code: function(key, options) {
          var data = options.data;
          if (data === undefined)
              return;
          var array = this._dataIndex[key];
          if (!array || options.replace) {
              array = this._dataIndex[key] = [];
          }
          array.unshift(data);
          array.count = (array.count || 0) + 1;
          while (array.length && array.length > (this.options.maxCellCapacity || 1)) {
              array.pop();
          }
      }
docs: Adds data to the specified canvas position.
  
  @param key
  @param data
  @param replace
  @returns