QLineF¶
Synopsis¶
Functions¶
def
__eq__
(d)def
__mul__
(, m)def
__mul__
(, m)def
__ne__
(d)def
__reduce__
()def
__repr__
()def
angle
()def
angle
(l)def
angleTo
(l)def
center
()def
dx
()def
dy
()def
intersect
(l)def
isNull
()def
length
()def
normalVector
()def
p1
()def
p2
()def
pointAt
(t)def
setAngle
(angle)def
setLength
(len)def
setLine
(x1, y1, x2, y2)def
setP1
(p1)def
setP2
(p2)def
setPoints
(p1, p2)def
toLine
()def
toTuple
()def
translate
(dx, dy)def
translate
(p)def
translated
(dx, dy)def
translated
(p)def
unitVector
()def
x1
()def
x2
()def
y1
()def
y2
()
Detailed Description¶
A
QLineF
describes a finite length line (or line segment) on a twodimensional surface.QLineF
defines the start and end points of the line using floating point accuracy for coordinates. Use thetoLine()
function to retrieve an integer based copy of this line.
The positions of the line’s start and end points can be retrieved using the
p1()
,x1()
,y1()
,p2()
,x2()
, andy2()
functions. Thedx()
anddy()
functions return the horizontal and vertical components of the line, respectively.The line’s length can be retrieved using the
length()
function, and altered using thesetLength()
function. Similarly,angle()
andsetAngle()
are respectively used for retrieving and altering the angle of the line. Use theisNull()
function to determine whether theQLineF
represents a valid line or a null line.The
intersect()
function determines theIntersectType
for this line and a given line, while theangleTo()
function returns the angle between the lines. In addition, theunitVector()
function returns a line that has the same starting point as this line, but with a length of only 1, while thenormalVector()
function returns a line that is perpendicular to this line with the same starting point and length.Finally, the line can be translated a given offset using the
translate()
function, and can be traversed using thepointAt()
function.
Constraints¶

class
QLineF
¶ Constructs a null line.
Construct a
QLineF
object from the given integerbasedline
.See also
Constructs a line object that represents the line between
p1
andp2
.Constructs a line object that represents the line between (
x1
,y1
) and (x2
,y2
).

PySide2.QtCore.QLineF.
IntersectType
¶ Describes the intersection between two lines.
Constant
Description
QLineF.NoIntersection
Indicates that the lines do not intersect; i.e. they are parallel.
QLineF.UnboundedIntersection
The two lines intersect, but not within the range defined by their lengths. This will be the case if the lines are not parallel.
intersect()
will also return this value if the intersect point is within the start and end point of only one of the lines.QLineF.BoundedIntersection
The two lines intersect with each other within the start and end points of each line.
See also

PySide2.QtCore.QLineF.
__reduce__
()¶  Return type
PyObject

PySide2.QtCore.QLineF.
__repr__
()¶  Return type
PyObject

PySide2.QtCore.QLineF.
angle
()¶  Return type
qreal
Returns the angle of the line in degrees.
The return value will be in the range of values from 0.0 up to but not including 360.0. The angles are measured counterclockwise from a point on the xaxis to the right of the origin (x > 0).
See also

PySide2.QtCore.QLineF.
angle
(l)  Parameters
l –
QLineF
 Return type
qreal
Returns the angle (in degrees) between this line and the given
line
, taking the direction of the lines into account. If the lines do not intersect within their range, it is the intersection point of the extended lines that serves as origin (seeUnboundedIntersection
).When the lines are parallel, this function returns 0 if they have the same direction; otherwise it returns 180.
See also

PySide2.QtCore.QLineF.
angleTo
(l)¶  Parameters
l –
QLineF
 Return type
qreal
Returns the angle (in degrees) from this line to the given
line
, taking the direction of the lines into account. If the lines do not intersect within their range, it is the intersection point of the extended lines that serves as origin (seeUnboundedIntersection
).The returned value represents the number of degrees you need to add to this line to make it have the same angle as the given
line
, going counterclockwise.See also

PySide2.QtCore.QLineF.
center
()¶  Return type
Returns the center point of this line. This is equivalent to 0.5 *
p1()
+ 0.5 *p2()
.

PySide2.QtCore.QLineF.
dx
()¶  Return type
qreal
Returns the horizontal component of the line’s vector.

