v0.5.0 — contributed plot types

Released 2026-09-24.

The contributed-plot-types release: another package can add a mode to the plot-type selector at runtime. The first one is dianne-js's Digital Pathology - DIANNE (freehand DIANNE labelling over the image view). Backwards compatible: no public type changes shape, and a host that provides no contributions sees no change.

Added

• Contributed plot types (PLOT_TYPE_CONTRIBUTIONS). A multi-provider token with no factory: nothing registers at import time, and a contribution is a plain object, so the contributing package needs neither decorators nor the Angular compiler.
  • Base type: a contributed mode rides on a built-in baseType (in this version only PlotType.IMAGE, the OpenSeadragon view). It is plotted exactly as that type would be, with its toolbar, region tools and wheel handling.
  • Activation: once the viewport is ready, activate(ctx) receives the public IVisualizer, a PlotModeViewport and the image stream.
  • Deactivation: the session is deactivated exactly once, when the user leaves the mode, the image changes or the base view re-renders, or the visualizer is destroyed.
  • Gates: descriptors take the requiresGrayscale / requiresStack / requiresSpatialData / requiresSpatial3d gates, on top of their base type's own.
  • Side panel (optional): either an Angular component, which injects PLOT_MODE_CONTEXT / PLOT_MODE_SESSION, or a framework-agnostic mount(host, ctx, session) function. It sits in the right-hand panel area.
  • Isolation: nothing a contribution throws or rejects escapes. Failing to start (activate, mount, a panel component throwing as it is first rendered) falls back to the base type with a warning toast. So does failing to clean up (throw or async rejection) while the same mode is being re-activated. An explicit re-selection in the dropdown retries it.
• A viewport to draw over, on the OpenSeadragon backend.
  • dataToClient (image px to client px) alongside clientToData.
  • A per-redraw frame$, coalesced to one emission per animation frame and idle while nothing listens, and settled$ (the existing getViewportChange$). Each starts with the current visible rect, so an overlay draws without waiting for a pan.
  • IVisualizer gains an optional getPlotModeViewport().
• VisualizerComponent fields: plotTypeMenu (the selector's full list: built-ins, then contributed modes) and selectedPlotTypeId (the selector's id, a built-in type or a contributed one).
• New exports: PLOT_TYPE_CONTRIBUTIONS, PLOT_MODE_CONTEXT, PLOT_MODE_SESSION, PlotTypeContribution, ContributedPlotTypeDescriptor, PlotModeContext, PlotModeViewport, PlotModeSession, PlotModePanel, PlotModeRect, PlotTypeOption, PlotTypeId and isBuiltinPlotType.

Changed

• Unchanged public types: VisualizerComponent.plotTypeOptions remains PlotTypeDescriptor[] (the built-in types on offer) and selectedPlotType remains PlotType. The latter is the built-in type on screen: the selection itself, or a contributed mode's baseType while one is active. The selector now binds to plotTypeMenu / selectedPlotTypeId.
• Internal: the unexported toolbar's plot-type input and output now carry PlotTypeId, and it takes a basePlotType input. Every rendering and tool decision still takes a PlotType: a contributed id is resolved to its base type first.

Fixed

These three are in the example app and tile server, which are not part of the npm package.

• Tile-server container: runs on Node 22. lib/zarr3.mjs needs zstdDecompressSync from node:zlib, which does not exist before Node 22.15, so the node:20-slim image died on import. engines.node now says >=22.15.0.
• Pages smoke test: no longer fails the deploy against a tile server that predates the spatial routes. The app already handles that server by offering no spatial entries. A 4xx on that server's spatial/ paths is tolerated and named in the build log; every other 4xx still fails the test.
• Demo dataset label: the synthetic demo dataset's gallery label now says the expression is fabricated ("SYNTHETIC · fabricated expression · Visium geometry (demo)"), so it is not taken for measurements next to the real datasets.

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npm: @jax-data-science/sci-image-visualizer@0.5.0
Full diff: v0.4.0...v0.5.0