Easy retina-ready images using SASS + Compass

gistfile1.sass

=background-2x($background, $file: 'png')
  $image: #{$background+"."+$file}
  $image2x: #{$background+"@2x."+$file}
  
  background: image-url($image) no-repeat
  @media (min--moz-device-pixel-ratio: 1.3),(-o-min-device-pixel-ratio: 2.6/2),(-webkit-min-device-pixel-ratio: 1.3),(min-device-pixel-ratio: 1.3),(min-resolution: 1.3dppx)
    background-image: image-url($image2x)
    background-size: image-width($image) image-height($image)

// usage for „logo.png” + „logo2x.png”
.logo
  +background-2x('logo')

// usage for „logo.jpg” + „logo2x.jpg”
.logo
  +background-2x('logo', 'jpg')