public Scene Read()
{
//The 12-byte header consists of three 4-byte entries:
_header = new GlbHeader();
//magic equals 0x46546C67. It is ASCII string glTF, and can be used to identify data as Binary glTF.
_header.Magic = _stream.ReadUInt <LittleEndianConverter>();
//version indicates the version of the Binary glTF container format. This specification defines version 2.
_header.Version = _stream.ReadUInt <LittleEndianConverter>();
//length is the total length of the Binary glTF, including Header and all Chunks, in bytes.
_header.Length = _stream.ReadUInt <LittleEndianConverter>();
if (_header.Version != 2)
{
throw new NotImplementedException($"Version {_header.Version} not implemented");
}
//Chunk 0 Json
uint jsonChunkLength = _stream.ReadUInt <LittleEndianConverter>();
string jsonChunkType = _stream.ReadString(4);
if (jsonChunkType != "JSON")
{
throw new GltfReaderException("Chunk type does not match", _stream.Position);
}
_root = JsonConvert.DeserializeObject <GltfRoot>(_stream.ReadString((int)jsonChunkLength));
//Chunk 1 bin
uint binChunkLength = _stream.ReadUInt <LittleEndianConverter>();
string binChunkType = _stream.ReadString(4);
//Check the chunk type
if (binChunkType != "BIN\0")
{
throw new GltfReaderException("Chunk type does not match", _stream.Position);
}
byte[] binChunk = _stream.ReadBytes((int)binChunkLength);
_binaryStream = new StreamIO(binChunk);
return(GltfBinaryReaderBase.GetBynaryReader((int)_header.Version, _root, binChunk).Read());
}
protected List <T> readAccessor <T>(StreamIO stream, GltfAccessor.ComponentTypeEnum componentType, int count, int nargs)
{
List <T> vecs = new List <T>();
for (int i = 0; i < count; i++)
{
List <object> args = new List <object>();
for (int j = 0; j < nargs; j++)
{
switch (componentType)
{
case GltfAccessor.ComponentTypeEnum.BYTE:
case GltfAccessor.ComponentTypeEnum.UNSIGNED_BYTE:
args.Add(stream.ReadByte());
break;
case GltfAccessor.ComponentTypeEnum.SHORT:
args.Add(stream.ReadShort());
break;
case GltfAccessor.ComponentTypeEnum.UNSIGNED_SHORT:
args.Add(stream.ReadUShort());
break;
case GltfAccessor.ComponentTypeEnum.UNSIGNED_INT:
args.Add(stream.ReadUInt());
break;
case GltfAccessor.ComponentTypeEnum.FLOAT:
args.Add(stream.ReadSingle());
break;
default:
throw new Exception();
}
}
vecs.Add((T)Activator.CreateInstance(typeof(T), args.ToArray()));
}
return(vecs);
}