ContourChart
Read a field, a geometry or a spectrum, with the scale handled for you.
@luc/ui/chartsWhat it shows
Read a sampled scalar field through explicitly supplied contour rings and levels.
Live preview
Iso-rings supplied by the caller over a nine-point sampled surface — the chart traces nothing itself.
<ContourChart
levels={[
{
level: 0.5,
rings: [
[[-0.5, 0], [0, 0.5], [0.5, 0], [0, -0.5], [-0.5, 0]],
[[-1, 0], [0, 1], [1, 0], [0, -1], [-1, 0]],
],
},
{
level: 1,
rings: [
[[-0.95, 0], [0, 0.95], [0.95, 0], [0, -0.95], [-0.95, 0]],
[[-1.9, 0], [0, 1.9], [1.9, 0], [0, -1.9], [-1.9, 0]],
],
},
]}
surface={[
{ x: -1, y: -1, z: 1 },
{ x: 0, y: -1, z: 0 },
{ x: 1, y: -1, z: 1 },
{ x: -1, y: 0, z: 0 },
{ x: 0, y: 0, z: -1 },
{ x: 1, y: 0, z: 0 },
{ x: -1, y: 1, z: 1 },
{ x: 0, y: 1, z: 0 },
{ x: 1, y: 1, z: 1 },
]}
xFormat={{ kind: "number", decimals: 1 }}
yFormat={{ kind: "number", decimals: 1 }}
zFormat={{ kind: "number", decimals: 1 }}
height={340}
ariaLabel="Saddle field"
/>Controls
Height
A chart measures its container, so it always needs a definite height.
State
The surface the chart is in — loading, empty and error are drawn by the component.
Accessible name
A drawing is not readable by a screen reader, so it needs a name that states what it shows.
The same fixture as the live preview above; the controls change how it is drawn, not what it measures.
Code
import { ContourChart } from "@luc/ui/charts";
<ContourChart
levels={[
{
level: 0.5,
rings: [
[[-0.5, 0], [0, 0.5], [0.5, 0], [0, -0.5], [-0.5, 0]],
[[-1, 0], [0, 1], [1, 0], [0, -1], [-1, 0]],
],
},
{
level: 1,
rings: [
[[-0.95, 0], [0, 0.95], [0.95, 0], [0, -0.95], [-0.95, 0]],
[[-1.9, 0], [0, 1.9], [1.9, 0], [0, -1.9], [-1.9, 0]],
],
},
]}
surface={[
{ x: -1, y: -1, z: 1 },
{ x: 0, y: -1, z: 0 },
{ x: 1, y: -1, z: 1 },
{ x: -1, y: 0, z: 0 },
{ x: 0, y: 0, z: -1 },
{ x: 1, y: 0, z: 0 },
{ x: -1, y: 1, z: 1 },
{ x: 0, y: 1, z: 0 },
{ x: 1, y: 1, z: 1 },
]}
xFormat={{ kind: "number", decimals: 1 }}
yFormat={{ kind: "number", decimals: 1 }}
zFormat={{ kind: "number", decimals: 1 }}
height={340}
ariaLabel="Saddle field"
state="ready"
/>Not controllable here
series / rows— The numbers are the caller's; the fixture above is the example.
Copy for an AI agentA specification an agent can act on: the import, the setup, the chosen props, the data contract and the accessibility expectation.
Implement `ContourChart` from Luc UI. It is: Read a field, a geometry or a spectrum, with the scale handled for you.
Import it with: import { ContourChart } from "@luc/ui/charts";
Requires: react ^19.0.0; react-dom ^19.0.0; react-hook-form ^7.0.0 (optional, for @luc/ui/forms/react-hook-form); tailwindcss ^4.0.0; node >= 22 (repository tools). Import the stylesheet once at the app root and wrap the tree in `LucProvider`. Both come from the package that publishes @luc.
Chosen configuration: `height={340}`, `state="ready"`, `ariaLabel="Saddle field"`.
Accessibility: keep the component's own semantics. Do not re-implement its ARIA wiring, do not add roles it does not declare, and make sure every interactive element is reachable and operable from the keyboard with a visible focus state.
Styling: use Luc UI design tokens and the component's own props. Do not restyle with raw colour literals and do not override the component's internal structure with page CSS.
Motion: respect `prefers-reduced-motion`. The component already does, so do not disable it.
