qmargins.h

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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#ifndef QMARGINS_H
#define QMARGINS_H
 
#include <QtCore/qcheckedint_impl.h>
#include <QtCore/qcompare.h>
#include <QtCore/qnamespace.h>
 
#include <QtCore/q20type_traits.h>
#include <QtCore/q23utility.h>
 
QT_BEGIN_NAMESPACE
 
QT_ENABLE_P0846_SEMANTICS_FOR(get)
 
class QDataStream;
class QMarginsF;
 
/*****************************************************************************
  QMargins class
 *****************************************************************************/
 
class QMargins
{
public:
    constexpr QMargins() noexcept;
    constexpr QMargins(int left, int top, int right, int bottom) noexcept;
 
    constexpr bool isNull() const noexcept;
 
    constexpr int left() const noexcept;
    constexpr int top() const noexcept;
    constexpr int right() const noexcept;
    constexpr int bottom() const noexcept;
 
    constexpr void setLeft(int left) noexcept;
    constexpr void setTop(int top) noexcept;
    constexpr void setRight(int right) noexcept;
    constexpr void setBottom(int bottom) noexcept;
 
    constexpr QMargins &operator+=(const QMargins &margins) noexcept;
    constexpr QMargins &operator-=(const QMargins &margins) noexcept;
    constexpr QMargins &operator+=(int) noexcept;
    constexpr QMargins &operator-=(int) noexcept;
    constexpr QMargins &operator*=(int) noexcept;
    constexpr QMargins &operator/=(int);
    constexpr QMargins &operator*=(qreal) noexcept;
    constexpr QMargins &operator/=(qreal);
 
    [[nodiscard]] constexpr inline QMarginsF toMarginsF() const noexcept;
 
    friend constexpr inline QMargins operator+(const QMargins &m1, const QMargins &m2) noexcept;
    friend constexpr inline QMargins operator-(const QMargins &m1, const QMargins &m2) noexcept;
    friend constexpr inline QMargins operator+(const QMargins &lhs, int rhs) noexcept;
    friend constexpr inline QMargins operator+(int lhs, const QMargins &rhs) noexcept;
    friend constexpr inline QMargins operator-(const QMargins &lhs, int rhs) noexcept;
    friend constexpr inline QMargins operator*(const QMargins &margins, int factor) noexcept;
    friend constexpr inline QMargins operator*(int factor, const QMargins &margins) noexcept;
    friend constexpr inline QMargins operator*(const QMargins &margins, qreal factor) noexcept;
    friend constexpr inline QMargins operator*(qreal factor, const QMargins &margins) noexcept;
    friend constexpr inline QMargins operator/(const QMargins &margins, int divisor);
    friend constexpr inline QMargins operator/(const QMargins &margins, qreal divisor);
    friend constexpr inline QMargins operator|(const QMargins &m1, const QMargins &m2) noexcept;
 
private:
    using Representation = QtPrivate::QCheckedIntegers::QCheckedInt<int>;
 
    constexpr QMargins(Representation left,
                       Representation top,
                       Representation right,
                       Representation bottom) noexcept
        : m_left(left), m_top(top), m_right(right), m_bottom(bottom)
    {
    }
 
    Representation m_left;
    Representation m_top;
    Representation m_right;
    Representation m_bottom;
 
    friend constexpr bool comparesEqual(const QMargins &lhs, const QMargins &rhs) noexcept
    {
        return lhs.m_left == rhs.m_left
                && lhs.m_top == rhs.m_top
                && lhs.m_right == rhs.m_right
                && lhs.m_bottom == rhs.m_bottom;
    }
    Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QMargins)
 
    template <std::size_t I,
              typename M,
              std::enable_if_t<(I < 4), bool> = true,
              std::enable_if_t<std::is_same_v<q20::remove_cvref_t<M>, QMargins>, bool> = true>
    friend constexpr decltype(auto) get(M &&m) noexcept
    {
        if constexpr (I == 0)
            return q23::forward_like<M>(m.m_left).as_underlying();
        else if constexpr (I == 1)
            return q23::forward_like<M>(m.m_top).as_underlying();
        else if constexpr (I == 2)
            return q23::forward_like<M>(m.m_right).as_underlying();
        else if constexpr (I == 3)
            return q23::forward_like<M>(m.m_bottom).as_underlying();
    }
};
 
