Vertical Image Diagonal Line Issue

mfruckus · May 7, 2019, 3:12 PM

Hi everyone,

I’m new here and I’d like to start by thanking everyone for all of their inspired work.

I’m having an issue that I don’t believe is tied to the Magic Mirror but rather the raspberry pi in general.

I rotated the display near the beginning of my build and ever since then, when an image is moving on screen it passes through what I’d describe as fixed diagonal lines running through the screen. It looks as though the rectangular image is made up from 2 or 3 parallelograms and it’s only visible when an image moves on screen.

Anyone seen this before and/or have any idea for a fix?

Thanks in advance

sdetweil · May 7, 2019, 3:14 PM

are you using the fake gpu driver? some problems with rendering have been reported, particularly in the rotated layout

mfruckus · May 7, 2019, 3:16 PM

@sdetweil I’m really new to all of this so I’m not 100% certain if I am or not. Is there a way that I could check?

sdetweil · May 7, 2019, 3:25 PM

@mfruckus i have never done this so, searching yields this

http://www.raspberryconnect.com/gamessoftware/item/314-trying_out_opengl_on_raspberry_pi_3

mfruckus · May 7, 2019, 3:29 PM

@sdetweil Thanks for the info. I’m going to give it a shot and I’ll come back with results.

cheers

mfruckus · May 7, 2019, 4:46 PM

I tried out all of the options (Full Kernel, Fake Kernel, and Legacy).

For some reason, using the Full Kernel and the Fake Kernel somehow disregards my /boot/config.txt which tells it to rotate vertically. Changing the value and rebooting does nothing. I’m only able to be vertical at all when using Legacy.

I’m fairly confounded as to why I’m not even able to get the display vertical with Full KMS and Fake KMS. My hunch is that it may not be of huge importance to my diagonal line issue.

Even when using Legacy, if the display is horizontal, there’s no diagonal lines. It seems that it just wants to divide the vertical screen with a couple diagonal lines. There must be a solution though.

mfruckus · May 8, 2019, 7:18 PM

I’ve also tried installing just a clean raspbian stretch. However, the problem persists when I rotate the display with only the desktop environment of stretch running.

I’m now thinking that the 32" Samsung I’m using may be the issue and I’m going to try out another make/model.

mfruckus · May 10, 2019, 11:11 AM

At this point, from what I’ve read, the issue of the screen tearing when vertical seems to be related to using the legacy driver. Supposedly a switch to Full KMS should work but I need to rotate my screen using xrandr. Can anyone give me the breakdown on using xrandr to rotate my screen vertically?

Would be supremely appreciated

sdetweil · May 10, 2019, 1:08 PM

@mfruckus see

https://askubuntu.com/questions/95812/how-can-i-rotate-my-display-in-the-most-easy-way/95825

mfruckus · May 10, 2019, 1:08 PM

@sdetweil said in Vertical Image Diagonal Line Issue:

@mfruckus see

https://askubuntu.com/questions/95812/how-can-i-rotate-my-display-in-the-most-easy-way/95825

Thanks so much man. I got it working. This was the exact info I needed.

Rendering is still imperfect but there’s no screen tearing at all. Really really appreciate it. Going to post a detailed solution here shortly because this info is too hidden.