The BLEU project was created with C++, OGRE, RBGUI, and OIS.
Obviously the code structure is not the most ideal imaginable, but I was hard pressed for time when I wrote it.
If I were to write it today, it would be completely different. As you can see in my GPE documentation, I no longer use the friend keyword quite so liberally (In fact, haven't used it once in GPE). The naming convention I have used is a bit wonky as well. In addition the scoping for all the variables, methods, etc...