static [EVisibility](API\Runtime\SlateCore\Layout\EVisibility) ShouldShowExpression ( [UDEditorParameterValue](API\Editor\UnrealEd\MaterialEditor\UDEditorParameterValue) * Parameter, [UMaterialEditorInstanceConstant](API\Editor\UnrealEd\MaterialEditor\UMaterialEditorInstanceConstant) * MaterialEditorInstance, FGetShowHiddenParameters ShowHiddenDelegate )