feat: initial commit

Signed-off-by: Harald Hoyer <harald@hoyer.xyz>

src/main.rs

@@ -0,0 +1,212 @@
+use bevy::prelude::*;
+use std::time::Duration;
+
+const WINDOW_WIDTH: f32 = 600.0;
+const WINDOW_HEIGHT: f32 = 800.0;
+const PLAYER_SPEED: f32 = 300.0;
+const BULLET_SPEED: f32 = 500.0;
+const ENEMY_SPEED: f32 = 100.0;
+
+#[derive(Component)]
+struct Player {
+    speed: f32,
+    shoot_cooldown: Timer,
+}
+
+#[derive(Component)]
+struct Bullet;
+
+#[derive(Component)]
+struct Enemy;
+
+#[derive(Resource)]
+struct EnemySpawnTimer {
+    timer: Timer,
+}
+
+fn main() {
+    App::new()
+        .insert_resource(ClearColor(Color::rgb(0.0, 0.0, 0.0)))
+        .add_plugins(DefaultPlugins.set(WindowPlugin {
+            primary_window: Some(Window {
+                title: "Galaga".into(),
+                resolution: (WINDOW_WIDTH, WINDOW_HEIGHT).into(),
+                ..default()
+            }),
+            ..default()
+        }))
+        .add_systems(Startup, setup)
+        .add_systems(Update, (
+            move_player,
+            player_shoot,
+            move_bullets,
+            move_enemies,
+            check_bullet_collisions,
+            spawn_enemies,
+        ))
+        .insert_resource(EnemySpawnTimer {
+            timer: Timer::new(Duration::from_secs_f32(0.5), TimerMode::Repeating),
+        })
+        .run();
+}
+
+fn setup(mut commands: Commands) {
+    commands.spawn(Camera2dBundle::default());
+
+    // Spawn player
+    commands.spawn((
+        SpriteBundle {
+            sprite: Sprite {
+                color: Color::rgb(0.0, 0.5, 1.0),
+                custom_size: Some(Vec2::new(30.0, 30.0)),
+                ..default()
+            },
+            transform: Transform::from_translation(Vec3::new(0.0, -300.0, 0.0)),
+            ..default()
+        },
+        Player {
+            speed: PLAYER_SPEED,
+            shoot_cooldown: Timer::new(Duration::from_secs_f32(0.5), TimerMode::Once),
+        },
+    ));
+}
+
+fn move_player(
+    keyboard_input: Res<ButtonInput<KeyCode>>,
+    mut query: Query<(&mut Transform, &Player)>,
+    time: Res<Time>,
+) {
+    if let Ok((mut transform, player)) = query.get_single_mut() {
+        let mut direction = 0.0;
+
+        if keyboard_input.pressed(KeyCode::KeyA) || keyboard_input.pressed(KeyCode::ArrowLeft) {
+            direction -= 1.0;
+        }
+
+        if keyboard_input.pressed(KeyCode::KeyD) || keyboard_input.pressed(KeyCode::ArrowRight) {
+            direction += 1.0;
+        }
+
+        transform.translation.x += direction * player.speed * time.delta_seconds();
+        transform.translation.x = transform.translation.x.clamp(-WINDOW_WIDTH / 2.0 + 15.0, WINDOW_WIDTH / 2.0 - 15.0);
+    }
+}
+
+fn player_shoot(
+    keyboard_input: Res<ButtonInput<KeyCode>>,
+    mut query: Query<(&Transform, &mut Player)>,
+    mut commands: Commands,
+    time: Res<Time>,
+) {
+    if let Ok((transform, mut player)) = query.get_single_mut() {
+        player.shoot_cooldown.tick(time.delta());
+
+        if (keyboard_input.just_pressed(KeyCode::Space) || keyboard_input.just_pressed(KeyCode::ArrowUp))
+            && player.shoot_cooldown.finished() {
+            // Reset cooldown
+            player.shoot_cooldown.reset();
+
+            // Spawn bullet
+            commands.spawn((
+                SpriteBundle {
+                    sprite: Sprite {
+                        color: Color::rgb(1.0, 1.0, 1.0),
+                        custom_size: Some(Vec2::new(5.0, 15.0)),
+                        ..default()
+                    },
+                    transform: Transform::from_translation(Vec3::new(
+                        transform.translation.x,
+                        transform.translation.y + 20.0,
+                        0.0
+                    )),
+                    ..default()
+                },
+                Bullet,
+            ));
+        }
+    }
+}
+
+fn move_bullets(
+    mut query: Query<(Entity, &mut Transform), With<Bullet>>,
+    time: Res<Time>,
+    mut commands: Commands,
+) {
+    for (entity, mut transform) in query.iter_mut() {
+        transform.translation.y += BULLET_SPEED * time.delta_seconds();
+
+        // Despawn bullets that go out of screen
+        if transform.translation.y > WINDOW_HEIGHT / 2.0 {
+            commands.entity(entity).despawn();
+        }
+    }
+}
+
+fn spawn_enemies(
+    mut commands: Commands,
+    time: Res<Time>,
+    mut timer: ResMut<EnemySpawnTimer>,
+    enemy_query: Query<&Enemy>,
+) {
+    timer.timer.tick(time.delta());
+
+    // Only spawn if timer finished and we don't have too many enemies
+    if timer.timer.just_finished() {
+        let x_pos = (fastrand::f32() - 0.5) * (WINDOW_WIDTH - 40.0);
+
+        commands.spawn((
+            SpriteBundle {
+                sprite: Sprite {
+                    color: Color::rgb(1.0, 0.2, 0.2),
+                    custom_size: Some(Vec2::new(40.0, 40.0)),
+                    ..default()
+                },
+                transform: Transform::from_translation(Vec3::new(
+                    x_pos,
+                    WINDOW_HEIGHT / 2.0 - 20.0,
+                    0.0
+                )),
+                ..default()
+            },
+            Enemy,
+        ));
+    }
+}
+
+fn move_enemies(
+    mut query: Query<(Entity, &mut Transform), With<Enemy>>,
+    time: Res<Time>,
+    mut commands: Commands,
+) {
+    for (entity, mut transform) in query.iter_mut() {
+        transform.translation.y -= ENEMY_SPEED * time.delta_seconds();
+
+        // Despawn enemies that go out of screen
+        if transform.translation.y < -WINDOW_HEIGHT / 2.0 {
+            commands.entity(entity).despawn();
+        }
+    }
+}
+
+fn check_bullet_collisions(
+    mut commands: Commands,
+    bullet_query: Query<(Entity, &Transform), With<Bullet>>,
+    enemy_query: Query<(Entity, &Transform), With<Enemy>>,
+) {
+    for (bullet_entity, bullet_transform) in bullet_query.iter() {
+        for (enemy_entity, enemy_transform) in enemy_query.iter() {
+            let bullet_pos = bullet_transform.translation;
+            let enemy_pos = enemy_transform.translation;
+
+            // Simple collision detection using distance
+            let distance = bullet_pos.distance(enemy_pos);
+            if distance < 25.0 { // Approximate collision radius
+                // Despawn both bullet and enemy on collision
+                commands.entity(bullet_entity).despawn();
+                commands.entity(enemy_entity).despawn();
+                break;
+            }
+        }
+    }
+}
+