var isSliding = false;
var sliderWidth = 840;
var left = 0;
var minLeft = 0;

window.onload = function () {
    //Om de limiet te bepalen is de totale breedte nodig..
    totalWidth = parseInt(document.getElementById("totalSliderWidth").innerHTML);
    minLeft = -1 * (totalWidth - sliderWidth);   //Limiet hoe ver de slider naar links mag schuiven
};

function startSliding(direction) {
    isSliding = true;
    slide(direction);
}

function slide(direction) {
    var slider = document.getElementById("slidebox");
    if (!isSliding) return; //Stop sliden

    left += direction;  //1 pixel naar rechts of links

    if (left <= minLeft) {  //Slider mag niet verder naar rechts
        left = minLeft;
        document.getElementById("slider_rightarrow").style.visibility = "visible";
    } else { document.getElementById("slider_rightarrow").style.visibility = "visible"; }

    if (left >= 0) {    //Slider mag niet verder naar links
        left = 0;
        document.getElementById("slider_leftarrow").style.visibility = "visible";
    } else { document.getElementById("slider_leftarrow").style.visibility = "visible"; }

    slider.style.left = left + "px";
    setTimeout("slide(" + direction + ")", 10);   //Over 15ms nog een keer (Snelheid is dus 1px / 15ms)
}

function stopSliding() {
    isSliding = false;
}