Unreal Engine Issues

Landscape.Nanite.MaxSimultaneousMultithreadBuilds hangs indefinitely

It's possible for NaniteStaticMeshesInFlight to never be decremented because all the background workers are waiting indefinitely for the ones in flight to complete their static mesh build.  ...

Landscape Transparent with r.Lumen.DiffuseIndirect.Allow 0

Disabling Disregard for GC with an invalid asset in GameplayTagTableList causes a controlled crash

Disabling Disregard for GC leads to a crash in GarbageCollectionVerification.cpp VerifyObjectFlags. This crash occurs when there is an invalid path specified in GameplayTagTableList. The cause of t ...

Cooker: NeverCookPackageList should store packages as LongPackageNames instead of filenames, to save memory by avoiding creation of FName for each external actor package

GetNeverCookPackageFileNames among other things adds every external actor package to NeverCookPackageList, even if they are not referenced by the rest of the cook. Since it stores the packages in th ...

FILTER_COMMANDLINE_LOGGING cannot be used without forcing UE_COMMAND_LINE_USES_ALLOW_LIST

There's two ways to affect the commandline in CommandLine.cpp: FILTER_COMMANDLINE_LOGGING - for filtering certain or all args (if left empty) from the log. UE_COMMAND_LINE_USES_ALLOW_LIST - for on ...

Physics Linear Velocity functions from UPrimitiveComponent always return (0,0,0) velocity

In Unreal Engine version 5.4, all Physics Linear Velocity functions inside PrimitiveComponent class are returning always a velocity of (0,0,0), even if the Body Instances are moving. This was workin ...

FJsonPointer does not work and may lead to undefined behavior

FJsonPointer::ParsePath passes a pointer to a single TCHAR as FString::ParseIntoArray's pchDelim parameter, which is supposed to be a pointer to a null-terminated string. ...

HideBoneByName translates bone to parent which breaks skinning

Calling HideBoneByName on a bone causes that bone (and all it's children) to be translated to the parent bone's location.  This code in UpdateRefToLocalMatricesInner is responsible: bool bNeedToHid ...

Error when zooming out in orthographic view in 5.4

In 5.4: zooming out far with the mouse wheel after setting the editor viewport to orthgraphic view triggers an ensure: ensure(InOrthoZoom >= MIN_ORTHOZOOM && InOrthoZoom <= MAX_ORTHOZOOM); Th ...

StaticMesh reimport: socket List not refresh if the count is the same