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[QtCore module]

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

#include <QPointF>

**QPointF**()**QPointF**( const QPoint &*point*)- bool
**isNull**() const - qreal &
**rx**() - qreal &
**ry**() - void
**setX**( qreal*x*) - void
**setY**( qreal*y*) - QPoint
**toPoint**() const - qreal
**x**() const - qreal
**y**() const - QPointF &
**operator*=**( qreal*factor*) - QPointF &
**operator+=**( const QPointF &*point*) - QPointF &
**operator-=**( const QPointF &*point*) - QPointF &
**operator/=**( qreal*divisor*)

- const QPointF
**operator-**( const QPointF &*point*)

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 and QPolygonF.

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

See also isNull().

Constructs a copy of the given *point*.

See also toPoint().

Constructs a point with the given coordinates (*x*, *y*).

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

Returns a reference to the x coordinate of this point.

Using a reference makes it possible to directly manipulate x. For example:

```
QPointF p(1.1, 2.5);
p.rx()--; // p becomes (0.1, 2.5)
```

Returns a reference to the y coordinate of this point.

Using a reference makes it possible to directly manipulate y. For example:

```
QPointF p(1.1, 2.5);
p.ry()++; // p becomes (1.1, 3.5)
```

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

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

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

See also QPointF().

Returns the x-coordinate of this point.

Returns the y-coordinate of this point.

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

```
QPointF p(-1.1, 4.1);
p *= 2.5; // p becomes (-2.75, 10.25)
```

See also operator/=().

Adds the given *point* to this point and returns a reference to this point. For example:

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

See also operator-=().

Subtracts the given *point* from this point and returns a reference to this point. For example:

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

See also operator+=().

Divides both x and y by the given *divisor*, and returns a reference to this point. For example:

```
QPointF p(-2.75, 10.25);
p /= 2.5; // p becomes (-1.1, 4.1)
```

See also operator*=().

This is an overloaded member function, provided for convenience.

Returns true if *p1* is not equal to *p2*; otherwise returns false.

This is an overloaded member function, provided for convenience.

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

See also QPointF::operator*=().

This is an overloaded member function, provided for convenience.

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

This is an overloaded member function, provided for convenience.

Returns a QPointF object that is the sum of the given points, *p1* and *p2*; each component is added separately.

See also QPointF::operator+=().

This is an overloaded member function, provided for convenience.

Returns a QPointF object that is formed by subtracting *p2* from *p1*; each component is subtracted separately.

See also QPointF::operator-=().

This is an overloaded member function, provided for convenience.

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

Equivalent to `QPointF(0,0) - point`.

This is an overloaded member function, provided for convenience.

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

See also QPointF::operator/=().

This is an overloaded member function, provided for convenience.

Writes the given *point* to the given *stream* and returns a reference to the stream.

See also Format of the QDataStream Operators.

This is an overloaded member function, provided for convenience.

Returns true if *p1* is equal to *p2*; otherwise returns false.

This is an overloaded member function, provided for convenience.

Reads a point from the given *stream* into the given *point* and returns a reference to the stream.

See also Format of the QDataStream Operators.

Copyright © 2008 Nokia | Trademarks | Qt 4.4.3 |