Unreal Engine Issues

Custom Primitive Data color widget not applying correctly to static mesh components in Blueprint editor.

Context Custom Primitive Data is used to store custom data in an index array that is accessible through Blueprint and code. This allows for variations across instances of the same mesh without needi ...

Temporal blur artifacts on Geometry Cache Components in Blueprint actor

When a Geometry Collection is in a Blueprint, attached to other components, it can render incorrect motion vectors at some angles. In the test project, any angle that is not a multiple of 45 will re ...

GetAllocatedSize returns inaccurate number of bytes

When calling GetAllocatedSize() on a TBitArray it will round down the result of MaxBits / NumBitsPerDWORD. This means that not enough bytes are allocated when the MaxBits is not divisible by NumBi ...

Groom Hair Visual Issue with RBF Interpolation Enabled

When "RBF Interpolation" is enabled in the Groom settings, applying an Animation Sequence to a Skeletal Mesh that animates at a position far from the world origin causes the bound Groom shape to bec ...

Scene Capture 2D will default back to View 0

The scene capture will revert back to the Character BP that is placed in the level when player 2 is not moving. When they are moving the scene captuer will show correctly. You can get around this ...

Default value propagation of instance subobjects doesn't work consistently

EnumRedirections from a Blueprint enum to a c++ enum does not redirect everything correctly.

There is an engine bug when using the EnumRedirects feature inside a config file. If we have a Blueprint Enum used in our blueprints, and we want to convert all the Blueprint enum references to a C+ ...

Physics constraint component doesn't work when placed inside a child actor, while using world partition and streaming is enabled

Context: In a World partition level, to reduce complexity and provide a scalable solution when creating new projects, grid cell streaming can be enabled. Problem: The problem is that physics constr ...

Hardware Lumen Surface Cache Artifacts on Nanite Geometry

When using Hardware Lumen with Nanite-enabled meshes in UE 5.6+, black / dark surface cache artifacts appear that result in generally darker and unstable lighting. These artifacts are not immediatel ...

Chaos sometimes can not generate contact points while two dynamic convex hulls actually collide. It results in instability in the contact behavior​ - such as jittering, inconsistent contact forces, or unexpected collision responses.

Context: Chaos Physics is able to use convex hulls to represent object collision geometry for queries and simulation. Problem: Chaos sometimes can not generate contact points while two dynamic conv ...