code: function(x, y, options) {
          var maskX = this._getMaskX(x);
          var maskY = this._getMaskY(y);
          var key = this._getIndexKey(maskX, maskY);
          return this._addDataToIndex(key, options);
      }
docs: Sets data in the specified position on the canvas.
  
  @param x
  @param y
  @param options.data
  a data object to set