code: function (callback, scope) {
          var coords = _.isFunction(callback) && this.current();
  
          this.position = 0;
          this.iteration = 0;
  
          // send before and after values to the callback
          return coords && callback.call(scope || this, null, this.current(), coords);
      }
docs: Set everything to minimum dimension
  
  @param {Function} [callback] - receives `(err:Error, coords:Object, previous:Object)`
  @param {Object} [scope]