Code cleanup and documentation changes

Author: adamgraham

Assets/Scripts/Asteroid.cs

@@ -5,7 +5,6 @@
 /// </summary>
 [RequireComponent(typeof(SpriteRenderer))]
 [RequireComponent(typeof(Rigidbody2D))]
-[RequireComponent(typeof(BoxCollider2D))]
 public class Asteroid : MonoBehaviour
 {
     /// <summary>
@@ -48,64 +47,57 @@ public class Asteroid : MonoBehaviour
     /// <summary>
     /// The sprite renderer component attached to the asteroid.
     /// </summary>
-    private SpriteRenderer _spriteRenderer;
+    public SpriteRenderer spriteRenderer { get; private set; }
 
     /// <summary>
     /// The rigidbody component attached to the asteroid.
     /// </summary>
-    private Rigidbody2D _rigidbody;
+    public new Rigidbody2D rigidbody { get; private set; }
 
     private void Awake()
     {
-        // Store references to the asteroid's components
-        _rigidbody = GetComponent<Rigidbody2D>();
-        _spriteRenderer = GetComponent<SpriteRenderer>();
+        this.spriteRenderer = GetComponent<SpriteRenderer>();
+        this.rigidbody = GetComponent<Rigidbody2D>();
     }
 
     private void Start()
     {
-        // Assign a random sprite to the asteroid
-        _spriteRenderer.sprite = this.sprites[Random.Range(0, this.sprites.Length)];
-
-        // Assign a random rotation to the asteroid
+        // Assign random properties to make each asteroid feel unique
+        this.spriteRenderer.sprite = this.sprites[Random.Range(0, this.sprites.Length)];
         this.transform.eulerAngles = new Vector3(0.0f, 0.0f, Random.value * 360.0f);
 
-        // Set the scale and mass of the asteroid based on the assigned size
+        // Set the scale and mass of the asteroid based on the assigned size so
+        // the physics is more realistic
         this.transform.localScale = Vector3.one * this.size;
-        _rigidbody.mass = this.size;
+        this.rigidbody.mass = this.size;
 
         // Destroy the asteroid after it reaches its max lifetime
         Destroy(this.gameObject, this.maxLifetime);
     }
 
     public void SetTrajectory(Vector2 direction)
     {
-        // Move the asteroid along the trajectory factoring in its speed
-        _rigidbody.AddForce(direction * this.movementSpeed);
+        // The asteroid only needs a force to be added once since they have no
+        // drag to make them stop moving
+        this.rigidbody.AddForce(direction * this.movementSpeed);
     }
 
     private void OnCollisionEnter2D(Collision2D collision)
     {
-        // Check if the asteroid was hit by a bullet
         if (collision.gameObject.tag == "Bullet")
         {
             // Check if the asteroid is large enough to split in half (both
             // parts must be greater than the minimum size)
             if ((this.size * 0.5f) >= this.minSize)
             {
-                // Split the asteroid into two parts by creating two new
-                // asteroids
                 CreateSplit();
                 CreateSplit();
             }
 
-            // Inform the game manager the asteroid was destroyed so score can
-            // be calculated
             FindObjectOfType<GameManager>().AsteroidDestroyed(this);
 
             // Destroy the current asteroid since it is either replaced by two
-            // new asteroid objects or small enough to be destroyed by the
-            // bullet
+            // new asteroids or small enough to be destroyed by the bullet
             Destroy(this.gameObject);
         }
     }

Assets/Scripts/AsteroidSpawner.cs

@@ -39,7 +39,6 @@ public class AsteroidSpawner : MonoBehaviour
 
     private void Start()
     {
-        // Start spawning an asteroid at a fixed rate
         InvokeRepeating(nameof(Spawn), this.spawnRate, this.spawnRate);
     }
 

