qtVCP not working for RPI 2.8 image

I was excited to see that there is now a Linuxcnc image for the RPI4. I downloaded and installed and when to try out the QTVCP interface samples. None of them work. Attached is the error report from trying to run the qtDragon configuration.

Any help in better understanding what is going on would be helpful. I assume that some of the libraries this depends on are now found or compatible on the RPI, however it isn't making sense to me.

Can anyone point me in the right direction?

One problem is that user pi can't write to that directory without root privilege. It should be writing to the config directory.
Regardless, it won't work anyway if you want a graphics display. The Rpi uses OpenGL ES and qtvcp uses OpenGL. They are incompatible. I did manage to create a version that uses VTK but it's untested and not yet posted to github. I think one of the other GUIs, like Axis, might run OK, never checked. I would like to run my machine with a pi as well but not having much luck getting the graphics to work.

I should clarify. Linuxcnc works fine on the pi, it's QtDragon with the qt5_graphics library that doesn't.

I did change the permissions on that folder, but ran into a bunch more problems.

So I suppose for now that qtvcp and RPI won't play nice together?

Changing permissions to any directory under /usr is a bad idea.
Yes it is a security issue.
But, another big issue is accidentally deleting things that should not be deleted.

I just uploaded the files to make QtDragon work with VTK. It's functional, but not as versatile as qt5_graphics. There's also the .deb package you need to install VTK. My ultimate goal was to make it look like qt5_graphics but there are some GL functions not available in VTK. I also explored porting to OpenGL ES but that's another whole can of worms. github.com/persei802/vtk Place them in your config directory, replacing the current ones.
Here's a screenshot of QtDragon on a RPi4
Problems? Let me know.
Jim

Hi Jim,
I installed the rpi4 image and configured for my machine.
So far so good with Axis, but I wanted to use QtDragon so I did the following actions:
> sudo apt install python-vtk6 (no errors)
> downloaded the files in your github and copied in /home/pi/linuxcnc/configs/vtk
> installed the .deb package (double cliked on it and gave permissions)
Now if I run linuxCNC under "My Configurations" I have the 3 qtDragon variants, but none of them are working.
I see the splash screen of LinuxCNC and then it simply doesn't start. No messages.
Any Idea? What can I try to debug it?
Thank you

If you start linuxcnc from a terminal, it should print out some startup info and any error messages. That way you may get a clue what the problem is.

Sorry, I had to do it in the first post...
I attached the log,
but I think this is the point:

[QTvcp.QTVCP.QT_MAKEGUI][CRITICAL] module 'qtdragon_handler' skipped - import error: (qt_makegui.py:280)
Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/qtvcp/qt_makegui.py", line 278, in _load_handlers
mod = __import__(basename)
File "/home/pi/linuxcnc/configs/qtdragon/qtdragon_handler.py", line 17, in <module>
from vtk_backplot import VTKBackPlot
File "/home/pi/linuxcnc/configs/qtdragon/vtk_backplot.py", line 13, in <module>
import vtk.qt
ImportError: No module named qt
Shutting down and cleaning up LinuxCNC...
task: 1552 cycles, min=0.000164, max=0.011806, avg=0.009890, 0 latency excursions (> 10x expected cycle time of 0.010000s)
Note: Using POSIX realtime

Sorry I'm not a linux guy..

ImportError: No module named qt

Is QT installed?
If you type:You should see libvtk7.1-qt along with a bunch of other stuff.
Also, not sure about double clicking on a deb package. To install it, you need to :

ok, this is what I get:I see 7.1.1-qt5py2-1 so looks like it's installed as far as I can tell.
I also tried to reinstall the package but no luck.
Just for curiosity I noticed there are more python version installed (2.6, 2.7, 3 and 3.7) maybe that's normal but I don't know where to look at...
thank you