diff --git a/lib/utils/math.js b/lib/utils/math.js
index ea12c9e..e4f3572 100644
--- a/lib/utils/math.js
+++ b/lib/utils/math.js
@@ -1,29 +1,31 @@
 define(function () {
-  return {
-    distance: function distance(a, b) {
-      return Math.pow(a.x - b.x, 2) + Math.pow(a.y - b.y, 2);
-    },
+  var self = {};
 
-    distancePoint: function distancePoint(a, b) {
-      return Math.sqrt(distance(a, b));
-    },
-
-    distanceLink: function distanceLink(p, a, b) {
-      /* http://stackoverflow.com/questions/849211 */
-      var l2 = distance(a, b);
-      if (l2 === 0) {
-        return distance(p, a);
-      }
-      var t = ((p.x - a.x) * (b.x - a.x) + (p.y - a.y) * (b.y - a.y)) / l2;
-      if (t < 0) {
-        return distance(p, a);
-      } else if (t > 1) {
-        return distance(p, b);
-      }
-      return distancePoint(p, {
-        x: a.x + t * (b.x - a.x),
-        y: a.y + t * (b.y - a.y)
-      });
-    }
+  self.distance = function distance(a, b) {
+    return Math.pow(a.x - b.x, 2) + Math.pow(a.y - b.y, 2);
   };
+
+  self.distancePoint = function distancePoint(a, b) {
+    return Math.sqrt(self.distance(a, b));
+  };
+
+  self.distanceLink = function distanceLink(p, a, b) {
+    /* http://stackoverflow.com/questions/849211 */
+    var l2 = self.distance(a, b);
+    if (l2 === 0) {
+      return self.distance(p, a);
+    }
+    var t = ((p.x - a.x) * (b.x - a.x) + (p.y - a.y) * (b.y - a.y)) / l2;
+    if (t < 0) {
+      return self.distance(p, a);
+    } else if (t > 1) {
+      return self.distance(p, b);
+    }
+    return self.distancePoint(p, {
+      x: a.x + t * (b.x - a.x),
+      y: a.y + t * (b.y - a.y)
+    });
+  };
+
+  return self;
 });