//style.top bei NS6 leer!!!
window.onerror = null;
var topMargin = 20;
var slideTime = 1200;
var ie4 = (document.all);
var ns4 = (document.layers);
var ns6 = (!(document.all) && (document.getElementById));
var ID = "floatLayer";

function layerObject(id /*,left*/) 
{
    if (ns6) 
    {
        //this.obj = document.getElementById(id).style;
        //this.obj.left = left;
        //var x = document.getElementById(id).style.top;
        return this.obj;
    }
    else if(ie4) 
    {
        //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"/*, pageWidth * .84*/);
    floatLyr = new layerObject(ID);
    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[ID].top;
        this.scrollTop = window.pageYOffset;
        mainTrigger();
    }
    else if(ns6) 
    {
        this.currentY = parseInt(document.getElementById(ID).style.top);
        this.scrollTop = window.scrollY;
        mainTrigger();
    } 
    else if(ie4) 
    {
        this.currentY = floatLayer.style.pixelTop;
        this.scrollTop = document.body.scrollTop;
        mainTrigger();
    }
}
function mainTrigger() 
{
    var 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[ID].top = newY;
        if ( ns6 )document.getElementById(ID).style.top = newY + "px";
    }
}

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