Unreal Engine Issues

Performance slowdown when ray tracing is disabled due to SetResidencyPriority

When a game is compiled with ray tracing disabled (D3D12_RHI_RAYTRACING=0) and the GPU the game is running on becomes low on VRAM, frame time is negatively impacted and doesn't recover. The D3D12_RH ...

Enabling Substrate causes MaterialGraph node previews to render black

Node previews in MaterialGraph with Substrate enabled render solid black in 5.6. The latest 5.5 engine does render previews correct with substrate enabled. ...

Mover standalone backend allows non-persistent sync structs to carry over between frames

Only certain sync state structs are intended to persist between frames. These are configured via MoverComponent's PersistentSyncStateDataTypes array. There appears to be a bug in the way the standa ...

Niagara Regression - Looping particle with Spawn Burst Instantaneous on time 0.0 flickers for a frame between loops

Note: This worked correctly up to UE 5.4, but repros from UE 5.5 up to mainline latest. If a Niagara Emitter is set up with "Spawn Burst Instantaneous" on time 0.0, and the spawned particle(s) have ...

Adding vertex color to a model that has morph targets, removes or invalidates the morph targets.

[AI] Automatically generated navlinks do not contain the poly flag for being a navlink.

Automatically generated navlinks are failing to be detected by FNavMeshNodeFlags::IsNavLink. The area flag assigned to the navlink end points is not including the NavLinkFlag. ...

Offset Root Bone Node needs reconstruction from velocities

The experimental Offset Root Bone node does not respect velocities, meaning that it does not work when a character is based on a moving platform. The capsule will rotate with the platform, but the r ...

Bake Pose is not applied correctly when using LODSettings asset

The Bake Pose setting does not work when using a SkeletalMesh LODSettings asset. After the change in CL22878911, the BasePose in the LODSettings asset is no longer copied to the BakePose in the skel ...

URuntimeVirtualTextureComponent::RequestPreload not working for some edge cases

A licensee has reached out to us to inform us that the logic for preloading at times fails to account for adaptive virtual textures when the requested mip level is not in the shared AllocatedVirtual ...

Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...