text: var BiAStarFinder = require('./BiAStarFinder');
  
  /**
   * Bi-direcitional Best-First-Search path-finder.
   * @constructor
   * @extends BiAStarFinder
   * @param {object} opt
   * @param {boolean} opt.allowDiagonal Whether diagonal movement is allowed.
   * @param {function} opt.heuristic Heuristic function to estimate the distance
   *     (defaults to manhattan).
   */
  function BiBestFirstFinder(opt) {
      BiAStarFinder.call(this, opt);
  
      var orig = this.heuristic;
      this.heuristic = function(dx, dy) {
          return orig(dx, dy) * 1000000;
      };
  }
  
  BiBestFirstFinder.prototype = new BiAStarFinder();
  BiBestFirstFinder.prototype.constructor = BiBestFirstFinder;
  
  module.exports = BiBestFirstFinder;
  