Raspberry Pi - error in pyglet

Coding
1

Hi all,
I’ve been playing around with installing psychopy on the raspberry-pi 4b (running raspbian buster). My goal is to try out the timing test and show some simple stimuli. I am facing errors which leads to a Segmentation fault. I am trying to understand what that is about

My installation:

Issue:
Importing psychopy works fine

from psychopy.visual.window import Window as w  #ok

However, I get a Segmentation fault when I actually open a window:

w() # open a psychopy window results in **Segmentation fault** no error msg

I have been debugging this issue and I have narrowed it down to an error in
Window._setupShaders() called by Window._setupGL() called by Window.__init__().

More specifically, it seems to be failing gltools.linkProgramObjectARB(prog) for a prog value of 55. gltools seems to call pyglet.GL.glLinkProgramARB. I have followed the error to pyglet.

I am curious if anyone else has faced this issue. What could be the cause of the error?

Thanks for your time

2

@balajisriram I’m experiencing the exact same issue, but with PsychoPy (v2020.1.2). Using GUI dialogs works fine, but rendering a Window fails with a ‘Segmentation fault’ message and no error code.

I did fix it though. Try rolling back PsychoPy to v3.2.4 using the command:

python3 -m pip install psychopy==3.2.4

I was able to render Windows once I did that. I also uninstalled pygame, though I don’t think that influenced this.

Let me know if that fixes your issue!

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Thank for the post. I’m actually looking into getting PsychoPy better supported on the Raspberry Pi 4. There is a bit of blind spot in development since work on the graphics system is usually tested on Nvidia, AMD, and Intel hardware. Since the RPi4 is looking like a suitable desktop replacement with good GPU support, I’m going to ensure PsychoPy is compatible with it in the future.

1 Like
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Thanks - I’ll keep my eyes peeled for any updates on this front. Glad to help write/test out code as and when that may be necessary

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I haven’t tried earlier versions - thanks. I’ll give it a try soon

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The fact it worked before in previous versions was a “happy accident” since the RPi OpenGL driver was limited to OpenGL 2.0. I’ve been moving things over to newer OpenGL specs since stuff has been breaking on Intel cards which a large majority of users have. I’ll try to keep compatibility going with OpenGL versions the RPi supports in the future, possibly by detecting the platform and selecting a code path.

Having PsychoPy on the RPi is something I personally want supported since an experiment can directly access the GPIO giving near real time triggering and event callbacks without the need for a separate device.

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Hey mdc. Any update? Our lab are considering an independent visual stimulation system for mice controlled using GPIO commands to a rasp pi 4 and a screen. I was wondering if we connect an external lcd on the pi, would we be in theory, able to control the screen using psychopy?

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Thanks for your interest anas-masood. mdc, is this a feature that is undergoing any development? do you have a sense of how to support psychopy on r-pi? If you already have a strategy in mind, I don’t mind working through the coding to enable support.

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Thank you, this also worked for me