Editor crash will occur when a user attempts to enter the Mesh Paint, Landscape, or Foliage modes while Simulating.
Links to CrashReporter:
Foliage: [Link Removed]
Landscape: [Link Removed]
Mesh Paint: [Link Removed]
Regression: Yes
Working: 4.14.3 Binary
Broken: 4.15 Release & 4.16 Main
Update from quick debug (chris.wood):
In this line
UVREditorMode* VREditorMode = GEditor->GetEditorWorldManager()->GetEditorWorldWrapper( Viewport->GetClient()->GetWorld() )->GetVREditorMode();
GetEditorWorldWrapper() returns null because the World is PIE in FEditorWorldManager::OnWorldContextAdd(). So we call GetVREditorMode() on null ptr.
Line was added in CL 3109859 by Yannick.Lange
RESULT:
Editor will crash upon clicking to enter either Mesh Paint, Landscape, or Foliage modes.
Assertion failed: IsValid() [File:D:\Builds\UE4-Main\Engine\Source\Runtime\Core\Public\Templates/SharedPointer.h]
EXPECTED RESULT:
Either the buttons are blocked from being selected, or the user can successfully enter the Foliage, Mesh Paint, and Landscape modes while Simulating.
Assertion failed: IsValid() [File:D:\Builds\UE4-Main\Engine\Source\Runtime\Core\Public\Templates/SharedPointer.h] UE4Editor_LandscapeEditor!FEdModeLandscape::Enter() landscapeedmode.cpp:478 UE4Editor_UnrealEd!FEditorModeTools::ActivateMode() editormodemanager.cpp:384 UE4Editor_LevelEditor!SLevelEditor::ToggleEditorMode() sleveleditor.cpp:1238 UE4Editor_LevelEditor!TBaseStaticDelegateInstance<void __cdecl() delegateinstancesimpl.h:1027 UE4Editor_Slate!FUICommandList::ExecuteAction() uicommandlist.cpp:97 UE4Editor_Slate!SToolBarButtonBlock::OnClicked() stoolbarbuttonblock.cpp:305 UE4Editor_Slate!SToolBarButtonBlock::OnCheckStateChanged() stoolbarbuttonblock.cpp:330 UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SToolBarButtonBlock,0,TTypeWrapper<void> __cdecl() delegateinstancesimpl.h:327 UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SToolBarButtonBlock,0,void __cdecl() delegateinstancesimpl.h:434 UE4Editor_Slate!SCheckBox::ToggleCheckedState() scheckbox.cpp:299 UE4Editor_Slate!SCheckBox::OnMouseButtonUp() scheckbox.cpp:190 UE4Editor_Slate!<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1>::operator() slateapplication.cpp:5052 UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1> >() slateapplication.cpp:238 UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() slateapplication.cpp:5041 UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() slateapplication.cpp:5504 UE4Editor_Slate!FSlateApplication::OnMouseUp() slateapplication.cpp:5481 UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() windowsapplication.cpp:1698 UE4Editor_Core!FWindowsApplication::DeferMessage() windowsapplication.cpp:2120 UE4Editor_Core!FWindowsApplication::ProcessMessage() windowsapplication.cpp:867 UE4Editor_Core!FWindowsApplication::AppWndProc() windowsapplication.cpp:714 user32!<Unknown> user32!<Unknown> UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() windowsplatformmisc.cpp:979 UE4Editor!FEngineLoop::Tick() launchengineloop.cpp:2971 UE4Editor!GuardedMain() launch.cpp:166 UE4Editor!GuardedMainWrapper() launchwindows.cpp:130 UE4Editor!WinMain() launchwindows.cpp:206 UE4Editor!__scrt_common_main_seh() exe_common.inl:264 kernel32!<Unknown> ntdll!<Unknown>
Update chris.wood
Same repro and error message but different callstack here (running Debug Editor)
UE4Editor-MeshPaint-Win64-Debug.dll!FEdModeMeshPaint::Render(const FSceneView * View, FViewport * Viewport, FPrimitiveDrawInterface * PDI) Line 2752 UE4Editor-UnrealEd-Win64-Debug.dll!FEditorModeTools::Render(const FSceneView * InView, FViewport * Viewport, FPrimitiveDrawInterface * PDI) Line 800 UE4Editor-UnrealEd-Win64-Debug.dll!FEditorViewportClient::Draw(const FSceneView * View, FPrimitiveDrawInterface * PDI) Line 3507 UE4Editor-UnrealEd-Win64-Debug.dll!FLevelEditorViewportClient::Draw(const FSceneView * View, FPrimitiveDrawInterface * PDI) Line 3925 UE4Editor-Renderer-Win64-Debug.dll!FSceneRenderer::FSceneRenderer(const FSceneViewFamily * InViewFamily, FHitProxyConsumer * HitProxyConsumer) Line 1153 UE4Editor-Renderer-Win64-Debug.dll!FDeferredShadingSceneRenderer::FDeferredShadingSceneRenderer(const FSceneViewFamily * InViewFamily, FHitProxyConsumer * HitProxyConsumer) Line 194 UE4Editor-Renderer-Win64-Debug.dll!FSceneRenderer::CreateSceneRenderer(const FSceneViewFamily * InViewFamily, FHitProxyConsumer * HitProxyConsumer) Line 1453 UE4Editor-Renderer-Win64-Debug.dll!FRendererModule::BeginRenderingViewFamily(FCanvas * Canvas, FSceneViewFamily * ViewFamily) Line 1868 UE4Editor-UnrealEd-Win64-Debug.dll!FEditorViewportClient::Draw(FViewport * InViewport, FCanvas * Canvas) Line 3379 UE4Editor-Engine-Win64-Debug.dll!FViewport::Draw(bool bShouldPresent) Line 1185 UE4Editor-UnrealEd-Win64-Debug.dll!UEditorEngine::UpdateSingleViewportClient(FEditorViewportClient * InViewportClient, const bool bInAllowNonRealtimeViewportToDraw, bool bLinkedOrthoMovement) Line 2007 UE4Editor-UnrealEd-Win64-Debug.dll!UEditorEngine::Tick(float DeltaSeconds, bool bIdleMode) Line 1755 UE4Editor-UnrealEd-Win64-Debug.dll!UUnrealEdEngine::Tick(float DeltaSeconds, bool bIdleMode) Line 391 UE4Editor-Win64-Debug.exe!FEngineLoop::Tick() Line 3025 UE4Editor-Win64-Debug.exe!EngineTick() Line 63 UE4Editor-Win64-Debug.exe!GuardedMain(const wchar_t * CmdLine, HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, int nCmdShow) Line 169 UE4Editor-Win64-Debug.exe!GuardedMainWrapper(const wchar_t * CmdLine, HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, int nCmdShow) Line 130 UE4Editor-Win64-Debug.exe!WinMain(HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, char * __formal, int nCmdShow) Line 206
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-40528 in the post.