function sidescroller_beginScrollRight(id) {
    var elem = document.getElementById(id + '_scrollerDiv');
    elem.rightVelocity = 2;
    elem.rightAcceleration = 0.25;
    window.setTimeout("sidescroller_scrollRight('" + id + "');", 25);
}
function sidescroller_stopScrollRight(id) {
    var elem = document.getElementById(id + '_scrollerDiv');
    elem.rightAcceleration = -1.5;
}
function sidescroller_scrollRight(id) {
    var elem = document.getElementById(id + '_scrollerDiv');
    var width =  elem.childNodes[0].offsetWidth;
    var parent = elem.parentNode;
    var parentWidth = parent.offsetWidth;
    
    elem.rightVelocity = Math.min(elem.rightVelocity + elem.rightAcceleration, 12);
    if (elem.rightVelocity > 0) {
        var minLeft = Math.min(parentWidth - width, 0);
        var left = parseInt(elem.style.left) - elem.rightVelocity;
        elem.style.left = (left < minLeft ? minLeft : left) + "px";
        window.setTimeout("sidescroller_scrollRight('" + id + "');", 25);
    }
}
function sidescroller_beginScrollLeft(id) {
    var elem = document.getElementById(id + '_scrollerDiv');
    elem.leftVelocity = 2;
    elem.leftAcceleration = 0.25;
    window.setTimeout("sidescroller_scrollLeft('" + id + "');", 25);
}
function sidescroller_stopScrollLeft(id) {
    var elem = document.getElementById(id + '_scrollerDiv');
    elem.leftAcceleration = -1.5;
}
function sidescroller_scrollLeft(id) {
    var elem = document.getElementById(id + '_scrollerDiv');
    
    elem.leftVelocity = Math.min(elem.leftVelocity + elem.leftAcceleration, 12);
    if (elem.leftVelocity > 0) {
        var left = Math.min(parseInt(elem.style.left) + elem.leftVelocity, 0);
        elem.style.left = left + "px";
        window.setTimeout("sidescroller_scrollLeft('" + id + "');", 25);
    }
}