# HighLow Layer

Variable rendered as highs/lows

### Example

![HighLow Layer](/files/J0165HkqmarXppQ0r3ue)

```javascript
import { Deck } from '@deck.gl/core';
import * as WeatherLayers from 'weatherlayers-gl';

// load data
const image = await WeatherLayers.loadTextureData(url);

const deckgl = new Deck({
  layers: [
    new WeatherLayers.HighLowLayer({
      id: 'highLow',
      // data properties
      image: image,
      bounds: [-180, -90, 180, 90],
      // style properties
      radius: 1000, // km
    }),
  ],
});
```

### Data Properties

See [Data properties](/weatherlayers-gl/layers/data.md#data-properties) common for all layers.

### Style Properties

See [Style properties](/weatherlayers-gl/layers/style-properties.md) common for all layers.

#### `radius`

Type: number, required

Radius in km to filter nearby values. The greater radius, the less values are detected.

#### `unitFormat`

Type: [`UnitFormat`](/weatherlayers-gl/types.md#unitformat), optional

Default: `null`

Unit definition to be used for formatting numbers.

#### `textFormatFunction`

Type: function `(value: number, unitFormat: UnitFormat) => string`, optional

Default: `(value, unitFormat) => unitFormat ? formatValue(value, unitFormat) : Math.round(value).toString()`

Function to format the value.

#### `textFontFamily`

Type: string, optional

Default: `"Helvetica Neue", Arial, Helvetica, sans-serif`

Font family of the text. See [TextLayer fontFamily](https://deck.gl/docs/api-reference/layers/text-layer#fontfamily).

#### `textSize`

Type: number, optional

Default: `12`

Size of the text. See [TextLayer getSize](https://deck.gl/docs/api-reference/layers/text-layer#getsize).

#### `textColor`

Type: color `[number, number, number, number?]`, optional

Default: `[255, 255, 255]`

Color of the text. See [TextLayer getColor](https://deck.gl/docs/api-reference/layers/text-layer#getcolor).

#### `textOutlineWidth`

Type: number, optional

Default: `1`

Width of outline around the text, relative to the font size. See [TextLayer outlineWidth](https://deck.gl/docs/api-reference/layers/text-layer#outlinewidth).

#### `textOutlineColor`

Type: color `[number, number, number, number?]`, optional

Default: `[13, 13, 13]`

Color of outline around the text. See [TextLayer outlineColor](https://deck.gl/docs/api-reference/layers/text-layer#outlinecolor).

#### `palette`

Type: color palette text or array, optional

Palette used to interpolate values to colors.

Formats:

* text (`string`) - see [Text format](https://github.com/weatherlayers/cpt2js#text-format) for details
* array (`[number, PaletteColor][]`) - `PaletteColor` is any object accepted by [Chroma.js constructor](https://vis4.net/chromajs/#chroma)


---

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