Q_DECLARE_TYPEINFO(QMargins, Q_RELOCATABLE_TYPE);
 
/*****************************************************************************
  QMargins stream functions
 *****************************************************************************/
#ifndef QT_NO_DATASTREAM
Q_CORE_EXPORT QDataStream &operator<<(QDataStream &, const QMargins &);
Q_CORE_EXPORT QDataStream &operator>>(QDataStream &, QMargins &);
#endif
 
/*****************************************************************************
  QMargins inline functions
 *****************************************************************************/
 
constexpr inline QMargins::QMargins() noexcept : m_left(0), m_top(0), m_right(0), m_bottom(0) {}
 
constexpr inline QMargins::QMargins(int aleft, int atop, int aright, int abottom) noexcept
    : m_left(aleft), m_top(atop), m_right(aright), m_bottom(abottom) {}
 
constexpr inline bool QMargins::isNull() const noexcept
{ return m_left==0 && m_top==0 && m_right==0 && m_bottom==0; }
 
constexpr inline int QMargins::left() const noexcept
{ return m_left.value(); }
 
constexpr inline int QMargins::top() const noexcept
{ return m_top.value(); }
 
constexpr inline int QMargins::right() const noexcept
{ return m_right.value(); }
 
constexpr inline int QMargins::bottom() const noexcept
{ return m_bottom.value(); }
 
 
constexpr inline void QMargins::setLeft(int aleft) noexcept
{ m_left.setValue(aleft); }
 
constexpr inline void QMargins::setTop(int atop) noexcept
{ m_top.setValue(atop); }
 
constexpr inline void QMargins::setRight(int aright) noexcept
{ m_right.setValue(aright); }
 
constexpr inline void QMargins::setBottom(int abottom) noexcept
{ m_bottom.setValue(abottom); }
 
constexpr inline QMargins operator+(const QMargins &m1, const QMargins &m2) noexcept
{
    return QMargins(m1.m_left + m2.m_left, m1.m_top + m2.m_top,
                    m1.m_right + m2.m_right, m1.m_bottom + m2.m_bottom);
}
 
constexpr inline QMargins operator-(const QMargins &m1, const QMargins &m2) noexcept
{
    return QMargins(m1.m_left - m2.m_left, m1.m_top - m2.m_top,
                    m1.m_right - m2.m_right, m1.m_bottom - m2.m_bottom);
}
 
constexpr inline QMargins operator+(const QMargins &lhs, int rhs) noexcept
{
    return QMargins(lhs.m_left + rhs, lhs.m_top + rhs,
                    lhs.m_right + rhs, lhs.m_bottom + rhs);
}
 
constexpr inline QMargins operator+(int lhs, const QMargins &rhs) noexcept
{
    return QMargins(rhs.m_left + lhs, rhs.m_top + lhs,
                    rhs.m_right + lhs, rhs.m_bottom + lhs);
}
 
constexpr inline QMargins operator-(const QMargins &lhs, int rhs) noexcept
{
    return QMargins(lhs.m_left - rhs, lhs.m_top - rhs,
                    lhs.m_right - rhs, lhs.m_bottom - rhs);
}
 
constexpr inline QMargins operator*(const QMargins &margins, int factor) noexcept
{
    return QMargins(margins.m_left * factor, margins.m_top * factor,
                    margins.m_right * factor, margins.m_bottom * factor);
}
 
constexpr inline QMargins operator*(int factor, const QMargins &margins) noexcept
{
    return QMargins(margins.m_left * factor, margins.m_top * factor,
                    margins.m_right * factor, margins.m_bottom * factor);
}
 
