function Map(width, height) {
      if (width === void 0) {
        width = DEFAULT_WIDTH;
      }
      if (height === void 0) {
        height = DEFAULT_HEIGHT;
      }
      this._width = width;
      this._height = height;
    }
@class Base map generator
@param {int} [width=ROT.DEFAULT_WIDTH]
@param {int} [height=ROT.DEFAULT_HEIGHT]