ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced

UE - Rendering Architecture - Materials - Apr 16, 2024

ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced (e.g. RegisterIndex of the texture is [3] or [7]) because FMeshRenderer::RenderMaterialTexCoordScales() use ...

Passing array from blueprint to C++ causes performance drop

UE - Gameplay - Blueprint - Sep 8, 2015

Passing a blueprint array as an argument to a C++ function causes a spike in Frame rate, game and GPU. This spike is noticeable when using UnitGraph. Attached screenshots show difference in UnitGr ...

Blurry RVTs after camera jump

UE - Graphics Features - Aug 7, 2025

When using Runtime Virtual Textures (RVT) on landscape in UE 5.5+, nearby tiles may remain blurry (low-resolution mips) after launching PIE or making large camera jumps (e.g. via bookmarks or viewpo ...

MemReport does not seem to respect mesh streaming

UE - Rendering Architecture - Aug 6, 2024

The function "FStaticMeshLODResources::GetResourceSizeEx(...)" does not take into account that the buffers might be emptied, due to Mesh Streaming. This causes "obj list" to report sizes larger than ...

User Play Space Rot does not change anything in Client Play Camera Shake

UE - Gameplay - Jun 11, 2015

User does not change anything in Client Play Camera Shake. Reproduced in 4.8 and Main (//depot/UE4/Promotable-CL-2581498). This is a Regression: it works as expected in 4.7.6 ...

Implied Decal Blend Modes don't properly account for Material Attributes usage

UE - Graphics Features - Sep 28, 2021

I've attached a project with the necessary materials that demonstrate this issue. I would expect that just because a Set Material Attributes node is inside a material graph it wouldn't affect the de ...

Particles Do Not Obey Lighting Channels

UE - Niagara - Apr 17, 2018

Particle systems ignore lighting channels - no matter what channel a light is on (even if no channels are selected), it will affect lit particles. Changing lighting channels on the particle itself h ...

Packaged size of project is double its size when packaging for Shipping Windows (32 bit)

UE - Foundation - Core - Mar 9, 2015

When you package a project in 4.6.1 for Windows (32 bit) shipping, the file size is around 160 MB. When you package a sample project in 4.7.2, the packaged size will be around 345 MB. [Link Remove ...

SplineMeshComponent's collision will start to distort the longer the Spline becomes

UE - Gameplay - Nov 30, 2016

SplineMeshComponent's collision will start to distort the longer the Spline becomes This is a regession. It was working in 4.13.2-3172292 User Description: When drawing out a long spline mesh ( r ...

Sub Surface Shading Model has Strange Blotch Color Artifacts when Used with a Ambient Cubemap

UE - Graphics Features - Sep 23, 2019

Sub surface shading model has strange blotch color artifacts when used with ambient cubemap. Since the subsurface profile shading model can't be used with ambient cubemap I wanted to use the regular ...