Using GENERATED_BODY() instead of GENERATED_UINTERFACE_BODY() in an Interface code class results in a UHT crash when trying to build the project.

UE - Foundation - Core - Mar 3, 2015

Replacing GENERATED_UINTERFACE_BODY() with GENERATED_BODY() in 4.7.0 or above results in an Unreal Header Tool crash and build failure in Visual Studio. This was working in 4.6.1, but when tested i ...

Content Examples: Blueprints_Overview Stand 1.7 Spark particle system does not fire from coin

Docs - Samples - Jan 19, 2017

During runtime, the red coin in Stand 1.7 on the Blueprints_Overview map of Content Examples should emit a large spark particle system 5 times. While investigating, I tried disabling "Use Fixed Rel ...

Map load stalls in texture streaming code

UE - Graphics Features - Jun 13, 2017

A change was made to AActor.GetComponents which appends the results instead of resetting the output array. This seems to only impact 2 places in the code, and has a big side effect in the texture st ...

Unimplemented Simplygon function causes empty mesh LODs and crashes

Tools - Aug 31, 2018

When we do the refactor for MeshDescription we miss the staticmesh reduction project settings option and change only the quadric reduction. There are two possible fixes for this issue: 1. Implemen ...

Mobile VR - Render Targets not working with Mobile Multi-View

UE - Platform - XR - Jun 6, 2019

Render target materials display as black on mobile VR when Mobile Multi-View is enabled. Also confirmed with LDR capture source. User also reports issues with scene depth (potentially fixed with [ ...

Crash when editing FRuntimeFloatCurve's curve from sequencer's edit key window

UE - Anim - Sequencer - Mar 31, 2023

Crash when editing a FRuntimeFloatCurve curve exposed through EventTrack or a self-made Struct from the sequencer key edit window. FRuntimeFloatCurve does not support Expose to Cinematic, so this m ...

Blend Stack node doesn't have a valid FDeltaTimeRecord

UE - Anim - Runtime - Apr 19, 2024

The blend stack node doesn't generate any values for its DeltaTimeRecord.  This can be tested with the fix for [Link Removed] shelved at 32747789.  Since there isn't a tick record directly associate ...

Add Substrate Material Support to Lumen Performance Overview

UE - Graphics Features - Substrate - Feb 10, 2025

There is a discrepancy when inspecting Substrate materials in the Lumen Performance Overview. Compared to viewing non-Substrate materials the overview show all surfaces in red indicating that Lumen ...

GPU Particle Collision changes based on Normal Intensity on Colliding Surface

UE - Graphics Features - Jun 18, 2015

Increasing the intensity of a Normal Texture on a colliding surface will cause the collision of GPU particles to behave strangely, looks to be falling through floor, when you are using a Constant Ac ...

Cannot move instances of a hierarchical static mesh component in the blueprint editor viewport

UE - Gameplay - Components - Apr 12, 2016

Can move individual mesh instances of a regular instanced mesh component in the blueprint editor, but not hierarchical ones. Originally reported as a pull request in [Link Removed], but we rejected ...