I’ve commented at length about this book before; really, just don’t bother. It’s not very good at patterns, not comprehensive, not clear on how to use them for games or why you might want to use them at all.

Google search “design pattern book”. Right, now take any of those books.

If you want game related stuff try “game programming gems”.

This book is free... that’s literally all it has going for it. Wikipedia has better stuff that you know... actually compiles, etc.

If you got any value out of Game Programming Patterns, I cannot strongly enough recommend you go and read an actually good book on design patterns; you’ve probably been mislead by its vague hand waving and incoherent discussion of the various topics.