Unreal Engine Issues

Invalid PropertyConnectedMask in layered material instance when base material doesn't use material attributes

When UMaterialInstanceConstant::UpdateCachedData() updates CachedExpressionData.PropertyConnectedMask for material instances with layers incorrectly, it can lead to various graphical issues includin ...

'prefix parameter names' checkbox in a material function's settings does nothing.

Prefix Parameter Names checkbox does not work as expected, and the Group names are unmodified. The value "UMaterialFunction::bPrefixParameterNames" does not appear to be used anywhere in the Engine ...

Material attribute layers issue with texture sample and VT lookups

When using material attribute layers in a material layer setup, there is a potential discrepancy in the number of VT Lookups presented in the material instance's Platform Stats. When the same textur ...

Null Material Layers in Material Instances cause Opacity Mask and WPO to break on Nanite Meshes

When a Material Instance is loaded that has a nullptr layer in StaticParametrs.Materiallayers.  The Material Instance will create it's own CachedExpressionData but the ConnectedParameterMask will be ...

Calling GetMaterial during compile on load can cause the material shader to fail to compile

Calling UStaticMeshComponent::GetMaterial() during a Blueprint compile on load can cause the Material shader to fail to compile because GetMaterial will trigger a PostLoad call on that Material and ...

Material Graph Editor crash when changing the value of a node entering a reentrant expression

It is possible to cause an editor crash when changing a the value of a node involved with a reentrant expression. See the steps to reproduce for more information. Specifically, the crash occurs whe ...

Material functions should be able to output the same data as it can accept as inputs

Material Functions cannot output Texture Objects or Booleans. This seems to be because the Material Editor believes that the outputs are Floats, and forbid connections to inputs that take Textures ...

Check for sRGB on Normal and Mask samplers instead checks against Greyscale and Alpha samplers

In FMaterialInstanceEditor::RefreshOnScreenMessages, there is a check for sRGB on Normal and Mask samplers. The issue is the check uses a TextureCompressionSettings enum cast to EMaterialSamplerTyp ...

r.Shaders.Optimize=0 crashes when compiling a UI material

[2024.08.30-22.12.22:384][ 73]LogWindows: Error: appError called: Assertion failed: CurrentGPUVirtualAddress != 0 [Link Removed] [Line: 659] Disabling shader optimisation can crash the editor when ...

Material Layering sometimes increses Shader complexity significently