Help - Issue sorting TArray with Lambda Predicate

Development Programming & Scripting C++
1

I’m having trouble getting this to compile:

void SortCoverPointsByActorDistance(TArray<AActor*>& CoverPoints, AActor* TargetActor)
{
	CoverPoints.Sort([&TargetActor](const AActor* LHCoverPoint, const AActor* RHCoverPoint) {
		float DistanceToLHCoverPoint = FVector::DistSquared(TargetActor->GetActorLocation(), LHCoverPoint->GetActorLocation());
		float DistanceToRHCoverPoint = FVector::DistSquared(TargetActor->GetActorLocation(), RHCoverPoint->GetActorLocation());

		return DistanceToLHCoverPoint < DistanceToRHCoverPoint;
	});
}

I keep getting this error:

|Error|C2664|‘bool USBTTaskNode_Hide::SortCoverPointsByActorDistance::<lambda_5f025693871c2d5affd9a2f93dd13701>::operator ()(const AActor *&,const AActor *&) const’: cannot convert argument 1 from ‘T’ to ‘const AActor *&’|ActionRoguelike|C:\Program Files\Epic Games\UE_4.27\Engine\Source\Runtime\Core\Public\Templates\Sorting.h|38||

Any ideas?

2

Sort is kinda weird as it derefences pointers.

To fix your issue, use this:

void SortCoverPointsByActorDistance(TArray<AActor*>& CoverPoints, AActor* TargetActor)
{
	CoverPoints.Sort([TargetActor](const AActor& LHCoverPoint, const AActor& RHCoverPoint) {
		float DistanceToLHCoverPoint = FVector::DistSquared(TargetActor->GetActorLocation(), LHCoverPoint->GetActorLocation());
		float DistanceToRHCoverPoint = FVector::DistSquared(TargetActor->GetActorLocation(), RHCoverPoint->GetActorLocation());

		return DistanceToLHCoverPoint < DistanceToRHCoverPoint;
	});
}