I conducted the following tests regarding VTK's support for UTF8 encoded Chinese paths

Support
1

vtkDataSetReader ✓
vtkOBJReader ✓
vtkSTLReader ✓
vtkOpenFOAMReader : can update but get 0 block
vtkTecplotReader : can update but get 0 block
vtkCGNSReader : There is no problem with the individual CGNS files, but for the two associated CGNS files, there is an error “File Open Error: OLD - File does not exist” when reading the associated files, located in vtkCGNSReaderInternal.cxx

I perform encoding conversion from “CPACP” to “CPUTF8” using the following code：

std::string toUTF8(const char *ch)
{

    QString filepath = *new QString(ch);
    QByteArray cdata = filepath.toUtf8();
    std::string FilePath = cdata.toStdString();
    return FilePath;
}

I believe these issues can also occur on other non UTF8 systems. Is there any way to solve them？

2

If you use UTF8 everywhere then everything should work well. On Windows, make sure you set the application manifest to use UTF8.

3

Thanks for your reply. I’ll try it again.

4

Thanks, this is useful information. We would like these readers to just work with unicode filenames, without any configuration settings. There is an open issue for this (#17779).

  1. vtkOpenFOAMReader fails because it uses vtkDirectory, and vtkDirectory is broken for UTF-8 on Windows.
  2. vtkTecplotReader fails because it calls gzopen() for compressed files, it needs to use gzopen_w() on WIndows.
  3. vtkCGNSReader fails because the cgns library uses _open() instead of _wopen() on WIndows. This might not be fixable in VTK, it might have to be fixed in the cgns repository.
5

Thanks for your useful information! It sounds like most of these issues will be fixed internally in VTK, except for CGNS. Will those fixes be in version 9.4？

6

Most of the fixes will be in VTK 9.4. This includes vtkTecplotReader, vtkOpenFOAMReader, vtkTIFFReader, vtkNIFTIReader, vtkDICOMImageReader.

CGNS is unlikely to be fixed by then. There is a possibility VTK’s HDF readers will be fixed, since hdf5 1.15 will be utf8-friendly, but it doesn’t have an announced release date.

1 Like
7

The repair of these classes has been very helpful to me. Thank you again for your reply!