Fullscreen images and moving in a playlist displays the images offset for a few frames.

First and foremost consider this:

• Only RetroArch bugs should be filed here. Not core bugs or game bugs
• This is not a forum or a help section, this is strictly developer oriented

Description

This is probably dependent on hardware and settings, but when you select 'enter' on a playlist to zoom in to the thumbnails, then move around the underlying playlist or cycling the images to switch images, you might notice that the thumnail images have a small window where they show a 'centered' image, then there comes the second image to display and the other image is squished into the side. I can easily see this happening on fractions of second with a title screen on the left and the boxart on the right (btw this is another bug, imo, the 'first' thumbnail in the appearances setting is set to boxart and it appears on the right... depends on culture i guess).

Anyway on that situation it's like the title screen appears centered for a few or even one frame, then the box art comes in and moves it aside. It's a bit easy to see because there is a dividing transparent space between the images in the final result so you can see the 'title' in the center then the menu and it flashes. This is not because of the 'other game' in the previous index of the playlist, it also happens by cycling the images displayed. It's more apparent in certain games, i had good success seeing it on Doom 32x.

Expected behavior

The final image was constructed offscreen with both images displayed so flashing/resizing/moving images wouldn't be visible. I'm not sure what should happen if the 'partner' on this final image doesn't exist and you move

Actual behavior

Unsightly flashing of the title screen image to the menu.

Steps to reproduce the bug

1. [First step]
2. [Second step]
3. [and so on...]

Bisect Results

[Try to bisect and tell us when this started happening]

Version/Commit

• RetroArch: Version: 1.15.0 (Git e910eb9add) Jun 20 2023

Environment information

• OS: Linux 64bits
• Compiler: Compiler: GCC (11.3.0) 64-bit

No source file, test, or entry point is named. First reproduce the playlist thumbnail transition on Linux using RetroArch 1.15.0 and the Doom 32X example, then trace the fullscreen image rendering path; done means switching images no longer shows a centered or shifted image for any frame.