Editor crashes when importing 4.5.1 project to 4.6

UE - Gameplay - Blueprint - Dec 9, 2014

The user converted a copy of their 4.5.1 project to 4.6. Upon opening that project, the editor crashes. Deleting certain widgets allows the user to open the project, but opening any map results in a ...

Bad references for Lighting Scenarios when moving Levels and Map Build Data Registry to different Folder

Tools - Feb 2, 2017

When moving Lighting Scenario Levels and their associated Map Build Data Registry to a new folder within the Content Browser, the references within the Levels tab are updated as [MapName_BuiltData]. ...

Subsurface Profile Materials That Are Illuminated By Particle Lights Render White

UE - Graphics Features - Feb 9, 2017

Due to the changes made to subsurface profile (implementation of full resolution skin shading) it now renders white or with heavily faded base colors under certain conditions. In this case it is wh ...

Crash when element is added to a map variable with unhashable key

UE - Gameplay - Mar 21, 2017

Crash when element is added to a map variable with unhashable key. An error is thrown on compile but an element can still be added under the Details panel of the variable. Crash Reporter: [Link Rem ...

Hierarchical and normal Instanced Static Mesh Components do not maintain PerInstanceRandom values when transforms are modified

UE - Graphics Features - Nov 6, 2017

When using PerInstanceRandom in a material that is applied to a Hierarchical or normal Instanced Static Mesh component, there are issues of the value resetting when certain transform operations are ...

Bug - Animations and Keep State Fail when scrubbing backward.

UE - Anim - Sequencer - Jan 30, 2020

If you scrub past an animation with keep state, and scrub into an animation with defaults everything is fine. When you scrub back to the animation with keep state, the animation breaks, until there ...

Color space transform in the UI composition is incorrect on DX12 HDR (r.HDR.UI.CompositeMode=1)

UE - Graphics Features - Jun 11, 2021

Color space conversion in the UI composition is incorrect on DX12 HDR. In the main() function In CompositeUIPixelShader.usf, you can see the following color space transform.// sRGB -> RRT -> ODT ...

Material slot assignment incorrect after mesh reduction completely removes all triangles from a section

UE - Editor - Content Pipeline - Asset Build - Apr 28, 2022

When mesh reduction results in a section becoming empty, the material slots are incorrectly assigned. e.g. if section 0 gets removed due to it having no triangles after reduction, then its material ...

Deferring Blueprint CDO construction at load time is leading to some data loss.

UE - Gameplay - Blueprint - Jan 27, 2023

Various licensees are reporting data loss on load due to the change that was made for [Link Removed] in which we now defer Blueprint CDO construction on load until the finalization phase. This issu ...

[CrashReport][Assert] UnrealEditor-RHI!FRHIResource::MarkForDelete() [Engine/Source/Runtime/RHI/Private/RHIResources.cpp:49]

UE - Rendering Architecture - Materials - Dec 18, 2024

One of the users described this issue as below. "At seemingly random times while working in the material graph, some action will cause a hitch or freeze, and quickly after the engine will crash, an ...