private BackgroundImage InitBackgroundImageTiles(LatLng[] allLocations)
{
var zoom = MAX_ZOOM;
var n = Math.Pow(2, zoom);
var tiles = new Point
{
X = (int)Math.Ceiling(Math.Ceiling(GetXTile(allLocations.Max(l => l.lng), n)) - Math.Floor(GetXTile(allLocations.Min(l => l.lng), n))),
Y = (int)Math.Ceiling(Math.Ceiling(GetYTile(allLocations.Min(l => l.lat), n)) - Math.Floor(GetYTile(allLocations.Max(l => l.lat), n)))
};
while (tiles.X > NUMBER_OF_TILES_FOR_IMAGE_X || tiles.Y > NUMBER_OF_TILES_FOR_IMAGE_Y)
{
zoom--;
n = Math.Pow(2, zoom);
tiles.X = (int)Math.Ceiling(Math.Ceiling(GetXTile(allLocations.Max(l => l.lng), n)) - Math.Floor(GetXTile(allLocations.Min(l => l.lng), n)));
tiles.Y = (int)Math.Ceiling(Math.Ceiling(GetYTile(allLocations.Min(l => l.lat), n)) - Math.Floor(GetYTile(allLocations.Max(l => l.lat), n)));
}
return new BackgroundImage
{
Tiles = tiles,
Zoom = zoom,
N = n
};
}
private async Task<BackgroundImage> GetBackGroundImage(string addressTemplate, LatLng[] allLocations)
{
var backgroundImage = InitBackgroundImageTiles(allLocations);
var topLeft = new Point((int)GetXTile(allLocations.Min(l => l.lng), backgroundImage.N), (int)GetYTile(allLocations.Max(l => l.lat), backgroundImage.N));
var bottomRight = new Point((int)GetXTile(allLocations.Max(l => l.lng), backgroundImage.N), (int)GetYTile(allLocations.Min(l => l.lat), backgroundImage.N));
if (backgroundImage.Tiles.X == 2 && backgroundImage.Tiles.Y == 1)
{
// no need to do anything.
}
else if (backgroundImage.Tiles.X == 1 && backgroundImage.Tiles.Y == 1)
{
backgroundImage.Tiles = new Point(2, 1);
bottomRight.X++;
}
else
{
backgroundImage.Tiles = new Point(NUMBER_OF_TILES_FOR_IMAGE_X, NUMBER_OF_TILES_FOR_IMAGE_Y);
UpdateImageRectangle(ref topLeft, ref bottomRight);
}
backgroundImage.TopLeft = topLeft;
backgroundImage.Image = await CreateSingleImageFromTiles(topLeft, bottomRight, backgroundImage.Zoom, addressTemplate);
return backgroundImage;
}