class QPolygonF

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

Synopsis

Methods

Static functions

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

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

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

In addition to the functions provided by QList, QPolygonF provides the boundingRect() and translate() functions for geometry operations. Use the 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

QPolygon QLineF

__init__()

Constructs a polygon with no points.

See also

isEmpty()

__init__(v)
Parameters:

v – .list of QPointF

Constructs a polygon containing the specified points.

__init__(a)
Parameters:

aQPolygon

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

See also

toPolygon()

__init__(r)
Parameters:

rQRectF

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()

append(arg__1)
Parameters:

arg__1QPointF

append(l)
Parameters:

l – .list of QPointF

at(i)
Parameters:

i – int

Return type:

QPointF

back()
Return type:

QPointF

boundingRect()
Return type:

QRectF

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

See also

isEmpty()

capacity()
Return type:

int

clear()
constData()
Return type:

QPointF

constFirst()
Return type:

QPointF

constLast()
Return type:

QPointF

containsPoint(pt, fillRule)
Parameters:
Return type:

bool

Returns true if the given point is inside the polygon according to the specified fillRule; otherwise returns false.

count()
Return type:

int

data()
Return type:

QPointF

empty()
Return type:

bool

first()
Return type:

QPointF

first(n)
Parameters:

n – int

Return type:

.list of QPointF

static fromList(list)
Parameters:

list – .list of QPointF

Return type:

.list of QPointF

static fromVector(vector)
Parameters:

vector – .list of QPointF

Return type:

.list of QPointF

front()
Return type:

QPointF

insert(arg__1, arg__2)
Parameters:
  • arg__1 – int

  • arg__2QPointF

intersected(r)
Parameters:

rQPolygonF

Return type:

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.

See also

intersects()

intersects(r)
Parameters:

rQPolygonF

Return type:

bool

Returns true if the current polygon intersects at any point the given polygon p. Also returns true if the current polygon contains or is contained by any part of p.

Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.

See also

intersected()

isClosed()
Return type:

bool

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

last()

isEmpty()
Return type:

bool

isSharedWith(other)
Parameters:

other – .list of QPointF

Return type:

bool

last()
Return type:

QPointF

last(n)
Parameters:

n – int

Return type:

.list of QPointF

length()
Return type:

int

static maxSize()
Return type:

int

max_size()
Return type:

int

mid(pos[, len=-1])
Parameters:
  • pos – int

  • len – int

Return type:

.list of QPointF

move(from, to)
Parameters:
  • from – int

  • to – int

__mul__(m)
Parameters:

mQTransform

Return type:

QPolygonF

__add__(l)
Parameters:

l – .list of QPointF

Return type:

.list of QPointF

operator(i)
Parameters:

i – int

Return type:

QPointF

pop_back()
pop_front()
prepend(arg__1)
Parameters:

arg__1QPointF

push_back(arg__1)
Parameters:

arg__1QPointF

push_front(arg__1)
Parameters:

arg__1QPointF

remove(i[, n=1])
Parameters:
  • i – int

  • n – int

removeAll(arg__1)
Parameters:

arg__1QPointF

removeAt(i)
Parameters:

i – int

removeFirst()
removeLast()
removeOne(arg__1)
Parameters:

arg__1QPointF

reserve(size)
Parameters:

size – int

resize(size)
Parameters:

size – int

resizeForOverwrite(size)
Parameters:

size – int

shrink_to_fit()
size()
Return type:

int

sliced(pos)
Parameters:

pos – int

Return type:

.list of QPointF

sliced(pos, n)
Parameters:
  • pos – int

  • n – int

Return type:

.list of QPointF

squeeze()
subtracted(r)
Parameters:

rQPolygonF

Return type:

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.

swap(other)
Parameters:

otherQPolygonF

Swaps polygon other with this polygon. This operation is very fast and never fails.

swapItemsAt(i, j)
Parameters:
  • i – int

  • j – int

takeAt(i)
Parameters:

i – int

Return type:

QPointF

toList()
Return type:

.list of QPointF

toPolygon()
Return type:

QPolygon

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

See also

toPoint()

toVector()
Return type:

.list of QPointF

translate(offset)
Parameters:

offsetQPointF

Translate all points in the polygon by the given offset.

See also

translated()

translate(dx, dy)
Parameters:
  • dx – float

  • dy – float

This is an overloaded function.

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

See also

translated()

translated(offset)
Parameters:

offsetQPointF

Return type:

QPolygonF

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

See also

translate()

translated(dx, dy)
Parameters:
  • dx – float

  • dy – float

Return type:

QPolygonF

This is an overloaded function.

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

See also

translate()

united(r)
Parameters:

rQPolygonF

Return type:

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.

value(i)
Parameters:

i – int

Return type:

QPointF