QPointArray(3qt)

NAME
QPointArray - Array of points

SYNOPSIS

#include <qpointarray.h>

Inherits QArray.

  Public Members
QPointArray ()
QPointArray ( int size )
QPointArray ( const QPointArray & a )
QPointArray ( const QRect & r, bool closed=FALSE )
QPointArray ( int nPoints, const QCOORD * points )
QPointArray& operator= ( const QPointArray & a )
bool fill ( const QPoint & p, int size = -1 )
QPointArray copy () const
void translate ( int dx, int dy )
void point ( uint i, int * x, int * y ) const
QPoint point ( uint i ) const
void setPoint ( uint i, int x, int y )
void setPoint ( uint i, const QPoint & p )
bool setPoints ( int nPoints, const QCOORD * points )
bool setPoints ( int nPoints, int firstx, int firsty, ... )
bool putPoints ( int index, int nPoints, const QCOORD * points )
bool putPoints ( int index, int nPoints, int firstx, int firsty, ... )
QPoint at ( uint i ) const
QPointVal operator[] ( int i )
QPointVal operator[] ( uint i )
QPoint operator[] ( int i ) const
QPoint operator[] ( uint i ) const
QRect boundingRect () const
void makeArc ( int x, int y, int w, int h, int a1, int a2 )
void makeEllipse ( int x, int y, int w, int h )
QPointArray quadBezier () const

RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
QDataStream & operator<< (QDataStream & s, const QPointArray & a)
QDataStream & operator>> (QDataStream & s, QPointArray & a)

DESCRIPTION
The QPointArray class provides an array of points.

QPointArray is used by the QPainter to draw line segments, polylines, polygons and Bezier curves.

The QPointArray is not an array of QPoint, instead it contains a platform dependent point type to make the QPainter functions more efficient (no conversion needed). On the other hand, QPointArray has member functions that operate on QPoint to make programming easier.

Note that since this class is a QArray, it is explicitly shared and works with shallow copies by default.

Examples: desktop/desktop.cpp drawdemo/drawdemo.cpp picture/picture.cpp aclock/aclock.cpp

MEMBER FUNCTION DOCUMENTATION

QPointArray::QPointArray ()
Constructs a null point array.

See also: isNull().

QPointArray::QPointArray ( const QRect & r, bool closed=FALSE )
Constructs a point array from the rectangle r.

If closed is FALSE, then the point array will contain the following four points (in the listed order):

1   r.topLeft()

2   r.topRight()

3   r.bottomRight()

4   r.bottomLeft()

If closed is TRUE, then a fifth point is set to r.topLeft() to close the point array.

QPointArray::QPointArray ( const QPointArray & a )
Constructs a shallow copy of the point array a.

See also: copy().

QPointArray::QPointArray ( int nPoints, const QCOORD * points )
Constructs a point array with nPoints points, taken from the points array.

Equivalent to setPoints(nPoints,points).

QPointArray::QPointArray ( int size )
Constructs a point array with room for size points. Makes a null array if size == 0.

See also: resize() and isNull().

QPoint QPointArray::at ( uint index ) const
Returns the point at position index in the array.

See also: operator[].

QRect QPointArray::boundingRect () const
Returns the bounding rectangle of the points in the array, or QRect(0,0,0,0) if the array is empty.

QPointArray QPointArray::copy () const
Creates a deep copy of the array.

bool QPointArray::fill ( const QPoint & p, int size = -1 )
Fills the point array with the point p. If size is specified as different from -1, then the array will be resized before filled.

Returns TRUE if successful, or FALSE if the memory cannot be allocated (only when size != -1).

See also: resize().

void QPointArray::makeArc ( int x, int y, int w, int h, int a1, int a2 )
Sets the points of the array to those describing an arc of an ellipse with size w by h and position (x, y ), starting from angle \a1, spanning a2. Angles are specified in 16ths of a degree, i.e. a full circle equals 5760 (16*360). Positive values mean counter-clockwise while negative values mean clockwise direction. Zero degrees is at the 3'o clock position.

void QPointArray::makeEllipse ( int xx, int yy, int w, int h )
Sets the points of the array to those describing an ellipse with size w by h and position (x, y ).

