Andreea
try:
double angle = Math.atan(mat.m10/mat.m00);
where mat is your matrix3f
might need to faff about with signs
Answer easy to find by manually multiplying a vector perpedicular to z axis
([1,0,0] will do nicely) by the matrix and seeing what happens when the
resulting vector is projected onto xy plane (z=0)
cheers,
David Turland
----- Original Message -----
From: Pondrom, Pierre L <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, March 23, 2000 11:16 PM
Subject: Re: [JAVA3D] rotational component
> It depends on the order in which the matrix was built.
> You can use atan2() and asin() on 2 elements of the matrix
> and back out the angle used, but you have to know
> how the matrix was built in order to pick the right elements.
>
>
>
> > ----------
> > From: Andreea Francu[SMTP:[EMAIL PROTECTED]]
> > Reply To: Discussion list for Java 3D API
> > Sent: Thursday, March 23, 2000 10:48 AM
> > To: [EMAIL PROTECTED]
> > Subject: [JAVA3D] rotational component
> >
> > I have a Matrix3f object and I need to retrive the rotational component
> > around the z axis. Any idea how to do that?
> >
> > Thanks,
> >
> > Andreea
> >
> >
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>
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