[Insight-developers] Status on Transform changes

[Luis Ibanez]

Well the dashboard is a little redish :-)
but that's getting better.

Transforms are now deriving from itkObject,
so the New() and smart pointers are used.

There is a new ScaleTransform, that keeps
an array with scale factors, it multiplies
points and vector components, and divides
covariant vector components (e.g. Gradients)

GradientDescent and RegularStepGradientDescent
are using it now. It is useful to normalize
the range of parameters representing rotations
and those representing translations.

NOTE: Gradient Descent was multiplying the
gradient by the factors instead of dividing
it, and in general seems that the scale is
being used for the gradients but not for the
values themselves.  ...Something to check.


itk*RegistrationTransforms are not used anymore,
Transforms now provide : SetParameters() and
GetJacobian(). The parameter scaling is not done
by transforms but by the optimizers using the
ScaleTransform.

itkImageToImage*Registration  are still on
progress


Luis