> I would like to have an event display for looking at the 
> results of the 
> Fast MC  (including the PID information from a new reconstructed 
> particle class). I have spent a few days looking at the 
> LCDPlugin event 
> display code and I understand basically how that works and have a 
> modified version of it that I play with. However, I cannot figure out 
> how to make it use the LCDEvent data that has been modified 
> by invoking 
> MCFast (through a driver that includes the PID code). It is set up to 
> use only the original data source with getCurrentEvent().

I dont think that is correct. The event display is invoked after the event is read, and after any processing of analysis routines has been performed. For example the current event display is able to display reconstructed tracks and found jets, both of which can be  created on-the-fly by analysis code.

The event that you get from getCurrentEvent should have any modifications done by the fastmc included. It is important to realize that the event header is in fact a hashtable, you can store anything in it that you like. It has convenience methods for accessing things that we know about, for example 
        
        TrackList tl = event.getTrackList() 

is equivalent to 

        TrackList tl = (TrackList) event.get("TrackList");

By using the put and get methods you can store anything you like (such as a list of PID information), and the event display should be able to access anything that you add.

> 
> Rather than using a plugin, I also considered invoking the 
> display from 
> my driver that invokes FastMC and my analysis code. Which is a 
> preferable approach? I haven't managed to get this to work 
> yet (though I 
> haven't spent a lot of time on it). Are there any examples of this?

The plugin seems like the better way to go. Let me know if the comments above do not solve your problem.

Incidentally, although we have done a poor job of publicising it outside of SLAC, we do have the WIRED event display running with LCD code. It is much more fully featured than the event display that comes with the lcd.jar. If you are planning on doing any substantive work with the event display I would recommend using the WIRED event display. Of course that would entail me telling you how to use it....

Tony