The Hero class will inherit from GameObject and will be responsible for handling the state machine of the hero and collision response, among a few other things. The constructor for the Hero class looks something like this:

Hero::Hero()
{
  type_ = E_GAME_OBJECT_HERO;
  state_ = E_HERO_STATE_NONE;
  is_on_ground_ = false;
  current_ground_height_ = 0.0f;
  platform_below_ = NULL;
}

We start off by setting the type_ of this object to E_GAME_OBJECT_HERO. We then initialize the member variables. The state_ variable (like you saw in Chapter 5, Let's Get Physical!) is the key to maintaining the state machine for the hero's behavior. We also have an is_on_ground_ flag that indicates when the hero is standing on a surface, which could be either a brick or a moving platform. So, we can set the appropriate state accordingly. We also have a current_ground_height_ variable that measures the height the hero has managed to reach and is at currently. This increases as the hero moves higher...