Getting sprite height/width on 2.0 release version

[mishterk]

I'm having some trouble getting the actual heights and widths of images within the sprite. I'm using the 2.0 branch, as I need the multi sprite support, but the following code throws an error for me;

image-height(sprite-file($sprite, $file));

In version 1, I would just use the $sprite variable as the reference to the sprite itself, but I can't quite figure out how to reference a sprite in 2.0. I've tried using the name that I added the sprite with in

retina-sprite-add(name, ... )

... but I still get an error telling me the first argument in sprite-file must be a sprite map.

How do I get the sprite map when using multiple sprites?

Cheers

[mishterk]

For those who might read this looking for an answer; my solution was to pinch some of the code within the extension and create the following;

//  GET THE SPRITE MAP
//  Returns the sprite map so we can reference it to get other properties. Necessary due to multiple sprites
//  not having their own variable.
//  The code is pinched from the @mixin retina-sprite() in RSFCv2.0
@function get-retina-sprite-map($sprite-name) {
    $index : 2;
    $len : length($retina-sprite-names);
    @for $i from $index through $len {
        @if $sprite-name == nth($retina-sprite-names, $i) {
            $index : $i;
        }
    }
    $sprite-map : nth($retina-sprite-sprites, $index);
    @return $sprite-map;
}

The function gets the reference to the correct sprite, so we can then use it as follows;

$sprite-map : get-retina-sprite-map('sprites-registered-name');
height: image-height(sprite-file($sprite-map, $sprite));

If anyone has a better solution, or if I'm completely missing the simple answer that already exists within the extension, I'm all ears.

Cheers!