Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)

UE - Rendering Architecture - Materials - Jun 25, 2024

Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...

Can't set "r.Shaders.Optimize" to false in UE5.4

UE - Rendering Architecture - Shaders - Jun 7, 2024

The CVar "r.Shaders.Optimize" cannot be set to false from DefaultEngine.ini in the section "[ShaderCompiler]" as its help text describes. Also tested on UE5-Main, CL: 34200103 ...

Problem with material layers using interpolator nodes

UE - Rendering Architecture - Materials - Jun 7, 2024

The Vertex Interpolator Material Expression appears to collapse separate instances from separate Material Layers, leading to visual artifacts when used. Also tested on UE5_Main, CL: 34200103 ...

Instanced object in an array property of an actor component is invalidated and marked for garbage collection on undo

UE - Gameplay - Jun 4, 2024

If an actor component contains a TArray of instanced objects, some of those object instances can get incorrectly invalidated and marked for garbage collection in certain situations, possibly resulti ...

Displacement + TAA causes "vibrating"/"buzzing" artifacts

UE - Rendering Architecture - Jun 4, 2024

There is a buzzing artifact on shadows that is seen in the provided test project. The problem seems to be far more subtle when VSM is turned off. Licensee mentions that turning r.Velocity.ForceOutpu ...

Strange results with HeightToNormalSmooth on Nanite meshes

UE - Rendering Architecture - Jun 3, 2024

This appears to also occur on meshes that aren't set to Enable Nanite at all.  [Image Removed] ...

Bright Flickering or Black Squares with Rectangle Lights Intersecting Meshes

UE - Graphics Features - May 31, 2024

Rect Lights that intersect geometry can produce NaN pixels in SceneColor, which will affect bloom, FXAA, and other future passes. This can lead to large visible artifacts. The NaN values are produc ...

Nested level visibility track bug

UE - Anim - Sequencer - May 31, 2024

The Level Visibility tracks part of a Subsequence are turned off every time you save the Leve Sequence. It does not happen if Level Visibility tracks are added in the main Sequence. ...

Memory stomp in UTexture2DArray::SetPlatformData

UE - Texture - May 30, 2024

A crash from bad memory access can happen when clearing the textures in a Texture2DArray asset. This appears to be because the order of operations when deleting the platform data is: ``` if (Privat ...

Custom mode animation resets character pose on every change in the Sequencer

UE - Anim - Sequencer - May 30, 2024

Skeletal Mesh Components that use Custom Animation Mode will have their animation rest to the base position when any change is made to the Level Sequence that the character is used in. The Licensee ...