Hierachical Finite State Machines
In this post I talk about hierarchical state machines and present a simple implementation, based on the state pattern. It is by no means a comprehensive explanation, and I skim...
Category: Development
C++ delegates
In a previous article I wrote about the ubiquitous observer pattern, which is all about objects (called observers or listeners) that need to be notified when other objects in the...
Client-server framework for a multiplayer game (part 1)
Now that I’ve got a working game engine it’s time to add some interesting features to it. One that I’ve always desired to implement is online multiplayer, the ability to...
Type erasure in C++
Polymorphism is the ability to use objects of different types in a generic way, using the same notation. In C++ there are two forms of polymorphism, dynamic and static polymorphism....
Friendship in C++
Encapsulation is a staple of object-oriented programming: by hiding (or “abstracting away”) the implementation details of a class behind a public interface we can create abstract data types. Users of...
Full class template specialization and full member specialization
Templates are a very powerful feature of C++: they let us parameterize a class, function or variable with some generic types or values (called template parameters), so that by specifying...
Strategy Desing Pattern and variadic class templates
The Strategy design pattern is a perfect example of the OOP tenet that says: “favor composition over inheritance”. Inheritance is indeed powerful when it comes to code reuse, or when...
State Design Pattern
Many systems wait continuously for the occurrence of some event, and they react to the event by performing computations or changing their state. Once the event is handled, they go...
Observer Design Pattern
The Observer Pattern According to the GoF book the Observer pattern “defines a one to many dependency between objects so that when one object changes state, all its dependents are...
Command Design Pattern
The Command Pattern The Gang of Four’s book gives the following definition of the command pattern: “The Command pattern encapsulates a request as an object, letting you parameterize clients with...