diff --git a/src/easystar.js b/src/easystar.js
index 8323066..30ec7c7 100755
--- a/src/easystar.js
+++ b/src/easystar.js
@@ -156,7 +156,9 @@ EasyStar.js = function() {
         if (directionalConditions[y] === undefined) {
             directionalConditions[y] = {};
         }
-        directionalConditions[y][x] = allowedDirections;
+        directionalConditions[y][x] = allowedDirections
+            .map(function(c){return c|0}) // force integer
+            .reduce(function(p,c){return p|c},0);
     };
 
     /**
@@ -468,23 +470,14 @@ EasyStar.js = function() {
     // Helpers
     var isTileWalkable = function(collisionGrid, acceptableTiles, x, y, sourceNode) {
         var directionalCondition = directionalConditions[y] && directionalConditions[y][x];
-        if (directionalCondition) {
+        if (directionalCondition !== undefined) {
             var direction = calculateDirection(sourceNode.x - x, sourceNode.y - y)
-            var directionIncluded = function () {
-                for (var i = 0; i < directionalCondition.length; i++) {
-                    if (directionalCondition[i] === direction) return true
-                }
-                return false
-            }
-            if (!directionIncluded()) return false
-        }
-        for (var i = 0; i < acceptableTiles.length; i++) {
-            if (collisionGrid[y][x] === acceptableTiles[i]) {
-                return true;
-            }
+            return (direction&directionalCondition) > 0;
         }
 
-        return false;
+        return acceptableTiles.indexOf(collisionGrid[y][x]) != -1
+        
+        //return true;
     };
 
     /**
@@ -546,11 +539,11 @@ EasyStar.js = function() {
     };
 }
 
-EasyStar.TOP = 'TOP'
-EasyStar.TOP_RIGHT = 'TOP_RIGHT'
-EasyStar.RIGHT = 'RIGHT'
-EasyStar.BOTTOM_RIGHT = 'BOTTOM_RIGHT'
-EasyStar.BOTTOM = 'BOTTOM'
-EasyStar.BOTTOM_LEFT = 'BOTTOM_LEFT'
-EasyStar.LEFT = 'LEFT'
-EasyStar.TOP_LEFT = 'TOP_LEFT'
+EasyStar.TOP = 1
+EasyStar.TOP_RIGHT = 2
+EasyStar.RIGHT = 4
+EasyStar.BOTTOM_RIGHT = 8
+EasyStar.BOTTOM = 16
+EasyStar.BOTTOM_LEFT = 32
+EasyStar.LEFT = 64
+EasyStar.TOP_LEFT = 128
diff --git a/src/node.js b/src/node.js
index f9756c8..016a1ba 100755
--- a/src/node.js
+++ b/src/node.js
@@ -6,17 +6,19 @@
 * @param {Number} costSoFar How far this node is in moves*cost from the start.
 * @param {Number} simpleDistanceToTarget Manhatten distance to the end point.
 **/
-module.exports = function(parent, x, y, costSoFar, simpleDistanceToTarget) {
+function Node(parent, x, y, costSoFar, simpleDistanceToTarget) {
     this.parent = parent;
     this.x = x;
     this.y = y;
     this.costSoFar = costSoFar;
     this.simpleDistanceToTarget = simpleDistanceToTarget;
+};
 
-    /**
-    * @return {Number} Best guess distance of a cost using this node.
-    **/
-    this.bestGuessDistance = function() {
-        return this.costSoFar + this.simpleDistanceToTarget;
-    }
-};
\ No newline at end of file
+/**
+* @return {Number} Best guess distance of a cost using this node.
+**/
+Node.prototype.bestGuessDistance = function(){
+    return this.costSoFar + this.simpleDistanceToTarget;
+}
+
+module.exports = Node;