Classes

That thing about classes that I still have trouble understanding, in the context of my project I am getting the feeling that I could use the mask generating part as a class. As it stands the mall can be created or recreated and it is a separate process to the graphical display of the map.  So it should be possible to set up the code in a way that creates an instance of the class map when a new map is made and dispose of the instance when the clear map function is called. Question is, can I send arguments to a class or does it need to be self contained? This centres around the customizable size of the maps that I want to include in the app. Pity I can't sit down a much around now. Once everyone is in bed I'll have a bash.