Holochart

Changelog ​

All Holochart packages (@mk7s/holochart and every @mk7s/holochart-*) share one version number and are released together, so one list covers them all. Each entry names the packages it changed.

Under each version, changes are grouped by the size of the bump they ask for:

  • Minor changes add something (an attribute, a trace type, an export, an event, an option) or deprecate something. Before 1.0 a minor change may also break existing code; such an entry starts with "BREAKING:".
  • Patch changes are bug fixes, performance work, rendering fixes and documentation. They never contain a breaking API change. Rendered pixels may still differ (anti-aliasing, tick placement, text metrics).

The list is generated from the project's changesets: one note per change, written by the author of the change when it is merged.

No version has been published yet. The changes under "Unreleased" ship in the first release.

Unreleased ​

Merged, but not in a published version yet. The next release is a prerelease, published under the alpha npm dist-tag.

Minor changes ​

  • First public alpha of Holochart: declarative, Plotly-compatible charts drawn on the GPU with three.js. Figures are Plotly's { data, layout, config, frames }, with the same attribute names, defaults and events. All 14 packages share one version. This is an alpha on the alpha npm dist-tag: APIs may still change in any 0.x minor.

    Install ​

    • npm i @mk7s/holochart three gives the full bundle. TypeScript users also add @types/three. The individual packages (-core, -runtime, -traces-*, …) build smaller bundles with register(...).
    • three is a peer dependency, >=0.180.0 <0.187.0. The upper bound is the next three.js minor after the newest one tested in CI, and it is widened per release. @types/three is an optional peer with the same range for the packages whose types expose three's (@mk7s/holochart, -render, -runtime, -components, -traces-3d).
    • ESM-only. Every export has a default condition after import, so Node 22's require(esm) and tools that only know default can load the packages. The browsers supported have WebGL 2 and ES2022. Node ≥ 22 runs the renderer-free parts (@mk7s/holochart-core).
    • Locales are a separate install: @mk7s/holochart-locales.

    Chart types ​

    35 trace types, each with Plotly's attributes, defaults, hover and events:

    • Basic: scatter (markers, lines, splines, steps, text, error bars, areas with fill / stackgroup / groupnorm, bubbles), bar (grouped, stacked, relative, horizontal, base, periods), pie and donuts, table (virtualized rows, wrapped text, draggable column order), and a timeline() helper for Gantt charts.
    • Statistical (-traces-stats): histogram (Plotly's auto-binning, every histfunc / histnorm, cumulative), histogram2d, histogram2dcontour, box, violin, splom, parcoords (brushing, axis reordering) and parcats, plus a strip() helper.
    • Scientific (-traces-sci): heatmap (one GPU texture, zsmooth, annotated cells), contour (every contours.coloring, constraint contours, labels placed like Plotly's), image, and polar subplots with scatterpolar (radar charts) and barpolar (wind roses).
    • Financial (-traces-finance): ohlc and candlestick (range slider by default, %{change} in hover), waterfall, funnel, funnelarea and indicator (numbers, deltas, angular and bullet gauges).
    • Hierarchical and flow (-traces-hier): sunburst, treemap and icicle with Plotly's 750 ms drill-down transitions and path bar, and sankey (d3-sankey layout, draggable nodes, loops, and the link.flow particle extension).
    • 3D (-traces-3d): scene subplots (layout.scene, cameras, turntable / orbit / pan / zoom, touch, 3D hover with spikes, scene.annotations) with scatter3d (1M points in one draw call), surface, mesh3d (Delaunay, convex hull, alpha shapes), cone, streamtube, isosurface and volume (Plotly's stacked isosurfaces or GPU ray marching). Holochart extensions: bar3d, tube and ribbon lines, lit spheres, three.js materials and scene lights, chart.animateCamera and scene.autorotate.
    • 2.5D (full bundle): layout.view3d tilts cartesian subplots in perspective. depth, bevel and material extrude bars, funnels, waterfalls, heatmaps, filled areas, pies, treemaps and icicles, and hover, click and zoom stay exact on the tilted plane.

    Not yet supported Plotly traces: maps and geo (scattergeo, choropleth, scattermap, densitymap, …), carpet / scattercarpet / contourcarpet, scatterternary, and the quiver and streamline figure factories.

