If you are following this book chapter by chapter, that means you have already completed the AI chapter, and you already have an idea about how things should be constructed. But let's be more specific here.
There are different ways, methods, and approaches that we can use in order to build a collectables system. The variation comes from the fact that not all games are made the same way, and engineers do not necessarily work using similar methods. But the two most common methods I've found that we can use are as follows:
We build a base collectables class, and then we build some classes inherited from it, each new subclass serving a different type of collectable item. For example, we could have the main
PickupBaseclass for the general behaviors shared between all pickup items, and then derive several classes from it, such asmoney,health,food, and so on, where each type of collectable will behave differently.
On the other hand, we could have just one collectable...