# Synchronized charts with zoom, pan and presets

Two years of daily prices and volumes as two charts that move as one: hover either for a shared crosshair, Ctrl + wheel or pinch to zoom around the pointer, Shift + drag or the hand button to pan, 1W / 1M / 3M / 6M / YTD / 1Y / All presets, and a grid that shows exactly the rows in the window. Right-click for a context menu with export, zoom and series items plus your own. Below: bars that grow in and slide on every data change with multi-selection, and a sunburst that drills down on click with a breadcrumb back up.

Uses `@svgrid/grid` (MIT). Category: Charts. Live demo: https://svgrid.com/demos/436-chart-sync-zoom/

Install: `npm i @svgrid/grid` (Svelte 5).

## About this example

Two years of daily prices and volumes as two Svelte 5 charts that move as one. A shared syncGroup gives them one crosshair and one zoom window; Ctrl + wheel or a pinch zooms around the pointer, Shift + drag or the hand button pans, and 1W, 1M, 3M, 6M, YTD, 1Y and All presets jump. The zoom window is a bindable prop, so the grid under the charts shows exactly the rows in it. Right-click opens a context menu with export, zoom and series items plus your own. Below, bars that grow in and slide on every data change with multi-selection, and a sunburst that drills down on click with a breadcrumb back up. Free, in @svgrid/grid.

Two years of daily prices and volumes, drawn as two charts that behave as one:

- `syncGroup="ticker"` on both. Hover either and both show the crosshair; zoom either and both follow. Nothing else is wired between them.
- `zoomable={{ wheel: 'modifier', pinch: true, pan: true }}`: Ctrl + wheel zooms around the pointer, a pinch does the same on touch, Shift + drag (or the hand button) pans a zoomed chart, a plain drag still rubber-bands.
- `rangePresets` puts 1W / 1M / 3M / 6M / YTD / 1Y / All in the toolbar.
- `bind:zoom` hands the window back as category indices, and the grid under the charts shows exactly the rows in it.
- `contextMenu` adds a right-click menu with the built-in export / zoom / series items plus one of ours, built from the clicked day.
- `animate={{ enter: 'wipe' }}` reveals the price line left to right.
- `tooltipPosition="top-right"` on the volume chart parks its tooltip in the corner so it never covers the bar being read, and `tooltipSticky` pins it on a click (Escape or a click outside lets go).

Below: a bar chart whose data reshuffles with a `grow` enter and a tween on every update, with multi-selection; and a sunburst that drills down on click with a breadcrumb back up.

Free, in @svgrid/grid.

## Imports, features and API used

- Imports: `@svgrid/grid`
- Table features registered: `rowSortingFeature`
- Columns: `date` (Date), `close` (Close), `change` (Change), `volume` (Volume)

## Frequently asked questions

### How do two charts share a crosshair?

Give both the same syncGroup name. Categories are matched by label first, then by date when both parse, so a daily and a weekly chart still meet at the right week. There is nothing else to wire.

### Why does a plain wheel scroll the page?

zoomable.wheel is set to modifier, so the chart only takes the wheel with Ctrl or Cmd held. Set it to true and the chart takes every wheel event over the plot.

### Is the zoom window a pixel range?

No, it is a pair of category indices into the full spec, i0 and i1, or null for everything. That is why the grid can slice its rows from it and why the window survives a resize.

## Related documentation

- [Financial charts](https://svgrid.com/docs/help/charts/financial.md)
- [Interaction: tooltips, zoom, sync, selection](https://svgrid.com/docs/help/charts/interaction.md)
- [Integrated charts](https://svgrid.com/docs/help/charts.md)
- [`<sv-chart>` reference](https://svgrid.com/docs/help/web-components/sv-chart.md)

## Related articles

- [Sparkline Cells in a Svelte Data Grid](https://svgrid.com/blog/sparkline-cells/) - Show inline trend sparklines inside grid cells using SvGrid's built-in sparkline column property - no charting library needed, just a field that holds a number array.

## Source code (436-chart-sync-zoom.svelte)

```svelte
<!-- Documented in: docs/help/charts/interaction.md -->
<script lang="ts">
  /**
   * 436. Synchronized charts with zoom, pan and presets
   * ----------------------------------------------------
   * Two years of daily prices and volumes, drawn as two charts that behave as
   * one:
   *
   * - `syncGroup="ticker"` on both. Hover either and both show the crosshair;
   *   zoom either and both follow. Nothing else is wired between them.
   * - `zoomable={{ wheel: 'modifier', pinch: true, pan: true }}`: Ctrl + wheel
   *   zooms around the pointer, a pinch does the same on touch, Shift + drag
   *   (or the hand button) pans a zoomed chart, a plain drag still rubber-bands.
   * - `rangePresets` puts 1W / 1M / 3M / 6M / YTD / 1Y / All in the toolbar.
   * - `bind:zoom` hands the window back as category indices, and the grid
   *   under the charts shows exactly the rows in it.
   * - `contextMenu` adds a right-click menu with the built-in export / zoom /
   *   series items plus one of ours, built from the clicked day.
   * - `animate={{ enter: 'wipe' }}` reveals the price line left to right.
   * - `tooltipPosition="top-right"` on the volume chart parks its tooltip in
   *   the corner so it never covers the bar being read, and `tooltipSticky`
   *   pins it on a click (Escape or a click outside lets go).
   *
   * Below: a bar chart whose data reshuffles with a `grow` enter and a tween
   * on every update, with multi-selection; and a sunburst that drills down on
   * click with a breadcrumb back up.
   *
   * Free, in @svgrid/grid.
   */
  import {
    SvChart, SvGrid, tableFeatures, rowSortingFeature,
    type ChartPointRef, type ChartSpec, type ChartZoomWindow, type GridColumns,
  } from '@svgrid/grid'

  const features = tableFeatures({ rowSortingFeature })

  // ---- Two years of daily data, seeded so every load draws the same chart.
  type Day = { date: string; close: number; volume: number; change: number }
  const days: Day[] = (() => {
    let seed = 11
    const rnd = () => ((seed = (seed * 1103515245 + 12345) % 2147483648) / 2147483648)
    const start = Date.UTC(2024, 8, 12)
    const out: Day[] = []
    let price = 148
    for (let i = 0; i < 730; i += 1) {
      const prev = price
      price = Math.max(40, price + (rnd() - 0.48) * 4 + Math.sin(i / 60) * 0.6)
      out.push({
        date: new Date(start + i * 86_400_000).toISOString().slice(0, 10),
        close: Math.round(price * 100) / 100,
        volume: Math.round(600 + rnd() * 900 + Math.abs(price - prev) * 400),
        change: Math.round((price - prev) * 100) / 100,
      })
    }
    return out
  })()

  let zoom = $state<ChartZoomWindow | null>(null)
  let note = $state('Right-click a day for the menu; Ctrl + wheel to zoom, Shift + drag to pan.')

  const price = $derived<ChartSpec>({
    type: 'line',
    title: 'ACME daily close',
    categories: days.map((d) => d.date),
    series: [{ label: 'Close', values: days.map((d) => d.close), marker: 'none', strokeWidth: 1.5, gradient: true, type: 'area' }],
    xType: 'ordinal-time',
    yAxis: { formatter: (v) => `$${v}` },
    height: 260,
  })
  const volume = $derived<ChartSpec>({
    type: 'bar',
    categories: days.map((d) => d.date),
    series: [{ label: 'Volume', values: days.map((d) => d.volume), colors: days.map((d) => (d.change < 0 ? '#ef4444' : '#16a34a')) }],
    xType: 'ordinal-time',
    yAxis: { formatter: (v) => `${(v / 1000).toFixed(1)}k` },
    height: 150,
  })

  // The grid shows the rows in the window, newest first.
  const visibleRows = $derived(zoom ? days.slice(zoom.i0, zoom.i1 + 1) : days)
  const columns: GridColumns<Day> = [
    { field: 'date', header: 'Date', width: 110 },
    { field: 'close', header: 'Close', width: 90, align: 'right', cell: (c) => `$${(c.getValue() as number).toFixed(2)}` },
    { field: 'change', header: 'Change', width: 90, align: 'right', cell: (c) => { const v = c.getValue() as number; return `${v > 0 ? '+' : ''}${v.toFixed(2)}` } },
    { field: 'volume', header: 'Volume', width: 90, align: 'right' },
  ]

  // ---- Animated, selectable bars.
  const weekdays = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
  let orders = $state([42, 55, 61, 48, 70, 33, 21])
  let picked = $state<ChartPointRef[]>([])
  const shuffle = () => (orders = orders.map((v) => Math.max(8, Math.round(v + (Math.random() - 0.5) * 40))))
  const ordersSpec = $derived<ChartSpec>({
    type: 'bar',
    categories: weekdays,
    series: [{ label: 'Orders', values: orders }],
    height: 220,
