thrown projectiles area damage

src/abilities/thrown.rs

@@ -1,10 +1,10 @@
 use super::TriggerState;
 use crate::{
     GameState,
-    abilities::Projectile,
     aim::AimState,
     billboards::Billboard,
     loading_assets::GameAssets,
+    npc::Hit,
     physics_layers::GameLayer,
     player::{Player, PlayerRig},
     sounds::PlaySound,
@@ -23,6 +23,13 @@ struct ThrownProjectile;
 #[reflect(Component)]
 struct AutoRotation(Quat);
 
+#[derive(Event, Debug)]
+struct Explosion {
+    position: Vec3,
+    radius: f32,
+    damage: u32,
+}
+
 #[derive(Resource)]
 struct ShotAssets {
     image: Handle<Image>,
@@ -36,6 +43,33 @@ pub fn plugin(app: &mut App) {
     app.add_systems(Update, shot_collision.run_if(in_state(GameState::Playing)));
     app.add_systems(FixedUpdate, update_auto_rotation);
     app.add_observer(on_trigger_state);
+    app.add_observer(on_explosion);
+}
+
+fn on_explosion(
+    explosion: Trigger<Explosion>,
+    mut commands: Commands,
+    spatial_query: SpatialQuery,
+) {
+    let explosion = explosion.event();
+    let intersections = {
+        spatial_query.shape_intersections(
+            &Collider::sphere(explosion.radius),
+            explosion.position,
+            Quat::default(),
+            &SpatialQueryFilter::default().with_mask(LayerMask(
+                GameLayer::Npc.to_bits() | GameLayer::Player.to_bits(),
+            )),
+        )
+    };
+
+    for entity in intersections.iter() {
+        if let Some(mut e) = commands.get_entity(*entity) {
+            e.trigger(Hit {
+                damage: explosion.damage,
+            });
+        }
+    }
 }
 
 fn setup(mut commands: Commands, assets: Res<GameAssets>, mut sprite_params: Sprite3dParams) {
@@ -103,13 +137,13 @@ fn on_trigger_state(
             .spawn((
                 Name::new("projectile-thrown"),
                 ThrownProjectile,
-                Projectile { damage: 20 },
                 Collider::sphere(0.5),
                 CollisionLayers::new(
                     LayerMask(GameLayer::Projectile.to_bits()),
                     LayerMask(GameLayer::Npc.to_bits() | GameLayer::Level.to_bits()),
                 ),
                 RigidBody::Dynamic,
+                Mass(0.01),
                 LinearVelocity(vel),
                 Visibility::default(),
                 t,
@@ -140,12 +174,14 @@ fn shot_collision(
 
         commands.entity(shot_entity).despawn_recursive();
 
-        let texture_atlas = TextureAtlas {
-            layout: assets.layout.clone(),
-            index: 0,
-        };
-
         commands.trigger(PlaySound::ThrowHit);
+
+        commands.trigger(Explosion {
+            damage: 20,
+            position: shot_pos,
+            radius: 2.,
+        });
+
         commands
             .spawn(
                 Sprite3dBuilder {
@@ -155,7 +191,13 @@ fn shot_collision(
                     unlit: true,
                     ..default()
                 }
-                .bundle_with_atlas(&mut sprite_params, texture_atlas),
+                .bundle_with_atlas(
+                    &mut sprite_params,
+                    TextureAtlas {
+                        layout: assets.layout.clone(),
+                        index: 0,
+                    },
+                ),
             )
             .insert((
                 Billboard,