Assets/Scripts/Bullet.cs

@@ -4,7 +4,6 @@
 /// Handles the physics/movement of a bullet projectile.
 /// </summary>
 [RequireComponent(typeof(Rigidbody2D))]
-[RequireComponent(typeof(BoxCollider2D))]
 public class Bullet : MonoBehaviour
 {
     /// <summary>
@@ -23,27 +22,26 @@ public class Bullet : MonoBehaviour
     /// <summary>
     /// The rigidbody component attached to the bullet.
     /// </summary>
-    private Rigidbody2D _rigidbody;
+    public new Rigidbody2D rigidbody { get; private set; }
 
     private void Awake()
     {
-        // Store references to the bullet's components
-        _rigidbody = GetComponent<Rigidbody2D>();
+        this.rigidbody = GetComponent<Rigidbody2D>();
     }
 
     public void Project(Vector2 direction)
     {
-        // Move the bullet in the desired direction while factoring in the speed
-        // of the bullet
-        _rigidbody.AddForce(direction * this.speed);
+        // The bullet only needs a force to be added once since they have no
+        // drag to make them stop moving
+        this.rigidbody.AddForce(direction * this.speed);
 
-        // Destroy the bullet after it reaches its max lifetime
+        // Destroy the bullet after it reaches it max lifetime
         Destroy(this.gameObject, this.maxLifetime);
     }
 
     private void OnCollisionEnter2D(Collision2D collision)
     {
-        // Destroy the bullet if it collides with anything
+        // Destroy the bullet as soon as it collides with anything
         Destroy(this.gameObject);
     }
 

Assets/Scripts/GameManager.cs

@@ -2,8 +2,7 @@
 using UnityEngine.UI;
 
 /// <summary>
-/// Manages the state of the game, such as scoring, dying, and starting a new
-/// game.
+/// Manages the state of the game such as scoring, dying, and game over.
 /// </summary>
 public class GameManager : MonoBehaviour
 {
@@ -55,45 +54,39 @@ private void Start()
 
     private void Update()
     {
-        // Start a new game once the player presses 'Return'
         if (this.lives <= 0 && Input.GetKeyDown(KeyCode.Return)) {
             NewGame();
         }
     }
 
     public void NewGame()
     {
-        // Clear the scene of asteroids so we can start fresh
         Asteroid[] asteroids = FindObjectsOfType<Asteroid>();
+
+        // Clear the scene of asteroids so we start fresh
         for (int i = 0; i < asteroids.Length; i++) {
             Destroy(asteroids[i].gameObject);
         }
 
-        // Hide the game over UI
         this.gameOverUI.SetActive(false);
 
-        // Reset score and lives
         SetScore(0);
         SetLives(3);
-
-        // Spawn the player
         Respawn();
     }
 
     public void Respawn()
     {
-        // Move the player back to the center and reactivate their controls
         this.player.transform.position = Vector3.zero;
         this.player.gameObject.SetActive(true);
     }
 
     public void AsteroidDestroyed(Asteroid asteroid)
     {
-        // Play the explosion effect at the location of the asteroid
         this.explosionEffect.transform.position = asteroid.transform.position;
         this.explosionEffect.Play();
 
-        // Increase the score based on the size of the asteroid
+        // Score is increased based on the size of the asteroid
         if (asteroid.size < 0.7f) {
             SetScore(this.score + 100); // small asteroid
         } else if (asteroid.size < 1.4f) {
@@ -105,38 +98,31 @@ public void AsteroidDestroyed(Asteroid asteroid)
 
     public void PlayerDeath(Player player)
     {
-        // Play the explosion effect at the location of the player
         this.explosionEffect.transform.position = player.transform.position;
         this.explosionEffect.Play();
 
-        // Decrement lives by 1
         SetLives(this.lives - 1);
 
-        // Check if a game over state has been reached (no lives)
         if (this.lives <= 0) {
             GameOver();
         } else {
-            // Respawn the player if they have more lives
             Invoke(nameof(Respawn), player.respawnDelay);
         }
     }
 
     public void GameOver()
     {
-        // Show the game over UI
         this.gameOverUI.SetActive(true);
     }
 
     private void SetScore(int score)
     {
-        // Set the score and update the UI text
         this.score = score;
         this.scoreText.text = score.ToString();
     }
 
     private void SetLives(int lives)
     {
-        // Set the lives and update the UI text
         this.lives = lives;
         this.livesText.text = lives.ToString();
     }

