feat(next): native Generic Viewport migration (useNextViewports)

[sedghi]

Linked integration test: builds this OHIF branch against the cornerstone3D PR branch cornerstoneohifnextapi (cornerstonejs/cornerstone3D#2766) and runs the Playwright suite. Add/keep the ohif-integration label. The CS3D Branch Merge Guard intentionally fails while CS3D_REF points to a branch; switch to a published version once the CS3D PR merges.

Summary

Work-in-progress migration to render OHIF viewports on cornerstone3D's native Generic ("next") viewport API, gated behind the useNextViewports opt-in flag. Legacy rendering is unchanged when the flag is off.

This is a draft for ongoing review; it contains WIP commits and depends on parallel cornerstone3D work (branch cornerstoneohifnextapi).

Highlights so far

• Render native Generic (next) stack, volume/MPR, and 3D viewports behind useNextViewports.
• Presentation bridge (getViewportProperties/setViewportProperties) so VOI/colormap/invert work across legacy and next backends.
• TMTV fusion parity: colorbar shows the correct (PT) colormap and value range, linear opacity slider (100% = full PT), and a lower native default fusion opacity (0.4).
• Dual-backend segmentation handling.

Recent next-viewport parity fixes

• Window-level overlay (W:/L:) now refreshes when the display set changes in a next viewport.
• Data overlay (e.g. PET on CT) comes in at the legacy-equivalent initial opacity (~40%) instead of ~80–90% on the native (flat-blend) path.
• Changing orientation on a CT+PET fusion preserves the fusion (CT background + PET colormap/opacity) instead of collapsing to PET-only.
• Hydrating a DICOM SEG preserves the base image window/level (no brightness shift) instead of restoring a stale computed VOI.
• Stack→MPR keeps the slice scrollbar in sync with the rendered slice, and the acquisition (axial) MPR view centers the volume like legacy instead of pinning to the first slice.

Synced with latest master.

Status

Draft — not ready to merge. Open for incremental review feedback.

Summary by CodeRabbit

• New Features

  • Added support for the newer native viewport experience, including updated segmentation, rendering, and overlay handling.
  • Improved viewport controls so orientation, colorbars, window/level, opacity, and threshold tools work more consistently across viewport types.

• Bug Fixes

  • Fixed segmentation display for overlapping and multi-layer SEG data.
  • Improved slice navigation, progress bars, and orientation markers for better behavior during viewport changes.
  • Prevented missing or incorrect overlay/image references during viewport load and measurement navigation.

Greptile Summary

This draft PR introduces the useNextViewports opt-in path for rendering OHIF viewports on cornerstone3D's native Generic ("next") viewport API, adding a clean backend-split architecture (Legacy/Next pairs for both viewport service and segmentation service) behind a single flag seam with an automated allowlist guard.

• Backend split: LegacyViewportBackend/NextViewportBackend and LegacyViewportOperations/nextViewportOperations extract per-lane mount dispatch, position/LUT presentation, and viewport operations into typed, testable classes — the legacy off-path is byte-identical to the original code.
• Native mount paths: native stack, volume/MPR, and 3D viewports are mounted via setDisplaySets + setDisplaySetPresentation + setViewState; the DataIdRegistry ref-counts global provider registrations across shared MPR panes.
• Presentation bridge: getViewportPresentation.ts bridges legacy getProperties/setCamera to native getDisplaySetPresentation/setViewState so colorbar, W-L toolbar, and the opacity slider work across both backends.

Confidence Score: 4/5

Not ready to merge — fusion viewport appearance (PT colormap/VOI) is silently dropped on every navigation cycle in the native path, and the download capture misses overlay bindings for fusion viewports.

The native fusion LUT save/restore only captures the source (CT) binding: _getLutPresentation calls getViewportProperties without a dataId on PLANAR_NEXT, reading only the source binding. For a PT/CT fusion, the PT overlay colormap, VOI range, and threshold are never saved and never restored on nav-away-and-back. The download capture has the same gap. Both are isolated to the native fusion path and the overall backend architecture is sound.

extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts (_getLutPresentation native branch) and extensions/cornerstone/src/utils/CornerstoneViewportDownloadForm.tsx (native fusion capture path)

