# Overlapping areas

> A few volumes, seen through each other. Sample data: daily spot volume on three venues, Sep 10 to Oct 9.

- Type 013 · Change over time
- Component: `<OverlappingAreas>`, the same name as the Figma component
- Install: `npx shadcn add @chartory/overlapping-areas` (free in Hearth: the public registry, no token; Signal with Code and Complete)
- Type page: https://usechartory.com/charts/overlapping-areas

## Installation

1. **Set up the registry once.** This chart is free in Hearth and MIT licensed: no token. Add @chartory to components.json once (the URL alone, no headers), or skip this when another chart is already installed. [Installation guide](https://usechartory.com/docs/installation)

2. **Add the chart.** One command adds the Overlapping areas component to your project.

```bash
npx shadcn add @chartory/overlapping-areas
```

3. **Use it.** Pass your rows. The props are the Figma properties.

usage.tsx:

```tsx
import { OverlappingAreas }
  from "@/components/chartory/overlapping-areas"

<OverlappingAreas
  data={venueVolume}
  size="m"
  legend
/>
```

## Props

### `<OverlappingAreas>`

Every prop but data is a Figma property with the same name and values.

| Prop | Type | Default | Note |
| --- | --- | --- | --- |
| data | OverlappingAreasData | Required | The chart's data. The tables below list every field. |
| size | "xs" \| "s" \| "m" \| "l" | "m" | The size class. Each one is laid out again from the data. |
| legend | boolean | true | Shows the legend row under the plot. |

### OverlappingAreasData

The data prop: one object for the whole chart.

| Prop | Type | Default | Note |
| --- | --- | --- | --- |
| min | number | Required | The bottom of the value scale. |
| max | number | Required | The top of the value scale. |
| ticks | string[] | Required | The axis tick labels. |
| xl | Record<number, string> | Required | The x axis labels, by index. |
| series | OverlappingAreasSeries[] | Required | One entry per series. |
| area? | number | — | Area opacity under each line (none when absent). |
| sw? | number | 2 | The line width. |

### OverlappingAreasSeries

One object per entry in series.

| Prop | Type | Default | Note |
| --- | --- | --- | --- |
| name | string | Required | The name shown on the chart. |
| tok | string | Required | The colour token, e.g. "data/primary". |
| vals | number[] | Required | The values, in order. |

## Overlapping areas chart: a React and Figma chart in four sizes

### What does an overlapping areas chart show?

An overlapping areas chart draws two or three filled series on one axis with see-through fills, so you can compare their levels without stacking them. Where one rises above another, you see it. Use it for venues, channels or regions that run side by side.

Chartory ships it as a Figma component and a React component with the same name. The code installs from the shadcn registry with one command and lands in your project as a file you own.

### What is the Overlapping areas component?

It is one **<OverlappingAreas>** component. Its props are the Figma properties with the same names and values, and the props table above lists them. The data is two or three series, one value per point.

Sizes **XS**, **S**, **M** and **L** re-lay the chart out from the data instead of scaling it, so labels stay readable at every size.

### When should I use it?

- **Are there three series or fewer?** Yes means the overlapping areas fit.
- **Is each series its own level?** Yes means the overlapping areas fit.
- **Do the levels matter, not only the trend?** Yes means the overlapping areas fit.

### When does another type fit better?

- **More fills turn to mud.** Use Multi-line chart instead.
- **The series add up to a total.** Use Streamgraph instead.
- **Only direction and crossings matter.** Use Multi-line chart instead.

## Overlapping areas questions

### Does the Overlapping areas chart work with shadcn/ui?

Yes. It installs through the shadcn registry with the shadcn CLI, and the file lands in your project.

### How do I install it?

It is free in Hearth and MIT licensed: add the @chartory registry URL once, no token, then run npx shadcn add @chartory/overlapping-areas. The Installation guide has the steps.

### Can my coding agent install it?

Yes. Connect the Chartory MCP server and ask for the overlapping areas chart; the agent runs the same command and you review the diff.

### What data does it expect?

Two or three series, one value per point. The sample data comes with the component, and the props table lists every field.

### Which sizes does it ship in?

XS, S, M and L, in Figma and in code. Each size is laid out again from the data, so text and lines keep their size.

### Is it in the Figma file too?

Yes. chart/013-overlapping-areas has the same properties as the component.

### Does it follow light and dark mode?

Yes. Every paint is a token, so the chart follows light and dark mode and the collection you pick.

### Which plan has the code?

None for Hearth: it is free in the public registry, no token. The Signal collection (@chartory/signal) comes with Code and Complete.