Add basic player movement system

src/main.rs

@@ -19,5 +19,6 @@ fn main() {
         .add_plugins(DefaultPlugins)
         .add_startup_system(setup.system())
         .add_startup_system(add_player.system())
+        .add_system(player_movement.system())
         .run();
 }

src/systems/mod.rs

@@ -50,6 +50,35 @@ pub fn add_player(
         });
 }
 
+pub fn player_movement(
+    keyboard_input: Res<Input<KeyCode>>,
+    mut query: Query<(&Player, &mut Transform)>,
+    time: Res<Time>,
+) {
+    if let Ok((_, mut transform)) = query.single_mut() {
+        let mut direction = Vec2::ZERO;
+
+        if keyboard_input.pressed(KeyCode::A) {
+            direction.x -= 1.0;
+        }
+        if keyboard_input.pressed(KeyCode::D) {
+            direction.x += 1.0;
+        }
+        if keyboard_input.pressed(KeyCode::S) {
+            direction.y -= 1.0;
+        }
+        if keyboard_input.pressed(KeyCode::W) {
+            direction.y += 1.0;
+        }
+
+        let translation = &mut transform.translation;
+        let delta_seconds = time.delta_seconds();
+
+        translation.x += delta_seconds * direction.x * 100.0;
+        translation.y += delta_seconds * direction.y * 100.0;
+    }
+}
+
 pub fn greet_player(
     query: Query<&Name, With<Player>>,
     time: Res<Time>,