From 42513e79125e06531042a3e80085d31c8aef82e3 Mon Sep 17 00:00:00 2001
From: Nolan Darilek <nolan@thewordnerd.info>
Date: Mon, 26 Jul 2021 15:50:25 -0500
Subject: [PATCH] Store cardinal direction on player.

---
 src/navigation.rs | 38 ++++++++++++++++++++++----------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/src/navigation.rs b/src/navigation.rs
index 6c6adb8..0ff6d99 100644
--- a/src/navigation.rs
+++ b/src/navigation.rs
@@ -174,26 +174,31 @@ fn movement_controls<S, A: 'static>(
     }
 }
 
-fn speak_direction(
-    mut tts: ResMut<Tts>,
-    mut cache: Local<HashMap<Entity, CardinalDirection>>,
-    player: Query<(Entity, &Player, &Transform), Changed<Transform>>,
-) -> Result<(), Box<dyn Error>> {
-    if let Ok((entity, _, transform)) = player.single() {
+fn update_direction(
+    mut commands: Commands,
+    query: Query<
+        (Entity, &Transform, Option<&CardinalDirection>),
+        (With<Player>, Changed<Transform>),
+    >,
+) {
+    for (entity, transform, direction) in query.iter() {
         let forward = transform.local_x();
         let yaw = Angle::Radians(forward.y.atan2(forward.x));
-        if let Some(old_direction) = cache.get(&entity) {
-            let old_direction = *old_direction;
-            let direction: CardinalDirection = yaw.into();
-            if old_direction != direction {
-                let direction: String = direction.into();
-                tts.speak(direction, true)?;
-            }
-            cache.insert(entity, direction);
-        } else {
-            cache.insert(entity, yaw.into());
+        let new_direction: CardinalDirection = yaw.into();
+        if direction != Some(&new_direction) {
+            commands.entity(entity).insert(new_direction);
         }
     }
+}
+
+fn speak_direction(
+    mut tts: ResMut<Tts>,
+    player: Query<&CardinalDirection, (With<Player>, Changed<CardinalDirection>)>,
+) -> Result<(), Box<dyn Error>> {
+    if let Ok(direction) = player.single() {
+        let direction: String = (*direction).into();
+        tts.speak(direction, true)?;
+    }
     Ok(())
 }
 
@@ -258,6 +263,7 @@ where
         app.register_type::<MaxSpeed>()
             .register_type::<RotationSpeed>()
             .register_type::<Sprinting>()
+            .add_system(update_direction.system())
             .add_system(speak_direction.system().chain(error_handler.system()));
         if config.movement_control_states.is_empty() {
             app.add_system(movement_controls::<S, A>.system());