Important Files Changed

Filename	Overview
extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts	Large refactor: backend split for mount dispatch, LUT/position presentation, and dataId lifecycle. Native fusion LUT save/restore only captures the source (CT) binding — PT appearance is dropped on every nav-away-and-back cycle.
extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts	New native viewport backend: owns position/LUT presentation for PLANAR_NEXT viewports and ref-counted dataId lifecycle. The setLutPresentation only reads/writes the source binding for fusion viewports.
extensions/cornerstone/src/services/ViewportService/backends/NextViewportOperations.ts	Native operations lane: scaleBy calls vp.getZoom()/setZoom() without optional-chain guards; would throw on non-PLANAR native types if those receive a scale command.
extensions/cornerstone/src/services/ViewportService/backends/dataIdRegistry.ts	Ref-counted lifecycle for the global GenericViewport metadata provider. Correct across shared MPR dataIds; byViewport list grows unboundedly on repeated remounts without release.
extensions/cornerstone/src/services/ViewportService/backends/viewportOperations.ts	Thin per-viewport dispatcher routing to legacy or native operations lane. Clean design, no issues.
extensions/cornerstone/src/services/SegmentationService/backends/NextSegmentationBackend.ts	Never promotes PLANAR_NEXT to ORTHOGRAPHIC; builds multi-layer overlapping SEG labelmaps correctly.
extensions/cornerstone/src/utils/CornerstoneViewportDownloadForm.tsx	Native capture only transfers source-binding presentation; fusion overlay appearance is not captured.
extensions/cornerstone/src/utils/getViewportPresentation.ts	Clean bridge: correctly dispatches to getDisplaySetPresentation/setViewState (native) or getProperties/setCamera (legacy) for all four helpers.
extensions/cornerstone/src/hooks/useViewportRendering.tsx	Adds native-aware opacity gamma and per-binding property reads. resolveOpacityScalar fix for array-valued opacity is correct.
.scripts/check-next-viewports-flag-reads.mjs	CI guard for the flag-read allowlist. Logic is sound.

Comments Outside Diff (1)

1. extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts, line 450-460 (link)

   LUT presentation only captures the source binding for native fusion viewports

   For a native PT/CT fusion viewport, isVolumeViewportType(csViewport) is false (PLANAR_NEXT is not ORTHOGRAPHIC), so the code takes the non-Map branch and calls getViewportProperties(csViewport) without a dataId. That reads vp.getDisplaySetPresentation(vp.getSourceDataId()) — the CT (source) binding only. The PT overlay colormap, VOI range, and threshold are never saved. When setLutPresentation later calls nativeViewport.setDisplaySetPresentation(presentationProps) (also without a dataId) it again targets the source binding, so the PT appearance is silently dropped on every navigation-away-and-back cycle.

   Prompt To Fix With AI

   This is a comment left during a code review.
   Path: extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts
   Line: 450-460
   
   Comment:
   **LUT presentation only captures the source binding for native fusion viewports**
   
   For a native PT/CT fusion viewport, `isVolumeViewportType(csViewport)` is `false` (PLANAR_NEXT is not ORTHOGRAPHIC), so the code takes the non-Map branch and calls `getViewportProperties(csViewport)` without a `dataId`. That reads `vp.getDisplaySetPresentation(vp.getSourceDataId())` — the CT (source) binding only. The PT overlay colormap, VOI range, and threshold are never saved. When `setLutPresentation` later calls `nativeViewport.setDisplaySetPresentation(presentationProps)` (also without a `dataId`) it again targets the source binding, so the PT appearance is silently dropped on every navigation-away-and-back cycle.
   
   How can I resolve this? If you propose a fix, please make it concise.

_{Reviews (4): Last reviewed commit: "fix(next): address review findings (guar..." | Re-trigger Greptile}

[sedghi]

@coderabbitai review

[coderabbitai]

@sedghi I'll review the changes now.

✅ Action performed

Review finished.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[coderabbitai]

Actionable comments posted: 6

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (3)

extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts (1)

604-610: 🎯 Functional Correctness | 🟠 Major | ⚡ Quick win

Restore Map-backed LUT presentations for fusion bindings.

mountVolumes replays lutPresentation, but this branch drops Map properties entirely. Native fusion presentations are per display-set/dataId, so overlay PT VOI/colormap/threshold state will not restore on remount/navigation.

