Add a bunch of stuff (kill stats)

.gitignore

@@ -1 +1,2 @@
 /target
+*.DS_Store

src/main.rs

@@ -4,11 +4,9 @@ use bevy::core::{FixedTimestep, Time, Timer};
 use bevy::input::system::exit_on_esc_system;
 use bevy::input::Input;
 use bevy::math::Vec3;
-use bevy::prelude::{
-    App, AssetServer, Commands, Component, Entity, KeyCode, OrthographicCameraBundle, Query, Res,
-    SystemSet, Transform, Without,
-};
+use bevy::prelude::*;
 use bevy::sprite::{Sprite, SpriteBundle};
+use bevy::text::Text;
 use bevy::window::Windows;
 use bevy::DefaultPlugins;
 use rand::Rng;
@@ -16,6 +14,7 @@ use rand::Rng;
 fn main() {
     App::new()
         .add_plugins(DefaultPlugins)
+        .insert_resource(ArnoldStats::new())
         .add_startup_system(setup)
         .add_system_set(
             SystemSet::new()
@@ -26,7 +25,8 @@ fn main() {
                 .with_system(linear_movement_system)
                 .with_system(expiration_date_system)
                 .with_system(follow_arnold_system)
-                .with_system(enemy_spawner_system),
+                .with_system(enemy_spawner_system)
+                .with_system(update_scoreboard_system),
         )
         .add_system(exit_on_esc_system)
         .run();
@@ -35,60 +35,162 @@ fn main() {
 fn setup(mut commands: Commands, assets: Res<AssetServer>) {
     let arnold_sh = assets.load("arno.png");
 
+    // cameras
     commands.spawn_bundle(OrthographicCameraBundle::new_2d());
+    commands.spawn_bundle(UiCameraBundle::default());
+    // arnold himself
     commands
         .spawn_bundle(SpriteBundle {
             texture: arnold_sh,
             ..Default::default()
         })
-        .insert(EnemySpawner::new(Timer::from_seconds(3.0, true)))
         .insert(Arnold::new())
         .insert(Transform {
             translation: Vec3::new(0.0, 0.0, 0.0),
             ..Default::default()
         });
+    // enemy spawner
+    commands
+        .spawn()
+        .insert(EnemySpawner::new(Timer::from_seconds(3.0, true)));
+    // scoreboard
+    commands
+        .spawn_bundle(TextBundle {
+            text: Text {
+                sections: vec![
+                    TextSection {
+                        style: TextStyle {
+                            font: assets.load("fonts/PressStart2P-Regular.ttf"),
+                            font_size: 15.0,
+                            color: Color::WHITE,
+                        },
+                        value: "kills: ".to_string(),
+                    },
+                    TextSection {
+                        style: TextStyle {
+                            font: assets.load("fonts/PressStart2P-Regular.ttf"),
+                            font_size: 15.0,
+                            color: Color::RED,
+                        },
+                        value: "0".to_string(),
+                    },
+                ],
+                ..Default::default()
+            },
+            style: Style {
+                position_type: PositionType::Absolute,
+                position: Rect {
+                    top: Val::Px(5.0),
+                    left: Val::Px(5.0),
+                    ..Default::default()
+                },
+                ..Default::default()
+            },
+            ..Default::default()
+        })
+        .insert(ScoreBoard);
+}
+
+// Unit struct for tracking the ScoreBoard Text UI
+#[derive(Component)]
+struct ScoreBoard;
+
+fn update_scoreboard_system(
+    stats: Res<ArnoldStats>,
+    mut query: Query<&mut Text, With<ScoreBoard>>,
+) {
+    query.single_mut().sections[1].value = format!("{}", stats.kills);
+}
+
+struct ArnoldStats {
+    damage_dealt: i32,
+    kills: i32,
+}
+
+impl ArnoldStats {
+    fn new() -> Self {
+        Self {
+            damage_dealt: 0,
+            kills: 0,
+        }
+    }
 }
 
 #[derive(Component)]
 struct Projectile {
+    damage: i32,
 }
 
 impl Projectile {
-    fn new() -> Self {
-        Self {}
+    fn new(damage: i32) -> Self {
+        Self { damage }
     }
 }
 
 #[derive(Component)]
 struct Hitpoints {
+    hp: i32,
 }
 
 impl Hitpoints {
-    fn new() -> Self {
-        Self {}
+    fn new(hp: i32) -> Self {
+        Self { hp }
     }
 }
 
