Slight black border on left and right hand sides of the screen

Our mod has always had these 1-2 pixel borders on the left and right hand sides of the screen. Normally it's hard to see because it's black, but in certain cases, like a black image which is meant to cover a CG, it can result in the CG showing where the borders would be. Users usually report this happening on Onikakushi as it's the first time they see the graphical glitch.

The unmodded game does not have this issue.

@tellowkrinkle suggested it was a rounding issue, I'll look into that first when I (eventually) have a look at the issue:

> Probably a rounding issue somewhere
> I bet we (int) things, and with floating point error it might go over or under the target, causing - 1 pixel vs not - 1 pixel
> Try setting the aspect ratio to 0.65251 or something and see if that fixes it

modded:

unmodded:

Look for aspect ratio or screen coordinate calculations in the codebase, likely in rendering or viewport setup. The issue mentions a rounding error when converting floats to ints; search for casts or integer truncations in graphics code. Test with the suggested aspect ratio 0.65251 to see if the black borders disappear, and verify by comparing modded vs unmodded rendering.

Rédigé par le modèle d'indexation à partir du texte de l'issue.