Proposed fix

-    const nativeViewport = viewport as unknown as {
-      setDisplaySetPresentation: (props: Record<string, unknown>) => void;
-    };
-    const presentationProps: Record<string, unknown> = {};
-    if (properties.voiRange) {
-      presentationProps.voiRange = properties.voiRange;
-    }
-    if (properties.invert !== undefined) {
-      presentationProps.invert = properties.invert;
-    }
-    if (properties.colormap) {
-      presentationProps.colormap = properties.colormap;
-    }
-    if (Object.keys(presentationProps).length > 0) {
-      nativeViewport.setDisplaySetPresentation(presentationProps);
-    }
+    const nativeViewport = viewport as unknown as {
+      setDisplaySetPresentation: (
+        dataIdOrProps: string | Record<string, unknown>,
+        props?: Record<string, unknown>
+      ) => void;
+    };
+    const toNativePresentationProps = (entry: Record<string, unknown>) => {
+      const presentationProps: Record<string, unknown> = {};
+      for (const key of ['voiRange', 'invert', 'colormap', 'opacity', 'threshold']) {
+        if (entry[key] !== undefined) {
+          presentationProps[key] = entry[key];
+        }
+      }
+      return presentationProps;
+    };
+
+    if (properties instanceof Map) {
+      properties.forEach((entry, dataId) => {
+        const presentationProps = toNativePresentationProps(entry);
+        if (Object.keys(presentationProps).length > 0) {
+          nativeViewport.setDisplaySetPresentation(dataId, presentationProps);
+        }
+      });
+      return;
+    }
+
+    const presentationProps = toNativePresentationProps(properties);
+    if (Object.keys(presentationProps).length > 0) {
+      nativeViewport.setDisplaySetPresentation(presentationProps);
+    }

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In
`@extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts`
around lines 604 - 610, The LUT replay in mountVolumes is currently skipping
Map-backed presentations, which prevents fusion-specific per-display-set state
from being restored. Update the handling around lutPresentation.properties so
NextViewportBackend can replay Map entries for native fusion bindings instead of
returning early, while still preserving the existing non-Map
getDisplaySetPresentation path. Use the mountVolumes logic and the
setDisplaySetPresentation flow in NextViewportBackend as the place to reapply
each dataId/display-set presentation, including VOI/colormap/threshold state.

extensions/cornerstone/src/commandsModule.ts (1)

1288-1317: 🩺 Stability & Availability | 🟠 Major | ⚡ Quick win

Guard missing viewport before setting colormap.

getCornerstoneViewport(viewportId) can return null; this path then calls ops.setColormap(viewport, ...) and may render a missing viewport. Add the same early return used by the other operation-delegated commands.

Proposed fix

       const viewport = cornerstoneViewportService.getCornerstoneViewport(viewportId);
+      if (!viewport) {
+        return;
+      }
 
       let hpOpacity;

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@extensions/cornerstone/src/commandsModule.ts` around lines 1288 - 1317, The
colormap command path in commandsModule.ts does not guard against
getCornerstoneViewport(viewportId) returning null before calling
ops.setColormap. Add the same early return/null-check pattern used by the other
operation-delegated commands in this module so the command exits when the
viewport is missing. Use the getCornerstoneViewport and ops.setColormap flow
here to locate the fix and keep the orthographic/displaySetInstanceUID logic
unchanged.

extensions/cornerstone/src/hooks/useViewportRendering.tsx (1)

289-311: 🗄️ Data Integrity & Integration | 🟡 Minor | ⚡ Quick win

Don't substitute the display-set UID for an unresolved dataId. getPresentation() and getDefaultVOIRange() already fall back to the active binding when called with no id; passing activeDisplaySetInstanceUID here bypasses that path and can return the wrong or empty VOI/presentation for unresolved legacy volume bindings. Pass dataId through unchanged instead.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@extensions/cornerstone/src/hooks/useViewportRendering.tsx` around lines 289 -
311, The VOI lookup in useViewportRendering is incorrectly substituting
activeDisplaySetInstanceUID when dataId is unresolved, which can bypass the
adapter’s intended fallback behavior. Update the getPresentation and
getDefaultVOIRange calls to pass dataId through unchanged so the viewport
adapter can resolve the active binding correctly for both native and legacy
viewports. Keep the existing voiRange handling in useViewportRendering and the
adapter methods getPresentation/getDefaultVOIRange as the reference points for
the fix.

🧹 Nitpick comments (1)

extensions/cornerstone/src/services/ViewportService/Viewport.ts (1)

230-239: 📐 Maintainability & Code Quality | 🔵 Trivial | ⚡ Quick win

Reuse the new getViewportDataShapeType helper instead of re-deriving inline.

This ternary (dataShapeType ?? viewportType) is identical to getViewportDataShapeType just added in extensions/cornerstone/src/utils/viewportDataShape.ts. Consolidating avoids the two copies drifting if the discriminator logic ever changes.

