How to offset the center of a Google maps (API v3) in pixels?

Found this question when researching and thought I should provide an answer:

function map_recenter(latlng,offsetx,offsety) {
    var point1 = map.getProjection().fromLatLngToPoint(
        (latlng instanceof google.maps.LatLng) ? latlng : map.getCenter()
    );
    var point2 = new google.maps.Point(
        ( (typeof(offsetx) == 'number' ? offsetx : 0) / Math.pow(2, map.getZoom()) ) || 0,
        ( (typeof(offsety) == 'number' ? offsety : 0) / Math.pow(2, map.getZoom()) ) || 0
    );  
    map.setCenter(map.getProjection().fromPointToLatLng(new google.maps.Point(
        point1.x - point2.x,
        point1.y + point2.y
    )));
}

If your Google maps variable isn’t map use the following call function reference:

function map_recenter(map,latlng,offsetx,offsety) { ...