var picture_max=0;
var picture_index=0;
var picture_alt = ": CLICK to cycle through photos";
	
function change_picture(image, label) {
   var imageDOM;
   var labelDOM;

   // feature disabled in NN 4.x
   if ( (navigator.appName == "Netscape") &&
        (parseInt(navigator.appVersion) == 4) ) {
      return;
   }
   else {
      imageDOM = document.getElementById(image);
      labelDOM = document.getElementById(label);
   }
   ++picture_index;

   if (picture_index > picture_max ) {
      picture_index = 0;
   }
   
   var new_source = imageDOM.src;
   new_source = new_source.replace(/\/\w+.jpg$/,"/"+panel_picture[picture_index]);
   labelDOM.value=picture_label[picture_index];
   imageDOM.src = new_source;
   imageDOM.alt = picture_label[picture_index]+picture_alt;
   
}

function write_random_photo() {
   picture_max= panel_picture.length - 1; //max num - 1 = last index
   var random_index = Math.round( Math.random()*picture_max ); 
   picture_index = random_index;

   if ( (navigator.appName == "Netscape") &&
        (parseInt(navigator.appVersion) == 4) ) {
      picture_alt = "";	
   }
   //document.write("<pre>");   
   document.write("<a onClick=\"change_picture('campus_picture', 'picture_label')\" >");
   document.write("<img  id=\"campus_picture\" name=\"decorativ_photo\" src=\"");
   document.write(picture_url);
   document.write(panel_picture[random_index]);
   document.write("\" alt=\"Decorative photo: ");
   document.write(picture_label[random_index]+picture_alt);
   document.write("\" /></a><br />");
   document.write("<form action=\"none\" title=\"Dynamic Label Box (not used to submit data)\">");
   document.write("<input type=\"text\" size=\"40\" readOnly=\"true\" id=\"picture_label\"");
   document.write("name=\"picture_label\" edit=\"false\" value=\"");
   document.write(picture_label[random_index]);
   document.write("\" /></form><br />");
   //document.write("</pre>");

}

function refresh_picture_label(label) {
   if ( (navigator.appName == "Netscape") &&
        (parseInt(navigator.appVersion) == 4) ) {
      picture_alt = "";
      return;	
   }
   else {
      document.getElementById(label).value=picture_label[picture_index];
   }

}