var nDots = 6;
var Xpos = 0;
var Ypos = 0;
var DELTAT = .01;
var SEGLEN = 10;
var SPRINGK =10;
var MASS = 1;
var GRAVITY = 50;
var RESISTANCE = 10;
var STOPVEL = 0.1;
var STOPACC = 0.1;
var DOTSIZE = 10;
var BOUNCE = 0.75;
var isNetscape = navigator.appName=="Netscape";
var followmouse = true;
init();
function init()
{
        var i = 0;
        dots = new Array();
        for (i = 0; i < nDots; i++) {
                dots[i] = new dot(i);
        }

        if (!isNetscape) {
                setInitPositions()
        }
        for (i = 0; i < nDots; i++) {
                dots[i].obj.left = dots[i].X;
                dots[i].obj.top = dots[i].Y;
        }
        if (isNetscape) {
                startanimate();
        } else {
                setTimeout("startanimate()", 3000);
        }
}
function dot(i) 
{
        this.X = Xpos;
        this.Y = Ypos;
        this.dx = 0;
        this.dy = 0;
        if (isNetscape) {       
                this.obj = eval("document.dot" + i);
        } else {
                this.obj = eval("dot" + i + ".style");
        }
}
function startanimate() {       
        setInterval("animate()", 20);
}
function setInitPositions()
{
        var startloc = document.all.tags("LI");
        var i = 0;
        for (i = 0; i < startloc.length; i++) {
                dots[i+1].X = startloc[i].offsetLeft +
                                        startloc[i].offsetParent.offsetLeft;
                dots[i+1].Y = startloc[i].offsetTop +
                                        startloc[i].offsetParent.offsetTop +
                                        DOTSIZE/2;
        }
        dots[0].X = dots[1].X;
        dots[0].Y = dots[1].Y - SEGLEN;
}
function MoveHandler(e)
{
        Xpos = e.pageX;
        Ypos = e.pageY;   
        return true;
}
function MoveHandlerIE() {
  Xpos = window.event.x;
  Ypos = window.event.y;          
}
if (isNetscape) {
        document.captureEvents(Event.MOUSEMOVE);
        document.onMouseMove = MoveHandler;
} else {
        document.onmousemove = MoveHandlerIE;
}
function vec(X, Y)
{
        this.X = X;
        this.Y = Y;
}
function springForce(i, j, spring)
{
        var dx = (dots[i].X - dots[j].X);
        var dy = (dots[i].Y - dots[j].Y);
        var len = Math.sqrt(dx*dx + dy*dy);
        if (len > SEGLEN) {
                var springF = SPRINGK * (len - SEGLEN);
                spring.X += (dx / len) * springF;
                spring.Y += (dy / len) * springF;
        }
}
function animate() {    
        var start = 0;
        if (followmouse) {
                dots[0].X = Xpos;
                dots[0].Y = Ypos;       
                start = 1;
        }
        for (i = start ; i < nDots; i++ ) {
                var spring = new vec(0, 0);
                if (i > 0) {
                        springForce(i-1, i, spring);
                }
                if (i < (nDots - 1)) {
                        springForce(i+1, i, spring);
                }
                var resist = new vec(-dots[i].dx * RESISTANCE,
                                                         -dots[i].dy * RESISTANCE);
                var accel = new vec((spring.X + resist.X)/ MASS,
                                                        (spring.Y + resist.Y)/ MASS + GRAVITY);
            dots[i].dx += (DELTAT * accel.X);
                dots[i].dy += (DELTAT * accel.Y);
                if (Math.abs(dots[i].dx) < STOPVEL &&
                    Math.abs(dots[i].dy) < STOPVEL &&
                    Math.abs(accel.X) < STOPACC &&
                        Math.abs(accel.Y) < STOPACC) {
                  dots[i].dx = 0;
                  dots[i].dy = 0;
                }
                dots[i].X += dots[i].dx;
                dots[i].Y += dots[i].dy;
                var height, width;
                if (isNetscape) {
                    height = window.innerHeight;
                    width = window.innerWidth;
                } else {        
                    height = document.body.clientHeight;
                    width = document.body.clientWidth;
                }
                if (dots[i].X < 0) {
                        if (dots[i].dx < 0) {
                                dots[i].dx = BOUNCE * -dots[i].dx;
                        }
                        dots[i].X = 0;
                }
                dots[i].obj.left = dots[i].X;                   
                dots[i].obj.top =  dots[i].Y;           
        }
}