public static byte[] Encode(byte[] source, int format)
{
var dest = new byte[source.Length * 2];
var src = new MemoryFile(source);
int w = 0;
while (!src.Eof)
{
var cb_in = (short)Math.Min(src.Remaining, 8192);
var chunk_in = src.Read(cb_in);
var chunk_out = format == 80 ? Format80.Encode(chunk_in) : EncodeSection(chunk_in);
uint cb_out = (ushort)chunk_out.Length;
Array.Copy(BitConverter.GetBytes(cb_out), 0, dest, w, 2);
w += 2;
Array.Copy(BitConverter.GetBytes(cb_in), 0, dest, w, 2);
w += 2;
Array.Copy(chunk_out, 0, dest, w, chunk_out.Length);
w += chunk_out.Length;
}
Array.Resize(ref dest, w);
return(dest);
}
public static int DecodeInto(byte[] src, byte[] dest)
{
VirtualFile ctx = new MemoryFile(src);
int destIndex = 0;
while (true)
{
byte i = ctx.ReadByte();
if ((i & 0x80) == 0)
{
// case 2
byte secondByte = ctx.ReadByte();
int count = ((i & 0x70) >> 4) + 3;
int rpos = ((i & 0xf) << 8) + secondByte;
ReplicatePrevious(dest, destIndex, destIndex - rpos, count);
destIndex += count;
}
else if ((i & 0x40) == 0)
{
// case 1
int count = i & 0x3F;
if (count == 0)
{
return(destIndex);
}
ctx.Read(dest, destIndex, count);
destIndex += count;
}
else
{
int count3 = i & 0x3F;
if (count3 == 0x3E)
{
// case 4
int count = ctx.ReadInt16();
byte color = ctx.ReadByte();
for (int end = destIndex + count; destIndex < end; destIndex++)
{
dest[destIndex] = color;
}
}
else if (count3 == 0x3F)
{
// case 5
int count = ctx.ReadInt16();
int srcIndex = ctx.ReadInt16();
if (srcIndex >= destIndex)
{
throw new NotImplementedException(string.Format("srcIndex >= destIndex {0} {1}", srcIndex, destIndex));
}
for (int end = destIndex + count; destIndex < end; destIndex++)
{
dest[destIndex] = dest[srcIndex++];
}
}
else
{
// case 3
int count = count3 + 3;
int srcIndex = ctx.ReadInt16();
if (srcIndex >= destIndex)
{
throw new NotImplementedException(string.Format("srcIndex >= destIndex {0} {1}", srcIndex, destIndex));
}
for (int end = destIndex + count; destIndex < end; destIndex++)
{
dest[destIndex] = dest[srcIndex++];
}
}
}
}
}