♻️ Suggested consolidation

+import { getViewportDataShapeType } from '../../utils/viewportDataShape';
+
 public hasDisplaySet(displaySetInstanceUID: string): boolean {
   let viewportData = this.getViewportData();
-  const dataShapeType = viewportData.dataShapeType ?? viewportData.viewportType;
+  const dataShapeType = getViewportDataShapeType(viewportData);

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@extensions/cornerstone/src/services/ViewportService/Viewport.ts` around lines
230 - 239, The viewport data shape discriminator is duplicated here in the
ViewportService logic, so replace the inline `viewportData.dataShapeType ??
viewportData.viewportType` fallback with the shared `getViewportDataShapeType`
helper from `getViewportDataShapeType` in
`extensions/cornerstone/src/utils/viewportDataShape.ts`. Update the code path
around `Viewport` handling to use that helper wherever `dataShapeType` is
needed, keeping the existing `Enums.ViewportType.ORTHOGRAPHIC` and
`Enums.ViewportType.VOLUME_3D` checks unchanged.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In
`@extensions/cornerstone/src/services/ViewportService/adapter/LegacyViewportAdapter.ts`:
- Around line 213-239: `LegacyViewportAdapter.copyDisplayedContentTo` only
copies the first volume and global properties, which causes fusion overlays and
per-volume display state to be dropped in captures/downloads. Update this method
to copy every bound volume from the source viewport onto the target, preserving
the full multi-volume stack used by `CornerstoneViewportDownloadForm.tsx`, and
then apply each volume’s specific properties through the target’s per-volume
`setProperties` path instead of a single shared call. Keep the existing view
presentation and view reference փոխանց, but make sure the target viewport is
fully reconstructed with all source volumes and their individual
VOI/colormap/opacity settings.

In
`@extensions/cornerstone/src/services/ViewportService/adapter/NextViewportAdapter.ts`:
- Around line 186-195: The volume lookup in getVoxelManagerForDisplaySet
currently uses an unanchored includes() match on cache.getVolumes(), which can
select the wrong cached volume when another volumeId contains the same
displaySetInstanceUID substring. Update the matching logic in
NextViewportAdapter so it uses an anchored comparison such as
endsWith(displaySetInstanceUID) or an exact volumeId check against the
`${volumeLoaderSchema}:${displaySetInstanceUID}` format, then keep returning the
matched volume’s voxelManager as before.

In
`@extensions/cornerstone/src/services/ViewportService/backends/LegacyViewportBackend.ts`:
- Around line 137-142: The WSI registration added in mountOther via
csUtils.genericViewportDisplaySetMetadataProvider is never released, leaving
stale global state across viewport reuse. Track the displaySetId registration
when adding the GenericViewport metadata entry, then implement the viewport
disable/destroy lifecycle hooks in LegacyViewportBackend to remove that entry
from csUtils.genericViewportDisplaySetMetadataProvider for the same
displaySetId.
- Around line 156-157: The remount camera snapshot in
LegacyViewportBackend.remount is taken too early, before the viewport family
check, so unsupported families can throw instead of returning undefined. Move
the getCamera() access on vp to after the stack/volume guards in remount, and
only snapshot the camera for IStackViewport and IVolumeViewport paths while
preserving the documented no-op behavior for ECG/video/WSI families.

In
`@extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts`:
- Around line 450-452: The persistence logic in CornerstoneViewportService
currently stores a single presentation object for Generic fusion viewports via
getViewportAdapter(csViewport).getPresentation(), which drops overlay-specific
LUT/PT VOI state. Update the code around isVolumeViewportType(csViewport) and
getViewportAdapter(csViewport) so native fusion persists presentation data per
bound display-set/binding, matching the legacy volume path that saves separate
entries. Make sure the saved state includes all bound display-set presentations,
not just one cleanProperties(getPresentation()) result.
- Around line 1391-1398: The remount flow in CornerstoneViewportService should
not assume this.backend.remount always returns a promise. In the remount
handling block, guard the result from remount(...) before calling .then(), since
it may be undefined for viewport families without a remount path. Either return
early when no promise is returned or normalize the value in displaySetPromise
handling so the existing .then() chain only runs when a real promise exists.

---

Outside diff comments:
In `@extensions/cornerstone/src/commandsModule.ts`:
- Around line 1288-1317: The colormap command path in commandsModule.ts does not
guard against getCornerstoneViewport(viewportId) returning null before calling
ops.setColormap. Add the same early return/null-check pattern used by the other
operation-delegated commands in this module so the command exits when the
viewport is missing. Use the getCornerstoneViewport and ops.setColormap flow
here to locate the fix and keep the orthographic/displaySetInstanceUID logic
unchanged.

