LESS mixin for retina images. ( _2x image for retina devices ). Direct port of https://gist.github.com/rakeshjuyal/0b2c614ca987a1f04ded

retinafy.less

/*
Direct port of https://gist.github.com/rakeshjuyal/0b2c614ca987a1f04ded
Converted scss mixin to less.
*/
.retinafy(@file, @type : png, @width : auto, @height : auto, @suffix : _2x) {
  background-image: url("@{file}.@{type}");

  @media (min--moz-device-pixel-ratio: 1.3),
         (-o-min-device-pixel-ratio: 2.6/2),
         (-webkit-min-device-pixel-ratio: 1.3),
         (min-device-pixel-ratio: 1.3),
         (min-resolution: 1.3dppx) {

        background-image: url("@{file}@{suffix}.@{type}");
        background-size: @width @height;

  }
}

/* Example */
.glass {
    .retinafy( '/images/glass' , png , auto , 16px );
}