constexpr inline QMargins operator*(const QMargins &margins, qreal factor) noexcept
{
    // Deliberately using left(), top() etc. (checked ints don't have FP arithmetic)
    return QMargins(QtPrivate::qSaturateRound(margins.left() * factor),
                    QtPrivate::qSaturateRound(margins.top() * factor),
                    QtPrivate::qSaturateRound(margins.right() * factor),
                    QtPrivate::qSaturateRound(margins.bottom() * factor));
}
 
constexpr inline QMargins operator*(qreal factor, const QMargins &margins) noexcept
{
    return QMargins(QtPrivate::qSaturateRound(margins.left() * factor),
                    QtPrivate::qSaturateRound(margins.top() * factor),
                    QtPrivate::qSaturateRound(margins.right() * factor),
                    QtPrivate::qSaturateRound(margins.bottom() * factor));
}
 
constexpr inline QMargins operator/(const QMargins &margins, int divisor)
{
    return QMargins(margins.m_left / divisor, margins.m_top / divisor,
                    margins.m_right / divisor, margins.m_bottom / divisor);
}
 
constexpr inline QMargins operator/(const QMargins &margins, qreal divisor)
{
    Q_ASSERT(!qFuzzyIsNull(divisor));
    return QMargins(QtPrivate::qSaturateRound(margins.left() / divisor),
                    QtPrivate::qSaturateRound(margins.top() / divisor),
                    QtPrivate::qSaturateRound(margins.right() / divisor),
                    QtPrivate::qSaturateRound(margins.bottom() / divisor));
}
 
constexpr inline QMargins operator|(const QMargins &m1, const QMargins &m2) noexcept
{
    return QMargins(qMax(m1.m_left, m2.m_left), qMax(m1.m_top, m2.m_top),
                    qMax(m1.m_right, m2.m_right), qMax(m1.m_bottom, m2.m_bottom));
}
 
constexpr inline QMargins &QMargins::operator+=(const QMargins &margins) noexcept
{
    return *this = *this + margins;
}
 
constexpr inline QMargins &QMargins::operator-=(const QMargins &margins) noexcept
{
    return *this = *this - margins;
}
 
constexpr inline QMargins &QMargins::operator+=(int margin) noexcept
{
    m_left += margin;
    m_top += margin;
    m_right += margin;
    m_bottom += margin;
    return *this;
}
 
constexpr inline QMargins &QMargins::operator-=(int margin) noexcept
{
    m_left -= margin;
    m_top -= margin;
    m_right -= margin;
    m_bottom -= margin;
    return *this;
}
 
constexpr inline QMargins &QMargins::operator*=(int factor) noexcept
{
    return *this = *this * factor;
}
 
constexpr inline QMargins &QMargins::operator/=(int divisor)
{
    return *this = *this / divisor;
}
 
constexpr inline QMargins &QMargins::operator*=(qreal factor) noexcept
{
    return *this = *this * factor;
}
 
constexpr inline QMargins &QMargins::operator/=(qreal divisor)
{
    return *this = *this / divisor;
}
 
constexpr inline QMargins operator+(const QMargins &margins) noexcept
{
    return margins;
}
 
constexpr inline QMargins operator-(const QMargins &margins) noexcept
{
    return QMargins(-margins.left(), -margins.top(), -margins.right(), -margins.bottom());
}
 
#ifndef QT_NO_DEBUG_STREAM
Q_CORE_EXPORT QDebug operator<<(QDebug, const QMargins &);
#endif
 
