diff --git a/dist/Triangulate.js b/dist/Triangulate.js
index df3f636..ee225ec 100644
--- a/dist/Triangulate.js
+++ b/dist/Triangulate.js
@@ -1245,6 +1245,12 @@ var Triangulate = {};
     }
   };
 
+  function isClockWise(ring) {
+    return 0 < ring.reduce(function(a, b, c, d) {
+      return a + ((c < d.length - 1) ? (d[c+1][0] - b[0]) * (d[c+1][1] + b[1]) : 0);
+    }, 0);
+  }
+
   function process(res, id, properties, geom, position, color) {
     var geometry = transform(geom, position),
       bbox = getBBox(geometry[0]),
diff --git a/package.json b/package.json
index 5a8cae0..d6b3484 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "Triangulate",
-  "version": "0.1.2",
+  "version": "0.1.3",
   "homepage": "http://osmbuildings.org",
   "description": "GeoJSON triangulation scripts collection. Mainly used for OSM Buildings backend + frontend.",
   "main": "dist/Triangulate.js",
diff --git a/src/Triangulate.js b/src/Triangulate.js
index 086986d..33cc605 100644
--- a/src/Triangulate.js
+++ b/src/Triangulate.js
@@ -96,6 +96,12 @@ var Triangulate = {};
     }
   };
 
+  function isClockWise(ring) {
+    return 0 < ring.reduce(function(a, b, c, d) {
+      return a + ((c < d.length - 1) ? (d[c+1][0] - b[0]) * (d[c+1][1] + b[1]) : 0);
+    }, 0);
+  }
+
   function process(res, id, properties, geom, position, color) {
     var geometry = transform(geom, position),
       bbox = getBBox(geometry[0]),