ecmascript:

function initialize ()
{
	index = 0;
	viewpointCount = viewpoints.length;
	traceEnabled = TraceHolderNode.loop;

	tracePrint ('initialize: viewpoints.length=' + viewpointCount);
	tracePrint ('initialize: Viewpoint [' + index + '] ' + viewpoints[index].description);

	if (TriggerNode.enabled=='false') return;
	if (viewpointCount > 0) viewpoints[index].set_bind = true;
}

function set_enabled (newValue, timeStamp)
{
	enabled = newValue;
	tracePrint ('enabled=' + newValue);
        if ((newValue == true) && (viewpoints.length >= 1))
            viewpoints[0].bind = true;
}

function triggerNext(triggerTime, timeStamp)
{
	if ((TriggerNode.enabled=='false') || (viewpointCount==0)) return;
	if (index < viewpointCount - 1)
		index++;
	else	index = 0;
	if (viewpointCount > 1) viewpoints[index].set_bind = true;
	tracePrint ('triggerNext: Viewpoint [' + index + '] ' + viewpoints[index].description);
}

function previous (value, timeStamp)
{
  if ((TriggerNode.enabled=='false') || (viewpointCount==0)) return;
  if (value==true) // trigger on true events only
  {
	if (index > 0)
		index--;
	else	index = viewpointCount - 1;
	if (viewpointCount > 1) viewpoints[index].set_bind = true;
	tracePrint ('previous: Viewpoint [' + index + '] ' + viewpoints[index].description);
  }
}
function next (value, timeStamp)
{
  if ((TriggerNode.enabled=='false') || (viewpointCount==0)) return;
  if (value==true) // trigger on true events only
  {
	if (index < viewpointCount - 1)
		index++;
	else	index = 0;
	if (viewpointCount > 1) viewpoints[index].set_bind = true;
	tracePrint ('next: Viewpoint [' + index + '] ' + viewpoints[index].description);
  }
}

function tracePrint(outputString)
{
	if (traceEnabled) Browser.println ('[ViewpointSequencer] ' + outputString);
}

function alwaysPrint(outputString)
{
	Browser.println ('[ViewpointSequencer] ' + outputString);
}