How should a program be structured code wise? I have been talking to pouya about this. He uses a base abstract class that contains other classes, which contain the functions that the program uses (as far as I can understand it). I have been using a gamestate based thing where the whole program controlled by the gamestate - like a giant finite state machine. When I need some more code added, I add on another .h and another .cpp file with a new class in them and some functions. I have classes for d3d, input, sprite stuff, etc. Does anyone know of any articles that deal with how to structure a program codewise?

Well, anyone? How is a huge project like a game structured?