Unreal Engine Issues
Unreal Engine Issues
Iris - actors spawned/loaded before a connection exists will not use delta compression
UE - Networking - Iris - Sep 24, 2025FDeltaCompressionBaselineManager::CreateBaseline will return early if the object has an invalid ObjectInfoIndex, which is allocated in FDeltaCompressionBaselineManager::UpdateScope (by calling FDelt ...
Xcode 26/16.4 Metal Toolchain generates metallib's that are not compatible with iOS 16
UE - Platform - Apple - Sep 23, 2025Below is the error output from FirstPerson template as a C++ project: {+}../../../FirstPerson58CPP/Content/firstperson58cpp_sf_metal_es3_1_ios-metal_es3_1_ios.0.metallib, 5881486 bytes!2025-09-23 1 ...
Ensure when calling server RPC from BeginPlay for a component that is not replicated by default
UE - Networking - Sep 18, 2025This seems to occur due to the order in which the component is registered and set to replicate in UActorComponent::OnCreatedFromReplication. The component is first registered with the world, which c ...
Mover character stuck continuously correcting movement after having a skeletal mesh as movement base
UE - Gameplay - Player Movement - Mover - Sep 8, 2025Once a mover character has had a skeletal mesh set as its movement base, it appears to get stuck in a desynced state after moving to a static movement base. It is only when the character's movement ...
Geometry Collection cluster handles leaking and causing ensures with field systems
UE - Simulation - Visual - Aug 26, 2025Geometry Collection cluster handles leaking and causing ensures with field systems. The licensee has shared their analysis: We have been tracking down an assert that seems to happen occasionally wh ...
Heterogeneous Volume Actor causes ensures to trigger in Debug builds
UE - Niagara - Aug 24, 2025When a heterogeneous volume actor is used with a volume material in a debug build, the following ensures are triggered: Ensure condition failed: UniformBufferValue || EnumHasAnyFlags(AutomaticallyBo ...
ULevelInstanceSubsystem::CreateLevelInstanceFrom() is not honoring parameters bAlwaysShowDialog and LevelPackageName
UE - World Creation - Worldbuilding Tools - Level Instances - Aug 6, 2025A Level Instance or Packed Level Actor can be created through editor scripting by using function ULevelInstanceSubsystem::CreateLevelInstanceFrom(), which receives parameters packed in the FNewLevel ...
Environment Query System (EQS): EnvQuery runtime template object can be created with a non-unique name, corrupting the EnvQueryManager cache
UE - AI - Aug 5, 2025On file [Engine\Source\Runtime\AIModule\Private\EnvironmentQuery\EnvQueryManager.cpp:812], function UEnvQueryManager::CreateQueryInstance() uses StaticDuplicateObject() to create a new UEnvQuery* (d ...
Hardware Raytracing on Lumen can cause a crash on AMD Radeon GPUs
UE - Graphics Features - Lumen - Jul 29, 2025Hardware Raytracing support can cause a crash on AMD Radeon GPUs when creating the RT pipeline state. ...