init

src/main.rs

@@ -0,0 +1,52 @@
+use bevy::{camera::ScalingMode, color::palettes::css::GREEN, prelude::*};
+
+fn main() {
+    App::new()
+        .add_plugins(DefaultPlugins)
+        .add_systems(Startup, setup)
+        .add_systems(Update, sprite_movement)
+        .add_systems(Update, draw_gizmo)
+        .run();
+}
+
+#[derive(Component)]
+enum Direction {
+    Left,
+    Right,
+}
+
+fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
+    let mut projection = OrthographicProjection::default_2d();
+    projection.scaling_mode = ScalingMode::AutoMin {
+        min_width: 1920.,
+        min_height: 1080.,
+    };
+    commands.spawn((Camera2d, Projection::Orthographic(projection)));
+
+    commands.spawn((
+        Sprite::from_image(asset_server.load("icon.png")),
+        Transform::from_xyz(0., 0., 0.),
+        Direction::Right,
+    ));
+}
+
+/// The sprite is animated by changing its translation depending on the time that has passed since
+/// the last frame.
+fn sprite_movement(time: Res<Time>, mut sprite_position: Query<(&mut Direction, &mut Transform)>) {
+    for (mut logo, mut transform) in &mut sprite_position {
+        match *logo {
+            Direction::Right => transform.translation.x += 150. * time.delta_secs(),
+            Direction::Left => transform.translation.x -= 150. * time.delta_secs(),
+        }
+
+        if transform.translation.x > 200. {
+            *logo = Direction::Left;
+        } else if transform.translation.x < -200. {
+            *logo = Direction::Right;
+        }
+    }
+}
+
+fn draw_gizmo(mut gizmos: Gizmos) {
+    gizmos.rect_2d(Isometry2d::IDENTITY, Vec2::new(1920., 1080.), GREEN);
+}