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#include "qvector4d.h"

#include "qvector3d.h"

#include "qvector2d.h"

#include <QtCore/qdebug.h>

#include <QtCore/qvariant.h>

#include <QtCore/qmath.h>

QT_BEGIN_NAMESPACE

#ifndef QT_NO_VECTOR4D

/*!

    \class QVector4D

    \brief The QVector4D class represents a vector or vertex in 4D space.

    \since 4.6

    \ingroup painting-3D

    The QVector4D class can also be used to represent vertices in 4D space.

    We therefore do not need to provide a separate vertex class.

    \sa QQuaternion, QVector2D, QVector3D

*/

/*!

    \fn QVector4D::QVector4D()

    Constructs a null vector, i.e. with coordinates (0, 0, 0, 0).

*/

/*!

    \fn QVector4D::QVector4D(qreal xpos, qreal ypos, qreal zpos, qreal wpos)

    Constructs a vector with coordinates (\a xpos, \a ypos, \a zpos, \a wpos).

*/

/*!

    \fn QVector4D::QVector4D(const QPoint& point)

    Constructs a vector with x and y coordinates from a 2D \a point, and

    z and w coordinates of 0.

*/

/*!

    \fn QVector4D::QVector4D(const QPointF& point)

    Constructs a vector with x and y coordinates from a 2D \a point, and

    z and w coordinates of 0.

*/

#ifndef QT_NO_VECTOR2D

/*!

    Constructs a 4D vector from the specified 2D \a vector.  The z

    and w coordinates are set to zero.

    \sa toVector2D()

*/

QVector4D::QVector4D(const QVector2D& vector)

{

    xp = vector.xp;

    yp = vector.yp;

    zp = 0.0f;

    wp = 0.0f;

}

/*!

    Constructs a 4D vector from the specified 2D \a vector.  The z

    and w coordinates are set to \a zpos and \a wpos respectively.

    \sa toVector2D()

*/

QVector4D::QVector4D(const QVector2D& vector, qreal zpos, qreal wpos)

{

    xp = vector.xp;

    yp = vector.yp;

    zp = zpos;

    wp = wpos;

}

#endif

#ifndef QT_NO_VECTOR3D

/*!

    Constructs a 4D vector from the specified 3D \a vector.  The w

    coordinate is set to zero.

    \sa toVector3D()

*/

QVector4D::QVector4D(const QVector3D& vector)

{

    xp = vector.xp;

    yp = vector.yp;

    zp = vector.zp;

    wp = 0.0f;

}

/*!

    Constructs a 4D vector from the specified 3D \a vector.  The w

    coordinate is set to \a wpos.

    \sa toVector3D()

*/

QVector4D::QVector4D(const QVector3D& vector, qreal wpos)

{

    xp = vector.xp;

    yp = vector.yp;

    zp = vector.zp;

    wp = wpos;

}

#endif

/*!

    \fn bool QVector4D::isNull() const

    Returns true if the x, y, z, and w coordinates are set to 0.0,

    otherwise returns false.

*/

/*!

    \fn qreal QVector4D::x() const

    Returns the x coordinate of this point.

    \sa setX(), y(), z(), w()

*/

/*!

    \fn qreal QVector4D::y() const

    Returns the y coordinate of this point.

    \sa setY(), x(), z(), w()

*/

/*!

    \fn qreal QVector4D::z() const

    Returns the z coordinate of this point.

    \sa setZ(), x(), y(), w()

*/

/*!

    \fn qreal QVector4D::w() const

    Returns the w coordinate of this point.

    \sa setW(), x(), y(), z()

*/

/*!

    \fn void QVector4D::setX(qreal x)

    Sets the x coordinate of this point to the given \a x coordinate.

    \sa x(), setY(), setZ(), setW()

*/

/*!

    \fn void QVector4D::setY(qreal y)

    Sets the y coordinate of this point to the given \a y coordinate.

    \sa y(), setX(), setZ(), setW()

*/

/*!

    \fn void QVector4D::setZ(qreal z)

    Sets the z coordinate of this point to the given \a z coordinate.

    \sa z(), setX(), setY(), setW()

*/

/*!