PySide2.QtCore.QLineF.
dy
()¶  Return type
qreal
Returns the vertical component of the line’s vector.

static
PySide2.QtCore.QLineF.
fromPolar
(length, angle)¶  Parameters
length –
qreal
angle –
qreal
 Return type
Returns a
QLineF
with the givenlength
andangle
.The first point of the line will be on the origin.
Positive values for the angles mean counterclockwise while negative values mean the clockwise direction. Zero degrees is at the 3 o’clock position.

PySide2.QtCore.QLineF.
intersect
(l)¶  Parameters
l –
QLineF
 Return type
(intersectType, intersectionPoint)
Returns a value indicating whether or not this line intersects with the given
line
.The actual intersection point is extracted to
intersectionPoint
(if the pointer is valid). If the lines are parallel, the intersection point is undefined.

PySide2.QtCore.QLineF.
isNull
()¶  Return type
bool
Returns
true
if the line is not set up with valid start and end point; otherwise returnsfalse
.

PySide2.QtCore.QLineF.
length
()¶  Return type
qreal
Returns the length of the line.
See also

PySide2.QtCore.QLineF.
normalVector
()¶  Return type
Returns a line that is perpendicular to this line with the same starting point and length.
See also

PySide2.QtCore.QLineF.
__ne__
(d)¶  Parameters
d –
QLineF
 Return type
bool
Returns
true
if the givenline
is not the same as this line.A line is different from another line if their start or end points differ, or the internal order of the points is different.

PySide2.QtCore.QLineF.
__mul__
(m)  Parameters
m –
QTransform
 Return type

PySide2.QtCore.QLineF.
__eq__
(d)¶  Parameters
d –
QLineF
 Return type
bool
Returns
true
if the givenline
is the same as this line.A line is identical to another line if the start and end points are identical, and the internal order of the points is the same.

PySide2.QtCore.QLineF.
pointAt
(t)¶  Parameters
t –
qreal
 Return type
Returns the point at the parameterized position specified by
t
. The function returns the line’s start point if t = 0, and its end point if t = 1.

PySide2.QtCore.QLineF.
setAngle
(angle)¶  Parameters
angle –
qreal
Sets the angle of the line to the given
angle
(in degrees). This will change the position of the second point of the line such that the line has the given angle.Positive values for the angles mean counterclockwise while negative values mean the clockwise direction. Zero degrees is at the 3 o’clock position.
See also

PySide2.QtCore.QLineF.
setLength
(len)¶  Parameters
len –
qreal
Sets the length of the line to the given
length
.QLineF
will move the end point p2()
 of the line to give the line its new length.If the line is a null line, the length will remain zero regardless of the length specified.

PySide2.QtCore.QLineF.
setLine
(x1, y1, x2, y2)¶  Parameters
x1 –
qreal
y1 –
qreal
x2 –
qreal
y2 –
qreal
Sets this line to the start in
x1
,y1
and end inx2
,y2
.

PySide2.QtCore.QLineF.
setP1
(p1)¶  Parameters
p1 –
QPointF
Sets the starting point of this line to
p1
.

PySide2.QtCore.QLineF.
setPoints
(p1, p2)¶ 
Sets the start point of this line to
p1
and the end point of this line top2
.

PySide2.QtCore.QLineF.
toLine
()¶  Return type
Returns an integer based copy of this line.
Note that the returned line’s start and end points are rounded to the nearest integer.
See also
QLineF()

PySide2.QtCore.QLineF.
toTuple
()¶  Return type
PyObject

PySide2.QtCore.QLineF.
translate
(p)¶  Parameters
p –
QPointF
Translates this line by the given
offset
.

PySide2.QtCore.QLineF.
translate
(dx, dy)  Parameters
dx –
qreal
dy –
qreal
This is an overloaded function.
Translates this line the distance specified by
dx
anddy
.

PySide2.QtCore.QLineF.
translated
(p)¶ 
Returns this line translated by the given
offset
.

PySide2.QtCore.QLineF.
translated
(dx, dy)  Parameters
dx –
qreal
dy –
qreal
 Return type
This is an overloaded function.
Returns this line translated the distance specified by
dx
anddy
.

PySide2.QtCore.QLineF.
unitVector
()¶  Return type
Returns the unit vector for this line, i.e a line starting at the same point as this line with a length of 1.0.
See also

PySide2.QtCore.QLineF.
x1
()¶  Return type
qreal
Returns the xcoordinate of the line’s start point.
See also

PySide2.QtCore.QLineF.
x2
()¶  Return type
qreal
Returns the xcoordinate of the line’s end point.
See also

PySide2.QtCore.QLineF.
y1
()¶  Return type
qreal
Returns the ycoordinate of the line’s start point.
See also
© 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.