/// <summary>
/// Read a sequence of raw variables from .mat file.
/// </summary>
/// <param name="reader">Reader.</param>
/// <param name="subsystemDataOffset">Offset of subsystem data in the file;
/// we need it because we may encounter it during reading, and
/// the subsystem data should be parsed in a special way.</param>
/// <param name="subsystemData">
/// Link to the current file's subsystem data structure; initially it has dummy value
/// which will be replaced after we parse the whole subsystem data.</param>
/// <returns>List of "raw" variables; the actual variables are constructed from them later.</returns>
internal static List<RawVariable> ReadRawVariables(BinaryReader reader, long subsystemDataOffset, SubsystemData subsystemData)
{
var variables = new List<RawVariable>();
var dataElementReader = new DataElementReader(subsystemData);
while (true)
{
try
{
var position = reader.BaseStream.Position;
var dataElement = dataElementReader.Read(reader);
if (position == subsystemDataOffset)
{
var subsystemDataElement = dataElement as IArrayOf<byte>
?? throw new HandlerException("Cannot parse subsystem data element.");
var newSubsystemData = ReadSubsystemData(subsystemDataElement.Data, subsystemData);
subsystemData.Set(newSubsystemData);
}
else
{
variables.Add(new RawVariable(position, dataElement));
}
}
catch (EndOfStreamException)
{
break;
}
}
return variables;
}
private static IArray TransformOpaqueData(IArray array, SubsystemData subsystemData)
{
if (array is MatNumericalArrayOf <uint> uintArray)
{
if (uintArray.Data[0] == 3707764736u)
{
var(dimensions, indexToObjectId, classIndex) = DataElementReader.ParseOpaqueData(uintArray.Data);
return(new OpaqueLink(
uintArray.Name,
string.Empty,
string.Empty,
dimensions,
array as DataElement,
indexToObjectId,
classIndex,
subsystemData));
}
}
return(array);
}