    Layout and components ​

    • Axes: linear, log, date and category / multicategory, with Plotly's tick generation and tickformat. Also rangebreaks, linked axes (matches), scaleanchor aspect locks, overlaying and shifted axes, spikelines, automargin, layout.grid and makeSubplots().
    • Legends: multiple legends (legend2, …), group titles, scrolling past maxheight, and click / double-click toggling as in Plotly.
    • Colorbars, annotations (with arrows, rich text, drag and clicktoshow), shapes (drawing and editing, addHline / addVrect helpers), layout images, updatemenus, sliders, the range slider and range selector, layout.selections, and the modebar with Plotly's buttons, custom buttons and the 3D group.
    • Rich text: Plotly's pseudo-HTML (<b>, <i>, <sup>, <span style>, links, …) in every text attribute. Text is drawn as SDF glyphs on the GPU.
    • Styling: marker.pattern fills, custom SVG-path marker symbols (symbols.register), emoji and image markers, styleRules (JSON conditions that style points by their data) and per-point style functions.

    Runtime API ​

    • Plotly's functional API: newPlot, react, restyle, relayout, update, addTraces, deleteTraces, moveTraces, extendTraces, prependTraces, purge, addFrames, deleteFrames, animate, toImage and downloadImage. There is also an object API (createChart(el, figure), getChart(el)) with chart.ready and update promises.
    • Events: Plotly's events (hover, click, selected, relayout, restyle, legendclick, sunburstclick, animatingframe, …), also under their plotly_* names. A listener that throws no longer stops the chart or the other listeners.
    • Interaction: hover modes (including unified hover), zoom, pan, box and lasso selection (on polar subplots too), scroll zoom, touch with pinch-zoom, and keyboard navigation between data points.
    • Animation: react with layout.transition and figure.frames with animate. Every Plotly easing is supported, points are matched by ids, and Plotly's Play / Pause buttons and frame sliders work.
    • Big data: streaming with extendTraces, min/max level of detail for lines of millions of points, and typed-array data.
    • Export: toImage / downloadImage to PNG, JPEG or WebP at any size and scale. chartToJSON / fromJSON round-trip figures.
    • Errors: without WebGL 2, newPlot rejects with WebGLUnavailableError and the container shows a note and the chart's text description. Errors extend HolochartError.

    Themes and the default look ​

    • New charts use the dark, dense holochart template, drawn with the bundled TeX Gyre Heros font. The font is loaded lazily and nothing is fetched from a CDN. Use layout.template: 'plotly-classic' (or setDefaultTemplate('plotly-classic')) for Plotly's own look.
    • 16 built-in themes: holochart, plotly-classic, high-contrast, high-contrast-dark, neon, and plotly.py's plotly, plotly_white, plotly_dark, ggplot2, seaborn, simple_white, presentation, xgridoff, ygridoff, gridon and none. holochart-dark is a deprecated alias of holochart.
    • Every plotly.py palette and colorscale, plus colors.register, colorways.register, fonts.register and defineTemplate.

    Express ​

    @mk7s/holochart-express builds figures from row objects, column objects, Apache Arrow tables or CSV, following Plotly Express (camelCase). The functions are scatter, line, area, bar, timeline, pie, histogram, box, violin, strip, ecdf, the density charts, imshow, scatterMatrix, the parallel charts, funnel, the polar charts, sunburst, treemap, icicle, scatter3d and line3d. They support facets, animationFrame, marginals, trendlines (OLS, LOWESS, rolling, expanding, EWM) and ff.distplot.

    Locales and accessibility ​

    • Locales: config.locale translates the UI and formats numbers and dates. @mk7s/holochart-locales ships plotly.js's 76 locales as ES modules and <script> files, and plotly.js locale modules register as they are. Arabic and Hebrew text is laid out right to left.
    • Accessibility: charts are role="figure" with a generated description, summaries of trends and extremes, and data tables (chart.describe(), config.a11y). There is keyboard access to points, legends, menus, sliders and the modebar. Also a high-contrast theme, the colorblind-safe Safe colorway, automatic patterns (a11y.patterns) and reduced-motion support.

    Script-tag builds ​

    • @mk7s/holochart/dist/holochart.iife.min.js defines window.Holochart, with three.js bundled. It is everything but 3D, and the bare jsDelivr / unpkg URL serves it. Types for the global are in @mk7s/holochart/global.
    • holochart-3d.iife.min.js is a 3D add-on, loaded after the main script of the same version. It adds 3D scenes, 3D traces and 2.5D, and reuses the main script's three.js.
    • Each locale is a script: @mk7s/holochart-locales/dist/scripts/holochart-locale-<code>.js.

    Known limitations ​

    • WebGL 2 only. There is no Canvas 2D or SVG fallback, and no SVG or PDF export (toImage gives raster images only).
    • Tested in Chromium. Visual and interaction tests run in headless Chromium. Firefox and Safari should work but aren't tested in CI.
    • Missing features: the Plotly traces listed under Chart types, non-Gregorian calendars, LaTeX, and keyboard navigation for most 3D traces.
    • Experimental APIs: the low-level render namespace and the trace and component contracts in @mk7s/holochart-runtime may change in any minor release.

