public byte[] CompressChunk(Chunk chunk)
{
int numBlocks = (chunk.Uncompressed.Length + maxBlockSize - 1) / maxBlockSize;
if (numBlocks > 8)
{
throw new FormatException("Maximum block number exceeded");
}
ChunkHeader head = new ChunkHeader();
head.magic = -1641380927;
head.blocksize = maxBlockSize;
head.uncompressedsize = chunk.Uncompressed.Length;
int pos = 0;
MemoryStream mem = new MemoryStream();
List <Block> blockList = new List <Block>();
int startData = 16 + 8 * numBlocks;
mem.Seek(startData, SeekOrigin.Begin);
for (int i = 0; i < numBlocks; i++)
{
Block block = new Block();
byte[] result, temp;
if (i != numBlocks - 1)
{
block.uncompressedsize = maxBlockSize;
temp = new byte[maxBlockSize];
}
else
{
block.uncompressedsize = head.uncompressedsize - pos;
temp = new byte[block.uncompressedsize];
}
Buffer.BlockCopy(chunk.Uncompressed, pos, temp, 0, temp.Length);
result = LZO1X.Compress(temp);
if (result.Length == 0)
{
throw new Exception("LZO compression error!");
}
block.compressedsize = result.Length;
mem.WriteBytes(result);
blockList.Add(block);
pos += maxBlockSize;
}
head.compressedsize = (int)mem.Length;
mem.Seek(0, SeekOrigin.Begin);
mem.WriteValueS32(head.magic);
mem.WriteValueS32(head.blocksize);
mem.WriteValueS32(head.compressedsize);
mem.WriteValueS32(head.uncompressedsize);
foreach (Block block in blockList)
{
mem.WriteValueS32(block.compressedsize);
mem.WriteValueS32(block.uncompressedsize);
}
return(mem.ToArray());
}
/// <summary>
/// Takes regular image data and returns it in a compressed form ready for archiving
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public byte[] CompressTex(byte[] data)
{
int chunkSize = 131072; //Set at this stage. Easy to change later
int noChunks = (data.Length + chunkSize - 1) / chunkSize;
CompressedChunkBlock[] chunks = new CompressedChunkBlock[noChunks];
int pos = 0;
for (int i = 0; i < noChunks; i++)
{
if (data.Length - (pos + chunkSize) < 0)
{
chunks[i].uncSize = data.Length - pos;
chunks[i].rawData = new byte[chunks[i].uncSize];
Buffer.BlockCopy(data, pos, chunks[i].rawData, 0, chunks[i].uncSize);
pos += chunks[i].uncSize;
}
else
{
chunks[i].uncSize = chunkSize;
chunks[i].rawData = new byte[chunkSize];
Buffer.BlockCopy(data, pos, chunks[i].rawData, 0, chunkSize);
pos += chunks[i].uncSize;
}
}
pos = 0;
CompressedChunkBlock[] newChunks = new CompressedChunkBlock[noChunks];
for (int i = 0; i < noChunks; i++)
{
newChunks[i].rawData = LZO1X.Compress(chunks[i].rawData);
if (newChunks[i].rawData.Length == 0)
{
throw new Exception("LZO compression failed!");
}
newChunks[i].cprSize = newChunks[i].rawData.Length;
newChunks[i].uncSize = chunks[i].uncSize;
pos += newChunks[i].cprSize;
}
byte[] result;
using (MemoryStream stream = new MemoryStream())
{
byte[] magic = new byte[] { 0xC1, 0x83, 0x2A, 0x9E, 0x00, 0x00, 0x02, 0x00 };
pos = Gibbed.IO.NumberHelpers.LittleEndian(pos);
BinaryWriter bin = new BinaryWriter(stream);
bin.Write(magic);
bin.Write(pos);
pos = Gibbed.IO.NumberHelpers.LittleEndian(data.Length); //unc size
bin.Write(pos);
for (int i = 0; i < noChunks; i++)
{
int uncSize = newChunks[i].uncSize;
int cprSize = newChunks[i].cprSize;
uncSize = Gibbed.IO.NumberHelpers.LittleEndian(uncSize);
cprSize = Gibbed.IO.NumberHelpers.LittleEndian(cprSize);
bin.Write(cprSize);
bin.Write(uncSize);
}
for (int i = 0; i < noChunks; i++)
{
bin.Write(newChunks[i].rawData);
}
result = stream.ToArray();
}
return(result);
}
