void ShuffleBin(string path)
{
using(FileStream fs = new FileStream(path, FileMode.Open, FileAccess.ReadWrite)) {
CloudStream.Reader reader = new CloudStream.Reader(fs);
CloudStream.Writer writer = new CloudStream.Writer(fs);
byte[] tmp_i = new byte[CloudStream.pointRecSize] , tmp_j = new byte[CloudStream.pointRecSize];
ShuffleUtility.WithSwap((int)fs.Length / CloudStream.pointRecSize,
(i, j) => {
reader.SeekPoint(i);
tmp_i = reader.ReadBytes( tmp_i.Length);
reader.SeekPoint(j);
tmp_j = reader.ReadBytes( tmp_j.Length);
writer.SeekPoint(j);
writer.Write(tmp_i);
writer.SeekPoint(i);
writer.Write(tmp_j);
});
}
}
void ShuffleSlicesAndSample(string bin_path)
{
using (FileStream stream = File.Open( bin_path, FileMode.Open)) {
CloudStream.Reader reader = new CloudStream.Reader(stream);
try {
foreach(Slice slice in prog.Iterate(iCloud.slices)) {
int byteCount = slice.size * CloudStream.pointRecSize;
byte[] sliceBytes = new byte[byteCount];
reader.SeekPoint(slice.offset, SeekOrigin.Begin);
stream.Read( sliceBytes, 0, byteCount );
byte[] tmp = new byte[CloudStream.pointRecSize];
ShuffleUtility.WithSwap(slice.size, (i, j) =>
{
/*
* This is the fastest way I found to swap 16-byte long chunks in memory (tried MemoryStream and
* byte-by-byte swap loop).
*/
System.Buffer.BlockCopy(sliceBytes, i * CloudStream.pointRecSize, tmp, 0, CloudStream.pointRecSize);
System.Buffer.BlockCopy(sliceBytes, j * CloudStream.pointRecSize, sliceBytes, i * CloudStream.pointRecSize, CloudStream.pointRecSize);
System.Buffer.BlockCopy(tmp, 0, sliceBytes, j * CloudStream.pointRecSize, CloudStream.pointRecSize);
// 'i' runs backwards from pointCount-1 to 0
});
reader.SeekPoint(slice.offset, SeekOrigin.Begin);
stream.Write( sliceBytes, 0, byteCount );
// may be sample
CloudStream.Reader mem = new CloudStream.Reader(new MemoryStream(sliceBytes));
int sampleSize = Math.Min( sliceSampleSize, (int)mem.PointCount );
mem.DecodePoints(meshConv, sampleSize );
}
} finally {
prog.Done("Shuffled orig bin in {tt}");
}
} // using(stream)
}