C# & Game Programming - A…er's Guide (2nd Edition)/Buono 2nd Ed.iso/Chapter3/AsteroidMiner/AsteroidMiner GDI+/AM Arcade.cs

Text File | 2003-04-28 | 20KB | 605 lines

/* AsteroidMiner v2.0 - by Salvatore A. Buono */
using System;
using System.Drawing;
using System.Windows.Forms;
using System.IO; // for file read/write

using GameClasses; // Our common utility class

namespace Games {
  public class AsteroidMiner : System.Windows.Forms.Form {
    // Constants
    const int SCALE = 25;
    const string MEDIA_ROOT = @".\media\";
    const int TIMER_BASE = 40;    // in millis.
    const int MAX_STARS = 20;     // # of stars
    const int MAX_ASTEROIDS = 4;  // # of asteroids (if on)
    const int MAX_MISSILES = 2;   // # of missiles/ship
    const int MISSILE_LIFE = 50;  // 40 ticks
    const int THRUSTER_LIFE = 10; // 10 ticks
    const int ASTEROID_SPEED = 10;// how much they move
    const int GRAVITY_SPEED = 75; // how often gravity affects you
    const int GRAVITY_EFFECT = 5; // how much it effects you
    const int DEFAULT_SPEED = 5;  // default game speed
    const int NUM_LIVES = 5;      // determines when the game is over
    const int SCORE_ASTEROID = 10; // 10 points for hitting an asteroid

    // Image buffer to prevent screen-flicker
    Bitmap offScreenBuffer;

    // Member fields -- UI elements
    private System.Windows.Forms.MainMenu mainMenu1;
    private System.Windows.Forms.MenuItem menuItem1;

    // Member fields
    GameState gameState;  // Holds state information
             Shapes player; // replaces jgp version with drawing

    AnimatedImage[] playerMissiles;
    Shapes[] asteroids;

    Point[] stars;  // background star field

    GameTimer timer;    // Event timer to control all animation
    TimedEvent p1Event; // The player event, for easy reference

    int HighScore = 0;        // Game's top score loads from file
    int p1LastDirection = 0;

    // Main entry-point function
    [STAThread] static void Main() {
      Application.Run(new AsteroidMiner());
    }

    #region Set-up & Initialization
    // Default constructor
    public AsteroidMiner() {
      InitializeComponent();

      gameState = new GameState();

      // Set up timer & timed events
      timer = new GameTimer(TIMER_BASE);
      TimedEvent newEvent;

      // Initialize the two player objects
       player = new Shapes(0);
      player.constraintBox = this.ClientRectangle;

      // Load images into PlayerImageArrays
      player.RescaleImage(SCALE, SCALE);

      // player thruster event
      newEvent = new TimedEvent(THRUSTER_LIFE,
        new TickHandler(PlayerThrust));
      newEvent.payload = player;
      timer.addEvent(newEvent, 1, "player");
      p1Event = newEvent;


      // Initialize the background stars
      Random rnd = new Random();
      stars = new Point[MAX_STARS];
      for (int i = 0; i < MAX_STARS; i++)
        stars[i] = new Point(rnd.Next(ClientSize.Width), rnd.Next(ClientSize.Height));


      // Initialize player's missiles
     playerMissiles = new AnimatedImage[MAX_MISSILES];
      for (int i = 0; i < MAX_MISSILES; i++) {
        playerMissiles[i] = new AnimatedImage(0, 0);
        playerMissiles[i].owner = player;
        playerMissiles[i].constraintBox = this.ClientRectangle;
        playerMissiles[i].RescaleImage(SCALE / 5, SCALE / 5);

        // Set up timer & events
        newEvent = new TimedEvent(MISSILE_LIFE,
          new TickHandler(MoveMissile));
        newEvent.payload = playerMissiles[i];
        timer.addEvent(newEvent, 1, "playerMissile" + i);
      }

