♻️ extract camera

Cargo.toml

@@ -5,10 +5,13 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[workspace]
+
 [dependencies]
 bevy = "0.11.3"
 bevy_rapier2d = "0.22.0"
 rand = "0.8.5"
+bevy_camera = { path = "camera" }
 
 # Enable a small amount of optimization in debug mode
 [profile.dev]

camera/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "bevy_camera"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+bevy = "0.11.3"

camera/src/lib.rs

@@ -0,0 +1,61 @@
+use bevy::prelude::{
+    App, Bundle, Camera2dBundle, Component, Entity, Plugin, PostUpdate, Query, Transform, With,
+    Without,
+};
+
+#[derive(Component)]
+pub struct Target;
+
+#[derive(Component)]
+pub struct Camera(pub Entity);
+
+#[derive(Bundle)]
+pub struct CameraBundle {
+    camera: Camera,
+    bundle: Camera2dBundle,
+}
+
+impl CameraBundle {
+    pub fn new(target: Entity, bundle: Camera2dBundle) -> Self {
+        Self {
+            camera: Camera(target),
+            bundle,
+        }
+    }
+
+    pub fn new_with_default_bundle(target: Entity) -> Self {
+        Self {
+            camera: Camera(target),
+            bundle: Camera2dBundle::default(),
+        }
+    }
+}
+
+pub struct CameraPlugin;
+
+impl Plugin for CameraPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(PostUpdate, cameraman);
+    }
+}
+
+fn cameraman(
+    mut query_camera: Query<(&mut Transform, &Camera), Without<Target>>,
+    query_targets: Query<(&Transform, Entity), With<Target>>,
+) {
+    for (mut camera_transform, camera) in &mut query_camera {
+        for (target_transform, target_entity) in &query_targets {
+            if camera.0 != target_entity {
+                continue;
+            }
+
+            // TODO: for now we follow the first target but we could think of doing an average positions of all the targets
+            if camera.0 == target_entity {
+                camera_transform.translation.x = target_transform.translation.x;
+                camera_transform.translation.y = target_transform.translation.y;
+
+                break;
+            }
+        }
+    }
+}

src/main.rs

@@ -12,18 +12,16 @@ use bevy::{
     prelude::*,
     DefaultPlugins,
 };
+use bevy_camera::CameraPlugin;
 use bevy_rapier2d::prelude::*;
 use castles::CastlesPlugin;
 use health::HealthPlugin;
 use minions::MinionsPlugin;
 use physics::PhysicsPlugin;
-use player::{LocalPlayer, LocalPlayerPlugin};
+use player::LocalPlayerPlugin;
 use racks::RacksPlugin;
 use teams::TeamsPlugin;
 
-#[derive(Component)]
-struct Camera;
-
 fn main() {
     let mut app = App::new();
 
@@ -40,6 +38,7 @@ fn main() {
         CastlesPlugin,
         HealthPlugin,
         LocalPlayerPlugin,
+        CameraPlugin,
     ))
     // --- physics ---
     .add_plugins((
@@ -51,25 +50,5 @@ fn main() {
         gravity: Vec2::new(0.0, 0.0),
         ..default()
     })
-    // --- systems ---
-    .add_systems(Startup, setup)
-    .add_systems(Update, cameraman)
     .run();
 }
-
-fn setup(mut commands: Commands) {
-    // Camera
-    commands.spawn((Camera2dBundle::default(), Camera {}));
-}
-
-fn cameraman(
-    mut query_camera: Query<&mut Transform, (With<Camera>, Without<LocalPlayer>)>,
-    query_player: Query<&Transform, With<LocalPlayer>>,
-) {
-    if let Ok(mut camera_transform) = query_camera.get_single_mut() {
-        if let Ok(player_transform) = query_player.get_single() {
-            camera_transform.translation.x = player_transform.translation.x;
-            camera_transform.translation.y = player_transform.translation.y;
-        }
-    }
-}

src/player.rs

@@ -11,6 +11,7 @@ use bevy::{
     sprite::{Sprite, SpriteBundle},
     time::Time,
 };
+use bevy_camera::{Camera, CameraBundle, Target};
 use bevy_rapier2d::prelude::*;
 
 const DEFAULT_HAND_COLOR: Color = Color::rgb(0.8, 0.25, 0.24);
@@ -107,7 +108,7 @@ fn setup(
 
     let team = teams.get_expect("a".into());
 
-    commands
+    let entity = commands
         .spawn((
             MaterialMesh2dBundle {
                 mesh: meshes.add(shape::Circle::new(30.).into()).into(),
@@ -139,6 +140,7 @@ fn setup(
                 .with_health_bar_position(Vec3::new(0.0, 40.0, 0.1))
                 .with_health_bar_size(Vec2::new(50.0, 5.0)),
             Name("local_player".to_string()),
+            Target,
             team,
         ))
         .with_children(|parent| {
@@ -154,7 +156,10 @@ fn setup(
                 },
                 Hand {},
             ));
-        });
+        })
+        .id();
+
+    commands.spawn(CameraBundle::new_with_default_bundle(entity));
 }
 
 fn setup_ui(mut commands: Commands, asset_server: Res<AssetServer>) {