MapLibre/Mapbox vector tiles (MVT) reader/writer library for Swift, together with a tool for working with vector tiles from the command line.
- Load and write Mapnik Vector Tiles from/to disk, data objects or URLs (also handles gzipped input)
- Export options: Zipped, buffered (in pixels or extents), simplified (in meters or extents)
- Can dump a tile as a GeoJSON object
- Supported projections: EPSG:4326, EPSG:3857 or none (uses the tile's coordinate space)
- Fast search (supports indexing), either within a bounding box or with center and radius
- Extract selected layers into a new tile
- Merge two tiles into one
- Can extract some infos from tiles like feature count, etc.
- Powerful command line tool (via Homebrew, documentation below) for working with vector tiles and GeoJSON files
This package requires Swift 5.10 or higher (at least Xcode 14), and compiles on iOS (>= iOS 13), macOS (>= macOS 13), tvOS (>= tvOS 13), watchOS (>= watchOS 6) as well as Linux.
dependencies: [
.package(url: "https://github.com/Outdooractive/mvt-tools", from: "1.8.0"),
],
targets: [
.target(name: "MyTarget", dependencies: [
.product(name: "MVTTools", package: "mvt-tools"),
]),
]
This package uses the gis-tools library, and is being used by the mvt-postgis library, please have a look at them as well.
See the API documentation (via Swift Package Index).
import MVTTools
// Load
let mvtData = Data(contentsOf: URL(fileURLWithPath: "14_8716_8015.vector.mvt"))!
let tile = VectorTile(data: mvtData, x: 8716, y: 8015, z: 14, indexed: .hilbert)!
print(tile.isIndexed)
print(tile.layerNames.sorted())
let tileAsGeoJsonData: Data? = tile.toGeoJson(prettyPrinted: true)
...
let result = tile.query(at: Coordinate3D(latitude: 3.870163, longitude: 11.518585), tolerance: 100.0)
...
import MVTTools
var tile = VectorTile(x: 8716, y: 8015, z: 14)!
var feature = Feature(Point(Coordinate3D(latitude: 3.870163, longitude: 11.518585)))
feature.properties = [
"test": 1,
"test2": 5.567,
"test3": [1, 2, 3],
"test4": [
"sub1": 1,
"sub2": 2
]
]
tile.setFeatures([feature], for: "test")
// Also have a look at ``VectorTile.ExportOptions``
let tileData = tile.data()
...
On macOS you can use a Swift Playground to inspect the MVTTools API such as layerNames
and projection
.
- Load tile using MVTTools
- Inspect the properties of the
VectorTile
You can install the command line tool mvt
either
- with homebrew:
brew install Outdooractive/homebrew-tap/mvt-tools
- or locally to
/usr/local/bin
with./install_mvt.sh
mvt
works with vector tiles or GeoJSON files from local disk or served from a web server.
GeoJSONs can contain a layer name in their Feature properties (default name is vt_layer
), and any resulting GeoJSON will automatically include this property.
This can be controlled with the options --property-name
(or -P
), --disable-input-layer-property
(or -Di
) and --disable-output-layer-property
(or -Do
).
Some commands allow limiting the result to certain layers with --layer
(or -l
), which can be repeated for as many layers as necessary.
# mvt -h
OVERVIEW: A utility for inspecting and working with vector tiles (MVT) and GeoJSON files.
A x/y/z tile coordinate is needed for encoding/decoding vector tiles (MVT).
This tile coordinate can be extracted from the file path/URL if it's either in the form '/z/x/y' or 'z_x_y'.
Tile coordinates are not necessary for GeoJSON input files.
Examples:
- Tests/MVTToolsTests/TestData/14_8716_8015.vector.mvt
- https://demotiles.maplibre.org/tiles/2/2/1.pbf
USAGE: mvt <subcommand>
OPTIONS:
--version Show the version.
-h, --help Show help information.
SUBCOMMANDS:
dump (default) Print the input file (mvt or GeoJSON) as pretty-printed GeoJSON to the console
info Print information about the input file (mvt or GeoJSON)
query Query the features in the input file (mvt or GeoJSON)
merge Merge any number of vector tiles or GeoJSONs
import Import some GeoJSONs into a vector tile
export Export a vector tile as GeoJSON to a file
See 'mvt help <subcommand>' for detailed help.
