G2

geoPath

G2

geoPath

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geoPath can be used to draw maps in combination with geojson.

Getting Started

import { Chart } from '@antv/g2';
import { feature } from 'topojson';

Promise.all([
  fetch('https://assets.antv.antgroup.com/g2/us-10m.json').then((res) =>
    res.json(),
  ),
  fetch('https://assets.antv.antgroup.com/g2/unemployment2.json').then((res) =>
    res.json(),
  ),
]).then((values) => {
  const [us, unemployment] = values;
  const counties = feature(us, us.objects.counties).features;

  const chart = new Chart({
    container: 'container',
  });

  chart
    .geoPath()
    .projection({ type: 'albersUsa' })
    .data({
      value: counties,
      transform: [
        {
          type: 'join',
          join: unemployment,
          on: ['id', 'id'],
          select: ['rate'],
        },
      ],
    })
    .scale('color', {
      type: 'sequential',
      palette: 'ylGnBu',
      unknown: '#fff',
    })
    .encode('color', 'rate');

  chart.render();
});

For more examples, please visit the Chart Examples page.

Options

Currently, in addition to the same API and configuration options as common marks, geoPath has a special projection mapping. G2 currently has all the mappings from d3-geo built in.

FAQ

How to draw a map of China?

The map is ultimately determined by geojson data, so you need to find a geojson of China's administrative map and apply this data to the current example demo.

chart
  .geoPath()
  .data(geojson)
  .encode('latitude', 'latitude')
  .encode('longitude', 'longitude')
  .encode('color', 'rate');
  .scale('color', {
    type: 'sequential',
    palette: 'ylGnBu',
    unknown: '#fff',
  });

  chart.render();