Unreal Engine Issues

Actor blueprint 'bOptimizeBPComponentData' breaks subobject instantiation for runtime spawned actors in cooked builds

A user has reported that when an actor blueprint enables Generate Optimized Component Blueprint Data, default instanced objects of components are not properly duplicated in cooked builds. This resul ...

Message to rebuild lights does not display after static mesh position has changed

In a static lighting environment, moving static objects no longer marks the built lighting as invalid. This prevents the on-screen warning from appearing. Regression introduced in CL: 25964466 on / ...

Material Layering sometimes increses Shader complexity significently

Nanite meshes are lit differently in Actor Colorization view modes than non-Nanite meshes

When the Lit > Actor Coloration > Affects Navmesh or other Actor Coloration mode is used, Nanite meshes apply lighting differently than non-Nanite meshes which can make it difficult to use the Actor ...

Material instance UI doesn't show correct parameter preview for logic in a material function

The Material Instance UI doesn't show the correct parameter values when the logic is moved from the material graph into a material function used in that material graph. Example setup showing the wr ...

BlendListByEnum assumes that enum values are sequential

FAnimNode_BlendListByEnum assumes that values within a custom enum type are sequential (ie. the index 0 = value 0, index 1 = value 1).  But this is not true of all custom enum types, for example: U ...

Ortho near plane clips geometry in Editor Top view

When the viewport is in Top (ortho) Lit mode the near plane clips through geometry as you zoom the view in and out. ...

Incorrect Lighting With Exponential Height Fog And Light Function Atlas

There currently is a mismatch occurring when light function atlases are used in conjunction with exponential height fog. When the flag r.VolumetricFog.UsesLightFunctionAtlas is enabled, light shafts ...