/*****************************************************************************
  QMarginsF class
 *****************************************************************************/
 
class QMarginsF
{
public:
    constexpr QMarginsF() noexcept;
    constexpr QMarginsF(qreal left, qreal top, qreal right, qreal bottom) noexcept;
    constexpr QMarginsF(const QMargins &margins) noexcept;
 
    constexpr bool isNull() const noexcept;
 
    constexpr qreal left() const noexcept;
    constexpr qreal top() const noexcept;
    constexpr qreal right() const noexcept;
    constexpr qreal bottom() const noexcept;
 
    constexpr void setLeft(qreal aleft) noexcept;
    constexpr void setTop(qreal atop) noexcept;
    constexpr void setRight(qreal aright) noexcept;
    constexpr void setBottom(qreal abottom) noexcept;
 
    constexpr QMarginsF &operator+=(const QMarginsF &margins) noexcept;
    constexpr QMarginsF &operator-=(const QMarginsF &margins) noexcept;
    constexpr QMarginsF &operator+=(qreal addend) noexcept;
    constexpr QMarginsF &operator-=(qreal subtrahend) noexcept;
    constexpr QMarginsF &operator*=(qreal factor) noexcept;
    constexpr QMarginsF &operator/=(qreal divisor);
 
    constexpr inline QMargins toMargins() const noexcept;
 
private:
    qreal m_left;
    qreal m_top;
    qreal m_right;
    qreal m_bottom;
 
    QT_WARNING_PUSH
    QT_WARNING_DISABLE_FLOAT_COMPARE
    friend constexpr bool qFuzzyCompare(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
    {
        return ((!lhs.m_left || !rhs.m_left) ? qFuzzyIsNull(lhs.m_left - rhs.m_left)
                                             : qFuzzyCompare(lhs.m_left, rhs.m_left))
                && ((!lhs.m_top || !rhs.m_top) ? qFuzzyIsNull(lhs.m_top - rhs.m_top)
                                               : qFuzzyCompare(lhs.m_top, rhs.m_top))
                && ((!lhs.m_right || !rhs.m_right) ? qFuzzyIsNull(lhs.m_right - rhs.m_right)
                                                   : qFuzzyCompare(lhs.m_right, rhs.m_right))
                && ((!lhs.m_bottom || !rhs.m_bottom) ? qFuzzyIsNull(lhs.m_bottom - rhs.m_bottom)
                                                     : qFuzzyCompare(lhs.m_bottom, rhs.m_bottom));
    }
    QT_WARNING_POP
    friend constexpr bool qFuzzyIsNull(const QMarginsF &m) noexcept
    {
        return qFuzzyIsNull(m.m_left) && qFuzzyIsNull(m.m_top)
                && qFuzzyIsNull(m.m_right) && qFuzzyIsNull(m.m_bottom);
    }
 
    friend constexpr bool comparesEqual(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
    {
        return qFuzzyCompare(lhs, rhs);
    }
    Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QMarginsF)
 
    friend constexpr bool comparesEqual(const QMarginsF &lhs, const QMargins &rhs) noexcept
    { return comparesEqual(lhs, rhs.toMarginsF()); }
    Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QMarginsF, QMargins)
 
    template <std::size_t I,
              typename M,
              std::enable_if_t<(I < 4), bool> = true,
              std::enable_if_t<std::is_same_v<q20::remove_cvref_t<M>, QMarginsF>, bool> = true>
    friend constexpr decltype(auto) get(M &&m) noexcept
    {
        if constexpr (I == 0)
            return q23::forward_like<M>(m.m_left);
        else if constexpr (I == 1)
            return q23::forward_like<M>(m.m_top);
        else if constexpr (I == 2)
            return q23::forward_like<M>(m.m_right);
        else if constexpr (I == 3)
            return q23::forward_like<M>(m.m_bottom);
    }
};
 
Q_DECLARE_TYPEINFO(QMarginsF, Q_RELOCATABLE_TYPE);
 
/*****************************************************************************
  QMarginsF stream functions
 *****************************************************************************/
 
#ifndef QT_NO_DATASTREAM
Q_CORE_EXPORT QDataStream &operator<<(QDataStream &, const QMarginsF &);
Q_CORE_EXPORT QDataStream &operator>>(QDataStream &, QMarginsF &);
#endif
 
