docs: add comments explaining the enemy movement system

src/enemy.rs

@@ -3,7 +3,7 @@ use std::f32::consts::PI;
 
 use crate::player::*;
 
-// Define the player component
+// Define the enemy component
 #[derive(Component)]
 pub struct Enemy {
     pub name: String,
@@ -29,19 +29,24 @@ pub fn enemy_movement(
 ) {
     let enemy = enemy_query.single_mut();
 
+    // Bring the player translation into scope
     let mut player_translation = Vec3::ZERO;
     for player_transform in set.p0().iter_mut() {
         player_translation = player_transform.translation;
     }
 
+    // Get the enemy's movement distance (based on movement speed)
     let movement_distance = enemy.movement_speed * time.delta_seconds();
 
     for mut enemy_transform in set.p1().iter_mut() {
+        // Calculate the angle from the enemy to the player's position
         let difference = player_translation - enemy_transform.translation;
-        let angle = difference.y.atan2(difference.x) - PI/2.;
+        let angle = difference.y.atan2(difference.x) - PI/2.; // Subtract PI/2. to orient the enemy correctly
 
+        // Return a Quat for the enemy's movement direction based on the angle
         let movement_direction = Quat::from_axis_angle(Vec3::new(0., 0., 1.), angle);
 
+        // Update the rotation and translation of the enemy
         enemy_transform.rotation = movement_direction;
         enemy_transform.translation += movement_direction * Vec3::Y * movement_distance;
     }