FJsonObjectConverter::ExportCallback_WriteISO8601Dates allows for writing FDateTime that does not have ticks

UE - CoreTech - Mar 12, 2025

Context: `FJsonObjectConverter` is a built-in UE class that makes it easy to convert JSON objects to and from UStructs, including `FDateTime`, which implements a date and time. Problem: An uniniti ...

Incorrect derivative ops detection when Add node is used with Nanite Pass Switch node in material graph

UE - Rendering - Graphics Features - Mar 11, 2025

Plugging an Add node which adds a constant value into a Nanite Pass switch node results in derivative ops to be detected where there should be none (which show up as red in the No Derivative Ops deb ...

When painting on a landscape with edit layers, there are UV distortions happening across the boundaries of paint layers when material is using SetMaterialAttributes

UE - Graphics Tools - Terrain - Landscape - Mar 10, 2025

Context Landscape Edit Layers enables users to paint landscapes using non-destructive layers, and can add multiple layers to the landscape that can be edited independently from each other. Problem ...

AssetRegistry has poor performance when a large map is resaved: Directory IO

UE - Foundation - Data Pipeline - Cooker - Mar 10, 2025

IO cost of directory scans is one of the costs present in the AssetRegistry when a large map is resaved. Maps can have external actors which all have to be rescanned and reported to the map for incl ...

Resetting material instance parameters to default value does not update the appearance of the object that the material is applied to

UE - Rendering - Architecture - Materials - Mar 10, 2025

When a material instance with exposed parameters is applied to a landscape; the parameters set to a new value and then reset to back the default value, the landscape does not respect the new default ...

Invalid DumpGPU capture when ProjectDisplayedTitle contains special utf8 chars

UE - Graphics Features - Mar 7, 2025

Placing a special UTF-8 character into the "ProjectDisplayedTitle" will result in GPU dumps failing to open. This appears to be because the dump will switch between us-ascii and UTF-16 file formats ...

Add support for motion data on SteamDeck (Steam Controller plugin)

UE - Gameplay - Input - Mar 7, 2025

We have a UDN user with a proposed change: https://udn.unrealengine.com/s/question/0D5QP00000yo70w0AA/add-support-for-gyro-motion-data-to-steam-controller-plugin?fromCase=1 Hi, we were adding gyr ...

RootMotionModifier_SkewWarp bug

UE - Anim - Gameplay - Mar 6, 2025

In /Game/ABPLinkingShowcase/Blueprints/Pawn_ABPLinkingCharacter: The character mesh’s root location is lower than the capsule’s lowest point. This is what causes the issue. Based on the event graph, ...

Crash trying to convert skeletal mesh to Nanite

UE - Rendering - Graphics Features - Nanite - Mar 6, 2025

In SkeletalRenderNanite.cpp / FDynamicSkelMeshObjectDataNanite::UpdateBonesRemovedByLOD, bone indices are of type FBoneIndexType (defined as uint16 from BoneIndices.h), instead of int32. On line 18 ...