UV Flipping Mode Causes Stretching of Particles

UE - Niagara - Nov 17, 2017

If "UVFlipping Mode" under Rendering on the Required node of an emitter is set to anything other than "None," the particles can become stretched and distorted. As a workaround, I have discovered th ...

Crash When Assigning a Static Mesh to the "Sample Static Mesh" Module

UE - Niagara - Jun 28, 2018

When assigning a static mesh to the "Sample Static Mesh" module, the engine will crash as soon as you select a mesh and click "Fix Now". If the mesh already has CPU access enabled it will crash as s ...

Edits of node properties that are not stored on pins do not diff correctly

UE - Gameplay - Blueprint Editor - Oct 2, 2015

Currently details changes to the following are not noticed by the Diff tool when diffing AnimBPs:State Machines (i.e. Max transitions per frame)Transition rulesConduitsStates This also affects non- ...

"Combine Meshes" Breaks Material Slot Assignment

Tools - Jan 18, 2017

When importing an FBX with several different meshes and multiple materials with "Combine Meshes" enabled the materials will get assigned to incorrect portions of the mesh. I've included a version o ...

Landscape Layer Blend generates bad code for preview shader

UE - LD & Modeling - Terrain - Landscape - Sep 23, 2019

It breaks only when compiling the preview shader. Adding a preview weight to the Layer0 on the Layer Blend node fixes the problem. The source of the bug is in UMaterialExpressionLandscapeLayerBlend ...

Crash when entering Path Tracing view mode if r.Decal.NormalReprojectionEnabled true

UE - Graphics Features - Path Tracer - May 16, 2025

Cash when entering Path Tracing view mode if r.Decal.NormalReprojectionEnabled true The licensee has reported: This crash happens because the DeferredShadingRenderer tries to extract the normal GBu ...

DataTable::LoadStructData allocating wrong size

UE - Foundation - Core - Oct 5, 2016

Pointed out by a licensee here: UDataTableを読みこんだ際のメモリ破壊について When reading the `UDataTable, in DataTable::LoadStructData()` the contents of the struct are interpreted[Image Removed], but the size of ...

TVOS - Packaging CPP project fails when "Support Bitcode in Shipping" enabled

UE - Platform - Mobile - Dec 13, 2018

Unable to package a CPP project with Bitcode enabled Confirmed in MAIN 4.22 @ CL 4655014 with error [404/405] sh /Users/compile/UE4/Builds/RDU-WD-11740/D/Projects/AJ_421CPP_4.22/Binaries/TVOS/ ...

Printing a string or character to the device output log does not display the string/character

UE - Platform - Mobile - Aug 30, 2019

If you point to a character or text data type and log it into the Device output log, the variable will not appear in the output. However, any other data type will appear. ( float, int, etc.). Found ...

UDN : Mutable Trying to Access Invalid UEdGraph Pointer

UE - Anim - Mutable - Mar 6, 2025

Hello, We've started seeing a crash within Mutable when it tries to access the source graph in PIE. This only seems to be a problem when running a dedicated server as a separate process. We integra ...