/// <summary>
/// Read a mesh from the specified stream
/// </summary>
/// <param name="mesh"></param>
/// <param name="stream"></param>
/// <param name="config"></param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
public static void ReadInto(Mesh mesh, Stream stream, FileConfig config = null)
{
if (config == null)
{
config = FileConfig.DefaultConfig();
}
//we're not wrapping the reading into a using because we don't want it to close the stream when done
var reader = new BinaryReader(stream);
var sigBytes = reader.ReadBytes(3);
var sigString = Iso8859.GetString(sigBytes);
if (sigString != FILE_SIGNATURE)
{
throw new Exception("Stream did not have the UNM file signature");
}
//TODO: care about the version
var version = reader.ReadByte();
if (version != VERSION)
{
throw new Exception(string.Format("Version {0} cannot read file version {1}", VERSION, version));
}
var chunkCount = reader.ReadInt32();
for (int i = 0; i < chunkCount; i++)
{
ushort chunkID;
try
{
chunkID = reader.ReadUInt16();
}
catch (EndOfStreamException)
{
//no more chunks
break;
}
var chunkLength = (int)reader.ReadUInt32();
var chunkBytes = new byte[chunkLength];
var chunkReadBytes = stream.Read(chunkBytes, 0, chunkLength);
if (chunkReadBytes < chunkLength)
{
Debug.LogError(
string.Format(
"[UnityMesh] Stream ended unexpectedly. Expected {0} bytes, read only {1} bytes. Chunk ID {2}",
chunkLength, chunkReadBytes, chunkID));
break;
}
Chunk chunk;
if (config.TryGetChunk(chunkID, out chunk))
{
try
{
chunk.Read(chunkBytes, mesh);
}
catch (Exception e)
{
Debug.LogError(string.Format("[UnityMesh] Failed to read chunk {0} : {1}. Skipping.",
chunk.GetType().Name, e));
}
}
else
{
Debug.LogWarning(string.Format("[UnityMesh] Unknown Chunk ID {0}, {1} bytes. Skipping.", chunkID,
chunkLength));
stream.Seek(chunkLength, SeekOrigin.Current);
}
}
}