/* Main Javascript file for Abraxas Photography */

// $ function for gettting element id's (to cut down typing)
function $(id) 
{
	return document.getElementById(id); 
}

// Set a function to control opacity of an element
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 = $(id).style; 
	object.opacity = (opacity / 100);
	object.MozOpacity = (opacity / 100);
	object.KhtmlOpacity = (opacity / 100);
	object.filter = "alpha(opacity=" + opacity + ")";
}

// Function for switching images on mouseover event
function SimpleSwap(el,which) 
{
  el.src=el.getAttribute(which || "origsrc");
}

// Initial image swap page setup called from body.onload
function SimpleSwapSetup() 
{
  var x = document.getElementsByTagName("img");
  for (var i = 0; i < x.length; i++)
  {
    var oversrc = x[i].getAttribute("oversrc");
    if (!oversrc) continue;
      
    // preload image -
    // comment the next two lines to disable image pre-loading
    x[i].oversrc_img = new Image();
    x[i].oversrc_img.src = oversrc;

    // set event handlers
    x[i].onmouseover = new Function("SimpleSwap(this,\'oversrc\');");
    x[i].onmouseout = new Function("SimpleSwap(this);");

    // save original src
    x[i].setAttribute("origsrc", x[i].src);
  }
}

// Function for preloading images for main site while visitor is at intro page
function preloadImg()
{
  var images = new Array();
  images[0] = "body_background.gif";
  images[1] = "background.gif";
  images[2] = "header.gif";
  images[3] = "menu_background.jpg";
  images[4] = "ultimate_visuals_logo.png";
  images[5] = "hd_camera.png";
  images[6] = "tabs/home_tab.png";
  
  for (var i = 0; i < images.length; i++) 
  {
	var source = 'http://www.ultimatevisuals.com/images/' + images[i];
      
    // preload image
    var new_img = new Image();
    new_img.src = source;
  }
}

// Wrapper function for controlling intro page loading
function introSetup()
{
	opacity('intro_bkg', 0, 100, 1000);
	setTimeout('opacity("intro_logo", 0, 100, 1000)', 200);
	setTimeout('opacity("intro_reel", 0, 100, 1000)', 200);
	setTimeout('preloadImg()', 1200);
}