Instanced Static Meshes ignore max World Position Offset Displacement for bounds after UpdateInstanceTransform is called

UE - Rendering - Graphics Features - Jun 18, 2025

When an Instanced Static Mesh Component (ISMC) uses a material with a non-zero Max World Position Offset Displacement, the bounds are correctly expanded at initialization. However, after calling Upd ...

LayeredBlendPerBone without BlendRootMotionBasedOnRootBone exaggerates root motion

UE - Anim - Runtime - May 27, 2023

When BlendRootMotionBasedOnRootBone is false, the LayeredBlendPerBone is aggregating root motion of the child poses ontop of the base pose root motion.  (ie. if the first child pose's blend weight i ...

USceneComponent::PropagateTransformUpdate could avoid calls to MarkRenderTransformDirty when transform does not change

UE - Gameplay - Nov 16, 2016

From the UDN: "In USceneComponent::PropagateTransformUpdate, even when Transform has not changed, Bounds are updated and MarkRenderTransformDirty is called. I think that judging whether Bounds have ...

The SetEmitterEnable BP function needs implementation

UE - Niagara - Mar 2, 2020

The BP function calls FNiagaraSystemInstance::SetEmitterEnable, which sets ExecutionState on the emitter instance to ENiagaraExecutionState::Inactive. FNiagaraSystemSimulation::PrepareForSystemSimul ...

Crash loading sublevel that had name changed when it is unloaded.

Tools - Apr 2, 2019

Updated name of sublevel leads to crash when it is about to be loaded. ...

Last frame pose is not evaluated when playing Anim Montage with Blend Out Time of 0 in AnimNodeSlot

UE - Anim - Gameplay - Apr 26, 2022

When playing AnimMontage with BlendOutTime set to 0.f with AnimNode_Slot of AnimBP, it seems that the last frame pose may not be evaluated. this issue does not occur in high frame rate and does not ...

SceneCapture2D Component Show Flags that are Modified in a Blueprint initially are Copied not Referenced

UE - Graphics Features - May 17, 2019

If you disable show flags in a SceneCapture2D component of a Blueprint, trying to re-enable them in the Blueprint will not update instances in a level. Anything that was left alone will change along ...

Lumen appears to ignore custom World Origin Location

UE - Graphics Features - Lumen - Jul 12, 2022

Lumen doesn't update when the World Origin Location is changed. ...

Cannot move movable components of actors if using drag if PIE or Simulate

UE - Editor - Workflow Systems - Mar 3, 2021

If the actor is in sublevel and user play simulate or PIE, the actor can't be moved by drag gizmo. Even if under the same conditions, editing transform of detail panel work properly. So I guess that ...

Spring Arm rotation only prints Yaw after 4.17 conversion

UE - Gameplay - Aug 11, 2017

Spring Arm rotation only prints Yaw after 4.17 conversion. In 4.16 it would print the Yaw, Pitch, and Rotation as expected. The spring arm by itself prints the rotation correctly but once a camera ...