Print a vector tile or GeoJSON file as pretty-printed GeoJSON.
mvt dump Tests/MVTToolsTests/TestData/14_8716_8015.vector.mvt
{
"type" : "FeatureCollection",
"features" : [
{
"bbox" : [
11.516327261924731,
3.8807821163834175,
11.516590118408191,
3.8815421167424793
],
"properties" : {
"oneway" : 1,
"vt_layer" : "tunnel",
"class" : "motorway"
},
"geometry" : {
"coordinates" : [
...
],
"type" : "LineString"
},
"id" : 1,
"type" : "Feature"
},
...
}
Print some informations about vector tiles/GeoJSONs.
Example 1: Print information about the MVTTools test vector tile at zoom 14, at Yaoundé, Cameroon.
mvt info Tests/MVTToolsTests/TestData/14_8716_8015.vector.mvt
Name | Features | Points | LineStrings | Polygons | Unknown | Version
--------------------+----------+--------+-------------+----------+---------+--------
area_label | 55 | 55 | 0 | 0 | 0 | 2
barrier_line | 4219 | 0 | 4219 | 0 | 0 | 2
bridge | 14 | 0 | 14 | 0 | 0 | 2
building | 5414 | 0 | 0 | 5414 | 0 | 2
building_label | 413 | 413 | 0 | 0 | 0 | 2
...
road | 502 | 1 | 497 | 4 | 0 | 2
road_label | 309 | 0 | 309 | 0 | 0 | 2
Example 2: Inspect a MapLibre vector tile at zoom 2, with an extent showing Norway to India.
mvt info https://demotiles.maplibre.org/tiles/2/2/1.pbf
Name | Features | Points | LineStrings | Polygons | Unknown | Version
-----------+----------+--------+-------------+----------+---------+--------
centroids | 104 | 104 | 0 | 0 | 0 | 2
countries | 113 | 0 | 0 | 113 | 0 | 2
geolines | 4 | 0 | 4 | 0 | 0 | 2
Query a vector tile or GeoJSON file with a search term.
mvt query Tests/MVTToolsTests/TestData/14_8716_8015.vector.mvt "École"
{
"features" : [
{
"bbox" : [
11.537318229675295,
3.8732409490233337,
11.537318229675295,
3.8732409490233337
],
"geometry" : {
"coordinates" : [
11.537318229675295,
3.8732409490233337
],
"type" : "Point"
},
"id" : 51,
"layer" : "building_label",
"properties" : {
"area" : 173.97920227050781,
"name" : "École Maternelle",
"name_de" : "École Maternelle",
"name_en" : "École Maternelle",
"name_es" : "École Maternelle",
"name_fr" : "École Maternelle"
},
"type" : "Feature"
},
...
}
Query a tile with latitude,longitude,radius
.
mvt query Tests/MVTToolsTests/TestData/14_8716_8015.geojson "3.87324,11.53731,1000"
{
"features" : [
{
"bbox" : [
11.529276967048643,
3.8803432426251487,
11.530832648277283,
3.8823074685255259
],
"geometry" : {
"coordinates" : [
...
],
"type" : "LineString"
},
"id" : 48,
"layer" : "road",
"properties" : {
"class" : "driveway",
"oneway" : 0
},
"type" : "Feature"
},
...
}
Merge two or more vector tiles or GeoJSON files in any combination.
# All vector tiles:
mvt merge --output merged.mvt path/to/first.mvt path/to/second.mvt
# All GeoJSON files:
mvt merge --output merged.geojson path/to/first.geojson path/to/second.geojson
# Merge GeoJSON files into a vector tile:
mvt merge --output merged.mvt --output-format mvt path/to/first.geojson path/to/second.geojson
# Merge vector tiles into a GeoJSOn file:
mvt merge --output merged.geojson --output-format geojson path/to/first.mvt path/to/second.mvt
Write a vector tile as GeoJSON to a file.
mvt export --output dumped.geojson --pretty-print Tests/MVTToolsTests/TestData/14_8716_8015.vector.mvt
Create a vector tile from GeoJSON.
mvt import new.mvt -x 8716 -y 8015 -z 14 Tests/MVTToolsTests/TestData/14_8716_8015.geojson
Please create an issue or open a pull request.
brew install protobuf swift-protobuf swiftlint
-
Documentation (!)
-
Tests
-
Decode V1 tiles
-
Locking (when updating/deleting features, indexing)
-
Query option: within/intersects
-
Libraries
-
Vector tiles
-
Sample data for testing:
-
Other code for inspiration:
MIT
Thomas Rasch, Outdooractive