gistfile1.js

var app = new PLAYGROUND.Application({

  preload: function() {

    /* this is called before create and lets you silently load some assets */

    this.loadData("objects/buildings", "objects/subObjects", "objects/townBuildingList");

  },

  create: function() {

    /* this is called when preloader has finished */

    var buildings = this.data["objects/buildings"];

    for (var i = 0, len = buildings.length; i < len; i++) {
      
      var building = building[i];

      this.loadImages(building.imagePath + building.fileExtension);
      
    }

  },

  ready: function() {

    /* this is called when loader has finished */

  }

});