BackgroundPlotter not workin on Mac with vtk9

[banesullivan]

I still cannot get the BackgrounPlotter to work with VTK9.0 on Mac. See pyvista/pyvista#562 (comment)

cc @Leguark, since you all are using the BackgroundPlotter in GemPy, you may want to limit vtk in your setup.py until we get this fixed: vtk<9.0.0

cc @GuillaumeFavelier, are you all seeing this with MNE-Python?

[GuillaumeFavelier]

I know that we have a job on Travis configured with vtk 9.0.0 for MacOS but I'm not 100% sure it runs all the tests, it might skip a lot. We still have to get reports from users on MacOS that did the upgrade to vtk 9.0.0

[GuillaumeFavelier]

To move forward with this one, @banesullivan could you maybe try a very simple example like the default QVTKRenderWidgetConeExample and confirm that everything works fine for you?

I think the priority here is to understand where is the issue.

[larsoner]

Possibly related to initialize/start/show ordering?

https://discourse.vtk.org/t/vtk-9-pyqt-macos-no-rendering/3358/22

[larsoner]

(This thread also explains why macOS rendering worked for me at one point when building the wheels myself, but stopped working once I switched to using the official VTK wheels)

[cbrnr]

FWIW, toggling the "Eye Dome Lighting" setting made a figure change from completely black to actually show the figure correctly.

[banesullivan]

Thanks for the tip, @cbrnr - I will have to look into why that is...

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FYI: VTK 9.0.1 fixed this issue for me (see #16 (comment)) but @larsoner is still having trouble?

[larsoner]

I'm still having trouble with MNE examples, but it might be something we're doing at our end

[larsoner]

Okay I figured out the problem, enable_anti_aliasing gives me a black canvas:

import pyvista as pv
from pyvistaqt import BackgroundPlotter

p = BackgroundPlotter()
p.enable_anti_aliasing()
p.add_mesh(pv.Cone())

[larsoner]

... and also the VTK widget controls we have are only controllable by mouse clicks at 1/2 the correct location, meaning the VTK has some HiDPI problem with its widget controls and clicks...

[cbrnr]

And if you then toggle eyedome lighting, it works!

[larsoner]

The widgets work? Or antialiasing works? Or you need AA off / commented out plus eyedome toggle to see the simple example above?

[cbrnr]

Your example initially looks like this:

After clicking on View - Toggle Eye Dome Lighting, it looks like this:

[larsoner]

I think this was fixed by VTK in https://gitlab.kitware.com/vtk/vtk/-/merge_requests/7420 / 9.1, so we might as well close I think