document.writeln('<DIV id=dot0 style="VISIBILITY: hidden; WIDTH: 11px; POSITION: absolute; HEIGHT: 11px"><IMG src=""></DIV><DIV id=dot1 style="WIDTH: 11px; HEIGHT: 11px;POSITION: absolute"><IMG src="/Quickstart/ImageLib/yellpaw.gif"></DIV>' + '<BR>');

var nDots = 2;
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 = 11;
var BOUNCE = 0.75;

var isNetscape = navigator.appName=="Netscape";
var followmouse = true;
var dots = new Array();

init();

function init()
{
        var i = 0;
        for (i = 0; i < nDots; i++)
        {
                dots[i] = new dot(i);
        }

        if (!isNetscape)
        {
             //
        }

        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()", 0000);
        }

}

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(dots)
{
        var startloc = document.all.tags("LI");
        var i = 0;

        for (i = 0; i < startloc.length && i < (nDots - 1); i++)
        {
                dots[i+1].X = startloc[i].offsetLeft
                startloc[i].offsetParent.offsetLeft - DOTSIZE;
                dots[i+1].Y = startloc[i].offsetTop +
                startloc[i].offsetParent.offsetTop + 2*DOTSIZE;
        }

        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 + document.body.scrollLeft;
        Ypos = window.event.y + document.body.scrollTop;
}

if (isNetscape)
{
        document.captureEvents(Event.MOUSEMOVE);
        document.onMouseMove = MoveHandler;
}
else
{
        document.onmousemove = MoveHandlerIE;
}

function vec(X, Y)
{
        this.X = X;
        this.Y = Y;
}

// adds force in X and Y to spring for dot[i] on dot[j]

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 + document.scrollTop;
                       width = window.innerWidth + document.scrollLeft;
               }
               else
               {
                       height = document.body.clientHeight + document.body.scrollTop;
                       width = document.body.clientWidth + document.body.scrollLeft;
               }

               if (dots[i].Y >=  height - DOTSIZE - 1)
               {
                       if (dots[i].dy > 0)
                       {
                               dots[i].dy = BOUNCE * -dots[i].dy;
                       }
                       dots[i].Y = height - DOTSIZE - 1;
               }

               if (dots[i].X >= width - DOTSIZE)
               {
                       if (dots[i].dx > 0)
                       {
                               dots[i].dx = BOUNCE * -dots[i].dx;
                       }
                       dots[i].X = width - DOTSIZE - 1;
               }

               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;
       }
}