var eventImages = new Array()

eventImages[0] = 'images/1.jpg'
eventImages[1] = 'images/2.jpg'
eventImages[2] = 'images/3.jpg'

var j = 0
var p = eventImages.length;
var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = eventImages[i]
}
var whichImage = Math.round(Math.random()*(p-1));
function rotateEvent(){
document.write('<img src="'+eventImages[whichImage]+'">');
}