The QPointF class defines a point in the plane using floating point precision. More...

Public Methods
	QPointF ()

	QPointF (const QPoint &point)

	QPointF (qreal xPos, qreal yPos)

bool	isNull () const

qreal	manhattanLength () const

QPointF &	operator*= (qreal factor)

QPointF &	operator+= (const QPointF &point)

QPointF &	operator-= (const QPointF &point)

QPointF &	operator/= (qreal factor)

qreal &	rx ()

qreal &	ry ()

void	setX (qreal xPos)

void	setY (qreal yPos)

QPoint	toPoint () const

qreal	x () const

qreal	y () const

Friends
bool	operator!= (const QPointF &point1, const QPointF &point2)

const QPointF	operator* (const QPointF &point, qreal factor)

const QPointF	operator* (qreal factor, const QPointF &point)

const QPointF	operator+ (const QPointF &point1, const QPointF &point2)

const QPointF	operator- (const QPointF &point)

const QPointF	operator- (const QPointF &point1, const QPointF &point2)

const QPointF	operator/ (const QPointF &point, qreal factor)

bool	operator== (const QPointF &point1, const QPointF &point2)

class	QMatrix

class	QTransform

Related Functions
These are not member functions
QDataStream &	operator<< (QDataStream &stream, const QPointF &pointF)

QDataStream &	operator>> (QDataStream &stream, QPointF &pointF)

Detailed Description

The QPointF class defines a point in the plane using floating point precision.

A point is specified by a x coordinate and an y coordinate which can be accessed using the x() and y() functions. The coordinates of the point are specified using floating point numbers for accuracy. The isNull() function returns true if both x and y are set to 0.0. The coordinates can be set (or altered) using the setX() and setY() functions, or alternatively the rx() and ry() functions which return references to the coordinates (allowing direct manipulation).

Given a point p, the following statements are all equivalent.

QPointF p;
 
p.setX(p.x() + 1.0);
p += QPointF(1.0, 0.0);
p.rx()++;

A QPointF object can also be used as a vector: Addition and subtraction are defined as for vectors (each component is added separately). A QPointF object can also be divided or multiplied by an int or a qreal.

In addition, the QPointF class provides a constructor converting a QPoint object into a QPointF object, and a corresponding toPoint() function which returns a QPoint copy of this point. Finally, QPointF objects can be streamed as well as compared.

See also: QPoint, QPolygonF

Constructor & Destructor Documentation

QPointF::QPointF ( )

inline

Constructs a null point, i.e. with coordinates (0.0, 0.0)

See also: isNull()

QPointF::QPointF ( const QPoint & point )

inline

Constructs a copy of the given point.

See also: toPoint()

QPointF::QPointF	(	qreal	xPos,
		qreal	yPos
	)

inline

Constructs a point with the given coordinates (xPos, yPos).

See also: setX(), setY()

Method Documentation

bool QPointF::isNull ( ) const

inline

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

Since this method treats +0.0 and -0.0 differently, points with zero-valued coordinates where either or both values have a negative sign are not defined to be null points.

qreal QPointF::manhattanLength ( ) const

Returns the sum of the absolute values of x() and y(), traditionally known as the "Manhattan length" of the vector from the origin to the point.

See also: QPoint::manhattanLength()

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

inline

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

QPointF p(-1.1, 4.1);

p *= 2.5; // p becomes (-2.75, 10.25)

See also: operator/=()

QPointF & QPointF::operator+= ( const QPointF & point )

inline

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

QPointF p( 3.1, 7.1);
QPointF q(-1.0, 4.1);
p += q;                             // p becomes (2.1, 11.2)

See also: operator-=()

QPointF & QPointF::operator-= ( const QPointF & point )

inline

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

QPointF p( 3.1, 7.1);
QPointF q(-1.0, 4.1);
p -= q;                             // p becomes (4.1, 3.0)

See also: operator+=()

QPointF & QPointF::operator/= ( qreal factor )

inline

Divides both x and y by the given factor, and returns a reference to this point.

QPointF p(-2.75, 10.25);

p /= 2.5; // p becomes (-1.1, 4.1)

See also: operator*=()

qreal & QPointF::rx ( )

inline

Returns a reference to the x coordinate of this point. Using a reference makes it possible to directly modify x.

QPointF p(1.1, 2.5);

--(p.rx()); // p becomes (0.1, 2.5)

See also: x(), setX()

qreal & QPointF::ry ( )

inline

Returns a reference to the y coordinate of this point. Using a reference makes it possible to directly modify y.

QPointF p(1.1, 2.5);

++(p.ry()); // p becomes (1.1, 3.5)

See also: y(), setY()

void QPointF::setX ( qreal xPos )

inline

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

See also: x(), setY()

void QPointF::setY ( qreal yPos )

inline

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

See also: y(), setX()

QPoint QPointF::toPoint ( ) const

inline

Rounds the coordinates of this point to the nearest integer, and returns a QPoint object with the rounded coordinates.

See also: QPointF()

qreal QPointF::x ( ) const

inline

Returns the x-coordinate of this point.

See also: setX(), rx()

qreal QPointF::y ( ) const

inline

Returns the y-coordinate of this point.

See also: setY(), ry()

Friends And Related Function Documentation

bool operator!=	(	const QPointF &	point1,
		const QPointF &	point2
	)

friend

Returns true if point1 is not equal to point2, otherwise returns false.

const QPointF operator*	(	const QPointF &	point,
		qreal	factor
	)

friend

Returns a copy of the given point multiplied by the given factor.

See also: QPointF::operator*=()

const QPointF operator*	(	qreal	factor,
		const QPointF &	point
	)

friend

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

const QPointF operator+	(	const QPointF &	point1,
		const QPointF &	point2
	)

friend

Returns a QPointF object that is the sum of the given points, point1 and point2, each component is added separately.

See also: QPointF::operator+=()

const QPointF operator- ( const QPointF & point )

friend

Returns a QPointF object that is formed by changing the sign of both components of the given point.

Equivalent to QPointF(0,0) - point.

const QPointF operator-	(	const QPointF &	point1,
		const QPointF &	point2
	)

friend

Returns a QPointF object that is formed by subtracting point2 from point1, each component is subtracted separately.

See also: QPointF::operator-=()

const QPointF operator/	(	const QPointF &	point,
		qreal	factor
	)

friend

Returns the QPointF object formed by dividing both components of the given point by the given factor.

See also: QPointF::operator/=()

QDataStream & operator<<	(	QDataStream &	stream,
		const QPointF &	pointF
	)

Refer to Serializing Data Types for additional information.

bool operator==	(	const QPointF &	point1,
		const QPointF &	point2
	)

friend

Returns true if point1 is equal to point2, otherwise returns false.

QDataStream & operator>>	(	QDataStream &	stream,
		QPointF &	pointF
	)

Refer to Serializing Data Types for additional information.

Public Methods

Friends

Related Functions

Detailed Description

Constructor & Destructor Documentation

Method Documentation

Friends And Related Function Documentation