private async Task <IActionResult> GetTileAsync(string tileset, int tileCol, int tileRow, int tileMatrix, string mediaType)
{
var tileSource = this.tileSourceFabric.Get(tileset);
if (!WebMercator.IsInsideBBox(tileCol, tileRow, tileMatrix, tileSource.Configuration.Srs))
{
return(ResponseWithNotFoundError(Identifiers.NotFound, "The requested tile is outside the bounding box of the tile map."));
}
var data = await tileSource.GetTileAsync(tileCol, WebMercator.FlipYCoordinate(tileRow, tileMatrix), tileMatrix); // In WMTS Y axis goes down from the top
if (data != null && data.Length > 0)
{
if (String.Compare(mediaType, tileSource.Configuration.ContentType, StringComparison.OrdinalIgnoreCase) == 0)
{
return(File(data, mediaType)); // Return original source image
}
else
{
var isFormatSupported = Utils.EntitiesConverter.IsFormatInList(
new[]
{
MediaTypeNames.Image.Png,
MediaTypeNames.Image.Jpeg,
MediaTypeNames.Image.Webp,
},
mediaType);
// Convert source image to requested output format, if possible
if (isFormatSupported)
{
var outputImage = ImageHelper.ConvertImageToFormat(data, mediaType, 90); // TODO: quality parameter
if (outputImage != null)
{
return(File(outputImage, mediaType));
}
else
{
return(ResponseWithNotFoundError(Identifiers.NotFound, "Specified tile was not found"));
}
}
else
{
return(File(data, mediaType)); // Conversion not possible
}
}
}
else
{
return(ResponseWithNotFoundError(Identifiers.NotFound, "Specified tile was not found"));
}
}