var screenh;
var screenw;
var screenratio;
var imageratio;

var pics = 7;
var dt = new Date();
var hr = dt.getSeconds();
var ra = hr % pics;
var r1 = ++ra;

function getBrowserSize() {
	if (window.innerHeight) {
		screenh = window.innerHeight;
		screenw = window.innerWidth;
	}
	else if (document.documentElement && document.documentElement.clientHeight) {
		screenh = document.documentElement.clientHeight;
		screenw = document.documentElement.clientWidth;
	}
	else if (document.body) {
		screenh = document.body.clientHeight;
		screenw = document.body.clientWidth;
	}
	screenratio = screenh/screenw;
}

function getImageSize() {
	orgimage = document.getElementById('backgroundimage');
	orgwidth = orgimage.width;
	orgheight = orgimage.height;
	imageratio = orgheight/orgwidth;
}

function toggle_visibility(id) {
   var e = document.getElementById(id);
   if(e.style.display == 'block')
	  e.style.display = 'none';
   else
	  e.style.display = 'block';
}

function setDivDimensions(ID,height,width,position) {
	var element = document.getElementById(ID);
	element.setAttribute("width",width);
	element.setAttribute("height",height);
	element.style.display = "block";
}

function resizeDivs() {

	getBrowserSize(screenratio,screenw,screenh);
	getImageSize();

	if (screenratio >= imageratio) {
		newheight = screenh;
		newwidth = screenh/imageratio;
	}
	else {
		newheight = imageratio*screenw;
		newwidth = screenw;
	}
	setDivDimensions("backgroundimage",newheight,newwidth);
}

var randompic = '<img src="/fileadmin/images/drostes/fullscreenbackgrounds/'+r1+'.jpg" id="backgroundimage" />';
var randompicbl = '<img src="/fileadmin/images/boerderijlodges/fullscreenbackgrounds/'+r1+'.jpg" id="backgroundimage" />';