toGeoJsonWithExtentCalculated<T extends GeoJson<Geometry>> method

T? toGeoJsonWithExtentCalculated<T extends GeoJson<Geometry>>({ required int x0, required int y0, required int size, })

Get GeoJson data from this feature

x0, y0, size: is tile numbers and tile zoom that already calculated with layer extent x0, y0, size was used to calculate lon/lat pairs

Return generic GeoJson type, there are two ways to to read data returned from this method:

• Explicit given a generic type:

   var geojson = feature.toGeoJson<GeoJsonPoint>(3262, 1923, 12);
   var coordinates = geojson.geometry.coordinates;
  

• Cast to specific GeoJson type after got returned data:

   var geojson = feature.toGeoJson(3262, 1923, 12);
   var coordinates = (geojson as GeoJsonPoint).geometry.coordinates;
  

Implementation

T? toGeoJsonWithExtentCalculated<T extends GeoJson>(
    {required int x0, required int y0, required int size}) {
  if (this.geometry == null) {
    this.decodeGeometry();
  }

  switch (this.geometryType) {
    case GeometryType.Point:
      (this.geometry as GeometryPoint).coordinates = this._projectPoint(
          size, x0, y0, (this.geometry as GeometryPoint).coordinates);

      return GeoJsonPoint(
        geometry: this.geometry,
        properties: this.properties,
      ) as T;
    case GeometryType.MultiPoint:
      (this.geometry as GeometryMultiPoint).coordinates = this._project(
          size, x0, y0, (this.geometry as GeometryMultiPoint).coordinates);

      return GeoJsonMultiPoint(
        geometry: this.geometry,
        properties: this.properties,
      ) as T;
    case GeometryType.LineString:
      (this.geometry as GeometryLineString).coordinates = this._project(
          size, x0, y0, (this.geometry as GeometryLineString).coordinates);

      return GeoJsonLineString(
        geometry: this.geometry,
        properties: this.properties,
      ) as T;

    case GeometryType.MultiLineString:
      (this.geometry as GeometryMultiLineString).coordinates =
          (this.geometry as GeometryMultiLineString)
              .coordinates
              .map((line) => this._project(size, x0, y0, line))
              .toList(growable: false);

      return GeoJsonMultiLineString(
        geometry: this.geometry,
        properties: this.properties,
      ) as T;
    case GeometryType.Polygon:
      (this.geometry as GeometryPolygon).coordinates =
          (this.geometry as GeometryPolygon)
              .coordinates
              .map((line) => this._project(size, x0, y0, line))
              .toList(growable: false);

      return GeoJsonPolygon(
        geometry: this.geometry,
        properties: this.properties,
      ) as T;
    case GeometryType.MultiPolygon:
      (this.geometry as GeometryMultiPolygon).coordinates =
          (this.geometry as GeometryMultiPolygon)
              .coordinates!
              .map((polygon) => polygon
                  .map((ring) => this._project(size, x0, y0, ring))
                  .toList(growable: false))
              .toList(growable: false);

      return GeoJsonMultiPolygon(
        geometry: this.geometry,
        properties: this.properties,
      ) as T;
    default:
  }

  return null;
}