Dereferencing Actor Pointers?

[Valencer]

Hello All!

I am wondering how exactly ZScript works with pointers in terms of type casting and pointers.

This is how an actor pointer would be type casted in ZScript

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SomeClassThing classThing;
classThing = SomeClassThing( actorPointer );

If I were to do this...

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classThing.member++;

Am I incrementing the original SomeClassThing's member ( from the given pointer ), or the member from a local copy of SomeClassThing.

If it is a local copy, is there any way to write to the original class instance and its members?

I've seen this syntax around, which I thought indicates that it is a class pointer, but I do not know how to use it ( in terms of 'dereferencing' it and writing to its members ).

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Class< SomeClassThing > classThingPtr;

[phantombeta]

ZScript class pointers don't need to be manually dereferenced.

I've seen this syntax around, which I thought indicates that it is a class pointer, but I do not know how to use it ( in terms of 'dereferencing' it and writing to its members ).

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Class< SomeClassThing > classThingPtr;

That's not related to pointers at all. That stores a class type. You can use it like this:

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class test : Actor {
    states {
    Spawn:
        BAL1 A -1;
        stop;
    }
}
[...]
class<Actor> actorToSpawn = 'test';
Actor.Spawn (actorToSpawn, (0, 0, 0));

This will spawn an actor of type "test" at XYZ coordinates (0, 0, 0).

[Graf Zahl]

Am I incrementing the original SomeClassThing's member ( from the given pointer ), or the member from a local copy of SomeClassThing.

If it is a local copy, is there any way to write to the original class instance and its members?

There is no copy of the object, you merely create a copy of the pointer. They will both point to the same object. ZScript does not allow duplication of objects, unless some class provides an explicit method for that.

[Valencer]

Thanks for responses everyone, its been very helpful!

ZScript class pointers don't need to be manually dereferenced.

There is no copy of the object, you merely create a copy of the pointer. They will both point to the same object. ZScript does not allow duplication of objects, unless some class provides an explicit method for that.

I thought that it may work similar to what it is in C++, but that does not seem to be the case ( Awesome! ).
It then may seem that there is an error somewhere else in my code!

That's not related to pointers at all. That stores a class type. You can use it like this:

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class test : Actor {
    states {
    Spawn:
        BAL1 A -1;
        stop;
    }
}
[...]
class<Actor> actorToSpawn = 'test';
Actor.Spawn (actorToSpawn, (0, 0, 0));

This will spawn an actor of type "test" at XYZ coordinates (0, 0, 0).

This is very useful! I may be able to write all sorts of Zscript functions that take a class as an argument.

Thanks all for your help!

[Graf Zahl]

I thought that it may work similar to what it is in C++, but that does not seem to be the case ( Awesome! ).

It works like a C++ pointer (e.g. AActor *actor) not like a C++ instance (e.g. AActor actor).