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Units in Optitrack / Motive

Posted: Wed May 15, 2013 10:40 am
by circassia
Hi,

i would like to ask, in which units rotations are passed through the data-stream? Unit Quaternions? Are there detailled informaiton somewhere?

thank you very much!

circassia

Re: Units in Optitrack / Motive

Posted: Wed May 15, 2013 12:05 pm
by NaturalPoint-Dustin
Hi Circassia,

Our system matches this:

http://www.euclideanspace.com/maths/geo ... /index.htm


Let me know if this answers all of your questions.

Best Regards,

Re: Units in Optitrack / Motive

Posted: Wed May 15, 2013 12:40 pm
by circassia
:) indeed its helpfull, but thats too detailed. Maybe if you can answer me if the data streamed is in unit quaternions? already normalized?

thanks

Re: Units in Optitrack / Motive

Posted: Wed May 15, 2013 1:42 pm
by beckdo
It's important to clarify what mechanism of data streaming out of the software you're referring to. Our software essentially uses quaternions throughout internally. We only convert to Euler angles if the streaming protocol uses them. Whenever possible we stream quats or also stream quats. We can provide conversion code if need be to get back to our quats from Eulers if quats are unavailable.

Re: Units in Optitrack / Motive

Posted: Thu May 16, 2013 3:19 am
by circassia
1) No no, we need quaternionans as we feed them back into our 3D-Engine, the question is, if they are unit quaternions (length = 1)

2) Furthermore the streamed data are sent in milimeters from motive ?

thanks a lot!