zombie game in Diggy?

left4defense.js

(function() {

  var SCREEN_WIDTH = 480,
    SCREEN_HEIGHT = 360,
    SPRITE_SIZE = 24,
    TILE_SIZE = 24,
    TILES_WIDTH = 20,
    TILES_HEIGHT = 15;

  var game,
    map,
    screens;

  var init = function() {

    // Setup DGE
    DGE.set('stage', 'l4d');
    DGE.set('default-dims', TILE_SIZE, TILE_SIZE);
    DGE.set('tile-dims', TILE_SIZE);

    DGE.init({
      base : 'img/',
      stage : 'l4d'
    });

/*
    screens = new DGE.Screens({},
      'battle'
    );
*/

//    screens.battle.init(function() {

      // Initialize the map Sprite
      map.sprite = new DGE.Sprite({
//        addTo : this,
        width : (TILES_WIDTH * TILE_SIZE),
        height : (TILES_HEIGHT * TILE_SIZE)
      });

//    });

//    screens.battle.init();

    // Begin the DGE main game loop
    DGE.main.start();

    // TODO - get rid of this, find a more elegant way
//    screens.battle.show();
    map.init();
    newGame();
    // /TODO

  };

  var map = {
    init : function() {

      // Make the new tile map
      this.tiles = DGE.sprites.tileMap(DGE.Sprite, TILES_WIDTH, TILES_HEIGHT, {
        //addTo : this.sprite,
        group : 'tiles',
        image : 'concrete.png',
        width : SPRITE_SIZE,
        height : SPRITE_SIZE
      });

    },
    load : function(num) {

      var freeCoords = [],
        i,
        m = L4D.maps[num],
        tile, x, y;

      for (y = 0; y < TILES_HEIGHT; y++) {
        for (x = 0; x < TILES_WIDTH; x++) {
          tile = m.data[y][x];
          this.tiles[y][x].image(L4D.tiles[tile]);
          if (tile == 'o') freeCoords.push({
            tx : x,
            ty : y,
          });
        }
      }

      this.survivors = [];

      for (i = 0; i < m.survivors; i++) {
        this.survivors.push(new Survivor({
          txy : freeCoords.shift()
        }));
      };

      this.numSurvivors = this.survivors.length;
      this.zombies = [];

      for (i = 0; i < m.zombies; i++) {
        this.zombies.push(new Zombie({
          tx : DGE.rand(m.spawn.tx1, m.spawn.tx2),
          ty : DGE.rand(m.spawn.ty1, m.spawn.ty2)
        }));
      }

      this.numZombies = this.zombies.length;

// TODO clean this up, get it into main()
setInterval(function() {

  map.zombies.sort(function(a, b) {
    return (a.y - b.y);
  });

  for (var i = 0; i < map.numZombies; i++) {
    map.zombies[i].front();
  }

}, 100);

    }
  };

  var newGame = function() {
    map.load(0);
  };

  var Survivor = DGE.extend(DGE.Sprite, function(conf) {

    this.init(conf, {
      group : 'survivors',
      image : 'zoey_d.gif'
    });

  });

  var Zombie = DGE.extend(DGE.Sprite, function(conf) {

    this.init(conf, {
      group : 'zombies',
      image : 'zombie_u.gif',
      move : DGE.move.angle,
      ping : function() {

        if (DGE.rand(0, 50) == 1) {

          var survivor = map.survivors[DGE.rand(0, (map.survivors.length - 1))];

          this.speed(DGE.rand(1, 3) / 8);
          this.angleTo(survivor, true);

        }

      }
    });

  });

  var zombies = {
    getSpeed : function() {

      var p = DGE.rand(1, 100),
        speed;

      if (p < 50) {
        speed = DGE.rand(1, 5) / DGE.rand(2, 10);
      } else if (p < 80) {
        speed = 1;
      } else if (p < 90) {
        speed = DGE.rand(1, 5) / DGE.rand(1, 2);
      } else {
        speed = DGE.rand(1, 5) / DGE.rand(8, 10);
      }

      return speed;

    }
  };

  init();

})();