Partial display offset ingame (very old bug, but appears to be not reported)
(I tried approx every options but it is always present even with OpenGL)

Looking at this, its probably a game using GL_CLAMP to sample. A fix for these old game techniques requires a feature to be added so I'll first verify if that is the case and skip it for now if it is. A texturing rewrite is scheduled for soon and will automatically fix such problems.
Looks to be a legit issue surprisingly, not clamping as I initially thought. Looking back, I seem to have gone down this same path 3 years ago but didn't reach a conclusion.
Ok, turns out we completely forgot about 24-bit render targets; they're very poorly supported on rpcs3. I'll write up some hardware tests, this is now a major task as initial half-fix is not working correctly.
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Ok, turns out we completely forgot about 24-bit render targets; they're very poorly supported on rpcs3. I'll write up some hardware tests, this is now a major task as initial half-fix is not working correctly.