private async Task <byte[]> CreateMapImageAsync(
int width,
int height,
Models.Bounds boundingBox,
string mediaType,
bool isTransparent,
uint backgroundColor,
IList <string> layerNames)
{
var imageInfo = new SKImageInfo(
width: width,
height: height,
colorType: SKColorType.Rgba8888,
alphaType: SKAlphaType.Premul);
using var surface = SKSurface.Create(imageInfo);
using var canvas = surface.Canvas;
canvas.Clear(new SKColor(backgroundColor));
foreach (var layerName in layerNames)
{
if (this.tileSourceFabric.Contains(layerName))
{
await WmsHelper.DrawLayerAsync( // TODO: ? pass required format to avoid conversions
this.tileSourceFabric.Get(layerName),
width,
height,
boundingBox,
canvas,
isTransparent,
backgroundColor);
}
}
using SKImage image = surface.Snapshot();
if (String.Compare(mediaType, MediaTypeNames.Image.Tiff, StringComparison.OrdinalIgnoreCase) == 0)
{
using var bitmap = SKBitmap.FromImage(image);
// TODO: improve performance of pixels processing, maybe using unsafe/pointers
var pixels = bitmap.Pixels.SelectMany(p => new byte[] { p.Red, p.Green, p.Blue, p.Alpha }).ToArray();
var tiff = ImageHelper.CreateTiffImage(pixels, image.Width, image.Height);
return(tiff);
}
else
{
var imageFormat = U.ImageHelper.SKEncodedImageFormatFromMediaType(mediaType);
using SKData data = image.Encode(imageFormat, 90); // TODO: ? quality parameter
return(data.ToArray());
}
}
public async Task <IActionResult> ProcessWmsRequestAsync(
string service = Identifiers.Wms,
string version = Identifiers.Version111,
string?request = null,
string?layers = null,
////string styles = null,
string?srs = null, // WMS version 1.1.1
string?crs = null, // WMS version 1.3.0
string?bbox = null,
int width = 0,
int height = 0,
string?format = null,
// Optional GetMap request parameters
bool?transparent = false,
string bgcolor = Identifiers.DefaultBackgroundColor,
string exceptions = MediaTypeNames.Application.OgcServiceExceptionXml
////string time = null,
////string sld = null,
////string sld_body = null,
// GetFeatureInfo request parameters
////string query_layers = null,
////string info_format = MediaTypeNames.Text.Plain,
////int x = 0,
////int y = 0,
////int i = 0, // WMS version 1.3.0
////int j = 0, // WMS version 1.3.0
////int feature_count = 1
)
{
//// $"WMS [{Request.GetOwinContext().Request.RemoteIpAddress}:{Request.GetOwinContext().Request.RemotePort}] {Request.RequestUri}";
if (String.Compare(service, Identifiers.Wms, StringComparison.OrdinalIgnoreCase) != 0)
{
var message = $"Unknown service: '{service}' (should be '{Identifiers.Wms}')";
return(ResponseWithExceptionReport(Identifiers.InvalidParameterValue, message, "service"));
}
if ((String.Compare(version, Identifiers.Version111, StringComparison.Ordinal) != 0) &&
(String.Compare(version, Identifiers.Version130, StringComparison.Ordinal) != 0))
{
var message = $"Unsupported {nameof(version)}: {version} (should be one of: {Identifiers.Version111}, {Identifiers.Version130})";
return(ResponseWithExceptionReport(Identifiers.InvalidParameterValue, message, "version"));
}
if ((String.Compare(exceptions, MediaTypeNames.Application.OgcServiceExceptionXml, StringComparison.Ordinal) != 0) &&
(String.Compare(exceptions, "XML", StringComparison.Ordinal) != 0))
{
var message = $"Unsupported {nameof(exceptions)}: {exceptions} (should be {MediaTypeNames.Application.OgcServiceExceptionXml})";
return(ResponseWithExceptionReport(Identifiers.InvalidParameterValue, message, "exceptions"));
}
if (String.Compare(request, Identifiers.GetCapabilities, StringComparison.Ordinal) == 0)
{
return(this.ProcessGetCapabilitiesRequest(WmsHelper.GetWmsVersion(version)));
}
else if (String.Compare(request, Identifiers.GetMap, StringComparison.Ordinal) == 0)
{
return(await this.ProcessGetMapRequestAsync(
version,
layers,
WmsHelper.GetWmsVersion(version) == Wms.Version.Version130?crs : srs,
bbox,
width,
height,
format,
transparent,
bgcolor));
}
////else if (String.Compare(request, Identifiers.GetFeatureInfo, StringComparison.Ordinal) == 0)
////{
////return await this.ProcessGetFeatureInfoRequestAsync(
//// bbox, width,
//// query_layers, info_format,
//// v == Wms.Version.v130 ? i : x,
//// v == Wms.Version.v130 ? j : y,
//// feature_count);
////}
else
{
var message = $"Unsupported request: '{request}' ({Identifiers.GetCapabilities}, {Identifiers.GetMap}, {Identifiers.GetFeatureInfo})";
return(ResponseWithServiceExceptionReport(Identifiers.OperationNotSupported, message, version));
}
}
private async Task <IActionResult> ProcessGetMapRequestAsync(
string version,
string?layers,
string?srs,
string?bbox,
int width,
int height,
string?format,
bool?transparent,
string bgcolor)
{
// TODO: config ?
