mapbox-vector-tile-cs

.NET 8 library for decoding a Mapbox vector tile.

Optionally it's possible to convert the tile into a collection of GeoJSON FeatureCollection objects.

For each layer there is one GeoJSON FeatureCollection. Code is tested using the Mapbox tests from

https://github.com/mapbox/vector-tile-js

Dependencies

• GeoJSON.NET

• JSON.NET

• protobuf-net

Installation

$ Install-Package mapbox-vector-tile

Usage

const string vtfile = "vectortile.pbf";
using (var stream = File.OpenRead(vtfile))
{
  // parameters: tileColumn = 67317, tileRow = 43082, tileLevel = 17 
  var layerInfos = VectorTileParser.Parse(stream);
  var fc = layerInfos[0].ToGeoJSON(67317,43082,17);
  Assert.IsTrue(fc.Features.Count == 47);
  Assert.IsTrue(fc.Features[0].Geometry.Type == GeoJSONObjectType.Polygon);
  Assert.IsTrue(fc.Features[0].Properties.Count==2);
}

See also https://github.com/bertt/mapbox-vector-tile-cs/blob/master/tests/mapbox.vector.tile.tests/TileParserTests.cs for working examples

Tip: If you use this library with vector tiles loading from a webserver, you could run into the following exception: 'ProtoBuf.ProtoException: Invalid wire-type; this usually means you have over-written a file without truncating or setting the length' Probably you need to check the GZip compression, see also TileParserTests.cs for an example.

Building

$ git clone https://github.com/bertt/mapbox-vector-tile-cs.git
$ cd mapbox-vector-tile-cs
$ dotnet build

Testing

$ git clone https://github.com/bertt/mapbox-vector-tile-cs.git
$ cd mapbox-vector-tile-cs/tests/mapbox.vector.tile.tests
$ dotnet test
Passed!
Failed: 0, Passed: 38, Skipped: 0, Total: 38, Duration: 937 ms

Benchmarking

Test performed with Mapbox vector tile '14-8801-5371.vector.pbf'

Layers used:

Point layer: parks (id=17) - 558 features

Line layer: roads (id=8) - 686 features

Polygon layer: building (id=5) - 975 features

Host Process Environment Information:
BenchmarkDotNet.Core=v0.9.9.0
OS=Microsoft Windows NT 6.2.9200.0
Processor=Intel(R) Core(TM) i7-6820HQ CPU 2.70GHz, ProcessorCount=8
Frequency=2648440 ticks, Resolution=377.5808 ns, Timer=TSC
CLR=MS.NET 4.0.30319.42000, Arch=32-bit RELEASE
GC=Concurrent Workstation
JitModules=clrjit-v4.6.1586.0

Type=ParsingBenchmark  Mode=Throughput
-------------------------------- |-------------- |-------------|
                          Method |    Median     |    StdDev   |
-------------------------------- |-------------- |-------------|
       ParseVectorTileFromStream |     1.7147 us |   0.0196 us |
 --------------------------------|-------------- |------------ |
   VectorTilePointLayerToGeoJSON |   719.3773 us |   5.7271 us |
    VectorTileLineLayerToGeoJSON | 1,532.6888 us | 114.5458 us |
 VectorTilePolygonLayerToGeoJSON | 4,458.0017 us | 274.7238 us |
-------------------------------- |-------------- |-------------|

History

2023-11-26: Release 5.0.2, containing .NET 8

2022-10-29: Release 5.0.1, upgrading dependencies

2022-10-29: Release 5.0 containing .NET 6

2018-08-28: Release 4.2 containing .NET Standard 2.0

2018-03-08: Release 4.1 with fix for issue 16 (#16 - about serializing attributes)

2017-10-19: Release 4.0 for .NET Standard 1.3

2016-11-03: Release 3.1

Changes: Add support for polygon inner- and outerrings

2016-10-31: Release 3.0

Changes: Add support for multi-geometries

2015-07-08: Release 2.0

2015-07-07: Release 1.0