// pic presenter

function presPicture(file) {
	document.getElementById('presimage').src = 'images/reference/'+file;
 	document.getElementById('preslayer').style.top = 20+f_scrollTop()+'px';
	document.getElementById('preslayer').style.display = 'block';
	window.setTimeout("presReleaser()",500);
}

function presReleaser() {
	if(document.getElementById('presimage').complete) {
		document.getElementById('presimage').style.display = 'block';
	}
	else {
		window.setTimeout("presReleaser()", 100);
	}
}

function closePres() {
	document.getElementById('presimage').src = "";
	document.getElementById('presimage').style.display = 'none';
	document.getElementById('preslayer').style.display = 'none';
}

function f_scrollTop() {
	return f_filterResults (
		window.pageYOffset ? window.pageYOffset : 0,
		document.documentElement ? document.documentElement.scrollTop : 0,
		document.body ? document.body.scrollTop : 0
	);
}

function f_filterResults(n_win, n_docel, n_body) {
	var n_result = n_win ? n_win : 0;
	if (n_docel && (!n_result || (n_result > n_docel)))
		n_result = n_docel;
	return n_body && (!n_result || (n_result > n_body)) ? n_body : n_result;
}