var timerlen = 2;
var slideAniLen = 250;

var timerID = new Array();
var startTime = new Array();
var obj = new Array();
var endHeight = new Array();
var moving = new Array();
var dir = new Array();

function slidedown(objname){
        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] = "down";
        startslide(objname);
        
        opacity(objname, 0, 100, 300);
}

function slideup(objname){
        if(moving[objname])
                return;

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

        moving[objname] = true;
        dir[objname] = "up";
        startslide(objname);
        opacity(objname, 100, 0, 300);
}

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

        endHeight[objname] = parseInt(obj[objname].style.height);
        startTime[objname] = (new Date()).getTime();

        if(dir[objname] == "down"){
                obj[objname].style.height = "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 =Math.round(elapsed / slideAniLen * endHeight[objname]);
                if(dir[objname] == "up")
                        d = endHeight[objname] - d;

                obj[objname].style.height = d + "px";
        }

        return;
}

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

        if(dir[objname] == "up")
                obj[objname].style.display = "none";

        obj[objname].style.height = endHeight[objname] + "px";

        delete(moving[objname]);
        delete(timerID[objname]);
        delete(startTime[objname]);
        delete(endHeight[objname]);
        delete(obj[objname]);
        delete(dir[objname]);

        return;
}

function toggleSlide(objname){
  if(document.getElementById(objname).style.display == "none"){
    // div is hidden, so let's slide down
    slidedown(objname);
  }else{
    // div is not hidden, so slide up
    slideup(objname);
  }
}
var zi = 1;
var curr_el = null;


	function picchange(el) {		// move a pic to top Z-index, then fade in
		if (curr_el != el) {
			curr_el = el;
			zi++;
			changeOpac(0,el);
			document.getElementById(el).style.zIndex = zi;
			opacity(el, 0, 100, 500);
		}
	}
	
	
	function opacity(id, opacStart, opacEnd, millisec) {
	    //speed for each frame
	    var speed = Math.round(millisec / 100);
	    var timer = 0;
	
	    //determine the direction for the blending, if start and end are the same nothing happens
	    if(opacStart > opacEnd) {
	        for(i = opacStart; i >= opacEnd; i--) {
	            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
	            timer++;
	        }
	    } else if(opacStart < opacEnd) {
	        for(i = opacStart; i <= opacEnd; i++)
	            {
	            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
	            timer++;
	        }
	    }
	}
	
	//change the opacity for different browsers
	function changeOpac(opacity, id) {
	    var object = document.getElementById(id).style;
	    object.opacity = (opacity / 100);
	    object.MozOpacity = (opacity / 100);
	    object.KhtmlOpacity = (opacity / 100);
	    object.filter = "alpha(opacity=" + opacity + ")";
	}
	
	
	function enlarger(fil) {
		var ur = "enlarge.php?loc=" + fil;
		window.open(ur,null,"width=150,height=150");
	}