/*****************************************************************************
  QMarginsF inline functions
 *****************************************************************************/
 
constexpr inline QMarginsF::QMarginsF() noexcept
    : m_left(0), m_top(0), m_right(0), m_bottom(0) {}
 
constexpr inline QMarginsF::QMarginsF(qreal aleft, qreal atop, qreal aright, qreal abottom) noexcept
    : m_left(aleft), m_top(atop), m_right(aright), m_bottom(abottom) {}
 
constexpr inline QMarginsF::QMarginsF(const QMargins &margins) noexcept
    : m_left(margins.left()), m_top(margins.top()), m_right(margins.right()), m_bottom(margins.bottom()) {}
 
constexpr inline bool QMarginsF::isNull() const noexcept
{ return qFuzzyIsNull(m_left) && qFuzzyIsNull(m_top) && qFuzzyIsNull(m_right) && qFuzzyIsNull(m_bottom); }
 
constexpr inline qreal QMarginsF::left() const noexcept
{ return m_left; }
 
constexpr inline qreal QMarginsF::top() const noexcept
{ return m_top; }
 
constexpr inline qreal QMarginsF::right() const noexcept
{ return m_right; }
 
constexpr inline qreal QMarginsF::bottom() const noexcept
{ return m_bottom; }
 
 
constexpr inline void QMarginsF::setLeft(qreal aleft) noexcept
{ m_left = aleft; }
 
constexpr inline void QMarginsF::setTop(qreal atop) noexcept
{ m_top = atop; }
 
constexpr inline void QMarginsF::setRight(qreal aright) noexcept
{ m_right = aright; }
 
constexpr inline void QMarginsF::setBottom(qreal abottom) noexcept
{ m_bottom = abottom; }
 
constexpr inline QMarginsF operator+(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
{
    return QMarginsF(lhs.left() + rhs.left(), lhs.top() + rhs.top(),
                     lhs.right() + rhs.right(), lhs.bottom() + rhs.bottom());
}
 
constexpr inline QMarginsF operator-(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
{
    return QMarginsF(lhs.left() - rhs.left(), lhs.top() - rhs.top(),
                     lhs.right() - rhs.right(), lhs.bottom() - rhs.bottom());
}
 
constexpr inline QMarginsF operator+(const QMarginsF &lhs, qreal rhs) noexcept
{
    return QMarginsF(lhs.left() + rhs, lhs.top() + rhs,
                     lhs.right() + rhs, lhs.bottom() + rhs);
}
 
constexpr inline QMarginsF operator+(qreal lhs, const QMarginsF &rhs) noexcept
{
    return QMarginsF(rhs.left() + lhs, rhs.top() + lhs,
                     rhs.right() + lhs, rhs.bottom() + lhs);
}
 
constexpr inline QMarginsF operator-(const QMarginsF &lhs, qreal rhs) noexcept
{
    return QMarginsF(lhs.left() - rhs, lhs.top() - rhs,
                     lhs.right() - rhs, lhs.bottom() - rhs);
}
 
constexpr inline QMarginsF operator*(const QMarginsF &lhs, qreal rhs) noexcept
{
    return QMarginsF(lhs.left() * rhs, lhs.top() * rhs,
                     lhs.right() * rhs, lhs.bottom() * rhs);
}
 
constexpr inline QMarginsF operator*(qreal lhs, const QMarginsF &rhs) noexcept
{
    return QMarginsF(rhs.left() * lhs, rhs.top() * lhs,
                     rhs.right() * lhs, rhs.bottom() * lhs);
}
 
constexpr inline QMarginsF operator/(const QMarginsF &lhs, qreal divisor)
{
    Q_ASSERT(divisor < 0 || divisor > 0);
    return QMarginsF(lhs.left() / divisor, lhs.top() / divisor,
                     lhs.right() / divisor, lhs.bottom() / divisor);
}
 
