Modify readme to reflect updates

markdalgleish · markdalgleish · commit ece21d319b7b · 2013-01-23T08:23:45.000+11:00
diff --git a/README.md b/README.md
@@ -33,7 +33,7 @@ This will look for any parallax backgrounds or elements within the specified ele
 
 Support in Mobile WebKit browsers requires a touch scrolling library, and a slightly tweaked configuration. For a full walkthrough on how to implement this correctly, read my blog post ["Mobile Parallax with Stellar.js"](http://markdalgleish.com/2012/10/mobile-parallax-with-stellar-js).
 
-Please note that parallax backgrounds are not recommended in Mobile WebKit, only parallax elements.
+Please note that parallax backgrounds are not recommended in Mobile WebKit due to performance constraints. Instead, use parallax elements with static backgrounds.
 
 ## Parallax Elements
 
@@ -183,18 +183,11 @@ If your method for creating a scrolling interface isn't covered by one of these,
 
 ``` js
 $.stellar.scrollProperty.margin = {
-  getTop: function($element) {
-    return parseInt($element.css('margin-top'), 10) * -1;
-  },
-  setTop: function($element, val) {
-    $element.css('margin-top', val);
-  },
-
   getLeft: function($element) {
     return parseInt($element.css('margin-left'), 10) * -1;
   },
-  setLeft: function($element, val) {
-    $element.css('margin-left', val);
+  getTop: function($element) {
+    return parseInt($element.css('margin-top'), 10) * -1;
   }
 }
 ```
@@ -232,6 +225,27 @@ $.stellar({
 });
 ```
 
+If, for technical reasons, you need to set both properties at once, you can define a single 'setPosition' function:
+
+``` js
+$.stellar.positionProperty.foobar = {
+  setPosition: function($element, newLeft, originalLeft, newTop, originalTop) {
+    $element.css('transform', 'translate3d(' +
+      (newLeft - originalLeft) + 'px, ' +
+      (newTop - originalTop) + 'px, ' +
+      '0)');
+  }
+}
+```
+
+Now, you can specify this position property in Stellar.js' configuration.
+
+``` js
+$.stellar({
+  positionProperty: 'foobar'
+});
+```
+
 ## Package Managers
 
 Stellar.js can be installed with the following tools.
@@ -266,29 +280,29 @@ I'm sure there are heaps more. [Let me know if you'd like me to feature your sit
 
 ## How to Build
 
-Stellar.js uses [Grunt](http://gruntjs.com) and [PhantomJS](http://phantomjs.org/).
-
-Once you've got Grunt and PhantomJS set up, you can validate, test, concatenate and minify the project with the following command:
+Stellar.js uses [Node.js](nodejs.org), [Grunt](http://gruntjs.com) and [PhantomJS](http://phantomjs.org/).
 
-`grunt`
+Once you've got Node and PhantomJS set up, install the dependencies:
 
-Each of the build steps are also available individually.
+`$ npm install`
 
-To test the code using QUnit and PhantomJS:
+To lint, test and minify the project, simply run the following command:
 
-`grunt qunit`
+`$ grunt`
 
-To validate the code using JSHint:
+Each of the build steps are also available individually.
 
-`grunt lint`
+`$ grunt test` to test the code using QUnit and PhantomJS: 
 
-To continuously validate and test the code while developing:
+`$ grunt lint` to validate the code using JSHint.
 
-`grunt watch`
+`$ grunt watch` to continuously lint and test the code while developing.
 
 ## Contributing to Stellar.js
 
-Make sure that all plugin changes are made in `src/jquery.stellar.js` (`/jquery.stellar.js` and `/jquery.stellar.min.js` are generated by Grunt), and that you successfully test and build the project with `grunt` before committing.
+Ensure that you successfully test and build the project with `$ grunt` before committing.
+
+Make sure that all plugin changes are made in `src/jquery.stellar.js` (`/jquery.stellar.js` and `/jquery.stellar.min.js` are generated by Grunt).
 
 If you want to contribute in a way that changes the API, please file an issue before submitting a pull request so we can discuss how to appropriately integrate your ideas.
 
