window.onerror = null;
var topMargin = 20;
var topOffset = 100;
var slideTime = 100;
var ns4 = (document.layers);
var ns6 = (!document.all && document.getElementById);
var ie4 = (document.all);

function layerObject(id,left)
{
    if (ns6)
    {
    	this.obj = document.getElementById(id).style;
    	this.obj.left = left;
    	return this.obj;
    } else if(ie4 && document.all[id])
    {
        this.obj = document.all[id].style;
        this.obj.left = left;
        return this.obj;
    } else if(ns4)
    {
        this.obj = document.layers[id];
        this.obj.left = left;
        return this.obj;
   }
}

function layerSetup()
{
    floatLyr = new layerObject('floatLayer', 10);
    window.setInterval("main()", 10)
}

function floatObject()
{
    if (ns4 || ns6)
    {
        findHt = window.innerHeight;
    } else if(ie4)
    {
        findHt = document.body.clientHeight;
    }
}

function main()
{
    if (ns4)
    {
        this.currentY = document.layers["floatLayer"].top;
        this.scrollTop = window.pageYOffset;
        mainTrigger();
    } else if(ns6)
    {
        this.currentY = parseInt(document.getElementById('floatLayer').style.top);
        this.scrollTop = scrollY;
        mainTrigger();
    } else if(ie4 && document.all("floatLayer") != null)
    {
        this.currentY = document.all("floatLayer").style.pixelTop;
        this.scrollTop = document.body.scrollTop;
        mainTrigger();
    }
}

function mainTrigger()
{
    var newTargetY = this.scrollTop + this.topMargin + this.topOffset;

    if (this.scrollTop > 35)
    {
        newTargetY = this.scrollTop + this.topMargin;
    }

    if ( this.currentY != newTargetY )
    {
        if ( newTargetY != this.targetY )
        {
            this.targetY = newTargetY;
            floatStart();
        }
        animator();
   }
}

function floatStart()
{
    var now = new Date();

    this.A = this.targetY - this.currentY;
    this.B = Math.PI / ( 2 * this.slideTime );
    this.C = now.getTime();

    if (Math.abs(this.A) > this.findHt)
    {
        this.D = this.A > 0 ? this.targetY - this.findHt : this.targetY + this.findHt;
        this.A = this.A > 0 ? this.findHt : -this.findHt;
    } else
    {
        this.D = this.currentY;
    }
}

function animator()
{
    var now = new Date();
    var newY = this.A * Math.sin( this.B * ( now.getTime() - this.C ) ) + this.D;

    newY = Math.round(newY);
    if (( this.A > 0 && newY > this.currentY ) || ( this.A < 0 && newY < this.currentY ))
    {
        if ( ie4 )
            document.all.floatLayer.style.pixelTop = newY;
        if ( ns4 )
            document.layers["floatLayer"].top = newY;
        if ( ns6 )
            document.getElementById('floatLayer').style.top = newY + "px";
    }
}

function start()
{
    if(ns6||ns4)
    {
        pageWidth = innerWidth;
        pageHeight = innerHeight;
        layerSetup();
        floatObject();
    } else if(ie4)
    {
        pageWidth = document.body.clientWidth;
        pageHeight = document.body.clientHeight;
        layerSetup();
        floatObject();
    }
}