How to cast an inputted superclass to a defined subclass

Development Programming & Scripting
1

I’m pretty new at working in Unreal (and c++ has never been my strongpoint) and I was wondering how to go about taking an inputted object from an engine function, and determining if that object’s class is a specific subclass that I have defined.

Take for example the onHit member function from the example first-person shooter project.

void AExampleProjectile::OnHit(AActor* OtherActor, UPrimitiveComponent* OtherComp, FVector NormalImpulse, const FHitResult& Hit)
{
// Only add impulse and destroy projectile if we hit a physics
if ((OtherActor != NULL) && (OtherActor != this) && (OtherComp != NULL) && OtherComp->IsSimulatingPhysics())
{
	OtherComp->AddImpulseAtLocation(GetVelocity() * 100.0f, GetActorLocation());

    //Check if OtherActor is an instance of my subclass ASpecialWallMesh
    //If so, call subclass' member function ::doStuff
		
	Destroy();
}
}

This seems like a pretty essential piece of knowledge for starting out on extending any unreal classes, so I’m surprised I couldn’t find any useful information about it. I experimented with using dynamic_cast but the documentation on how to use it wasn’t very helpful for the Unreal context and I kept running into ‘invalid target type for dynamic_cast’, so I’m pretty sure I don’t know what I’m doing with it.

2

Use UE’s Cast function instead. If cast is unsuccessful it will return nullptr

ie:

MyActorClass* myActor = Cast<MyActorClass>(OtherActor);
if (IsValid(myActor))
{
...
}
3

Thanks! That worked much more nicely. I’d mark this as an answer if you had submitted it as such.

4

Use UE’s Cast function instead. If cast is unsuccessful it will return nullptr

ie:

MyActorClass* myActor = Cast<MyActorClass>(OtherActor);
if (IsValid(myActor))
{
...
}