      // Initialize the asteroids
      asteroids = new Shapes[MAX_ASTEROIDS];
      for (int i = 0; i < MAX_ASTEROIDS; i++) {
        // Note, there are only 4 image positions so strange
        // things happen when MAX_ASTEROIDS > 4
        asteroids[i] = new Shapes((i % 2 == 1) ? 3 * SCALE :
          20 * SCALE, (i < 2 ? 3 * SCALE : 12 * SCALE));
        asteroids[i].direction = rnd.Next(1, 8);
        asteroids[i].constraintBox = this.ClientRectangle;
        asteroids[i].RescaleImage(2 * SCALE, 2 * SCALE);

        newEvent = new TimedEvent(new TickHandler(MoveAsteroids));
        newEvent.payload = asteroids[i];
        timer.addEvent(newEvent, ASTEROID_SPEED, "asteroid" + i);
        newEvent.isActive = true;
      }

      newEvent = new TimedEvent(new TickHandler(Gravity));
      newEvent.isActive = true;
      timer.addEvent(newEvent, GRAVITY_SPEED, "");

      // Call Invalidate() every tick
      newEvent = new TimedEvent(new TickHandler(ScreenRefresh));
      timer.addEvent(newEvent, 1, "invalidate");
      newEvent.isActive = true;



    }

    // (re) Sets positional data, scores, and other game data
    public void Setup() {
      gameState.currentState = GameState.State.Started;
      gameState.currentSpeed = DEFAULT_SPEED;

      player.imagePosX = 12 * SCALE - (player.imageWidth >> 1);
      player.imagePosY = 8 * SCALE;

                    if (player.score > HighScore)
                        SaveHighScore(player.score);
      HighScore = LoadHighScore();
      if(HighScore < player.score)
       {HighScore = player.score;}
      player.score = 0;


      player.deaths = 0;
      player.isActive = true;
      player.direction = AnimatedImage.NORTH;

      for (int i = 0; i < MAX_MISSILES; i++) {
        playerMissiles[i].isActive = false;
      }

      for (int i = 0; i < MAX_ASTEROIDS; i++) {
        asteroids[i].RescaleImage(2 * SCALE, 2 * SCALE);
        asteroids[i].isActive = true;
      }

      timer.Start();
    }

    // Form's initialize method - we initialize all form related items
    private void InitializeComponent() {
                    this.mainMenu1 = new System.Windows.Forms.MainMenu();
                    this.menuItem1 = new System.Windows.Forms.MenuItem();
                    //
                    // mainMenu1
                    //
                    this.mainMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
                                                                                                                                                                                                                                                                                                                this.menuItem1});
                    //
                    // menuItem1
                    //
                    this.menuItem1.Index = 0;
                    this.menuItem1.Text = "Asteroid Miner";
                    this.menuItem1.Click += new System.EventHandler(this.SinglePlayer_Click);
                    //
                    // AsteroidMiner
                    //
                    this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
                    this.BackColor = System.Drawing.Color.Black;
                    this.ClientSize = new System.Drawing.Size(600, 400);
                    this.Menu = this.mainMenu1;
                    this.Name = "AsteroidMiner";
                    this.Text = "Asteroid Miner";
                    this.Load += new System.EventHandler(this.AsteroidMiner_Load);

                }
    #endregion

    #region Game-play functions
    // Start up the player's thrusters
    public void EngageThrusters(Player player) {
      if (player.isActive) {
        if (player == player)
          p1Event.Reset(); // reset the timer from now

        Utils.PlaySound(MEDIA_ROOT + "Thrust.wav");
      }

      return;
    }

    // Fire a missile (if any available) from the given player
    public void FireMissile(Player player, AnimatedImage[] missiles) {
      if (!player.isActive)
        return;

      for (int i = 0; i < MAX_MISSILES; i++) {
        // shoot the first missile that's not already out there!
        if (!missiles[i].isActive) {
          // set missiles properties so that it will get
          // properly animated
          missiles[i].isActive = true;
          missiles[i].direction = player.direction;
          missiles[i].imagePosX = player.imagePosX;
          missiles[i].imagePosY = player.imagePosY;

          TimedEvent missileEvent = timer.getEvent
            ("playerMissile" + i);
          missileEvent.Reset();

