Unreal Engine Issues
Unreal Engine Issues
[Groom] Very thin hair has incorrect raytraced shadow on edges
UE - Graphics Features - Lumen - Jun 8, 2020This only happens when 1) Hair Width is very small. e.g. 0.01 in the example 2) Light has raytraced shadow and Samples Per Pixel has a value > 1. e.g. 8 in the example The problem seems to be rel ...
Anim Notify States are ended when CustomTimeDilation is set to zero
UE - Anim - Runtime - Oct 12, 2022UDN link: https://udn.unrealengine.com/s/question/0D54z00008BEDfJCAX/set-actor-time-dilation-to-0-during-a-animation-notify-state-cancel-it?fromCase=1 Notify gathering functions (e.g. UAnimSequence ...
Shader Model 5 and Tessellation causes unintended effects on Linux
UE - Platform - Linux - Jul 6, 2016Using Shader Model 5 and tessellation on Linux gives strange results that are not present when used on Windows ex: 1) When using Shader Model 5 on Linux, turning on Translucent blend mode and Tesse ...
Local Variable loses value after reference moves file location
UE - Gameplay - Blueprint - May 23, 2017Local Variable loses value after reference moves file locations. This does not just affect construction scripts, following these steps with a function instead produced the same result. This issue do ...
[AI] Compilation error when using const version of FNavigationPath::CastPath<PathClass>() const
UE - AI - Navigation - Jan 5, 2022Const version of function is not used elsewhere in the engine so it usually gets skipped when compiling. Produces the following error when compiling: UnrealEngine\Engine\Source\Runtime\Navigation ...
The crash reporter tool does not start on Windows 8.1 machines when running the Engine built from source code.
UE - Foundation - Core - Dec 5, 2014The source code to build the Engine that is available from GitHub includes the file dbghelp.dll, which prevents the crash reporter tool from starting on Windows 8.1 machines. This file is not presen ...
Migrating assets to a plugin causes references to break
UE - Editor - Content Pipeline - Content Browser - Jun 14, 2018The migrate function is meant for moving assets from one content folder to another, so it does no actual modification of the references in the migrated assets. This is normally fine, since we expect ...
Landscape components not returning physical material with LineTrace in Editor mode
UE - Simulation - Physics - Query - Sep 13, 2023The OutHit from a LineTraceByChannel against a landscape in Editor is not returning the Physical Material of that landscape. While PIE there is no issue. While using BoxTrace (even in Editor) there ...
Engine no longer compiles after backporting RHI thread improvements and crash fix
UE - Rendering - Architecture - RHI - Apr 24, 2025Unreal Engine 5.4 code will no longer compile after applying both the RHI improvement code changes as described in [Link Removed] and the fix for the crash described in [Link Removed]. The compilati ...
Control Rig Creation Crash Triggered by “skel” Prefix in Skeletal Mesh Name
UE - Anim - Rigging - Control Rig - Nov 27, 2025When generating a Control Rig from a Skeletal Mesh that contains “skel” in its name—or uses it as a prefix (i.e. skel_test)—Unreal Engine crashes. The crash occurs both when using the native Creat ...