Crash when rendering cinematic in a Separate Process without "-NoLoadingScreen" cmd argument

UE - Anim - Sequencer - Jul 5, 2016

Crash when rendering cinematic in a Separate Process without "-NoLoadingScreen" cmd argument. Occurs in 4.12 and 4.13 in both Matinee and Sequencer Error message: Assertion failed: SizeX > 0 && S ...

Rarely, unmodified Niagara will cause diffs and bloat the patch.

UE - Niagara - May 3, 2022

Attached is a project that picks up Niagara from the content sample. The probability of reproduction is about 1/10. The simpler the project, the lower the reproduction probability. I am attaching ...

FBX export from UE4 with multiple materials the UV is corrupted

Tools - Apr 18, 2016

When exporting a Static Mesh from within UE4 that has multiple materials, some of the material IDs will be condensed into a single ID which will mess up how the material assignment for that part of ...

Crash when using Mesh Reduction on ScotsPine_01 for LOD3

UE - Graphics Features - Jan 30, 2017

A crash occurs when trying to use the Mesh Reduction tool for the ScotsPine_01 static mesh from the Open World Demo collection. The assets from this project are usually very processor heavy due to ...

Importing FBX creates new materials when using the search materials import setting

UE - Editor - Content Pipeline - Import and Export - Nov 1, 2017

There is an issue when importing FBX that creates new materials when using the search materials import setting. Instead of being able to use the material that is in the Base Material name, the textu ...

The "Random Integer in Range from Stream" returns the same value if the seed is power of 2 of anything above 22.

UE - Foundation - Core - Aug 7, 2019

When using the "Random Integer in Range from Stream" where the seed is a power of 2 after a certain point (2^22) the random integer that is returned is the always the same. If the seed is 2^23 + 1 i ...

When very far out from the map origin, large static mesh is not streaming in until player is close in world partition even though it's within loading range.

UE - World Creation - Worldbuilding Tools - World Partition - May 7, 2025

Context World Partition has a distance-based level streaming system that provides a complete solution for large world management. Problem The problem is that when the player and large static mesh a ...

Costs of Static Lights on Render Thread

UE - Graphics Features - Jun 9, 2016

A Japanese developer's making a scene that has over 4000 static point lights. They thought the lights don't affect rendering in runtime. But they realized the RenderThread's costs become bigger. I ...

Enabling Shader compilation via XGE for 4.18 Editor downloaded from Launcher doesn't work, prevents shaders from compiling at all, editor from loading in some cases

UE - Foundation - Build - Rocket (Installed Engine) - Nov 9, 2017

If you enable Shader compilation via XGE by setting r.XGEShaderCompile = 1 in ConsoleVariables.ini in 4.18 Editor downloaded from Launcher, it prevents shaders from compiling at all, and as a result ...

[CrashReport] Access violation in UE4Editor_Engine!TOctree<TVolumeLightingSample<3>

UE - Graphics Features - Jun 14, 2017

This is a common crash in the 4.16 release. The callstack for the issue is essentially the same as [Link Removed], however that issue had confirmed repro steps and was verified fixed for 4.16.0. A ...