   @name afterAdd
   @methodOf Engine#
   @event
-
   @param {GameObject} object The object that has just been added to the
   engine.
   ###

  @name beforeDraw
  @methodOf Engine#
  @event

  @params {PowerCanvas} canvas A reference to the canvas to draw on.
  ###


  @name overlay
  @methodOf Engine#
  @event
  @params {PowerCanvas} canvas A reference to the canvas to draw on. 
  ###

