var offX = 15; 
var offY = -100;
function mouseX(evt) {
  if (!evt) evt = window.event;
  if (evt.pageX) return evt.pageX;
  else if (evt.clientX)return evt.clientX + (document.documentElement.scrollLeft ?  document.documentElement.scrollLeft : document.body.scrollLeft);
  else return 0;
}
function mouseY(evt) {
  if (!evt) evt = window.event;
  if (evt.pageY) return evt.pageY;
  else if (evt.clientY)return evt.clientY + (document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop);
  else return 0;
}
function follow(evt) {
  if (document.getElementById) {
    var obj = document.getElementById('follower').style;
    obj.left = (parseInt(mouseX(evt))+offX) + 'px';
    obj.top = (parseInt(mouseY(evt))+offY) + 'px';
  }
}

function dlOver(prev){
  if(prev == undefined || prev == "") return;
  obj = document.getElementById('follower')
  obj.style.display = 'block';
  
  img = document.getElementById('follow_img');
  img.src = prev;
  document.onmousemove = follow;
}

function dlOut(){
  obj = document.getElementById('follower')
  obj.style.display = 'none';
  
  img = document.getElementById('follow_img');
  img.src = '/images/clear.gif';
  document.onmousemove = null;
}