gistfile1.txt

function position() {

    var wrapper = $( '.wrapper' );
    var image = $( '.image' );

    var imageHeight = image.height();
    var imageWidth = image.width();
    var imageRatio = imageHeight / imageWidth;
    var linkHeight = link.height();
    var linkWidth = link.width();
    var linkRatio = linkHeight / linkWidth;

    console.log( 'imageHeight:' +  imageHeight ); 
    console.log( 'imageWidth:' +  imageWidth ); 
    console.log( 'linkHeight:' +  linkHeight ); 
    console.log( 'linkWidth:' +  linkWidth ); 

    if( imageRatio > linkRatio ) {
        console.log( 'fitWidth' );

        var diffRatio = imageWidth / linkWidth;
        console.log( 'diffRatio:' +  diffRatio );
        console.log( 'marginTop: -' + ( ( imageHeight / diffRatio - linkHeight ) / 2 ) ) ;


        image
            .css( {
                'width': linkWidth + 'px',
                'height': 'auto',
                'marginTop': '-' + ( ( imageHeight / diffRatio - linkHeight ) / 2 ) + 'px',
                'marginLeft': ' '
            } );

    } else {
        console.log( 'fitHeight' );

        var diffRatio = imageHeight / linkHeight;

        image
            .css( {
                'height': linkHeight + 'px',
                'width': 'auto',
                'marginTop': ' ',
                'marginLeft': '-' + ( ( imageWidth / diffRatio - linkWidth ) / 2 ) + 'px'
            } );
    }

    wrapper
        .addClass( 'positioned' );

    setTimeout( function() {
        image
            .css( {
              'opacity': 0.999
            } )
            .css( {
              'opacity': ' '
            } );
            
        picturefill( {
            elements: [ image[0] ],
            reevaluate: true
        } );

    }, 100 );

}