Unreal Engine Issues

Can't set "r.Shaders.Optimize" to false in UE5.4

The CVar "r.Shaders.Optimize" cannot be set to false from DefaultEngine.ini in the section "[ShaderCompiler]" as its help text describes. Also tested on UE5-Main, CL: 34200103 ...

Problem with material layers using interpolator nodes

The Vertex Interpolator Material Expression appears to collapse separate instances from separate Material Layers, leading to visual artifacts when used. Also tested on UE5_Main, CL: 34200103 ...

ControlRig & Sequencer: FindControlRigs returns rigs even if their track have been removed

Constraint Actor to Rig with Editor Utility Widget is working for the first time adding to the Sequencer. However if it was deleted and added to Sequencer again, run Scripted Actor Action shows Err ...

Case Child Actor Component validation error when set as editor-only

When a blueprint actor with a child actor component is placed in a level, and the child actor component is set as editor-only, the output log will show a validation error when the actor is moved and ...

SpringArmComponent with "Use Camera Lag Substepping" does not handle fluctuating frame rates correctly

The description of SpringArmComponent's "Use Camera Lag Substepping" option says "sub-step camera damping so that it handles fluctuating frame rates well". However, as noted and explained by a licen ...

Post Process Material Chain Graph does not work with the mobile renderer

Crash when exiting editor before EditorUtilityTask completes

If exiting the editor before the EditorUtilityTask completes, it crashes. It will not crash if canceling the UtilityTask and then exit the editor. The following implementation does not allow destruc ...

UClass::SparseClassDataStruct null at editor-time for child blueprints until compile

Child blueprints of a blueprint of a native actor class with sparse data can have an incorrectly null SparseClassDataStruct value, and thus fail to initialzie their SparseClassData. This affects edi ...

Async Physics incorrectly interpolates when multiple physics ticks pass

If a user set the transform of a Body from the game thread and physics is running multiple async ticks perf game tick, the transforms might be being calculated incorrectly. ...

Translucent materials with Modulate blend mode disappear with down-res translucency enabled

Reported from this UDN: https://udn.unrealengine.com/s/question/0D5QP00000MLlco0AD/active-dtr-doesnt-render-beforedofmodulated-materials?fromCase=1 The problem is that, except in very specific circ ...