[Insight-users] BSplineDeformableTransform -- Region Setting

[Bing Jian]

Hi, Luis,

   I am reading the source code of BSplineDeformableTransform class
and have following questions regarding the comments in header file
itkBsplineDeformableTransform.h and the test program in ...test.cxx.

   The first thing is about the region setting.

 In example usage at the beginning of the header file, we see

   ...
   transform->SetGridRegion( region );
   ...
   // NB: the region must be set first before setting the parameters

 and in Testing/Code/Common/itkBSplineDeformableTransformTest.cxx,
the corresponding code is listed as below:

  /**
   * Define the deformable grid region, spacing and origin
   */
  typedef TransformType::RegionType RegionType;
  RegionType region;
  RegionType::SizeType   size;
  size.Fill( 10 );
  region.SetSize( size );
  std::cout << region << std::endl;

  My question is what's the meaning of this region. Does it mean
we have 10^N grid/control points where N is the image dimension?
Is this number 10^N the one represented by N-D in comments?

And then we have

  typedef TransformType::SpacingType SpacingType;
  SpacingType spacing;
  spacing.Fill( 2.0 );

  typedef TransformType::OriginType OriginType;
  OriginType origin;
  origin.Fill( 0.0 );

  transform->SetGridSpacing( spacing );
  transform->SetGridOrigin( origin );
  transform->SetGridRegion( region );

in this case, how are those control points selected? Could you
please enumerate a few points with index?

  Thanks!

 (to be continued :-)


-- 
Best wishes,
Bing Jian
bjian at cise . ufl . edu