In `@extensions/cornerstone/src/hooks/useViewportRendering.tsx`:
- Around line 289-311: The VOI lookup in useViewportRendering is incorrectly
substituting activeDisplaySetInstanceUID when dataId is unresolved, which can
bypass the adapter’s intended fallback behavior. Update the getPresentation and
getDefaultVOIRange calls to pass dataId through unchanged so the viewport
adapter can resolve the active binding correctly for both native and legacy
viewports. Keep the existing voiRange handling in useViewportRendering and the
adapter methods getPresentation/getDefaultVOIRange as the reference points for
the fix.

In
`@extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts`:
- Around line 604-610: The LUT replay in mountVolumes is currently skipping
Map-backed presentations, which prevents fusion-specific per-display-set state
from being restored. Update the handling around lutPresentation.properties so
NextViewportBackend can replay Map entries for native fusion bindings instead of
returning early, while still preserving the existing non-Map
getDisplaySetPresentation path. Use the mountVolumes logic and the
setDisplaySetPresentation flow in NextViewportBackend as the place to reapply
each dataId/display-set presentation, including VOI/colormap/threshold state.

---

Nitpick comments:
In `@extensions/cornerstone/src/services/ViewportService/Viewport.ts`:
- Around line 230-239: The viewport data shape discriminator is duplicated here
in the ViewportService logic, so replace the inline `viewportData.dataShapeType
?? viewportData.viewportType` fallback with the shared
`getViewportDataShapeType` helper from `getViewportDataShapeType` in
`extensions/cornerstone/src/utils/viewportDataShape.ts`. Update the code path
around `Viewport` handling to use that helper wherever `dataShapeType` is
needed, keeping the existing `Enums.ViewportType.ORTHOGRAPHIC` and
`Enums.ViewportType.VOLUME_3D` checks unchanged.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 8ad9ad55-ce7a-4804-bc2d-4052670b7c75

📥 Commits

Reviewing files that changed from the base of the PR and between 880b346 and 812e823.

📒 Files selected for processing (50)

• extensions/cornerstone-dicom-seg/src/commandsModule.ts
• extensions/cornerstone/src/Viewport/Overlays/CustomizableViewportOverlay.tsx
• extensions/cornerstone/src/Viewport/Overlays/ViewportImageScrollbar.tsx
• extensions/cornerstone/src/Viewport/Overlays/ViewportOrientationMarkers.tsx
• extensions/cornerstone/src/Viewport/Overlays/ViewportSliceProgressScrollbar/helpers.ts
• extensions/cornerstone/src/Viewport/Overlays/ViewportSliceProgressScrollbar/hooks.ts
• extensions/cornerstone/src/commandsModule.ts
• extensions/cornerstone/src/components/ViewportOrientationMenu/ViewportOrientationMenu.tsx
• extensions/cornerstone/src/components/ViewportWindowLevel/utils.ts
• extensions/cornerstone/src/getToolbarModule.tsx
• extensions/cornerstone/src/hooks/useViewportRendering.tsx
• extensions/cornerstone/src/index.tsx
• extensions/cornerstone/src/init.tsx
• extensions/cornerstone/src/services/ColorbarService/ColorbarService.ts
• extensions/cornerstone/src/services/CornerstoneCacheService/CornerstoneCacheService.ts
• extensions/cornerstone/src/services/SegmentationService/SegmentationService.ts
• extensions/cornerstone/src/services/SegmentationService/backends/ISegmentationBackend.ts
• extensions/cornerstone/src/services/SegmentationService/backends/NextSegmentationBackend.ts
• extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts
• extensions/cornerstone/src/services/ViewportService/Viewport.ts
• extensions/cornerstone/src/services/ViewportService/adapter/IViewportAdapter.contract.test.ts
• extensions/cornerstone/src/services/ViewportService/adapter/IViewportAdapter.ts
• extensions/cornerstone/src/services/ViewportService/adapter/LegacyViewportAdapter.ts
• extensions/cornerstone/src/services/ViewportService/adapter/NextViewportAdapter.ts
• extensions/cornerstone/src/services/ViewportService/adapter/getViewportAdapter.ts
• extensions/cornerstone/src/services/ViewportService/adapter/index.ts
• extensions/cornerstone/src/services/ViewportService/backends/IViewportBackend.ts
• extensions/cornerstone/src/services/ViewportService/backends/IViewportOperations.ts
• extensions/cornerstone/src/services/ViewportService/backends/IViewportServiceInternals.ts
• extensions/cornerstone/src/services/ViewportService/backends/LegacyViewportBackend.ts
• extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts
• extensions/cornerstone/src/services/ViewportService/backends/NextViewportOperations.ts
• extensions/cornerstone/src/services/ViewportService/backends/README.md
• extensions/cornerstone/src/services/ViewportService/backends/dataIdRegistry.ts
• extensions/cornerstone/src/services/ViewportService/backends/viewportOperations.ts
• extensions/cornerstone/src/utils/CornerstoneViewportDownloadForm.tsx
• extensions/cornerstone/src/utils/getCornerstoneViewportType.test.ts
• extensions/cornerstone/src/utils/getCornerstoneViewportType.ts
• extensions/cornerstone/src/utils/getDataIdForViewport.ts
• extensions/cornerstone/src/utils/getLegacyViewportType.ts
• extensions/cornerstone/src/utils/nextViewportPolicies.ts
• extensions/cornerstone/src/utils/nextViewports.ts
• extensions/cornerstone/src/utils/viewportDataShape.ts
• extensions/default/src/utils/layerConfigurationUtils.ts
• extensions/tmtv/src/getHangingProtocolModule.ts
• extensions/tmtv/src/utils/hpViewports.ts
• platform/app/src/utils/preserveQueryParameters.ts
• platform/ui-next/src/components/SegmentationTable/SegmentationTableConfig.tsx
• scripts/check-next-viewport-boundaries.sh
• tests/Scoord3dProbe.spec.ts

