ColorBaseConcept Struct Template Reference
[Concepts]

#include <gil_concept.hpp>

List of all members.

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Detailed Description

template<typename ColorBase>
struct boost::gil::ColorBaseConcept< ColorBase >

A color base is a container of color elements (such as channels, channel references or channel pointers).

COLOR BASE CONCEPTS The most common use of color base is in the implementation of a pixel, in which case the color elements are channel values. The color base concept, however, can be used in other scenarios. For example, a planar pixel has channels that are not contiguous in memory. Its reference is a proxy class that uses a color base whose elements are channel references. Its iterator uses a color base whose elements are channel iterators.

A color base must have an associated layout (which consists of a color space, as well as an ordering of the channels). There are two ways to index the elements of a color base: A physical index corresponds to the way they are ordered in memory, and a semantic index corresponds to the way the elements are ordered in their color space. For example, in the RGB color space the elements are ordered as {red_t, green_t, blue_t}. For a color base with a BGR layout, the first element in physical ordering is the blue element, whereas the first semantic element is the red one. Models of ColorBaseConcept are required to provide the at_c<K>(ColorBase) function, which allows for accessing the elements based on their physical order. GIL provides a semantic_at_c<K>(ColorBase) function (described later) which can operate on any model of ColorBaseConcept and returns the corresponding semantic element.

concept ColorBaseConcept<typename T> : CopyConstructible<T>, EqualityComparable<T> {
    // a GIL layout (the color space and element permutation)
    typename layout_t;     
        
    // The type of K-th element
    template <int K> struct kth_element_type;                 where Metafunction<kth_element_type>;
    
    // The result of at_c
    template <int K> struct kth_element_const_reference_type; where Metafunction<kth_element_const_reference_type>;        
    
    template <int K> kth_element_const_reference_type<T,K>::type at_c(T);

    // Copy-constructible and equality comparable with other compatible color bases
    template <ColorBaseConcept T2> where { ColorBasesCompatibleConcept<T,T2> } 
        T::T(T2);
    template <ColorBaseConcept T2> where { ColorBasesCompatibleConcept<T,T2> } 
        bool operator==(const T&, const T2&);
    template <ColorBaseConcept T2> where { ColorBasesCompatibleConcept<T,T2> } 
        bool operator!=(const T&, const T2&);

};

Public Member Functions
void	constraints ()
Public Attributes
ColorBase	cb

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

• gil_concept.hpp