Project World to Screen Location stops returning a value

Development Programming & Scripting Blueprint
11

Just an update for anyone not getting this to work in UE5.

Code for the .h

UFUNCTION(BlueprintPure, Category = "UI Math")
static bool ProjectWorldToScreenBidirectional(APlayerController const* Player, const FVector& WorldPosition, FVector2D& ScreenPosition, bool& bTargetBehindCamera, bool bPlayerViewportRelative = false);

Code for the .cpp

bool UIBlueprintFunctionLibrary::ProjectWorldToScreenBidirectional(APlayerController const* Player, const FVector& WorldPosition, FVector2D& ScreenPosition, bool& bTargetBehindCamera, bool bPlayerViewportRelative)
{
	FVector Projected;
	bool bSuccess = false;

	ULocalPlayer* const LP = Player ? Player->GetLocalPlayer() : nullptr;
	if (LP && LP->ViewportClient)
	{
		// get the projection data
		FSceneViewProjectionData ProjectionData;
		if (LP->GetProjectionData(LP->ViewportClient->Viewport, /*out*/ ProjectionData))
		{
			const FMatrix ViewProjectionMatrix = ProjectionData.ComputeViewProjectionMatrix();
			const FIntRect ViewRectangle = ProjectionData.GetConstrainedViewRect();

			FPlane Result = ViewProjectionMatrix.TransformFVector4(FVector4(WorldPosition, 1.f));
			if (Result.W < 0.f) { bTargetBehindCamera = true; } else { bTargetBehindCamera = false; }
			if (Result.W == 0.f) { Result.W = 1.f; } // Prevent Divide By Zero

			const float RHW = 1.f / FMath::Abs(Result.W);
			Projected = FVector(Result.X, Result.Y, Result.Z) * RHW;

			// Normalize to 0..1 UI Space
			const float NormX = (Projected.X / 2.f) + 0.5f;
			const float NormY = 1.f - (Projected.Y / 2.f) - 0.5f;

			Projected.X = (float)ViewRectangle.Min.X + (NormX * (float)ViewRectangle.Width());
			Projected.Y = (float)ViewRectangle.Min.Y + (NormY * (float)ViewRectangle.Height());

			bSuccess = true;
			ScreenPosition = FVector2D(Projected.X, Projected.Y);

			if (bPlayerViewportRelative)
			{
				ScreenPosition -= FVector2D(ProjectionData.GetConstrainedViewRect().Min);
			}
		}
		else
		{
			ScreenPosition = FVector2D(1234, 5678);
		}
	}

	return bSuccess;
}

Changed:

if (LP->GetProjectionData(LP->ViewportClient->Viewport, eSSP_FULL, /*out*/ ProjectionData))

To

if (LP->GetProjectionData(LP->ViewportClient->Viewport, /*out*/ ProjectionData))

And added Daniel_Alves_br’s suggestion.

I suggest you to add na ELSE parameter to set bTargetBehindCamera back to false when look to the tag point again.

if (Result.W < 0.f) { bTargetBehindCamera = true; } else {bTargetBehindCamera = false;}
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