VR tech 411 : 6DoF, XYZ + YPR, position + orientation in 3space

I’ve spent so many cycles describing this gesturally to so many people, I’m considering getting this tattooed on my chest. To avert that,┬áhere is the diagram, liberally adapted, corrected, and upgraded from the Oculus Developer Guide:

We present to you, the standard coordinate 3-space system:

dSky-Oculus-XYZ-YPR position orientation diagram

POSITION is listed as a set of coordinates :

  • X is left / right
  • Y is up / down
  • Z is forward / back

ORIENTATION is represented as a quaternion* (later). Simply:

  • Pitch is leaning forward / back (X axis rotation)
  • Yaw is rotating left / right (Y axis rotation / compass orientation)
  • Roll is spinning clockwise / counterclockwise (Z axis rotation)

Now there, all clear. You’re welcome.


 

Further clarifications:

* a quaternion is a very special (and generally non-human readable) way of representing 3-dimensional orientation reference as a 4-dimensional number (X, Y, Z, W) in order to correct for strange behaviours encountered when rotating 3d objects.

* 6DoF is an acronym for “six degrees of freedom”. It is generally used in talking about input devices which allow a user to control position and orientation simultaneously, such as head trackers, playstation Moves, razer Hydras, Sixense STEMs, etc.