 
   delete: ->
     @gone = true
-    if @sprite?
-      @sprite.delete()
-      @sprite = null
+    @sprite?.delete()
+    @sprite = null
 
 class Game
   constructor: (@engine) ->

      @createMeteor()

    @meteor_interval -= dt * 0.01

    for obj_list in [@stars, @meteors]
      for obj in obj_list

    @meteor_interval = 0.3
    @next_meteor_at = @meteor_interval

    @star_interval = 0.1
    @next_star_at = @star_interval

    @garbage_interval = 10
    @next_garbage_at = @garbage_interval

    @score = 0

  start: ->
    @engine.on('draw', @draw)
    @engine.on('update', @update)
    @engine.start()

  garbageCollect: ->
    @stars = (star for star in @stars when not star.gone)
    @meteors = (meteor for meteor in @meteors when not meteor.gone)

  createStar: ->
    sprite = new Sprite @img_star[randInt(0, 1)],
      batch: @batch
      pos: new Vec2d(@engine.size.x, randInt(0, @engine.size.y))