constexpr inline QMarginsF operator|(const QMarginsF &m1, const QMarginsF &m2) noexcept
{
    return QMarginsF(qMax(m1.left(), m2.left()), qMax(m1.top(), m2.top()),
                     qMax(m1.right(), m2.right()), qMax(m1.bottom(), m2.bottom()));
}
 
constexpr inline QMarginsF &QMarginsF::operator+=(const QMarginsF &margins) noexcept
{
    return *this = *this + margins;
}
 
constexpr inline QMarginsF &QMarginsF::operator-=(const QMarginsF &margins) noexcept
{
    return *this = *this - margins;
}
 
constexpr inline QMarginsF &QMarginsF::operator+=(qreal addend) noexcept
{
    m_left += addend;
    m_top += addend;
    m_right += addend;
    m_bottom += addend;
    return *this;
}
 
constexpr inline QMarginsF &QMarginsF::operator-=(qreal subtrahend) noexcept
{
    m_left -= subtrahend;
    m_top -= subtrahend;
    m_right -= subtrahend;
    m_bottom -= subtrahend;
    return *this;
}
 
constexpr inline QMarginsF &QMarginsF::operator*=(qreal factor) noexcept
{
    return *this = *this * factor;
}
 
constexpr inline QMarginsF &QMarginsF::operator/=(qreal divisor)
{
    return *this = *this / divisor;
}
 
constexpr inline QMarginsF operator+(const QMarginsF &margins) noexcept
{
    return margins;
}
 
constexpr inline QMarginsF operator-(const QMarginsF &margins) noexcept
{
    return QMarginsF(-margins.left(), -margins.top(), -margins.right(), -margins.bottom());
}
 
constexpr QMarginsF QMargins::toMarginsF() const noexcept { return *this; }
 
constexpr inline QMargins QMarginsF::toMargins() const noexcept
{
    return QMargins(QtPrivate::qSaturateRound(m_left),
                    QtPrivate::qSaturateRound(m_top),
                    QtPrivate::qSaturateRound(m_right),
                    QtPrivate::qSaturateRound(m_bottom));
}
 
#ifndef QT_NO_DEBUG_STREAM
Q_CORE_EXPORT QDebug operator<<(QDebug, const QMarginsF &);
#endif
 
QT_END_NAMESPACE
 
/*****************************************************************************
  QMargins/QMarginsF tuple protocol
 *****************************************************************************/
 
namespace std {
    template <>
    class tuple_size<QT_PREPEND_NAMESPACE(QMargins)> : public integral_constant<size_t, 4> {};
    template <>
    class tuple_element<0, QT_PREPEND_NAMESPACE(QMargins)> { public: using type = int; };
    template <>
    class tuple_element<1, QT_PREPEND_NAMESPACE(QMargins)> { public: using type = int; };
    template <>
    class tuple_element<2, QT_PREPEND_NAMESPACE(QMargins)> { public: using type = int; };
    template <>
    class tuple_element<3, QT_PREPEND_NAMESPACE(QMargins)> { public: using type = int; };
 
    template <>
    class tuple_size<QT_PREPEND_NAMESPACE(QMarginsF)> : public integral_constant<size_t, 4> {};
    template <>
    class tuple_element<0, QT_PREPEND_NAMESPACE(QMarginsF)> { public: using type = QT_PREPEND_NAMESPACE(qreal); };
    template <>
    class tuple_element<1, QT_PREPEND_NAMESPACE(QMarginsF)> { public: using type = QT_PREPEND_NAMESPACE(qreal); };
    template <>
    class tuple_element<2, QT_PREPEND_NAMESPACE(QMarginsF)> { public: using type = QT_PREPEND_NAMESPACE(qreal); };
    template <>
    class tuple_element<3, QT_PREPEND_NAMESPACE(QMarginsF)> { public: using type = QT_PREPEND_NAMESPACE(qreal); };
}
 
#endif // QMARGINS_H