ENH: Qt 6 - Githubissues

GuillaumeFavelier commented 3 years ago

PySide6 and PyQt6 have been released and now work is ongoing on pytest-qt (actually 4.0.0 is just around the corner) and qtpy to catch up.

Now it seems the main blocker for pyvistaqt comes from vtk because the QVTKRenderWindowInteractor does not support these new implementations. From vtk/master:

if PyQtImpl is None:
    # Autodetect the PyQt implementation to use
    try:
        import PyQt5
        PyQtImpl = "PyQt5"
    except ImportError:
        try:
            import PySide2
            PyQtImpl = "PySide2"
        except ImportError:
            try:
                import PyQt4
                PyQtImpl = "PyQt4"
            except ImportError:
                try:
                    import PySide
                    PyQtImpl = "PySide"
                except ImportError:
                    raise ImportError("Cannot load either PyQt or PySide")

An alternative would be to define our own version as it is done for example in mayavi

larsoner commented 3 years ago

An alternative would be to define our own version as it is done for example in mayavi

This might not be a bad idea, especially since Mayavi's version differs from VTK's (I think it's newer), and VTK's version is referred to as "contributed code" and not really supported:

It would be great if we could at least fix these macOS bugs, and then preferably contribute them back to VTK (if they'll accept them).

To me Qt6 would be a secondary priority, because it looks like Qt6 support was added only 6 months ago, so probably isn't in VTK6:

https://discourse.vtk.org/t/how-to-get-vtk9-qt6-working-together/4927

I assume we need to wait for VTK9.1 or 10 to be released (no idea what the timelines are), I would look into that and also into the Qt6 thread above (and any other ones you might find) to see what their state of support is actually like.

GuillaumeFavelier commented 3 years ago

VTK's version is referred to as "contributed code" and not really supported

Indeed, from (VTK's developper) David Gobbi:

This issue is with regards to vtkmodules/qt/QVTKRenderWindowInteractor.py, which is a community-contributed class (this class does not make use of the GUISupportQt C++ module). As far as I know, none of the core VTK teams use this class. [...] I honestly doubt that any of the VTK developers have time to maintain this class.

I was not aware of this, many thanks for the additional informations.

Mayavi's version differs from VTK's (I think it's newer)

It's definitely worth taking a look if we seriously consider maintaining our own :+1:

I assume we need to wait for VTK9.1 or 10 to be released

I'm interested in working on a PR for this but not until the situation is settled for qtpy.

GuillaumeFavelier commented 3 years ago

Another package to consider is ipython. In my experiments, I ran into:

    from IPython.external.qt_for_kernel import QtGui
../anaconda3/envs/mne-py39/lib/python3.9/site-packages/IPython/external/qt_for_kernel.py:94: in <module>
    api_opts = get_options()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

    def get_options():
        """Return a list of acceptable QT APIs, in decreasing order of
        preference
        """
        #already imported Qt somewhere. Use that
        loaded = loaded_api()
        if loaded is not None:
            return [loaded]

        mpl = sys.modules.get('matplotlib', None)

        if mpl is not None and not check_version(mpl.__version__, '1.0.2'):
            #1.0.1 only supports PyQt4 v1
            return [QT_API_PYQT_DEFAULT]

        qt_api = os.environ.get('QT_API', None)
        if qt_api is None:
            #no ETS variable. Ask mpl, then use default fallback path
            return matplotlib_options(mpl) or [QT_API_PYQT_DEFAULT, QT_API_PYSIDE,
                                               QT_API_PYQT5, QT_API_PYSIDE2]
        elif qt_api not in _qt_apis:
>           raise RuntimeError("Invalid Qt API %r, valid values are: %r" %
                               (qt_api, ', '.join(_qt_apis)))
E           RuntimeError: Invalid Qt API 'pyside6', valid values are: 'pyside, pyside2, pyqt, pyqt5, pyqtv1, pyqtdefault'

GuillaumeFavelier commented 3 years ago

Quick update: the issue with ipython is solved in 7.27

pyvista / pyvistaqt

ENH: Qt 6 #114