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The QPoint class defines a point in the plane. More...
#include <qpoint.h>
A point is specified by an x coordinate and a y coordinate.
The coordinate type is QCOORD (a 32-bit integer). The minimum value of QCOORD is QCOORD_MIN (-2147483648) and the maximum value is QCOORD_MAX (2147483647).
The coordinates are accessed by the functions x() and y(); they can be set by setX() and setY() or by the reference functions rx() and ry().
Given a point p, the following statements are all equivalent:
        p.setX( p.x() + 1 );
        p += QPoint( 1, 0 );
        p.rx()++;
    
 
A QPoint can also be used as a vector. Addition and subtraction of QPoints are defined as for vectors (each component is added separately). You can divide or multiply a QPoint by an int or a double. The function manhattanLength() gives an inexpensive approximation of the length of the QPoint interpreted as a vector.
Example:
        //QPoint oldPos is defined somewhere else
        MyWidget::mouseMoveEvent( QMouseEvent *e )
        {
            QPoint vector = e->pos() - oldPos;
            if ( vector.manhattanLength() > 3 )
            ... //mouse has moved more than 3 pixels since oldPos
        }
    
 
QPoints can be compared for equality or inequality, and they can be written to and read from a QStream.
See also QPointArray, QSize, QRect, Graphics Classes, and Image Processing Classes.
Constructs a point with coordinates (0, 0) (isNull() returns TRUE).
Constructs a point with x value xpos and y value ypos.
Returns TRUE if both the x value and the y value are 0; otherwise returns FALSE.
This is a useful, and quick to calculate, approximation to the true length: sqrt(pow(x(),2)+pow(y(),2)).
Multiplies this point's x and y by c, and returns a reference to this point.
Example:
        QPoint p( -1, 4 );
        p *= 2;            // p becomes (-2,8)
    
 
Multiplies this point's x and y by c, and returns a reference to this point.
Example:
        QPoint p( -1, 4 );
        p *= 2.5;          // p becomes (-3,10)
    
 
Note that the result is truncated because points are held as integers.
Adds point p to this point and returns a reference to this point.
Example:
        QPoint p(  3, 7 );
        QPoint q( -1, 4 );
        p += q;            // p becomes (2,11)
    
 
Subtracts point p from this point and returns a reference to this point.
Example:
        QPoint p(  3, 7 );
        QPoint q( -1, 4 );
        p -= q;            // p becomes (4,3)
    
 
Divides both x and y by c, and returns a reference to this point.
Example:
        QPoint p( -2, 8 );
        p /= 2;            // p becomes (-1,4)
    
 
Divides both x and y by c, and returns a reference to this point.
Example:
        QPoint p( -3, 10 );
        p /= 2.5;           // p becomes (-1,4)
    
 
Note that the result is truncated because points are held as integers.
Returns a reference to the x coordinate of the point.
Using a reference makes it possible to directly manipulate x.
Example:
        QPoint p( 1, 2 );
        p.rx()--;         // p becomes (0, 2)
    
 
See also ry().
Returns a reference to the y coordinate of the point.
Using a reference makes it possible to directly manipulate y.
Example:
        QPoint p( 1, 2 );
        p.ry()++;         // p becomes (1, 3)
    
 
See also rx().
Sets the x coordinate of the point to x.
Example: t14/cannon.cpp.
Sets the y coordinate of the point to y.
Example: t14/cannon.cpp.
Returns the x coordinate of the point.
Examples: canvas/canvas.cpp, chart/canvasview.cpp, dirview/dirview.cpp, fileiconview/qfileiconview.cpp, helpsystem/tooltip.cpp, life/life.cpp, and t14/cannon.cpp.
Returns the y coordinate of the point.
Examples: canvas/canvas.cpp, chart/canvasview.cpp, fileiconview/qfileiconview.cpp, helpsystem/tooltip.cpp, life/life.cpp, t14/cannon.cpp, and themes/wood.cpp.
Returns TRUE if p1 and p2 are not equal; otherwise returns FALSE.
Returns the QPoint formed by multiplying both components of p by c.
Returns the QPoint formed by multiplying both components of p by c.
Returns the QPoint formed by multiplying both components of p by c.
Note that the result is truncated because points are held as integers.
Returns the QPoint formed by multiplying both components of p by c.
Note that the result is truncated because points are held as integers.
Returns the sum of p1 and p2; each component is added separately.
Returns p2 subtracted from p1; each component is subtracted separately.
Returns the QPoint formed by changing the sign of both components of p, equivalent to QPoint(0,0) - p.
Returns the QPoint formed by dividing both components of p by c.
Returns the QPoint formed by dividing both components of p by c.
Note that the result is truncated because points are held as integers.
Writes point p to the stream s and returns a reference to the stream.
See also Format of the QDataStream operators.
Returns TRUE if p1 and p2 are equal; otherwise returns FALSE.
Reads a QPoint from the stream s into point p and returns a reference to the stream.
See also Format of the QDataStream operators.
This file is part of the Qt toolkit. Copyright © 1995-2007 Trolltech. All Rights Reserved.
| Copyright © 2007 Trolltech | Trademarks | Qt 3.3.8 |