openalea.phenomenal.calibration.transformations.Arcball

class openalea.phenomenal.calibration.transformations.Arcball(initial=None)

Bases: object

Virtual Trackball Control.

>>> ball = Arcball()
>>> ball = Arcball(initial=numpy.identity(4))
>>> ball.place([320, 320], 320)
>>> ball.down([500, 250])
>>> ball.drag([475, 275])
>>> R = ball.matrix()
>>> numpy.allclose(numpy.sum(R), 3.90583455)
True
>>> ball = Arcball(initial=[1, 0, 0, 0])
>>> ball.place([320, 320], 320)
>>> ball.setaxes([1, 1, 0], [-1, 1, 0])
>>> ball.constrain = True
>>> ball.down([400, 200])
>>> ball.drag([200, 400])
>>> R = ball.matrix()
>>> numpy.allclose(numpy.sum(R), 0.2055924)
True
>>> ball.next()

__init__(initial=None)

Initialize virtual trackball control.

initial : quaternion or rotation matrix

Methods

__init__([initial])	Initialize virtual trackball control.
down(point)	Set initial cursor window coordinates and pick constrain-axis.
drag(point)	Update current cursor window coordinates.
matrix()	Return homogeneous rotation matrix.
next([acceleration])	Continue rotation in direction of last drag.
place(center, radius)	Place Arcball, e.g. when window size changes.
setaxes(*axes)	Set axes to constrain rotations.

Attributes

constrain

Return state of constrain to axis mode.

property constrain

Return state of constrain to axis mode.

down(point)

Set initial cursor window coordinates and pick constrain-axis.

drag(point)

Update current cursor window coordinates.

matrix()

Return homogeneous rotation matrix.

next(acceleration=0.0)

Continue rotation in direction of last drag.

place(center, radius)

Place Arcball, e.g. when window size changes.

centersequence[2]

Window coordinates of trackball center.

radiusfloat

Radius of trackball in window coordinates.

setaxes(*axes)

Set axes to constrain rotations.