this method trys to find the requested image file,
currently it just looks for the image file in the class directory
after checking that it hasn't been passed the full path already
if it can't find the image file, it returns null
here's the main that starts it when it is an application
it does some application specific stuff and then just
creates an instance of this class and calls init
this is the method that draws the pane whenever it needs to
after it has been minimized or whatever
it first checks whether it has been resized, in which case it needs
to redraw itself, then .
this method is called by scrollingimage in response to scrollbar
movements, get the scrollbar value, adjust the starts and ends
and do a partial redraw
a boolean which controls whether transistions are drawn to the far left
of the event box - which is exactly correct - or to the center of the
event box - which may be more visually intuitive
this classes contains all of the common data for the ulv program
and the shared static methods, it is also the class that is
responsible for the maintenance of the configuration file that
stores user preferences