const int MinSize = 1;
const int MaxSize = 32768;
if (String.IsNullOrEmpty(format))
{
var message = "No map output format was specified";
return(ResponseWithServiceExceptionReport(Identifiers.InvalidFormat, message, version));
}
// TODO: more output formats
var isFormatSupported = U.EntitiesConverter.IsFormatInList(
new[]
{
MediaTypeNames.Image.Png,
MediaTypeNames.Image.Jpeg,
MediaTypeNames.Image.Tiff,
},
format);
if (!isFormatSupported)
{
var message = $"Image output format '{format}' is not supported";
return(ResponseWithServiceExceptionReport(Identifiers.InvalidFormat, message, version));
}
if (String.IsNullOrEmpty(layers))
{
var message = "GetMap request must include a valid LAYERS parameter.";
return(ResponseWithServiceExceptionReport(Identifiers.LayerNotDefined, message, version));
}
if ((width < MinSize) ||
(width > MaxSize) ||
(height < MinSize) ||
(height > MaxSize))
{
var message = $"Missing or invalid requested map size. Parameters WIDTH and HEIGHT must present and be positive integers (got WIDTH={width}, HEIGHT={height}).";
return(ResponseWithServiceExceptionReport(Identifiers.MissingOrInvalidParameter, message, version));
}
if (String.IsNullOrEmpty(srs))
{
var message = $"GetMap request must include a valid {(WmsHelper.GetWmsVersion(version) == Wms.Version.Version130 ? "CRS" : "SRS")} parameter.";
return(ResponseWithServiceExceptionReport(Identifiers.MissingBBox, message, version));
}
// TODO: EPSG:4326 output support
if (String.Compare(srs, Identifiers.EPSG3857, StringComparison.OrdinalIgnoreCase) != 0)
{
var message = $"SRS '{srs}' is not supported, only {Identifiers.EPSG3857} is currently supported.";
return(ResponseWithServiceExceptionReport(Identifiers.InvalidSRS, message, version));
}
if (bbox == null)
{
var message = "GetMap request must include a valid BBOX parameter.";
return(ResponseWithServiceExceptionReport(Identifiers.MissingBBox, message, version));
}
var boundingBox = Models.Bounds.FromCommaSeparatedString(bbox);
if (boundingBox == null)
{
var message = $"GetMap request must include a valid BBOX parameter with 4 coordinates (got '{bbox}').";
return(ResponseWithServiceExceptionReport(null, message, version));
}
if (boundingBox.Right <= boundingBox.Left || boundingBox.Top <= boundingBox.Bottom)
{
var message = $"GetMap request must include a valid BBOX parameter with minX < maxX and minY < maxY coordinates (got '{bbox}').";
return(ResponseWithServiceExceptionReport(null, message, version));
}
var layersList = layers.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
var isTransparent = transparent ?? false;
var backgroundColor = U.EntitiesConverter.GetArgbColorFromString(bgcolor, isTransparent);
var imageData = await this.CreateMapImageAsync(width, height, boundingBox, format, isTransparent, backgroundColor, layersList);
return(File(imageData, format));
}
