GeoJsonVT 瓦片

L7In addition to the tile services provided by the backend, vector tiles also providegeojson-vtThe tile slicing scheme allows the front end to use vector tiles without back-end support.

Vector Tiles - GeoJsonVT

import { PolygonLayer } from '@antv/l7';
fetch('https://gw.alipayobjects.com/os/bmw-prod/2b7aae6e-5f40-437f-8047-100e9a0d2808.json')
  .then((d) => d.json())
  .then((data) => {
    const source = new Source(data, {
      parser: { type: 'geojsonvt', maxZoom: 9 },
    });
    const polygon = new PolygonLayer({ featureId: 'COLOR' }).source(source).color('red');
  });

sourceLayer

When using front-end tile segmentation, we no longer need to specify a data source for the tile layer.

source(GeoJsonData: string, option: IOption)

When using vector tiles split by front-end tiles,sourceThe method receives not the address of the data service, but the standardGeoJSONdata.

option

When using front-end tile segmentation we need tosource parserThe type is set togeojsonvt。

const source = new Source(data, {
  parser: {
    type: 'geojsonvt',
    maxZoom: 9,
    geojsonvtOptions: {},
  },
});

geojsonOptionsThe following parameters are supported: