Delaying a Trigger (Tutorial #2)

The second video showed me how to create an event off of a trigger. A trigger is basically a volume, or a 3D shape, that will detect whenever another object in the scene is overlapping it. The events are called from a reference to that volume with the node names of "OnActorBeginOverlap" and "OnActorEndOverlap." Essentially it is the "OnTriggerEnter" and "OnTriggerExit" functions in Unity. We also learned how to create and use the functionality of a "Delay" node. Here is a image of the improved BluePrints.



Another cool funtionality we explored in this video was that multiple events can call the same function. Here you can see both "OnActorBeginOverlap" and "OnActorEndOverlap" are connected to the same function.

Learning to use the "Delay" node was helpful because it helped represent how Unreal Editor 4 (UE4) could call functions.  In UE3, you could call multiple actions (now known as functions) from the same event. The bad part about this was that there was no way to know what order those actions would happen in. It could activate the actions in a different order each time, and there was no way to control it either.

But in UE4, functions are all called in order from left to right. It is kind of like a daisy-chain way to go from one action to another. It is called Sequential Firing. So all Blueprints in UE4 have to go this way.

Here is a video that shows the result of the light being toggled on an overlap enter or exit, along with a delay before the function is called each time.