    Packages: @mk7s/holochart, @mk7s/holochart-components, @mk7s/holochart-core, @mk7s/holochart-express, @mk7s/holochart-locales, @mk7s/holochart-render, @mk7s/holochart-runtime, @mk7s/holochart-themes, @mk7s/holochart-traces-3d, @mk7s/holochart-traces-basic, @mk7s/holochart-traces-finance, @mk7s/holochart-traces-hier, @mk7s/holochart-traces-sci, @mk7s/holochart-traces-stats.

  • Typed figures. @mk7s/holochart exports Figure, Data (every trace type, discriminated on type), Layout, Config and Frame, generated from the attribute schemas, and createChart, newPlot, react, addTraces, relayout, update and toImage check figures against them. Each trace package exports its trace types (ScatterTrace, …) and their union (TracesBasic, …); core's FigureInput<D, L> stays loose by default for partial bundles and plugins, and plugins add trace types to TraceTypes. restyle keeps untyped attribute paths. Published types now also compile under exactOptionalPropertyTypes.

    Packages: @mk7s/holochart, @mk7s/holochart-components, @mk7s/holochart-core, @mk7s/holochart-express, @mk7s/holochart-locales, @mk7s/holochart-render, @mk7s/holochart-runtime, @mk7s/holochart-themes, @mk7s/holochart-traces-3d, @mk7s/holochart-traces-basic, @mk7s/holochart-traces-finance, @mk7s/holochart-traces-hier, @mk7s/holochart-traces-sci, @mk7s/holochart-traces-stats.

  • A curated export surface. Nothing changes at runtime; this is about which names are API.

    BREAKING: @mk7s/holochart exports a list of names instead of everything its packages export. It keeps the chart API, typed figures, the trace and component modules, themes, errors, the documented helpers and the experimental plugin API. The plumbing the packages share with each other is gone from it (layoutBars, calcBar, supplyColorscaleDefaults, stashSplomAxis, RANGESELECTOR_Y_PAD, stripInternal, editDistance, warnOnce and about 600 more), and so is setBarExtruder. Those names stay exported from their @mk7s/holochart-* packages, tagged @internal: not API, no compatibility promise. The script-tag global window.Holochart has the same names as @mk7s/holochart.

    BREAKING: exports that were stable by default are now tagged. @internal: what only sibling packages import (in core, components and the trace packages). @experimental: what a plugin is written with, namely core's schema DSL (attr, the schema types and schema objects), color and date parsing and update planning, the trace packages' attribute schemas and calc types, the 3D scene API, and the Chart members emit, getCalcdata, previewRanges, commitRanges and refreshHover. The Chart constructor is @internal; use createChart.

    BREAKING: names that meant different things in different packages were renamed on the less public side.

    • core and runtime: Layout is now BaseLayout, Frame is FrameInput; core: LayoutTitle is BaseLayoutTitle. The plain names are the full bundle's types.
    • traces-basic, traces-finance, traces-hier, traces-sci: BarTrace, PieTrace, ScatterTrace, FunnelTrace, WaterfallTrace, IcicleTrace, TreemapTrace and HeatmapTrace are now BaseBarTrace, BasePieTrace and so on. The plain names are the full bundle's types, which add the 2.5D attributes.
    • traces-basic: TimelineOptions is TimelineFigureOptions; traces-stats: StripOptions is StripFigureOptions; express: AnimationOptions is AnimationFrameOptions.
    • Experimental names: core's TraceModule and ComponentModule are CoreTraceModule and CoreComponentModule, its RGBA and Primitive are RGBAColor and PrimitiveValue; the runtime's pointInPolygon is polygonContains; render's LineOptions is LinePrimitiveOptions.

    Types that leaked into the declarations under bundler-made names have real ones: core's AttrBuilders (the type of attr), the runtime's TraceIndices, and render's MeshLazy, LinesMarkers3DLazy, ExtrusionLazy and PatternCode namespaces (type-only).

    Migration: import the figure types of the full bundle from @mk7s/holochart as before (BarTrace, Layout, Frame are unchanged there). In a partial bundle, rename the types above. If you imported an @internal name, copy the code you need. See "Unreleased: a curated export list" in the migration guide.

    Packages: @mk7s/holochart, @mk7s/holochart-components, @mk7s/holochart-core, @mk7s/holochart-express, @mk7s/holochart-render, @mk7s/holochart-runtime, @mk7s/holochart-traces-3d, @mk7s/holochart-traces-basic, @mk7s/holochart-traces-finance, @mk7s/holochart-traces-hier, @mk7s/holochart-traces-sci, @mk7s/holochart-traces-stats.

