Added a simple vertical test case.
Added a simple vertical test case.

--- /dev/null
+++ b/test-verticaledge.py
@@ -1,1 +1,37 @@
+#!/usr/bin/python
 
+from voronoi import *
+import cv2,cv
+import numpy
+import random
+import time
+
+# Config 
+width=500
+height=500
+
+# Init open CV
+cv.NamedWindow('testwin')
+
+img = numpy.zeros((height,width, 1), numpy.uint8)
+
+# Voronoi
+points=[(50,50),
+        (100,50)]
+    
+for p in points:
+    print 'point',p
+    cv2.circle(img,(int(p[0]),int(p[1])),2,255,-1)
+cv2.imshow("testwin",img)
+
+v=Voronoi(points,width,height)
+v.img=img
+edges=v.edges()
+for edge in edges:
+    cv2.line(img,edge[0],edge[1],255)
+
+
+# Show results
+cv2.imshow("testwin",img)
+cv2.waitKey(0)
+