retina.js is an open source script that makes it easy to serve
high-resolution images to devices with retina displays
When your users load a page, retina.js checks each image on the page to see if there is a high-resolution version of that image on your server. If a high-resolution variant exists, the script will swap in that image in-place.
The script assumes you use Apple's prescribed high-resolution modifier (@2x) to denote high-resolution image variants on your server.
For example, if you have an image on your page that looks like this:
<img src="/images/my_image.png" />
The script will check your server to see if an alternative image exists at this path:
"/images/my_image@2x.png"
The JavaScript helper script automatically replaces images on your page with high-resolution variants (if they exist). To use it, download the script and include it at the bottom of your page.
retina.js file on your server<script type="text/javascript" src="/scripts/retina.js"></script>
</body> tag)
The LESS CSS mixin is a helper for applying high-resolution background images in your stylesheet. You provide it with an image path and the dimensions of the original-resolution image. The mixin creates a media query specifically for Retina displays, changes the background image for the selector elements to use the high-resolution (@2x) variant and applies a background-size of the original image in order to maintain proper dimensions. To use it, download the mixin, import or include it in your LESS stylesheet, and apply it to elements of your choice.
Syntax:
.at2x(@path, [optional] @width: auto, [optional] @height: auto);
.at2x() mixin from retina.less to your LESS stylesheet.at2x() mixin anywhere instead of using background-image
#logo {
.at2x('/images/my_image.png', 200px, 100px);
}
#logo {
background-image: url('/images/my_image.png');
}
@media all and (-webkit-min-device-pixel-ratio: 1.5) {
#logo {
background-image: url('/images/my_image@2x.png');
background-size: 200px 100px;
}
}
We'd love your help. Fork us so we can make retina graphics easier for everyone.
Made with love in Boulder, CO by imulus
Thanks to Zach Dischner for the kickass background photo. Check out his work on Flickr.