    \fn void QVector4D::setW(qreal w)

    Sets the w coordinate of this point to the given \a w coordinate.

    \sa w(), setX(), setY(), setZ()

*/

/*!

    Returns the length of the vector from the origin.

    \sa lengthSquared(), normalized()

*/

qreal QVector4D::length() const

{

    return qSqrt(xp * xp + yp * yp + zp * zp + wp * wp);

}

/*!

    Returns the squared length of the vector from the origin.

    This is equivalent to the dot product of the vector with itself.

    \sa length(), dotProduct()

*/

qreal QVector4D::lengthSquared() const

{

    return xp * xp + yp * yp + zp * zp + wp * wp;

}

/*!

    Returns the normalized unit vector form of this vector.

    If this vector is null, then a null vector is returned.  If the length

    of the vector is very close to 1, then the vector will be returned as-is.

    Otherwise the normalized form of the vector of length 1 will be returned.

    \sa length(), normalize()

*/

QVector4D QVector4D::normalized() const

{

    // Need some extra precision if the length is very small.

    double len = double(xp) * double(xp) +

                 double(yp) * double(yp) +

                 double(zp) * double(zp) +

                 double(wp) * double(wp);

    if (qFuzzyIsNull(len - 1.0f))

        return *this;

    else if (!qFuzzyIsNull(len))

        return *this / qSqrt(len);

    else

        return QVector4D();

}

/*!

    Normalizes the currect vector in place.  Nothing happens if this

    vector is a null vector or the length of the vector is very close to 1.

    \sa length(), normalized()

*/

void QVector4D::normalize()

{

    // Need some extra precision if the length is very small.

    double len = double(xp) * double(xp) +

                 double(yp) * double(yp) +

                 double(zp) * double(zp) +

                 double(wp) * double(wp);

    if (qFuzzyIsNull(len - 1.0f) || qFuzzyIsNull(len))

        return;

    len = qSqrt(len);

    xp /= len;

    yp /= len;

    zp /= len;

    wp /= len;

}

/*!

    \fn QVector4D &QVector4D::operator+=(const QVector4D &vector)

    Adds the given \a vector to this vector and returns a reference to

    this vector.

    \sa operator-=()

*/

/*!

    \fn QVector4D &QVector4D::operator-=(const QVector4D &vector)

    Subtracts the given \a vector from this vector and returns a reference to

    this vector.

    \sa operator+=()

*/

/*!

    \fn QVector4D &QVector4D::operator*=(qreal factor)

    Multiplies this vector's coordinates by the given \a factor, and

    returns a reference to this vector.

    \sa operator/=()

*/

/*!

    \fn QVector4D &QVector4D::operator*=(const QVector4D &vector)

    Multiplies the components of this vector by the corresponding

    components in \a vector.

*/

/*!

    \fn QVector4D &QVector4D::operator/=(qreal divisor)

    Divides this vector's coordinates by the given \a divisor, and

    returns a reference to this vector.

    \sa operator*=()

*/

/*!

    Returns the dot product of \a v1 and \a v2.

*/

qreal QVector4D::dotProduct(const QVector4D& v1, const QVector4D& v2)

{

    return v1.xp * v2.xp + v1.yp * v2.yp + v1.zp * v2.zp + v1.wp * v2.wp;

}

/*!

    \fn bool operator==(const QVector4D &v1, const QVector4D &v2)

    \relates QVector4D

    Returns true if \a v1 is equal to \a v2; otherwise returns false.

    This operator uses an exact floating-point comparison.

*/

/*!

    \fn bool operator!=(const QVector4D &v1, const QVector4D &v2)

    \relates QVector4D

    Returns true if \a v1 is not equal to \a v2; otherwise returns false.

    This operator uses an exact floating-point comparison.

*/

/*!

    \fn const QVector4D operator+(const QVector4D &v1, const QVector4D &v2)

    \relates QVector4D

    Returns a QVector4D object that is the sum of the given vectors, \a v1

    and \a v2; each component is added separately.

    \sa QVector4D::operator+=()

*/

/*!

