fix(labelmap): apply styles based on active segment index

[stada526]

Context

While rendering, segment styles such as opacity, fill etc do not consider active segment based on its index.
This issue was partly fixed via #1833, but only for Contour, so I’ve made some updates for Labelmap.

Changes & Results

Active segmentationId along with the segmentIndex should determine whether a segment is active or not.

2025-02-19.10.21.58.mov

Testing

Checklist

PR

• My Pull Request title is descriptive, accurate and follows the
  semantic-release format and guidelines.

Code

• [] My code has been well-documented (function documentation, inline comments,
  etc.)

• [] I have run the yarn build:update-api to update the API documentation, and have
  committed the changes to this PR. (Read more here https://www.cornerstonejs.org/docs/contribute/update-api)

Public Documentation Updates

• [] The documentation page has been updated as necessary for any public API
  additions or removals.

Tested Environment

• [] "OS:
• [] "Node version:
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[minimal-scouser]

yeah i missed raising this change for labelmaps. good spot.

[sedghi]

I explained in the other PR why we can't merge this, you can use perSegment config for this purpose

[stada526]

Hi @sedghi ,

I tried using segmentIndex in the setStyle function, but it didn’t seem to work properly.
I added the following code at the end of tools/examples/labelmapSegmentLocking/index.ts, but the opacity of each segment didn’t change when switching the active segment index, as shown in the attached video.

segmentation.config.style.setStyle(
  {
    type: csToolsEnums.SegmentationRepresentations.Labelmap,
    segmentationId,
    segmentIndex: 1,
  },
  {
    fillAlpha: 1,
    fillAlphaInactive: 0,
  }
);
segmentation.config.style.setStyle(
  {
    type: csToolsEnums.SegmentationRepresentations.Labelmap,
    segmentationId,
    segmentIndex: 2,
  },
  {
    fillAlpha: 1,
    fillAlphaInactive: 0,
  }
);

I'd appreciate it if you could clarify what I might be missing.

2025-02-24.12.27.29.mov

[sedghi]

@stada526 I will get back to this next week, busy with cs3d 3.0 right now

[minimal-scouser]

@stada526 per the office hour discussion, the active/inactive setting is supposed to be interpreted as the segmentation level change not the segment level change.

atleast that's what i could gather.

[stada526]

@sedghi
Thank you for letting me know! It's exciting to hear that Cornerstone.js v3 is coming - looking forward to it. Appreciate all the great work you do!

@minimal-scouser
Thank you for sharing this information! Would it be possible to add functionality that allows the active/inactive settings to be applied at the segment level?
My original intention with the feature request I submitted (#1832) was actually to have it work this way.

[minimal-scouser]

i am working on this.

[stada526]

@minimal-scouser
I really appreciate it 🙏