Engine crashes when trying to move key in UMG animation

anonymous_user_0757868c · October 14, 2016, 2:11pm

Not sure if this happens in 4.13 as I haven’t updated, but in UMG animations, if you try to grab a key on the animation timeline to move it (not the curve editor, the basic timeline), it crashes the engine. Here’s the crash stack trace for convenience:

MachineId:
EpicAccountId:

Assertion failed: Struct->Keys[Index] != nullptr [File:G:\Program Files\Epic Games\UnrealEngine-4.12 Source\Engine\Source\Runtime\MovieSceneTracks\Private\Sections\MovieSceneColorSection.cpp] [Line: 124] 



UE4Editor_Core!FDebug::AssertFailed() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\core\private\misc\outputdevice.cpp:440]
UE4Editor_MovieSceneTracks!UMovieSceneColorSection::GetKeyStruct() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\moviescenetracks\private\sections\moviescenecolorsection.cpp:125]
UE4Editor_Sequencer!FGroupedKeyArea::GetKeyStruct() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\groupedkeyarea.cpp:658]
UE4Editor_Sequencer!FKeyContextMenu::CanAddPropertiesMenu() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\sequencercontextmenus.cpp:169]
UE4Editor_Sequencer!FKeyContextMenu::PopulateMenu() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\sequencercontextmenus.cpp:39]
UE4Editor_Sequencer!FKeyContextMenu::BuildMenu() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\sequencercontextmenus.cpp:30]
UE4Editor_Sequencer!SequencerHelpers::SummonContextMenu() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\sequencercommonhelpers.cpp:368]
UE4Editor_Sequencer!FSequencerEditTool_Movement::OnMouseButtonUp() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\tools\sequenceredittool_movement.cpp:215]
UE4Editor_Sequencer!FSequencerInputHandlerStack::ProcessEvent() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\sequencerinputhandlerstack.h:96]
UE4Editor_Sequencer!FSequencerInputHandlerStack::HandleMouseButtonUp() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\sequencerinputhandlerstack.h:55]
UE4Editor_Sequencer!SSequencerTrackArea::OnMouseButtonUp() [g:\program files\epic games\unrealengine-4.12 source\engine\source\editor\sequencer\private\ssequencertrackarea.cpp:214]
UE4Editor_Slate!<lambda_2ba86970cc12b39cc598727b6025bd91>::operator()() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4598]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_2ba86970cc12b39cc598727b6025bd91> >() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:215]
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4587]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5041]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5021]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\core\private\windows\windowsapplication.cpp:1510]
UE4Editor_Core!FWindowsApplication::DeferMessage() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\core\private\windows\windowsapplication.cpp:1850]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\core\private\windows\windowsapplication.cpp:745]
UE4Editor_Core!FWindowsApplication::AppWndProc() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\core\private\windows\windowsapplication.cpp:667]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:903]
UE4Editor!FEngineLoop::Tick() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\launch\private\launchengineloop.cpp:2729]
UE4Editor!GuardedMain() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\launch\private\launch.cpp:148]
UE4Editor!GuardedMainWrapper() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [g:\program files\epic games\unrealengine-4.12 source\engine\source\runtime\launch\private\windows\launchwindows.cpp:200]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll

anonymous_user_e729f54e · October 14, 2016, 5:20pm

Hello Rael5,

I am unable to reproduce this issue on our end. I have a few questions for you that will help narrow down what issue it is that you are experiencing.

Quick questions:

Can you reproduce this issue in a clean project?
If so, could you provide a detailed list of steps to reproduce this issue on our end?
Could you provide screen shots of any widgets/blueprints that may be involved with this issue?

anonymous_user_0757868c · October 15, 2016, 12:37pm

I tried it with a blank project. I realized after the fact that what had caused the crash was holding in right click as well, because i remember the grab icon appearing right when it crashed. I tried a combination of left clicking the key and right clicking at different times/locations. I was able to reproduce the crash twice, but I’m not sure the exact circumstances that made it happen. In either case, these are the steps I took:

Create blank project
Create UMG widget
Add image to canvas
Create new animation
Create some keys for the animation, any type, at different times
Try different combinations of left clicking, right clicking and dragging on the keys, letting go of the clicks on/off the timeline or on/off other keys

anonymous_user_e729f54e · October 17, 2016, 3:55pm

Hello Rael5,

Thank you for the additional information, however I am still unable to reproduce this issue with the information provided. Could you provide the project that is having the crash so that I could take a closer look?

anonymous_user_e729f54e · October 20, 2016, 3:57pm

Hello Rael5,

We have not heard back from you in a few days, so we are marking this post as Resolved for tracking purposes. If you are still experiencing the issue you reported, please respond to this message with additional information and we will follow up.

Thanks,