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The QPointArray class provides an array of points. More...
#include <qpointarray.h>
Inherits QArray.
The QPointArray is an array of QPoint objects. In addition to the functions provided by QArray, QPointArray provides some point-specific functions.
For convenient reading and writing of the point data: setPoints(), putPoints(), point(), and setPoint().
For geometry operations: boundingRect() and translate(). There is also a QWMatrix::map() function for more general transformation of QPointArrays.
QPointArray is used by QPainter::drawLineSegments(), QPainter::drawPolyline(), QPainter::drawPolygon() and QPainter::drawQuadBezier(), among other things.
Note that since this class is a QArray, it is explicitly shared and works with shallow copies by default.
See also QPainter, QWMatrix and QArray.
Examples: desktop/desktop.cpp picture/picture.cpp
Constructs a null point array.
See also isNull().
Constructs a point array from the rectangle r.
If closed is FALSE, then the point array just contains the following four points in the listed order: r.topLeft(), r.topRight(), r.bottomRight() and r.bottomLeft().
If closed is TRUE, then a fifth point is set to r.topLeft().
Constructs a shallow copy of the point array a.
See also copy().
Constructs a point array with nPoints points, taken from the points array.
Equivalent to setPoints(nPoints,points).
Constructs a point array with room for size points. Makes a null array if size == 0.
See also resize() and isNull().
Destructs the point array.
Returns the bounding rectangle of the points in the array, or QRect(0,0,0,0) if the array is empty.
Creates a deep copy of the array.
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. The resulting array has sufficient resolution for pixel accuracy (see the overloaded function which takes an additional QWMatrix parameter).
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.
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, transformed by the matrix xf. The resulting array has sufficient resolution for pixel accuracy.
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.
Sets the points of the array to those describing an ellipse with size w by h and position (x, y ).
The returned array has sufficient resolution for use as pixels.
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().
Returns the point at position index in the array.
Returns the point at position index in the array in *x and *y.
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 (typcailly due to lack of memory).
The example code creates an array with three points: (1,2), (3,4) and (5,6):
QPointArray a( 1 );
a[0] = QPoint( 1, 2 );
static QCOORD points[] = { 3,4, 5,6 };
a.putPoints( 1, 2, points );
This function differs from setPoints() in that it does not resize the array unless the array size is exceeded.
See also resize() and setPoints().
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 (typically due to lack of memory).
The example code creates an array with two points (1,2), (3,4) and (5,6):
QPointArray a( 1 );
a[0] = QPoint( 1, 2 );
a.putPoints( 1, 2, 3,4, 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().
Returns the Bezier points for the four control points in this array.
Equivalent to setPoint( i, p.x(), p.y() ).
Sets the point at position index in the array to (x,y).
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 (normally due to lack of memory).
The example code creates an array with two points (1,2) and (3,4):
static QCOORD points[] = { 1,2, 3,4 };
QPointArray a;
a.setPoints( 2, points );
See also resize() and putPoints().
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 (typically due to lack of memory).
The example code creates an array with two points (1,2) and (3,4):
QPointArray a;
a.setPoints( 2, 1,2, 3,4 );
See also resize() and putPoints().
Translates all points in the array (dx,dy).
[static]For internal use only.
For internal use only.
Reads a point array from the stream and returns a reference to the stream.
See also Format of the QDataStream operators
Writes a point array to the stream and returns a reference to the stream.
See also Format of the QDataStream operators
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