How to use GetConstrainedComponents()?

Development Programming & Scripting C++
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void UPhysicsConstraintComponent::GetConstrainedComponents(UPrimitiveComponent *&OutComponent1, FName &OutBoneName1, UPrimitiveComponent *&OutComponent2, FName &OutBoneName2)

Can someone help me learn how to call this function? The documentation leaves a bit to be desired and I’m not finding much thru googling. I’m relatively new to C++ but I know it’s asking for me to pass in variables so the function can modify them to give me the results but I don’t know how to create the variables to pass in.

I don’t need the bones if that helps. I’m just trying to get the two components connected to this PhysicsConstraint.

Thank You!

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A function can have only one return type (void in this case), but sometimes you need to receive several values from a function. That’s where so-called out parameters come in handy.

Such out parameters are marked with & and DO NOT have const before the parameter type, and more often than not the name starts with Out, although it’s not required.

Using out parameters is easy; you just have to declare the variables before calling the function and pass them as parameters.

UPrimitiveComponent* Component1;
UPrimitiveComponent* Component2;
FName BoneName1;
FName BoneName2;
MyPhysicsConstraintComponent->GetConstrainedComponents(Component1, BoneName1, Component2, BoneName2);

And the values of your variables will be set by the function. Then you can use them as you want.

(If a parameter is marked with const and &, it just means that it will be passed by reference, not by copy. It’s not related to the issue, just for the info.)

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Thanks Tuerer. Unfortunately, I’m still getting errors.

error C4840: non-portable use of class 'FString' as an argument to a variadic function
note: 'FString::FString' is non-trivial
note: see declaration of 'FString::FString'
note: the constructor and destructor will not be called; a bitwise copy of the class will be passed as the argument
note: see declaration of 'FString'```
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Why do you need strings?

Can you show the code, not just an error?

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Sorry that last error was from a ULog on the next line.