class QVector2D#

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

New in version 4.6.

Synopsis#

Methods#

Static functions#

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.

__init__(point)#
Parameters:

pointQPoint

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:

vectorQVector4D

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:

pointQPointF

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

__init__(vector)
Parameters:

vectorQVector3D

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:
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.

distanceToPoint(point)#
Parameters:

pointQVector2D

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:
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.

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.

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.

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.

__ne__(v2)#
Parameters:

v2QVector2D

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:

v2QVector2D

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.)

See also

operator*=()

__mul__(factor)
Parameters:

factor – float

Return type:

QVector2D

Returns a copy of the given vector, multiplied by the given finite factor.

See also

operator*=()

__mul__(factor)
Parameters:

factor – float

Return type:

QVector2D

Returns a copy of the given vector, multiplied by the given finite factor.

See also

operator*=()

__imul__(factor)#
Parameters:

factor – float

Return type:

QVector2D

Multiplies this vector’s coordinates by the given finite factor and returns a reference to this vector.

See also

operator/=() operator*()

__imul__(vector)
Parameters:

vectorQVector2D

Return type:

QVector2D

Multiplies each component of this vector by the corresponding component of vector and returns a reference to this vector.

Note

This is not a cross product of this vector with vector. (Its components add up to the dot product of this vector and vector.)

See also

operator/=() operator*()

__add__(v2)#
Parameters:

v2QVector2D

Return type:

QVector2D

Returns a QVector2D object that is the sum of the given vectors, v1 and v2; each component is added separately.

See also

operator+=()

__iadd__(vector)#
Parameters:

vectorQVector2D

Return type:

QVector2D

Adds the given vector to this vector and returns a reference to this vector.

See also

operator-=()

__sub__()#
Return type:

QVector2D

This is an overloaded function.

Returns a QVector2D object that is formed by changing the sign of each component of the given vector.

Equivalent to QVector2D(0,0) - vector.

__sub__(v2)
Parameters:

v2QVector2D

Return type:

QVector2D

Returns a QVector2D object that is formed by subtracting v2 from v1; each component is subtracted separately.

See also

operator-=()

__isub__(vector)#
Parameters:

vectorQVector2D

Return type:

QVector2D

Subtracts the given vector from this vector and returns a reference to this vector.

See also

operator+=()

__div__(divisor)#
Parameters:

divisorQVector2D

Return type:

QVector2D

Returns the QVector2D object formed by dividing each component of the given vector by the corresponding component of the given divisor.

The divisor must have no component that is either zero or NaN.

See also

operator/=()

__div__(divisor)
Parameters:

divisor – float

Return type:

QVector2D

Returns the QVector2D object formed by dividing each component of the given vector by the given divisor.

The divisor must not be either zero or NaN.

See also

operator/=()

operator/=(vector)
Parameters:

vectorQVector2D

Return type:

QVector2D

Divides each component of this vector by the corresponding component of vector and returns a reference to this vector.

The vector must have no component that is either zero or NaN.

See also

operator*=() operator/()

operator/=(divisor)
Parameters:

divisor – float

Return type:

QVector2D

Divides this vector’s coordinates by the given divisor and returns a reference to this vector. The divisor must not be either zero or NaN.

See also

operator*=()

__eq__(v2)#
Parameters:

v2QVector2D

Return type:

bool

Returns true if v1 is equal to v2; otherwise returns false. This operator uses an exact floating-point comparison.

operator(i)#
Parameters:

i – int

Return type:

float

Returns the component of the vector at index position i.

i must be a valid index position in the vector (i.e., 0 <= i < 2).

setX(x)#
Parameters:

x – float

Sets the x coordinate of this point to the given finite x coordinate.

See also

x() setY()

setY(y)#
Parameters:

y – float

Sets the y coordinate of this point to the given finite y coordinate.

See also

y() setX()

toPoint()#
Return type:

QPoint

Returns the QPoint form of this 2D vector. Each coordinate is rounded to the nearest integer.

toPointF()#
Return type:

QPointF

Returns the QPointF form of this 2D vector.

toTuple()#
Return type:

object

toVector3D()#
Return type:

QVector3D

Returns the 3D form of this 2D vector, with the z coordinate set to zero.

toVector4D()#
Return type:

QVector4D

Returns the 4D form of this 2D vector, with the z and w coordinates set to zero.

x()#
Return type:

float

Returns the x coordinate of this point.

See also

setX() y()

y()#
Return type:

float

Returns the y coordinate of this point.

See also

setY() x()