feat(pawn): Adds OnScaleChanged callback

Source/RWTHVRToolkit/Private/Pawn/RWTHVRPawn.cpp

@@ -42,21 +42,16 @@ ARWTHVRPawn::ARWTHVRPawn(const FObjectInitializer& ObjectInitializer) : Super(Ob
 	LeftHand = CreateDefaultSubobject<UReplicatedMotionControllerComponent>(TEXT("Left Hand MCC"));
 	LeftHand->SetupAttachment(RootComponent);
 
+	UniformScale = GetActorScale3D().X;
 	GetRootComponent()->TransformUpdated.AddLambda([this](USceneComponent*, EUpdateTransformFlags, ETeleportType)
 	{
 		FVector CurrentScale = this->GetActorScale3D();
-		if (CurrentScale.X == CurrentScale.Y && CurrentScale.Y == CurrentScale.Z)
+		if (CurrentScale.X != UniformScale || CurrentScale.Y != UniformScale || CurrentScale.Z != UniformScale)
 		{
-			float expectedScale = GetWorldSettings()->WorldToMeters / InitialWorldToMeters;
-			float ErrorPrecision = 1E-05;
-			if (FMath::IsNearlyEqual(CurrentScale.X, expectedScale, ErrorPrecision))
-			{
-				return;
-			}
-		}
 			UE_LOGFMT(Toolkit, Warning,
 			          "ARWTHVRPawn: Do not adjust the scale of the pawn directly. This will not work in VR. Use ARWTHVRPawn::SetScale(float) instead.")
 			;
+		}
 	});
 }
 
@@ -84,9 +79,17 @@ void ARWTHVRPawn::Tick(float DeltaSeconds)
  */
 void ARWTHVRPawn::SetScale(float NewScale)
 {
-	FVector NewScaleVector = FVector(NewScale, NewScale, NewScale);
-	GetWorldSettings()->WorldToMeters = InitialWorldToMeters * NewScale;
-	SetActorScale3D(NewScaleVector);
+	FVector OldScale = GetActorScale();
+	UniformScale = NewScale;
+	FVector NewScaleVector = FVector(UniformScale, UniformScale, UniformScale);
+	GetWorldSettings()->WorldToMeters = InitialWorldToMeters * UniformScale;
+	SetActorRelativeScale3D(NewScaleVector);
+	OnScaleChanged.Broadcast(OldScale, NewScale);
+}
+
+float ARWTHVRPawn::GetScale()
+{
+	return UniformScale;
 }
 
 /*

Source/RWTHVRToolkit/Public/Pawn/RWTHVRPawn.h

@@ -14,6 +14,8 @@ class UCameraComponent;
 class UMotionControllerComponent;
 struct FLiveLinkTransformStaticData;
 
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_TwoParams(FOnScaleChangedDelegate, FVector, OldScale, float, NewUniformScale);
+
 /**
  * Pawn implementation with additional VR functionality, can be used in the Cave, with an HMD and on desktop.
  */
@@ -34,6 +36,12 @@ public:
 	UFUNCTION(BlueprintCallable)
 	void SetScale(float NewScale);
 
+	UFUNCTION(BlueprintCallable)
+	float GetScale();
+
+	UPROPERTY(BlueprintAssignable)
+	FOnScaleChangedDelegate OnScaleChanged;
+
 	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category = "Pawn|Input")
 	TArray<UInputMappingContext*> InputMappingContexts;
 
@@ -115,4 +123,5 @@ protected:
 private:
 	UInputComponent* ActivePlayerInputComponent;
 	float InitialWorldToMeters;
+	float UniformScale;
 };