id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
461	Euler angles don't have convention specified	Paul Price	Paul Price	"Rotations, as well as the quaternion representation of a rotation, depends on
the convention adopted, and there is no clear information in the SDRS or ADD
that directly specifies what convention we adopt.

Figure 1 on p23 of the ADD (PSDC-430-006-011) seems to specify a left-handed
system with a zyz convention, but most of the information available on the web
are for right-handed systems.  For example, see
http://www.euclideanspace.com/maths/geometry/rotations/euler/index.htm , where I
think the ""NASA Standard Aerospace"" is a zyz convention in a right-handed
system, but the matrices don't match the ""y convention"" at Mathworld
http://mathworld.wolfram.com/EulerAngles.html

Since this is an area abounding in confusion, we need to be be very clear about
the conventions we adopt and specify all relevant formulae (e.g., it is not
immediately clear how to convert the Euler angles fed into psSphereRotAlloc into
the quaternion representation).  We also need to be careful that we are
supplying the correct formulae, since there are so many.

Perhaps Ed could provide the appropriate formulae?"	defect	closed	high		PSLib SDRS	unspecified	normal	fixed		robert.desonia@… David.Robbins@…