GLTFBinaryExtension constructor

Implementation

GLTFBinaryExtension(ByteBuffer data) {
  name = gltfExtensions["KHR_BINARY_GLTF"]!;
  // final headerView = DataView( data, 0, BINARY_EXTENSION_HEADER_LENGTH );
  final headerView = ByteData.view(data, 0, behl);

  header = {
    "magic": LoaderUtils.decodeText(data.asUint8List(0, 4)),
    "version": headerView.getUint32(4, Endian.host),
    "length": headerView.getUint32(8, Endian.host)
  };

  if (header["magic"] != behm) {
    throw ('GLTFLoader: Unsupported glTF-Binary header.');
  }
  else if (header["version"] < 2.0) {
    throw ('GLTFLoader: Legacy binary file detected.');
  }

  // final chunkView = DataView( data, BINARY_EXTENSION_HEADER_LENGTH );
  ByteData chunkView = ByteData.view(data, behl);
  int chunkIndex = 0;

  while (chunkIndex < chunkView.lengthInBytes) {
    final chunkLength = chunkView.getUint32(chunkIndex, Endian.host);
    chunkIndex += 4;

    final chunkType = chunkView.getUint32(chunkIndex, Endian.host);
    chunkIndex += 4;

    if (chunkType == bect["JSON"]) {
      final contentArray = Uint8List.view(
          data, behl + chunkIndex, chunkLength);
      content = LoaderUtils.decodeText(contentArray);
    } else if (chunkType == bect["BIN"]) {
      final byteOffset = behl + chunkIndex;

      body = Uint8List.view(data)
          .sublist(byteOffset, byteOffset + chunkLength)
          .buffer;
    }

    // Clients must ignore chunks with unknown types.

    chunkIndex += chunkLength;
  }

  if (content == null) {
    throw ('THREE.GLTFLoader: JSON content not found.');
  }
}