arc-layer.md

import {ArcLayerDemo} from 'website-components/doc-demos/layers';

ArcLayer

The Arc Layer renders raised arcs joining pairs of source and target points.

import DeckGL from '@deck.gl/react';
import {ArcLayer} from '@deck.gl/layers';

function App({data, viewState}) {
  /**
   * Data format:
   * [
   *   {
   *     inbound: 72633,
   *     outbound: 74735,
   *     from: {
   *       name: '19th St. Oakland (19TH)',
   *       coordinates: [-122.269029, 37.80787]
   *     },
   *     to: {
   *       name: '12th St. Oakland City Center (12TH)',
   *       coordinates: [-122.271604, 37.803664]
   *   },
   *   ...
   * ]
   */
  const layer = new ArcLayer({
    id: 'arc-layer',
    data,
    pickable: true,
    getWidth: 12,
    getSourcePosition: d => d.from.coordinates,
    getTargetPosition: d => d.to.coordinates,
    getSourceColor: d => [Math.sqrt(d.inbound), 140, 0],
    getTargetColor: d => [Math.sqrt(d.outbound), 140, 0],
  });

  return <DeckGL viewState={viewState}
    layers={[layer]}
    getTooltip={({object}) => object && `${object.from.name} to ${object.to.name}`} />;
}

Installation

To install the dependencies from NPM:

npm install deck.gl
# or
npm install @deck.gl/core @deck.gl/layers

import {ArcLayer} from '@deck.gl/layers';
new ArcLayer({});

To use pre-bundled scripts:

<script src="https://unpkg.com/deck.gl@^8.0.0/dist.min.js"></script>
<!-- or -->
<script src="https://unpkg.com/@deck.gl/core@^8.0.0/dist.min.js"></script>
<script src="https://unpkg.com/@deck.gl/layers@^8.0.0/dist.min.js"></script>

new deck.ArcLayer({});

Properties

Inherits from all Base Layer properties.

Render Options

greatCircle (Boolean, optional)

• Default: false

If true, create the arc along the shortest path on the earth surface. This option is only effective with data in the LNGLAT coordinate system.

widthUnits (String, optional)

• Default: 'pixels'

The units of the line width, one of 'meters', 'pixels'. When zooming in and out, meter sizes scale with the base map, and pixel sizes remain the same on screen.

widthScale (Number, optional)

• Default: 1

The scaling multiplier for the width of each line. This prop is a very efficient way to change the width of all objects, comparing to recalculating the width for each object with getWidth.

widthMinPixels (Number, optional)

• Default: 0

The minimum line width in pixels. This prop can be used to prevent the line from getting too thin when zoomed out.

widthMaxPixels (Number, optional)

• Default: Number.MAX_SAFE_INTEGER

The maximum line width in pixels. This prop can be used to prevent the line from getting too thick when zoomed in.

Data Accessors

getSourcePosition (Function, optional)

• Default: object => object.sourcePosition

Method called to retrieve the source position of each object.

getTargetPosition (Function, optional)

• Default: object => object.targetPosition

Method called to retrieve the target position of each object.

getSourceColor (Function|Array, optional)

• Default: [0, 0, 0, 255]

The rgba color is in the format of [r, g, b, [a]]. Each channel is a number between 0-255 and a is 255 if not supplied.

• If an array is provided, it is used as the source color for all objects.
• If a function is provided, it is called on each object to retrieve its source color.

getTargetColor (Function|Array, optional)

• Default [0, 0, 0, 255]

The rgba color at the target, in r, g, b, [a]. Each component is in the 0-255 range.

• If an array is provided, it is used as the target color for all objects.
• If a function is provided, it is called on each object to retrieve its target color.

getWidth (Function|Number, optional)

• Default: 1

The line width of each object, in units specified by widthUnits (default pixels).

• If a number is provided, it is used as the line width for all objects.
• If a function is provided, it is called on each object to retrieve its line width.

getHeight (Function|Number, optional)

• Default: 1

Multiplier of layer height. 0 will make the layer flat.

getTilt (Function|Number, optional)

• Default: 0

Use to tilt the arc to the side if you have multiple arcs with the same source and target positions. In degrees, can be positive or negative (-90 to +90).

Source

modules/layers/src/arc-layer