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

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  semantic-release format and guidelines.

Code

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  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

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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