void
CreateBasis(const avtVector &N, const avtVector &UP,
avtVector &u, avtVector &v, avtVector&w)
{
w = N.normalized();
u = (UP % w).normalized();
if (u.norm() == 0)
{
avtVector origin(0., 0., 0.);
avtVector y(0., 1., 0.);
avtMatrix R; R.MakeRBT(origin, N, UP);
y = R * y;
u = (y % w).normalized();
}
v = (w % u).normalized();
}
// ****************************************************************************
// Method: avtTrackball::SetConstrainAxis
//
// Purpose:
// Set an axis to constrain to.
//
// Arguments:
// v the axis
//
// Programmer: Jeremy Meredith
// Creation: October 9, 2001
//
// ****************************************************************************
void
avtTrackball::SetConstrainAxis(const avtVector &v)
{
constrainAxis = v.normalized();
constrain = true;
}
