var myimages=new Array();
	
function preloadImgs(){
	for (i=0;i<preloadImgs.arguments.length;i++){
		myimages[i]=new Image();
		myimages[i].src="images/" + preloadImgs.arguments[i];
	}
}

//preload left main nav
//preloadImgs("nav_profiles_on.gif", "nav_engineering_on.gif", "nav_artifacts_on.gif", "nav_videostories_on.gif", "nav_imagining_on.gif", "nav_dialogue_on.gif", "nav_about_on.gif");


function swapImg(img1,img2) {
	if (document.images) {
		document[img1].src = img2;
	}
}

function swapImg_main(imgnum,state,defaultnum) {
	if (document.images) {
		if (state=="on") {
			if (defaultnum!=0) {
				document["main"+defaultnum].src = "images/main_nav_"+defaultnum+"_off.gif";
			}
			document["main"+imgnum].src = "images/main_nav_"+imgnum+"_on.gif";
			document["main_ro"].src = "images/main_ro_"+imgnum+".gif";
		} else if (state=="off") {
			document["main"+imgnum].src = "images/main_nav_"+imgnum+"_off.gif";
			if (defaultnum!=0) {
				document["main"+defaultnum].src = "images/main_nav_"+defaultnum+"_on.gif";
			}
			document["main_ro"].src = "images/main_ro_"+defaultnum+".gif";
		}
	}
}