We carry the user's choice of image map and geometry to the display function where the actual application is carried out. This is accomplished with the two variables textureChoice and displayChoice (see the display function). On the other hand, the action of closing the program is performed within the handler. In particular, we throw the "exception" ProgramExit when the user chooses to close the program. ProgramExit is declared as an empty class. The exception "handler" is built into main with the catch statement.