display stopped by another program

[Alex Ormond <ormond solonel com>]

Hello, Help Please,

I have written an initial version of a simple Cellular Automata program 
using
GTKmm for the UI. Mostly the program works fine, however sometimes the 
program
stops displaying the sequence of Gdk::Pixbuf that it generates. This happens
when I'm interacting with the UI of another program running on the same
machine, usually when I drag something using the cursor.

The program works by creating a std::thread and in it starting a standard
"while" loop.  The code in the loop in the thread changes the data in a 
Pixbuf
on each iteration.  It also checks a mutex, a ConditionVariable, and a 
global
variable so the loop can be interrupted from the UI (details available if
needed). After the Pixbuf data is regenerated the Pixbuf is put again 
into the
Gtk::Image in the UI.

Any idea of how interacting with a separate program UI could affect this 
program?
I'd be more than happy to send you the whole program if that would help.

Many Thanks in Advance,

Alex Ormond