function beginAnim() {
	window.speed = 1;
	window.sceneBg = getElement("SceneBg");
	window.sceneFg = getElement("SceneFg");
	window.sceneX = 0;
	window.slideAnim = window.setInterval(doAnimStep, 1000/10);
}

function getElement(id) {
	var elem = false;
	if (document.getElementById) { elem = document.getElementById(id); }
	else if (document.all) { elem = document.all[id]; }
	else if (document.layers) { elem = document.layers[id]; }
	return elem;
}

function doAnimStep() {
	window.sceneX += window.speed;
	window.sceneFg.style.backgroundPosition = window.sceneX + "px";
	window.sceneBg.style.backgroundPosition = window.sceneX * 0.8 + "px";
}

function onIconClick(pIndex) {
	var img = getElement("icon" + pIndex);
	var isOn = (img.style.opacity == "1");

	for (var i = 1; i < 7; ++i) {
		img = getElement("icon" + i);

		if (isOn) {
			img.style.opacity = img.style.filter = "";
		}
		else {
			var a = (i == pIndex ? 100 : 33);
			img.style.opacity = (a / 100) + "";
			img.style.filter = "alpha(opacity=" + a + ")";
		}
	}

	var screen = getElement("screenImg");
	screen.src = "images/fragmental_screen" + pIndex + ".jpg";
	screen.style.visibility = (isOn ? "hidden" : "visible");
	screen.style.width = (isOn ? "0px" : "452px");
	screen.style.marginTop = (isOn ? "0px" : "9px");
}