var timerlen = 5;
var slideAniLen = 400;

var timerID = new Array();
var startTime = new Array();
var obj = new Array();
var startLeft = new Array();
var endLeft = new Array();
var startRight = new Array();
var endRight = new Array();
var moving = new Array();
var dir = new Array();

function doSlide(objname,slidedir){
        if(moving[objname])
                return;

        if(document.getElementById(objname).style.display != "none")
                return; // cannot slide down something that is already visible

        moving[objname] = true;
        dir[objname] = slidedir;
        startslide(objname);
}

function startslide(objname){
        obj[objname] = document.getElementById(objname);

        if(dir[objname] == "right"){
                startLeft[objname] = -parseInt(obj[objname].style.width);
                endLeft[objname] = 0;
        }
        if(dir[objname] == "left"){
                startRight[objname] = parseInt(obj[objname].style.right);
                endRight[objname] = startRight[objname] + parseInt(obj[objname].style.width);
        }
        startTime[objname] = (new Date()).getTime();

        if(dir[objname] == "down"){
                obj[objname].style.width = "1px";
        }

        obj[objname].style.display = "block";

        timerID[objname] = setInterval('slidetick(\'' + objname + '\');',timerlen);
}

function slidetick(objname){
        var elapsed = (new Date()).getTime() - startTime[objname];

        if (elapsed > slideAniLen) {
                endSlide(objname);
        } else {
                var d;
                if(dir[objname] == "right"){
                        d = Math.round((elapsed / slideAniLen) * (startLeft[objname] - endLeft[objname]));
                        obj[objname].style.left = startLeft[objname] - d + "px";
                }
                if(dir[objname] == "left"){
                        d = Math.round((elapsed / slideAniLen) * (startRight[objname] - endRight[objname]));
                        obj[objname].style.right = startRight[objname] - d + "px";
                }

        }

        return;
}

function endSlide(objname){
        clearInterval(timerID[objname]);

        if(dir[objname] == "right")
                obj[objname].style.left = endLeft[objname] + "px";
        if(dir[objname] == "left")
                obj[objname].style.right = endRight[objname] + 11 + "px";

        delete(moving[objname]);
        delete(timerID[objname]);
        delete(startTime[objname]);
        delete(startLeft[objname]);
        delete(endLeft[objname]);
        delete(startRight[objname]);
        delete(endRight[objname]);
        delete(obj[objname]);
        delete(dir[objname]);

        return;
}