private readonly string[] _serverEndpoints = { "a", "b", "c" }; // OSM server addreses
void Awake()
{
// Create a TileRange based on the corner coordinates of the GPX
// track.
_gpxInput.Initialize(_zoom); // initialize _gpxInput obj
var bounds = _gpxInput.ComputeMapCoordinateBounds();
var tiles = new TileRange((int)bounds.minLon, (int)bounds.minLat,
(int)bounds.maxLon, (int)bounds.maxLat,
_zoom);
// init list of tex2D that forms the tiles in the tilemap
var tileTexList = new List <(int X, int Y, Texture2D texture)>();
// system path to save the png OSM tile images and later load them
// from dir
string tilesDataPath = Path.Combine(Application.persistentDataPath,
"Assets/Resources");
// for each tile in the tilerange, download from server and save to
// file or load from file if it already exists/
foreach (var tile in tiles)
{
var random = new System.Random();
var savePath = Path.Combine(tilesDataPath, "Tiles",
$"{_zoom}/{tile.X}/{tile.Y}.png");
if (!File.Exists(savePath))
{
// Download new map tile
var url =
$"http://{_serverEndpoints[random.Next(0, 2)]}.tile.openstreetmap.org/{_zoom}/{tile.X}/{tile.Y}.png";
WebRequests.GetTexture(url,
(string error) =>
{
// Net error.
// Debug.Log("Error: " + error);
}, (Texture2D texture2D) =>
{
// Save Image
ImageLoader.SaveImage(savePath, texture2D.EncodeToPNG());
tileTexList.Add((tile.X, -tile.Y, texture2D));
});