void FHierarchicalLODUtilities::DestroyCluster(ALODActor* InActor)
{
// Find if it has a parent ALODActor
AActor* Actor = CastChecked<AActor>(InActor);
UWorld* World = Actor->GetWorld();
ALODActor* ParentLOD = GetParentLODActor(InActor);
const FScopedTransaction Transaction(LOCTEXT("UndoAction_DeleteCluster", "Deleting a (invalid) Cluster"));
Actor->Modify();
World->Modify();
if (ParentLOD != nullptr)
{
ParentLOD->Modify();
ParentLOD->RemoveSubActor(Actor);
}
// Clean out sub actors and update their LODParent
while (InActor->SubActors.Num())
{
AActor* SubActor = InActor->SubActors[0];
SubActor->Modify();
InActor->RemoveSubActor(SubActor);
}
// Also destroy the cluster's data
DestroyClusterData(InActor);
World->DestroyActor(InActor);
if (ParentLOD != nullptr && !ParentLOD->HasValidSubActors())
{
DestroyCluster(ParentLOD);
}
}
void FHierarchicalLODUtilities::DestroyLODActor(ALODActor* InActor)
{
const FScopedTransaction Transaction(LOCTEXT("UndoAction_DeleteLODActor", "Delete LOD Actor"));
UWorld* World = InActor->GetWorld();
World->Modify();
InActor->Modify();
ALODActor* ParentActor = FHierarchicalLODUtilities::GetParentLODActor(InActor);
FHierarchicalLODUtilities::DestroyCluster(InActor);
World->DestroyActor(InActor);
if (ParentActor && !ParentActor->HasValidSubActors())
{
ParentActor->Modify();
FHierarchicalLODUtilities::DestroyLODActor(ParentActor);
}
}
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;
}
const bool FHierarchicalLODUtilities::RemoveActorFromCluster(AActor* InActor)
{
checkf(InActor != nullptr, TEXT("Invalid InActor"));
bool bSucces = false;
ALODActor* ParentActor = FHierarchicalLODUtilities::GetParentLODActor(InActor);
if (ParentActor != nullptr)
{
const FScopedTransaction Transaction(LOCTEXT("UndoAction_RemoveActorFromCluster", "Remove Actor From Cluster"));
ParentActor->Modify();
InActor->Modify();
bSucces = ParentActor->RemoveSubActor(InActor);
if (!ParentActor->HasValidSubActors())
{
DestroyCluster(ParentActor);
}
}
return bSucces;
}