C++ Geometry Collection Caused Crashes

Development Programming & Scripting
, ,
1

Hi there,
I have a problem by scale a Actor with an Geometry Collection in it. All times a Second Actor with an Static Mesh as Component overlap with these Actor, the Unreal Crashes with this Code:

Assertion failed: StaticType() == Obj.GetType() [File:D:\build++UE5\Sync\Engine\Source\Runtime\Experimental\Chaos\Public\Chaos\ImplicitObjectScaled.h] [Line: 523]

I´m init the GC in the constructor like this:

ACTreeFoliageBase::ACTreeFoliageBase()
{
	Middle_GeometryCollection = CreateDefaultSubobject<UGeometryCollectionComponent>("Middle_GeometryCollection");
	Middle_GeometryCollection->SetupAttachment(DefaultSceneRoot);	
	Middle_GeometryCollection->SetNotifyBreaks(true);
	Middle_GeometryCollection->OnChaosBreakEvent.AddDynamic(this, &ACTreeFoliageBase::BreakEvent);
	Middle_GeometryCollection->ObjectType = EObjectStateTypeEnum::Chaos_Object_Static;
	Middle_GeometryCollection->DamageThreshold[0] = 250.f;
	Middle_GeometryCollection->DamageThreshold[1] = 50.f;
	Middle_GeometryCollection->DamageThreshold[2] = 25.f;
	Middle_GeometryCollection->DamagePropagationData.bEnabled = false;
	Middle_GeometryCollection->CollisionGroup = 1;
	Middle_GeometryCollection->CollisionSampleFraction = 0.2f;
	Middle_GeometryCollection->SetEnableDamageFromCollision(false);
	Middle_GeometryCollection->SetCollisionProfileName("Destructible"); 
}

On BeginPlay I load an Geometry Collection and set it as an Rest Collection:

void ACTreeFoliageBase::BeginPlay()
{
Super::BeginPlay();
	
	if (BaseChaosMesh.IsValid() && Middle_GeometryCollection != nullptr)
	{
		Middle_GeometryCollection->SetComponentTickEnabled(false);
		Middle_GeometryCollection->SetRestCollection(BaseChaosMesh.LoadSynchronous());
		Middle_GeometryCollection->SetComponentTickEnabled(true);
	}
}

The strange thing is, I have a similar BP and there it works fine. So what did I missing? If I try to set the Geometry Collection in the Constructor it also didn´t work, so I don´t think it is an Problem with the runtime switching of the GC.

Anyone any idea how I can fix this problem? If you need some code stuff, I can send it later on in this thread, atm I´m on work now.

2

I found out it has to do with the Sphere Trace and / or with the SphereComponent. I delete the Sphere Component and made the Sphere Trace to an Linetrace and now it isn´t Crashing.

3

I fixed it for my purposes by setting the destructible mesh to a collision, ignoring the pawns and thus not reacting to overlap of the capsule component within a pawn. I also changed the Capsule Trace in the Actor tool to a simpler Linetrace. Now I have no more crashes.

But for me this seems to be a general problem within the Unreal Engine?