💤 Files with no reviewable changes (4)

• tests/Scoord3dProbe.spec.ts
• scripts/check-next-viewport-boundaries.sh
• platform/ui-next/src/components/SegmentationTable/SegmentationTableConfig.tsx
• extensions/cornerstone/src/utils/getDataIdForViewport.ts

✅ Files skipped from review due to trivial changes (2)

• extensions/cornerstone/src/services/ViewportService/backends/README.md
• extensions/tmtv/src/utils/hpViewports.ts

🚧 Files skipped from review as they are similar to previous changes (15)

• extensions/tmtv/src/getHangingProtocolModule.ts
• extensions/cornerstone/src/services/ViewportService/backends/IViewportServiceInternals.ts
• extensions/cornerstone/src/Viewport/Overlays/ViewportOrientationMarkers.tsx
• extensions/cornerstone/src/Viewport/Overlays/ViewportImageScrollbar.tsx
• extensions/cornerstone/src/init.tsx
• extensions/cornerstone/src/Viewport/Overlays/CustomizableViewportOverlay.tsx
• extensions/cornerstone/src/services/ViewportService/backends/IViewportOperations.ts
• extensions/cornerstone/src/services/SegmentationService/backends/ISegmentationBackend.ts
• extensions/cornerstone/src/services/SegmentationService/backends/NextSegmentationBackend.ts
• extensions/cornerstone/src/services/ViewportService/backends/dataIdRegistry.ts
• extensions/cornerstone/src/services/CornerstoneCacheService/CornerstoneCacheService.ts
• extensions/cornerstone/src/utils/getCornerstoneViewportType.test.ts
• extensions/cornerstone/src/utils/getCornerstoneViewportType.ts
• extensions/cornerstone-dicom-seg/src/commandsModule.ts
• extensions/cornerstone/src/services/SegmentationService/SegmentationService.ts

[coderabbitai]

🎯 Functional Correctness | 🟠 Major | ⚡ Quick win

Fusion overlay lost in captured/downloaded image for multi-volume viewports.

copyDisplayedContentTo only mounts volumeIds[0] on the target and applies a single, non-per-volume getProperties() call. For a legacy PT/CT fusion (multi-volume) viewport, this drops the overlay volume entirely from the target, and even if it were mounted, its per-volume colormap/VOI/opacity/threshold wouldn't be copied (since setProperties is called without a volumeId). The download/capture form (CornerstoneViewportDownloadForm.tsx) depends on this method to reproduce the source's full displayed state, so fusion captures will silently lose the overlay.

This is consistent with the PR's own review note that native fusion LUT presentation capture around the download path is incomplete — the legacy lane has the analogous gap.