  • Keyboard navigation reaches every chart family. With the plot area focused, the arrow keys now step through histogram bins, the statistics of each box and violin, heatmap, contour and histogram2d cells (a cell cursor: ← / → along the row, ↑ / ↓ along the column), funnelarea stages, sunburst, treemap and icicle nodes (← / → siblings, ↑ the parent, ↓ the first child; Enter drills and the cursor stays on its node), sankey nodes and links (↓ downstream, ↑ upstream), parcats categories, parcoords lines on each axis, polar points and bars, and scatter3d points. Every stop shows the hover label a pointer would get there and announces what it says, with its place in the chart ("row 2 of 3, column 1 of 4", "level 2, 1 of 5, children: 2").

    3D scenes take the view keys: Shift + arrows orbit the camera in 15° steps, + / - move it in and out and 0 resets it, each as one relayout of scene.camera.

    bar3d, cone, streamtube, isosurface, volume and mesh3d describe themselves to assistive technology (what is drawn, the box it spans, and a headline value), like scatter3d and surface.

    The code for all of this loads on first use, in one small chunk per trace package: the keyboard stops on a chart's first keyboard focus, the 3D descriptions right after a chart with a 3D trace is first described (it shows the generic line until then, and chart.describe() waits for it). The descriptions of scatter3d and surface moved into that chunk too. The script-tag build (holochart.iife.min.js) does not include the 2D families' stops yet; its 3D add-on includes the 3D chunk.

    Announcements read the lines of a hover label as a list, so a pie slice is now "Share: Alpha, 40, 40%, point 1 of 5." instead of "Share: Alpha 40 40%, point 1 of 5."

    For trace module authors: keyboardPoints may return stops that say where the arrows lead (KeyboardPoint.nav), show several labels (more) and bring their own announcement (say), or a list that builds its stops on demand (KeyboardStops); cartesian modules may have stops too. TraceModule.a11y loads a module's keyboardPoints, describe and keyboardView (view keys of a trace that is not on cartesian axes) from a chunk of its own. sceneA11y gives a trace built on the 3D scene its view keys, and HoverContext.height is the figure height for domain traces.

    Packages: @mk7s/holochart, @mk7s/holochart-runtime, @mk7s/holochart-traces-3d, @mk7s/holochart-traces-finance, @mk7s/holochart-traces-hier, @mk7s/holochart-traces-sci, @mk7s/holochart-traces-stats.

  • Maps. The new package @mk7s/holochart-traces-geo has the geo subplot (layout.geo, geo2, …) and the scattergeo and choropleth traces: Plotly's projections, scopes, fitbounds, graticule and base layers (land, ocean, coastlines, countries, lakes, rivers, subunits) at resolution 110 or 50; pan, zoom and rotate with Plotly's relayout keys; markers, great-circle lines, text and fill: 'toself' at lon / lat or at locations; and regions colored by value, from the basemap (locationmode 'ISO-3', 'USA-states', 'country names') or from your own geojson with featureidkey. Express gains hx.scatterGeo, hx.lineGeo and hx.choropleth.

    A 3D globe, which Plotly does not have: projection.type: 'globe3d' is the orthographic view drawn as a lit sphere, with the same rotation, scale, gestures and relayout keys. It turns by a matrix, so a rotation projects nothing at any resolution. On it scattergeo lines are arcs lifted above the surface (line.lift), and a choropleth's regions can rise as prisms by a second value (elevation, elevationscale), picked on the GPU so that nothing behind the globe or behind a prism is hit. These three attributes are Holochart's own and are ignored on a flat map. The globe's code is a lazy chunk, loaded when a figure has one.

    The full bundle does not include it, so an app without a map downloads no map code. Add it with one import; @mk7s/holochart depends on the package, so there is nothing more to install:

    ts
    import * as Holochart from '@mk7s/holochart';
import '@mk7s/holochart/geo';

    @mk7s/holochart/geo registers the package and re-exports it. A partial bundle registers it like any trace package: register(...tracesGeo). A scattergeo or choropleth trace, or layout.geo, on a chart without the package is ignored, and the warning now names the package and that import. The script-tag build has no maps yet.

    The basemap is Natural Earth 5.1.2 (public domain), built into the package as lazy chunks, two per resolution (about 40 kB gzipped for 1:110m, 285 kB for 1:50m), loaded when a map first needs them: a map makes no request outside the app's own bundle and works offline. Disputed boundaries are drawn by de facto control. The 15 projections of d3-geo are in the package's own code, and the country-name table of 'country names' is a lazy chunk of its own; Plotly's other projection types load d3-geo-projection in one lazy chunk the first time a figure names one.