  })

  // ---- Drillable sunburst.
  const salesTree = {
    name: 'Sales',
    children: [
      { name: 'EMEA', children: [
        { name: 'UK', children: [{ name: 'London', value: 62 }, { name: 'Manchester', value: 21 }] },
        { name: 'DE', value: 88 }, { name: 'FR', value: 54 }, { name: 'ES', value: 31 },
      ] },
      { name: 'Americas', children: [
        { name: 'US', children: [{ name: 'East', value: 120 }, { name: 'West', value: 96 }, { name: 'Central', value: 44 }] },
        { name: 'CA', value: 38 }, { name: 'BR', value: 27 },
      ] },
      { name: 'APAC', children: [{ name: 'JP', value: 71 }, { name: 'AU', value: 33 }, { name: 'SG', value: 19 }] },
    ],
  }
  let drillPath = $state<string[]>([])
  const sunburst: ChartSpec = { type: 'sunburst', categories: [], series: [], tree: salesTree, height: 300 }
</script>

<section class="wrap">
  <header class="chrome">
    <span class="note">{note}</span>
  </header>

  <div class="body">
    <div class="pane pane-charts">
      <div class="demo-price">
        <SvChart
          spec={price}
          syncGroup="ticker"
          zoomable={{ wheel: 'modifier', pinch: true, pan: true }}
          rangePresets
          bind:zoom
          legend={false}
          animate={{ enter: 'wipe' }}
          contextMenu={(at) => [
            {
              label: at.category ? `Explain ${at.category}` : 'Explain this chart',
              onSelect: () => {
                const d = at.index != null ? days[at.index] : null
                note = d ? `${d.date}: closed at $${d.close} (${d.change > 0 ? '+' : ''}${d.change}) on ${d.volume} shares.` : 'Two years of daily closes.'
              },
            },
          ]}
        />
      </div>
      <div class="demo-volume">
        <SvChart spec={volume} syncGroup="ticker" zoomable legend={false} toolbar={false} tooltipPosition="top-right" tooltipSticky />
      </div>
    </div>
    <div class="grid-host">
      <div class="grid-title">
        {visibleRows.length} of {days.length} days
        {#if zoom}<span class="muted">({days[zoom.i0]?.date} to {days[zoom.i1]?.date})</span>{/if}
      </div>
      <SvGrid data={visibleRows} {columns} {features} sortable rowHeight={26} containerHeight="100%" fitColumns responsive />
    </div>
  </div>

  <div class="row">
    <div class="pane demo-orders">
      <div class="bar">
        <button type="button" class="btn" onclick={shuffle}>New data</button>
        <span class="note">
          {picked.length ? `Selected: ${picked.map((p) => p.category).join(', ')}` : 'Bars grow in, slide on every update, and select on click (Ctrl adds).'}
        </span>
      </div>
      <SvChart spec={ordersSpec} animate={{ enter: 'grow', duration: 600 }} selectable="multi" bind:selected={picked} legend={false} />
    </div>
    <div class="pane demo-sunburst">
      <div class="bar">
        <span class="note">
          {drillPath.length ? `Drilled into ${drillPath.join(' / ')}` : 'Click a region to drill in; the breadcrumb climbs back.'}
        </span>
      </div>
      <SvChart spec={sunburst} drillable bind:drillPath legend={false} />
    </div>
  </div>
</section>

<style>
  .wrap {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
    gap: 10px;
    overflow: auto;
  }
  .chrome {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    flex: none;
  }
  .note,
  .muted {
    font-size: 12px;
    color: var(--sg-muted, #64748b);
  }
  .body,
  .row {
    display: flex;
    flex: none;
    gap: 12px;
    min-height: 0;
  }
  .pane {
    border: 1px solid var(--sg-border, #e2e8f0);
    border-radius: 10px;
    background: var(--sg-bg, #fff);
    padding: 8px 10px;
    min-width: 0;
  }
  .pane-charts {
    flex: 1 1 62%;
  }
  .grid-host {
    flex: 1 1 38%;
    min-width: 0;
    min-height: 260px;
    display: flex;
    flex-direction: column;
  }
  .grid-title {
    font-size: 12px;
    font-weight: 600;
    color: var(--sg-fg, #0f172a);
    padding: 0 0 6px;
  }
  .row > .pane {
    flex: 1 1 50%;
  }
  .bar {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 4px;
  }
  .btn {
    font: inherit;
    font-size: 12px;
    border: 1px solid var(--sg-border, #e2e8f0);
    border-radius: 6px;
    background: var(--sg-bg, #fff);
    color: var(--sg-fg, #0f172a);
    padding: 3px 10px;
    cursor: pointer;
  }
  @media (max-width: 720px) {
    .body,
    .row {
      flex-direction: column;
    }
  }
</style>
```

[View this example on GitHub](https://github.com/sv-grid/sv-grid/blob/main/examples/src/demos/436-chart-sync-zoom.svelte)