explode function

FeatureCollection<Point> explode(GeoJSONObject geojson)

Takes a feature or set of features and returns all positions as Points. Takes GeoJSONObhect input. Returns FeatureCollection<point> representing the exploded input features Throws Exception if it encounters an unknown geometry type

var polygon = Polygon(coordinates:
[[
  Position.of([-81, 41]),
  Position.of([-88, 36]),
  Position.of([-84, 31]),
  Position.of([-80, 33]),
  Position.of([-77, 39]),
  Position.of([-81, 41]),
 ]]);

FeatureCollection<Point> explode = explode(polygon);

//addToMap
var addToMap = [polygon, explode]

Implementation

FeatureCollection<Point> explode(GeoJSONObject geojson) {
  var points = <Feature<Point>>[];
  if (geojson is FeatureCollection) {
    featureEach(geojson, (feature, id) {
      coordEach(feature, (Position? currentCoord, int? coordIndex,
          int? featureIndex, int? multiFeatureIndex, int? geometryIndex) {
        points.add(
          Feature(
            geometry: Point(coordinates: currentCoord!),
            properties: Map.of(feature.properties ?? {}),
          ),
        );
      });
    });
  } else if (geojson is Feature) {
    coordEach(geojson, (Position? currentCoord, int? coordIndex,
        int? featureIndex, int? multiFeatureIndex, int? geometryIndex) {
      points.add(
        Feature(
          geometry: Point(coordinates: currentCoord!),
          properties: Map.of(geojson.properties ?? {}),
        ),
      );
    });
  }
  return FeatureCollection(features: points);
}