    New config.topojsonURL (core), with Plotly's meaning: when set, basemap files are fetched from <url>/world_110m.json and so on instead of the bundled data. Unlike Plotly it defaults to empty, which fetches nothing. The holochart template has a geo block, so maps match the dark look (land a step above the background, lakes cut out of it).

    For subplot authors (runtime, experimental): SubplotViewportOptions.kind: '2d' gives a non-cartesian subplot a pixel-space viewport like a cartesian subplot's instead of a 3D camera; DomainLayoutContext.chart is the chart, for subplots that keep state from one layout pass to the next; and a component view with clickThrough lets a press it took for dragging become a click on the point under it. A hover label now goes away when a component drag starts, and no longer appears under a finger lifted after a touch pan.

    Render (experimental): MeshData.depthTest and depthWrite, for a mesh that lies on a surface already drawn; loadPicker() and loadFillTriangulation(), which give lazy code the pickers and the polygon triangulation without bringing them into an app's initial chunk.

    Packages: @mk7s/holochart, @mk7s/holochart-core, @mk7s/holochart-express, @mk7s/holochart-render, @mk7s/holochart-runtime, @mk7s/holochart-traces-geo.

  • More network graphs: two more trace types in @mk7s/holochart-traces-graph, interaction, accessibility and large graphs.

    • chord: a chord diagram, which Plotly does not have. Flows between nodes as ribbons inside a ring, from the node / link containers of graph and sankey or from a square matrix with labels. directed ribbons can end in an arrowhead (link.arrowlen), node.group adds an outer ring of groups, ribbons are colored by their source, their target or a gradient (link.colorsource), and a hover keeps the ribbons of one node. It is placed by domain.
    • graph3d: the graph model in a 3D scene: a force layout in three dimensions, 'layered' with one plane per rank, or 'preset' positions on the scene's axes. Nodes are lit spheres or sprites, links lines or tubes with cone arrowheads, parallel links fan out and a self-link is a ring. Nodes and links are picked on the GPU. Register it with tracesGraph3d, which brings the scene; tracesGraph alone bundles no 3D code. import '@mk7s/holochart/graph' registers both.
    • Interaction (graph): a hover highlights a node's neighbourhood (highlight.hops, direction, dim, color, nodes), and two selected nodes highlight a shortest path between them (highlight.path, pathweight, pathdirected; graphPath(trace) returns it). Nodes can be dragged under 'preset' and 'force' (node.draggable): the release restyles node.x / node.y, which pins a node of a force layout, and a double-click releases it; with force.simulate the layout reacts while a node is dragged. force.start continues a layout from given positions. Selection points list the links among the selected nodes, and %{neighbors} is a hover template variable.
    • Large graphs (graph): worker: 'auto' | true (or config.worker) runs the layout in the package's layout worker, dist/layout-worker.js, and draws the nodes while they settle; where a worker cannot start, the same code runs on the main thread in slices. lod leaves labels, arrowheads and node outlines out of a large graph until a zoom makes them readable, and fades links by how densely they cover the plot. link.bundle bundles links ('hierarchical' through the nodes' groups, 'force' for graphs without groups). Exported for apps that lay graphs out themselves: layoutInWorker, setGraphWorkerUrl, bundleLinks.
    • Accessibility: the description of a graph names its most-connected nodes, its connected components and its groups, and its data table is the list of links. Arrow keys move from a node along its links (siblings, parent and child in a tree; rank by rank in a layered graph), and Enter folds a tree node. Five new announcement sentences and Folded. are translated in the ten locales.

    For trace authors (experimental): TracePlotContext.recalc() asks for a second calc pass without a change of the figure (a layout that arrived); HoverPoint.selects names the points a click on this one selects; eventData gets the selection as a fourth argument; KeyboardPoint.click lets Enter reach the click handling of a cartesian trace that handles clicks itself; KeyboardStops.locate re-finds the cursor in stops built on demand. TraceAxisHints gains z, and a 3D scene whose traces all hide their axes hides its own and starts with a closer camera.

    Packages: @mk7s/holochart, @mk7s/holochart-core, @mk7s/holochart-locales, @mk7s/holochart-runtime, @mk7s/holochart-traces-3d, @mk7s/holochart-traces-graph.

  • A chart created in a hidden or unsized element (an inactive tab, a closed dialog) no longer stays at 700 × 450: without config.responsive it now takes the element's size once, the first time the element has one.

    New config.maxPixelRatio (default 2): the upper limit of the pixel ratio that pixelRatio: 'auto' takes from the display.

