argb.h

#ifndef CVD_QT_ARGB_H
#define CVD_QT_ARGB_H

#include <iostream>

namespace CVD
{

// CVD::Argb
// Template class to represent red, green, blue and alpha components
//
template <typename T>
class Argb
{
    public:
    explicit Argb()
        : red(0)
        , green(0)
        , blue(0)
        , alpha(0)
    {
    }

    explicit Argb(T a, T r, T g, T b)
        : red(r)
        , green(g)
        , blue(b)
        , alpha(a)
    {
    }

    T blue; 
    T green; 
    T red; 
    T alpha; 

    template <typename T2>
    Argb<T>& operator=(const Argb<T2>& c)
    {
        red = static_cast<T>(c.red);
        green = static_cast<T>(c.green);
        blue = static_cast<T>(c.blue);
        alpha = static_cast<T>(c.alpha);
        return *this;
    }

    bool operator==(const Argb<T>& c) const
    {
        return red == c.red && green == c.green && blue == c.blue && alpha == c.alpha;
    }

    bool operator!=(const Argb<T>& c) const
    {
        return red != c.red || green != c.green || blue != c.blue || alpha != c.alpha;
    }

    //   T to_grey() const {return 0.3*red + 0.6*green + 0.1*blue;}
};

template <typename T>
std::ostream& operator<<(std::ostream& os, const Argb<T>& x)
{
    return os << "(" << x.alpha << "," << x.red << ","
              << x.green << "," << x.blue << ")";
}

inline std::ostream& operator<<(std::ostream& os, const Argb<unsigned char>& x)
{
    return os << "(" << static_cast<unsigned int>(x.alpha) << ","
              << static_cast<unsigned int>(x.red) << ","
              << static_cast<unsigned int>(x.green) << ","
              << static_cast<unsigned int>(x.blue) << ")";
}

} // end namespace
#endif