// toggle gallery image
// @param string img url
// @param int img id
// @param int toggler id
// @param int toggler length
function toggleGalleryImage(url, img_id, toggle_id, toggle_length) {
  // switch all toggler off
  //for (i = 1; i < (toggle_length + 1); ++i) {
  //  document.getElementById("p_"+img_id+"_"+i).src = "images/products/icon_gallery.gif";
  //}
  // switch current toggler on
  //document.getElementById("p_"+img_id+"_"+toggle_id).src = "images/products/icon_gallery_a.gif";
  // change product img
  document.getElementById("p_"+img_id).src = url;
}