DatasmithMaterialElements.h

// Copyright 1998-2019 Epic Games, Inc. All Rights Reserved.
#pragma once
 
#include "IDatasmithSceneElements.h"
 
class IDatasmithMaterialExpression;
 
class IDatasmithExpressionInput
{
public:
    virtual const TCHAR* GetInputName() const = 0;
 
    virtual IDatasmithMaterialExpression* GetExpression() = 0;
    virtual const IDatasmithMaterialExpression* GetExpression() const = 0;
    virtual void SetExpression( IDatasmithMaterialExpression* InExpression ) = 0;
 
    virtual int32 GetOutputIndex() const = 0;
    virtual void SetOutputIndex( int32 InOutputIndex ) = 0;
};
 
class IDatasmithExpressionOutput
{
public:
    virtual ~IDatasmithExpressionOutput() = default;
 
    virtual const TCHAR* GetOutputName() const = 0;
    virtual void SetOutputName( const TCHAR* InOutputName ) = 0;
};
 
class IDatasmithExpressionParameter
{
public:
    virtual ~IDatasmithExpressionParameter() = default;
 
    virtual const TCHAR* GetGroupName() const = 0;
    virtual void SetGroupName( const TCHAR* InGroupName ) = 0;
};
 
enum class EDatasmithMaterialExpressionType
{
    ConstantBool,
    ConstantColor,
    ConstantScalar,
    FlattenNormal,
    FunctionCall,
    Generic,
    Texture,
    TextureCoordinate
};
 
class IDatasmithMaterialExpression
{
public:
    virtual ~IDatasmithMaterialExpression() = default;
 
    /** The name of the expression. Used as parameter name for material instances. */
    virtual const TCHAR* GetName() const = 0;
    virtual void SetName( const TCHAR* InName ) = 0;
 
    virtual EDatasmithMaterialExpressionType GetType() const = 0;
    bool IsA( const EDatasmithMaterialExpressionType ExpressionType ) const { return ExpressionType == GetType(); }
 
    /** Connects the default output to an expression input */
    virtual void ConnectExpression( IDatasmithExpressionInput& ExpressionInput ) = 0;
 
    /** Connects a specific output to an expression input */
    virtual void ConnectExpression( IDatasmithExpressionInput& ExpressionInput, int32 OutputIndex ) = 0;
 
    virtual int32 GetInputCount() const = 0;
    virtual IDatasmithExpressionInput* GetInput( int32 Index ) = 0;
    virtual const IDatasmithExpressionInput* GetInput( int32 Index ) const = 0;
 
    /** The output index to use by default for this expression when connecting it to other inputs. */
    virtual int32 GetDefaultOutputIndex() const = 0;
    virtual void SetDefaultOutputIndex( int32 OutputIndex ) = 0;
};
 
/**
 * Represents a UMaterialExpressionStaticBoolParameter
 */
class IDatasmithMaterialExpressionBool : public IDatasmithMaterialExpression, public IDatasmithExpressionParameter
{
public:
    virtual bool& GetBool() = 0;
    virtual const bool& GetBool() const = 0;
};
 
class IDatasmithMaterialExpressionColor : public IDatasmithMaterialExpression, public IDatasmithExpressionParameter
{
public:
    virtual FLinearColor& GetColor() = 0;
    virtual const FLinearColor& GetColor() const = 0;
};
 
class IDatasmithMaterialExpressionScalar : public IDatasmithMaterialExpression, public IDatasmithExpressionParameter
{
public:
    virtual float& GetScalar() = 0;
    virtual const float& GetScalar() const = 0;
};
 
class IDatasmithMaterialExpressionTexture : public IDatasmithMaterialExpression, public IDatasmithExpressionParameter
{
public:
    virtual const TCHAR* GetTexturePathName() const = 0;
    virtual void SetTexturePathName( const TCHAR* InTexturePathName ) = 0;
 
    /**
     * Inputs
     */
    virtual IDatasmithExpressionInput& GetInputCoordinate() = 0;
    virtual const IDatasmithExpressionInput& GetInputCoordinate() const = 0;
 
    /**
     * Outputs:
     * - RGB
     * - R
     * - G
     * - B
     * - A
     */
};
 
class IDatasmithMaterialExpressionTextureCoordinate : public IDatasmithMaterialExpression
{
public:
    virtual int32 GetCoordinateIndex() const = 0;
    virtual void SetCoordinateIndex( int32 InCoordinateIndex ) = 0;
 
    virtual float GetUTiling() const = 0;
    virtual void SetUTiling( float InUTiling ) = 0;
 
    virtual float GetVTiling() const = 0;
    virtual void SetVTiling( float InCoordinateIndex ) = 0;
};
 
class IDatasmithMaterialExpressionFlattenNormal : public IDatasmithMaterialExpression
{
public:
    /** 
     * Inputs
     */
    virtual IDatasmithExpressionInput& GetNormal() = 0;
    virtual const IDatasmithExpressionInput& GetNormal() const = 0;
 
    virtual IDatasmithExpressionInput& GetFlatness() = 0;
    virtual const IDatasmithExpressionInput& GetFlatness() const = 0;
 
    /**
     * Outputs:
     * - RGB
     */
};
 
class IDatasmithMaterialExpressionGeneric : public IDatasmithMaterialExpression
{
public:
    virtual void SetExpressionName( const TCHAR* InExpressionName ) = 0;
    virtual const TCHAR* GetExpressionName() const = 0;
 
    /** Get the total amount of properties in this expression */
    virtual int32 GetPropertiesCount() const = 0;
 
