This is an infrequent but longstanding crash that has occurred since at least UE 4.12.
User Descriptions
Source Context
4202 // See if our existing textures have sufficient space 4203 int32 ExistingTexAvailableChannels = 0; 4204 for (int32 TexIdx = 0; TexIdx < WeightmapTextures.Num(); TexIdx++) 4205 { 4206 FLandscapeWeightmapUsage* Usage = Proxy->WeightmapUsageMap.Find(WeightmapTextures[TexIdx]); 4207 ***** check(Usage); 4208 4209 ExistingTexAvailableChannels += Usage->FreeChannelCount(); 4210 4211 if (ExistingTexAvailableChannels >= NeededNewChannels) 4212 { 4213 break; 4214 } 4215 }
repro steps currently unknown
Assertion failed: Usage [File:D:\Build\++UE4+Release-4.18+Compile\Sync\Engine\Source\Runtime\Landscape\Private\LandscapeEdit.cpp] [Line: 4208] UE4Editor_Landscape!ULandscapeComponent::ReallocateWeightmaps() [landscapeedit.cpp:4208] UE4Editor_Landscape!FLandscapeEditDataInterface::SetAlphaData() [landscapeeditinterface.cpp:2621] UE4Editor_LandscapeEditor!FAlphamapAccessor<1,0>::SetData() [landscapeedmodetools.h:968] UE4Editor_LandscapeEditor!FLandscapeToolStrokePaint::Apply() [landscapeedmodepainttools.cpp:253] UE4Editor_LandscapeEditor!FLandscapeToolBase<FLandscapeToolStrokePaint>::Tick() [landscapeedmodetools.h:1353] UE4Editor_LandscapeEditor!FEdModeLandscape::Tick() [landscapeedmode.cpp:737] UE4Editor_UnrealEd!FEditorModeTools::Tick() [editormodemanager.cpp:716] UE4Editor_UnrealEd!FLevelEditorViewportClient::Tick() [leveleditorviewport.cpp:2072] UE4Editor_UnrealEd!UEditorEngine::Tick() [editorengine.cpp:1734] UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [unrealedengine.cpp:396] UE4Editor!FEngineLoop::Tick() [launchengineloop.cpp:3296] UE4Editor!GuardedMain() [launch.cpp:166] UE4Editor!GuardedMainWrapper() [launchwindows.cpp:134] UE4Editor!WinMain() [launchwindows.cpp:210] UE4Editor!__scrt_common_main_seh() [exe_common.inl:253] kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
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