use happy_feet as kinematic character controller (#42)

src/head_drop.rs

@@ -88,15 +88,24 @@ fn on_head_drop(
     commands
         .spawn((
             Name::new("headdrop"),
-            HeadDrop(drop.head_id),
             Transform::from_translation(drop.pos),
             Visibility::default(),
             Collider::sphere(1.5),
             LockedAxes::ROTATION_LOCKED,
             RigidBody::Dynamic,
-            CollisionLayers::new(LayerMask(GameLayer::Collectibles.to_bits()), LayerMask::ALL),
+            CollisionLayers::new(
+                GameLayer::CollectiblePhysics,
+                LayerMask::ALL & !GameLayer::Player.to_bits(),
+            ),
             CollisionEventsEnabled,
             Restitution::new(0.6),
+            children![(
+                Collider::sphere(1.5),
+                CollisionLayers::new(GameLayer::CollectibleSensors, GameLayer::Player),
+                Sensor,
+                CollisionEventsEnabled,
+                HeadDrop(drop.head_id),
+            )],
         ))
         .insert_if(
             ExternalImpulse::new(spawn_dir * 180.).with_persistence(false),
@@ -115,7 +124,7 @@ fn collect_head(
     mut commands: Commands,
     mut collision_event_reader: EventReader<CollisionStarted>,
     query_player: Query<&Player>,
-    query_collectable: Query<&HeadDrop>,
+    query_collectable: Query<(&HeadDrop, &ChildOf)>,
     query_secret: Query<&SecretHeadMarker>,
 ) {
     for CollisionStarted(e1, e2) in collision_event_reader.read() {
@@ -127,7 +136,7 @@ fn collect_head(
             continue;
         };
 
-        let key = query_collectable.get(collectable).unwrap();
+        let (key, child_of) = query_collectable.get(collectable).unwrap();
 
         let is_secret = query_secret.contains(collectable);
 
@@ -137,6 +146,6 @@ fn collect_head(
             commands.trigger(PlaySound::HeadCollect);
         }
         commands.trigger(HeadCollected(key.0));
-        commands.entity(collectable).despawn();
+        commands.entity(child_of.parent()).despawn();
     }
 }