Game Code

/////////////////////////////////////////////////////////////////////////
// Title    : Space Invaders - playerController.cs
// Author   :
// Date     :
//////////////////////////////////////////////////////////////////////////

//////////////////////////////////////////////////////////////////////////
// Pre-Processor Directives
//////////////////////////////////////////////////////////////////////////
using UnityEngine;

public class playerController : MonoBehaviour
{

    /*          CONSTS          */
    const float CONST_PLAYER_Y = 3.0f;
    const float PLAYER_X_SPEED = 0.030F;
    const float MISSILE_Y_MAX = 14f;
    const float MISSILE_Y_SPAWN = 3.1F;
    const float MISSILE_X_MAX = -0.11f;
    const float MISSILE_VELOCITY = 0.025f;


    /*          PLAYER VARS             */
    public GameObject Player;
    public int Player_Lives;
    Vector2 Player_Spawn;
    Vector3 Player_Transform;
    float Player_X;
    bool HashHitEnemy;
    public bool HasFired;


    /*          MISSILE VARS            */
    public GameObject Missile;
    Vector2 Missile_Dynamic_Spawn;
    Vector2 MISSILE_FIXED_SPAWN = new Vector2(0f, 3.1f);
    float Missile_X_Position;
    float Missile_Y_Position;
    Vector3 Missile_Transform;

    /// <summary>
    /// Global variables
    ///
    /// * default y position of the player (to prevent movement up the screen)
    /// * default x position of the missile (to snap its coordinates to the player)
    /// * new x position of the missile (as the player updates)
    /// * transform component of the missile
    /// * how far up the missile fires to
    /// * true/false for if the player has shot anything
    /// * lives of the player
    /// </summary>

    // Use this for initialization
    void Start ()
    {
        Player_Spawn = new Vector2(-0.11F, CONST_PLAYER_Y);
        Missile_Dynamic_Spawn = new Vector2(0f, 3.1f);
        Missile_Y_Position = Missile_Dynamic_Spawn.y;
        Player_Lives = 3;
        HashHitEnemy = false;
        HasFired = false;

        Set_Player_Spawn();
    }

    // Update is called once per frame
    // Controls for player movement and ability to fire a missile
    void Update ()
    {
        #region User Input
        if (Input.GetKey(KeyCode.A))
        {
            Player_X -= PLAYER_X_SPEED;
        }
        else if (Input.GetKey(KeyCode.D))
        {
            Player_X += PLAYER_X_SPEED;
        }
        else if (Input.GetKeyDown(KeyCode.Space))
        {
            if (HasFired == false)
            {
                HasFired = true;
                Create_New_Missile_Spawn();
                Apply_New_Missile_Spawn();
            }
        }
        #endregion

        if (HasFired == true && Missile.transform.position.y < MISSILE_Y_MAX)
        {
            Missile_Y_Position += MISSILE_VELOCITY;
            Missile.transform.position = new Vector3(Missile.transform.position.x, Missile_Y_Position, 0F);
        }
        else
        {
            HasFired = false;
            Missile.transform.position = Missile_Dynamic_Spawn;
        }

        Player.transform.position = new Vector3(Player_X, CONST_PLAYER_Y, 0F);
    }

    private void Create_New_Missile_Spawn()
    {
        Missile_Dynamic_Spawn = new Vector2(Player_X, MISSILE_Y_SPAWN);
    }

    private void Apply_New_Missile_Spawn()
    {

        Missile.transform.position = Missile_Dynamic_Spawn;
    }

    private void Set_Player_Spawn()
    {
        Player.transform.position = Player_Spawn;
    }
}