Class modifiers change the way a class behaves in the editor and in the engine. Two of them we have seen before, but let's go through them to see how they're used.
Class modifiers are always specified at the top of our class in the class declaration line.
This one we've used before, it tells the editor that this class can be placed in the editor. This is useful for most objects such as lights, player starts, weapon spawners, and so on. Some things don't need to be placed in the editor such as our PlayerController
or Pawn, since those are spawned by the game during play. Some things wouldn't make sense to be placeable, such as a HUD. Things like that aren't level-specific, they're spawned and assigned to the player during the game. Generally, placeable classes are only those things that are level-specific and need to be put in a specific place in the level.
We can see an example right in our own code with our AwesomeWeaponUpgrade class:
class AwesomeWeaponUpgrade extends...