          Utils.PlaySound(MEDIA_ROOT + "Fire.wav");
          break;
        }
      }
    }

    public void ExertGravitationalPull(Player player) {
      if (player.imagePosX != ClientSize.Width >> 1)
        player.imagePosX += (player.imagePosX >
          (ClientSize.Width >> 1)) ? -GRAVITY_EFFECT : GRAVITY_EFFECT;
      if (player.imagePosY != ClientSize.Height >> 1)
        player.imagePosY += (player.imagePosY >
          (ClientSize.Height >> 1)) ? -GRAVITY_EFFECT : GRAVITY_EFFECT;
    }
    #endregion

    #region Collision Detection Routines
    // Ships can run into the asteroids and missiles.
    // We'll assume that the missiles will detect their collisions
    // so we only have to worry about the others.
    public bool CheckShipCollision(Player player) {
      Player opponent = player;

      // Asteroid collision?
      for (int i = 0; i < MAX_ASTEROIDS; i++) {
        if (asteroids[i].isActive) {
          if (asteroids[i].Intersects(player)) {
            ShipCollided(player);
            return true;
          }
        }
      }

      return false;
    }

    // Asteroids can run into ships & missiles. We'll assume that
    // missiles will detect their collisions themselves since they
    // update frequently.
    public bool CheckAsteroidCollision() {
      for (int i = 0; i < MAX_ASTEROIDS; i++) {
        if (asteroids[i].isActive) {
          if (asteroids[i].Intersects(player)) {
            ShipCollided(player);
            return true;
          }
        }
      }

      return false;
    }

    // Missiles can only run into asteroids.
    public bool CheckMissileCollision(AnimatedImage missile) {
      if (missile.isActive) {
        for (int i = 0; i < MAX_ASTEROIDS; i++) {
          if (missile.Intersects(asteroids[i])) {
            AsteroidCollided(asteroids[i]);
            missile.isActive = false;
            Utils.PlaySound(MEDIA_ROOT + "Hit.wav");
            return true;
          }
        }
      }

      return false;  // Must not have hit anything!
    }

    // The ship ran into something! Add to the death count and
    // end the game if we're out of lives.
    public void ShipCollided(Player victim) {
      if (!victim.isActive)
        return; // He's already dead!

      victim.isActive = false;
      victim.direction = 0; // index of our explosion image
      Utils.PlaySound(MEDIA_ROOT + "Hit.wav");

      victim.deaths++;

      if(victim.deaths >= NUM_LIVES) {
        gameState.currentState = GameState.State.Stopped;

        if (victim.score > HighScore) {
          SaveHighScore(victim.score);
        }
      }
    }

    // The asteroid was hit! Cycle through its different scaled
    // display & increment the player's score.
    public void AsteroidCollided(AnimatedImage victim) {
      int scaleFactor = (victim.imageWidth <= (SCALE / 2)) ?
        SCALE * 2 : victim.imageWidth / 2;
      victim.RescaleImage(scaleFactor, scaleFactor);

      player.score += SCORE_ASTEROID;
    }
    #endregion

            #region OnPaint
            protected override void OnPaint(PaintEventArgs e)
            {
                Graphics gOffScreen;     // Graphics context for offscreen buffer
                Graphics g = e.Graphics; // Screen's graphics object

                // If the size of the window has changed, we need a new buffer
                if (offScreenBuffer == null ||
                    offScreenBuffer.Width != this.ClientSize.Width ||
                    offScreenBuffer.Height != this.ClientSize.Height)
                {
                    if (ClientSize.Width == 0 || ClientSize.Height == 0)
                        return;
                    offScreenBuffer = new Bitmap(this.ClientSize.Width,
                        this.ClientSize.Height);
                }

                // We paint just as if it were the screen. The function need not
                // know it is being buffered.
                gOffScreen = Graphics.FromImage(offScreenBuffer);
                DoPaint(gOffScreen);   // Call normal paint method
                gOffScreen.Dispose();  // Free up resources right away

