QLineF¶

The QLineF class provides a two-dimensional vector using floating point precision. More…

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 intersects (l, intersectionPoint)
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 ()

Static functions¶

def fromPolar (length, angle)

Detailed Description¶

A QLineF describes a finite length line (or line segment) on a two-dimensional 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.

See also

QLine QPolygonF QRectF

class PySide2.QtCore.QLineF¶

PySide2.QtCore.QLineF(line)

PySide2.QtCore.QLineF(QLineF)

PySide2.QtCore.QLineF(pt1, pt2)

PySide2.QtCore.QLineF(x1, y1, x2, y2)

param QLineF:

PySide2.QtCore.QLineF

param y1:

float

param line:

PySide2.QtCore.QLine

param y2:

float

param pt1:

PySide2.QtCore.QPointF

param x1:

float

param pt2:

PySide2.QtCore.QPointF

param x2:

float

Constructs a null line.

Construct a QLineF object from the given integer-based line .

See also

toLine()

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 ).

PySide2.QtCore.QLineF.IntersectType¶

Use QLineF::IntersectionType instead.

Constant	Description
QLineF.NoIntersection	Lines do not intersect.
QLineF.UnboundedIntersection	Lines intersect, but not within the range defined by their lengths.
QLineF.BoundedIntersection	Lnes intersect within the range defined by their lengths.

PySide2.QtCore.QLineF.__reduce__()¶

Return type:: object

PySide2.QtCore.QLineF.__repr__()¶

Return type:: object

PySide2.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 counter-clockwise from a point on the x-axis to the right of the origin (x > 0).

See also

setAngle()

PySide2.QtCore.QLineF.angle(l)

Parameters:: l – PySide2.QtCore.QLineF
Return type:: float

Note

This function is deprecated.

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 (see UnboundedIntersection ).

qlinef-angle-identicaldirection1

qlinef-angle-oppositedirection2

When the lines are parallel, this function returns 0 if they have the same direction; otherwise it returns 180.

See also

intersect()

PySide2.QtCore.QLineF.angleTo(l)¶

Parameters:: l – PySide2.QtCore.QLineF
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 counter-clockwise.

See also

intersect()

PySide2.QtCore.QLineF.center()¶

Return type:: PySide2.QtCore.QPointF

Returns the center point of this line. This is equivalent to 0.5 * p1() + 0.5 * p2() .

PySide2.QtCore.QLineF.dx()¶

Return type:: float

Returns the horizontal component of the line’s vector.

See also

dy() pointAt()

PySide2.QtCore.QLineF.dy()¶

Return type:: float

Returns the vertical component of the line’s vector.

See also

dx() pointAt()

static PySide2.QtCore.QLineF.fromPolar(length, angle)¶

Parameters:

length – float
angle – float

Return type:

PySide2.QtCore.QLineF

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 counter-clockwise while negative values mean the clockwise direction. Zero degrees is at the 3 o’clock position.

PySide2.QtCore.QLineF.intersect(l)¶

Parameters:: l – PySide2.QtCore.QLineF
Return type:: (intersectType, intersectionPoint)

Note

This function is deprecated.

Use intersects() instead

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.intersects(l, intersectionPoint)¶

Parameters:

l – PySide2.QtCore.QLineF
intersectionPoint – PySide2.QtCore.QPointF

Return type:

IntersectType

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 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()

PySide2.QtCore.QLineF.length()¶

Return type:: float

Returns the length of the line.

See also

setLength() isNull()

PySide2.QtCore.QLineF.normalVector()¶

Return type:: PySide2.QtCore.QLineF

Returns a line that is perpendicular to this line with the same starting point and length.

See also

unitVector()

PySide2.QtCore.QLineF.__ne__(d)¶

Parameters:: d – PySide2.QtCore.QLineF
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.

PySide2.QtCore.QLineF.__mul__(m)¶

Parameters:: m – PySide2.QtGui.QTransform
Return type:: PySide2.QtCore.QLineF

PySide2.QtCore.QLineF.__mul__(m)

Parameters:: m – PySide2.QtGui.QMatrix
Return type:: PySide2.QtCore.QLineF

PySide2.QtCore.QLineF.__eq__(d)¶

Parameters:: d – PySide2.QtCore.QLineF
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.

PySide2.QtCore.QLineF.p1()¶

Return type:: PySide2.QtCore.QPointF

Returns the line’s start point.

See also

setP1() x1() y1() p2()

PySide2.QtCore.QLineF.p2()¶

Return type:: PySide2.QtCore.QPointF

Returns the line’s end point.

See also

setP2() x2() y2() p1()

PySide2.QtCore.QLineF.pointAt(t)¶

Parameters:: t – float
Return type:: PySide2.QtCore.QPointF

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.

See also

dx() dy()

PySide2.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 counter-clockwise while negative values mean the clockwise direction. Zero degrees is at the 3 o’clock position.

See also

angle()

PySide2.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 floating-point values), results may be imprecise.

See also

length() unitVector()

PySide2.QtCore.QLineF.setLine(x1, y1, x2, y2)¶