QLineF ¶

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

概要 ¶

函数 ¶

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 ()

静态函数 ¶

def fromPolar (length, angle)

详细描述 ¶

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() ，和 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.

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() 函数。

约束 ¶

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.

另请参阅

QLine QPolygonF QRectF

class QLineF ¶

QLineF(line)

QLineF(QLineF)

QLineF(pt1, pt2)

QLineF(x1, y1, x2, y2)

param QLineF

QLineF

param y1

qreal

param line

QLine

param y2

qreal

param pt1

QPointF

param x1

qreal

param pt2

QPointF

param x2

qreal

Constructs a null line.

构造 QLineF object from the given integer-based line .

另请参阅

toLine()

Constructs a line object that represents the line between p1 and p2 .

Constructs a line object that represents the line between ( x1 , y1 ) 和 ( x2 , y2 ).

PySide2.QtCore.QLineF. IntersectType ¶

使用 QLineF::IntersectionType 代替。

常量	描述
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__ ( ) ¶

返回类型: PyObject

PySide2.QtCore.QLineF. __repr__ ( ) ¶

返回类型: PyObject

PySide2.QtCore.QLineF. angle ( ) ¶

返回类型: 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 counter-clockwise from a point on the x-axis to the right of the origin (x > 0).

另请参阅

setAngle()

PySide2.QtCore.QLineF. angle ( l ) ¶

参数: l – QLineF
返回类型: qreal

注意

此函数被弃用。

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.

另请参阅

intersect()

PySide2.QtCore.QLineF. angleTo ( l ) ¶

参数: l – QLineF
返回类型: 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 (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.

另请参阅

intersect()

PySide2.QtCore.QLineF. center ( ) ¶

返回类型: QPointF

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

PySide2.QtCore.QLineF. dx ( ) ¶

返回类型: qreal

Returns the horizontal component of the line’s vector.

另请参阅

dy() pointAt()

PySide2.QtCore.QLineF. dy ( ) ¶

返回类型: qreal

Returns the vertical component of the line’s vector.

另请参阅

dx() pointAt()

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

参数

length – qreal
angle – qreal

返回类型

QLineF

返回 QLineF 采用给定 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 ) ¶

参数: l – QLineF
返回类型: (intersectType, intersectionPoint)

注意

此函数被弃用。

使用 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 ) ¶

参数

l – QLineF
intersectionPoint – QPointF

返回类型

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 ( ) ¶

返回类型: bool

返回 true if the line is not set up with valid start and end point; otherwise returns false .

PySide2.QtCore.QLineF. length ( ) ¶

返回类型: qreal

Returns the length of the line.

另请参阅

setLength()

PySide2.QtCore.QLineF. normalVector ( ) ¶

返回类型: QLineF

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

另请参阅

unitVector()

PySide2.QtCore.QLineF. __ne__ ( d ) ¶

参数: d – QLineF
返回类型: bool

返回 true 若给定 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 ) ¶

参数: m – QTransform
返回类型: QLineF

PySide2.QtCore.QLineF. __mul__ ( m ) ¶

参数: m – QMatrix
返回类型: QLineF

PySide2.QtCore.QLineF. __eq__ ( d ) ¶

参数: d – QLineF
返回类型: bool

返回 true 若给定 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 ( ) ¶

返回类型: QPointF

Returns the line’s start point.

另请参阅

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

PySide2.QtCore.QLineF. p2 ( ) ¶

返回类型: QPointF

Returns the line’s end point.

另请参阅

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

PySide2.QtCore.QLineF. pointAt ( t ) ¶

参数: t – qreal
返回类型: 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.

另请参阅

dx() dy()

PySide2.QtCore.QLineF. setAngle ( angle ) ¶

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

另请参阅

angle()

PySide2.QtCore.QLineF. setLength ( len ) ¶

参数: 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.

另请参阅

length() isNull()

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

参数

x1 – qreal
y1 – qreal
x2 – qreal
y2 – qreal

Sets this line to the start in x1 , y1 and end in x2 , y2 .

另请参阅

setP1() setP2() p1() p2()

PySide2.QtCore.QLineF. setP1 ( p1 ) ¶

参数: p1 – QPointF

Sets the starting point of this line to p1 .

另请参阅

setP2() p1()

PySide2.QtCore.QLineF. setP2 ( p2 ) ¶

参数: p2 – QPointF

Sets the end point of this line to p2 .

另请参阅

setP1() p2()

PySide2.QtCore.QLineF. setPoints ( p1 , p2 ) ¶

参数

p1 – QPointF
p2 – QPointF

Sets the start point of this line to p1 and the end point of this line to p2 .

另请参阅

setP1() setP2() p1() p2()

PySide2.QtCore.QLineF. toLine ( ) ¶

返回类型: QLine

Returns an integer based copy of this line.

Note that the returned line’s start and end points are rounded to the nearest integer.

另请参阅

QLineF()

PySide2.QtCore.QLineF. toTuple ( ) ¶

返回类型: PyObject

PySide2.QtCore.QLineF. translate ( p ) ¶

参数: p – QPointF

Translates this line by the given offset .

PySide2.QtCore.QLineF. translate ( dx , dy ) ¶

参数

dx – qreal
dy – qreal

这是重载函数。

Translates this line the distance specified by dx and dy .

PySide2.QtCore.QLineF. translated ( p ) ¶

参数: p – QPointF
返回类型: QLineF

Returns this line translated by the given offset .

PySide2.QtCore.QLineF. translated ( dx , dy ) ¶

参数

dx – qreal
dy – qreal

返回类型

QLineF

这是重载函数。

Returns this line translated the distance specified by dx and dy .

PySide2.QtCore.QLineF. unitVector ( ) ¶

返回类型: QLineF

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.

另请参阅

normalVector()

PySide2.QtCore.QLineF. x1 ( ) ¶

返回类型: qreal

Returns the x-coordinate of the line’s start point.

另请参阅

p1()

PySide2.QtCore.QLineF. x2 ( ) ¶

返回类型: qreal

Returns the x-coordinate of the line’s end point.

另请参阅

p2()

PySide2.QtCore.QLineF. y1 ( ) ¶

返回类型: qreal

Returns the y-coordinate of the line’s start point.

另请参阅

p1()

PySide2.QtCore.QLineF. y2 ( ) ¶

返回类型: qreal

Returns the y-coordinate of the line’s end point.

另请参阅

p2()

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QLineF ¶

概要 ¶

函数 ¶

静态函数 ¶

详细描述 ¶

约束 ¶