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The QPolygon class provides a vector of points using integer precision. More...
This class can be pickled.
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.
Constructs a polygon with no points.
See also QVector.isEmpty().
Constructs a polygon of the given size. Creates an empty polygon if size == 0.
See also QVector.isEmpty().
Constructs a copy of the given polygon.
See also setPoints().
Constructs a polygon containing the specified points.
See also setPoints().
Constructs a polygon from the given rectangle. If closed is false, the polygon just contains the four points of the rectangle ordered clockwise, otherwise the polygon's fifth point is set to rectangle.topLeft().
Note that the bottom-right corner of the rectangle is located at (rectangle.x() + rectangle.width(), rectangle.y() + rectangle.height()).
See also setPoints().
Returns the bounding rectangle of the polygon, or QRect(0, 0, 0, 0) if the polygon is empty.
See also QVector.isEmpty().
Returns true if the given point is inside the polygon according to the specified fillRule; otherwise returns false.
This function was introduced in Qt 4.3.
Returns a polygon which is the intersection of this polygon and r.
Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.
This function was introduced in Qt 4.3.
Extracts the coordinates of the point at the given index to *x and *y (if they are valid pointers).
See also setPoint().
Copies nPoints points from the variable argument list into this polygon from the given index.
The points are given as a sequence of integers, starting with firstx then firsty, and so on. The polygon is resized if index+nPoints exceeds its current size.
The example code creates a polygon with three points (4,5), (6,7) and (8,9), by expanding the polygon from 1 to 3 points:
QPolygon polygon(1);
polygon[0] = QPoint(4, 5);
polygon.putPoints(1, 2, 6,7, 8,9);
The following code has the same result, but here the putPoints() function overwrites rather than extends:
QPolygon polygon(3);
polygon.putPoints(0, 3, 4,5, 0,0, 8,9);
polygon.putPoints(1, 1, 6,7);
See also setPoints().
Sets the point at the given index to the point specified by (x, y).
See also point(), putPoints(), and setPoints().
This is an overloaded function.
Sets the point at the given index to the given point.
Resizes the polygon to nPoints and populates it with the given points.
The example code creates a polygon with two points (10, 20) and (30, 40):
static const int points[] = { 10, 20, 30, 40 };
QPolygon polygon;
polygon.setPoints(2, points);
See also setPoint() and putPoints().
This is an overloaded function.
Resizes the polygon to nPoints and populates it with the points specified by the variable argument list. The points are given as a sequence of integers, starting with firstx then firsty, and so on.
The example code creates a polygon with two points (10, 20) and (30, 40):
QPolygon polygon;
polygon.setPoints(2, 10, 20, 30, 40);
Returns a polygon which is r subtracted from this polygon.
Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.
This function was introduced in Qt 4.3.
Swaps polygon other with this polygon. This operation is very fast and never fails.
This function was introduced in Qt 4.8.
Translates all points in the polygon by (dx, dy).
See also translated().
This is an overloaded function.
Translates all points in the polygon by the given offset.
See also translated().
Returns a copy of the polygon that is translated by (dx, dy).
This function was introduced in Qt 4.6.
See also translate().
This is an overloaded function.
Returns a copy of the polygon that is translated by the given offset.
This function was introduced in Qt 4.6.
See also translate().
Returns a polygon which is the union of this polygon and r.
Set operations on polygons, will treat the polygons as areas, and implicitly close the polygon.
This function was introduced in Qt 4.3.
See also intersected() and subtracted().
| PyQt 4.9.4 for Windows | Copyright © Riverbank Computing Ltd and Nokia 2012 | Qt 4.8.2 |