Merge branch 'offset-option'

Author: Chris Ferdinandi

README.md

@@ -54,9 +54,10 @@ You can pass options and callbacks into Smooth Scroll through the `init()` funct
 
 ```javascript
 smoothScroll.init({
-	speed: 500, // How fast to complete the scroll in milliseconds
+	speed: 500, // Integer. How fast to complete the scroll in milliseconds
 	easing: 'easeInOutCubic', // Easing pattern to use
 	updateURL: false, // Boolean. Whether or not to update the URL with the anchor hash on scroll
+	offset: 0, // Integer. How far to offset the scrolling anchor location in pixels
 	callbackBefore: function ( toggle, anchor ) {}, // Function to run before scrolling
 	callbackAfter: function ( toggle, anchor ) {} // Function to run after scrolling
 });
@@ -107,6 +108,7 @@ Smooth Scroll also lets you override global settings on a link-by-link basis usi
 <a data-scroll
    data-options="speed: 500;
                  easing: easeInOutCubic;
+                 offset: 0;
                  updateURL: false"
 >
 	Anchor Link
@@ -183,6 +185,8 @@ Smooth Scroll is licensed under the [MIT License](http://gomakethings.com/mit/).
 
 
 ## Changelog
+* v4.5 - March 20, 2014
+	* Added `offset` to `options`
 * v4.4 - March 15, 2014
 	* [Fixed iOS scroll-to-top bug](https://github.com/cferdinandi/smooth-scroll/issues/45).
 * v4.3 - March 5, 2014

index.html

@@ -71,6 +71,7 @@ <h1 style="text-align: center; font-size: 3em;">Smooth Scroll</h1>
 		smoothScroll.init({
 			speed: 500,
 			easing: 'easeInOutCubic',
+			offset: 0,
 			updateURL: false,
 			callbackBefore: function ( toggle, anchor ) {},
 			callbackAfter: function ( toggle, anchor ) {}

smooth-scroll.js

@@ -1,6 +1,6 @@
 /* =============================================================
 
-	Smooth Scroll v4.4
+	Smooth Scroll v4.5
 	Animate scrolling to anchor links, by Chris Ferdinandi.
 	http://gomakethings.com
 
@@ -21,6 +21,7 @@ window.smoothScroll = (function (window, document, undefined) {
 	var _defaults = {
 		speed: 500,
 		easing: 'easeInOutCubic',
+		offset: 0,
 		updateURL: false,
 		callbackBefore: function () {},
 		callbackAfter: function () {}
@@ -116,15 +117,16 @@ window.smoothScroll = (function (window, document, undefined) {
 		// Options and overrides
 		options = _mergeObjects( _defaults, options || {} ); // Merge user options with defaults
 		var overrides = _getDataOptions( toggle ? toggle.getAttribute('data-options') : null );
-		var speed = overrides.speed || options.speed;
+		var speed = parseInt(overrides.speed || options.speed, 10);
 		var easing = overrides.easing || options.easing;
+		var offset = parseInt(overrides.offset || options.offset, 10);
 		var updateURL = overrides.updateURL || options.updateURL;
 
 		// Selectors and variables
 		var fixedHeader = document.querySelector('[data-scroll-header]'); // Get the fixed header
 		var headerHeight = fixedHeader === null ? 0 : (fixedHeader.offsetHeight + fixedHeader.offsetTop); // Get the height of a fixed header if one exists
 		var startLocation = window.pageYOffset; // Current location on the page
-		var endLocation = _getEndLocation( document.querySelector(anchor), headerHeight ); // Scroll to location
+		var endLocation = _getEndLocation( document.querySelector(anchor), headerHeight + offset ); // Scroll to location
 		var animationInterval; // interval timer
 		var distance = endLocation - startLocation; // distance to travel
 		var timeLapsed = 0;