Transform a point-dependent (and possibly domain-dependent) functor into a constant image. More...

#include <DGtal/images/ConstImageFunctorHolder.h>

Data Structures
class	ConstRange
	Constant range on a ConstImageFunctorHolder. More...

Public Types
using	Self = ConstImageFunctorHolder<TDomain, TValue, TFunctor>
using	Domain = TDomain
using	Point = typename Domain::Point
using	Vector = typename Domain::Vector
using	Integer = typename Domain::Integer
using	Size = typename Domain::Size
using	Dimension = typename Domain::Dimension
using	Vertex = Point
using	Value = TValue
using	Functor = TFunctor
using	ConstIterator = boost::transform_iterator< std::reference_wrapper<const Self>, typename Domain::ConstIterator >
using	ConstReverseIterator = boost::reverse_iterator< ConstIterator >

Public Member Functions
	BOOST_STATIC_CONSTANT (Dimension, dimension=Domain::Space::dimension)
template<class TGivenFunctor>
	ConstImageFunctorHolder (Domain const &aDomain, TGivenFunctor &&aFunctor)
	Constructor.
Domain const &	domain () const
	Returns the associated domain.
template<typename TPoint>
auto	operator() (TPoint const &aPoint) const -> decltype(myFunctor(aPoint))
	Evaluates the functor at the given point.
template<typename TPoint>
auto	operator() (TPoint const &aPoint) const -> decltype(myFunctor(aPoint, myDomain))
ConstRange	constRange () const
	Returns a constant range over this image.
void	selfDisplay (std::ostream &out) const
	Writes/Displays the object on an output stream.
constexpr bool	isValid () const
	Checks the validity/consistency of the object.

Private Member Functions
	BOOST_CONCEPT_ASSERT ((DGtal::concepts::CDomain< TDomain >))

Private Attributes
Domain	myDomain
	The image domain.
Functor	myFunctor
	The functor that generates the image.

Detailed Description

template<typename TDomain, typename TValue, typename TFunctor>
class DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >

Transform a point-dependent (and possibly domain-dependent) functor into a constant image.

Template Parameters

TDomain	Domain type.
TValue	Value type returned by the functor.
TFunctor	Type of the functor.

The functor must accept a point, and eventually a domain, and return a value whose type is Value.

Warning: This class is not meant to be directly constructed by the user. As illustrated below, use instead the holdConstImageFunctor helper that will choose the more appropriate storage type for the functor depending on the given callable object.

A typical usage would be:

  const Domain domain1(Point(1,1), Point(16,16));
 
  auto image1 = DGtal::functors::holdConstImageFunctor(
      domain1,
      [] (Point const& pt) { return 25 * ( std::cos( (pt - Point(4,4)).norm() ) + 1 ); }
  );

resulting in:

Image generated from a point-dependent lambda.

In you want to use a function instead of a functor or lambda, consider wrapping it into a lambda to avoid a performance penalty due to the fact that a pointer to a function cannot be inlined:

auto image = DGtal::holdConstImageFunctor(
    domain,
    [] (Point const& pt) { return my_function(pt); }
);

This example is illustrated in Constant image from a function, functor or lambda and you can find more informations about how to use this class appropriately in the module about Using functions, functors and lambdas in DGtal .

See also: holdConstImageFunctor, FunctorHolder, Using functions, functors and lambdas in DGtal; exampleConstImageFunctorHolder.cpp

Definition at line 104 of file ConstImageFunctorHolder.h.

Member Typedef Documentation

◆ ConstIterator

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::ConstIterator = boost::transform_iterator< std::reference_wrapper<const Self>, typename Domain::ConstIterator >

Definition at line 123 of file ConstImageFunctorHolder.h.

◆ ConstReverseIterator

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::ConstReverseIterator = boost::reverse_iterator< ConstIterator >

Definition at line 124 of file ConstImageFunctorHolder.h.

◆ Dimension

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Dimension = typename Domain::Dimension

Definition at line 118 of file ConstImageFunctorHolder.h.

◆ Domain

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Domain = TDomain

Definition at line 113 of file ConstImageFunctorHolder.h.

◆ Functor

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Functor = TFunctor

Definition at line 121 of file ConstImageFunctorHolder.h.

◆ Integer

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Integer = typename Domain::Integer

Definition at line 116 of file ConstImageFunctorHolder.h.

◆ Point

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Point = typename Domain::Point

Definition at line 114 of file ConstImageFunctorHolder.h.

◆ Self

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Self = ConstImageFunctorHolder<TDomain, TValue, TFunctor>

Definition at line 112 of file ConstImageFunctorHolder.h.

◆ Size

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Size = typename Domain::Size

Definition at line 117 of file ConstImageFunctorHolder.h.

◆ Value

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Value = TValue

Definition at line 120 of file ConstImageFunctorHolder.h.

◆ Vector

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Vector = typename Domain::Vector

Definition at line 115 of file ConstImageFunctorHolder.h.

◆ Vertex

template<typename TDomain, typename TValue, typename TFunctor>

using DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::Vertex = Point

Definition at line 119 of file ConstImageFunctorHolder.h.

