boye · February 14, 2014 15:48 · Feb 14, 2014
diff --git a/perfscroll.html b/perfscroll.html
@@ -0,0 +1,56 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <script src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
+  <meta charset="utf-8">
+  <title>Perfscroll jQuery plugin</title>
+</head>
+<body>
+      <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+        <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+      <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+        <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+      <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+        <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+      <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+        <br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+  <script>
+    $(function () {
+
+      // Small plugin to implement a performant scroll listener
+      // Based on an idea by John Resig
+      // @see: http://ejohn.org/blog/learning-from-twitter/
+      $.fn.perfscroll = function (fn, interval) {
+        var didScroll = false,
+            evt = null;
+
+        $(this).on('scroll', function (e) {
+          evt = e;
+          if ( !didScroll ) {
+            didScroll = true;
+          }
+        });
+
+        setInterval($.proxy(function () {
+          if ( didScroll ) {
+            didScroll = false;
+            if ( fn && $.isFunction(fn) ) {
+              fn.apply(this, [evt]);
+            }
+          }
+        }, this), interval || 250);
+
+      };
+
+      // Example
+      $(window).perfscroll(function (e) {
+        console.log(this.scrollTop());
+        // console.log(e); <-- onscroll event object
+        // console.log(this) <-- points to element
+        // ^ this means you can do someting like: if (this.scrollTop()>10) {}
+      });
+
+    });
+  </script>
+</body>
+</html>