                // We draw our buffered image onto the screen in one operation.
                // This could be improved further still by using clip regions.
                g.DrawImage(offScreenBuffer, 0, 0);
            }

            public void DoPaint(Graphics g)
            {
                // Redraw the background
                g.FillRectangle(Brushes.Black, 0, 0,
                    this.Size.Width, this.Size.Height);

                // Write start-up text if game is stopped
                if (gameState.currentState == GameState.State.Stopped)
                {
                    Brush YellowBrush = Brushes.Yellow;
                    Font LargeAlgerianFont = new Font("Algerian", 24);
                    Font MidAlgerianFont = new Font("Algerian", 18);

                    g.DrawString("C# and Game Programming", LargeAlgerianFont, YellowBrush, 2 * SCALE, SCALE);
                    g.DrawString("A Beginner's Guide", LargeAlgerianFont, YellowBrush, 9 * SCALE, 5 * SCALE);
                    g.DrawString("By Salvatore A. Buono", MidAlgerianFont, YellowBrush, 2 * SCALE, 14 * SCALE);
                }
                else
                {    Font Normal = new Font("Time New Roman", 14, FontStyle.Bold);
                    // Draw the scores
                    if(player.score < HighScore)
                    {g.DrawString(HighScore.ToString(), Normal, Brushes.Blue,
                            4 * SCALE, SCALE);}
                    else
                    {    g.DrawString(player.score.ToString(), Normal, Brushes.Blue,
                        4 * SCALE, SCALE);}

                    g.DrawString(player.score.ToString(), Normal,  Brushes.Blue,
                        16 * SCALE, SCALE);

                    // Draw the stars
                    for(int i = 0; i < MAX_STARS; i++)
                        g.FillEllipse(Brushes.OrangeRed, stars[i].X, stars[i].Y, 5, 5);

                    // Draw player 1 & its appropriate exhaust
                    if(player.isActive == true)
                    {
                        g.DrawPie(Pens.Blue, player.imagePosX, player.imagePosY,
                            SCALE, SCALE, player.startAngle(), 50);
                        if (p1Event.isActive)
                        {
                            player.Exhuast(g, Brushes.Aqua);
                        }
                    }

                    // Draw missiles
                    for (int i = 0; i < MAX_MISSILES; i ++)
                    {
                        if (playerMissiles[i].isActive)
                            g.FillEllipse(Brushes.Blue, playerMissiles[i].imagePosX,
                                playerMissiles[i].imagePosY, 5, 5);
                    }

                    // Draw asteroids
                    asteroids[0].Asteroid(g, Brushes.Red);
                    asteroids[1].Asteroid(g, Brushes.Blue);
                    asteroids[2].Asteroid(g, Brushes.Orange);
                    asteroids[3].Asteroid(g, Brushes.Yellow);
                }
            }
    #endregion

    #region OnKey
    protected override void OnKeyDown(KeyEventArgs e) {
      if (gameState.currentState != GameState.State.Started)
        return;

      // Player controls
      switch(e.KeyCode) {
        case Keys.Up:
          p1LastDirection = player.direction;
          EngageThrusters(player);
          break;
        case Keys.Left:
          if (player.isActive)
            player.RotateDirection(1);
          break;
        case Keys.Right:
          if (player.isActive)
            player.RotateDirection(-1);
          break;
        case Keys.Down:
          if (!player.isActive)
            player.isActive = true;
          player.RandomizePosition();
          break;
        case Keys.NumPad0:
        case Keys.Space:
          FireMissile(player, playerMissiles);
          break;

        // Exit game
        case Keys.Escape:
          ExitApplication();
          break;
      }
      base.OnKeyDown(e);
    }
    #endregion

    #region TimedEvent Tick Handlers
    // Implements the player's thruster push. Called repetitively until
    // the timer counts down to 0.
    public void PlayerThrust(TimedEvent e, Object obj) {
      if (gameState.currentState == GameState.State.Stopped) {
        e.isActive = false;
        return;
      }

      Player player = (Player) obj;
      int tempDir = player.direction;

      player.direction = p1LastDirection;
      player.Animate();
      player.Animate();
      player.direction = tempDir;
      player.WrapInBox();

