Quaternions

[farshizzo]

The meaning of the x,y,z,w components of a quaternion are similar to the meaning of axis-angle components. the [x,y,z] values represent the axis of rotation. The amount of rotation about that axis in radians is, 2 * acos(w). Keep in mind that Vizard uses a left-handed coordinate system.

All the plugins should return quaternions in the same order (x,y,z,w). I'm assuming most devices will return normalized quaternions as well, but I'm not 100% sure about that.