[UE5] Damage Framework

AActor::TakeDamage 함수

float AActor::TakeDamage(float DamageAmount, FDamageEvent const& DamageEvent, AController* EventInstigator, AActor* DamageCauser)
{
	float ActualDamage = DamageAmount;

	UDamageType const* const DamageTypeCDO = DamageEvent.DamageTypeClass ? DamageEvent.DamageTypeClass->GetDefaultObject<UDamageType>() : GetDefault<UDamageType>();
	if (DamageEvent.IsOfType(FPointDamageEvent::ClassID))
	{
		// point damage event, pass off to helper function
		FPointDamageEvent* const PointDamageEvent = (FPointDamageEvent*) &DamageEvent;
		ActualDamage = InternalTakePointDamage(ActualDamage, *PointDamageEvent, EventInstigator, DamageCauser);

		// K2 notification for this actor
		if (ActualDamage != 0.f)
		{
			ReceivePointDamage(ActualDamage, DamageTypeCDO, PointDamageEvent->HitInfo.ImpactPoint, PointDamageEvent->HitInfo.ImpactNormal, PointDamageEvent->HitInfo.Component.Get(), PointDamageEvent->HitInfo.BoneName, PointDamageEvent->ShotDirection, EventInstigator, DamageCauser, PointDamageEvent->HitInfo);
			OnTakePointDamage.Broadcast(this, ActualDamage, EventInstigator, PointDamageEvent->HitInfo.ImpactPoint, PointDamageEvent->HitInfo.Component.Get(), PointDamageEvent->HitInfo.BoneName, PointDamageEvent->ShotDirection, DamageTypeCDO, DamageCauser);

			// Notify the component
			UPrimitiveComponent* const PrimComp = PointDamageEvent->HitInfo.Component.Get();
			if (PrimComp)
			{
				PrimComp->ReceiveComponentDamage(DamageAmount, DamageEvent, EventInstigator, DamageCauser);
			}
		}
	}
	else if (DamageEvent.IsOfType(FRadialDamageEvent::ClassID))
	{
		// radial damage event, pass off to helper function
		FRadialDamageEvent* const RadialDamageEvent = (FRadialDamageEvent*) &DamageEvent;
		ActualDamage = InternalTakeRadialDamage(ActualDamage, *RadialDamageEvent, EventInstigator, DamageCauser);

		// K2 notification for this actor
		if (ActualDamage != 0.f)
		{
			FHitResult const& Hit = (RadialDamageEvent->ComponentHits.Num() > 0) ? RadialDamageEvent->ComponentHits[0] : FHitResult();
			ReceiveRadialDamage(ActualDamage, DamageTypeCDO, RadialDamageEvent->Origin, Hit, EventInstigator, DamageCauser);
			OnTakeRadialDamage.Broadcast(this, ActualDamage, DamageTypeCDO, RadialDamageEvent->Origin, Hit, EventInstigator, DamageCauser);

			// add any desired physics impulses to our components
			for (int HitIdx = 0; HitIdx < RadialDamageEvent->ComponentHits.Num(); ++HitIdx)
			{
				FHitResult const& CompHit = RadialDamageEvent->ComponentHits[HitIdx];
				UPrimitiveComponent* const PrimComp = CompHit.Component.Get();
				if (PrimComp && PrimComp->GetOwner() == this)
				{
					PrimComp->ReceiveComponentDamage(DamageAmount, DamageEvent, EventInstigator, DamageCauser);
				}
			}
		}
	}

	// generic damage notifications sent for any damage
	// note we will broadcast these for negative damage as well
	if (ActualDamage != 0.f)
	{
		ReceiveAnyDamage(ActualDamage, DamageTypeCDO, EventInstigator, DamageCauser);
		OnTakeAnyDamage.Broadcast(this, ActualDamage, DamageTypeCDO, EventInstigator, DamageCauser);
		if (EventInstigator != nullptr)
		{
			EventInstigator->InstigatedAnyDamage(ActualDamage, DamageTypeCDO, this, DamageCauser);
		}
	}

	return ActualDamage;
}

간단히 살펴보자면,

float AActor::TakeDamage(
float DamageAmount, 					// 전달할 데미지 수치
FDamageEvent const& DamageEvent, 		// 데미지 이벤트 종류
AController* EventInstigator, 			// 데미지 전달 명령의 가해자 (controller)
AActor* DamageCauser					// 데미지 전달에 사용된 도구
)

이처럼 4가지의 파라미터를 통해 데미지를 피해자 액터 입장에서 관리한다.

무기야, 여러 가지 방식의 물리 액션을 생각할 수 있지만

가장 primitive 한 형태로 검/창/도끼/둔기 등의 한손/양손 무기를 들어 휘두르는 것을 가정해보자.

이 때 필요한 건

물론 기본적인 캐릭터 액터와 더불어,

무기에 대한 액터,

캐릭터의 Skeletal Mesh에 부착할 손에 관련한 Socket 이 필요하다.