[Insight-developers] Removing PhysicalPoitnToIndex() from itkImage ?

[Luis Ibanez]

Hi,

itkImage has a two methods for converting between Indexes and Points
and two other methods for converting between ContinuousIndexes and Points
These methods construct (and cache) a couple of AffineTransforms.  

This limits the use to the geometries that can be represented by Affine
transforms.

I could be better to support this by a helper class external to the image.  
This class would:

1) get the Transform (of any kind) from the image,
2) receive an Index, (to be mapped to a physical point)
3) cast this Index to an itkPoint
4) map the Point through the Transform
5) return the resulting point.

This is basically what the method:

      TransformIndexToPhysicalPoint()

is doing.

Similar methods:

   TransformPhysicalPointToContinuousIndex()
   TransformPhysicalPointToIndex()
   TransformContinuousIndexToPhysicalPoint()

perform the other combinations and could then be
replaced by equivalent helper classes.

Does anybody see a disadvantage in outsourcing
these conversions from the itkImage    ?

   Luis