Actor spawning issue

[Valentin_Bonneau]

Hello.

To solidify my knowledge after following toontank course, I’ve tried to work on a personal project (industrial robot environment).
Basically, I need to pick up spare parts with my robot, and place them on a mechanical assembly in my scene.
I need to spawn those spare parts which are based on a class called SparePart, but with different static mesh according to the part.
I’ve tried the function used in toon tank course, and made this function :

void ASpawner::SpawnPart(int PartIndex) 
{

    FVector SpawnLocation = GetActorLocation();
    FRotator SpawnRotation = GetActorRotation();

        // if(PartList[PartIndex])
        // {
            if (SparePartClass)
            {
               UE_LOG(LogTemp, Warning, TEXT("Class pointer valid"));
               ASparePart* TempSparePart = GetWorld()->SpawnActor<ASparePart>(SparePartClass, SpawnLocation, SpawnRotation);
            }
            UE_LOG(LogTemp, Warning, TEXT("Spawning working"));
        // }
    }

Eventually, I need to choose the part I spawn from a list, hence the commented PartList array.
My issue is, as soon as I enter the if statement, the window freezes. This is probably due to a null pointer, but I can’t figure out where the issue is, especially since my test is true…

In the .h file, I’ve declared :

   TSubclassOf<ASparePart> SparePartClass;

Any idea ??

Thank you

[DanM]

How long have you waited when it freezed? It could be an assertion failing which can cause a freeze as it will generate a stacktrace to log out.

[Valentin_Bonneau]

@DanM, What does this mean exactly? What do you mean by assertion and stacktrace?

[Valentin_Bonneau]

I’ve waited something like 3-5 min

[DanM]

Assertion:
Assertion (software development) - Wikipedia,
Asserts | Unreal Engine Documentation
Stacktrace: the call stack that lead up to that assertion failing- Stack trace - Wikipedia

[DanM]

Have you looked at the logs? Could you post the contents?

[Valentin_Bonneau]

Thanks @DanM.
Where can I find the logs if the editor crashes?

[DanM]

Build and PIE logs are in Saved > Logs and crashes in Saved > Crashes > (hash) > ProjectName.log

[Valentin_Bonneau]

@DanM, looks like I don’t get the world :

LoginId:375d871b4a576645bfa61babeb19f8d7
EpicAccountId:1bd19a233db44e6d95f28ed6695b4378

Assertion failed: this->GetWorld() == nullptr [File:E:\UE_4.26\MECATHERM\Source\MECATHERM\Spawner.cpp] [Line: 24] No world!

UE4Editor_Core
UE4Editor_Core
UE4Editor_MECATHERM_8812!ASpawner::BeginPlay() [E:\UE_4.26\MECATHERM\Source\MECATHERM\Spawner.cpp:24]
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor
UE4Editor
UE4Editor
UE4Editor
UE4Editor
kernel32
ntdll

How can I solve this?

[DanM]

That is curious… Where do you have this spawner? I’m a little confused how there’s an actor without a world, honestly.

[Valentin_Bonneau]

Same for me @DanM .
I’ve made a blueprint from my class “Spawner”, and placed it in my scene.
Here you’ve got pictures of everything I’ve done. Do you know anyone else who could help?