 fn projectile_collide_system(
     mut commands: Commands,
+    mut stats: ResMut<ArnoldStats>,
+    assets: Res<AssetServer>,
     projectile_query: Query<(&Projectile, &Transform)>,
-    target_query: Query<(Entity, &Hitpoints, &Transform)>
+    mut target_query: Query<(Entity, &mut Hitpoints, &Transform)>,
 ) {
-    for (entity, _hp, target_transform) in target_query.iter() {
-        let mut has_been_hit = false;
-        for (_projectile, projectile_transform) in projectile_query.iter() {
-            if target_transform.translation.distance(projectile_transform.translation) < 32.0 {
-                has_been_hit = true;
+    for (entity, mut hp, target_transform) in target_query.iter_mut() {
+        for (projectile, projectile_transform) in projectile_query.iter() {
+            if target_transform
+                .translation
+                .distance(projectile_transform.translation)
+                < 32.0
+            {
+                hp.hp -= projectile.damage;
+                stats.damage_dealt += projectile.damage;
+
+                let font = assets.load("fonts/PressStart2P-Regular.ttf");
+                let text_style = TextStyle {
+                    font,
+                    font_size: 10.0,
+                    color: Color::YELLOW,
+                };
+                let text_alignment = TextAlignment {
+                    vertical: VerticalAlign::Center,
+                    horizontal: HorizontalAlign::Center,
+                };
+                commands
+                    .spawn_bundle(Text2dBundle {
+                        text: Text::with_section(
+                            &format!("{}", projectile.damage),
+                            text_style,
+                            text_alignment,
+                        ),
+                        transform: Transform {
+                            translation: target_transform.translation + Vec3::new(0.0, 10.0, 10.0),
+                            ..Default::default()
+                        },
+                        ..Default::default()
+                    })
+                    .insert(ExpirationDate::new(3.0))
+                    .insert(LinearMovement::new(Vec3::new(0.0, 0.5, 0.0)));
             }
         }
 
-        if has_been_hit {
+        if hp.hp <= 0 {
+            stats.kills += 1;
             commands.entity(entity).despawn();
         }
     }
 }
 
-#[derive(PartialEq)]
+#[derive(Clone, Copy, PartialEq)]
 enum Facing {
     Left,
     Right,
@@ -141,8 +243,10 @@ struct ExpirationDate {
 }
 
 impl ExpirationDate {
-    fn new(countdown: Timer) -> Self {
-        Self { countdown }
+    fn new(duration: f32) -> Self {
+        Self {
+            countdown: Timer::from_seconds(duration, false),
+        }
     }
 }
 
@@ -200,30 +304,14 @@ fn arnold_attack_system(
     let (mut arnold, arnold_transform) = query.single_mut();
 
     if arnold.attack_timer.tick(time.delta()).just_finished() {
-        let knife_velocity = match arnold.facing {
-            Facing::Left => Vec3::new(-1.0, 0.0, 0.0),
-            Facing::Right => Vec3::new(1.0, 0.0, 0.0),
-        } * 4.0;
-
-        commands
-            .spawn_bundle(SpriteBundle {
-                texture: assets.load("knife.png"),
-                sprite: Sprite {
-                    flip_x: arnold.facing == Facing::Left,
-                    ..Default::default()
-                },
-                ..Default::default()
-            })
-            .insert(Knife::new())
-            .insert(Transform {
-                translation: arnold_transform.translation
-                    + Vec3::new(0.0, 0.0, 10.0)
-                    + knife_velocity,
-                ..Default::default()
-            })
-            .insert(LinearMovement::new(knife_velocity))
-            .insert(ExpirationDate::new(Timer::from_seconds(5.0, false)))
-            .insert(Projectile::new());
+        commands.spawn_bundle(KnifeBundle::new(
+            assets.load("knife.png"),
+            arnold_transform.translation + Vec3::new(0.0, 0.0, 10.0),
+            arnold.facing,
+            4.0,
+            5.0,
+            10,
+        ));
     }
 }
 
@@ -267,7 +355,53 @@ fn enemy_spawner_system(
             ..Default::default()
         })
         .insert(FollowArnold::new(1.0))
-        .insert(Hitpoints::new());
+        .insert(Hitpoints::new(8));
+}
+
+#[derive(Bundle)]
+struct KnifeBundle {
+    _knife: Knife,
+    #[bundle]
+    sprite: SpriteBundle,
+    lin_movement: LinearMovement,
+    exp_date: ExpirationDate,
+    projectile: Projectile,
+}
+
+impl KnifeBundle {
+    fn new(
+        texture: Handle<Image>,
+        translation: Vec3,
+        facing: Facing,
+        speed: f32,
+        lifetime: f32,
+        damage: i32,
+    ) -> Self {
+        let velocity = match facing {
+            Facing::Left => Vec3::new(-1.0, 0.0, 0.0),
+            Facing::Right => Vec3::new(1.0, 0.0, 0.0),
+        } * speed;
+        let flip_x = velocity.x < 0.0;
+
+        KnifeBundle {
+            _knife: Knife::new(),
+            sprite: SpriteBundle {
+                texture,
+                sprite: Sprite {
+                    flip_x,
+                    ..Default::default()
+                },
+                transform: Transform {
+                    translation,
+                    ..Default::default()
+                },
+                ..Default::default()
+            },
+            lin_movement: LinearMovement::new(velocity),
+            exp_date: ExpirationDate::new(lifetime),
+            projectile: Projectile::new(damage),
+        }
+    }
 }
 
 #[derive(Component)]