Charts Backlog

Features and chart types planned for future releases.

Feature API sketch Description
Annotations

Options for marking up the chart area with reference context. The base annotations API (vertical and horizontal point/range markers) ships in v0.9.5 — see Annotations. Items below are follow-ups.

Annotations on Bar (time-series mode) annotations on RareCharts.Bar Wire the same annotations API into Bar when its data has a date field. Useful for marking events on daily volume or transaction-count bars.
Callouts and image overlays callouts: [{ x, y, text, image, dx, dy }] Text callouts and image overlays anchored to data coordinates or pixel positions inside the chart area. Distinct from annotations: callouts are free-form content at arbitrary (x, y) rather than axis-aligned markers.
Band series

The band (confidence-ribbon) series ships on RareCharts.Line in v0.9.6 — see Bands. Items below extend it.

Bands on Time Series and Dual Axes type: 'band' on RareCharts.TimeSeries / RareCharts.DualAxes Wire the same { date, lower, upper } band series into the other date-based chart classes. Useful for confidence ranges on a zoomable price feed or alongside a bar/line dual-axis layout. Currently band rendering lives only in Line.
New chart types
Candlestick RareCharts.Candlestick OHLCV candlestick chart for price and financial data visualization.
Hierarchies RareCharts.Hierarchies Spatial hierarchy views — treemap, pack, sunburst, cluster — over the tree contract that shipped in v0.9.8_2 (see Hierarchical Bar for the linear outline and the node shape; Donut drills the same tree).
Scatter RareCharts.Scatter Two-metric point chart: [{ x, y, label?, size?, color? }] with optional size/color encoding, quadrant reference lines, and point labels. The workhorse of comparison analytics — risk vs. return, valuation vs. growth, any "rank N items on two axes" figure. Targeted for v0.9.8_3.
Heatmap RareCharts.Heatmap Matrix of [{ row, column, value }] cells colored by a diverging or sequential scale, with row/column labels and a cell tooltip. Covers sector-by-period performance grids and correlation matrices. Targeted for v0.9.8_3.
Waterfall RareCharts.Waterfall Sequential deltas from a start value to an end value with connector lines and subtotal steps — the earnings-bridge / P&L-decomposition staple of financial reporting. Targeted for v0.9.8_3.
Composition & stacking

Stacked bars ship on Bar in v0.9.8_2 — see Stacked Bar. Multi-series Line areas still overlap rather than accumulate; items below extend composition.

Stacked area stacked: true on RareCharts.Line area series Accumulate multi-series areas instead of overlapping them, including a 'percent' mode normalizing each slice to 100%. Targeted for v0.9.8_3.
Stacked bars on date slots [{ name, values: [{ date, value }] }] on RareCharts.Bar Extend the v0.9.8_2 categorical stack to the time-series bar mode: segments stacked per date slot, with the shared timeframe controls.
All chart types in MultiChart type: 'Donut' | 'Gauge' | 'DualAxes' | ... in charts descriptors Extend the MultiChart composition grid beyond Line and Bar to every chart class, and warn on an unknown type instead of silently falling back to Line. Unblocks mixed dashboard blocks — a KPI gauge next to a trend line under one shared header. Targeted for v0.9.8_4.
Scales & transforms
Logarithmic Y scale yScale: 'log' on Line / TimeSeries / DualAxes Log-scale toggle for long-horizon price and index series, where a linear scale visually overstates recent moves. Requires positive-domain guards and log-aware tick generation. Targeted for v0.9.8_4.
Series rebase / normalization normalize: 'rebase' | 'percent' on RareCharts.Line Re-express every series relative to its value at the start of the visible window — rebase to 100 or cumulative percent change — so multi-asset comparisons share one axis. Recomputes on zoom/timeframe change, which is why it belongs in the chart rather than in data prep. Targeted for v0.9.8_4.
Bar series
Bar value labels barLabels: true Renders formatted value labels above positive bars and below negative bars. Uses yTickFormat for formatting. Available on Bar and DualAxes.
Bar width control barWidth: number Absolute bar width in px as an alternative to the proportional barWidthRatio. Supports per-series override.
Per-bar color override data: [{ label, value, color }] Allow an individual bar to specify its own fill color without redefining the full chart palette. Useful for highlighting a selected category, outlier, or benchmark item.
Diverging bar chart RareCharts.DivergingBar Bar chart centered on a shared baseline for before/after, left/right, positive/negative, or category comparison layouts. Targeted for v0.9.8_3.
Map
Map overlays and labels layers: [{ type, data, ... }] Add overlay layers to maps for extra information such as points, routes, bubbles, labels, markers, or other contextual geographic annotations.
Clickable map regions onRegionClick: ({ feature, item, event }) => void or item.href Allow clicking a region to trigger navigation or custom actions. Intended for drill-down flows, region detail pages, dashboards, and linked geographic navigation.
Graph
Directed and multiple graph relations optional edge direction, identity and labels Support directed relations and multiple simultaneous relations between the same pair of nodes. Allow optional edge labels and values such as ownership percentages, while keeping the minimum link payload at { source, target }. Direction, relation IDs, percentages and other domain fields must enrich the result when present, not become required input.
Graph details panel node and relation details surface Add a proper HTML details surface for a selected node or relation. It should show whatever metadata is available — relation type, share, dates, source, confidence and the full filterable connection list — without requiring any of those fields. The hover tooltip remains a compact summary and links to the details surface when more information exists.
Graph ownership layout view: 'ownership' Add an optional deterministic hierarchy for ownership and control chains: owners above, controlled entities below, direction made explicit, and percentages or relation labels shown when supplied. It is a specialized presentation over the general graph contract, not a required ownership-specific schema.
Graph cluster-view strategies configurable aggregation and layout Revisit cluster after relation filtering, richer edges and details are available. Explore pluggable strategies for community structure, industry roles, value chains, geography and ownership groups, with the current Louvain overview retained as a general default. Domain-specific grouping must be opt-in and may be supplied by the data source instead of inferred client-side.
Graph chrome styling zoom controls, capacity note, navigation Align the +/−/⟲ zoom buttons, actionable +N more disclosure, breadcrumbs and details controls with Rare Styles: proper icons, spacing, positioning, focus and hover states, responsive behavior, and dark-theme support.
Interactivity
Legend series isolation legendInteractive: true Clicking a legend item isolates that series. All others are dimmed. Clicking the active item or double-clicking restores all series. Targeted for v0.9.8_4.
Tooltip header style theme.tooltip.header Dedicated theme token for the tooltip header row (date label). Allows independent control of header background and text color, separate from tooltip.bg and tooltip.text.
Arbitrary in-chart labels labels: [{ x, y, text, dx, dy, color }] or per-series labelFormat Render custom text labels directly inside the chart area for lines, bars, and highlighted values. Intended for editorial annotations, direct labeling, and reducing reliance on legends or tooltips.
Branding
Branding API RareCharts.setBrand(config) Global brand configuration applied to all chart instances: logo image (rendered as a watermark), accent color, and font family. Eliminates per-chart theme repetition in multi-chart dashboards.