A chaos vehicle that moves at very high speeds with CCD enabled on the vehicle sometimes has a collision response that is abnormal where the vehicle loses a significant amount of speed when colliding with dynamic objects configured as One Way Interaction

UE - Runtime - Character - Dec 16, 2025

Context: Continuous Collision Detection (CCD) is being used on a Chaos Vehicle to avoid tunneling issues with certain surfaces as it prevents any missed collisions between fast moving particles and ...

Culling Distances Not Working For Static Mesh in Procedural Content Generation Tool and Foliage Tool

UE - Graphics Tools - PCG - Procedural Tools - Mar 28, 2025

When creating Foliage or Procedurally Generated Content the culling settings of the Static Meshes do not apply correctly. As soon as either a minimum or maximum cull distance is set the Static Meshe ...

In editor, sub level instance's streaming state persists incorrectly after toggling Level Behavior without saving

UE - Engine Scaling - Streaming - Level Instances - Jun 11, 2025

When adding a sub level with world partition streaming to a main level where the streaming is also enabled, setting* Level Behavior* of the sub level to Standalone, and saving the result, in the fir ...

iOS Shipping Build using std::thread crashes on launch

UE - Platform - Mobile - Jun 2, 2017

A user is reporting that using the following code in a GameMode class causes shipping iOS packages to crash on launch:void ANOGSSDKGameModeBase::StartPlay() { std::thread([](){ std::clog << "THRE ...

AddComponent node fails to be scheduled after adding an "expose on spawn" variable to an ActorComponent-based Blueprint Class.

UE - Gameplay - Blueprint - Nov 13, 2015

If an existing AddComponent node is placed in an Actor Blueprint's Event Graph for a custom ActorComponent-based Blueprint Class, the node will fail to be scheduled after adding a variable marked "E ...

UGameplayStatics::SpawnEmitterAttached keeps relative location when SnapToTarget is used.

UE - Gameplay - Aug 10, 2016

UGameplayStatics::SpawnEmitterAttached will keep relative position when using SnapToTarget. ...

Create Session does not work in a packaged game from any project that has used C++

UE - Networking - Dec 28, 2015

After adding C++ to a content-only project, Create Session no longer works in a packaged game. The following warning appears in the log: LogScript:Warning: CreateSession - Invalid or uninitialized ...

Compilation error when using Particle SubUV in Niagara Mesh Particles with Raytracing enabled.

UE - Rendering - Architecture - Niagara - Oct 12, 2021

The licensee has shared the following workaround for modifying NiagaraMeshVertexFactory.ush. struct FVertexFactoryInterpolantsVSToPS { TANGENTTOWORLD_INTERPOLATOR_BLOCK #if USE_PARTICLE_SUBU ...

Framerate drops when using SceneCaptureComponents with a RenderTarget in VR

UE - Platform - XR - May 14, 2018

Using SceneCapture in packaged VR projects causes poor performance. Also observed with SceneCaptureCube Does not occur in 4.18 ...