      CheckShipCollision(player);
    }

    // Implements the missile's movement. Called automatically until
    // the timer counts down to 0.
    public void MoveMissile(TimedEvent e, Object obj) {
      if (gameState.currentState == GameState.State.Stopped) {
        e.isActive = false;
        return;
      }

      // Get a proper missile object from the event
      AnimatedImage missile = (AnimatedImage) obj;
      for(int i = 0; i < gameState.currentSpeed; i++) {
        missile.Animate();
        missile.WrapInBox();

        // See if we hit anything!
        CheckMissileCollision(missile);
      }

      // disable the missile so it can be fired again
      if (e.tickCounter <= 1)
        missile.isActive = false;
    }

    // Implements the asteroid's random movement. This is called
    // continously throughout the game.
    public void MoveAsteroids(TimedEvent e, Object obj) {
      if (gameState.currentState == GameState.State.Stopped) {
        e.isActive = false;
        return;
      }

      Random rnd = new Random();
      for(int i = 0; i < MAX_ASTEROIDS; i++) {
        if (rnd.Next(10) > 7) // Change the direction ~70% of the time
          asteroids[i].direction = rnd.Next(1, 8);
        asteroids[i].Animate();
        asteroids[i].WrapInBox();
        CheckAsteroidCollision();
      }
    }

    // Implements the gravity (from an unseen field -- that only
    // affects ships -- located at the center of the screen).
    public void Gravity(TimedEvent e, Object obj) {
      if (gameState.currentState == GameState.State.Stopped) {
        e.isActive = false;
        return;
      }

      if (player.isActive){ // Doesn't pull "dead" ships
        ExertGravitationalPull(player);
        CheckShipCollision(player);
      }

      Utils.PlaySound(MEDIA_ROOT + "Gravity.wav");
    }

    // Regular refresh function. The screen will redraw every tick.
    public void ScreenRefresh(TimedEvent e, Object obj) {Invalidate();}
    #endregion

    #region Menu Click Handler
    private void SinglePlayer_Click(object sender, System.EventArgs e) {
      gameState.currentMode = GameState.Mode.SinglePlayer;
      Setup();
    }
    #endregion

    #region File Read/Write
    // Utility function to read the high score from a file
    public int LoadHighScore() {
      StreamReader file;
      string strTemp = "";
      int score = 0;

      try {
        file = new StreamReader(@".\HighScore.txt");
        for (int i = 0; i < 4; i++)
          strTemp = file.ReadLine();
        score = int.Parse(strTemp.Substring(0, strTemp.IndexOf("\t")));
        file.Close();
      } catch (Exception e) {Console.WriteLine(e);}

      return score;
    }

    // Utility function to write the high score from a file
    public void SaveHighScore(int score) {
      StreamWriter file;

      try {
        file = new StreamWriter(@".\HighScore.txt");
        file.WriteLine("Asteroid Miner High Scores");
        file.WriteLine("--------------------------");
        file.WriteLine();
        file.WriteLine(score + "\t" + DateTime.Now);
        file.Flush();
        file.Close();
      } catch (Exception e) {Console.WriteLine(e);}
    }
    #endregion

    // Clean exit function
    public void ExitApplication() {
      if (MessageBox.Show ("Are you sure you want to quit?", "End Game",
          MessageBoxButtons.YesNo) == DialogResult.Yes)
        Application.Exit();
    }

    // The default Invalidate clears the entire screen creating a very
    // undesireable flicker. This override allows the paint method to
    // control it's redraw.
    public new void Invalidate() {
      OnPaint(new PaintEventArgs(Graphics.FromHwnd(this.Handle),
        new Rectangle(new Point(0, 0), this.Size)));
    }

    // The system occasionally also calls OnPaintBackground which will
    // mean the screen will be cleared, painted with the background
    // color, then repainted. This is another cause of flicker, so we
    // just override it and tell it not to do anything!
    protected override void OnPaintBackground(PaintEventArgs e) {
      // Do nothing!
    }

            private void AsteroidMiner_Load(object sender, System.EventArgs e)
            {

            }
  }
}