Crash in FNiagaraGPUInstanceCountManager::AddDrawIndirect when Android Vulkan Mobile preview platform is enabled

UE - Niagara - Nov 14, 2024

In the Android Vulkan Mobile preview mode, when multiple GPU niagara systems are visible and the user moves the camera around the level it can cause a crash, potentially caused by a race condition o ...

'prefix parameter names' checkbox in a material function's settings does nothing.

UE - Rendering Architecture - Materials - Nov 14, 2024

Prefix Parameter Names checkbox does not work as expected, and the Group names are unmodified. The value "UMaterialFunction::bPrefixParameterNames" does not appear to be used anywhere in the Engine ...

Direct Link is not finding source - macOS Sequoia

UE - Editor - Content Pipeline - Datasmith - Exporters - Nov 14, 2024

Direct link with macOS Sequoia seems to be broken as Twinmotion cannot detect the Direct Link source, it seems the data is properly written in the cache directory. ...

Validity of a workaround for an issue with MobileRenderer where RecieveShadow can't be rendered properly

UE - Platform - Mobile - Nov 11, 2024

Dynamic instancing is likely causing an issue where meshes that need shadows are getting combined with meshes that do not need shadows causing missing shadows. Tests were done with CSMs. Reproducti ...

When a Niagara System has SimTarget set to GPUCompute Sim, CameraQuery is only returning data from the Player0 camera, ignoring the PlayerControllerIndex.

When a Niagara System has SimTarget set to GPUCompute Sim, CameraQuery is only returning data from the Player0 camera, regardless of PlayerControllerIndex. The expected behavior would be to have the ...

ISM + WPO = broken motion vectors?

UE - Graphics Features - Nov 5, 2024

Instanced Static Meshes will have incorrect velocity if a Material uses World Position Offset. Fixed WPO in a material causes significant velocity on the ISM. This was also replicated in //UE5/Rele ...

Actors removed from the world are unregistered both before and after EndPlay

UE - World Creation - Worldbuilding Tools - Nov 5, 2024

Actors that are removed from the world have UnregisterAllComponents called twice. Removal can be caused by unloading a data layer that owns the actor. In cases like exiting the application or destr ...

Light Function and World Position in 5.4

UE - Graphics Features - Nov 4, 2024

When rendering a Light Function into the Translucency Lighting Volume, the World Position Material Expression returns the position relative to the Camera (unrotated), not the World. This can be mor ...

Navigation: Exiting game while async nav building tasks are running can cause null pointer access of OctreeController.NavOctree from worker thread

UE - AI - Navigation - Nov 1, 2024

Context Projects can turn on the project setting bDoFullyAsyncNavDataGathering to execute navigation mesh building tasks on worker threads. Some of these tasks will access the NavOctree, whose life ...

Null Material Layers in Material Instances cause Opacity Mask and WPO to break on Nanite Meshes

UE - Rendering Architecture - Materials - Oct 31, 2024

When a Material Instance is loaded that has a nullptr layer in StaticParametrs.Materiallayers.  The Material Instance will create it's own CachedExpressionData but the ConnectedParameterMask will be ...