BruTile / Brutile

	Status
Build
NuGet

News

• 2020 june 7: published a couple of new releases. They are based on just four PRs but because of semver they came out as three separate releases.
  • 2.1.3 with a small fix to allow case insensitive style in wmts.
  • 2.2.0 in which HttpTileSource.PersistentCache now has a setter.
  • 3.0.0 which has two breaking changes.
    • In MbTiles there is a change in the default behavior that some users might notice. Zoom levels are not calculated from the 'tiles' table by default.
    • The TileIndex.Level is now int instead of string. Most users will not notice this unless you write logic around tiling itself.

BruTile

BruTile is a .NET Standard 1.1 library to access tile services like OpenStreetMap and Bing. Such tile services store pre-rendered tiles for a certain area and for various levels of detail. BruTile helps to determine which tiles to fetch for a certain viewport of a map. BruTile returns tiles as raw image streams and has no dependency on a specific client platform. BruTile does not display those tiles. You need to use a mapping library like SharpMap, ArcBruTile or Mapsui or write your own code to display tiles.

What BruTile does is:

1. Helps to construct a tile source, an object that has all information about a tile service.
2. Helps to calculate which tiles you need, given a certain map extent and a map resolution (units per pixel).
3. Helps you fetch those tiles.

BruTile is a .NET Standard library

BruTile 2.0 supports .NET Standard. The Profiles by NuGet package:

All the above libraries additionally target .Net Framework 4.5

Demo

For a demo showing various data sources download the source code and run BruTile.Demo in the Samples folder

Getting Started

1) Create an app and add the BruTile NuGet package

Create a .NET Console app in Visual Studio. The the BruTile NuGet package. Use the package manager tools in Visual Studio or add it from the package manager console:

PM> install-package BruTile 

2) Create a tile source

// This is an example that creates the OpenStreetMap tile source:
var tileSource = new HttpTileSource(new GlobalSphericalMercator(0, 18),
    "http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png",
    new[] {"a", "b", "c"}, "OSM");

3) Calculate which tiles you need

// the extent of the visible map changes but lets start with the whole world
var extent = new Extent(-20037508, -20037508, 20037508, 20037508);
var screenWidthInPixels = 400; // The width of the map on screen in pixels
var resolution = extent.Width / screenWidthInPixels;
var tileInfos = tileSource.Schema.GetTileInfos(extent, resolution);

4) Fetch the tiles from the service

Console.WriteLine("Show tile info");
foreach (var tileInfo in tileInfos)
{
    var tile = tileSource.GetTile(tileInfo);

    Console.WriteLine(
        $"tile col: {tileInfo.Index.Col}, " +
        $"tile row: {tileInfo.Index.Row}, " +
        $"tile level: {tileInfo.Index.Level} , " +
        $"tile size {tile.Length}");
}

Output:

    tile col: 0, tile row: 0, tile level: 1 , tile size 11276
    tile col: 0, tile row: 1, tile level: 1 , tile size 3260
    tile col: 1, tile row: 0, tile level: 1 , tile size 10679
    tile col: 1, tile row: 1, tile level: 1 , tile size 4009

5) Try some of the known tile sources

// You can easily create an ITileSource for a number of predefined tile servers
// with single line statements like:
var tileSource1 = KnownTileSources.Create(); // The default is OpenStreetMap
var tileSource2 = KnownTileSources.Create(KnownTileSource.BingAerial);
var tileSource3 = KnownTileSources.Create(KnownTileSource.BingHybrid);
var tileSource4 = KnownTileSources.Create(KnownTileSource.StamenTonerLite);
var tileSource5 = KnownTileSources.Create(KnownTileSource.EsriWorldShadedRelief);

The predefined tile sources are defined in a single file. Take a look at that file here to learn how you could create any tile source.

6) Use MBTiles, the sqlite format for tile data, to work with tiles stored on your device.

var mbtilesTilesource = new MbTilesTileSource(new SQLiteConnectionString("Resources/world.mbtiles", false));
var mbTilesTile = mbtilesTilesource.GetTile(new TileInfo { Index = new TileIndex(0, 0, 0) });
Console.WriteLine($"This is a byte array of an image file loaded from MBTiles with size: {mbTilesTile.Length}");

Output:

This is a byte array of an image file loaded from MBTiles with size: 27412

The above code can also be found in the BruTile sample called BruTile.GettingStarted in the Samples folder of this repository.

Supported tile service protocols:

• WMTS
• TMS
• OSM (Like TMS with inverted y-axis)
• WMS (tiled requests to a regular WMS)
• ArcGIS Tile Server
• WMS-C

Roadmap

• Stability is currently our primary focus.

Projects that use BruTile

• ArcBruTile a plugin for ArcGIS
• SharpMap a GIS library
• Mapsui a MapComponent for Xamarin.Android. Xamarin.iOS, UWP and WPF
• DotSpatial a GIS library that is used in HydroDesktop

License

Apache 2.0