// Boucing Balls Script
var ballCount = 4;
var balls 	  = new Array();

var ballStart = 100;
var ballEnd   = 200;

function CreateBalls()
{
	for(var x=0;x<ballCount;x++)
	{
		balls[x] = document.getElementById('b'+x);
		balls[x].inc = 0;
		balls[x].currentPos = balls[x].offsetTop;
	}

	window.setInterval("MoveBalls();", 20);
}

function MoveBalls()
{
	var speed;
	for(var x=0;x<ballCount;x++)
	{
		speed = Math.round(((balls[x].currentPos - ballStart) /5));

		if(speed == 0)speed = 1;
		if(balls[x].inc < 0) speed *= -1;

		balls[x].inc = speed;
		balls[x].currentPos += balls[x].inc;

		if(balls[x].currentPos >= ballEnd || balls[x].currentPos <= ballStart)
			balls[x].inc *= -1;

		balls[x].style.top = balls[x].currentPos;
	}
}