    Polar zoom-box drags work for charts in another window's document (an iframe or popup created by the page's script).

    An unknown trace type that is one of Holochart's own now says which package to register: "sankey is in @mk7s/holochart-traces-hier; import it from there and call register(sankey)". Core exports tracePackage, and the warn-once helpers warnOnce and deprecate. The new "Errors and warnings" reference page lists which calls reject and which warn.

    Packages: @mk7s/holochart-components, @mk7s/holochart-core, @mk7s/holochart-render, @mk7s/holochart-runtime, @mk7s/holochart-traces-sci.

  • Dashboards no longer run out of WebGL contexts. Browsers keep about 16 per page (8 on mobile) and blank the oldest canvas beyond that; a page of Holochart charts now uses at most 6 however many charts it has. The first 4 charts get a context of their own and later ones draw through one shared renderer, which renders each chart and copies the frame into that chart's canvas. toImage and downloadImage always draw through the shared renderer, so exporting no longer takes a context per call.

    New config.sharedRenderer: 'auto' (default), true to always share, false to always take a context. On a shared chart chart.three.renderer.domElement is not the chart's canvas: use chart.three.root.canvas. See the Dashboards guide and ADR-023.

    Packages: @mk7s/holochart-core, @mk7s/holochart-render, @mk7s/holochart-runtime, @mk7s/holochart-traces-3d, @mk7s/holochart-traces-hier.

  • Network graphs. The new package @mk7s/holochart-traces-graph has the graph trace, which Plotly does not have: nodes (node.label, x, y, size, color, symbol, group) and the links between them (link.source, target, value, color, width, dash, arrow), shaped like sankey's so the same data feeds both, or the ids / labels / parents of the hierarchical traces. Links can have arrowheads, which stop at the edge of their node, parallel links curve apart and a self-link is a loop. Nodes are markers, sized by node.size or by their number of links (node.sizeby), or boxes around their labels (node.shape: 'box'). Labels are culled where they collide: the most connected nodes keep theirs and the rest appear on zoom. Nodes are colored by group, with one legend item per group, or by value, with a colorbar. Hover works on nodes and links, and box and lasso selection on nodes.

    arrangement says where the nodes go. 'preset' takes node.x and node.y as data on the trace's axes, so a network can sit over a scatter, on date or log axes. Every other value computes the positions, with a deterministic layout that is also exported as a pure function over typed arrays, and each has an option container of its name:

    • 'force' (the default without positions; force): a force-directed layout, as springs and repulsion (force.algorithm: 'spring') or ForceAtlas2. Nodes with an x and a y are pinned; when every node has an x and none a y, the x axis stays a real axis and the layout only moves the nodes along y (a timeline). force.simulate: true shows the layout settling and ends on the same picture; it is skipped under prefers-reduced-motion and for graphs of more than 2,000 nodes or 10,000 links.
    • 'layered' (layered): a directed graph in layers (rankdir, ranksep, nodesep, ranker), with links routed as splines, polylines or right angles (routing). Labelled nodes are boxes and links have arrowheads by default; layered.clusters frames the nodes of each group under its name; the links of a cyclic graph that had to be turned around are drawn in the link.secondary style (dashed).
    • 'tree', 'radial', 'dendrogram' (tree): a tidy tree, the same tree on rings, and a tree with its leaves on one line and its nodes at the heights node.value gives, on a visible axis. They take ids / labels / parents or node / link; links that are not part of the tree are drawn in the link.secondary style. A click on a node that has children folds or unfolds its subtree: the chart restyles tree.collapsed and the tree moves to its new shape.
    • 'arc' (arc) and 'hive' (hive): an arc diagram and a hive plot.
    • 'circular' and 'grid', and 'custom', which runs a layout the app registered with registerGraphLayout(name, layout).

    New with them: node.value (a number per node: a dendrogram's heights, tree.sort, hive.position, %{value} in hover labels) and link.secondary (dash, opacity, color). Labels have room where the arrangement leaves some (node.textposition: 'auto'): along the radius of a radial tree, upright under an arc diagram or the leaves of a dendrogram. Box nodes of a computed arrangement shrink with the axes, text included, when the diagram is larger than the plot area.

    The trace is cartesian: it draws on its xaxis and yaxis, so zoom, pan, selection, uirevision, subplots and image export work as for a scatter. With a computed arrangement the axes are hidden, unless another trace shows them or the figure sets visible, and locked to one scale (a tidy tree and a dendrogram fill the plot area along each axis instead).

