scrollIntoViewIfNeeded

gistfile1.js

// centering doesn't work I don't care fuck you sideways
Element.prototype.scrollIntoViewIfNeeded = function (centerIfNeeded) {
    var box = this.getBoundingClientRect(),
        parentNode = this.parentNode,
        parent = parentNode.getBoundingClientRect();

    var above   = box.top    < parent.top,
        below   = box.bottom > parent.bottom,
        toRight = box.right  > parent.right,
        toLeft  = box.left   < parent.left;

    // still in the box, no need to worry.
    if (!(above || below || toRight || toLeft)) {
        return;
    }

    var alignWithBottom = below && !above;
    if (!centerIfNeeded) {
        return this.scrollIntoView(alignWithBottom);
    }

    // centering is...tricky. You need to take a lot of things into
    //consideration. Fortunately, this is more of a hack than anything in
    //the first place, so I cut a lot of slack.
    if (above || below) {
        parentNode.scrollTop = box.top + parent.height / 2;
    }

    if (toLeft || toRight) {
        parentNode.scrollLeft = box.left + parent.width / 2;
    }
};