    \fn const QVector4D operator-(const QVector4D &v1, const QVector4D &v2)

    \relates QVector4D

    Returns a QVector4D object that is formed by subtracting \a v2 from \a v1;

    each component is subtracted separately.

    \sa QVector4D::operator-=()

*/

/*!

    \fn const QVector4D operator*(qreal factor, const QVector4D &vector)

    \relates QVector4D

    Returns a copy of the given \a vector,  multiplied by the given \a factor.

    \sa QVector4D::operator*=()

*/

/*!

    \fn const QVector4D operator*(const QVector4D &vector, qreal factor)

    \relates QVector4D

    Returns a copy of the given \a vector,  multiplied by the given \a factor.

    \sa QVector4D::operator*=()

*/

/*!

    \fn const QVector4D operator*(const QVector4D &v1, const QVector4D& v2)

    \relates QVector4D

    Returns the vector consisting of the multiplication of the

    components from \a v1 and \a v2.

    \sa QVector4D::operator*=()

*/

/*!

    \fn const QVector4D operator-(const QVector4D &vector)

    \relates QVector4D

    \overload

    Returns a QVector4D object that is formed by changing the sign of

    all three components of the given \a vector.

    Equivalent to \c {QVector4D(0,0,0,0) - vector}.

*/

/*!

    \fn const QVector4D operator/(const QVector4D &vector, qreal divisor)

    \relates QVector4D

    Returns the QVector4D object formed by dividing all four components of

    the given \a vector by the given \a divisor.

    \sa QVector4D::operator/=()

*/

/*!

    \fn bool qFuzzyCompare(const QVector4D& v1, const QVector4D& v2)

    \relates QVector4D

    Returns true if \a v1 and \a v2 are equal, allowing for a small

    fuzziness factor for floating-point comparisons; false otherwise.

*/

#ifndef QT_NO_VECTOR2D

/*!

    Returns the 2D vector form of this 4D vector, dropping the z and w coordinates.

    \sa toVector2DAffine(), toVector3D(), toPoint()

*/

QVector2D QVector4D::toVector2D() const

{

    return QVector2D(xp, yp, 1);

}

/*!

    Returns the 2D vector form of this 4D vector, dividing the x and y

    coordinates by the w coordinate and dropping the z coordinate.

    Returns a null vector if w is zero.

    \sa toVector2D(), toVector3DAffine(), toPoint()

*/

QVector2D QVector4D::toVector2DAffine() const

{

    if (qIsNull(wp))

        return QVector2D();

    return QVector2D(xp / wp, yp / wp, 1);

}

#endif

#ifndef QT_NO_VECTOR3D

/*!

    Returns the 3D vector form of this 4D vector, dropping the w coordinate.

    \sa toVector3DAffine(), toVector2D(), toPoint()

*/

QVector3D QVector4D::toVector3D() const

{

    return QVector3D(xp, yp, zp, 1);

}

/*!

    Returns the 3D vector form of this 4D vector, dividing the x, y, and

    z coordinates by the w coordinate.  Returns a null vector if w is zero.

    \sa toVector3D(), toVector2DAffine(), toPoint()

*/

QVector3D QVector4D::toVector3DAffine() const

{

    if (qIsNull(wp))

        return QVector3D();

    return QVector3D(xp / wp, yp / wp, zp / wp, 1);

}

#endif

/*!

    \fn QPoint QVector4D::toPoint() const

    Returns the QPoint form of this 4D vector. The z and w coordinates

    are dropped.

    \sa toPointF(), toVector2D()

*/

/*!

    \fn QPointF QVector4D::toPointF() const

    Returns the QPointF form of this 4D vector. The z and w coordinates

    are dropped.

    \sa toPoint(), toVector2D()

*/

/*!

    Returns the 4D vector as a QVariant.

*/

QVector4D::operator QVariant() const

{

    return QVariant(QVariant::Vector4D, this);

}

#ifndef QT_NO_DEBUG_STREAM

QDebug operator<<(QDebug dbg, const QVector4D &vector)

{

    dbg.nospace() << "QVector4D("

        << vector.x() << ", " << vector.y() << ", "

        << vector.z() << ", " << vector.w() << ')';

    return dbg.space();

}