Changing Navmesh Walkable slope in project settings crashes editor

I was trying to set the navmesh walkable slope setting in the editor project settings. I get a crash.

I can at least set it in DefaultEngine.ini under

[/Script/Engine.RecastNavMesh]
AgentMaxSlope=45

I’m running the editor through visual studio so I can see the stack trace and breakpoints.

Seems like the this pointer on the UNavigationSystem object is NULL.

UE4Editor-Engine-Win64-Debug.dll!UNavigationSystem::GetSupportedAgentIndex(const ANavigationData * NavData) Line 1576 C++
UE4Editor-Engine-Win64-Debug.dll!FRecastNavMeshGenerator::Init() Line 2779 C++
UE4Editor-Engine-Win64-Debug.dll!FRecastNavMeshGenerator::FRecastNavMeshGenerator(ARecastNavMesh * InDestNavMesh) Line 2718 C++
UE4Editor-Engine-Win64-Debug.dll!ARecastNavMesh::ConstructGenerator() Line 1743 C++
UE4Editor-Engine-Win64-Debug.dll!ANavigationData::RebuildAll() Line 363 C++
UE4Editor-Engine-Win64-Debug.dll!ARecastNavMesh::PostEditChangeProperty(FPropertyChangedEvent & PropertyChangedEvent) Line 1710 C++
UE4Editor-CoreUObject-Win64-Debug.dll!UObject::PostEditChangeChainProperty(FPropertyChangedChainEvent & PropertyChangedEvent) Line 264 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!FPropertyNode::NotifyPostChange(FPropertyChangedEvent & InPropertyChangedEvent, FNotifyHook * InNotifyHook) Line 1906 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!FPropertyValueImpl::ImportText(const TArray<FObjectBaseAddress,FDefaultAllocator> & InObjects, const TArray<FString,FDefaultAllocator> & InValues, FPropertyNode * InPropertyNode, unsigned int Flags) Line 427 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!FPropertyValueImpl::ImportText(const FString & InValue, FPropertyNode * InPropertyNode, unsigned int Flags) Line 282 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!FPropertyValueImpl::ImportText(const FString & InValue, unsigned int Flags) Line 184 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!FPropertyHandleFloat::SetValue(const float & NewValue, unsigned int Flags) Line 2110 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!SPropertyEditorNumeric::OnValueCommitted(float NewValue, ETextCommit::Type CommitInfo) Line 224 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!TBaseSPMethodDelegateInstance<0,SPropertyEditorNumeric,0,TTypeWrapper __cdecl(float,enum ETextCommit::Type)>::Execute(float <Params_0>, ETextCommit::Type <Params_1>) Line 283 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!TBaseSPMethodDelegateInstance<0,SPropertyEditorNumeric,0,void __cdecl(float,enum ETextCommit::Type)>::ExecuteIfSafe(float <Params_0>, ETextCommit::Type <Params_1>) Line 383 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!SSpinBox::CommitValue(double NewValue, SSpinBox::ECommitMethod CommitMethod, ETextCommit::Type OriginalCommitInfo) Line 627 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!SSpinBox::TextField_OnTextCommitted(const FText & NewText, ETextCommit::Type CommitInfo) Line 557 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!TBaseSPMethodDelegateInstance<0,SSpinBox,0,TTypeWrapper __cdecl(FText const & __ptr64,enum ETextCommit::Type)>::Execute(const FText & <Params_0>, ETextCommit::Type <Params_1>) Line 283 C++
