Can an actor spawn with a random static mesh?

Development Asset Creation
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1

Hi I’m working on this Tetris like puzzle game where a user can select blocks to drop into a scene. It’s been going fairly well so far except I think am having trouble with some basic aspects of how actors work.

My assumption was that I could feed the FObjectFinder a randomly determined resource path on initialization and every time my actor class is spawned I would get a different static mesh… However it seems that is not the case. Using the following code I am able to spawn a random mesh, but it is only random on each launch of the editor and not each time I spawn the class using ARocks12Block* NewRock = GetWorld()->SpawnActor(RockLocation, FRotator(0,0,0));

  // Create dummy root scene component
  DummyRoot = CreateDefaultSubobject<USceneComponent>(TEXT("Dummy0"));
  RootComponent = DummyRoot;

  // Create static mesh component
  BaseMesh = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("BaseMesh0"));

  int32 randomItem = FMath::FRandRange(0, 11);
  static const TCHAR* mesh = *meshes[randomItem];
  static const TCHAR* material = *materials[randomItem];

  ConstructorHelpers::FObjectFinderOptional<UStaticMesh> RockMesh = mesh;
  ConstructorHelpers::FObjectFinderOptional<UMaterial> RockMaterial = material;


  static int32 RockCounter = 0;
  FString RockName = FString::Printf(TEXT("NewMesh_%d"), RockCounter++);
  newMesh = NewObject<UStaticMesh>(this, UStaticMesh::StaticClass(), *RockName);

  static int32 RockMatCounter = 0;
  FString RockMatName = FString::Printf(TEXT("NewMat_%d"), RockMatCounter++);
  newMaterial = NewObject<UMaterial>(this, UMaterial::StaticClass(), *RockMatName);

  newMesh = RockMesh.Get();
  newMaterial = RockMaterial.Get();

  BaseMesh->SetStaticMesh(newMesh);
      
  BaseMesh->SetRelativeScale3D(FVector(1.f,1.f,0.25f));
  BaseMesh->SetRelativeLocation(FVector(0.f,0.f,25.f));

  BaseMesh->SetMaterial(0, newMaterial);

  BaseMesh->SetSimulatePhysics(true);
  BaseMesh->WakeRigidBody();

  BaseMesh->AttachToComponent(DummyRoot, FAttachmentTransformRules::KeepWorldTransform);

My working assumption is that stuff in the class constructor only gets loaded once when the game is launched, but if this is the case how do I achieve my goal of selecting a different mesh for each actor spawn.

My other thought was to create a blueprint class with an exposed static mesh property, add as many as I need to the level while setting static mesh for each, but I wasn’t sure how I would then use these to spawn new instances.

Any suggestions would be MUCH appreciated as I am a little lost!

2

Never mind :slight_smile: I figured out a way to deal with the problem. Just ended making a UPROPERTY TArray in another spawning actor

TArray> theRocks;

Then I filled the array in the editor using blueprints derived from the original Actor class I wanted to spawn with their static mesh set in the editor, like so:

NewRock = GetWorld()->SpawnActor(theRocks[num], RockLocation, FRotator::ZeroRotator, spawnParams);