Jerome Duriez said: (by the date of Tue, 12 Feb 2008 16:55:13 +0100) > Hello everybody. I am focusing about the "RotationEngine" (in > pkg/common/Engine/DeusExMachina) and trying to understand well what it > does, so I have for instance one simple question : > > - which is the purpose of the line > "/rb->se3.orientation.ToAxisAngle(ax,an);/" ? I think I understand what > it does : it affects to the 3-real vector "/ax/" and the real "/an"/
It does not affect ax and an. The se3.orientation is built from axis,angle. This command calculates 3D orientation (rotation) from two arguments - the axis of rotation, and the angle of rotation around this axis. > (both declared few lines above) respectively the axis and angle of the > rotation corresponding to the quaternion "/orientation/". > But why ? > These "/an/" and "/ax/" seem indeed never to be used after that... So axis, angle are not used after that, because we don't need them anymore - we are using se3.orientation built from them. To understand this better have a look at page 145 of http://janek.kozicki.pl/phdthesis/kozicki_2007_PhD.pdf best regards -- Janek Kozicki | _______________________________________________ Yade-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/yade-users
