- class QGraphicsRotation#
The
QGraphicsRotation
class provides a rotation transformation around a given axis. More…New in version 4.6.
Synopsis#
Properties#
Methods#
def
__init__()
def
angle()
def
axis()
def
origin()
def
setAngle()
def
setAxis()
def
setOrigin()
Signals#
def
angleChanged()
def
axisChanged()
def
originChanged()
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#
You can provide the desired axis by assigning a QVector3D to the axis property or by passing a member if Qt::Axis to the
setAxis
convenience function. By default the axis is (0, 0, 1) i.e., rotation around the Z axis.The angle property, which is provided by
QGraphicsRotation
, now describes the number of degrees to rotate around this axis.QGraphicsRotation
provides certain parameters to help control how the rotation should be applied.The origin is the point that the item is rotated around (i.e., it stays fixed relative to the parent as the rest of the item is rotated). By default the origin is QPointF(0, 0).
The angle property provides the number of degrees to rotate the item clockwise around the origin. This value also be negative, indicating a counter-clockwise rotation. For animation purposes it may also be useful to provide rotation angles exceeding (-360, 360) degrees, for instance to animate how an item rotates several times.
Note: the final rotation is the combined effect of a rotation in 3D space followed by a projection back to 2D. If several rotations are performed in succession, they will not behave as expected unless they were all around the Z axis.
See also
Note
Properties can be used directly when
from __feature__ import true_property
is used or via accessor functions otherwise.- property angleᅟ: float#
This property holds the angle for clockwise rotation, in degrees..
The angle can be any real number; the default value is 0.0. A value of 180 will rotate 180 degrees, clockwise. If you provide a negative number, the item will be rotated counter-clockwise. Normally the rotation angle will be in the range (-360, 360), but you can also provide numbers outside of this range (e.g., a angle of 370 degrees gives the same result as 10 degrees). Setting the angle to NaN results in no rotation.
See also
- Access functions:
Signal
angleChanged()
This property holds a rotation axis, specified by a vector in 3D space..
This can be any axis in 3D space. By default the axis is (0, 0, 1), which is aligned with the Z axis. If you provide another axis,
QGraphicsRotation
will provide a transformation that rotates around this axis. For example, if you would like to rotate an item around its X axis, you could pass (1, 0, 0) as the axis.See also
- Access functions:
Signal
axisChanged()
This property holds the origin of the rotation in 3D space..
All rotations will be done relative to this point (i.e., this point will stay fixed, relative to the parent, when the item is rotated).
See also
- Access functions:
Signal
originChanged()
Constructs a new
QGraphicsRotation
with the givenparent
.- angle()#
- Return type:
float
See also
Getter of property
angleᅟ
.- angleChanged()#
This signal is emitted whenever the angle has changed.
See also
Notification signal of property
angleᅟ
.Getter of property
axisᅟ
.- axisChanged()#
This signal is emitted whenever the axis of the object changes.
See also
Notification signal of property
axisᅟ
.- origin()#
- Return type:
See also
Getter of property
originᅟ
.- originChanged()#
This signal is emitted whenever the origin has changed.
See also
Notification signal of property
originᅟ
.Setter of property
angleᅟ
.Convenience function to set the axis to
axis
.Note: the Qt::YAxis rotation for QTransform is inverted from the correct mathematical rotation in 3D space. The
QGraphicsRotation
class implements a correct mathematical rotation. The following two sequences of code will perform the same transformation:QTransform t; t.rotate(45, Qt::YAxis); QGraphicsRotation r; r.setAxis(Qt::YAxis); r.setAngle(-45);
Setter of property
axisᅟ
.Setter of property
originᅟ
.