[Interest] Plane rotations

[Sean Harmer]

Yes, just use the dot product.

Sean

On Wednesday 05 April 2017 14:59:48 Igor Mironchik wrote:
> Hi,
> 
> I Googled it and found:
> 
> The cos of angle between vectors is:
> |(ax*bx + ay*by + az*bz)
> 
> -------------------------------------------------------- sqrt(ax*ax +
> ay*ay + az*az) * sqrt(bx*bx + by*by + bz*bz)|
> 
> 05.04.2017 14:52, Igor Mironchik пишет:
> > 05.04.2017 14:45, Igor Mironchik пишет:
> >> Hi,
> >> 
> >> 05.04.2017 14:29, Paolo Angelelli пишет:
> >>> Just cross N and M to get the vector around which to rotate.
> >>> 
> >>> Then use a QQuaternion to set the rotation in the Qt3DCore::QTransform,
> >>> and construct it with fromAxisAndAngle(const QVector3D &axis, float
> >>> angle)
> >> 
> >> Ok, I can rotate around the right axis. But what angle should I rotate?
> > 
> > This is my question.
> > 
> >> And how can I calculate new normal to the rotated plane?
> > 
> > I already know it...
> > 
> > I just need to know what angle should I rotate.
> > 
> >>> On Wed, 5 Apr 2017 14:18:56 +0300
> >>> 
> >>> Igor Mironchik <igor.mironchik at gmail.com> wrote:
> >>>> Hello,
> >>>> 
> >>>> Let's say I have two vectors - N (normal vector to plane P1) and M
> >>>> (normal vector to plane P2).
> >>>> 
> >>>> How to calculate x, y, z axis rotations angles for plane P2 to make
> >>>> plane P2 parallel to P1?
> >>>> 
> >>>> How to calculate x, y, z axis rotations angles for plane P2 to
> >>>> rotate it
> >>>> around vector N?
> >>>> 
> >>>> Thank you.
> >>>> 
> >>>> And what is the measurement of angle in rotationX() of
> >>>> Qt3DCore::QTransform?
> >>>> 
> >>>> I need to calculate angles in this units.
> >>>> 
> >>>> _______________________________________________
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> >>>> Interest at qt-project.org
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> >>> 
> >>> _______________________________________________
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> >>> http://lists.qt-project.org/mailman/listinfo/interest

-- 
Dr Sean Harmer | sean.harmer at kdab.com | Managing Director UK
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