Popping Ribbon UVs

UE - Niagara - Mar 10, 2025

Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...

Level Blueprint zoom value is different for different templates.

Docs - Samples - Jan 30, 2017

I'm not sure where to set this value, but it's extremely noticeable when the value defaults to -7 and you go and place a node and it looks like a colorful square smaller than your fingernail. I tri ...

InstancedStaticMesh instances fail to render on a mobile device

UE - Graphics Features - Nov 13, 2014

When a project with an InstancedStaticMesh is used in a level, the static mesh is failing to render on a mobile device Tested on a nexus 5 and an iPad air OS 8.1 ...

Bitfield Bools in a struct and AnimBlueprint transitions not working together

UE - Gameplay - Blueprint - Apr 12, 2016

USTRUCT(BlueprintType) struct FTestStruct { GENERATED_USTRUCT_BODY() UPROPERTY(BlueprintReadWrite) uint32 ValueC : 1 ; UPROPERTY(BlueprintReadWrite) uint32 ValueD : 1 ; }; A ...

[CrashReport] Linux crash - /usr/lib/x86_64-linux-gnu/dri/radeonsi_dri.so()

UE - Platform - Linux - Nov 16, 2017

This is a new Linux crash in 4.18.1. There are a few similar but different callstacks that reference dri/radeonsi_dri.so() I've attached a log, but none of the ones I've looked at appear to contai ...

Empty Mesh Sections with MergeActors Tool

UE - World Creation - Worldbuilding Tools - HLOD - Sep 27, 2019

Map Check will output the following error, which makes no sense: SM_FourCubes_1 - 1 element(s) with zero triangles in static mesh 'SM_FourCubes' ...

Command r.DebugSafeZone.Mode 0 does not disable overlays

Tools - Feb 19, 2020

Running the console command r.DebugSafeZone.Mode 0 does not disable all overlays.  The issue occurs when setting custom values in DefaultEngine.ini as well.  Tested using the following settings:  ...

Set Actor Enable Collision is not replicated

UE - Networking - Jul 14, 2015

Set Actor Enable Collision is not replicated. Reproduced in 4.7.6, 4.8.2, and Main (//depot/UE4/Promotable-CL-2619427) ...

TranslucentVolumeAmbient is darkened in InjectTranslucencyLightingVolume pass when using VSMs with r.Shadow.Virtual.ForceOnlyVirtualShadowMaps is Off

UE - Graphics Features - Shadows - Nov 18, 2024

CSM targets are still created and affect the InjectTranslucencyLightingVolume pass when moving in a project that only uses VSM causing over brightening of fog planes and other translucent meshes. r ...

World Position Offset Object Shadow Cast on Translucent Object Causes Flickering

UE - Graphics Features - Jan 21, 2025

When a WPO (World Position Offset) object casts a shadow on a translucent object, the translucent object flickers continuously as the shadow passes over it. Initially logged as a 5.5/5.5.1 but also ...