QLineF¶
The QLineF
class provides a twodimensional vector using floating point precision. More…
Synopsis¶
Functions¶
def
__eq__
(d)def
__mul__
(, m)def
__ne__
(d)def
__reduce__
()def
__repr__
()def
angle
()def
angleTo
(l)def
center
()def
dx
()def
dy
()def
intersects
(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 the toLine()
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()
, and y2()
functions. The dx()
and dy()
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 the setLength()
function. Similarly, angle()
and setAngle()
are respectively used for retrieving and altering the angle of the line. Use the isNull()
function to determine whether the QLineF
represents a valid line or a null line.
The intersects()
function determines the IntersectionType
for this line and a given line, while the angleTo()
function returns the angle between the lines. In addition, the unitVector()
function returns a line that has the same starting point as this line, but with a length of only 1, while the normalVector()
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 the pointAt()
function.
Constraints¶
QLine
is limited to the minimum and maximum values for the int
type. Operations on a QLine
that could potentially result in values outside this range will result in undefined behavior.

class
PySide6.QtCore.
QLineF
¶ PySide6.QtCore.QLineF(line)
PySide6.QtCore.QLineF(QLineF)
PySide6.QtCore.QLineF(pt1, pt2)
PySide6.QtCore.QLineF(x1, y1, x2, y2)
 Parameters
x2 – float
y2 – float
line –
PySide6.QtCore.QLine
QLineF –
PySide6.QtCore.QLineF
pt1 –
PySide6.QtCore.QPointF
pt2 –
PySide6.QtCore.QPointF
y1 – float
x1 – float
Constructs a null line.
Construct a QLineF
object from the given integerbased line
.
See also
Constructs a line object that represents the line between p1
and p2
.
Constructs a line object that represents the line between (x1
, y1
) and (x2
, y2
).

PySide6.QtCore.QLineF.
IntersectionType
¶
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

PySide6.QtCore.QLineF.
__reduce__
()¶  Return type
object

PySide6.QtCore.QLineF.
__repr__
()¶  Return type
object

PySide6.QtCore.QLineF.
angle
()¶  Return type
float
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

PySide6.QtCore.QLineF.
angleTo
(l)¶  Parameters
 Return type
float
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 (see UnboundedIntersection
).
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

PySide6.QtCore.QLineF.
center
()¶  Return type
Returns the center point of this line. This is equivalent to 0.5 * p1()
+ 0.5 * p2()
.

PySide6.QtCore.QLineF.
dx
()¶  Return type
float
Returns the horizontal component of the line’s vector.

PySide6.QtCore.QLineF.
dy
()¶  Return type
float
Returns the vertical component of the line’s vector.

static
PySide6.QtCore.QLineF.
fromPolar
(length, angle)¶  Parameters
length – float
angle – float
 Return type
Returns a QLineF
with the given length
and angle
.
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.

PySide6.QtCore.QLineF.
intersects
(l)¶  Parameters
 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.

PySide6.QtCore.QLineF.
isNull
()¶  Return type
bool
Returns true
if the line does not have distinct start and end points; otherwise returns false
. The start and end points are considered distinct if qFuzzyCompare()
can distinguish them in at least one coordinate.
Note
Due to the use of fuzzy comparison, may return true
for lines whose length()
is not zero.
See also
qFuzzyCompare()
length()

PySide6.QtCore.QLineF.
length
()¶  Return type
float
Returns the length of the line.
See also

PySide6.QtCore.QLineF.
normalVector
()¶  Return type
Returns a line that is perpendicular to this line with the same starting point and length.
See also

PySide6.QtCore.QLineF.
__ne__
(d)¶  Parameters
 Return type
bool
Returns true
if the given line
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.

PySide6.QtCore.QLineF.
__mul__
(m)¶  Parameters
 Return type

PySide6.QtCore.QLineF.
__eq__
(d)¶  Parameters
 Return type
bool
Returns true
if the given line
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.

PySide6.QtCore.QLineF.
p1
()¶  Return type
Returns the line’s start point.

PySide6.QtCore.QLineF.
p2
()¶  Return type
Returns the line’s end point.

PySide6.QtCore.QLineF.
pointAt
(t)¶  Parameters
t – float
 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.

PySide6.QtCore.QLineF.
setAngle
(angle)¶  Parameters
angle – float
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

PySide6.QtCore.QLineF.
setLength
(len)¶  Parameters
len – float
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, unless length()
was previously zero, in which case no scaling is attempted. For lines with very short lengths (represented by denormal floatingpoint values), results may be imprecise.
See also

PySide6.QtCore.QLineF.
setLine
(x1, y1, x2, y2)¶  Parameters
x1 – float
y1 – float
x2 – float
y2 – float
Sets this line to the start in x1
, y1
and end in x2
, y2
.

PySide6.QtCore.QLineF.
setP1
(p1)¶  Parameters
Sets the starting point of this line to p1
.

PySide6.QtCore.QLineF.
setP2
(p2)¶  Parameters
Sets the end point of this line to p2
.

PySide6.QtCore.QLineF.
setPoints
(p1, p2)¶  Parameters
Sets the start point of this line to p1
and the end point of this line to p2
.

PySide6.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()

PySide6.QtCore.QLineF.
toTuple
()¶  Return type
object

PySide6.QtCore.QLineF.
translate
(p)¶  Parameters
Translates this line by the given offset
.

PySide6.QtCore.QLineF.
translate
(dx, dy)  Parameters
dx – float
dy – float
This is an overloaded function.
Translates this line the distance specified by dx
and dy
.

PySide6.QtCore.QLineF.
translated
(p)¶  Parameters
 Return type
Returns this line translated by the given offset
.

PySide6.QtCore.QLineF.
translated
(dx, dy)  Parameters
dx – float
dy – float
 Return type
This is an overloaded function.
Returns this line translated the distance specified by dx
and dy
.

PySide6.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, provided the line is nonnull.
See also

PySide6.QtCore.QLineF.
x1
()¶  Return type
float
Returns the xcoordinate of the line’s start point.
See also

PySide6.QtCore.QLineF.
x2
()¶  Return type
float
Returns the xcoordinate of the line’s end point.
See also

PySide6.QtCore.QLineF.
y1
()¶  Return type
float
Returns the ycoordinate of the line’s start point.
See also

PySide6.QtCore.QLineF.
y2
()¶  Return type
float
Returns the ycoordinate of the line’s end point.
See also
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