Scripting Concept

"I/O" is an abbreviation of Inputs and Outputs, and it represents the way actors communicate between each other in the map. In classic terms, actors can either send an "output" to another actor, or receive an "input" from another actor. For example, an actor may send an "output" to another actor when it is destroyed, causing the other actor to change color. This "output" is now considered an "input" of the other actor.

The communication between actors is handled by ActorIOActions. Actions are the driving force behind the whole system. Each action represents an event binding, which calls the selected function when the event is triggered. Actions exist in the game world as objects, with their lifetime tied to the actor - more specifically the ActorIOComponent of the actor.

Best Practices

The I/O system is not a replacement for blueprints! To make the most out of the I/O system, you will want to create a bunch of small "script-like" logic actors that are reusable and serve only one specific purpose. Things like adding/removing items from the player's inventory, updating the current objective in the game, spawning an enemy, or starting a cutscene.