|  | Home · All Classes · Modules

# QPolygonF Class Reference
[QtGui module]

The QPolygonF class provides a vector of points using floating point precision. More...

### Methods

- __init__ (self)
- __init__ (self, QPolygonF)
- __init__ (self, list-of-QPointF)
- __init__ (self, QRectF)
- __init__ (self, QPolygon)
- __init__ (self, int)
- append (self, QPointF value)
- QPointF at (self, int i)
- QRectF boundingRect (self)
- clear (self)
- bool contains (self, QPointF value)
- bool containsPoint (self, QPointF, Qt.FillRule)
- int count (self, QPointF value)
- int count (self)
- sip.voidptr data (self)
- fill (self, QPointF value, int size = -1)
- QPointF first (self)
- int indexOf (self, QPointF value, int from = 0)
- insert (self, int i, QPointF value)
- QPolygonF intersected (self, QPolygonF)
- bool isClosed (self)
- bool isEmpty (self)
- QPointF last (self)
- int lastIndexOf (self, QPointF value, int from = -1)
- QPolygonF mid (self, int pos, int length = -1)
- prepend (self, QPointF value)
- remove (self, int i)
- remove (self, int i, int count)
- replace (self, int i, QPointF value)
- int size (self)
- QPolygonF subtracted (self, QPolygonF)
- QPolygon toPolygon (self)
- translate (self, QPointF)
- translate (self, float, float)
- QPolygonF translated (self, QPointF)
- QPolygonF translated (self, float, float)
- QPolygonF united (self, QPolygonF)
- QPointF value (self, int i)
- QPointF value (self, int i, QPointF defaultValue)

### Special Methods

- QPolygonF __add__ (self, QPolygonF other)
- int __contains__ (self, QPointF value)
- __delitem__ (self, int i)
- __delitem__ (self, slice slice)
- bool __eq__ (self, QPolygonF other)
- QPointF __getitem__ (self, int i)
- QPolygonF __getitem__ (self, slice slice)
- QPolygonF __iadd__ (self, QPolygonF other)
- QPolygonF __iadd__ (self, QPointF value)
- int __len__ (self)
- QPolygonF __mul__ (self, QMatrix)
- QPolygonF __mul__ (self, QTransform)
- bool __ne__ (self, QPolygonF other)
- __setitem__ (self, int i, QPointF value)
- __setitem__ (self, slice slice, QPolygonF list)

## Detailed Description

The QPolygonF class provides a vector of points using floating point precision.

A QPolygonF is a QVector<QPointF>. The easiest way to add points to a QPolygonF is to use its streaming operator, as illustrated below:

             QPolygonF polygon;
             polygon << QPointF(10.4, 20.5) << QPointF(20.2, 30.2);

In addition to the functions provided by QVector, QPolygonF provides the boundingRect() and translate() functions for geometry operations. Use the QMatrix.map() function for more general transformations of QPolygonFs.

QPolygonF also provides the isClosed() function to determine whether a polygon's start and end points are the same, and the toPolygon() function returning an integer precision copy of this polygon.

The QPolygonF class is implicitly shared.

See also QVector, QPolygon, and QLineF.

## Method Documentation

### QPolygonF.__init__ (self)

Constructs a polygon with no points.

See also QVector.isEmpty().

### QPolygonF.__init__ (self, QPolygonF)

Constructs a polygon of the given size. Creates an empty polygon if size == 0.

See also QVector.isEmpty().

### QPolygonF.__init__ (self, list-of-QPointF)

Constructs a copy of the given polygon.

### QPolygonF.__init__ (self, QRectF)

Constructs a polygon containing the specified points.

### QPolygonF.__init__ (self, QPolygon)

Constructs a closed polygon from the specified rectangle.

The polygon contains the four vertices of the rectangle in clockwise order starting and ending with the top-left vertex.

See also isClosed().

### QPolygonF.__init__ (self, int)

Constructs a float based polygon from the specified integer based polygon.

See also toPolygon().

### QPolygonF.append (self, QPointF value)

### QPointF QPolygonF.at (self, int i)

### QRectF QPolygonF.boundingRect (self)

Returns the bounding rectangle of the polygon, or QRectF(0,0,0,0) if the polygon is empty.

See also QVector.isEmpty().

### QPolygonF.clear (self)

### bool QPolygonF.contains (self, QPointF value)

### bool QPolygonF.containsPoint (self, QPointF, Qt.FillRule)

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.

### int QPolygonF.count (self, QPointF value)

### int QPolygonF.count (self)

### sip.voidptr QPolygonF.data (self)

### QPolygonF.fill (self, QPointF value, int size = -1)

### QPointF QPolygonF.first (self)

### int QPolygonF.indexOf (self, QPointF value, int from = 0)

### QPolygonF.insert (self, int i, QPointF value)

### QPolygonF QPolygonF.intersected (self, QPolygonF)

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.

### bool QPolygonF.isClosed (self)

Returns true if the polygon is closed; otherwise returns false.

A polygon is said to be closed if its start point and end point are equal.

See also QVector.first() and QVector.last().

### bool QPolygonF.isEmpty (self)

### QPointF QPolygonF.last (self)

### int QPolygonF.lastIndexOf (self, QPointF value, int from = -1)

### QPolygonF QPolygonF.mid (self, int pos, int length = -1)

### QPolygonF.prepend (self, QPointF value)

### QPolygonF.remove (self, int i)

### QPolygonF.remove (self, int i, int count)

### QPolygonF.replace (self, int i, QPointF value)

### int QPolygonF.size (self)

### QPolygonF QPolygonF.subtracted (self, QPolygonF)

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.

### QPolygon QPolygonF.toPolygon (self)

Creates and returns a QPolygon by converting each QPointF to a QPoint.

See also QPointF.toPoint().

### QPolygonF.translate (self, QPointF)

Translate all points in the polygon by the given offset.

See also translated().

### QPolygonF.translate (self, float, float)

This is an overloaded function.

Translates all points in the polygon by (dx, dy).

See also translated().

### QPolygonF QPolygonF.translated (self, QPointF)

Returns a copy of the polygon that is translated by the given offset.

This function was introduced in Qt 4.6.

See also translate().

### QPolygonF QPolygonF.translated (self, float, float)

This is an overloaded function.

Returns a copy of the polygon that is translated by (dx, dy).

This function was introduced in Qt 4.6.

See also translate().

### QPolygonF QPolygonF.united (self, QPolygonF)

Returns a polygon which is the union 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.

See also intersected() and subtracted().

### QPointF QPolygonF.value (self, int i)

### QPointF QPolygonF.value (self, int i, QPointF defaultValue)

### QPolygonF QPolygonF.__add__ (self, QPolygonF other)

### int QPolygonF.__contains__ (self, QPointF value)

### QPolygonF.__delitem__ (self, int i)

### QPolygonF.__delitem__ (self, slice slice)

### bool QPolygonF.__eq__ (self, QPolygonF other)

### QPointF QPolygonF.__getitem__ (self, int i)

### QPolygonF QPolygonF.__getitem__ (self, slice slice)

### QPolygonF QPolygonF.__iadd__ (self, QPolygonF other)

### QPolygonF QPolygonF.__iadd__ (self, QPointF value)

### int QPolygonF.__len__ (self)

### QPolygonF QPolygonF.__mul__ (self, QMatrix)

### QPolygonF QPolygonF.__mul__ (self, QTransform)

### bool QPolygonF.__ne__ (self, QPolygonF other)

### QPolygonF.__setitem__ (self, int i, QPointF value)

### QPolygonF.__setitem__ (self, slice slice, QPolygonF list)