Description:

vector tile query

Dart Vector Tile Query #
A Dart package to query reverse geocoding on a set of vector tile protobuf files (pbf or mvt).
Using vector tiles that were parsed by dart-vector-tile.
Features:

✅ Get a list of the features closest to a query point.
✅ Get polygons that contain a point (radius=0).

Sample usage #
import 'package:vector_tile_query/vector_tile_query.dart';

List<QueryTile> tiles = [
QueryTile(
tile: await VectorTile.fromPath(path: '../data/13-6525-3847.pbf'),
x: 6525,
y: 3847,
z: 13,
),
QueryTile(
tile: await VectorTile.fromPath(path: '../data/13-6525-3848.pbf'),
x: 6525,
y: 3848,
z: 13,
),
];

ReverseQueryOption option = ReverseQueryOption(
radius: 20,
limit: 10,
geometryTypes: [VectorTileGeomType.POINT],
layers: ['poi', 'housenumber', 'building', 'park'],
dedupe: true,
);

List<double> point = [
106.75985276699066,
10.844338677301536
]; // lon - lat

var result = reverseQuery(point: point, queryTiles: tiles, option: option);
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Result item structure: #
class ResultItem {
GeoJson geoJson; // GeoJson data
VectorTileFeature feature; // Raw vector tile feature data
double distance; // Distance to query point
}
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GeoJson sample data: https://github.com/saigontek/dart-vector-tile#sample-vectortile-raw-decoded-as-json
VectorTileFeature sample data: https://github.com/saigontek/dart-vector-tile#sample-vectortilefeature-as-geojson-decoded

Example use cases: #
Reverse geocoding to find housenumber, road, suburb and city of a point by given a set of satisfy tiles:


1) Find set of specific zooms for specific feature level. (OSM zoom levels)

14: housenumber, poi and road.
13: suburb.
12: city



2) Find map tile xy number from a lon/lat pair and above zoom: https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Lon..2Flat._to_tile_numbers


3) Run a set of query to find satisfy result 🍺



Get polygons that contain a point:

Set query radius to 0. see example code

License

For personal and professional use. You cannot resell or redistribute these repositories in their original state.

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