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> Unreal Engine API Reference > Runtime > Engine > Materials > UMaterialFunction

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UMaterialFunction

A Material Function is a collection of material expressions that can be reused in different materials

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Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UMaterialFunctionInterface

UMaterialFunction

	UMaterialFunctionMaterialLayer
	UMaterialFunctionMaterialLayerBlend

References

Module	Engine
Header	/Engine/Source/Runtime/Engine/Classes/Materials/MaterialFunction.h
Include	#include "Materials/MaterialFunction.h"

Syntax

class UMaterialFunction : public UMaterialFunctionInterface

Remarks

A Material Function is a collection of material expressions that can be reused in different materials

Variables

	Name	Description
uint8: 1	bExposeToLibrary	Whether to list this function in the material function library, which is a window in the material editor that lists categorized functions.
uint8: 1	bPrefixParameterNames	If true, parameters in this function will have a prefix added to their group name.
TArray< TObject...	DependentFunctionExpressionCandidates
FString	Description	Description of the function which will be displayed as a tooltip wherever the function is used.
TArray< TObject...	FunctionEditorComments	Array of comments associated with this material; viewed in the material editor.
TArray< TObject...	FunctionExpressions	Array of material expressions, excluding Comments. Used by the material editor.
TArray< FText >	LibraryCategoriesText	Categories that this function belongs to in the material function library.
TObjectPtr< cla...	ParentFunction	Used in the material editor, points to the function asset being edited, which this function is just a preview for.
TEnumAsByte< en...	PreviewBlendMode	Determines the blend mode when previewing a material function.
TObjectPtr< UMa...	PreviewMaterial

Constructors

	Name	Description
	UMaterialFunction ( const FObjectInitializer& ObjectIn... )

Functions

		Name	Description
	bool	SetFontParameterValueEditorOnly ( FName ParameterName, UFont* InFontValue, int32 InFontPage )
	void	SetMaterialFunctionUsage ( EMaterialFunctionUsage Usage )
	bool	SetParameterValueEditorOnly ( const FName& ParameterName, const FMaterialParameterMetadata& ... )
	bool	SetRuntimeVirtualTextureParameterValueEditorOnly ( FName ParameterName, URuntimeVirtualTexture* InValu... )
	bool	SetScalarParameterValueEditorOnly ( FName ParameterName, float InValue )
	bool	SetStaticComponentMaskParameterValueEditorOnly ( FName ParameterName, bool R, bool G, bool B, bool A, FGuid OutExpressionGuid )
	bool	SetStaticSwitchParameterValueEditorOnly ( FName ParameterName, bool OutValue, FGuid OutExpressionGuid )
	bool	SetTextureParameterValueEditorOnly ( FName ParameterName, UTexture* InValue )
	bool	SetVectorParameterValueEditorOnly ( FName ParameterName, FLinearColor InValue )
	void	UpdateDependentFunctionCandidates()

Overridden from UMaterialFunctionInterface

	Name	Description
int32	Compile ( FMaterialCompiler* Compiler, const FFunctionExpressionOutput& O... )
void	ForceRecompileForRendering ( FMaterialUpdateContext& UpdateCont..., UMaterial* InPreviewMaterial )
UMaterialFun...	GetBaseFunction()
const UMater...	GetBaseFunction()
void	GetDependentFunctions ( TArray< UMaterialFunctionInterface ... )	Returns an array of the functions that this function is dependent on, directly or indirectly.
const FStrin...	GetDescription()
const TArray...	GetFunctionExpressions()
void	GetInputsAndOutputs ( TArray< struct FFunctionExpressionI..., TArray< struct FFunctionExpressionO... )	Get the inputs and outputs that this function exposes, for a function call expression to use.
EMaterialFun...	GetMaterialFunctionUsage()
UMaterialInt...	GetPreviewMaterial()
bool	GetReentrantFlag()
bool	HasFlippedCoordinates()	Checks whether a Material Function is arranged in the old style, with inputs flowing from right to left
bool	IsDependent ( UMaterialFunctionInterface* Ot... )
bool	IterateDependentFunctions ( TFunctionRef< bool... )	Iterates all functions that this function is dependent on, directly or indrectly.
void	LinkIntoCaller ( const TArray< FFunctionExpressionIn... )	Called during compilation before entering the function.
void	SetReentrantFlag ( const bool bIsReentrant )
void	UnlinkFromCaller()
void	UpdateFromFunctionResource()	Recursively update all function call expressions in this function, or in nested functions.
void	UpdateInputOutputTypes()
bool	ValidateFunctionUsage ( FMaterialCompiler* Compiler, const FFunctionExpressionOutput& O... )

Overridden from UObject

	Name	Description
void	PostEditChangeProperty ( FPropertyChangedEvent& PropertyCha... )	Called when a property on this object has been modified externally
void	PostLoad()	Do any object-specific cleanup required immediately after loading an object.
void	Serialize ( FArchive& Ar )	Handles reading, writing, and reference collecting using FArchive.

Deprecated Variables

		Name	Description
	TArray< FString...	LibraryCategories_DEPRECATED	Categories that this function belongs to in the material function library.