🐛 Proposed fix to copy all bound volumes and their per-volume properties

     if (isStackViewportType(targetViewport)) {
       const imageId = this.viewport.getCurrentImageId?.();
       await targetViewport.setStack?.([imageId]);
+      targetViewport.setProperties?.(properties);
     } else if (isVolumeViewportType(targetViewport)) {
       const volumeIds = this.getVolumeIds();
-      await targetViewport.setVolumes?.([{ volumeId: volumeIds[0] }]);
+      await targetViewport.setVolumes?.(volumeIds.map(volumeId => ({ volumeId })));
+      volumeIds.forEach(volumeId => {
+        const volumeProperties = this.viewport.getProperties?.(volumeId);
+        if (volumeProperties) {
+          targetViewport.setProperties?.(volumeProperties, volumeId);
+        }
+      });
     }

     if (viewPresentation && targetViewport.setViewPresentation) {
       targetViewport.setViewPresentation(viewPresentation);
     }

-    targetViewport.setProperties?.(properties);
-
     if (viewRef && targetViewport.setViewReference) {
       targetViewport.setViewReference(viewRef);
     }

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	async copyDisplayedContentTo(target: CoreTypes.IViewport): Promise<void> {
	const targetViewport = target as unknown as LegacyViewport;
	const viewRef = this.viewport.getViewReference?.();
	// - properties: VOI, colormap, interpolation, etc.
	// - viewPresentation: flip/rotate/zoom presentation state (preserves flip/rotate)
	const properties = this.viewport.getProperties?.();
	const viewPresentation = this.viewport.getViewPresentation?.();
	if (isStackViewportType(targetViewport)) {
	const imageId = this.viewport.getCurrentImageId?.();
	await targetViewport.setStack?.([imageId]);
	} else if (isVolumeViewportType(targetViewport)) {
	const volumeIds = this.getVolumeIds();
	await targetViewport.setVolumes?.([{ volumeId: volumeIds[0] }]);
	}
	if (viewPresentation && targetViewport.setViewPresentation) {
	targetViewport.setViewPresentation(viewPresentation);
	}
	targetViewport.setProperties?.(properties);
	if (viewRef && targetViewport.setViewReference) {
	targetViewport.setViewReference(viewRef);
	}
	}
	async copyDisplayedContentTo(target: CoreTypes.IViewport): Promise<void> {
	const targetViewport = target as unknown as LegacyViewport;
	const viewRef = this.viewport.getViewReference?.();
	// - properties: VOI, colormap, interpolation, etc.
	// - viewPresentation: flip/rotate/zoom presentation state (preserves flip/rotate)
	const properties = this.viewport.getProperties?.();
	const viewPresentation = this.viewport.getViewPresentation?.();
	if (isStackViewportType(targetViewport)) {
	const imageId = this.viewport.getCurrentImageId?.();
	await targetViewport.setStack?.([imageId]);
	targetViewport.setProperties?.(properties);
	} else if (isVolumeViewportType(targetViewport)) {
	const volumeIds = this.getVolumeIds();
	await targetViewport.setVolumes?.(volumeIds.map(volumeId => ({ volumeId })));
	volumeIds.forEach(volumeId => {
	const volumeProperties = this.viewport.getProperties?.(volumeId);
	if (volumeProperties) {
	targetViewport.setProperties?.(volumeProperties, volumeId);
	}
	});
	}
	if (viewPresentation && targetViewport.setViewPresentation) {
	targetViewport.setViewPresentation(viewPresentation);
	}
	if (viewRef && targetViewport.setViewReference) {
	targetViewport.setViewReference(viewRef);
	}
	}

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In
`@extensions/cornerstone/src/services/ViewportService/adapter/LegacyViewportAdapter.ts`
around lines 213 - 239, `LegacyViewportAdapter.copyDisplayedContentTo` only
copies the first volume and global properties, which causes fusion overlays and
per-volume display state to be dropped in captures/downloads. Update this method
to copy every bound volume from the source viewport onto the target, preserving
the full multi-volume stack used by `CornerstoneViewportDownloadForm.tsx`, and
then apply each volume’s specific properties through the target’s per-volume
`setProperties` path instead of a single shared call. Keep the existing view
presentation and view reference փոխանց, but make sure the target viewport is
fully reconstructed with all source volumes and their individual
VOI/colormap/opacity settings.

