@alan-miller3 said in need help understanding screen size/orientation etc.:

@dankcushions

ok, physically my display's visible area is 15 x 12 inches. That's a 5:4 ratio.
So I changed my screen resolution to 1280x1024@60Hz (also a 5:4 ratio) and rebooted.

if that’s the native resolution of the screen then fine

vide_rotation=3 is still set in /opt/retropie/configs/all/retroarch.cfg

After starting a game and hitting tab, the video options offer 3:4 or 7:9 or cocktail.

tab should get you to the MAME menu (not retroarch(. you probably don’t want to to be changing options there.

Disabling any of the options (backdrops, overlays, bezels, marquees, etc.) doesn't seem to do anything.

because bezel project adds retroarch bezels, not MAME ones. how did you install it? presumably the same script permits the disabling/removal of the bezels.

or did you use a pre-configured image?

new2.jpg

If I revert the video_rotation (back to 0) in /opt/retropie/configs/all/retroarch.cfg
I still get the same 11 x 11 screen with "Arcade" bezels but without rotation so players 1 and 2 are both looking at the screen from the side.

Is it the fact that the original game was intended to be on a square screen?

no, it a a 4:3 crt screen rotated on its side (so effectively 3:4)

b1b9c82c-b29a-4800-9a43-098f4b48d49e-image.jpeg
https://i.ebayimg.com/images/g/hg4AAOSwMBZiVBKN/s-l500.jpg

@retrofam I wonder if Auto-Rotate is overriding that. You might need to disable it.

@iandaemon thats exactly what i did and didnt catch thank you

The Pi4 doesn't support the rotate_display parameter anymore - see https://www.raspberrypi.org/documentation/configuration/config-txt/video.md. At some point, it was possible to use display_rotate=2 to flip the screen, but after a firmware update this year, this is also no longer supported.

There is some guidance on how to rotate the display on the Pi4 here or at a similar post here in the forums.