Movie Pipeline crashing due to "An incorrect or uninitialized time step was used! Delta Time of 0 isn't allowed."

Development Cinematics & Media
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1

Hey guys,

We are experiencing some mysterious crashes when using movie render queue at runtime in 5.2.1. Once we generated some frames with it at runtime, our app keeps working properly, up until another sublevel loaded or some data downloaded. Then it produces a crash with the following error message. Has anyone experienced anything similar or it is an engine bug? Note that at the moment of crash, the movie pipeline is NOT being used. It is happening minutes or even 30 minutes after the movie pipeline was used.

[2023.09.02-04.40.09:886][342]LogMovieRenderPipeline: Error: Too many temporal samples for the given shutter angle/tick rate combination. Temporal Samples: 3 Shutter Angle: 0.000000 TicksPerOutputFrame: Frame: 800 Subframe: 0.000000 TicksPerSample: Frame: 0 Subframe: 0.740741. Consider converting to Spatial Samples instead!
[2023.09.02-04.40.09:886][342]LogOutputDevice: Warning:

Script Stack (0 frames) :

[2023.09.02-04.40.10:422][342]LogStats: FPlatformStackWalk::StackWalkAndDump - 0.537 s
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: === Handled ensure: ===
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error:
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: Ensure condition failed: !FMath::IsNearlyZero(InTimeCache.UndilatedDeltaTime) [File:D:\build++UE5\Sync\Engine\Plugins\MovieScene\MovieRenderPipeline\Source\MovieRenderPipelineCore\Private\MoviePipeline.cpp] [Line: 855]
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: An incorrect or uninitialized time step was used! Delta Time of 0 isn’t allowed.
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: Stack:
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff632667afd RDesignV3.exe!UMoviePipelineCustomTimeStep::SetCachedFrameTiming()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff6326747be RDesignV3.exe!UMoviePipeline::TickProducingFrames()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff632651fad RDesignV3.exe!UMoviePipeline::OnEngineTickBeginFrame()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff632635e21 RDesignV3.exe!TBaseUObjectMethodDelegateInstance<0,UMoviePipeline,void __cdecl(void),FDefaultDelegateUserPolicy>::ExecuteIfSafe()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff631a56df6 RDesignV3.exe!TMulticastDelegate<void __cdecl(void),FDefaultDelegateUserPolicy>::Broadcast()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff631a438cc RDesignV3.exe!FEngineLoop::Tick()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff631a6201c RDesignV3.exe!GuardedMain()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff631a620fa RDesignV3.exe!GuardedMainWrapper()
[2023.09.02-04.40.10:422][342]LogOutputDevice: Error: [Callstack] 0x00007ff631a65006 RDesignV3.exe!LaunchWindowsStartup()
[2023.09.02-04.40.10:423][342]LogOutputDevice: Error: [Callstack] 0x00007ff631a77d34 RDesignV3.exe!WinMain()
[2023.09.02-04.40.10:423][342]LogOutputDevice: Error: [Callstack] 0x00007ff63c34d68a RDesignV3.exe!__scrt_common_main_seh() [D:\a_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
[2023.09.02-04.40.10:423][342]LogOutputDevice: Error: [Callstack] 0x00007ff8f33a26ad KERNEL32.DLL!UnknownFunction
[2023.09.02-04.40.10:423][342]LogOutputDevice: Error: [Callstack] 0x00007ff8f490aa68 ntdll.dll!UnknownFunction
[2023.09.02-04.40.10:423][342]LogOutputDevice: Error:
[2023.09.02-04.40.10:431][342]LogStats: SubmitErrorReport - 0.000 s

2

Also, we are downloading some content at runtime and it is working perfectly well, until we use the movie pipeline subsystem, then it is also causing crashes when trying to mount the content. If we do not use the movie pipeline system to render screenshots, the app is working perfectly without crashes.
Here is the error code we get:

