Unreal Engine Issues

Insufficient precision of Decode71 function

Encode71 and Decode71 in DeferredShadingCommon.ush are functions that convert 8-bit values ​​to 7-bit values ​​and mask values, and licensees have reported that the accuracy is insufficient when usi ...

Replicated subobjects list crashes with unreachable yet valid objects when UE_NET_SUBOBJECTLIST_WEAKPTR=0

This seems to occur when the subobject is considered unreachable but is not yet pending kill/marked as garbage. In this case, IsValid returns true while FWeakObjectPtr::Get returns nullptr for the o ...

ChaosWheeledVehicleMovementComponent is breaking the const CDO contract and changes to the instances are being applied to the CDO

As described by the licensee, the const CDO contract is being broken on ChaosWheeledVehicleMovementComponent. The issue the licensee is facing is that by spawning cars with different configurations, ...

WPO is incorrectly generated on materials using Material Attributes as input to Landscape Layer Blend node

This comes from this UDN : [Link Removed] It occurs with this setup :  [Image Removed] , where Set Material Attributes expressions act as inputs to the Landscape Layer Blend material expression. ...

Missing Triangles on scaled MetaHuman assets with Nanite enabled

Additional information: only happens when all three conditions are true: the camera is very close to the character, the MH is Nanite, and a scaled mocap animation is appliedmaterial is opaque, shows ...

Soft angular constraints solve velocity like hard constraints

Soft angular constraints are solving velocity like hard constraints. Instead of swinging back and forth, the affected body just snaps to 45 degrees. Check the steps to reproduce for more details. Th ...

[Mobile/Forward Rendering] PlanarReflection does not work when the reflection plane faces certain directions

Note: This repros on 4.27 and all 5.x versions. When using the mobile renderer and/or forward shading, Planar Reflection will simply not work if the reflection plane normal has components that add ...

Xcode 26/16.4 Metal Toolchain generates metallib's that are not compatible with iOS 16

Below is the error output from FirstPerson template as a C++ project: {+}../../../FirstPerson58CPP/Content/firstperson58cpp_sf_metal_es3_1_ios-metal_es3_1_ios.0.metallib, 5881486 bytes!2025-09-23 1 ...

Landscape Transparent with r.Lumen.DiffuseIndirect.Allow 0

Implied Decal Blend Modes don't properly account for Material Attributes usage

I've attached a project with the necessary materials that demonstrate this issue. I would expect that just because a Set Material Attributes node is inside a material graph it wouldn't affect the de ...