    /** Get the property i-th of this expression */
    virtual const TSharedPtr< IDatasmithKeyValueProperty >& GetProperty(int32 i) const = 0;
    virtual TSharedPtr< IDatasmithKeyValueProperty >& GetProperty(int32 i) = 0;
 
    /** Get a property by its name if it exists */
    virtual const TSharedPtr< IDatasmithKeyValueProperty >& GetPropertyByName(const TCHAR* Name) const = 0;
    virtual TSharedPtr< IDatasmithKeyValueProperty >& GetPropertyByName(const TCHAR* Name) = 0;
 
    /** Add a property to this expression*/
    virtual void AddProperty( const TSharedPtr< IDatasmithKeyValueProperty >& Property ) = 0;
};
 
class IDatasmithMaterialExpressionFunctionCall : public IDatasmithMaterialExpression
{
public:
    virtual void SetFunctionPathName( const TCHAR* InFunctionPathName ) = 0;
    virtual const TCHAR* GetFunctionPathName() const = 0;
 
};
 
class DATASMITHCORE_API IDatasmithUEPbrMaterialElement : public IDatasmithBaseMaterialElement
{
public:
    virtual IDatasmithExpressionInput& GetBaseColor() = 0;
    virtual IDatasmithExpressionInput& GetMetallic() = 0;
    virtual IDatasmithExpressionInput& GetSpecular() = 0;
    virtual IDatasmithExpressionInput& GetRoughness() = 0;
    virtual IDatasmithExpressionInput& GetEmissiveColor() = 0;
    virtual IDatasmithExpressionInput& GetOpacity() = 0;
    virtual IDatasmithExpressionInput& GetNormal() = 0;
    virtual IDatasmithExpressionInput& GetWorldDisplacement() = 0;
    virtual IDatasmithExpressionInput& GetRefraction() = 0;
    virtual IDatasmithExpressionInput& GetAmbientOcclusion() = 0;
    virtual IDatasmithExpressionInput& GetMaterialAttributes() = 0;
 
    virtual int GetBlendMode() const = 0;
    virtual void SetBlendMode( int bInBlendMode ) = 0;
 
    virtual bool GetTwoSided() const = 0;
    virtual void SetTwoSided( bool bTwoSided ) = 0;
 
    virtual bool GetUseMaterialAttributes() const = 0;
    virtual void SetUseMaterialAttributes( bool bInUseMaterialAttributes ) = 0;
 
    /** If a material is only referenced by other materials then it is only used as a material function and there is no need to instantiate it. */
    virtual bool GetMaterialFunctionOnly() const = 0;
    virtual void SetMaterialFunctionOnly(bool bInMaterialFunctionOnly) = 0;
 
    virtual int32 GetExpressionsCount() const = 0;
    virtual IDatasmithMaterialExpression* GetExpression( int32 Index ) = 0;
    virtual int32 GetExpressionIndex( const IDatasmithMaterialExpression* Expression ) const = 0;
 
    virtual IDatasmithMaterialExpression* AddMaterialExpression( const EDatasmithMaterialExpressionType ExpressionType ) = 0;
 
    template< typename T >
    T* AddMaterialExpression()
    {
    }
 
    /** If a parent material is generated from this material, this will be its label. If none, the instance and the parent will have the same label. */
    virtual void SetParentLabel( const TCHAR* InParentLabel ) = 0;
    virtual const TCHAR* GetParentLabel() const = 0;
};
 
template<>
inline IDatasmithMaterialExpressionBool* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionBool >()
{
    return static_cast< IDatasmithMaterialExpressionBool* >( AddMaterialExpression( EDatasmithMaterialExpressionType::ConstantBool ) );
}
 
template<>
inline IDatasmithMaterialExpressionColor* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionColor >()
{
    return static_cast< IDatasmithMaterialExpressionColor* >( AddMaterialExpression( EDatasmithMaterialExpressionType::ConstantColor ) );
}
 
template<>
inline IDatasmithMaterialExpressionFlattenNormal* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionFlattenNormal >()
{
    return static_cast< IDatasmithMaterialExpressionFlattenNormal* >( AddMaterialExpression( EDatasmithMaterialExpressionType::FlattenNormal ) );
}
 
template<>
inline IDatasmithMaterialExpressionFunctionCall* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionFunctionCall >()
{
    return static_cast< IDatasmithMaterialExpressionFunctionCall* >( AddMaterialExpression( EDatasmithMaterialExpressionType::FunctionCall ) );
}
 
template<>
inline IDatasmithMaterialExpressionGeneric* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionGeneric >()
{
    return static_cast< IDatasmithMaterialExpressionGeneric* >( AddMaterialExpression( EDatasmithMaterialExpressionType::Generic ) );
}
 
template<>
inline IDatasmithMaterialExpressionScalar* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionScalar >()
{
    return static_cast< IDatasmithMaterialExpressionScalar* >( AddMaterialExpression( EDatasmithMaterialExpressionType::ConstantScalar ) );
}
 
template<>
inline IDatasmithMaterialExpressionTexture* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionTexture >()
{
    return static_cast< IDatasmithMaterialExpressionTexture* >( AddMaterialExpression( EDatasmithMaterialExpressionType::Texture ) );
}
 
template<>
inline IDatasmithMaterialExpressionTextureCoordinate* IDatasmithUEPbrMaterialElement::AddMaterialExpression< IDatasmithMaterialExpressionTextureCoordinate >()
{
    return static_cast< IDatasmithMaterialExpressionTextureCoordinate* >( AddMaterialExpression( EDatasmithMaterialExpressionType::TextureCoordinate ) );
}