[2023.09.02-09.54.15:056][764]LogWindows: Error: === Critical error: ===
[2023.09.02-09.54.15:056][764]LogWindows: Error:
[2023.09.02-09.54.15:056][764]LogWindows: Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0xffffffffffffffff
[2023.09.02-09.54.15:056][764]LogWindows: Error:
[2023.09.02-09.54.15:056][764]LogWindows: Error: [Callstack] 0x00007ffbc3e73536 ntdll.dll!UnknownFunction
[2023.09.02-09.54.15:056][764]LogWindows: Error: [Callstack] 0x00007ffbc3e3fcb4 ntdll.dll!UnknownFunction
[2023.09.02-09.54.15:056][764]LogWindows: Error: [Callstack] 0x00007ffbc3e3fae2 ntdll.dll!UnknownFunction
[2023.09.02-09.54.15:056][764]LogWindows: Error: [Callstack] 0x00007ff7d70350e6 RDesignV3.exe!<lambda_c17a97dc1c1d90988a4931a380ba6d79>::operator()()
[2023.09.02-09.54.15:056][764]LogWindows: Error: [Callstack] 0x00007ff7d706e3ed RDesignV3.exe!TBaseRawMethodDelegateInstance<0,FSystemSettings,void __cdecl(void),FDefaultDelegateUserPolicy>::Execute()
[2023.09.02-09.54.15:056][764]LogWindows: Error: [Callstack] 0x00007ff7d5988679 RDesignV3.exe!FPakPlatformFile::Mount()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d117e31e RDesignV3.exe!UBaseBlueprintFunctionLibrary::MountPakFile() [D:\Git_Repos\roommaker_gen2\RDesign\Source\RDesignV3\BaseBlueprintFunctionLibrary.cpp:1211]
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d116c97e RDesignV3.exe!UAPI_ChunkDownloaderSystem::HandleAPIResponse() [D:\Git_Repos\roommaker_gen2\RDesign\Source\RDesignV3\API\API_ChunkDownloaderSystem.cpp:282]
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d1157036 RDesignV3.exe!TBaseUObjectMethodDelegateInstance<0,UAPI_ChunkDownloaderSystem,void __cdecl(TSharedPtr<IHttpRequest,1>,TSharedPtr<IHttpResponse,1>,bool),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\UE_5.2\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:552]
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d1d6b128 RDesignV3.exe!TDelegate<void __cdecl(TSharedPtr<IHttpRequest,1>,TSharedPtr<IHttpResponse,1>,bool),FDefaultDelegateUserPolicy>::ExecuteIfBound<void,0>()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d1d78b45 RDesignV3.exe!FCurlHttpRequest::FinishedRequest()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d1d9771b RDesignV3.exe!FHttpManager::Tick()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d12bd455 RDesignV3.exe!TBaseRawMethodDelegateInstance<0,FTSTickerObjectBase,bool __cdecl(float),FDefaultDelegateUserPolicy>::Execute()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d12c7969 RDesignV3.exe!FTSTicker::Tick()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d12532c2 RDesignV3.exe!<lambda_06f0dd4e3c6d48b8b92481d32d031cdc>::operator()()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d12bd3ce RDesignV3.exe!TBaseFunctorDelegateInstance<bool __cdecl(float),FDefaultDelegateUserPolicy,TFunction<bool __cdecl(float)> >::Execute()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d12c7969 RDesignV3.exe!FTSTicker::Tick()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7ce039e49 RDesignV3.exe!FEngineLoop::Tick()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7ce05201c RDesignV3.exe!GuardedMain()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7ce0520fa RDesignV3.exe!GuardedMainWrapper()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7ce055006 RDesignV3.exe!LaunchWindowsStartup()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7ce067d34 RDesignV3.exe!WinMain()
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ff7d893d68a RDesignV3.exe!__scrt_common_main_seh() [D:\a_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ffbc3b57614 KERNEL32.DLL!UnknownFunction
[2023.09.02-09.54.15:057][764]LogWindows: Error: [Callstack] 0x00007ffbc3e626b1 ntdll.dll!UnknownFunction
[2023.09.02-09.54.15:057][764]LogWindows: Error:
[2023.09.02-09.54.15:060][764]LogExit: Executing StaticShutdownAfterError
[2023.09.02-09.54.15:063][764]LogWindows: FPlatformMisc::RequestExit(1)
[2023.09.02-09.54.15:063][764]LogWindows: FPlatformMisc::RequestExitWithStatus(1, 3)
[2023.09.02-09.54.15:063][764]LogCore: Engine exit requested (reason: Win RequestExit)

3

From the error messages, I would guess that it has something to do with the delegates or the tick function, since the crash is happening on the “ExecuteIfSafe()” functions.

4

The crash is occuring when the FCoreDelegates::OnPakFileMounted2.Broadcast() is called in our case.

5

But as stated earlier too, this only happens after using the movie render queue. Before that, it works perfectly. Once we use the movie render queue for some runtime rendering, the crash occurs the next time the delegate is called.

6

FYI, I could reproduce this issue in a clean project too. Anyone can access it on this google drive link, both the project and the packaged build. All it does is it allocates a render job 5 seconds after the startup, renders the sequence and 1 second later it tries to mount a pak content file from /Saved/PersistentDownloadDir/pakchunk1-Windows.pak path. You can press the Z key to try to mount the file before the render job starts, you can see that it works and mount the content properly. But if you do the same after the render job, now it crashes.

https://drive.google.com/drive/folders/1wxu80XGQL4z2D_DsbI4epqtOOjp2QskS?usp=drive_link

7

5.3 engine version seems to be not affected by this issue, at least not in a clean project.