class QVector2D#

The QVector2D class represents a vector or vertex in 2D space. More…

New in version 4.6.

Synopsis#

Methods#

def __init__()
def __reduce__()
def __repr__()
def distanceToLine()
def distanceToPoint()
def isNull()
def length()
def lengthSquared()
def normalize()
def normalized()
def __ne__()
def __mul__()
def __imul__()
def __add__()
def __iadd__()
def __sub__()
def __isub__()
def __div__()
def operator/=()
def __eq__()
def operator[]()
def setX()
def setY()
def toPoint()
def toPointF()
def toTuple()
def toVector3D()
def toVector4D()
def x()
def y()

Static functions#

def dotProduct()

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#

Vectors are one of the main building blocks of 2D representation and drawing. They consist of two finite floating-point coordinates, traditionally called x and y.

The QVector2D class can also be used to represent vertices in 2D space. We therefore do not need to provide a separate vertex class.

See also

QVector3D QVector4D QQuaternion

__init__(point)#

Parameters:: point – QPoint

Constructs a vector with x and y coordinates from a 2D point.

__init__()

Constructs a null vector, i.e. with coordinates (0, 0).

__init__(xpos, ypos)

Parameters:

xpos – float
ypos – float

Constructs a vector with coordinates (xpos, ypos). Both coordinates must be finite.

__init__(vector)

Parameters:: vector – QVector4D

Constructs a vector with x and y coordinates from a 3D vector. The z and w coordinates of vector are dropped.

See also

toVector4D()

__init__(point)

Parameters:: point – QPointF

Constructs a vector with x and y coordinates from a 2D point.

__init__(vector)

Parameters:: vector – QVector3D

Constructs a vector with x and y coordinates from a 3D vector. The z coordinate of vector is dropped.

See also

toVector3D()

__reduce__()#

Return type:: object

__repr__()#

Return type:: object

distanceToLine(point, direction)#

Parameters:

point – QVector2D
direction – QVector2D

Return type:

float

Returns the distance that this vertex is from a line defined by point and the unit vector direction.

If direction is a null vector, then it does not define a line. In that case, the distance from point to this vertex is returned.

See also

distanceToPoint()

distanceToPoint(point)#

Parameters:: point – QVector2D
Return type:: float

Returns the distance from this vertex to a point defined by the vertex point.

See also

distanceToLine()

static dotProduct(v1, v2)#

Parameters:

v1 – QVector2D
v2 – QVector2D

Return type:

float

Returns the dot product of v1 and v2.

isNull()#

Return type:: bool

Returns true if the x and y coordinates are set to 0.0, otherwise returns false.

length()#

Return type:: float

Returns the length of the vector from the origin.

See also

lengthSquared() normalized()

lengthSquared()#

Return type:: float

Returns the squared length of the vector from the origin. This is equivalent to the dot product of the vector with itself.

See also

length() dotProduct()

normalize()#

Normalizes the current vector in place. Nothing happens if this vector is a null vector or the length of the vector is very close to 1.

See also

length() normalized()

normalized()#

Return type:: QVector2D

Returns the normalized unit vector form of this vector.

If this vector is null, then a null vector is returned. If the length of the vector is very close to 1, then the vector will be returned as-is. Otherwise the normalized form of the vector of length 1 will be returned.

See also

length() normalize()

__ne__(v2)#

Parameters:: v2 – QVector2D
Return type:: bool

Returns true if v1 is not equal to v2; otherwise returns false. This operator uses an exact floating-point comparison.

__mul__(v2)#

Parameters:: v2 – QVector2D
Return type:: QVector2D

Returns the QVector2D object formed by multiplying each component of v1 by the corresponding component of v2.

Note

This is not a cross product of v1 and v2 in any sense. (Its components add up to the dot product of v1 and v2.)