[Insight-developers] Covariant vectors

[Stephen R. Aylward]

Hi,

Some of the transforms (all of the ones derived from rigid2DTransform, 
versorTransform, and others) are transforming covariant-vectors as if 
they were vectors.  That is, the covariant-vectors are being transformed 
via multiplication by the matrix instead of multiplication by the 
transpose of the inverse matrix.  See the clear description at
http://www.worldserver.com/turk/computergraphics/NormalTransformations.pdf

To fix this bug requires changes to select tests and transform classes. 
  I assume it is okay for me to make these changes since it is truly a 
bug in ITK.  Let me know if you don't agree...

I've completed most of these changes as part of the standardization of 
the matrix-offset-based transforms.

Thanks,
Stephen

-- 
===========================================================
Dr. Stephen R. Aylward
Associate Professor of Radiology
Adjunct Associate Professor of Computer Science and Surgery
http://caddlab.rad.unc.edu
aylward at unc.edu
(919) 966-9695