Reproduce this state:
```tsx
<ContourChart
levels={[
{
level: 0.5,
rings: [
[[-0.5, 0], [0, 0.5], [0.5, 0], [0, -0.5], [-0.5, 0]],
[[-1, 0], [0, 1], [1, 0], [0, -1], [-1, 0]],
],
},
{
level: 1,
rings: [
[[-0.95, 0], [0, 0.95], [0.95, 0], [0, -0.95], [-0.95, 0]],
[[-1.9, 0], [0, 1.9], [1.9, 0], [0, -1.9], [-1.9, 0]],
],
},
]}
surface={[
{ x: -1, y: -1, z: 1 },
{ x: 0, y: -1, z: 0 },
{ x: 1, y: -1, z: 1 },
{ x: -1, y: 0, z: 0 },
{ x: 0, y: 0, z: -1 },
{ x: 1, y: 0, z: 0 },
{ x: -1, y: 1, z: 1 },
{ x: 0, y: 1, z: 0 },
{ x: 1, y: 1, z: 1 },
]}
xFormat={{ kind: "number", decimals: 1 }}
yFormat={{ kind: "number", decimals: 1 }}
zFormat={{ kind: "number", decimals: 1 }}
height={340}
ariaLabel="Saddle field"
state="ready"
/>
```Usage
The values are prepared by the caller: this component draws the points it is given and computes no statistic of its own, so units, scaling and any summary have to be settled before the data reaches it.
It is drawn by the ECharts engine.
Worked examples with real data are on the family overview: Scientific & mathematical
import { ContourChart } from "@luc/ui/charts";<ContourChart
levels={[
{
level: 0.5,
rings: [
[[-0.5, 0], [0, 0.5], [0.5, 0], [0, -0.5], [-0.5, 0]],
[[-1, 0], [0, 1], [1, 0], [0, -1], [-1, 0]],
],
},
{
level: 1,
rings: [
[[-0.95, 0], [0, 0.95], [0.95, 0], [0, -0.95], [-0.95, 0]],
[[-1.9, 0], [0, 1.9], [1.9, 0], [0, -1.9], [-1.9, 0]],
],
},
]}
surface={[
{ x: -1, y: -1, z: 1 },
{ x: 0, y: -1, z: 0 },
{ x: 1, y: -1, z: 1 },
{ x: -1, y: 0, z: 0 },
{ x: 0, y: 0, z: -1 },
{ x: 1, y: 0, z: 0 },
{ x: -1, y: 1, z: 1 },
{ x: 0, y: 1, z: 0 },
{ x: 1, y: 1, z: 1 },
]}
xFormat={{ kind: "number", decimals: 1 }}
yFormat={{ kind: "number", decimals: 1 }}
zFormat={{ kind: "number", decimals: 1 }}
height={340}
ariaLabel="Saddle field"
/>Data contract
`surface` supplies the sampled grid and `levels` supplies the iso-values; `xFormat`, `yFormat` and `zFormat` describe the three units. The chart does not extrapolate a surface.
Important configuration
Choose levels that cover the observed range, keep the x/y domain explicit, and format the z value with its real unit rather than a bare number.
Guidelines
When not to use
Do not use contours to hide sparse sampling or present interpolated rings as measured values.
Configuration
| Export | Kind | Signature |
|---|---|---|
ContourChart | 16 documented props | ({ levels, surface, xFormat, yFormat, zFormat, labels, title, description, state, height, className, ariaLabel, ariaDescription, onReady, onEvent, eager, }: ContourChartProps) => import("@types/react… |
ContourChart props
Type: ContourChartProps
Values the compiler reads from the declaration.
| Prop | Type | Default | Notes |
|---|---|---|---|
ariaDescription? | string | undefined | — | |
ariaLabel? | string | undefined | — | |
className? | string | undefined | — | |
description? | string | undefined | — | |
eager? | boolean | undefined | — | Create the engine on mount rather than when the surface is approached. |
height? | string | number | undefined | — | |
labels? | boolean | undefined | — | Label the iso lines. Default `true`. |
levels | readonly ContourLevel[] | — | |
onEvent? | ((event: EChartEvent) => void) | undefined | — | |
onReady? | ((chart: EChartsInstance) => void) | undefined | — | |
state? | ChartState | undefined | — | |
surface? | readonly { x: number; y: number; z: number; }[] | undefined | — | The sampled surface, drawn under the lines as a field. |
title? | string | undefined | — | |
xFormat? | ChartFormat | undefined | — | |
yFormat? | ChartFormat | undefined | — | |
zFormat? | ChartFormat | undefined | — |
Accessibility
A chart is a picture of data, so it needs a name that states what it shows, and the numbers must exist as text somewhere on the page — in a table or a written summary — because a drawing is not readable by a screen reader and cannot be copied.
What happens on the server, and when hydration changes it.
Family
Scientific & mathematical
Fields, geometry and spectra for scientific readers.
Related