Merge branch 'add_snake'

src/main.rs

@@ -6,10 +6,43 @@ fn main() {
         // but behaves otherwise; see
         // https://github.com/bevyengine/bevy/issues/11734
         .add_systems(Startup, setup_camera)
+        .add_systems(Startup, spawn_snake)
+        // needs to be in Update; if we leave it in
+        // Startup, it'll only be executed once. Makes sense!
+        .add_systems(Update, move_snake)
         .add_plugins(DefaultPlugins)
         .run();
 }
 
 fn setup_camera(mut commands: Commands) {
     commands.spawn(Camera2dBundle::default());
 }
+
+#[derive(Component)]
+struct SnakeHead;
+
+const SNAKE_HEAD_COLOUR: Color = Color::rgb(102.0, 0.0, 204.0);
+
+fn spawn_snake(mut commands: Commands) {
+    commands
+        .spawn(SpriteBundle {
+            sprite: Sprite {
+                color: SNAKE_HEAD_COLOUR,
+                ..default()
+            },
+            transform: Transform {
+                scale: Vec3::new(10.0, 10.0, 10.0),
+                ..default()
+            },
+            ..default()
+        })
+        .insert(SnakeHead);
+}
+
+fn move_snake(mut head_positions: Query<(&SnakeHead, &mut Transform)>) {
+    for (_head, mut transform) in head_positions.iter_mut() {
+        // for now just move the head 2 upwards
+        // as we don't have user input yet
+        transform.translation.y += 2.0;
+    }
+}