Unreal Engine Issues

After attach a component to a simulated component by socket miss collisions

If attaches a StaticMeshComponent with collision active to another actor with a SkeletalMeshComponent simulating physics by socket name the StaticMeshComponent miss collision for simulation. Chec ...

Third person camera lag issue for vehicle in multiplayer

There's a vehicle/third person camera stutter observed as the vehicle corners. The issue appears worse with Physics Async mode enabled, and less perceptible with this mode disabled. This video was ...

Check in SetNetPushIdDynamic fails when deriving object from class with no replicated properties

UHT will only emit the REPLICATED_BASE_CLASS macro and set the NeedsPushModelHeaders flag when the class has replicated properties. If a base class doesn't have any replicated properties, it will le ...

Long thin spinning objects take too long to stop spinning

See the SpinningObjectStability test map in the Physics Sandbox. [Link Removed] It's not clear if this is a bug or a side effect of some of our solver shortcuts (e.g., omission of the precession te ...

Objects without custom delta properties can return false for CanSkipUpdate with net.PushModelSkipUndirtiedReplication enabled

This seems to occur after receiving a Nak for certain actors. FObjectReplicator::ReceivedNak will decrement SendingRepState.CustomDeltaChangeIndex even if the object has no custom delta properties. ...

Dormancy validation log warnings when COND_Never property changes

FRepLayout::DiffProperties doesn't check if the property's conditions is COND_Never or if the Parent Cmd's flags have the ERepParentFlags::IsLifetime flag (which FRepLayout::InitFromClass doesn't se ...

Cooker Generated Packages: Actors can trigger the "load" of generated packages from linker load and load them incorrectly

Generated packages have to be constructed by the cooker via FGeneratorPackage::CreateGeneratedUPackage. Some fields on the UPackage are set and ICookPackageSplitter->PopulateGeneratedPackage is call ...

Path Tracing shadow artifacts

First picture lit is used [Image Removed] Second picture PT is used, this occurs under certain angles of incidence. [Image Removed] ...

Volume artifacts (Bleeding)

Visual Noise on Thin Translucent materials with a Directional Light

Regression in testing This occurs with hardware and software ray tracing, as well as moveable and static lights This occurs regardless of anti aliasing. This was tested with DX12 ...