UCollisionProfile::ConvertToCollisionChannel does not behave as expected

Development World Creation
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1

Hello, I’m currently working with custom object types for collision and I’ve found something really weird in the source code of UCollisionProfile::ConvertToCollisionChannel.

ECollisionChannel UCollisionProfile::ConvertToCollisionChannel(bool TraceType, int32 Index) const
{
	if (TraceType)
	{
		if ( TraceTypeMapping.IsValidIndex(Index) )
		{
			return TraceTypeMapping[Index];
		}
	}
	else
	{
		if ( ObjectTypeMapping.IsValidIndex(Index) )
		{
			return ObjectTypeMapping[Index];
		}
	}

	// invalid
	return ECC_MAX;
}

It came from a call to SphereOverlapActors which is given a
const TArray<TEnumAsByte<EObjectTypeQuery> > & ObjectTypes

this will take the EObjectTypeQuery as an int and give it to UCollisionProfile::ConvertToCollisionChannel. The problem is that ObjectTypeMapping does not look like EObjectTypeQuery, so it is impossible that ObjectTypeMapping[Index] returns the good ECollisionChannel.

For example if you give ECC_PhysicBody to the function SphereOverlapActors, it will be converted to the ECollisionChannel ECC_Destructible.

I found this not normal at all, but I’m not very good with unreal collision yet, so maybe I’m using it wrong.