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QPolygon Class Reference
[com.trolltech.qt.gui module]

The QPolygon class provides a vector of points using integer precision. More...


Detailed Description

The QPolygon class provides a vector of points using integer precision.

A QPolygon object is a QVector<QPoint>. The easiest way to add points to a QPolygon is to use QVector's streaming operator, as illustrated below:

            QPolygon polygon;
            polygon << QPoint(10, 20) << QPoint(20, 30);

In addition to the functions provided by QVector, QPolygon provides some point-specific functions.

Each point in a polygon can be retrieved by passing its index to the point() function. To populate the polygon, QPolygon provides the setPoint() function to set the point at a given index, the setPoints() function to set all the points in the polygon (resizing it to the given number of points), and the putPoints() function which copies a number of given points into the polygon from a specified index (resizing the polygon if necessary).

QPolygon provides the boundingRect and translate functions for geometry functions. Use the QMatrix::map() function for more general transformations of QPolygons.

The QPolygon class is implicitly shared.

See also QVector, QPolygonF, and QLine.


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Qt Jambi 4.3.2_01