Constructor & Destructor Documentation

◆ ConstImageFunctorHolder()

template<typename TDomain, typename TValue, typename TFunctor>

template<class TGivenFunctor>

DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::ConstImageFunctorHolder	(	Domain const &	aDomain,
		TGivenFunctor &&	aFunctor )

inlineexplicit

Constructor.

Parameters

aDomain	The domain of the image.
aFunctor	The functor taking point as parameter.

Definition at line 144 of file ConstImageFunctorHolder.h.

    : myDomain( aDomain )
    , myFunctor( std::forward<TGivenFunctor>(aFunctor) )
  {
  }

References myDomain, and myFunctor.

Member Function Documentation

◆ BOOST_CONCEPT_ASSERT()

template<typename TDomain, typename TValue, typename TFunctor>

DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::BOOST_CONCEPT_ASSERT ( (DGtal::concepts::CDomain< TDomain >) )

private

◆ BOOST_STATIC_CONSTANT()

template<typename TDomain, typename TValue, typename TFunctor>

DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::BOOST_STATIC_CONSTANT	(	Dimension	,
		dimension	= Domain::Space::dimension )

◆ constRange()

template<typename TDomain, typename TValue, typename TFunctor>

ConstRange DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::constRange ( ) const

inline

Returns a constant range over this image.

Definition at line 198 of file ConstImageFunctorHolder.h.

    {
      return ConstRange( *this );
    }

◆ domain()

template<typename TDomain, typename TValue, typename TFunctor>

Domain const & DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::domain ( ) const

inline

Returns the associated domain.

Definition at line 155 of file ConstImageFunctorHolder.h.

    {
      return myDomain;
    }

References myDomain.

◆ isValid()

template<typename TDomain, typename TValue, typename TFunctor>

bool DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::isValid ( ) const

inlineconstexpr

Checks the validity/consistency of the object.

Returns: 'true' if the object is valid, 'false' otherwise.

Definition at line 216 of file ConstImageFunctorHolder.h.

    {
      return true;
    }

◆ operator()() [1/2]

template<typename TDomain, typename TValue, typename TFunctor>

template<typename TPoint>

auto DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::operator() ( TPoint const & aPoint ) const -> decltype( myFunctor( aPoint ) )

inline

Evaluates the functor at the given point.

Template Parameters

TPoint point type (auto-deduced).

Parameters

aPoint the point.

Returns: the value at aPoint.

Note: There are two overloads of this operator, automatically dispatched depending on the arity of the functor.

Definition at line 171 of file ConstImageFunctorHolder.h.

    {
      ASSERT_MSG(
          myDomain.isInside(aPoint),
          "The point is outside the domain."
      );
      return myFunctor( aPoint );
    }

References aPoint, myDomain, and myFunctor.

◆ operator()() [2/2]

template<typename TDomain, typename TValue, typename TFunctor>

template<typename TPoint>

auto DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::operator() ( TPoint const & aPoint ) const -> decltype( myFunctor( aPoint, myDomain ) )

inline

Definition at line 183 of file ConstImageFunctorHolder.h.

    {
      ASSERT_MSG(
          myDomain.isInside(aPoint),
          "The point is outside the domain."
      );
      return myFunctor( aPoint, myDomain );
    }

References aPoint, myDomain, and myFunctor.

◆ selfDisplay()

template<typename TDomain, typename TValue, typename TFunctor>

void DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::selfDisplay ( std::ostream & out ) const

inline

Writes/Displays the object on an output stream.

Parameters

out	the output stream where the object is written.

Definition at line 207 of file ConstImageFunctorHolder.h.

    {
      out << "[ConstImageFunctorHolder] holding a " << myFunctor << " on domain " << myDomain;
    }

References myDomain, and myFunctor.

Field Documentation

◆ myDomain

template<typename TDomain, typename TValue, typename TFunctor>

Domain DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::myDomain

private

The image domain.

Definition at line 133 of file ConstImageFunctorHolder.h.

Referenced by ConstImageFunctorHolder(), domain(), operator()(), operator()(), and selfDisplay().

◆ myFunctor

template<typename TDomain, typename TValue, typename TFunctor>

Functor DGtal::functors::ConstImageFunctorHolder< TDomain, TValue, TFunctor >::myFunctor

private

The functor that generates the image.

Definition at line 134 of file ConstImageFunctorHolder.h.

Referenced by ConstImageFunctorHolder(), operator()(), operator()(), and selfDisplay().

The documentation for this class was generated from the following file:

ConstImageFunctorHolder.h

Data Structures

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ ConstIterator

◆ ConstReverseIterator

◆ Dimension

◆ Domain

◆ Functor

◆ Integer

◆ Point

◆ Self

◆ Size

◆ Value

◆ Vector

◆ Vertex

Constructor & Destructor Documentation

◆ ConstImageFunctorHolder()

Member Function Documentation

◆ BOOST_CONCEPT_ASSERT()

◆ BOOST_STATIC_CONSTANT()

◆ constRange()

◆ domain()

◆ isValid()

◆ operator()() [1/2]

◆ operator()() [2/2]

◆ selfDisplay()

Field Documentation

◆ myDomain

◆ myFunctor