public static AssetHeader ReadAssetHeader(BinaryReader reader)
{
AssetHeader header = new AssetHeader();
header.compression = (AssetCompression)reader.ReadInt32();
header.sizeInBytes = reader.ReadInt64();
header.uncompressedBytes = reader.ReadInt64();
header.assetName = reader.ReadUtf8String();
string typeName = reader.ReadUtf8String();
header.assetType = TypeFinder.FindType(typeName);
return(header);
}
private void ReadHeaders()
{
var stream = GetThreadStream();
stream.Seek(0, SeekOrigin.Begin);
BinaryReader reader = new BinaryReader(stream, Encoding.UTF8, true);
int numberOfAssets = reader.ReadInt32(); // Read number of assets
for (int i = 0; i < numberOfAssets; i++)
{
AssetHeader header = AssetHeader.ReadAssetHeader(reader);
long assetPosition = stream.Position;
assetPositions.Add(header.assetName, assetPosition);
assetHeaders.Add(header.assetName, header);
stream.Seek(header.sizeInBytes, SeekOrigin.Current);
}
}
public Stream GetUncompressedFileStream(string assetName)
{
if (!assetHeaders.ContainsKey(assetName))
{
throw new ArgumentException($"No asset found with name {assetName} in package {assetFile.Name}");
}
AssetHeader header = assetHeaders[assetName];
long position = assetPositions[assetName];
FileStream fs = GetThreadStream();
fs.Seek(position, SeekOrigin.Begin);
var source = new NonClosingFileStreamReaderWrapper(fs, header.sizeInBytes);
//var source = new DeflateStream(stream, CompressionMode.Decompress, true);
//var output = new byte[header.uncompressedBytes];
//MemoryStream outStream = new MemoryStream(output);
//source.CopyTo(outStream);
switch (header.compression)
{
case AssetCompression.NotCompressed:
return(source);
break;
case AssetCompression.Deflate:
return(new DeflateStream(source, CompressionMode.Decompress, true));
break;
case AssetCompression.Gzip:
return(new GZipStream(source, CompressionMode.Decompress, true));
break;
default:
throw new ArgumentOutOfRangeException();
}
}