fix for changing opacity based on segment index

[minimal-scouser]

Context

Fixes #1832

While rendering, segment styles such as opacity, fill etc do not consider active segment based on its index.

Changes & Results

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

Screen.Recording.2025-02-18.at.10.34.13.PM.mov

Testing

Checklist

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  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.

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[stada526]

Thank you for addressing the issue I raised!

[sedghi]

I think I messed up by merging this. I thought the opacity was at the segmentation level, but it seems to be segment-specific. Could you please create a pull request to revert this change? My reasoning is that there's only one layer of opacity change at the API level, which is between Segmentations, not within them. If someone needs a different opacity for any active segment, they can use the perSegment configuration.

This PR also cannot get merged, #1836 as it is adding another layer of opacity configuration at api level. There is already API for perSegment configuration

@minimal-scouser @stada526

[minimal-scouser]

doing it. but i don't think perSegment styles are taking effect.

and that is because the perSegment API is available for labelMaps not for contour segments.

contour segments use getSVGStyleForSegment for getting styles

@sedghi

[minimal-scouser]

per segment styles are not respected

the original intent itself is not aligned to support perSegment styles

cornerstone3D/packages/tools/src/stateManagement/segmentation/SegmentationStyle.ts

Lines 21 to 22 in 06ebd68

	// per segmentation we follow the same active and inactive style properties
	// since the target (segmentation) is important not the activeness etc

look at updatedStyles - it is basically the styles set at segmentation level

cornerstone3D/packages/tools/src/stateManagement/segmentation/SegmentationStyle.ts

Lines 98 to 117 in 06ebd68

	const currentStyles = this.getStyle(specifier);
	let updatedStyles: RepresentationStyle;
	if (!viewportId && !segmentationId) {
	// Global style setting
	updatedStyles = {
	...currentStyles,
	...styles,
	};
	} else {
	// Per segmentation or per viewport style setting
	updatedStyles = this.copyActiveToInactiveIfNotProvided(
	{
	...currentStyles,
	...styles,
	},
	type
	);
	}

and here we are assigning the high level styles to segment level style

cornerstone3D/packages/tools/src/stateManagement/segmentation/SegmentationStyle.ts

Lines 146 to 155 in 06ebd68

	if (segmentIndex !== undefined) {
	// Style for a specific segment
	if (!repConfig.perSegment) {
	repConfig.perSegment = {};
	}
	repConfig.perSegment[segmentIndex] = updatedStyles;
	} else {
	// Style for all segments of the segmentation
	repConfig.allSegments = updatedStyles;
	}

[sedghi]

I think they are working at least in OHIF, since this is the effect we have in OHIF, if you look at SegmentationService in OHIF you will see it

https://viewer-dev.ohif.org/viewer?StudyInstanceUIDs=1.3.6.1.4.1.32722.99.99.62087908186665265759322018723889952421

CleanShot.2025-02-21.at.12.46.30.mp4

see how per segment we apply different thickness

[minimal-scouser]

true. it works for visibility. even in the original example.

but it does not consider fillAlphaInactive, fillOutlineInactive - especially at segment level.

try this,

go to https://viewer-dev.ohif.org/segmentation?StudyInstanceUIDs=2.16.840.1.114362.1.11972228.22789312658.616067305.306.2

create two segments (under same segmentation)

run

cornerstoneTools.segmentation.config.style.getStyle({segmentationId: "Segmentation 1", type: "Contour"})

and this is what you will get

{
    "renderOutline": true,
    "outlineWidthAutoGenerated": 3,
    "outlineWidth": 1,
    "outlineWidthInactive": 1,
    "outlineOpacity": 1,
    "outlineOpacityInactive": 0.85,
    "outlineDashAutoGenerated": "5,3",
    "activeSegmentOutlineWidthDelta": 0,
    "renderFill": false,
    "fillAlpha": 0.5, <---------
    "fillAlphaInactive": 0.3, <----------
    "fillAlphaAutoGenerated": 0.3
}

notice how fillAlpha and fillAlphaInactive have different values yet on the viewport, there is no difference.

but ofcourse, you see a change in the opacity, the moment you create a new segmentation.