Unreal Engine Issues
Unreal Engine Issues
Sphere Mask ArgInvHardness missing multiplication
UE - Rendering Architecture - Materials - Jun 27, 2025Hi Epic, In MaterialExpressions.cpp UMaterialExpressionSphereMask::Compile(), hardness is not calculated the same way in both <if> conditions. One is missing a multiplication by 0.01f. Specificall ...
Arrays in UMaterialEditorInstanceConstant are not updated
UE - Rendering Architecture - Materials - Jun 13, 2025Any UPROPERTY TArray added to UMaterialEditorInstanceConstant will not cause UI updates when elements are added or removed. This is caused by the custom validator created in FMaterialInstanceEditor ...
Multiple setter functions in UMaterialEditingLibrary always return false even when the parameter is correctly set on the MaterialInstance.
UE - Rendering Architecture - Materials - May 30, 2025In Unreal Engine, materials can expose parameters that can then be modified via instances (MaterialInstanceConstant). The UMaterialEditingLibrary provides several functions to modify these parameter ...
FHLSLMaterialTranslator::GetMaterialEnvironment can crash or not load UMaterialParameterCollections
UE - Rendering Architecture - Materials - Apr 30, 2025In UE 5.5, the Editor may crash in FHLSLMaterialTranslator::GetMaterialEnvironment when loading materials with Material Parameter Collections, likely due to async loading. Calling ParameterCollectio ...
Crash when attempting to change the parent of a material instance constant through editor scripting
UE - Rendering Architecture - Materials - Apr 9, 2025The built-in class "UMaterialEditingLibrary" provides various editor scripting functions related to creating and editing materials and material instances. One of these functions, UMaterialEditingLib ...
Sampling textures with bias in the path of a custom data pin causes derivative operations when avoidable
UE - Rendering Architecture - Materials - Apr 8, 2025Materials that make use of the analytical derivatives path to avoid hardware derivatives can still generate derivative operations on texture samples when the shading model has a custom data pin and ...
WPO bug with Material Layers
UE - Rendering Architecture - Materials - Apr 7, 2025I find that there are a couple of things that influence the artefact If WPO in M_BlendingBug is connected I get an issue with the blending. Removing the opacity input that's passed through the ma ...
Crash when Undo after deleting a Material Layer of a Material Instance.
UE - Rendering Architecture - Materials - Apr 2, 2025In Unreal Engine version 5.5.4, the Editor crashes when performing Undo after deleting a Material Layer of a Material Instance ...
Material Layers Relink Button Missing
UE - Rendering Architecture - Materials - Mar 26, 2025The Relink button is missing (as are the Save Sibling and Save Child buttons) on Material Instances that use Material Attributes Layers in 5.5. ...
High Virtual Texture Sample/Lookup Cost when using a Virtual Texture in a Material Layer Blend
UE - Rendering Architecture - Materials - Mar 14, 2025Some Material Attribute blends in Material Layer Blends can cause Virtual Texture samples to be duplicated in HLSL. This can be avoided by sampling the Virtual Texture in the Parent Material, and pa ...