Time for action – Examining inheritance
- We can see an example of this by taking a look at the class tree in UnCodeX, under Actor | Inventory | Weapon | UDKWeapon. Expanding UTWeapon we can see the different types of weapons provided as examples in the UDK:
We can see that
UTBeamWeapon(like the plasma gun we start with when running the game),UTWeap_RocketLauncher, andUTWeap_ShockRifleBaseare amongst our weaponry. Each of these behaves differently, but all of them have common functionality. - Clicking on
UTWeapon, we can see some of its variables./** Initial ammo count if in weapon locker */ var int LockerAmmoCount; /** Max ammo count */ var int MaxAmmoCount; /** Holds the amount of ammo used for a given shot */ var array<int> ShotCost;
What just happened?
Things like MaxAmmoCount and ShotCost are common to all of the weapons, so instead of having to duplicate the variables to all of the subclasses, they're declared in all of the weapons' parent class, UTWeapon. Indeed, if we look at UTWeapon's subclasses like UTWeap_RocketLauncher, we won't find MaxAmmoCount or any of UTWeapon's other variables declared in any of them.
Speaking of weapons, I think it's time we started having a little fun with our code. AwesomeActor has been good to us so far, but he doesn't really do a lot besides sit there and send out log messages. Let's make a weapon.