Sequencer, Fade and Last Tick Bug

Development Cinematics & Media
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1

Hi!

I found bug, or strange behavior of Sequencer Player.

  • Create Empty C++ Project.

  • Create Level Sequence. And add it to the Current Level.

  • Add Fade track, and set fade from 0 to 1 (cinematic must finish with full faded screen).

  • Modify Game Mode header file like this:

     UCLASS()
 class SEQUENCERLASTFRAME_API ASequencerLastFrameGameModeBase : public AGameModeBase
 {
     GENERATED_BODY()

 public:

     UPROPERTY(Transient)
     class ALevelSequenceActor* cinematic;
         
 public:
     
     virtual void StartPlay() override;

     UFUNCTION()
     void OnCinematicStop();
 };

  • Modify Game Mode source file like this:

     void ASequencerLastFrameGameModeBase::StartPlay()
 {
 	Super::StartPlay();

 	TActorIterator<ALevelSequenceActor> It(GetWorld());
 	if (It)
 		cinematic = *It;

 	if (IsValid(cinematic))
 	{
 		cinematic->SequencePlayer->OnStop.AddDynamic(this, &ThisClass::OnCinematicStop);
 		cinematic->SequencePlayer->SetPlaybackPosition(0.0f);
 		cinematic->SequencePlayer->Play();
 	}
 }

 void ASequencerLastFrameGameModeBase::OnCinematicStop()
 {
 	auto It = GetWorld()->GetPlayerControllerIterator();
 	if (auto PC = *It)
 	{
 		PC->PlayerCameraManager->StartCameraFade(1.0f, 0.0f, 1.0f, FLinearColor::Black, false, true);
 		GEngine->AddOnScreenDebugMessage(-1, 5.0f, FColor::Red, TEXT("CameraFade called, but nothing happened!"));
 	}
 	else 
 		GEngine->AddOnScreenDebugMessage(-1, 5.0f, FColor::Red, TEXT("PC not found!"));
 }

  • Don’t forget to add “LevelSequence” to build.cs.

  • Compile and start play.

We see black screen and text “CameraFade called, but nothing happened!” in the left top corner. Looks like function SetManualCameraFade called one more time in FMovieSceneFadeTrackInstance::Update after the OnStop delegate called.

Project with bug you can find here:
https://github.com/maltsevda/SequencerLastFrame

2

If we add delay in 0.1 sec, before calling StartCameraFade, all works fine. Hope you can fix this in next releases! :slight_smile:

3

Hey rionix,

Your issue no longer appears to happen in 4.15. I upgraded your project to 4.15 and it worked as expected. Thanks for reporting this though!