QPointArray & QPointArray::operator= ( const QPointArray & a )
Assigns a shallow copy of a to this point array and returns a reference to this point array.

Equivalent to assign( a ).

See also: copy().

QPoint QPointArray::operator[] ( int i ) const
Returns the point at position index in the array.

QPoint QPointArray::operator[] ( uint i ) const
Returns the point at position index in the array.

QPointVal QPointArray::operator[] ( int index )
Returns a reference to the point at position index in the array.

QPointVal QPointArray::operator[] ( uint index )
Returns a reference to the point at position index in the array.

QPoint QPointArray::point ( uint index ) const
Returns the point at position index in the array.

void QPointArray::point ( uint index, int * x, int * y ) const
Returns the point at position index in the array in *x and *y.

Examples: drawdemo/drawdemo.cpp

bool QPointArray::putPoints ( int index, int nPoints, const QCOORD * points )
Copies nPoints points from the points array into this point array. Will resize this point array if index+nPoints exceeds the size of the array.

Returns TRUE if successful, or FALSE if the array could not be resized.

Example:

    QPointArray a( 1 );
    a[0] = QPoint( 1, 2 );
    static QCOORD points[] = { 3,4, 5,6 };
    a.putPoints( 1, 2, points );

The example code creates an array with three points: (1,2), (3,4) and (5,6).

This function differs from setPoints() in that it does not resize the array unless the array size is exceeded.

See also: resize() and setPoints().

bool QPointArray::putPoints ( int index, int nPoints, int firstx, int firsty, ... )
Copies nPoints points from the variable argument list into this point array. Will resize this point array if index+nPoints exceeds the size of the array.

Returns TRUE if successful, or FALSE if the array could not be resized.

Example:

    QPointArray a( 1 );
    a[0] = QPoint( 1, 2 );
    a.putPoints( 1, 2, 3,4, 5,6 );

The example code creates an array with two points (1,2), (3,4) and (5,6).

This function differs from setPoints() because it does not resize the array unless the array size is exceeded.

See also: resize() and setPoints().

QPointArray QPointArray::quadBezier () const
Returns the Bezier points for the four control points in this array.

Examples: drawdemo/drawdemo.cpp

void QPointArray::setPoint ( uint i, const QPoint & p )
Equivalent to setPoint( i, p.x(), p.y() ).

void QPointArray::setPoint ( uint index, int x, int y )
Sets the point at position index in the array to (x,y).

Examples: drawdemo/drawdemo.cpp

bool QPointArray::setPoints ( int nPoints, const QCOORD * points )
Resizes the array to nPoints and sets the points in the array to the values taken from points.

Returns TRUE if successful, or FALSE if the array could not be resized.

Example:

    static QCOORD points[] = { 1,2, 3,4 };
    QPointArray a;
    a.setPoints( 2, points );

The example code creates an array with two points (1,2) and (3,4).

See also: resize() and putPoints().

Examples: aclock/aclock.cpp

bool QPointArray::setPoints ( int nPoints, int firstx, int firsty, ... )
Resizes the array to nPoints and sets the points in the array to the values taken from the variable argument list.

Returns TRUE if successful, or FALSE if the array could not be resized.

Example:

    QPointArray a;
    a.setPoints( 2, 1,2, 3,4 );

The example code creates an array with two points (1,2) and (3,4).

See also: resize() and putPoints().

void QPointArray::translate ( int dx, int dy )
Translates all points in the array (dx,dy).

RELATED FUNCTION DOCUMENTATION

QDataStream & operator<< (QDataStream & s, const QPointArray & a)
Writes a point array to the stream and returns a reference to the stream.

The serialization format is:

1   The array size (UINT32)

2   The array points (QPoint)

QDataStream & operator>> (QDataStream & s, QPointArray & a)
Reads a point array from the stream and returns a reference to the stream.

SEE ALSO
http://www.troll.no/qt/qpointarray.html

COPYRIGHT
Copyright 1992-1997 Troll Tech AS. See the LICENSE file included in the distribution for a complete license statement.

AUTHOR
Generated automatically from the source code.