[ODE] getUniversalAngle and dRFrom2Axes
Dirk Gregorius
dirk at dirkgregorius.de
Tue Sep 27 20:12:12 MST 2005
(1)
From the funtion source code:
joint.cpp - getUniversalAngle()
// It should be possible to get both angles without explicitly
// constructing the rotation matrix of the cross. Basically,
// orientation of the cross about axis1 comes from body 2,
// about axis 2 comes from body 1, and the perpendicular
// axis can come from the two bodies somehow. (We don't really
// want to assume it's 90 degrees, because in general the
// constraints won't be perfectly satisfied, or even very well
// satisfied.)
//
// However, we'd need a version of getHingeAngleFromRElativeQuat()
// that CAN handle when its relative quat is rotated along a direction
// other than the given axis. What I have here works,
// although it's probably much slower than need be.
Did anybody figure this out? Is there better way to extract the angles?
The same question for the Hinge Joint - any better methods to extract
the current hinge angle?
(2)
dRFrom2Axes( R, ax, ay, az, bx, by, bz )
What is this function supposed to return. The matrix that
rotates a into b or vice versa? Any other form of rotation?
Regards,
-Dirk
More information about the ODE
mailing list