[coderabbitai]

🎯 Functional Correctness | 🟡 Minor | ⚡ Quick win

🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
# Find where native volumeIds are constructed to confirm the naming convention is collision-safe.
rg -n "volumeId" extensions/cornerstone/src/services/ViewportService/backends -A3 -B3

Repository: OHIF/Viewers

Length of output: 18470

---

🏁 Script executed:

#!/bin/bash
set -euo pipefail

# Inspect the native backend where volumeIds are passed through or generated.
ast-grep outline extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts --view expanded

echo "---- references to volumeId / displaySetInstanceUID in backend ----"
rg -n "volumeId|displaySetInstanceUID|getVolumes\(|includes\(displaySetInstanceUID\)" \
  extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts \
  extensions/cornerstone/src/services/ViewportService/backends -A3 -B3

echo "---- file that uses the lookup in question ----"
sed -n '180,205p' extensions/cornerstone/src/services/ViewportService/adapter/NextViewportAdapter.ts

echo "---- data-id registration semantics ----"
sed -n '1,120p' extensions/cornerstone/src/services/ViewportService/backends/dataIdRegistry.ts

Repository: OHIF/Viewers

Length of output: 50368

---

🏁 Script executed:

#!/bin/bash
set -euo pipefail

# Find where volumeIds are created or normalized, and whether they embed the displaySetInstanceUID
# with a delimiter/prefix that makes substring matching unambiguous.
rg -n "volumeId\s*[:=]|create.*volumeId|make.*volumeId|volumeId.*displaySetInstanceUID|displaySetInstanceUID.*volumeId|::overlay|cached volumeId|already-cached volumeId" \
  extensions/cornerstone/src/services -A3 -B3

echo "---- dataIdRegistry (focused) ----"
sed -n '35,90p' extensions/cornerstone/src/services/ViewportService/backends/dataIdRegistry.ts

echo "---- NextViewportBackend volume-mount area (focused) ----"
sed -n '413,490p' extensions/cornerstone/src/services/ViewportService/backends/NextViewportBackend.ts

Repository: OHIF/Viewers

Length of output: 29745

---

Use an anchored volumeId match here. volumeId is built as ${volumeLoaderSchema}:${displaySetInstanceUID}, so includes() can still return the wrong cached volume when another id contains the same UID substring. endsWith(displaySetInstanceUID) or an exact id compare would be safer.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In
`@extensions/cornerstone/src/services/ViewportService/adapter/NextViewportAdapter.ts`
around lines 186 - 195, The volume lookup in getVoxelManagerForDisplaySet
currently uses an unanchored includes() match on cache.getVolumes(), which can
select the wrong cached volume when another volumeId contains the same
displaySetInstanceUID substring. Update the matching logic in
NextViewportAdapter so it uses an anchored comparison such as
endsWith(displaySetInstanceUID) or an exact volumeId check against the
`${volumeLoaderSchema}:${displaySetInstanceUID}` format, then keep returning the
matched volume’s voxelManager as before.

[coderabbitai]

🩺 Stability & Availability | 🟠 Major | ⚡ Quick win

Release legacy WSI provider registrations.

mountOther adds a WSI entry to the global GenericViewport metadata provider, but the lifecycle hooks remain no-ops. Track these registrations and remove them on viewport disable/destroy to avoid stale provider state across viewport reuse.

Also applies to: 244-254

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In
`@extensions/cornerstone/src/services/ViewportService/backends/LegacyViewportBackend.ts`
around lines 137 - 142, The WSI registration added in mountOther via
csUtils.genericViewportDisplaySetMetadataProvider is never released, leaving
stale global state across viewport reuse. Track the displaySetId registration
when adding the GenericViewport metadata entry, then implement the viewport
disable/destroy lifecycle hooks in LegacyViewportBackend to remove that entry
from csUtils.genericViewportDisplaySetMetadataProvider for the same
displaySetId.

[coderabbitai]

🗄️ Data Integrity & Integration | 🟠 Major | 🏗️ Heavy lift

Persist native fusion LUT state per binding, not as one presentation object.

For Generic volume/fusion viewports, isVolumeViewportType(csViewport) can be false, so this path stores only getViewportAdapter(csViewport).getPresentation(). That loses overlay-specific PT VOI/colormap/threshold across navigation; capture all bound display-set presentations for native fusion the same way legacy volumes persist per-volume entries.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In
`@extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts`
around lines 450 - 452, The persistence logic in CornerstoneViewportService
currently stores a single presentation object for Generic fusion viewports via
getViewportAdapter(csViewport).getPresentation(), which drops overlay-specific
LUT/PT VOI state. Update the code around isVolumeViewportType(csViewport) and
getViewportAdapter(csViewport) so native fusion persists presentation data per
bound display-set/binding, matching the legacy volume path that saves separate
entries. Make sure the saved state includes all bound display-set presentations,
not just one cleanProperties(getPresentation()) result.