GPU Particle Collision causes shaking when set to bounce with low resilience.

UE - Niagara - Jul 27, 2016

A particle emitter with GPU sprites on certain settings will shake violently as they collide with the ground. This requires there to be a strong Const Acceleration module and Collision with low resi ...

BP - Editing defaults on a nested subobject of a component inherited from a native parent class won't preserve those defaults when the BP is instanced.

UE - Gameplay - Components - Jan 19, 2017

I think the issue is that in GetInstancedSubobject() (CoreNative.cpp), the following bit of code is not considering that the instanced subobject might be outered to another instanced subobject withi ...

Editor crash when using Animation BP pose watch

OLD - Anim - Apr 7, 2020

We encountered a crash when using Anim BP Pose Watches to inspect poses on actors in a PIE instance. Specifically it seems ending the PIE session while the Anim BP is still watching the actor in the ...

Get Constraint Force node always returns a magnitude zero vector

UE - Simulation - Physics - Solver - May 4, 2022

Get Constraint Force node always returns a magnitude zero vector. Repro Rate: 3/3 Tested this in //UE4/Release-4.27 @ CL#18319896 and was able to get the constraint force, it is a regression. ...

In a listen server, when a client moves, anim notifies don't get fired for the server/host.

UE - Anim - Gameplay - Nov 14, 2022

Reproduced 3/3 times. Was not able to reproduce in //UE5/Release-5.0 - CL 20979098 Binary. Confirmed Regression. ...

YCoCg to sRGB?

UE - Niagara - Rendering - Mar 20, 2024

Both the material and the Niagara compute shader use the same function to interpret the YCoCg color data, but the Niagara compute shader returns an incorrect color. Also found on CL: 32347737 in Re ...

CreateD3D12Texture causes the Low Level Memory system to register two allocations for the same pointer on the same track channel

UE - Rendering Architecture - RHI - Oct 31, 2024

CreateD3D12Texture causes two OnLowLevelAllocs in LLM to be called with the same pointer and the same channel, leading to a warning. LLM WARNING: Replacing allocation in tracking map. Alloc/Free Mi ...

Editor crashes when using PCG SpawnActor with a DataLayer inside a Level Instance

UE - World Creation - Procedural Tools - Jun 4, 2025

A PCG actor is assigned to a DataLayer and placed inside a Level Instance. Then that Level Instance is placed into a World Partition map. When the SpawnActor node in the PCG graph is set to MergePCG ...