The structure of the file I/O and factory classes

Have a look at the following diagram, which gives an overview of the classes we will code in this chapter and how the vector of GameObject instances will be shared with the ScreenManager class that we coded in Chapter 19, Game Programming Design Patterns – Starting the Space Invaders ++ Game:

The preceding diagram shows that there is a vector of GameObject instances that's shared between four classes. This is achieved by passing the vector between the functions of the classes by reference. Each class can then carry out its role with the vector and its contents. The ScreenManager class will trigger the LevelManager class when a new level needs to be loaded into the vector. The individual Screen classes and their InputHandler-derived classes, as we saw in Chapter 19, Game Programming Design Patterns – Starting the Space Invaders ++ Game, have access to ScreenManager via ScreenManagerRemoteControl...