/// <summary>
///
/// </summary>
/// <param name="prevFrame"></param>
/// <returns></returns>
public byte[] Compress(ref uint prevFrame, out int size)
{
#if DONT_USE_DELTA
size = queue.Last().Data.Length;
return(NetworkEngine.Compress(queue.Last().Data));
#endif
var lastSnapshot = queue.Last();
size = lastSnapshot.Data.Length;
var prevFrameLocal = prevFrame;
var prevSnapshot = queue.SingleOrDefault(s => s.Frame == prevFrameLocal);
if (prevSnapshot == null)
{
prevFrame = 0;
return(NetDeflate.Compress(lastSnapshot.Data));
}
var delta = new byte[lastSnapshot.Data.Length];
var minSize = Math.Min(delta.Length, prevSnapshot.Data.Length);
for (int i = 0; i < minSize; i++)
{
delta[i] = (byte)(lastSnapshot.Data[i] ^ prevSnapshot.Data[i]);
}
if (delta.Length > prevSnapshot.Data.Length)
{
for (int i = minSize; i < delta.Length; i++)
{
delta[i] = lastSnapshot.Data[i];
}
}
return(NetDeflate.Compress(delta));
}