ALODActor* FHierarchicalLODUtilities::CreateNewClusterFromActors(UWorld* InWorld, AWorldSettings* WorldSettings, const TArray<AActor*>& InActors, const int32 InLODLevel /*= 0*/)
{
checkf(InWorld != nullptr, TEXT("Invalid world"));
checkf(InActors.Num() > 0, TEXT("Zero number of sub actors"));
checkf(WorldSettings != nullptr, TEXT("Invalid world settings"));
checkf(WorldSettings->bEnableHierarchicalLODSystem, TEXT("Hierarchical LOD system is disabled"));
const FScopedTransaction Transaction(LOCTEXT("UndoAction_CreateNewCluster", "Create new Cluster"));
InWorld->Modify();
// Create the cluster
ALODActor* NewCluster = FHierarchicalLODUtilities::CreateNewClusterActor(InWorld, InLODLevel, WorldSettings);
checkf(NewCluster != nullptr, TEXT("Failed to create a new cluster"));
// Add InActors to new cluster
for (AActor* Actor : InActors)
{
checkf(Actor != nullptr, TEXT("Invalid actor in InActors"));
// Check if Actor is currently part of a different cluster
ALODActor* ParentActor = FHierarchicalLODUtilities::GetParentLODActor(Actor);
if (ParentActor != nullptr)
{
// If so remove it first
ParentActor->Modify();
ParentActor->RemoveSubActor(Actor);
// If the parent cluster is now empty (invalid) destroy it
if (!ParentActor->HasValidSubActors())
{
FHierarchicalLODUtilities::DestroyCluster(ParentActor);
}
}
// Add actor to new cluster
NewCluster->AddSubActor(Actor);
}
// Update sub actor LOD parents to populate
NewCluster->UpdateSubActorLODParents();
return NewCluster;
}
