NEWS

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vellumwidget 0.3.0.9000

vellumwidget 0.3.0

• Adopted vellum's renamed vl_* graphics primitives (grid collision fix).

• Shiny input read-back. A widget rendered with vellumwidgetOutput() now reports the user's interactions to the server as reactive inputs keyed by the output id: input$<id>_selected (selected keys, state), input$<id>_click (list(key=), event), input$<id>_hover (hovered key or NULL, state), and input$<id>_brush (list(keys=, x0=, y0=, x1=, y1=), event). Values are element data keys, so they map straight back to your data. Emitted only in a live Shiny session — a static render is unchanged and produces no input traffic. See the new Using vellumwidget in Shiny article. (Driving the widget from the server — a vellumwidget_proxy() — is a planned follow-up.)

• Accessibility (a11y = TRUE, on by default). The interactive widget is now keyboard- and screen-reader-navigable, not a mute image:

  • the SVG is announced as an interactive chart (role="graphics-document" + aria-roledescription), labelled from the scene's title/description (which vellumplot sets automatically) or an explicit as_widget(alt =);
  • every mark is a focusable graphics-symbol with a roving tabindex — arrow keys move between marks, Enter/Space toggles selection, Escape exits;
  • a polite aria-live region announces the focused / selected mark;
  • a visually-hidden data table lists every mark for assistive tech. All gated on a11y; a11y = FALSE restores the previous output exactly. See the vellumplot Accessibility article.

vellumwidget 0.2.0

Interaction-depth release (ROADMAP §4).

• Rich tooltips. Tooltip text now renders as safe HTML: an author-built tooltip = (e.g. via glue()) may use <b>/<i>/<br> for bold/italic/ line breaks. Data values are escaped and only inert, attribute-free tags are honoured — no scripts, handlers, or attributes (no XSS). New as_widget(tooltip_style =) themes the tooltip box (background/color/fontsize/ max_width).
• Touch + keyboard. The widget is driven by pointer events, so pan/brush/ hover work with mouse, touch, and pen from one path; a two-finger pinch zooms. With the widget focused, arrow keys pan, +/- zoom, and 0 resets.
• Configurable export. as_widget(export_filename =, export_scale =) set the download filename base and a hi-res PNG multiplier; exports capture the current (zoomed/panned) view. A "copy PNG to clipboard" toolbar button appears where the Clipboard API is available.
• Large-N performance. Hover/selection highlighting uses a per-render key→node cache instead of a querySelectorAll per key, and the nearest-mark hover scan is throttled to one per animation frame.
• New "Interactive widgets: a tour" article.

Deferred: a spatial index for hit-testing (the DOM cost was the real bottleneck, now cached; bbox scans are cheap and datashade collapses huge clouds to a raster); coordinated zoom across linked widgets and URL deep-linking; PDF export.

vellumwidget 0.1.0

First release. vellumwidget turns a vellum scene or a vellumplot plot into a self-contained, client-side interactive HTML widget via a single terminal as_widget() pipe — no Shiny, no server round-trip. Everything below ships in this first release.

Features

• as_widget() compiles a vellumplot plot or a raw vellum scene and bundles its SVG + scene_model() element table into an htmlwidget.
• Hover — tooltip (from the declared tooltip, falling back to the key) and highlight with inverse-dim; a hovered element's hover_group highlights the whole group. Hover snaps to the nearest mark when the cursor isn't directly over one.
• Click — select (single / multiple modes); every element sharing a key toggles together.
• Brush — drag a rectangle to select every element it covers.
• Pan / zoom — mouse wheel and pan-mode drag reframe the SVG viewBox, plus zoom-to-selection and reset.
• Toolbar (on hover) — brush/pan mode toggle, zoom-to-selection, reset zoom, download SVG, download PNG, fullscreen.
• Everything is opt-outable via as_widget() arguments (tooltip/hover/select/brush/zoom/toolbar/nearest).
• Legend interaction. For a discrete color/shape scale on an interactive plot, each legend swatch drives its whole data series: hovering a swatch highlights the series (the swatch stays lit), clicking it selects the series (and links across views / crosstalk). Automatic — no extra arguments.
• Linked views. as_widget(group=) links vellumwidget widgets client-side (no dependency): selecting/brushing in one highlights the same data keys in the others, projecting by hover_group (select one, select the series). as_widget(crosstalk = SharedData) bridges to the crosstalk ecosystem (plotly / leaflet / DT and filter_* inputs) via a SelectionHandle + FilterHandle; a crosstalk filter hides the non-matching marks (display-tier cross-filter). crosstalk is a Suggests, loaded only when used.
• Customisable interaction styling, at two composing levels:
  • Widget theme — as_widget(hover_color=, selected_color=, dim_opacity=) sets the look for the whole plot (any R or CSS colour).
  • Per-element grammar — vellumplot marks' hover_color/selected_color (constant or column-mapped) style each element individually and override the theme. Both use CSS variables with a defaults ← theme ← per-element cascade.

The JS runtime is TypeScript in srcts/, bundled by esbuild into the committed inst/htmlwidgets/vellumwidget.js (so the R package installs with no Node).