/**
 * Funciones para el manejo de la galeria de fotos.
 * @author Fabrizio Lozada
 * @version 1.0
 */

function previousPhoto() {

  var prevID = curID - 1;
  if ( prevID < 0 )
     prevID = cnt - 1;
  showPhoto( prevID );
}

function showPhoto( newID ) {

  curID = newID;
  var photo = document.getElementById('photo');
  photo.src = 'photos/' + photos[ curID ];
}

function nextPhoto() {

  var nextID = curID - 1;
  if ( nextID < 0 )
     nextID = cnt - 1;
  showPhoto( nextID );
}