var BasicAnimations = new function() {
     
    this.setOpacity = function (id, opacity)
	{
		var e = document.getElementById(id);
		e.style.opacity = opacity/100;
	}
	
	// 
	// name: fade
	// @param startOpacity betwin 0 and 100
	// @param stopOpacity betwin 0 and 100
	// @param duration in millisecs
	this.fade = function(id, startOpacity, stopOpacity, duration)
	{
		var e = document.getElementById(id);
		var speed = Math.round(duration/Math.abs(stopOpacity - startOpacity));
		e.style.opacity = startOpacity/100;
		if (startOpacity < stopOpacity)
		{
			for (i = startOpacity; i < stopOpacity; i++)
			{
				setTimeout('BasicAnimations.setOpacity("'+id+'","'+i+'")', speed*i);
			}
		}else{
			for (i = startOpacity; i > stopOpacity; i--)
			{
				setTimeout('BasicAnimations.setOpacity("'+id+'","'+i+'")', speed*(startOpacity-i+1));
			}
		}
	}
	
	this.setSize = function (id, width, height)
	{
		var e = document.getElementById(id);
		
		e.style.width = width+"px";
		//e.style.height = height+'px';
		//alert(e.style.width);
	}
	
	this.unfold = function(id, startWidth, finalWidth, startHeight, finalHeight, step)
	{
		var e = document.getElementById(id);
		BasicAnimations.setSize(id, startWidth, startHeight);
		
		/*for (i = 0; i < finalWidth; i+step)
			{
				for (j = 0; j < finalHeight; i+step)
				{
					setTimeout('BasicAnimations.setSize('+id+', "'+i+'","'+j+'")', speed*i);
				}
			}*/
	}
}