<audio::ToggleMusicEvent>,
+    mut ew_target: EventWriter<TargetEvent>,
     mut ambient_light: ResMut<AmbientLight>,
     q_objects: Query<(Entity, &Transform), (With<IsClickable>, Without<IsTargeted>, Without<actor::PlayerDrivesThis>, Without<actor::Player>)>,
-    q_target: Query<Entity, With<IsTargeted>>,
     q_camera: Query<&Transform, With<Camera>>,
 ) {
     if keyboard_input.just_pressed(settings.key_togglehud) {
@@ -601,24 +608,40 @@ fn handle_input(
         if let Ok(camtrans) = q_camera.get_single() {
             let objects: Vec<(Entity, &Transform)> = q_objects.iter().collect();
             if let (Some(new_target), _dist) = camera::find_closest_target::<Entity>(objects, camtrans) {
-                if let Ok(old_target) = q_target.get_single() {
+                ew_target.send(TargetEvent(Some(new_target)));
-                    if old_target != new_target {
+            }
+            else {
+                ew_target.send(TargetEvent(None));
+            }
+        }
+    }
+}
+
+fn handle_target_event(
+    mut commands: Commands,
+    settings: Res<settings::Settings>,
+    mut er_target: EventReader<TargetEvent>,
+    mut ew_sfx: EventWriter<audio::PlaySfxEvent>,
+    q_target: Query<Entity, With<IsTargeted>>,
+) {
+    let mut play_sfx = false;
+
+    for TargetEvent(target) in er_target.read() {
+        for old_target in &q_target {
             commands.entity(old_target).remove::<IsTargeted>();
-                        commands.entity(new_target).insert(IsTargeted);
+            play_sfx = true;
+        }
+        if let Some(entity) = target {
+            commands.entity(*entity).insert(IsTargeted);
+            play_sfx = true;
+        }
+        if play_sfx && !settings.mute_sfx {
             ew_sfx.send(audio::PlaySfxEvent(audio::Sfx::Click));
         }
-                }
+        break; // Only accept a single event per frame
-                else {
-                    commands.entity(new_target).insert(IsTargeted);
-                    ew_sfx.send(audio::PlaySfxEvent(audio::Sfx::Click));
-                }
-            }
-            else {
-                for entity in &q_target {
-                    commands.entity(entity).remove::<IsTargeted>();
-                    ew_sfx.send(audio::PlaySfxEvent(audio::Sfx::Click));
-                }
-            }
     }
 }
+
+fn update_target_selectagon(
+) {
 }