    The full bundle does not include it, so an app without a graph downloads no graph code. Add it with one import; @mk7s/holochart depends on the package, so there is nothing more to install:

    ts
    import * as Holochart from '@mk7s/holochart';
import '@mk7s/holochart/graph';

    @mk7s/holochart/graph registers the package and re-exports it. A partial bundle registers it like any trace package: register(...tracesGraph). A graph trace on a chart without the package is hidden, and the error names the package and that import. The script-tag build has no graphs yet.

    For trace authors (core, experimental): a trace module can give axisHints(trace), which returns a TraceAxisHints: hide (the axes, or with 'x' / 'y' that axis, default to visible: false unless another trace is on them), equal (the y axis defaults to scaleanchor on the trace's x axis), reverse ('x' or 'y': that axis defaults to autorange: 'reversed'), and x / y (the data the trace puts on its axes when that is not its x / y attribute, for axis type detection).

    Packages: @mk7s/holochart, @mk7s/holochart-core, @mk7s/holochart-traces-graph.

  • Accessibility strings in ten locales. de, es, fr, it, ja, ko, pt-BR, ru, tr and zh-CN now translate Holochart's own strings, which plotly.js's locales don't have: the generated chart summaries (until now de, es and fr only), every keyboard announcement ("Revenue: (Mar 1, 2024, 11), point 3 of 6.", "Zoomed in.", "View rotated.", the row, level and category sentences of grids, hierarchies and parcats), the name of the legend's keyboard toolbar and the plot area's keyboard hint. Regional locales that fall back to one of them (de-CH, es-AR, es-PE, fr-CH) get its strings; every other locale falls back to English, sentence by sentence (pt-PT, zh-TW and zh-HK fall back to pt-BR and zh-CN first when those are registered too, as they already did for Plotly's UI strings).

    The same ten locales also fill gaps among the UI strings a chart looks up: the titles of the modebar's drawing buttons ("Draw line", "Erase active shape", …), and in ko and pt-BR the hover labels of box, violin, OHLC and candlestick (open:, median:, …), which plotly.js has under keys without the colon, plus the default trace name in ko.

    These are machine translations that no native speaker has reviewed; the locales guide and the accessibility guide say so, and say what is still English: the rest of the hidden description (chart type sentence, axis and trace lines, table captions) and a few control names ("Chart toolbar", "Menu 1", "Slider 1", "Range selector"). To correct a sentence, register the locale with your own entry for its English key.

    A parcoords dimension without a label is now named through the locale dictionary in its keyboard stops ('Dimension {n}'), instead of always in English.

    The ten locale modules grow by 1 to 2.5 kB each (gzipped), to 3 to 4 kB; nothing is added to the core bundles. The locales guide now also states the limits of right-to-left text: legends, menus and axes are not mirrored, and measuring text without a browser has no bidi or shaping.

    Packages: @mk7s/holochart-locales, @mk7s/holochart-traces-stats.

  • BREAKING: chart.toJSON() is removed. Call chartToJSON(chart) instead; it returns the same figure and reads the chart's registry through the new chart.registry. The method made every bundle carry the serializer (about 2.3 kB), also in apps that never save a figure. JSON.stringify(chart) now throws a TypeError that names chartToJSON.

    Migration: replace chart.toJSON() with chartToJSON(chart), and JSON.stringify(chart) with JSON.stringify(chartToJSON(chart)).

    Packages: @mk7s/holochart, @mk7s/holochart-runtime.

  • Charts come back complete after the browser takes the WebGL context away and restores it (a GPU reset, a long time in a background tab). Buffers, textures, text and picking already did; a 3D scene's generated environment (lighting.environment: 'studio' | 'city') did not, which left metallic and physical materials black. It is now drawn again on webglcontextrestored.

    Texture sizes follow the device instead of an assumed 4096: chart.three.root.capabilities has the context's maxTextureSize and max3DTextureSize. Heatmaps pack their values into rows that fit, and a heatmap, image, surface or volume grid too large for the GPU logs a warning and is not drawn, instead of drawing black.

    Packages: @mk7s/holochart-render, @mk7s/holochart-traces-3d.

  • Express gains three network functions (experimental), which plotly.express does not have: hx.graph, hx.chord and hx.adjacencyMatrix. They read an edge table, one row per link with the ids of its two ends (source, target, weight), and an optional node table (nodes, matched by id) for labels, colors, sizes, symbols, positions and hover text. color groups the nodes, with one color and legend item per value, or maps a numeric column through a colorscale; size takes a column or 'degree'; directed draws arrowheads; arrangement picks the layout of a graph, with its options under the trace's own names (force, layered, tree, arc, hive). hx.chord also takes a square matrix. hx.adjacencyMatrix draws the network as a heatmap with rows and columns sorted by order ('input', 'degree', 'group', 'community' or a list of node indices), so that clusters show as blocks on the diagonal.