Assets/Scripts/Player.cs

@@ -4,7 +4,6 @@
 /// Handles the movement and shooting of the player ship.
 /// </summary>
 [RequireComponent(typeof(Rigidbody2D))]
-[RequireComponent(typeof(BoxCollider2D))]
 public class Player : MonoBehaviour
 {
     /// <summary>
@@ -42,22 +41,21 @@ public class Player : MonoBehaviour
     /// <summary>
     /// The current direction the player is turning. 1=left, -1=right, 0=none
     /// </summary>
-    private float _turnDirection = 0.0f;
+    public float turnDirection { get; private set; } = 0.0f;
 
     /// <summary>
     /// Whether the ship's thrusts are activated causing it to move forward.
     /// </summary>
-    private bool _thrusting = false;
+    public bool thrusting { get; private set; }
 
     /// <summary>
     /// The rigidbody component attached to the player.
     /// </summary>
-    private Rigidbody2D _rigidbody;
+    public new Rigidbody2D rigidbody { get; private set; }
 
     private void Awake()
     {
-        // Store references to the player's components
-        _rigidbody = GetComponent<Rigidbody2D>();
+        this.rigidbody = GetComponent<Rigidbody2D>();
     }
 
     private void OnEnable()
@@ -71,21 +69,16 @@ private void OnEnable()
 
     private void Update()
     {
-        // Activate thrust when pressing the 'w' key or 'up arrow' key
-        _thrusting = Input.GetKey(KeyCode.W) || Input.GetKey(KeyCode.UpArrow);
+        this.thrusting = Input.GetKey(KeyCode.W) || Input.GetKey(KeyCode.UpArrow);
 
-        // Set the turn direction of the ship based on which input key is being
-        // held
         if (Input.GetKey(KeyCode.A) || Input.GetKey(KeyCode.LeftArrow)) {
-            _turnDirection = 1.0f;
+            this.turnDirection = 1.0f;
         } else if (Input.GetKey(KeyCode.D) || Input.GetKey(KeyCode.RightArrow)) {
-            _turnDirection = -1.0f;
+            this.turnDirection = -1.0f;
         } else {
-            _turnDirection = 0.0f;
+            this.turnDirection = 0.0f;
         }
 
-        // Shoot a bullet each time the 'space' key is pressed or when the mouse
-        // left button is clicked
         if (Input.GetKeyDown(KeyCode.Space) || Input.GetMouseButtonDown(0)) {
             Shoot();
         }
@@ -94,19 +87,18 @@ private void Update()
     private void FixedUpdate()
     {
         // Add force to move the ship forward
-        if (_thrusting) {
-            _rigidbody.AddForce(this.transform.up * this.thrustSpeed);
+        if (this.thrusting) {
+            this.rigidbody.AddForce(this.transform.up * this.thrustSpeed);
         }
 
         // Add torque to rotate the ship
-        if (_turnDirection != 0.0f) {
-            _rigidbody.AddTorque(this.rotationSpeed * _turnDirection);
+        if (this.turnDirection != 0.0f) {
+            this.rigidbody.AddTorque(this.rotationSpeed * this.turnDirection);
         }
     }
 
     private void Shoot()
     {
-        // Spawn a bullet and project it the direction the player is aiming
         Bullet bullet = Instantiate(this.bulletPrefab, this.transform.position, this.transform.rotation);
         bullet.Project(this.transform.up);
     }
@@ -118,18 +110,12 @@ private void TurnOnCollisions()
 
     private void OnCollisionEnter2D(Collision2D collision)
     {
-        // Check if the player crashed into an asteroid
         if (collision.gameObject.tag == "Asteroid")
         {
-            // Stop all movement of the ship
-            _rigidbody.velocity = Vector3.zero;
-            _rigidbody.angularVelocity = 0.0f;
-
-            // Stop all player controls and rendering of the ship
+            this.rigidbody.velocity = Vector3.zero;
+            this.rigidbody.angularVelocity = 0.0f;
             this.gameObject.SetActive(false);
 
-            // Inform the game manager the player has died so the lives can be
-            // updated along with any other state changes
             FindObjectOfType<GameManager>().PlayerDeath(this);
         }
     }