Qt Reference Documentation

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QVector4D Class Reference

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

 #include <QVector4D>

This class was introduced in Qt 4.6.

Public Functions

QVector4D ()
QVector4D ( qreal xpos, qreal ypos, qreal zpos, qreal wpos )
QVector4D ( const QPoint & point )
QVector4D ( const QPointF & point )
QVector4D ( const QVector2D & vector )
QVector4D ( const QVector2D & vector, qreal zpos, qreal wpos )
QVector4D ( const QVector3D & vector )
QVector4D ( const QVector3D & vector, qreal wpos )
bool isNull () const
qreal length () const
qreal lengthSquared () const
void normalize ()
QVector4D normalized () const
void setW ( qreal w )
void setX ( qreal x )
void setY ( qreal y )
void setZ ( qreal z )
QPoint toPoint () const
QPointF toPointF () const
QVector2D toVector2D () const
QVector2D toVector2DAffine () const
QVector3D toVector3D () const
QVector3D toVector3DAffine () const
qreal w () const
qreal x () const
qreal y () const
qreal z () const
operator QVariant () const
QVector4D & operator*= ( qreal factor )
QVector4D & operator*= ( const QVector4D & vector )
QVector4D & operator+= ( const QVector4D & vector )
QVector4D & operator-= ( const QVector4D & vector )
QVector4D & operator/= ( qreal divisor )

Static Public Members

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

Related Non-Members

bool qFuzzyCompare ( const QVector4D & v1, const QVector4D & v2 )
bool operator!= ( const QVector4D & v1, const QVector4D & v2 )
const QVector4D operator* ( qreal factor, const QVector4D & vector )
const QVector4D operator* ( const QVector4D & vector, qreal factor )
const QVector4D operator* ( const QVector4D & v1, const QVector4D & v2 )
const QVector4D operator+ ( const QVector4D & v1, const QVector4D & v2 )
const QVector4D operator- ( const QVector4D & v1, const QVector4D & v2 )
const QVector4D operator- ( const QVector4D & vector )
const QVector4D operator/ ( const QVector4D & vector, qreal divisor )
QDataStream & operator<< ( QDataStream & stream, const QVector4D & vector )
bool operator== ( const QVector4D & v1, const QVector4D & v2 )
QDataStream & operator>> ( QDataStream & stream, QVector4D & vector )

Detailed Description

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

The QVector4D class can also be used to represent vertices in 4D space. We therefore do not need to provide a separate vertex class.

Note: By design values in the QVector4D instance are stored as float. This means that on platforms where the qreal arguments to QVector4D functions are represented by double values, it is possible to lose precision.

See also QQuaternion, QVector2D, and QVector3D.

Member Function Documentation

QVector4D::QVector4D ()

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

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

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

QVector4D::QVector4D ( const QPoint & point )

Constructs a vector with x and y coordinates from a 2D point, and z and w coordinates of 0.

QVector4D::QVector4D ( const QPointF & point )

Constructs a vector with x and y coordinates from a 2D point, and z and w coordinates of 0.

QVector4D::QVector4D ( const QVector2D & vector )

Constructs a 4D vector from the specified 2D vector. The z and w coordinates are set to zero.

See also toVector2D().

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

Constructs a 4D vector from the specified 2D vector. The z and w coordinates are set to zpos and wpos respectively.

See also toVector2D().

QVector4D::QVector4D ( const QVector3D & vector )

Constructs a 4D vector from the specified 3D vector. The w coordinate is set to zero.

See also toVector3D().

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

Constructs a 4D vector from the specified 3D vector. The w coordinate is set to wpos.

See also toVector3D().

qreal QVector4D::dotProduct ( const QVector4D & v1, const QVector4D & v2 ) [static]

Returns the dot product of v1 and v2.

bool QVector4D::isNull () const

Returns true if the x, y, z, and w coordinates are set to 0.0, otherwise returns false.

qreal QVector4D::length () const

Returns the length of the vector from the origin.

See also lengthSquared() and normalized().

qreal QVector4D::lengthSquared () const

Returns the squared length of the vector from the origin. This is equivalent to the dot product of the vector with itself.

See also length() and dotProduct().

void QVector4D::normalize ()

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.

See also length() and normalized().

QVector4D QVector4D::normalized () const

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.

See also length() and normalize().

void QVector4D::setW ( qreal w )

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

See also w(), setX(), setY(), and setZ().

void QVector4D::setX ( qreal x )

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

See also x(), setY(), setZ(), and setW().

void QVector4D::setY ( qreal y )

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

See also y(), setX(), setZ(), and setW().

void QVector4D::setZ ( qreal z )

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

See also z(), setX(), setY(), and setW().

QPoint QVector4D::toPoint () const

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

See also toPointF() and toVector2D().

QPointF QVector4D::toPointF () const

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

See also toPoint() and toVector2D().

QVector2D QVector4D::toVector2D () const

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

See also toVector2DAffine(), toVector3D(), and toPoint().

QVector2D QVector4D::toVector2DAffine () const

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.

See also toVector2D(), toVector3DAffine(), and toPoint().

QVector3D QVector4D::toVector3D () const

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

See also toVector3DAffine(), toVector2D(), and toPoint().

QVector3D QVector4D::toVector3DAffine () const

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.

See also toVector3D(), toVector2DAffine(), and toPoint().

qreal QVector4D::w () const

Returns the w coordinate of this point.

See also setW(), x(), y(), and z().

qreal QVector4D::x () const

Returns the x coordinate of this point.

See also setX(), y(), z(), and w().

qreal QVector4D::y () const

Returns the y coordinate of this point.

See also setY(), x(), z(), and w().

qreal QVector4D::z () const

Returns the z coordinate of this point.

See also setZ(), x(), y(), and w().

QVector4D::operator QVariant () const

Returns the 4D vector as a QVariant.

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

Multiplies this vector's coordinates by the given factor, and returns a reference to this vector.

See also operator/=().

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

Multiplies the components of this vector by the corresponding components in vector.

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

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

See also operator-=().

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

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

See also operator+=().

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

Divides this vector's coordinates by the given divisor, and returns a reference to this vector.

See also operator*=().

Related Non-Members

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

Returns true if v1 and v2 are equal, allowing for a small fuzziness factor for floating-point comparisons; false otherwise.

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

Returns true if v1 is not equal to v2; otherwise returns false. This operator uses an exact floating-point comparison.

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

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

See also QVector4D::operator*=().

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

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

See also QVector4D::operator*=().

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

Returns the vector consisting of the multiplication of the components from v1 and v2.

See also QVector4D::operator*=().

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

Returns a QVector4D object that is the sum of the given vectors, v1 and v2; each component is added separately.

See also QVector4D::operator+=().

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

Returns a QVector4D object that is formed by subtracting v2 from v1; each component is subtracted separately.

See also QVector4D::operator-=().

const QVector4D operator- ( const QVector4D & vector )

This is an overloaded function.

Returns a QVector4D object that is formed by changing the sign of all three components of the given vector.

Equivalent to QVector4D(0,0,0,0) - vector.

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

Returns the QVector4D object formed by dividing all four components of the given vector by the given divisor.

See also QVector4D::operator/=().

QDataStream & operator<< ( QDataStream & stream, const QVector4D & vector )

Writes the given vector to the given stream and returns a reference to the stream.

See also Serializing Qt Data Types.

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

Returns true if v1 is equal to v2; otherwise returns false. This operator uses an exact floating-point comparison.

QDataStream & operator>> ( QDataStream & stream, QVector4D & vector )

Reads a 4D vector from the given stream into the given vector and returns a reference to the stream.

See also Serializing Qt Data Types.