ENH: Set Seeds as conntainer objects

[blowekamp]

Best practices are to set member variables as object, and not repeat accessor methods in the interface of the owning object e.g. AddSeed, ClearSeed.

PR Checklist

• No API changes were made (or the changes have been approved)
• No major design changes were made (or the changes have been approved)
• Added test (or behavior not changed)
• Updated API documentation (or API not changed)
• Added license to new files (if any)
• Added Python wrapping to new files (if any) as described in ITK Software Guide Section 9.5
• Added ITK examples for all new major features (if any)

Refer to the ITK Software Guide for
further development details if necessary.

[blowekamp]

@jhlegarreta I was surprised to see SetSeed[12] marked as deprecated in some documentation changes made in #3866. d58bf56

These were the quick changes I made to have the seeds list behave like objects with setter/getters. Further investigation found other region growing filters with similar interfaces:

• ConfidenceConnectedImageFilter
• ConnectedThresholdImageFilter
• NeighborhoodConnectedImageFilter
• VectorConfidenceConnectedImageFilter
  They all have AddSeed, ClearSeeds, methods. Some have the "SetSeed" method marked as deprecated in the doxygen. I didn't see any with a get method for the seed list.

These classes seem to use std::vector to hold the seed lists. Perhaps performance was a reason for this approach? Modern C++ could do something like filter->SetSeedList(std::move(my_list)) where the data could be moved and not copied.

What can be done to improve the interface of these filters and make them more consistent?

[jhlegarreta]

Really sorry @blowekamp, looks like I was confused by the docstring in the implementation file, which documented the method as being deprecated:
d58bf56#diff-9daea1a5d3498baf38e16ef9fd06da89d2f898c4b599a7eb287a76fc3a720accL105
d58bf56#diff-9daea1a5d3498baf38e16ef9fd06da89d2f898c4b599a7eb287a76fc3a720accL137

But after investigation, I now see that the documentation was not updated and the passage left inadvertently in
c005b54

So please, go ahead and update the documentation.

If possible, can the methods be tested, please?

[hjmjohnson]

Rebased onto current main (was ~7.5k commits behind / conflicting) and addressed @jhlegarreta's review: deprecation docstrings now point to SetSeeds2, and the test exercises the new SetSeeds/GetSeeds container accessors. Built ITKRegionGrowingTestDriver and ran both itkIsolatedConnectedImageFilterTest cases locally — green. Pushed to this branch (maintainer edit).

Details

• Conflict resolution: main wrapped GetSeeds1/2 in @ITKStartGrouping/@ITKEndGrouping; kept the itkSetMacro/itkGetConstReferenceMacro block inside those markers.
• Test: round-trips the populated seed containers through ClearSeeds → SetSeeds1/2 → GetSeeds1/2, leaving the filter state unchanged so the existing baseline comparison is unaffected.
• pre-commit run --all-files clean on the pushed tip.

[hjmjohnson]

@blowekamp I've rebased your initial work and addressed the comment to add a test. I left this as a draft and kept you as the author.

[hjmjohnson]

I'm good with this as is, or with more aggressive deprecation warnings.

[hjmjohnson]

@blowekamp Greptile suggestions look like appropriate minor improvements.

[hjmjohnson]

/azp run ITK.Linux

[hjmjohnson]

/azp run ITK.Linux.Python

[hjmjohnson]

/azp run ITK.macOS.Python