Awesome

before-after.js

A simple and responsive image comparison slider

Comparison sliders are nothing new. There are even pure CSS implementations that is nothing but short of amazing. However, I wasn’t able to find a truly responsive one that was simple enough for our needs. This gave me the chance (and excuse) to build one myself that can be used anywhere.

The Medium article details each decision made along the way.

DEMO

Image comparison

UPDATES

Performance improvements (Feb, 2017)
before-after is now a jquery plugin, special thanks to @ramblex. Also CDN links updated and fixed a few issues.(Feb, 2016)
I was finally able to remove the jQuery Mobile dependency and handle it with native events. If you wish to help, mobile testing is much appreciated since I can only test a limited number devices. (March, 2015)

DEPENDENCIES

jQuery for ease

USAGE

$('.ba-slider').beforeAfter();

Or you can simply copy the contents of the sample.html to your own page. All links are called from a CDN.

Multiple sliders on the same page

$('.ba-slider').each(function(){
     $(this).beforeAfter();
});

Use with Drupal Behaviors

(function ($, Drupal) { 
Drupal.behaviors.pronatura_image_comparison = { 
  attach: function (context, settings) {        
    $('.ba-slider').each(function(){            
      $(this).beforeAfter();                    
    });                 
  }                     
};                      
})(jQuery, Drupal);