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While building Tagit's website, I came across the need to use compass sprites with hover states on normal and retina devices. Not being able to find anything that would suite my needs, I forked a gist from this Gist and added hover & active parameters. Big thanks to thulstrup and rstacruz!

I created a drop in utility mixin to allow compass to automatically create sprites for normal and retina devices, and also providing hover and active states.

• Generate Normal & Retina Sprites
• Optional Hover & Active States
• Optional Sprite Spacing/Padding

I've provided a demo folder with working sample buttons.

Drop _retina-sprites.scss into your preferred location and link @include it into your main CSS file. I prefer to drop it into a utilities folder with other commonly used helpers.

@import "utilities/retina-sprites";

Create two folders in your images folder. For my example I've created "sprites" for 1x sprites and "sprites-retina" for 2x sprites. In my example I've also created a subfolder called buttons to sprite these as a group. Drop your photo's in these folders, they should have the same file name. Also make sure the retina photo's are divisible by 4. If they are not, it can lead to clipping and shifting.

In your SCSS file, declare where your sprites are located. In this example I have my buttons in a separate scss file, and I place the following in the top of this file.

$sprites: sprite-map("sprites/buttons/*.png");            // import 1x sprites
$sprites2x: sprite-map("sprites-retina/buttons/*.png");   // import 2x sprites

If you would like to add padding to your sprites, use the spacing parameter and double the value for the retina version:

$sprites: sprite-map("sprites/buttons/*.png", $spacing: 10px);            // import 1x sprites, 10px padding
$sprites2x: sprite-map("sprites-retina/buttons/*.png", $spacing: 20px);   // import 2x sprites, 20px padding

Almost ready to rock and roll!! Create a class for your sprite, and use an include to generate it.

.myHoverActiveButton {
	@include retina-sprite(signIn, $hover: true, $active: true);    // imports signIn.png, signIn_hover.png, and signIn_active.png
}

.myHoverButton {
   @include retina-sprite(signIn, $hover: true);                    // imports signIn.png and signIn_hover.png
}

.myBoringButton {
   @include retina-sprite(signIn);                                  // imports signIn.png
}