QskHctColor.h

/******************************************************************************
 * QSkinny - Copyright (C) The authors
 *           SPDX-License-Identifier: BSD-3-Clause
 *****************************************************************************/
 
#ifndef QSK_HCT_COLOR_H
#define QSK_HCT_COLOR_H
 
#include "QskGlobal.h"
#include <qcolor.h>
 
/*
    For M(aterial)3 the new HTC color system has been created, that
    is based on H(ue), (C)hroma, (T)one:
 
        https://material.io/blog/science-of-color-design
 
    This system allows to create color palettes by varying the tone
    for given hue/chroma values.
 
    https://material-foundation.github.io/material-theme-builder/#/custom
    shows how to create a tonal palette from a given RGB color.
 */
 
class QSK_EXPORT QskHctColor
{
  public:
    constexpr QskHctColor() noexcept = default;
    constexpr QskHctColor( qreal hue, qreal chrome, qreal tone = 40 ) noexcept;
 
    QskHctColor( QRgb );
 
    void setHue( qreal hue );
    constexpr qreal hue() const noexcept;
 
    void setChroma( qreal chroma ) noexcept;
    constexpr qreal chroma() const noexcept;
 
    void setTone( qreal tone ) noexcept;
    constexpr qreal tone() const noexcept;
 
    constexpr QskHctColor toned( qreal tone ) const noexcept;
 
    void setRgb( QRgb );
    QRgb rgb() const;
 
  private:
    qreal m_hue = 0;    // [0.0, 360.0[
    qreal m_chroma = 0;
    qreal m_tone = 0;   // [0.0, 100.0]
};
 
Q_DECLARE_TYPEINFO( QskHctColor, Q_MOVABLE_TYPE );
 
inline constexpr QskHctColor::QskHctColor( qreal hue, qreal chroma, qreal tone ) noexcept
    : m_hue( hue )
    , m_chroma( chroma )
    , m_tone( tone )
{
}
 
inline constexpr qreal QskHctColor::hue() const noexcept
{
    return m_hue;
}
 
inline constexpr qreal QskHctColor::chroma() const noexcept
{
    return m_chroma;
}
 
inline constexpr qreal QskHctColor::tone() const noexcept
{
    return m_tone;
}
 
inline constexpr QskHctColor QskHctColor::toned( qreal tone ) const noexcept
{
    return QskHctColor( m_hue, m_chroma, tone );
}
 
#ifndef QT_NO_DEBUG_STREAM
 
    class QDebug;
    QSK_EXPORT QDebug operator<<( QDebug, const QskHctColor& );
 
#endif
 
#endif