Time for action – Making a custom weapon

The best way to learn about inheritance is to see it in action, and the most basic way to see it is through a game's weapons. They're easy to modify and are a good starting point for learning about the UDK's classes.

1. Create a new .uc file in our AwesomeGame/Classes folder and call it AwesomeGun.uc . Write the following code in it:

   class AwesomeGun extends UTWeap_RocketLauncher_Content;
   
   defaultproperties
   {
       FireInterval(0)=0.1
       ShotCost(0)=0
   }

2. Compile our class. Now here's where we would ask, "How did it compile? I didn't declare any variables, but we're putting some in our default properties!" This is how inheritance works. We already saw the ShotCost variable in UTWeapon on line 27:

   /** Holds the amount of ammo used for a given shot */
   var array<int> ShotCost;

   If we look higher up in the class tree at Weapon, we can see FireInterval on line 44 (as of the October 2011 build):

   /** Holds the amount of time a single shot takes */
   var()       ...