    The functions only build figures, so Express still depends on no trace package. Drawing a graph or a chord needs the graph package registered: import '@mk7s/holochart/graph'.

    @mk7s/holochart-traces-graph now exports its data helpers: the adapters fromEdgeList, fromAdjacencyMatrix, fromNodeLink (networkx, d3, graphology and Cytoscape JSON) and fromDot (a Graphviz subset), which return the node and link containers of a trace, and the measures degrees, connectedComponents, louvain, modularity and adjacencyMatrix. The Express functions take an adapter's result in place of the edge table, and a measure as a node column: hx.adjacencyMatrix(network, { color: louvain(network), order: 'community' }).

    Packages: @mk7s/holochart-express, @mk7s/holochart-traces-graph.

Patch changes ​

  • Stability tags. The plugin API is now marked @experimental in the published types, so editors show which exports may still change in a minor release: the render namespace (@mk7s/holochart-render, except the fonts and symbols registries), the trace and component contracts and the helpers for module authors in @mk7s/holochart-runtime and @mk7s/holochart-core, and the chart members typed by those (chart.three.root, .overlay, .viewports, .subplot(), chart.axes, chart.subplots, chart.interaction). Everything else a package exports is stable. Nothing changes at runtime. See the versioning section of the migration guide.

    Packages: @mk7s/holochart, @mk7s/holochart-core, @mk7s/holochart-render, @mk7s/holochart-runtime.

  • Large heatmaps draw sooner and lines cost less GPU time, with the same pixels.

    A 4096 × 4096 heatmap's first draw takes about half as long. Its values go to the GPU as one float per cell (R32F, 67 MB) instead of a value and a validity flag (RG32F, 134 MB), calc reads the rows once instead of twice, and the accessible description no longer scans all 16.7 million cells after every pipeline run. packHeatmapValues now returns one float per texel, with cells without a value stored as the largest float32.

    On a 1M-segment pan, a solid line costs 2.1 to 2.6 times three's Line2 instead of 3 to 4 times, and a dashed one 2.4 to 3 times instead of 8. A line with one color keeps it in a uniform instead of a per-vertex buffer (28 bytes per vertex instead of 44), a dashed line no longer recomputes and re-uploads its dash phase while panning, and each segment's quad ends where the pixels it draws end. New in @mk7s/holochart-render: quadReach, QUAD_FRINGE and QUAD_SLACK (the CPU mirror of the quad's extent).

    Packages: @mk7s/holochart-render, @mk7s/holochart-traces-sci.

  • 3D scenes no longer leave two GPU buffers behind each time their axes are rebuilt at a different size. On the shared renderer those buffers outlived the chart.

    Packages: @mk7s/holochart-traces-3d.

  • Charts created at the same time no longer show text with letters missing. The text engine keeps one glyph atlas for the page and reports a label as typeset as soon as its glyphs are registered; when another chart had asked for the same new glyphs a moment earlier, that was before they were in the texture, and the chart kept the gaps until something else redrew it ("Hourly precipitation (in)" read "ourl pre ipitation in"). Text primitives now watch the atlas together: when typesetting or preloadTextFont adds glyphs, every chart with text draws one more frame.

    Packages: @mk7s/holochart-render.

  • Docs: a chemistry and physics basics demo page that walks through the periodic table, what things are made of, atoms and molecules, motion, waves, fields and the planets with more than 50 charts across 33 trace types, from heatmap, sunburst, parcats and bar3d to isosurface, volume, cone, streamtube, image and an animated pendulum.

    Packages: @mk7s/holochart.

  • Docs: a Dallas weather demo page that charts 87 years of daily readings from Dallas Love Field (NOAA): every daily high and low on one zoomable date axis, the year in days against its records, calendar and month-by-year heatmaps, rain through the year, a wind rose, a 3D temperature landscape, a climate spiral and an animated seasonal curve.

    Packages: @mk7s/holochart.

  • Docs: a TQQQ and SOXL demo page that charts 16 years of the two 3× ETFs, their holdings and how daily leverage behaves, with candlestick, OHLC, indicator, heatmap, 3D bar, surface, contour, sankey, sunburst, treemap, icicle, parcoords, parcats, splom, violin and more.

    Packages: @mk7s/holochart.

  • Hover: %{text} in a hovertemplate, and the text line of hoverinfo, now read text when hovertext is empty, its default, as in Plotly (hovertext || text). Before, %{text} came out empty for most trace types (scatter, bar, bar3d, …), and a template of only %{text} showed no label.

    Packages: @mk7s/holochart-runtime.

Released under the MIT License.

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