From fa51f455fe716fe2a65c7dfed8b10184ad917847 Mon Sep 17 00:00:00 2001
From: Hyunje Alex Jun <me@noraesae.net>
Date: Tue, 28 Jan 2014 14:51:53 +0900
Subject: [PATCH] Avoid the 'divide by zero' problem in bindMobileTouchHandler.

---
 src/perfect-scrollbar.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/perfect-scrollbar.js b/src/perfect-scrollbar.js
index 94f5993..e4650cd 100644
--- a/src/perfect-scrollbar.js
+++ b/src/perfect-scrollbar.js
@@ -462,9 +462,13 @@
             startCoords = currentCoords;
 
             var currentTime = (new Date()).getTime();
-            speed.x = differenceX / (currentTime - startTime);
-            speed.y = differenceY / (currentTime - startTime);
-            startTime = currentTime;
+
+            var timeGap = currentTime - startTime;
+            if (timeGap > 0) {
+              speed.x = differenceX / timeGap;
+              speed.y = differenceY / timeGap;
+              startTime = currentTime;
+            }
 
             e.preventDefault();
           }