UE4Editor-PropertyEditor-Win64-Debug.dll!TBaseSPMethodDelegateInstance<0,SSpinBox,0,void __cdecl(FText const & __ptr64,enum ETextCommit::Type)>::ExecuteIfSafe(const FText & <Params_0>, ETextCommit::Type <Params_1>) Line 383 C++
UE4Editor-Slate-Win64-Debug.dll!SEditableText::OnEnter() Line 974 C++
UE4Editor-Slate-Win64-Debug.dll!FTextEditHelper::OnKeyDown(const FKeyEvent & InKeyEvent, const TSharedRef<ITextEditorWidget,0> & TextEditor) Line 165 C++
UE4Editor-Slate-Win64-Debug.dll!SEditableText::OnKeyDown(const FGeometry & MyGeometry, const FKeyEvent & InKeyEvent) Line 1629 C++
UE4Editor-Slate-Win64-Debug.dll!FSlateApplication::ProcessKeyDownEvent::__l18::(const FArrangedWidget & SomeWidgetGettingEvent, const FKeyEvent & Event) Line 3468 C++
UE4Editor-Slate-Win64-Debug.dll!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FKeyEvent,FReply (const FArrangedWidget &, const FKeyEvent &) >(FSlateApplication * ThisApplication, FEventRouter::FBubblePolicy RoutingPolicy, FKeyEvent EventCopy, const FSlateApplication::ProcessKeyDownEvent::__l18::FReply (const FArrangedWidget &, const FKeyEvent &) & Lambda) Line 208 C++
UE4Editor-Slate-Win64-Debug.dll!FEventRouter::RouteAlongFocusPath<FEventRouter::FBubblePolicy,FReply (const FArrangedWidget &, const FKeyEvent &),FKeyEvent>(FSlateApplication * ThisApplication, FEventRouter::FBubblePolicy RoutingPolicy, FKeyEvent KeyEventCopy, const FSlateApplication::ProcessKeyDownEvent::l18::FReply (const FArrangedWidget &, const FKeyEvent &) & Lambda) Line 190 C++
UE4Editor-Slate-Win64-Debug.dll!FSlateApplication::ProcessKeyDownEvent(FKeyEvent & InKeyEvent) Line 3469 C++
UE4Editor-Slate-Win64-Debug.dll!FSlateApplication::OnKeyDown(const int KeyCode, const unsigned int CharacterCode, const bool IsRepeat) Line 3410 C++
UE4Editor-Core-Win64-Debug.dll!FWindowsApplication::ProcessDeferredMessage(const FDeferredWindowsMessage & DeferredMessage) Line 1214 C++
UE4Editor-Core-Win64-Debug.dll!FWindowsApplication::DeferMessage(TSharedPtr<FWindowsWindow,0> & NativeWindow, HWND
* InHWnd, unsigned int InMessage, unsigned int64 InWParam, int64 InLParam, int MouseX, int MouseY, unsigned int RawInputFlags) Line 1657 C++
UE4Editor-Core-Win64-Debug.dll!FWindowsApplication::ProcessMessage(HWND
* hwnd, unsigned int msg, unsigned int64 wParam, int64 lParam) Line 744 C++
UE4Editor-Core-Win64-Debug.dll!FWindowsApplication::AppWndProc(HWND
* hwnd, unsigned int msg, unsigned int64 wParam, int64 lParam) Line 603 C++
[External Code]
UE4Editor-Core-Win64-Debug.dll!WinPumpMessages() Line 752 C++
UE4Editor-Core-Win64-Debug.dll!FWindowsPlatformMisc::PumpMessages(bool bFromMainLoop) Line 779 C++
UE4Editor-Win64-Debug.exe!FEngineLoop::Tick() Line 2193 C++
UE4Editor-Win64-Debug.exe!EngineTick() Line 52 C++
UE4Editor-Win64-Debug.exe!GuardedMain(const wchar_t * CmdLine, HINSTANCE
* hInInstance, HINSTANCE
* hPrevInstance, int nCmdShow) Line 134 C++
UE4Editor-Win64-Debug.exe!WinMain(HINSTANCE
* hInInstance, HINSTANCE
* hPrevInstance, char * __formal, int nCmdShow) Line 191 C++
[External Code]

Which UE4 version are you using?

This is a known issue that has been fixed in 4.7 (out soon, you can grab a preview build now if you’re inpatient :D)

Cheers,

–mieszko

Oh nice, I’m on 4.6.1