function moveHoofdRijToPrevious(el, dX)
{
    var maxScroll = getMaxScrollRight(el, dX);
    {
        new Effect.Move(el, { x: -maxScroll, y: 0, transition: Effect.Transitions.sinoidal });
    }
}  

function moveHoofdRijToNext(el, dX, breedteFoto)
{
    var innerBreedte = parseAttr(breedteFoto.toString());// = parseAttr(document.getElementById('ctl00_cphFoto_panelFotos').style.width);
    var maxScroll = getMaxScrollLeft(el, dX, getBreedte(), innerBreedte);
    {
        new Effect.Move(el, { x: -maxScroll, y: 0, transition: Effect.Transitions.sinoidal });
    }
} 

function moveToPrevious(el, breedte)
{
    var maxScroll = getMaxScrollRight(el, 172);
    {
        new Effect.Move(el, { x: -maxScroll, y: 0, transition: Effect.Transitions.sinoidal });
    }
}  

function moveToNext(el, breedte, maxRechts)
{
    var innerBreedte = parseAttr(document.getElementById('fotoThumbs').style.width);
    var maxScroll = getMaxScrollLeft(el, 172, 494, innerBreedte);
    {
        new Effect.Move(el, { x: -maxScroll, y: 0, transition: Effect.Transitions.sinoidal });
    }
}

function parseAttr(inAttr)
{
    if (inAttr.length == 0)
    {
        return parseInt(0);
    }
    if (inAttr.indexOf('px') != -1)
    {
        return parseInt(inAttr.substr(0, inAttr.length-2));
           
    }
    return parseInt(inAttr);
}

function getRight(inleft, breedte)
{
    /*var breedte = parseAttr(document.getElementById('ctl00_cphFoto_panelFotos').style.width);*/
    return parseInt(inleft) + parseInt(breedte);
}

function getMaxScrollLeft(el, maxWaarde, outerBreedte, innerBreedte)
{
    var links = parseAttr(document.getElementById(el).style.left);
    var rechts = getRight(links, innerBreedte);
    if (rechts > outerBreedte)
    {
        return Math.min(rechts-outerBreedte, maxWaarde);
    }
    else
    {
        return 0;
    }
}

function getMaxScrollRight(el, maxWaarde)
{
    var links = parseAttr(document.getElementById(el).style.left);
    if (links < 0)
    {
        return Math.max(links, -maxWaarde);
    }
    else
    {
        return 0;
    }
}

function getBreedte()
{

		var frameWidth;
		var IE
					//BROWSER AFMETINGEN:
			if( typeof( window.innerWidth ) == 'number' ) {
			//Non-IE
				frameWidth = window.innerWidth;
				IE = false;
			}
			 else if( document.documentElement &&
			(document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
				//IE 6+ in 'standards compliant mode'
			IE = true
			frameWidth = document.documentElement.clientWidth;
				} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
					//IE 4 compatible
					IE = true
					frameWidth = document.body.clientWidth;
				}
				//alert(frameWidth);
		return frameWidth;		
}

function setAchtergrond(el, fotoBreedte)
{

    var schermbreedte = parseInt(getBreedte());
    var links = 0;
    links = Math.floor((schermbreedte - fotoBreedte)/2);
    //links = -1500;
    document.getElementById(el).style.left = links + 'px';
    document.getElementById(el).style.width = fotoBreedte + 'px';
    document.getElementById(el).style.visibility = 'visible';
    //alert(el + ' ' + links + ' breedte ' + fotoBreedte);
}

function setAchtergrondAanbod(el, fotoBreedte)
{

    var schermbreedte = parseInt(getBreedte());
    var links = 0;
    if (schermbreedte > fotoBreedte)
    {
        links = Math.floor((schermbreedte - fotoBreedte)/2);
    }
    else
    {
        links = 0;
    }
    
    document.getElementById(el).style.left = links + 'px';
    document.getElementById(el).style.visibility = 'visible';
    //alert(el + ' ' + links);
}