What's the general use of a pointer? When should it be used?

[TheLastMinotaur]

Hi,

I get that pointers can save memory when referring to a variable but I don’t understand why we store the pointer of Owner via GetOwner() and then essentially save Owner.GetActorLocation() to a FVector.

Wouldn’t you just use FVector ActorLocation = GetActorLocation() directly? Or am I missing something and we are saving memory somehow?

As someone who has done a bit of Java in the past, I’m trying to wrap my head around the concept of a pointer and when it should be used.

[DanM]

@TheLastMinotaur

but I don’t understand why we store the pointer of Owner via GetOwner() and then essentially save Owner.GetActorLocation() to a FVector.

You don’t have to store it in an intermediate variable. Some people just find it easier to read. The compiler can optimise trivial situations such as these.

@TheLastMinotaur

Wouldn’t you just use FVector ActorLocation = GetActorLocation() directly?

We’re coding on a component. You would first need to get the actor it is attached to.

FVector ActorLocation = GetOwner()->GetActorLocation();

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@TheLastMinotaur

I’m trying to wrap my head around the concept of a pointer and when it should be used.

C++ uses value semantics whereas Java uses reference semantics.

void SomeFunction(T Value);
// calling it
SomeFunc(SomeObject);

Value is a copy of SomeObject for all T. If you want to refer to something that already exists you need to use pointers/references; for example, the actor that the component is attached to.

[TheLastMinotaur]

Ahhh, this makes more sense thanks.

I forgot that we are coding on the mover component.

So the GetOwner() function returns the reference, not the copy of the Actor the component is on?

[DanM]

@TheLastMinotaur

So the GetOwner() function returns the reference,

Well a pointer, but yes. You can see that in the return type of the function

AActor* GetOwner() const

- UActorComponent::GetOwner | Unreal Engine 5.2 Documentation