var top = (screen.height - 500)/2 ;
var screenY = top ;
var left = (screen.width - 780)/2 ;
var screenX = left ;

var features = 'height=500, width=780, location=no, menubar=no, resizable=no, scrollbars=yes, titlebar=no, toolbar=no' ;
features = features + ", top=" + top + ", left=" + left ;

var edwin ;
function openEditor(op, doctype) {
	edwin = window.open('/edit.php?op='+op+'&type='+doctype, 'editor', features) ;
	edwin.focus() ;
}

var docwin ;
function openDoc(id, title) {
	docwin = window.open('/view.php?id='+id, 'popup', features) ;
	docwin.focus() ;
}

var imgwin ;
function showImage(id) {
	imgwin = window.open('/showimage.php?id='+id, 'image', features) ;
	imgwin.focus() ;
}

var chgwin ;
function showChanges() {
	chgwin = window.open('/changes.php', 'changes', features) ;
	chgwin.focus() ;
}