Unreal Engine Issues

OnlyTickMontagesAndRefreshBonesWhenPlayingMontages visibility option updates anim instance multiple times

The OnlyTickMontagesAndRefreshBonesWhenPlayingMontages setting added in 5.4 is broken.  It only works because it unintentionally forces a second call to UAnimInstance::UpdateAnimation (via RefreshBo ...

Masked TwoSided material causing lumen direct lighting to leak through walls

It appears that LumenScene's Hardware Ray Tracing is causing light leaking into a sealed room (which should be perfectly black). This bug does not appear to happen on AMD GPUs. ...

City Sample vehicle does not always produce an EndOverlap Event

Reported on UDN: Something in the setup of the City Sample vehicles means that if a vehicle starts inside a  Box Collider Component then it won't generate an EndOverlap when exiting. Vehicles in ge ...

Creating MaterialInstanceDynamic for a moving/crumbled geometry collection component, the rendering position is reset to the initial location

Creating a MID makes the render state dirty and the engine will recreate a new scene proxy without the current attitude. This results in rendering the object in incorrect location. Here is a tempor ...

Reloading string table assets breaks references to strings and logs warnings

When using the "Reload" asset action on a String Table asset, any Text variables that reference the string table would break and say "<MISSING STRING TABLE ENTRY>". ...

PhysicsControl-enabled controls occasionally teleport to origin

Occasionally, PhysicsControl controls will teleport to the world origin. This is sporadic and generally fixes itself either with a restart. In the licensee's case, the controls were also animation d ...

Using "Change Class" on Spawnables, Possessable references retain old Class info

Changing Class for Spawnable objects in Level Sequence did not have any impact on Possesable objects in Subsequence. It's still referencing the previous Class. Also found in Release-5.4, CL: 329753 ...

[CAD Import] Metadata are totally different when loading an IFC file through TechSoft.

Landscape is missing its material when running a packaged project on Linux arm 64

From licensee: The project contains a small flat terrain with a basic material attached to it - just a single texture sampler connected to the base color output. Also in the project is a skeletal m ...

Unable to Create New Niagara User Parameter After Deletion without Niagara Editor Window Restart

When a user deletes a Niagara User Parameter within the Niagara System editor window, attempting to create a new parameter with the same name immediately after deletion results in an error. Despite ...