public async Task <GetDataResult> TryGetDataAtPoint(double latDegree, double lonDegree, TraceListener log)
{
if (!triedToGetMS)
{
ms = await BlobHelper.TryGetStreamAsync(container, fullFileName, log);
triedToGetMS = true;
}
if (ms == null || !HasDataAtLat(latDegree) || !HasDataAtLon(lonDegree))
{
return(new GetDataResult()
{
Success = false, Data = default(T)
});
}
int i = (int)Math.Round(scaleLat * (latDegree - latLo));
int j = numLon - 1 - (int)Math.Round(scaleLon * (lonDegree - lonLo));
var data = readPixel(ms, i, j);
return(new GetDataResult()
{
Success = true, Data = data
});
}
public static async Task <DeletableFileStream> TryGetStreamAsync(string containerName, string fileName, TraceListener log)
{
var localFileName = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString() + ".tmp");
var cacheFileName = Path.Combine(Path.GetTempPath(), fileName);
foreach (DriveInfo d in DriveInfo.GetDrives().Where(p => p.Name.ToLower()[0] == localFileName.ToLower()[0] && p.IsReady))
{
log?.WriteLine(string.Format("{0} has {1, 15} bytes available", d.Name, d.AvailableFreeSpace));
}
if (!File.Exists(cacheFileName))
{
try
{
CloudBlockBlob blockBlob = (await GetContainerAsync(containerName, log)).GetBlockBlobReference(fileName);
await blockBlob.DownloadToFileAsync(localFileName, FileMode.CreateNew);
}
catch (Exception ex)
{
log?.WriteLine("Missing blob: " + fileName);
log?.WriteLine("Error was:" + ex.ToString());
return(null);
}
var fi = new FileInfo(localFileName);
if (!File.Exists(cacheFileName))
{
fi.CopyTo(cacheFileName);
}
}
else
{
var fi = new FileInfo(cacheFileName);
fi.CopyTo(localFileName);
}
var fs = File.OpenRead(localFileName);
fs.Position = 0;
var ret = new DeletableFileStream(localFileName, fs);
return(ret);
}
private ChunkHolder <T> ReadChunk(DeletableFileStream stream, StandardChunkMetadata template)
{
byte[] buffer = new byte[Math.Max(4, pixelDataSize)];
stream.Read(buffer, 0, 4);
int width = BitConverter.ToInt32(buffer, 0);
stream.Read(buffer, 0, 4);
int height = BitConverter.ToInt32(buffer, 0);
var ret = new ChunkHolder <T>(width, height,
template.LatLo, template.LonLo,
template.LatHi, template.LonHi,
null, toDouble, fromDouble);
for (int i = 0; i < width; i++)
{
for (int j = 0; j < height; j++)
{
ret.Data[i][j] = ReadPixel(stream, buffer);
}
}
return(ret);
}
//protected abstract Task<T> ReadPixel(DeletableFileStream stream, byte[] buffer); protected abstract T ReadPixel(DeletableFileStream stream, byte[] buffer);
// protected override async Task<float> ReadPixel(DeletableFileStream stream, byte[] buffer)
protected override float ReadPixel(DeletableFileStream stream, byte[] buffer)
{
//await stream.ReadAsync(buffer, 0, 4);
stream.Read(buffer, 0, 4);
return(BitConverter.ToSingle(buffer, 0));
}
