Unreal Engine Issues
Unreal Engine Issues
USplineMeshComponent::CalcBounds may return invalid value
USplineMeshComponent::CalcBounds function should be returning an FBoxSphereBounds type, but in the implementation it instead outputs an FBox. This may result in the returning of invalid results, esp ...
FNiagaraStackGraphUtilities::FindScriptModulesInStack() parameter "OutFunctionCalls" should be a reference
UE - Rendering - Architecture - Niagara - Aug 11, 2025On file [Engine\Plugins\FX\Niagara\Source\NiagaraEditor\Public\ViewModels\Stack\NiagaraStackGraphUtilities.h], function FNiagaraStackGraphUtilities::FindScriptModulesInStack() receives a parameter " ...
Occlusion Queries for Static Meshes with ERuntimeVirtualTextureMainPassType::Exclusive
UE - Rendering - Architecture - Feb 20, 2026Static Meshes that draw into RVTs and have "Draw In Main Pass" is set to "From Virtual Texture" (ERuntimeVirtualTextureMainPassType::Exclusive) will still draw in Occlusion Queries. This can be tr ...
Multithreading Race Condition Crash with Anim Montages
OLD - Anim - Apr 2, 2015Basically, the problem is that the Main Thread is able to run AActor::Tick() (including Blueprint Tick Events) at the same time that the animation system is running functions such as UAnimInstance:: ...
Foliage instances don't move with a static mesh when it is shared between two foliage actors
UE - Engine Scaling - Streaming - Foliage - Apr 26, 2023From Licensee: The bug comes from the call of the function `FoliagePartitioningUtils::Update` in the method `AInstancedFoliageActor::MoveInstancesForMovedComponent`. When the function `FoliageParti ...
Re-parenting blueprint actors do not lose interfaces associated with their previous parent blueprint
UE - Gameplay - Blueprint - Jul 23, 2015Re-parenting blueprint actors do not lose interfaces associated with their previous parent blueprint. Interfaces and interface functions can no longer be deleted from the re-parented actor. ...
UKismetStringLibrary::CullArray is poorly implemented
UE - Gameplay - Blueprint - May 18, 2017FString::CullArray is a static function, but the BP version is still taking a string instance to operate on (which it won't mutate as the function is static), and takes the array as an in/out argume ...
r.SupportPointLightWholeSceneShadows Set to False Causes Crash When Trying to Place a PointLight
UE - Graphics Features - Jul 25, 2018If you disable Support PointLightWholeSceneShadows and try to place a point light in a level the editor will crash. Current work around is put shadows to low from engine scalability settings. Wor ...
Uncompressed Lightmaps rendering incorrectly in HTML5
UE - Platform - Mobile - Mar 25, 2015When using uncompressed Lightmaps in HTML5, the lighting is rendered incorrectly. Using (the default) compressed lightmaps, generates no error. Also reproduced in Main Promotable-CL-2487422 (Enscr ...
FOnlineExternalUISteam::ShowWebURL doesn't react correctly to URLs with http:// as the protocol
UE - Networking - Dec 17, 2015Code for this function below:bool FOnlineExternalUISteam::ShowWebURL(const FString& WebURL) { if (!WebURL.StartsWith(TEXT("https://"))) { SteamFriends()->ActivateGameOverlayT ...