On Jul 20, 2010, at 3:33 AM, Joerg Hoehne wrote:

> Is there (an intended) different behavior between gui and non gui  
> simulations?

Nope.  They should be absolutely, 100% identical.  So this is  
definitely interesting.  What makes it more interesting is that I  
cannot immediately think of a single thing in MASON proper which could  
possibly cause it.  We go through a lot of hoops to make sure that the  
model code is separate from the GUI code.

Perhaps: are you using AsynchronousSteppable?  Or WeakSteppable?  What  
does your GUI code do?  Does it modify the model in any way beyond  
simply reading it to display it?  I see you've customized the  
Schedule, and that worries me a bit.  What does ScheduleExtended do  

Here's another possibility: are you scheduling GUI events of any kind  
on the Schedule?  They should not be scheduled on the Schedule but  
rather on the GUIState's "Minischedule".  In fact, let me know what  
field portrayals and displays you're using in general.  This is a  
common enough mistake that we may want break Steppable into two  
interfaces to make it impossible to compile with this error.